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Compaction of forest soils with heavy logging machinery affects soil bacterial community structure

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Abstract

Soil compaction is widespread but tends to be most prevalent where heavy machinery is used in landfill sites, agriculture and forestry. Three forest sites strongly disturbed by heavy logging machinery were chosen to test the physical effects of different levels of compaction on soil bacterial community structure and soil functions. Community analysis comprised microbial biomass C and T-RFLP genetic profiling. Machine passes, irrespective of the compaction level, considerably modified soil structural characteristics at two soil depths (5–10 cm; 15–20 cm). Total porosity decreased up to 17% in the severe compaction. Reflected in this overall decline were large decreases in macroporosity (>50 μm). Reduction in macroporosity was associated with higher water retention and restricted gas exchange in compacted soils. The strongest effect was observed in the severely compacted wheel tracks where air and water conductivities were reduced permanently to 10% or even lower of the original conductivities of undisturbed soils. Very slow drainage in combination with a dramatically reduced gas permeability led to unfavorable soil conditions in severely disturbed traffic lanes reflecting the changes in the total bacterial community structures at both soil depths. Additionally, microbial biomass C tended to be lower in compacted soil. Our results indicate that the type of severe treatments imposed at these forest sites may have strong adverse effects on long-term soil sustainability.

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... This can reduce soil functions like water infiltration, hydraulic conductivity, air permeability and mobility of nutrients, thus, influencing the micro-environmental conditions for microbial activity (Beylich et al., 2010;Wolf et al., 2013). These results are consistent with some previous reports that showed influence of bulk-density on geometry of soil pores (Frey et al., 2009;Kim et al., 2010;Nawaz et al., 2012). Frey et al. (2009) reported a 17 % reduction in total porosity in severely compacted soil. ...
... These results are consistent with some previous reports that showed influence of bulk-density on geometry of soil pores (Frey et al., 2009;Kim et al., 2010;Nawaz et al., 2012). Frey et al. (2009) reported a 17 % reduction in total porosity in severely compacted soil. Kim et al. (2010) studied the effect of compaction on 3D macropore geometry in undisturbed soil cores. ...
... The results obtained in this study are consistent with several other studies which reported a reduction in the microbial community and its activity at higher bulk-density compared to the soil packed at lower bulk-density (Li et al., 2002;Frey et al., 2009;Pupin et al., 2009;Dick et al., 1988;Smeltzer et al., 1986;Chang, 2007, Tan et al., 2008). For example, Pupin et al. (2009) reported a reduction of 22-30 % in the number of bacteria at 1.7 g cm -3 bulk-density compared to the control (1.3 g cm -3 ). ...
... Soil compaction is a ubiquitous challenge across managed terrestrial ecosystems (Soane et al., 1981;Hamza and Anderson, 2005;Drewry et al., 2008;Batey, 2009;Chamen et al., 2015;Cambi et al., 2015). It is defined as a shift in the physical makeup of the soil entailing changes in the amount, size distribution, shape and connectivity of pores, which constrain the movement and storage of fluids: water and air (Soane et al., 1981;Frey et al., 2009;Schwen et al., 2011;Guenette and Hernandez-Ramirez, 2018a). In other words, soil compaction, loosening, or alleviation alters moisture-aeration relationships by impacting the volume and configuration of pores in several ways (Lipiec and Hatano, 2003;Shestak and Busse, 2005;Drewry et al., 2008;van der Weerden et al., 2012;Hernandez-Ramirez et al., 2014). ...
... As opposed to unorganized traffic patterns, confining equipment movements to systematically designated tracks has been recommended as a means to reduce applied compaction, prevent further detrimental compaction, and enable soil alleviation in forests (Cambi et al., 2015), pastures (Drewry et al., 2008), and croplands (Guenette et al., 2019). This approach is known in croplands as controlled traffic farming (CTF) (Hamza and Anderson, 2005;Antille et al., 2015;Chamen et al., 2015) and in forests as permanent skid trails (Teepe et al., 2004;Frey et al., 2009;Warlo et al., 2019). Conversely, in the case of pastures, soil compaction mainly originates from recurrent livestock trampling, particularly under wet soil conditions (Oenema et al., 1997;Piwowarczyk et al., 2011;Treweek et al., 2016;van der Weerden et al., 2017). ...
... Subsequently, it can be postulated that a dynamic balance between water and O 2 in the soil is a master control for the N availability and transformations that are involved in N 2 O production and consumption. It is suggested that quantifying gas permeability (Douglas and Crawford, 1993;Sitaula et al., 2000;Frey et al., 2009;Ball et al., 2012), soil oxygen concentrations Owens et al., 2016;Grant et al., 2020) or redox potential (Hernandez-Ramirez et al., 2009) may further enhance our current understanding of compaction effects on N 2 O emissions. ...
Article
Nitrous oxide (N2O) is a potent greenhouse gas and precursor of ozone layer depletion. Managed terrestrial ecosystems are major anthropogenic sources of N2O, primarily generated in the soil. The physical makeup of the soil interplays with the underlying biochemistry that produces N2O. Therefore, it has been conceptualized that either compacting or loosening the soil will alter N2O emissions; however, a unified framework of these relationships is yet to be established. Here, we compiled, reviewed and analyzed available field studies that have evaluated how applied compaction or alleviation of compacted soils impacts N2O emissions. Of the 108 available pairwise comparisons, 82 % of the cases showed detrimental increases in N2O emissions caused by increased compaction. Overall, N2O emissions nearly doubled because of soil compaction effects (P < 0.05). This doubling of N2O emissions was linked to a relative reduction of 9 % in soil porosity (i.e., 0.05 cm³ cm⁻³) caused by applied compaction. This linkage to soil porosity was clearly evident in both croplands and pastures. Across the managed terrestrial ecosystems evaluated, the strongest relative effects of compaction on N2O emissions were found in forest and pasture soils. Overall, N2O emissions in forest soils showed a fivefold increase caused by compaction (P < 0.05; n = 11). This massive response in forest soils can be attributed to: i) their low N2O emission baseline; ii) their acidic pH, which intrinsically favors N2O emissions; iii) having some of the heaviest traffic loads found across our meta-analysis (e.g., 16 Mg); and iv) an increase in soil microporosity. Pasture soils also displayed substantial compaction effects on N2O emissions, with a threefold increase (P < 0.05; n = 25). This was explained in part by the elevated nitrogen input rates in pastures (e.g., 600–1000 kg N ha⁻¹). Conversely, alleviation of soil compaction by implementing controlled traffic farming (CTF) in vegetable and grain croplands reduced N2O emissions consistently in all available pairwise comparisons (P < 0.05; n = 19). At the field scale, CTF greatly decreased N2O emissions by one-third compared with farmlands managed with conventional random traffic (4.48 versus 2.86 kg N2O-N ha⁻¹). However, after reviewing the available literature, we witnessed a paucity of information about how long it takes for soils to self-alleviate from the detrimental effects of compaction on N2O emissions. Additionally, insights gained through meta-analysis revealed the interplay of soil compaction with underlying heavy textures, acidic pH, and reduced porosities, which collectively exacerbate N2O emissions. Nevertheless, these complex interactions operate differentially across contrasting land use options.
... The decline in C and nutrient stores, and the quality and quantity of SOM following biomass harvest events can have adverse effects on the structure, size, and function of microbial communities (Colombo et al., 2016;Foote et al., 2015;Frey et al., 2009). Microbial communities are considered regulators of nutrient cycles because of the intervention in the decomposition process and because they control the availability of nutrients to vegetation through immobilization or mineralization (Falkowski, Fenchel, & Delong, 2008). ...
... La disminución en las reservas de C y nutrientes, y la calidad y cantidad de MOS posterior a los eventos de cosecha de biomasa pueden tener efectos adversos en Removal or alteration of SOM inputs, due to forest harvesting, decreases the proportion of microbial biomass and enzymatic activity, as indicated by positive relationships between microbial biomass, enzymatic activity and total C and N content present in the soil (Adamczyk, Adamczyk, Kukkola, Tamminen, & Smolander, 2015;Mummey et al., 2010). Another important factor is soil compaction, which decreases microbial biomass through reduced aeration and water conductivity preventing development and proliferation (Colombo et al., 2016;Frey et al., 2009). Forest disturbances also differentially affect the composition and resilience of soil microbial communities due to their physiological ability to maintain functionality under conditions of decreased nutrients (Ball, MacKenzie, DeLuca, & Montana, 2010;Hynes & Germida, 2012;Rasche et al., 2011). ...
... The influence of the plant community on the availability of nutrients is controlled by three factors: 1) physical environment, mainly temperature and humidity la estructura, tamaño y función de las comunidades microbianas (Colombo et al., 2016;Foote et al., 2015;Frey et al., 2009). Las comunidades microbianas son consideradas reguladoras de los ciclos de nutrientes por su intervención en el proceso de descomposición y porque controlan la disponibilidad de estos para la vegetación, mediante la inmovilización o mineralización (Falkowski, Fenchel, & Delong, 2008). ...
Article
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Introduction: The increase in the intensity of wood harvesting has a negative influence on ecosystem functions of soils in temperate and boreal forests. Objective: To understand the impacts of intensive and extensive forest management methods on the physical, chemical and biological properties of soils, and consequences on nutrient availability and stabilization processes in temperate and boreal forests. Results and discussion: Intensive forest management methods can generate greater imbalance in the processes of availability and stabilization of nutrients, compared to selective methods. The impact is reflected in the deterioration of soil structure and the decrease of nutrient reserves and microbial communities. These damages affect fertility and functionality of soil, decreasing long-term productivity. Affectations depend on the intensity of biomass extracted, environmental conditions and site preparation. This makes evident the need to monitor forest management and its impact on soil ecology in temperate forests, which maintains long-term productivity and ensures the availability of wood volumes. Conclusion: In Mexico, the impact of forest management has been scarcely analyzed and it is indispensable to understand the functional changes in the processes that determine soil fertility and forest productivity.
... La compression de la bioporosité amène à chasser l'eau vers les cavités aériennes (micropores) et aboutit à la séquestration de l'humidité et à la réduction de l'aération vers l'anoxie (figure 2) (Bottinelli et al., 2014b;Frey et al., 2009;Gaertig et al., 2002;Horn et al., 2004). Le tassement se traduit directement par l'augmentation de la densité apparente du sol, qui forme l'indice majeur de la compaction (Ampoorter et al., 2010). ...
... Elle dépend essentiellement de la teneur en argile et de l'humidité fournies par l'état de la porosité (Bronick & Lal, 2005;Hillel, 2004aHillel, , 2004b. la compaction conduit à une altération de l'arrangement spatial des constituants du sol et donc à une altération de la structure par compression des biopores et destruction de la connectivité (Bottinelli et al., 2014b;Frey et al., 2009;Hamza & Anderson, 2005;Herbauts et al., 1996). L'application d'une contrainte par le passage des engins conduit à la réduction significative de la porosité totale du sol, cette réduction devient plus grave en passage intensif des engins (Solgi et al., 2016). ...
... Un rôle très important est joué par les microorganismes dans l'approvisionnement des nutriments dans le sol. mais la biomasse microbienne sera altérée par le microclimat anoxique et l'augmentation de l'humidité résultants du tassement (Frey et al., 2009). Aussi, le tassement affecte indirectement la performance microbienne par l'altération des microarthropodes (Lussenhop, 1992). ...
Thesis
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La compaction et l'orniérage des sols forestiers par les engins lourds constituent des enjeux très importants concernant la gestion durable des forêts. Dans cette thèse nous avons examiné l'état d'orniérage d'un massif forestier du nord de la France (forêt de Compiègne) à l'aide d'un levé LIDAR (Light Dectection And Ranging) aéroporté, puis nous avons évalué la résilience des sols après tassement à une échelle pluri-décennale. Les modèles numériques de terrain (MNT) traités par "local relief modelling" (LRM) ont été utilisés pour proposer un indicateur de la densité de l'orniérage (RD). La résilience physique et biologique des sols après le tassement a été évaluée pour deux chronoséquences (Podzol et Luvisol) établies par une approche de substitution temps / espace couvrant une période de 45 ans. Les paramètres mesurés pour étudier la résilience sont : la résistance à la pénétration, la respiration du sol, le pH, les traits hydromorphes, l'enracinement, ainsi que la diversité de microarthropodes évaluée par l'indice QBS-ar. Nous trouvons qu'à l'échelle de tout le massif, la surface impactée par les passages d'engins est en moyenne de 40% mais aussi qu'elle varie à une échelle très fine au sein des unités de gestion. L'occurrence de nombreuses espèces herbacées varie avec la densité d'orniérage. La respiration à la surface du sol et la diversité de microarthropodes sur l'horizon 0-10 cm sont restituées en moins de 10 ans. La résistance à la pénétration du sol se reconstitue progressivement depuis la surface vers la profondeur. La résilience complète sur une profondeur de 30cm est évaluée à 60 ans pour le Luvisol et 80 ans pour le Podzol
... Since the introduction of larger machines in forestry, their effect on the environment has been a continuously debated topic. Soil protection is a particular point of concern [1]. With increased awareness and defined restrictions, the surrounding conditions for forest work have become more important, as global warming forces forestry contractors to work under suboptimal conditions outside the frost period [2]. ...
... To observe a rut deepening effect, soil stress was then provoked by multiple passes over the area of interest with a loaded machine in a straight line while the changes were recorded (Table 2). For the layout documentation, the measuring points were named according to the tested machine configuration (1)(2)(3)(4), the recording type when multiple methods were used (a: TLS; b: manual), the recording cycle (A, B), and the consecutive number of measuring points per setup (e.g., 1a_A1). ...
... To create a multi-temporal DTM that is further used to enhance the data collected by manual measurements, a FARO Focus 3D X330 terrestrial laser scanner (TLS) was positioned outside the lane of the skid trail at four measurement points during the "Tharandt" campaign. With this setup, a scan of each measuring point was made after every second pass of the machine in the frequency [0, 1,3,5,7,9,11] for the measurements 1a and [0, 2,4,6,8,10] for the measurements 2a (see also Table 3). [33,42,44,47]). ...
Article
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In 2019, the machine manufacturer HSM presented a forwarder prototype for timber hauling in cut-to-length processes fitted with a new 10-wheel triple-bogie (TB) setup approach aimed at promoting sustainable forest management by reducing the ecological impact of forest operations, especially under soft-soil working conditions. The purpose of our study was to assess the resulting soil-protection effect emerging from additional wheel-contact surface area. For this, the rut development under known cumulative weight, related to the soil conditions of shear strength and moisture content, was recorded for later comparison. Additional terrestrial laser scanning (TLS) was used to generate a multi-temporal digital terrain model (DTM) in order to enhance the data sample, assess data quality, and facilitate visualization of the impact of local disturbance factors. In all TB configurations, a rut depth of 10 cm (5.8–7.2 cm) was not exceeded after the hauling of a reference amount of 90 m3 of timber (average soil shear strength reference of 67 kPa, volumetric water content (VMC) 43%). Compared to a reference dataset, all observed configurations ranked in the lowest-impact machine categories on related soil stability classes, and the configuration without bogie tracks revealed the highest machine weight to weight distribution trade-off potential.
... La dégradation majeure induite par le tassement lors de la circulation d'engins lourds est l'augmentation de la masse volumique apparente par compaction et modification de l'espace porale. Frey et al. (2009) a mesuré une augmentation moyenne de la masse volumique apparente ρ d sur 3 sols forestiers après le passage d'engins à 0-5 cm (15-20 cm) de 17% (21%) pour une dégradation modérée des sols et de 20% (23%) pour une dégradation sévère. Pour la dégradation sévère, l'augmentation de ρ d est associée à une diminution de la porosité totale de 17% (19%) dont 60% correspond au volume des macropores. ...
... Il a également mesuré une diminution rapide du K sat sur cloisonnement circulé en condition humide contre une diminution graduelle sur cloisonnement circulé en condition sèche. Frey et al. (2009) ont mesuré la conductivité hydraulique suite à la dégradation de sols forestiers sous différentes intensités définies par les profondeurs d'ornière ( Fig. 1.10a). Ils ont montré une diminution de 10% de K sat pour chaque classe d'ornière, présentée dans la Figure 1.10b, lorsque l'humidité des sols dépasse la capacité au champ. ...
... Forest soil compaction has increased with heavy logging machinery like harvesters, skidders and forwarders (Greacen et Sands, 1980). The consequences of soil compaction are now well known, as changes in soil structure with the increase of the dry bulk density (Kozlowski, 1999;McNabb et al., 2001;Ampoorter et al., 2007) and the reduction of total pore volume, especially macroporosity (McNabb et al., 2001;Frey et al., 2009). The loss of large pore considerably affects water retention, soil aeration (Ballard, 2000;Frey et al., 2009) and infiltration capacity (Kozlowski, 1999). ...
Thesis
L'augmentation de la mécanisation lors de l'exploitation forestière combinée aux changements climatiques augmente le risque de circuler dans les mauvaises conditions et donc de dégrader les sols. C'est pourquoi il est nécessaire de développer des outils d'aide à la décision capables de prédire la praticabilité des sols forestiers. Cependant, évaluer la praticabilité avec des outils simples et des données facilement accessibles est complexe. En effet, elle dépend de multiple facteurs : la susceptibilité du sol à se déformer, la charge appliquée, le seuil de déformation toléré et l'état hydrique du sol. Ce travail vise à mieux comprendre et prévoir la dynamique hydrique des sols forestiers et des cloisonnements (i.e. chemins dédiés à la circulation des engins forestiers). Les objectifs sont les suivants : (i) améliorer notre compréhension de l'effet du tassement sur la teneur en eau des sols forestiers, (ii) paramétrer un modèle de fonctionnement hydrique en contexte forestier et (iii) être capable de prédire l'humidité des sols dans un contexte opérationnel. Nous avons mis en place un observatoire des cloisonnements qui a permis de fournir une base de données sur les propriétés hydrodynamiques des sols forestiers et sur l'évolution de la teneur en eau. Nous avons estimé les paramètres hydrodynamiques (PH) avec la méthode BEST sur des binômes de sols circulés-non circulés. Nous avons développé une loi de passage prédisant les valeurs de la teneur en eau à saturation et de la conductivité hydraulique à saturation des sols circulés à partir de ceux non circulés. Ensuite, nous avons paramétré un modèle de fonctionnement hydrique mécaniste basé sur l'équation de Richards en contexte forestier. Nous avons évalué la capacité du modèle à prédire la teneur en eau selon différents jeux de PH estimés par : la méthode BEST, une fonction de pédotransfert FPT ou calage. Le modèle combiné aux PH estimé par la méthode BEST mène à des problèmes de dessèchement de la couche intermédiaire en période estivale. L'utilisation d'une FPT conduit à un plus faible pouvoir prédictif mais ne simule la phase de dessèchement. La stratégie choisie consiste à utiliser la méthode BEST comme première estimation des PH et ensuite d'en caler certains par inversion. Enfin, nous avons développé un modèle empirique utilisable en conditions opérationnelles. Nous avons utilisé le modèle mécaniste pour générer une base de données virtuelle permettant (i) d'identifier les principaux mécanismes impliqués dans la dynamique de dessèchement des sol à prendre en compte et (ii) de caler et valider le modèle empirique. Il est capable de prédire le "jour de praticabilité" avec une résolution de 1.5 à 2.5 jours en période estivale. En période hivernale, sa précision n’est pas satisfaisante (rmse = 8.4 j), elle s'explique par la sensibilité du modèle aux évènements pluvieux fréquents et rapprochés. Le modèle empirique s'applique pour une seule configuration "sol x peuplement x climat x seuil" et mérite d'être calé dans d'autres contextes.
... Created skid trails and ruts by logging operations (Figure 1) can considerably disturb soils physical, chemical, and biological properties and severely alter the forest ecosystem function (Heninger et al., 2002;Powers et al., 2004;Agherkakli et al., 2010;Cambi et al., 2015). For example, soil compaction influences between 10 and 70% of the logged stand, indicating its substantial potential to disturb the soil ecosystem and forest (Frey et al., 2009;Picchio et al., 2012). ...
... Commonly, a low soil bulk density makes the soil more prone to compaction (Williamson and Neilsen, 2000;Powers et al., 2004). An increased bulk density of forest soils due to compaction can reduce the total porosity by 50-60% (Frey et al., 2009;Picchio et al., 2012;Solgi and Najafi, 2014). Reduction in soil total porosity dramatically disturbs the soil oxygen diffusion and water balance, the latter causing waterlogging, runoff, and erosion (Jansson and Johansson, 1998;Startsev and McNabb, 2000;Grace et al., 2006;Ampoorter et al., 2007;Schack-Kirchner et al., 2007). ...
... Compaction may also affect microbial biomass carbon (MBC) in forest soils. In general, soil compaction remarkably reduces soil MBC, due to reduction in total porosity, pore connectivity, and air and water supply (Wronski and Murphy, 1994;Breland and Hansen, 1996;Startsev et al., 1998;Tan et al., 2008;Frey et al., 2009), reducing the availability of key growth resources (oxygen, dissolved organic carbon, mineral nutrients, etc.) to soil microorganisms. In contrast, some other studies observed no significant impact of compaction on MBC (Ponder and Tadros, 2002;Jordan et al., 2003;Nazari et al., 2020). ...
Article
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Soil compaction associated with mechanized wood harvesting can long-lastingly disturb forest soils, ecosystem function, and productivity. Sustainable forest management requires precise and deep knowledge of logging operation impacts on forest soils, which can be attained by meta-analysis studies covering representative forest datasets. We performed a meta-analysis on the impact of logging-associated compaction on forest soils microbial biomass carbon (MBC), bulk density, total porosity, and saturated hydraulic conductivity (K sat) affected by two management factors (machine weight and passage frequency), two soil factors (texture and depth), and the time passed since the compaction event. Compaction significantly decreased soil MBC by −29.5% only in subsoils (>30 cm). Overall, compaction increased soil bulk density by 8.9% and reduced total porosity and K sat by −10.1 and −40.2%, respectively. The most striking finding of this meta-analysis is that the greatest disturbance to soil bulk density, total porosity, and K sat occurs after very frequent (>20) machine passages. This contradicts the existing claims that most damage to forest soils happens after a few machine passages. Furthermore, the analyzed physical variables did not recover to the normal level within a period of 3-6 years. Thus, altering these physical properties can disturb forest ecosystem function and productivity, because they play important roles in water and air supply as well as in biogeochemical cycling in forest ecosystems. To minimize the impact, we recommend the selection of suitable logging machines and decreasing the frequency of machine passages as well as logging out of rainy seasons especially in clayey soils. It is also very important to minimize total skid trail coverage for sustainable forest management.
... Soil compaction is one of the undesired consequences of using heavy equipment on forest sites, reducing tree growth [1,3] and most likely also affecting soil microbial properties to a largely unknown extent. Compaction has been found to reduce microbial biomass C (MBC) contents in the forest soil [4,5], which has been associated with negative changes in physical soil properties such as total porosity, pore size distribution as well as air and water conductivity [4]. In other studies, no significant impact of soil compaction on MBC contents was observed [6,7]. ...
... Soil compaction is one of the undesired consequences of using heavy equipment on forest sites, reducing tree growth [1,3] and most likely also affecting soil microbial properties to a largely unknown extent. Compaction has been found to reduce microbial biomass C (MBC) contents in the forest soil [4,5], which has been associated with negative changes in physical soil properties such as total porosity, pore size distribution as well as air and water conductivity [4]. In other studies, no significant impact of soil compaction on MBC contents was observed [6,7]. ...
... However, this increase could not be statistically confirmed. Several studies reported the absence of significant compaction effects on MBC [6,7], whereas many studies reported a compaction-induced decrease in MBC [4,5]. Not only an increased substrate availability but also a lower microbial turnover due to oxygen limitation might be a reason for a re-compaction-induced increase in MBC. ...
Article
Wood harvesting is restricted to a system of permanent skid trails in order to minimize the soil disturbance and damage. Therefore, it is not the compaction of previously undisturbed forest soil, but the re-compaction of already existing skid trails that is of practical relevance when investigating machinery-induced wood harvest effects on soil properties. This study investigated the effects of machinery-induced re-compaction on soil physical, chemical, and microbiological properties of an old skid trail in a spruce forest by wheeling 8 times with a maximum total load of 32.2 Mg, using a genuine old skid trail as a control. Re-compaction significantly increased the bulk density and reduced the porosity, whereas the soil organic carbon (SOC) and total nitrogen (N) contents were not significantly affected. However, re-compaction reduced the SOC/total N ratio by 10%, suggesting considerable SOC mineralization after re-compaction. K2SO4 extractable C contents were increased by 94% at 0–3 cm and 67% at 7–10 cm depth after re-compaction. This led to 20% and 90% increased microbial biomass C/soil organic C (MBC/SOC) ratios at 0–3 cm and at 7–10 cm depth, respectively. In contrast, the ergosterol/MBC ratio was significantly decreased by 10% at 0–3 cm and by about 30% at 7–10 cm depth by re-compaction, apparently due to the promotion of bacteria and mobilization of soil organic matter.
... Moreover, soil compaction indirectly influences tree growth and regeneration due to both physical root damage and reduced soil permeability (Cambi et al. 2018a(Cambi et al. , 2018bJansson and Wasterlund 1999;Mariotti et al. 2020;Sirén et al. 2013;Solgi et al. 2019;Sugai et al. 2020), which may lead to deficiencies of oxygen, water and/or nutrients (Batey 2009;Lee et al. 2020) with recovery processes that may take several decades (Bottinelli et al. 2014;Jourgholami et al. 2020). Rutting and other soil disturbances can also disperse pathogenic fungi, alter microbiological processes (Frey et al. 2009;De Wit et al. 2014;Cambi et al. 2017) and mobilize heavy metals due to the increase in surface water flow (Frey et al. 2009;De Wit et al. 2014;Eklöf et al. 2014). Depending on logging conditions (e.g. ...
... Moreover, soil compaction indirectly influences tree growth and regeneration due to both physical root damage and reduced soil permeability (Cambi et al. 2018a(Cambi et al. , 2018bJansson and Wasterlund 1999;Mariotti et al. 2020;Sirén et al. 2013;Solgi et al. 2019;Sugai et al. 2020), which may lead to deficiencies of oxygen, water and/or nutrients (Batey 2009;Lee et al. 2020) with recovery processes that may take several decades (Bottinelli et al. 2014;Jourgholami et al. 2020). Rutting and other soil disturbances can also disperse pathogenic fungi, alter microbiological processes (Frey et al. 2009;De Wit et al. 2014;Cambi et al. 2017) and mobilize heavy metals due to the increase in surface water flow (Frey et al. 2009;De Wit et al. 2014;Eklöf et al. 2014). Depending on logging conditions (e.g. ...
... This difference negatively affected skidding in terms of risk of soil erosion, being the volume of soil moved higher than forwarding. In fact, the soil displaced by dragged logs and disturbed due to the traffic can be very vulnerable to erosion (Bagheri et al. 2013), causing negative indirect impacts on forest ecosystem, water quality and land stability (Frey et al. 2009); in this way, the measured volumes of bulges can be considered as a reference value of the potential entity of short-time erosion along the trail. ...
Article
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Intensive forestry operations may cause soil compaction, plastic soil disturbances and rutting, which are responsible for undesirable effects on soils, vegetation and water bodies. Despite the numerous studies aimed to identify the main factors affecting soil damages, it still remains unclear whether wood extraction methods and driving direction (uphill or downhill) may affect the impacts of forest machines. This research analyses soil compaction and soil penetration resistance as well as rutting from forwarding and skidding using the same farm tractor in up- and downhill wood extraction. Rutting was estimated by 3D soil reconstruction derived by portable laser scanning (PLS) and close-range photogrammetry using structure for motion (SfM). Our findings showed that the direction of extraction did not affect soil damage severity during forwarding on a 25% slope. On the contrary, in order to reduce soil compaction, downhill skidding is preferable to uphill skidding. The results showed that the pressure on the ground caused by vehicles can be distributed horizontally, thus affecting also the soil between the wheel tracks. The soil bulk density inside the tracks after 10 forwarding passes increased by 40% and with 23% between the wheel tracks. The soil displacement in skidding trails (7.36 m³ per 100 m of trail) was significantly higher than in forwarding (1.68 m³ per 100 m of trail). The rutting estimation showed no significant difference between the PLS and SfM methods, even comparing the two digital surface models (DSMs) obtained, even if photogrammetry was preferred for technical and practical reasons.
... The degree of soil compaction is related to soil texture ), soil moisture (Froehlich and McNabb 1983), harvesting system (Adams and Froehlich 1984), amount of slash on the soil surface (Han et al. 2006;McMahon and Evanson 1994;Wronski 1980), and the number of machine passes (Han et al. 2006;McDonald and Seixas 1997;Soane 1986). Concerns about the effects of compaction extend to reductions in vegetation and root growth, nutrient cycling, and microbial functions (Bodelier et al. 1996;Cambi et al. 2015;Frey et al. 2009;Startsev and McNabb 2000). ...
... Unfortunately, soil compaction occurs within the first few passes of machinery used for skidding or forwarding during a timber harvest operation (Cambi et al. 2015;Han et al. 2006). After timber harvesting and site preparation operations are complete, the extent of compaction within a harvest unit can range from 10 to 70 percent (Cambi et al. 2015;Frey et al. 2009;Grigal 2000;Picchio et al. 2012). In addition to changing soil physical properties, increased compaction can lead to substantial alterations of soil biological and chemical properties (Cambi et al. 2015), such as less gas exchange and water infiltration, reduced root and tree growth, lowered decomposition, altered nutrient cycling, and a general decline in soil microbes. ...
... Soil porosity is a measure of open spaces between soil particles. Traffic on forest soil can reduce overall porosity up to 60 percent (Ampoorter et al. 2007;Ares et al. 2005;Cambi et al. 2015;Demir et al. 2007;Frey et al. 2009;Pichhio et al. 2012;Solgi and Najafi 2014) and reduce macropores (>0.08 mm) to the size of micropores (<0.08 mm) (Frey et al. 2009;Seixas and McDonald 1997). Total porosity is the sum of micropores and macropores. ...
Technical Report
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Soil productivity is essential to the sustained production of forest ecosystem goods and services. Timber harvests may lead to negative ecological impacts to the soil environment, thus reducing both soil and forest long-term productivity. Impacts caused by timber harvests are site-specific, and soil monitoring at various times post-harvest is critical to understanding both short-and long-term damage. Soil compaction is one of the most important issues that arise from harvest operations because it can alter many soil properties and processes including soil bulk density, gas diffusivity, and water holding capacity. Changes in these factors, and others, can lead to lower plant productivity. Additional impacts from timber harvests include soil displacement, rutting, and puddling (smeared soil pores). Soil and site characteristics influence the degree to which the soil is prone to disturbance, as well as rock-fragment content. Understanding the degree, extent, distribution, and duration of soil disturbance is key to determining how long the impacts may last and whether soil restoration activities are needed. We highlight the literature about long-term soil recovery after timber harvests and review the types of impacts, harvest operation methods, and recovery times.
... Soil compaction appears on the surface by the formation of ruts due to horizontal and vertical displacement of soil (Haas et al., 2016). Under the frequent skidding of the machines, soil particles are rearranged and densified, leading to a severe reduction of porosity and pore connectivity (Bottinelli et al., 2014b;Cambi et al., 2015;Frey et al., 2009;Hamza and Anderson, 2005;Hemmat and Adamchuk, 2008). Through porosity reduction, soil compaction increases soil strength and leads to a reduction in fluid infiltration and gas exchange (Ampoorter et al., 2010;Cambi et al., 2016aCambi et al., , 2015Frey et al., 2011;Servadio et al., 2001). ...
... Although soil compaction and its impact on soil health has been widely studied (Brais and Camiré, 1998;Cardenas et al., 2015;Frey et al., 2009;Herbauts et al., 1996;Sands et al., 1979), the time required for the soil to recover after compaction is mainly documented over short periods (between three and five years). The literature shows contrasting results; Croke et al. (2001) found no significant recovery in the superficial layer for variously textured soils after five years of compaction. ...
Article
Soil compaction, which results from the skidding of heavy machines used in forest operations, can seriously damage forest productivity. Indeed, it alters soil structure, disturbs its physical features and consequently affects gas exchange and biological activities. The impact of compaction on soil health has been widely studied, but less is known about the recovery of soil properties over time. In this study, soil compaction was examined by measuring soil penetration resistance. In order to detect the soil recovery on a multi-decadal scale, a space-for-time substitution approach was implemented. Two soil types from the Compiègne forest (Northern France) were investigated (i.e. Luvisol and Podzol). Heavy machine trails of compaction were selected and dated using LIDAR outcomes (Light Detection and Ranging), management documents and aerial photographs. A chronosequence for each soil type was created: 0, 10, 24 and 45 years for the Luvisol and 0, 2, 8, 13 and 23 years for the Podzol. A total of 432 penetration resistance profiles of 30 cm depth were performed in the ruts, as compacted soil, and beside the ruts in undisturbed soils, as control. Penetration resistance was significantly higher in compacted soils in comparison to control soils; it was also higher in the Luvisol than in the Podzol. A linear model with second-order polynomial relationship was used to test the interactions between the penetration resistance, the depth, the situation (compacted versus undisturbed) and the age of compaction. Variance partitioning showed that penetration resistance was mainly controlled by depth, followed by compaction and compaction age, and finally by soil type. The model showed a recovery trend over time as a decrease of the penetration resistance, and a recovery dynamic from the surface toward the deeper layers. The predicted duration of the complete recovery was about 54 and 70 years for the Luvisol and Podzol, respectively. This work also infers that sandy neutral soils could recover in less than 20 years, favored by soil biological activities.
...  Zwar stellen zahlreiche Studien neben der bodenphysikalischen Strukturstörung des Bodens eine Beeinträchtigung der bodenbiologischen und -chemischen Eigenschaften fest (Ebrecht 2005;Frey et al. 2009;Hartmann et al. 2014;Makineci et al. 2007;Tan et al. 2008 ...
... and Frey et al. (2009). They found a strong shift of the microbial community towards taxa with anaerobic metabolism in severely affected wheel tracks. ...
... Soil compaction changes relative proportions of water and air volumes in soil (Brussaard and van Faassen, 1994), leading to reduced oxygen and water availability to roots and microorganisms (Bodelier et al., 1996;Startsev and McNabb, 2000;Frey et al., 2009). Tree physiology and growth may be influenced by these substantial changes of soil environment, so that forest productivity and ecosystem functions are affected (Hartmann et al., 2014;Cambi et al., 2015). ...
... Soil microbial activity is also related to nutritional availability to plants (Jacoby et al., 2017). Unfavorable soil conditions due to soil compaction may change the total bacterial community structures (Frey et al., 2009). Especially, negative effects on ectomycorrhizal species were found in compacted soils (Hartmann et al., 2014). ...
Article
A main disadvantage of heavy machinery in forest operation is soil compaction. Compacted soils may be a barrier to seedling growth, even though the exact mechanisms of action are not clear yet, especially for different soil textures, plant species and ages. Previous meta-analyses did not find significant effects, mostly due to the limited size of their databases. We analyzed 45 articles for above-ground and below-ground morphological traits and 17 articles for physiological traits, and found significant declines following soil compaction. Declines were higher at below-ground than above-ground traits, in younger (< 2-year-old) than older plants (2 to 20-year-old), in pots than in the field, and increased from the coarse-textured Arenic soils to the finer-textured Loamic or Siltic soils. Data from Clayic soils were insufficient for this analysis. More studies on older plants are also recommended. Responses of conifers and broadleaf species were similar. Our findings suggest that the shorter main roots developed due to soil compaction reduce water uptake and thus photosynthesis and the overall plant physiological performance. No significant changes of nitrogen availability to plants were detected. These results could help a successful seedling regeneration after forest operations.
... Changes in the density of the soil and the associated effects on air, heat, and water regimes affect soil organisms and plants and can also have negative effects on the ecological state of soils and future forest productivity [15,52,68]. For example, a common cause of poor plant growth is a reduction in the levels of plant-available nutrients [9,15,30]. Increasing the bulk density of the soil reduces its pore size, water permeability, and gas exchange rates, which in turn reduces the available moisture content. All these factors affect root system formation and plant growth [66,93]. ...
... For example, there are decreases in the abundance and activity of earthworms and in the biodiversity and abundance of microarthropods [8,9]. Soil compaction significantly reduces microbial biomass and microbial activity [30] due to negative changes in total porosity, pore size and bond distribution [104]. ...
Article
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Public opinion has become increasingly critical of current logging methods and technologies, and there is a demand for standards to guide the operations of environmentally impactful industries. For many years, numerous researchers have studied the impact of logging on forest soils, revealing that there is a high risk of damaging forest soil during forest operations and terrain transport. Here we analyse and review a total of 105 publications in this area. This large body of work demonstrates the scientific interest that this field has attracted. Despite this, important areas of uncertainty concerning the impact of forest harvesting still remain. In particular, changes in soil conditions can affect soil properties in ways that are not well understood, with possible impacts on the physical, chemical, and biological properties of soils as well as the structure of the soil cover. While it is difficult to fully eliminate the negative impact of forest operations on forest soils, their adverse environmental consequences should be minimised because soil plays a vital role in tree regeneration and helps determine the productivity of future forest stands. Some of the most frequently cited measures and effective technological solutions to minimize damage to forest soils involve taking terrain and different technical solutions into account when organising logging operations. Potentially helpful technical solutions include selecting machines and mechanisms suitable for the site conditions, using larger and/or low-pressure tyres, using tyre pressure control, using anti-skid tracks, using track belts, meliorating wet areas, and using logging machinery incorporating global positioning systems and geographic information systems. Planning measures that can help minimize soil damage include choosing a suitable wood harvesting system and technology, accounting for seasonal factors when planning logging operations, planning networks of roads and trails in advance, leaving wood residues or mats on soil surface, training forest specialists, and reducing the number of machine passes over skid trails and strip roads. Despite active interest in applying sparing methods of wood harvesting, uptake of measures designed to reduce negative impacts on forest soils after logging has been limited. This may be due to a lack of scientific and technical information and the high cost of implementing best management practices. Moreover, economic factors and production plans may require wood harvesting throughout the year, irrespective of conditions. For citation: Ilintsev A.S., Nakvasina E.N., Högbom L. Methods of Protection Forest Soils during Logging Operations (Review). Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 5, pp. 92–116. DOI: 10.37482/0536-1036-2021-5-92-116
... One typical impact of forestry machines on soil properties is soil compaction (Greacen and Sands 1980;Kumakura et al. 1994;Ampoorter et al. 2007Ampoorter et al. , 2012Allman et al. 2015;Dinis et al. 2015), which decreases the soil nitrogen (N) availability (Breland and Hansen 1996;Jensen et al. 1996a;Tan et al. 2005;Jennings et al. 2012). Many studies have also indicated that soil compaction causes a deficiency of oxygen in the soil due to the decreased soil pore volume and continuity reducing the soil air/water permeability and increasing soil water retention (Jensen et al. 1996a;Tan et al. 2005;Frey et al. 2009;Goutal et al. 2013;Cambi et al. 2015). This, in turn, induces a decrease in microbial biomass and activity (Jensen et al. 1996a;Tan et al. 2005;Frey et al. 2009), resulting in a decrease in the net N mineralization rate (hereafter referred to as the soil N mineralization rate). ...
... Many studies have also indicated that soil compaction causes a deficiency of oxygen in the soil due to the decreased soil pore volume and continuity reducing the soil air/water permeability and increasing soil water retention (Jensen et al. 1996a;Tan et al. 2005;Frey et al. 2009;Goutal et al. 2013;Cambi et al. 2015). This, in turn, induces a decrease in microbial biomass and activity (Jensen et al. 1996a;Tan et al. 2005;Frey et al. 2009), resulting in a decrease in the net N mineralization rate (hereafter referred to as the soil N mineralization rate). Nitrogen is the most important element regulating tree growth in a lot of terrestrial ecosystems (Vitousek and Howarth 1991), and soil N mineralization rate is positively related with forest productivity (Reich et al. 1997). ...
Article
Full-text available
The use of heavy forestry machines for clear-cutting and site preparation causes soil compaction, which can decrease forest productivity. This process becomes complicated in forests with high levels of precipitation due to the erosion and deposition of surface soil. Here, we investigated how soil compaction and slash dispersal on compacted soil affect soil nitrogen (N) mineralization in a high precipitation area with erodible volcanic soil in southern Japan. The physical and chemical properties of the soil were measured inside and outside the ruts of work roads in the presence and absence of dispersed slash in three Cryptomeria japonica plantations 9–10 months after clear-cutting and site preparation. We found that the soil N mineralization rate, particularly the soil nitrification rate, was lower in compacted soil, but the dispersal of slash after soil compaction enhanced the soil N mineralization and nitrification rates. Soil compaction also led to a low soil water permeability and high volumetric soil water content and was associated with the erosion and deposition of surface soil, with soil deposition including organic matter, being observed under dispersed slash. Additionally, the soil carbon (C) and N concentrations were lower in compacted soil but improved under dispersed slash. Principal component analysis showed that soil compaction and the soil C and N concentrations were closely related to each other on the first principal component (PC1), while the soil C/N ratio was separated from other factors on PC2. Furthermore, the scores of both PC1 and PC2 were related to soil N mineralization. These results suggest that soil compaction by forestry machines has a negative impact on soil N mineralization under high precipitation, but slash dispersal on the compacted soil is an effective approach for maintaining the soil N mineralization. The soil C/N ratio is likely related with N mineralization in the impacted soils, but the negative relationship between soil compaction and soil C and N concentrations through the movement of surface soil containing these elements should also be considered to fully understand the changes in soil N mineralization that occurs in forests under high precipitation.
... Figure 1. Physical effects on soil due to compaction (DeJong-Hughes, 2018) Compaction decreases air and water availability to plant roots and microscopic organisms as well (Bodelier et al. 1996;Startsev and McNabb, 2000;Frey et al. 2009). Soil compaction changes soil physical properties and structure, decreases pore space and saturated hydraulic conductivity (Jansson and Johansson, 1998;Grace et al. 2006), and affects site quality by reducing the rate of water penetration and aeration of soil, and can increase resistance to root penetration (Greacen and Sands,1980;Taylor & Brar 1991;Quesnel and Curran, 2000;Grigal 2000;Zhao et al. 2010) and can eventually restrict plant growth (Kozlowski, 1999;Meyer et al. 2014). ...
Article
Harvesting during winter is encouraged as a best management practice to protect soil during logging operations. The western Upper Peninsula of Michigan typically experiences early and persistent snowfall, which insulates the forest floor and prevents soils from freezing. The objective of this study is to assess the effects of slash volume, snow depth, overstory treatment, and machine traffic intensity on soil bulk density following a winter harvest of a northern hardwood forest on cobbly silt-loam soils. The harvest was conducted at the Ford Forest in Alberta, Michigan using cut-to-length harvest systems (i.e. harvester and forwarder) during which the soil remained unfrozen. Four levels of machine traffic (high, medium, low, none) and two levels of overstory treatment (clear-cut and partial cut) were considered within a factorial experimental design. Samples were extracted using coring cylinders and separated into three depths (0-5, 5-10, 10-20 cm) prior to drying, sifting and weighing. Results indicate that bulk density did not differ between the no traffic treatment and low traffic treatment at the 0-5 cm depth. However, soil bulk density for the no-traffic treatment was significantly lower than soil bulk density for the medium and high traffic treatments at the 0-5 cm depth. There was a significant effect for traffic in all depths, fine and full soil, except for the 5-10 fine and full soil (which had a p-value of .06). No significant effects of slash volume or snow depth were detected but there was significant effect of percent rock at each depth.
... The degree of compaction in the wheel tracks and areas adjacent to the tracks is large when compared to the areas where no trafficking took place. The strong adverse effect of increasing slope of the skid trail on bulk density and porosity is likely a consequence of the difficulties in skidding on steep terrain where machine wheels can slip, pushing soil particles closer together (Frey et al., 2009), and increased topsoil vibration due to lower speed on steeper slope results in more severely disturbed soils compared to flat terrain Naghdi and Solgi, 2014;Williamson and Neilsen, 2000) through enhanced soil puddling, churning or displacement (Gayoso and Iroume, 1991). Further, changes in machine weight distributions toward the rear axle when driving uphill in steeper terrain means that the rear axle carries a greater load, resulting in greater ground pressure for the same load compared to flat terrain. ...
... Negative impacts of forest compaction include decreased soil porosity (Lenhard 1986, Ampoorter et al. 2007), decreased water infiltration and permeability (Currie 1984, Arthur et al. 2013, increased runoff (Startsev and McNabb 2000, Croke et al. 2001, Christopher and Visser 2007, decreased air permeability and oxygen supply (Frey et al. 2009), decreased root growth (Qi et al. 1994, Whalley et al. 1995, Gaertig et al. 2002, and decreased tree growth (Ares et al. 2005, Blouin et al. 2005, Demir et al. 2010, which in turn can reduce stand productivity (Labelle and Jaeger 2011). ...
Article
Cable-assisted (or tethered) mechanized harvesting has recently been introduced to the Pacific Northwest of the United States, and is rapidly being adopted by the forest industry. However, potential environmental impacts, productivity and cost of the new harvesting systems have not been well-assessed. This study aims to examine the effects of cable assistance on soil compaction, system productivity and cost through a field-based experiment. A harvester-forwarder system was used to thin a harvest unit on dry soils in western Oregon, with and without cable-assistance. We conducted a detailed time study during operations and collected soil measurements before and after machine passes. Machine productivity ranged from 28.75 to 92.36 m3 per scheduled machine hour, with resulting unit costs for untethered and tethered systems ranging from $13.19 to $18.13/m3. Our results showed reduced soil impacts in both extent and degree of soil compaction when cable assistance was employed. The reduced extent of soil impacts is attributed to a reduction in track wander owing to the operative tensions of the tether cable, and the smaller increase in soil density appears to be attributed to combined effects of initially denser soil conditions and reduced shear displacement as a result of cable-assistance.
... Results confirm that machine-induced soil disturbance and compaction lead to the reduction, and in some instances, complete removal of the litter layer that has a key role in maintaining soil quality as reported in previous studies (Sayer 2006, Stuart and Edwards 2006, Jodaugiene et al. 2010, Cambi et al. 2015, Jordán et al. 2010, Lombao et al. 2015. The removal of the litter layer can cause decreased food source, altered microclimate of surface soil, and decreased populations of soil fauna, which results in a decrease of soil porosity and aeration (Sayer 2006, Mulumba and Lal 2008, Frey et al. 2009, Majnounian and Jourgholami 2013. Six years after applying the reclamation treatments, the SM and WDS treatments showed that values of the tested soil chemical properties differed from the values of the corresponding UND area (acting as control). ...
Article
Full-text available
Several rehabilitation treatments have been applied to mitigate runoff and sediment in machine trafficked areas following logging operations, while the knowledge on the consequence of these remediation techniques on the recovery of soil properties remains scarce. The objective of the study was to determine the effect of different rehabilitation treatments including sawdust mulch (SM), water diversion structure (WDS), untreated/bare trail (U), and undisturbed or control area (UND) on the recovery of soil chemical properties over a six-year period after machine-induced compaction occurred on three longitudinal trail gradients (10, 20, and 30 %).In each treatment, the following soil properties were measured: litter thickness, pH, EC, soil organic C, total N, and available P, K, Ca, and Mg. Five sampling plots (with 10 m length and 4 m width) were positioned in each trail gradient classes and three of these plots were randomly considered for soil sampling.The results demonstrate that litter thickness differed among the three treatments, with the highest amount present on the UND area and lowest on the U treatment. Meanwhile, the highest pH (6.75), EC (0.21 Ds m−1), N (0.27 %), available P (14.61 mg kg−1), available K (123.5 mg kg−1), available Ca (135.1 mg kg−1), and available Mg (42.1 mg kg−1) and the lowest C (1.21 %) and C/N ratio (7.83 %) were found on the SM with gradient of 10 % compared to other gradient classes on SM, WDS and, U treatments. The recovery value of litter depth, pH, EC, C, N, C/N ratio, and available nutrients (P, K, Ca, and Mg) were higher on the SM than the WDS at the gradient of 10 %, while significantly higher levels of these variables were measured under WDS installed on trail gradients of 30 % and 20 % when compared with the same gradients on SM. Results of the study revealed that soil chemical properties showed some evidence of recovery following SM and WDS rehabilitation treatments compared to U, although these properties did not fully recover within 6 years as compared to UND area.
... The superfi cial soil layers at 0-10 and 10-20 cm were the most aff ected by the machine traffi c which resulted in macroporosity values that were reduced by 62.50% and 53.84% in the respective soil layers. Frey et al. (2009) also found marked decreases in macroporosity with values ranging from 60 to 53% in several studied soils. Szymczak et al. (2014) reported that the macroporosity in the 0-5 and 5-10 cm layers following wood-harvesting operations was compacted, with reductions between 60% and 50%, respectively, in relation to the initial soil conditions. ...
Article
Full-text available
This study evaluated the compaction of a Bruno Nitisol caused by traffic intensities by a directional feller and skidder used to wood harvesting in a Pinus taeda stand. Data were collected at a forest company located in Parana State, Brazil. Samples were performed using an installation of four blocks (30 × 15 m) with subdivided plots and the treatments included a combination of five traffic simulations of directional feller and skidder machines, with the simulations performed in the plots at four soil depths, referred to as subplots. Compaction was evaluated by soil density, total porosity, microporosity, and macroporosity. The data were submitted to analysis of variance and the means were compared with the Tukey test at a 5% level of significance. Linear regression equations were also adjusted to represent the relation between traffic intensity, depth, and the variable of interest. The results showed that machine traffic caused higher compaction of the superficial soil layers, resulting in a 14.6% increase in soil density compared to the soil subjected to no machine traffic. The increase in traffic intensity of the skidder tractor reduced macroporosity by 62.5% and 53.8% at depths of 0-10 and 10-20 cm, respectively. Dragging of the logs by the skidder tractor increased soil compaction due to the several trips by the machine in a single line.
... The primary consequence of driving with forest machines, is compaction of the forest soil, resulting in a reduction of macro-and fine pores, changes in the distribution of the pores in the soil, and a decrease of soil permeability to water (Halvorson et al. 2003;Cambi et al. 2015). This leads to a change of the water-air relationship and results in a decrease in microbiological activity and declined conditions for plant growth (Rehfuess 1990;Arnup 1999;Frey et al. 2009). As a result, growth rates of trees and seedlings might be reduced and the capability to react to changing environmental conditions might be reduced (Kleibl et al. 2014). ...
Article
Driving forest machines on wet soils causes irreversible soil compaction, often associated with intensive rut formation and inaccessibility of wheeled forest machines for future forest operations. The German forestry equipment manufacturer FHS, Forsttechnik Handel & Service GmbH, engineered a forwarder, the Trac 81/11, equipped with conventional, well-proved bogie-axles embraced by a closed rubber track. At the center of the bogie-axle, four additional supportive rollers are placed to increase the load-carrying section between the tires of the bogie-axle. The study aimed to characterize the principle concept and the trafficability of the forwarder by analyzing the footprint area, the contact pressure, the rut formation on forest sites and the slippage during driving. Therefore, the effective contact area was measured on steel plates and rut formation was analyzed on a case study basis. Results showed that the supportive rollers increase the contact surface area by about 1/3. By this, a decrease of peak loads below the wheels and a more homogenous load distribution were observed. However, the contact surface area is still clearly divided into three parts; the area between the supportive rollers and the wheels does not take any load. Results of the rut formation were diverse: After 20 passes with 26,700 kg total mass, rut depth varied between 12.6 and 212.5 mm. Overall, the new undercarriage concept of FHS demonstrated a generally positive performance. The engineered forwarder contributes to reduce the environmental impact associated with log extraction.
... 23) Die mikrobielle Biomasse des Bodens wird durch Bodenverdichtung negativ beeinflusst (Frey et al., 2009;Pupin et al., 2009) und führte zu einer verringerten Bodenbelüftung (13-36-%ige Abnahme der luftgefüllten Porosität), was zu einer Verringerung des mikrobiellen Biomasse-Kohlenstoffs und des mikrobiellen Biomasse-Stickstoffs führte (Tan & Chang 2007). ...
Preprint
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Zusammenfassung Die offenkundigen Schädigungen der von den Extremwitterungen der vergangenen Jahre betroffenen Wälder geben Anlass zu einer Diskussion, die über die Wahl ökonomisch relevanter Baumarten für zukünftige Pflanzungen weit hinausgehen muss. Es bedarf einer ökosystemaren Perspektive und der Einsicht, dass die Vulnerabilität der Wälder gegenüber dem Klimawandel wesentlich durch den Zustand des Gesamtsystems einschließlich aller Organismen wie etwa Pilze und Mikroorganismen sowie den Zustand der ökologischen Prozesse geprägt werden. Klimasystem und Ökosysteme sind überaus komplex und entziehen sich durch dynamisch neu auftretende Wechselwirkungen sowie Rückkopplungen einer verlässlichen Modellierung. Tatsächlich wurden diverse im Rahmen der globalen Erwärmung auftretenden Phänomene erheblich unterschätzt. Es ist kontraproduktiv und gefährlich, sich ein vermeintlich genaues Bild von der Zukunft zu machen und aus ihm Strategien abzuleiten. Sicher scheint nur, dass die globale Erwärmung noch für längere Zeit voranschreiten wird und zwar in einem Ausmaß, mit einer Durchschnittsgeschwindigkeit und in solche Temperaturbereiche hinein, dass die bevorstehende Situation für die heutigen Ökosysteme als völlig neuartig gelten muss. In jedem Falle ist es in den Wäldern besonders relevant, die auftretenden Störungen bestmöglich abpuffern zu können und damit mehr Zeit für Anpassung bzw. Wandlung zu gewinnen. In Ökosystemen bilden sich durch Diversität und Redundanz ‚Sicherheitsnetze‘; zum anderen werden Puffer und Selbstregulation ausgebildet, die die potenzielle Verwundbarkeit reduzieren. Reife und ungestörte agierende Ökosysteme kennzeichnen sich durch eine ausgeprägte Regulation von Standortbedingungen wie Mikroklima und Wasserspeicherung sowie den fortgesetzten Aufbau des eigenen Substrats – Fähigkeiten, die es zu fördern gilt. Aktuell geschieht in Deutschland großflächig das Gegenteil. Forstliche Akteure agieren– auch im Rahmen von staatlich geförderten Maßnahmen - mit Kahlschlägen, der Befahrung und Räumung großer Flächen. Dies geschieht, ohne dass eine angemessene Abschätzung der Folgen und Risiken für Waldökosysteme, die Biodiversität in Deutschland und die gesamte Umwelt durchgeführt worden wäre. Es besteht Anlass zur Befürchtung, dass die Maßnahmen ganze Landschaftsökosysteme, die Biodiversität und den Naturhaushalt nachhaltig beeinträchtigen und damit nicht mit Biodiversitäts-, Wasser- und Bodenschutzgesetzgebung vereinbar sind. Hitze in der Landschaft ist ein zentrales Problem, dem noch zu wenig Beachtung geschenkt wird. Höhere Temperaturen wirken mehrfach schädlich auf Pflanzen. Neben Hitzestress und der Verringerung der Wasserverfügbarkeit durch Austrocknung des Bodens kommt die austrocknende Wirkung heißer Luft hinzu, wobei der Effekt mit steigender Temperatur nichtlinear zunimmt. Wälder und Forsten, landwirtschaftliche Flächen, Wasser, Siedlungen und industriell genutzte Flächen sind nicht voneinander isoliert zu betrachten, zu beplanen sowie so zu nutzen sind, als wären sie voneinander unabhängig. Eine ökosystembasierte Klimawandelanpassungsstrategie müsste eine entsprechende Integration leisten. Es erscheint dringend geboten, Wald und umgebende Landschaft so zu steuern, dass Kühlung und Wasserrückhaltung zur verbesserten Regeneration und Entwicklung von Wäldern beitragen. Es existieren nach wie vor Freiheitsgrade für die Waldentwicklung mit den in naturnahen Ökosystemen vorhandenen Arten. Die aktuellen Nutzungsformen gehören auf den Prüfstand. In naturnahen und vor allem älteren Laubmischwäldern muss ab sofort ein Einschlagsmoratorium verhängt werden. Dies muss gelten, bis klarer wird, wie die Wälder auf die aktuelle Periode von Extremwitterungen reagieren und wie v.a. unterschiedliche Bewirtschaftungsweisen die Waldvulnerabilität erhöhen. Mittelfristig ist ein Maßnahmenpaket zur Förderung der Waldfunktionalität umzusetzen. In den Nadelbaumforsten muss kurzfristig ein totales Verbot des Kahlschlags jeglicher Größe gelten. Für den Umgang mit Flächen, auf denen Kalamitäten aufgetreten sind, sich verstärken oder auftreten werden, müssen dringend für alle Besitzarten verbindliche Behandlungsrichtlinien verabschiedet werden. Die gesamtökonomische Bilanzierung der Waldbewirtschaftung ist auf ein gänzlich neues Fundament zu stellen. Vor allem muss die Verquickung betriebswirtschaftlicher und volkswirtschaftlicher Aspekte offengelegt werden. Versteckte oder mutmaßliche Kosten sowie Subventionen sind genauso zu identifizieren und darzustellen wie alle Quellen von Schad- und Wertschöpfung – einschließlich aller Ökosystemleistungen, die von Wäldern bereitgestellt werden. Benötigt wird eine ganzheitliche Gemeinwohlbilanzierung des Waldes. Eine Art Flächenprämie für die pauschale Förderung von Waldflächen unabhängig von ihrer Beschaffenheit ist kontraproduktiv. Es darf durch Förderung v.a. keine perversen Anreize zur Ökosystemdegradation wie etwa Kahlschläge und Totholzräumung geben. Aktivitäten zur Waldmehrung sowie biodiversitätsfreundliche Entwicklung von Kalamitätsflächen tragen kurzfristig zur Vermeidung von CO2-Emissionen und zur Bewahrung bzw. Entwicklung weiterer regulierender Ökosystemleistungen bei. Es gibt bereits privatwirtschaftliche Initiativen, die sich zum Ziel gesetzt haben, Besitzer*innen entsprechender Flächen den Zugang zu den entsprechenden Märkten zu ermöglichen und transparente Zertifikate auszustellen. Eine ‚Hitzesteuer‘ für Flächen, die überdurchschnittlich stark zur Erwärmung der Landschaft beitragen, könnte einen Anreiz für Maßnahmen bieten, die den Temperatureffekt eindämmen, sowie Einnahmen für die Förderung von Kühlung generieren. Zu besteuernde Flächen beträfen etwa großflächige Gebäude/Dächer, versiegelte Verkehrsflächen oder Tagebaue. Landnutzende könnte von einer entsprechenden Besteuerung ausgenommen werden, aber als Empfänger der Förderung kühlender Maßnahmen in Frage kommen. Vitale Waldökosysteme könnten so Einkommen generieren, und auf Kalamitätsflächen ergäben sich Anreize dafür, auf radikale Flächenbehandlungen zu verzichten.
... The lowering of chemical parameters seems to be ascribed to the microbiological activity decline [3,53,54] due to displacement of dead wood and forest litter and to mixing and removal of topsoil, coupled with the reduced soil porosity [49]. The lowering of porosity may result in decreased water fluxes and gas diffusion with adverse effects on roots of trees [55,56] and seedlings [57], soil bacterial community [58] and more in general soil biota community [59]. ...
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The Caspian forests of Iran were monitored and evaluated for forest natural regeneration after logging activities for more than a decade. This large area has a substantial ecological, environmental and socio-economic importance. Ground based skidding is the most common logging method in these forests and soil compaction is the most critical consequence of this method. One of the current main topics and important emerging issue in forest research of the last decade are discussed in this study. Soil compaction has major influences on growth and/or mortality rates of forest seedlings. This study has lasted for over ten years so as to have a clear overview related to forest natural regeneration after logging activities. We monitored and evaluated physical soil properties (bulk density, penetration resistance and total porosity) and their effects on maple and beech seedlings on 10-year-old skid trails in the Iranian Caspian forests. Results obtained from evaluating the impact of skid trails within the aforementioned three soil physical parameters were significant; bulk density increased by 12.6% on log skidded routes (between two skidder tires on skid trail) and 36.1% on tire tracks, compared to non-skid trails (1.19 g/cm3), penetration resistance increased by 68% on log skidded routes and 220% on tire tracks, compared to non-skid trails (0.25 MPa), total porosity decreased by 12.8% on log skidded routes and 30.9% on tire tracks, compared to non-skid trails (54%). Among the morphological parameters, lateral root length (LRL) and root penetration depth (RPD) showed the highest decrease at soil compaction compared to the control (decrease in LRL: 60% in maple and 44% in beech; decrease in RPD: 56% in both maple and beech); the main response of growth parameters to soil compaction was found in roots (decrease in dry mass of 36% both in maple and beech); architectural parameters were also influenced by soil compaction, and the response of both seedling species was more evident in the ratio of main root to stem length (RRS) (reduction in RRS 42% in maple, 33% in beech); the ratio of RPD to main root length (RPL) also showed a great reduction (reduction in RPL 20% in maple 33% in beech). Physical soil properties, changes in other environmental properties of skid trails, created differences in beech and maple seedling growth between the skid trails and non-skid trails. This was closely related to the physiological characteristics of the two species studied. Beech seedlings reacted well to a moderate uncovering but they needed little disturbed soil, even if there was a very mixed bedding. Maple seedlings reacted better than beech seedlings to the uncovering and soil disturbance. The effects of the skid trail on morphology, growth and architecture of maple seedlings in the Hyrcanian beech forests showed that the maple, as a seedling, is a suitable species for maintaining the physical properties of skid trails after logging operations in the beech stands in the Caspian forests of Iran.
... Heavy machinery-induced soil compaction mainly causes a reduction in macroporosity responsible for soil aeration and drainage (Frey et al., 2009). Therefore, the use of heavy machinery in the mining areas mainly change the pore characteristics in the soil, which could affect the water transport. ...
Article
The use of heavy machinery during opencast coal mining can result in soil compaction. Severe soil compaction has a negative impact on the transport of water and gas in the soil. In addition, rainfall intensity has traditionally been related to soil surface sealing affecting water transport. To assess the effects of rainfall intensity and compaction on water infiltration and surface runoff in an opencast coal mining area, the disturbed soils from the Antaibao opencast mine in Shanxi Province, China, were collected. Four soil columns with different bulk densities (i.e., 1.4 g cm‐3, 1.5 g cm‐3, 1.6 g cm‐3, and 1.7 g cm‐3) were designed, and each column received water five times at rainfall intensities of 23.12, 28.91, 38.54, 57.81, and 115.62 mm h‐1. The total volume of runoff, the time to start runoff, and the volumetric water contents at the depths of 5 cm, 15 cm, 25 cm, 35 cm, 45 cm, 55 cm, and 65 cm were measured. Under the same soil bulk density, high rainfall intensity reduced infiltration, increased surface runoff and decreased the magnitude of change in the volumetric water contents at different depths. Under the same rainfall intensity, the soil column with a high bulk density showed relatively low water infiltration. Treatments 3 (1.6 g cm‐3) and 4 (1.7 g cm‐3) had very small changes in volumetric water contents of the profiles even under a lower rainfall intensity. Severe soil compaction was highly prone to surface runoff after rainfall. Engineering and revegetation measures are available to improve compacted soil quality in dumps. Our results provide a theoretical basis for the management of land reclamation in opencast coal mine areas.
... Soil physical degradation processes like compaction and shearing change the relations between soil particles and pore space and committing the water and air movement through the soil. Root growth and soil microbial communities are severely affected by transmission of water and air (Frey et al. 2009). Microbial processes in soil are known to be heavily dependent on the physical pore structure that influences microbial habitats (Marshall 2000). ...
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Microorganisms play essential roles in regulating the ecosystem. Several interactions occur between plants and their associated rhizobacteria, cyanobacteria, and/or mycorrhizal fungi, which result in better plant growth. This chapter presents general aspects regarding interactions between edaphoclimatic conditions and plant–microbial inoculants and their impacts on plant growth, nutrient uptake, and yields. The different roles of the arbuscular mycorrhiza fungi (AMF) and plant-growth-promoting microbes (PGPM) are highlighted. Although the presented data demonstrated the remarkable abilities of these microorganisms, there is still much to be done on both explorations as well as the implementation of PGPM. Single microorganism inoculants, as well as formulations, have been proved to significantly increase crop production at a very low cost when compared to chemical fertilizers. Exploration that involves the understanding of the mechanism and at the same time implementation needs to take care of a great deal of optimization on field applications.
... In the last decades, the use of heavy machinery for logging operations has increased in forest and agroforestry sectors due to their high productivity rate (Picchio et al. 2012Cambi et al. 2016). The use of heavy machines can have detrimental effects on forest soils with the potential to contribute to soil physical degradation, which results in an increase in soil bulk density, penetration resistance and shear strength (Williamson and Neilsen 2000), decrease in soil macroporosity (Berli et al. 2004;Frey et al. 2009;Solgi et al. 2015;Nikooy et al. 2020), and decrease in connectivity of pores (Picchio et al. 2012). The physical, chemical, and biological properties of the forest soil change as a result of harvesting operations, and this is commonly named as soil disturbance ). ...
Article
Poplar plantations have been widely practiced in the coastal area of the Caspian Sea in northern Iran. In this research, soil compaction following logging operations carried out by wheeled cable skidder was investigated in two poplar plantations with different characteristics including moist soil and dry soil. The soil gravimetric moisture content (MC) in the dry site ranged from 13% to 14.4%, while in the moist site it ranged from 30.5% to 34.6%. The mineral soil samples were collected from the skid trails in both sites. The impact of skidding operations on soil layers (soil depth, SD) was examined by measuring rut depth (RD), penetration resistance (PR), bulk density (BD), and total porosity (TP) at five traffic intensities (TI). Results indicated that MC and TI had a significant effect on RD, PR, BD, and TP; however, SD had a significant effect on PR and BD. The values of BD were significantly higher in the moist site than in the dry site, while the values of PR and TP were significantly higher in the dry site than in the moist site. The RD in the moist site (11.7 cm) was 1.65 times more than RD in the dry site (7.1 cm) after one pass where a pass was defined as one empty and one loaded trip over a spot. The differences between BD after 10 and 15 passes were not significant on the dry site, but significant in the moist site. We concluded that skidding operations should be conducted when soil conditions are dry. ARTICLE HISTORY
... Die mikrobielle Biomasse des Bodens wird durch Bodenverdichtung negativ beeinflusst (Frey et al. 2009;Pupin et al. 2009) und führte zu einer verringerten Bodenbelüftung (13-36-%ige Abnahme der luftgefüllten Porosität), was zu einer Verringerung des mikrobiellen Biomasse-Kohlenstoffs und des mikrobiellen Biomasse-Stickstoffs führte (Tan & Chang 2007). ...
Technical Report
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Das vorgelegte Förderkonzept beruht darauf, dass auf Grundlage von ausgewählten Indikatoren, tatsächlich existierende ökosystemare Funktionen und Leistungen in Form von (monetären) Prämien gefördert werden können. Folgende Indikatoren wurden als Proxy-Variablen für die Gemeinwohlleistungen der Wälder vorgeschlagen: Kühlungsprämie, Vitalitätsprämie, Biomasseprämie und Strukturvielfaltsprämie. Die benötigten Daten werden durch jährlich überprüfbaren Fernerkundungsdaten erhoben.
... Also, the soil availability of N tends to decrease due to the lower organic N concentration in the soil. Our results were consistent with those found in other silvicultural management studies, where a reduction in organic residues was accompanied by reductions in microbial biomass, SOC, and nutrient availability (Frey et al. 2009, Scott et al. 2014, Achat et al. 2015a, Foote et al. 2015, Colombo et al. 2016. ...
Article
Sustainable silvicultural management requires the maintenance of long-term ecosystem processes. We used the CENTURY model to simulate the impact of wood extraction and organic amendments on aboveground biomass, carbon (C) storage, and the availability of nitrogen (N) in the two dominant silvicultural methods in Mexico: the silvicultural development method (SDM) and irregular forest management (IFM). The values of the mean absolute percentage error for the SDM and IFM were 2.1% and 3.3% for C in aboveground biomass, 5.7% and 5.0% for soil organic carbon (SOC), and 14.9% and 21.6% for N, respectively. Simulation for the SDM (1967–2068) suggested a reduction of ~7% in C in soil, microbial biomass, and litter, 9% in aboveground biomass C, and ~20% in the mineral N available. For IFM, the simulation (2009–2019) suggested a reduction of 14% in the accumulation of aboveground biomass and 13% in the mineral N available. Simulation of the adoption of management practices suggested that N mineral availability would increase by 2%–3% without drastically reducing the SOC, improving aboveground biomass production by ~7%, in each management system. Study Implications In Mexico, current silvicultural management is causing alterations in the biological and chemical processes of the soil, but the future impacts on the production of forest wood and loss of fertility cannot be estimated by direct measurements. We simulated two silvicultural management alternatives with two rotation cycles and measured the response in terms of SOC, nitrogen availability, and aboveground biomass. The model shows that improving forest residue management by adding organic amendments to the soil would counteract changes in soil microbial activity, nitrogen availability, SOC, and aboveground biomass in the future. Managers should consider this information to reorient current crop residue management to achieve the objectives and the sustainability of forest management in Mexican temperate forests.
... Considering that the microbiological population and indices are affected the most against all these changes in forest ecosystems, and microbiological soil properties can be used as indicators about changes in an ecosystem (Wardle 1992;Jordan et al. 2003;Frey et al. 2009). ...
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Harvesting activities in forests can seriously damage soils and cause short and long-term changes in some of their properties. The aim of this study is to determine the effects on the microbial properties of the failure of the soil by the whole tree method using a farm tractor in the short term in the Turkish red-pine forests of Kahramanmaraş Forestry Operations Directorate in Başkonuş Forest Enterprise Chief. In total, 72 soil samples were collected on two soil layers (0-10 and 10-20 cm) and three seasons (spring, summer, and autumn) for identifying some physicochemical and microbial properties of soil. Mean values of the soil organic carbon and nitrogen were statistically different in the skidding (2.15% - 0.13%) and control (2.90% - 0.16%) areas, respectively. Also, It was determined that the skidding activities had a statistically significant effect on the microbial biomass carbon, nitrogen, and microbial soil respiration. A significant reduction in organic carbon and microbial biomass was observed in the soils in the skidding line. According to the seasonal patterns, the microbial biomass of the samples was found the lowest in summer (657.17 μg g–1) and the highest (763.76 μg g–1) in autumn. In the control areas, the lowest was 773.99 μg g–1 in the spring season and the highest was 886 μg g– 1 in the autumn season. It is predicted that the decomposition rate may have increased in parallel with the soil temperature, which increases as a result of the removal of the litter layer from the soil surface to any other places in the harvesting application. Consequently, it is important for forest and soil health to monitor the changes in the microbiological characteristics of soils for long periods and to produce in a way that causes minimum damage to the soil in harvesting activities of forests. Therefore, harvesting activities should be carried out in periods when the soil is hard. In seasons, when soils are soft and sensitive, there is a need to develop alternative harvesting methods such as aerial yarding systems from stump to landing instead of skidding.
... The degradation of soil leads to the decline in total soil porosity, decrease in soil macro-porosity, reduce spore connectivity, increases shear strength and soil density (Solgi et al. 2013). The compaction of soil can lead to a decline in exchangeable gasses through the atmosphere and movement of water and gases via the soil, accordingly reducing nutrients, water, and oxygen to the roots (Frey et al. 2009). Decreases in soil porosity and air permeability decrease the extension and root penetration roots and consequently decrease the accessibility of roots to the uptake of water and nutrients (Botta et al. 2007). ...
Article
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Heavy forest machinery used in skidding has the capacity to influence the physical properties of soils. These may possibly lead to an upsurge in soil disruption and compaction of the soil surface decreases forest soil fertilities. This study assesses the effects of skidding on some soil physical properties such as the soil bulk density and porosity in the Nkrankwanta off-forest reserve in Ghana. The treatments comprised of four traffic intensity levels (1, 5, 10, and 15 passes) of the Mercedes Benz skidder (MB) Trac 1800 and a slope of two levels (less than 20 % and greater than 20 %) in a completely randomized block design. In addition, porosity and soil bulk density were assessed at varied distances from the MB Trac 1800. Soil bulk density results showed increasing trends with traffic frequency. Soil bulk density measured in the undisturbed area was 0.64 g cm-3 and 0.56 g cm-3 at slopes of less than 20% and greater than 20%, respectively. On the skid trail, soil bulk density significantly increased with traffic frequency (p<0.05). However soil porosity declined. Soil porosity estimated in uninterrupted area was 59.10 % and 57.40 % at < 20% and > 20% slope, respectively. Soil porosity was significantly influenced via different skidder passes (p<0.05). The soil physical properties were not influenced by the steepness of the slope however acted together in the number of passes to influence soil porosity. The impacts of the skidder on soil physical properties were significantly apparent at distances of 2 m to each sideway of the skidding trail. In conclusion, distinct responsiveness ought to be considered throughout the operations of skidding to curtail unfriendly influences on soil physical properties in ground-base skidding.
... Methodological constraints have, however, long limited our ability to characterize soil microbial diversity. Changes in microbial diversity due to compaction have previously been assessed using techniques, such as phospholipid fatty acids or terminal restriction fragment length polymorphism analyses that provide compositional information at a relatively coarse level of resolution, and without much power for taxonomic identification of the responsive groups [27,28]. Recent studies have harnessed the potential of high-throughput DNA sequencing technologies to assess the resilience of soil microbial communities to soil compaction in forest ecosystems [25,29]. ...
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Soil compaction affects many soil functions, but we have little information on the resistance and resilience of soil microorganisms to this disturbance. Here, we present data on the response of soil microbial diversity to a single compaction event and its temporal evolution under different agricultural management systems during four growing seasons. Crop yield was reduced (up to −90%) in the first two seasons after compaction, but mostly recovered in subsequent seasons. Soil compaction increased soil bulk density (+15%), and decreased air permeability (−94%) and gas diffusion (−59%), and those properties did not fully recover within four growing seasons. Soil compaction induced cropping system-dependent shifts in microbial community structures with little resilience over the four growing seasons. Microbial taxa sensitive to soil compaction were detected in all major phyla. Overall, anaerobic prokaryotes and saprotrophic fungi increased in compacted soils, whereas aerobic prokaryotes and plant-associated fungi were mostly negatively affected. Most measured properties showed large spatial variability across the replicated blocks, demonstrating the dependence of compaction effects on initial conditions. This study demonstrates that soil compaction is a disturbance that can have long-lasting effects on soil properties and soil microorganisms, but those effects are not necessarily aligned with changes in crop yield.
... This was in contrast to the effect of increasing soil moisture, which resulted in declining cell numbers, an effect that was explained by increasing oxygen limitation (Postma and van Veen, 1990). Frey et al. (2009) observed changes in bacterial community structure in severely compacted forest soils (32% higher bulk density) and related this to reduced air and water conductivities. In a study by Liu et al. (2017), compaction negatively affected soil physical properties, but the latter had little effect on N 2 O-related microbial community size as it was correlated only to a few microbial gene abundances. ...
Article
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Nitrous oxide (N 2 O) is the contributor to agricultural greenhouse gas emissions with the highest warming global potential. It is widely recognised that traffic and animal-induced compaction can lead to an increased potential for N 2 O emissions by decreasing soil oxygen supply. The extent to which the spatial and temporal variability of N 2 O emissions can be explained by soil compaction is unclear. This review aims to comprehensively discuss soil compaction effects on N 2 O emissions, and to understand how compaction may promote N 2 O emission hotspots and hot moments. An impact factor of N 2 O emissions due to compaction was calculated for each selected study; compaction effects were evaluated separately for croplands, grasslands and forest lands. Topsoil compaction was found to increase N 2 O emissions by 1.3 to 42 times across sites and land uses. Large impact factors were especially reported for cropland and grassland soils when topsoil compaction—induced by field traffic and/or grazing—is combined with nitrogen input from fertiliser or urine. Little is known about the contribution of subsoil compaction to N 2 O emissions. Water-filled pore space is the most common water metric used to explain N 2 O emission variability, but gas diffusivity is a parameter with higher prediction potential. Microbial community composition may be less critical than the soil environment for N 2 O emissions, and there is a need for comprehensive studies on association between environmental drivers and soil compaction. Lack of knowledge about the interacting factors causing N 2 O accumulation in compacted soils, at different degrees of compactness and across different spatial scales, limits the identification of high-risk areas and development of efficient mitigation strategies. Soil compaction mitigation strategies that aim to loosen the soil and recover pore system functionality, in combination with other agricultural management practices to regulate N 2 O emission, should be evaluated for their effectiveness across different agro-climatic conditions and scales.
... Soil physical degradation processes like compaction and shearing change the relations between soil particles and pore space and committing the water and air movement through the soil. Root growth and soil microbial communities are severely affected by transmission of water and air (Frey et al. 2009). Microbial processes in soil are known to be heavily dependent on the physical pore structure that influences microbial habitats (Marshall 2000). ...
Chapter
The proceedings include the Johanna Döbereiner memorial lecture, a note on the discovery in 1965 of inorganic nitrogen complexes, the keynote address, and 68 papers in 15 sections (each mostly introduced by an overview): Chemistry and biochemistry of nitrogenase; Bacterial genomics; Plant genomics; Signal transduction; Developmental biology; Signals in the soil; Proteins in regulation and development; Stresses and factors limiting nitrogen fixation; Regulation of N 2 fixation and metabolism; Nodule metabolism; Endophytic/associative plant-microbe interactions; Common themes in symbiosis and pathogenesis; Nitrification, denitrification and the nitrogen cycle; Novel applications in nitrogen fixation; and Applied aspects of nitrogen fixation. Abstracts of poster presentations, and author and subject indexes are also included.
... Although soil disturbance due to mechanical site preparation and its impact on soil health have been widely studied (Brais and Camiré, 1998;Frey et al., 2009;Herbauts et al., 1996;Sands et al., 1979), the time required for the soil to recover after disturbance has mainly been documented over short periods (between three and five years). The recovery time for both physical and biological properties is highly variable because it directly depends on several site-related factors such as terrain slope, texture, pedoclimate, soil organic matter, biomass and biotic activity (Zenner et al., 2007). ...
Article
The projected increase in the worldwide demand for forest products over the coming decades may lead to more intensive forest management. This will involve extension of the area of planted forests, increased mechanization and greater pressure to extract timber from sensitive zones such as steep slopes, wet and heavy soils. However, such intensification may place soil protection and ecosystem services provided by forests at risk. In this study, the impacts of mechanized forest site preparation (shearing and ripping) and manual site preparation were evaluated during the first 2.5 years and 15 years after plantation establishment in a soil susceptible to erosion and compaction in a temperate humid climate. Site productivity, soil carbon storage, soil fertility, soil hydrological properties and protection against erosion and run-off were evaluated as ecosystem services provided by forest soils. Soil loss due to manual site preparation was 25 g m⁻² yr⁻¹, while annual soil loss ranged from 98 to 3128 g m⁻² in sheared sites and from 345 to 4652 g m⁻² in ripped sites. However, soil loss was negligible 2.5 years after site preparation. By contrast, soil compaction persisted during 15 years and was significantly higher in mechanically prepared plots than in manually prepared plots. The changes in soil water holding capacity persisted 15 years after site preparation. The available water content was significantly lower in mechanically prepared plots (by shearing and ripping) than in manually prepared plots. During the period 2002–2004, tree height was between 13 and 52 % higher in manually prepared sites than in sheared sites, while in ripped sites tree height was between 91 % higher and 62 % lower than in the manually prepared plots. However, no significant differences in tree height were observed 15 years after site preparation. By contrast, significant differences in the quadratic mean diameter of trees were observed 15 years after site preparation, with tree volumes being highest in manually prepared plots. The findings show that manual site preparation preserves forest ecosystem services such as site productivity and water regulation and can be considered a means of conserving soil and water and a “climate smart” approach in plantation forestry.
... In terms of soil, forest soils differ from agricultural land soils by their vertical stratification due to forest litter accumulation (Zeller et al. 2007) and lack of recent ploughing. Soil compaction may have a negative effect on tree root system development, especially for tree species with shallow root systems (Mäkinen et al. 2001) and on soil microorganisms (Frey et al. 2009). Furthermore, in general, soils of forests on former agricultural land have a more neutral pH in comparison with soils with a longer forest history (Mańka and Mańka 1994). ...
Article
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Forestry practices such as afforestation of former agricultural lands and early forest thinning are applied in several countries. These management strategies increase wood production potential and expand forest areas. However, knowledge of the impact of these practices on the diversity and resilience of soil fungal communities is scarce. This study investigated soil fungal community composition of young (21–40 years-old) Norway spruce (Picea abies (L.) Karst.) dominated stands located in Latvia and Estonia. The study includes data from 62 sampling sites and 2480 soil cores. Fungal internal transcribed spacer amplicons (ITS1-5.8S-ITS2 rDNA region) of DNA extracted from forest floor and fine soil fractions were sequenced using the PacBio sequencing platform. 3176 quality filtered OTUs were detected, and 73.9% of these were identified as fungi. Fungal community composition was mainly differentiated based on soil pH and sampling site. Regarding former land use, relative abundance of the genus Solicoccozyma was higher in samples from former agricultural sites and some species from genera Cortinarius and Russula were identified as more indicative of particular former land use. Litter saprotrophic fungi and fungi of the genus Thelephora were significantly more highly represented in unmanaged sites than in sites where thinning was performed. In conclusion, differences among soil fungal communities are mainly influenced by soil pH and sampling site. Former land use and management have a significant effect on specific genera of ectomycorrhizal and saprotrophic fungi.
... Changes in soil physical properties following compaction significantly and persistently alter soil microbiota and the associated ecosystem functions such as carbon and nitrogen turnover (Hartmann et al., 2014). In our study, the microbial community structure was sensitive to soil compaction at all 16 sites, which is in agreement with other studies (Frey et al., 2009;Hartmann et al., 2014;Schack-Kirchner et al., 2007). Twelve out of 17 dominant classes had larger relative abundances in the moderate and high DC groups (Fig. 4). ...
Article
Soil microorganisms play a key role in soil physical structure. Soil microbial community structure and functions are in turn affected by soil aggregation or degradation. The objectives of this study were to determine the impact of (1) soil aggregate-size distribution and (2) soil compaction on bacterial community richness and structure under three intensive potato (Solanum tuberosum) cropping systems. In June and July 2014, soil samples were collected at a depth of 0-20 cm from 16 sites in Quebec, Canada. The samples were analyzed for aggregate-size distribution, particle-size distribution, total carbon, total nitrogen, total sulfur, oxalate-extractable potassium and phosphorus, gravimetric moisture content, pH and degree of compactness (DC). Soil bacterial community diversity was assessed by using the high-throughput sequencing Illumina MiSeq platform to target the V6-V8 region of bacterial 16S rRNA gene. Bacterial alpha diversity and community structure were found to be affected by cropping systems. Faith's phylogenetic diversity index and bacterial richness increased with increasing proportions of the 1–0.5 mm and 2–1 mm aggregate-size fractions and micro-aggregates in soils. Redundancy analysis revealed a strong correlation between soil bacterial community structure and soil aggregate-size distribution. Eight of the 27 dominant bacterial classes had a significant relationship with aggregate size fractions >2 mm, 1- 0.5 mm and < 0.1 mm. In addition, the degree of soil compaction had a significant effect on soil bacterial community structure, with 70% of the dominant classes showing greater relative abundance in the moderate and high DC groups than in the low DC group. This research provided a benchmark for bacterial community structure in potato agroecosystems as impacted by soil aggregation and compaction.
... The permeability of the soil to air is also severely affected by compaction. Field studies have shown that after a harvest, if grooves have been created, the permeability to air in the first 5-10 cm becomes reduced between 88% and 96%, while without grooves the reduction is only 50% (Frey et al., 2009). Compaction also affects negatively the size of the mesofauna of the soil (i.e., the little invertebrates that enrich the soil), reducing it to up to 93% if entire trees are extracted jointly with some soil (Battigelli et al., 2004). ...
Article
We present a study of annual forestry harvesting planning considering the risk of compaction generated by the transit of heavy forestry machinery. Soil compaction is a problem that occurs when the soil loses its natural resistance to resist the movement of machinery, causing the soil to be compacted in excess. This compaction generates unwanted effects on both the ecosystem and its economic sustainability. Therefore, when the risk of compaction is considerable, harvest operations must be stopped, complicating the annual plan and incurring in excessive costs to alleviate the situation. To incorporate the risk of compaction into the planning process, it is necessary to incorporate the analysis of the soil's hydrological balance, which combines the effect of rainfall and potential evapotranspiration. This requires analyzing the uncertainty of rainfall regimes, for which we propose a stochastic model under different scenarios. This stochastic model yields better results than the current deterministic methods used by lumber companies. Initially, the model is solved analyzing monthly scenarios. Then, we change to a biweekly model that provides a better representation of the dynamics of the system. While this improves the performance of the model, this new formulation increases the number of scenarios of the stochastic model. To address this complexity, we apply the Progressive Hedging method, which decomposes the problem in scenarios, yielding high-quality solutions in reasonable time.
... Quando florestas nativas na Amazônia foram comparadas a variados sítios de agricultura com solo semelhante, somente o volume de macroporosidade foi considerado ter significância estatística (SOUZA; LEITE; BEUTLER, 2004). Máquinas pesadas podem diminuir a macroporosidade em até 50% com apenas algumas passagens sobre o solo(BOTTINELLI et al., 2014;FREY et al., 2009FREY et al., , 2011SCHÄFFER et al., 2007).O limite crítico para a macroporosidade do solo é de até 10% de volume (DEXTER; HORN; KEMPER, 1988; REICHERT; SUZUKI; REINERT, 2007). Porém, alguns estudos tem demonstrado que uma macroporosidade de 5 a 8% é suficiente para o crescimento da planta (HODGSON; MACLEOD, 1989; SILVA; IMHOFF; KAY, 2004). ...
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Na floresta tropical amazônica, poucos estudos sobre compactação do solo causado por exploração madeireira foram realizados. Com este intuito, o estudou avaliou o impacto no solo provocados por operações de extração legal de toras no estado do Amazonas, Brasil. A empresa baseia a etapa de extração com as operações subsequentes de guinchamento e arraste (sistema de colheita Celos). Os dados sobre o impacto no solo foram coletados por amostragem sistemática nas trilhas de arraste durante o tráfego de máquinas e nas áreas controles (sem movimentação de maquinas) localizadas a 10 m das margens das trilhas. Os dados foram coletados em número fixo de passagens, sendo na 1ª, 2ª, 3ª e 5ª e acima de 10 passagens. O solo local classificou-se como Latossolo Amarela distrófico. A avaliação do impacto baseou-se nos parâmetros físicos de densidade (Ds) e resistência à penetração (RP) do solo até 20 cm de profundidade. Amostras de solo para Ds foram coletadas com anel volumétrico de 100 cm3 e a para RP utilizando o penetrômetro de impacto Stolf, com um ângulo de cone de 30°. Foram observadas diferenças significativas nas médias das propriedades físicas do solo (Ds e RP) entre o controle e as áreas de guinchamento apenas nas profundidades de 0 a 5 cm (p<0,05), mas o impacto não limita o crescimento das raízes. A construção de trilhas de arraste apresentou diferenças significativas (p<0,05) em relação ao controle após a primeira passagem sob a marca do trator de esteiras, impactando o solo até 20 cm de profundidade nas marcas das esteiras. Entre as marcas das esteiras, observou-se diferença de Ds e RP (p<0,05) na camada superficial de 0-5 cm, gerando impacto comprometedor para o crescimento radicular. Na avaliação do tráfego de máquinas, o maior aumento na compactação ocorreu sob as esteiras do trator D6M após a primeira passagem. Os valores críticos para limitação do crescimento radicular não ocorreram entre as marcas até a segunda passagem do skidder 525B. Após a terceira passagem, o tráfego de máquinas elevou a RP. Concluiu-se no presente estudo que o impacto principal de compactação do sistema Celos foi observado sob as marcas de rodas logo na primeira passagem, mas, de maneira geral, não inibe o crescimento radicular nas trilhas de arraste.
... Following the compaction experiment in 2008, bulk density, total porosity and macro porosity were measured in 0-10 and 20-35 cm depth. A detailed description of the used methodology is given in Frey et al. [35]. In August 2018, soil rings (200 cm 3 ) were taken at Soil Syst. ...
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Forest soil compaction caused by heavy machines can cause ecosystem degradation, reduced site productivity and increased greenhouse gas (GHG) emissions. Recent studies investigating the plant-mediated alleviation of soil compaction with black alder showed promising results (Alnus glutinosa). This study aimed to measure soil recovery and GHG fluxes on machine tracks with and without black alders in North-East Switzerland. In 2008, two machine tracks were created under controlled conditions in a European beech (Fagus sylvatica) stand with a sandy loam texture. Directly after compaction, soil physical parameters were measured on one track while the other track was planted with alders. Initial topsoil bulk density and porosity on the track without alders were 1.52 g cm−3 and 43%, respectively. Ten years later, a decrease in bulk density to 1.23 g cm−3 and an increase in porosity to 57% indicated partial structure recovery. Compared with the untreated machine track, alder had no beneficial impact on soil physical parameters. Elevated cumulative N2O emission (+30%) under alder compared with the untreated track could result from symbiotic nitrogen fixation by alder. Overall, CH4 fluxes were sensitive to the effects of soil trafficking. We conclude that black alder did not promote the recovery of a compacted sandy loam while it had the potential to deteriorate the GHG balance of the investigated forest stand.
... According to their reports, the abundance of fungal fruiting bodies decreased after band-saw operators were replaced with devices equipped with felling heads. The highly negative impact of the pressure of heavy machinery on forest litter layer has been confirmed by Arnolds [91] and Frey [103]. The correlation between heavy machinery use and mushroom abundance decrease is so significant that it is visible to a respondent's naked eye. ...
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Background: Scientists frequently raise the topic of data deficiency related to the abundance and distribution of macrofungi in the context of climate change. Our study is the first detailed documentation on locals' perception of fungal ecology which covers a large mycophilous region of Europe (Mazovia, Poland). Methods: A total of 695 semi-structured interviews were carried out among local informants in 38 localities proportionally distributed throughout the study area (one locality approximately every 30 km). Interview questions concerned fungi species collected, their perceived habitats, and whether any changes had been noted in their abundance. As many as 556 respondents provided information concerning fungal ecology. In these descriptions, 35 taxa were mentioned by at least 5 respondents. Results: The data collected during interviews allowed us to create collective folk descriptions of habitat preferences and a list of 98 different macro-, meso-, and microhabitats of macrofungi described by the respondents. This list of recurring habitats assigned to particular macrofungal taxa coincides with, and sometimes exceeds, data available in scientific publications. Some habitat preferences observed by the informants have not yet been researched or tested by science. Out of 695 respondents, 366 (53%) noticed a steady decrease in local macrofungi abundance, and only one person claimed to have observed a steady increase. Imleria badia was the only species with increased abundance, as noted by fifteen independent respondents. The main listed reason for abundance decrease was drought (f = 186). Conclusions: Collected information on the ecology of fungi shows that local knowledge does not generally diverge from scientific knowledge. The acquired information related to macrofungal abundance and ecology may also be used as a tool for the formulation of new scientific questions and theories. The analysis of local fungi observations might contribute to broadening knowledge about local changes in fungi and enable new estimations related to large-scale analysis of macrofungal abundance.
... Degradation of soil physical properties caused by the passage of machinery has been extensively reported in various crop systems worldwide, especially as regards increased bulk density (Ampoorter et al., 2010) and decreases in pore volume, hydraulic conductivity and air permeability (Hartmann et al., 2014). Researchers have also demonstrated the negative impacts of clear-cutting on nutrient and carbon cycles (Christophel et al., 2015;Mayer et al., 2020;Siebers et al., 2018) and on faunal and microbial communities (Bottinelli et al., 2014;Frey et al., 2009;Hasegawa et al., 2014) in planted forests in various pedoclimatic conditions. Soil texture may significantly affect the way soil functions respond to disturbance. ...
Article
Soil health is defined as the soil's capacity to deliver ecosystem functions within environmental constraints. On tree plantations, clear-cutting and land preparation between two crop cycles cause severe physical disturbance to the soil and seriously deplete soil organic carbon and biodiversity. Rubber, one of the main tropical perennial crops worldwide, has a plantation life cycle of 25 to 40 years, with successive replanting cycles on the same plot. The aim of this study was to assess the effects of clear-cutting disturbance on three soil functions (carbon transformation, nutrient cycling and structure maintenance) and their restoration after the planting of the new rubber crop, in two contrasting soil situations (Arenosol and Ferralsol) in Côte d'Ivoire. In this 18-month diachronic study, we intensively measured soil functions under different scenarios as regards the management of logging residues and the use or not of a legume cover crop. We investigated the relationship between soil macrofauna diversity and soil heath. At both sites, clear-cutting and land preparation disturbed carbon transformation and nutrient cycling significantly and, to a lesser extent, structure maintenance function. When logging residues were applied, carbon transformation and structure maintenance functions were fully restored within 12 to 18 months after disturbance. By contrast, no restoration of nutrient cycling was observed over the study period. A legume cover crop mainly improved the restoration of carbon transformation. We found a strong relationship (P ≤ 0.001; R² = 0.62–0.66) between soil macrofauna diversity and soil health. Our overall results were very similar at the two sites, despite their contrasting soil conditions. Keeping logging residues in the plots and sowing a legume in the inter-row at replanting accelerated the restoration of soil functions after major disturbance caused by clear-cutting and land preparation. Our results confirm the necessity of taking soil macrofauna diversity into account in the management of tropical perennial crops.
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In the boreal region, peatland forests are a significant resource of timber. Under pressure from a growing bioeconomy and climate change, timber harvesting is increasingly occurring over unfrozen soils. This is likely to cause disturbance in the soil biogeochemistry. We studied the impact of machinery-induced soil disturbance on the vegetation, microbes, and soil biogeochemistry of drained boreal peatland forests caused by machinery traffic during thinning operations. To assess potential recovery, we sampled six sites that ranged in time since thinning from a few months to 15 years. Soil disturbance directly decreased moss biomass and led to an increase in sedge cover and a decrease in root production. Moreover, soil CO2 production potential, and soil CO2 and CH4 concentrations were greater in recently disturbed areas than in the control areas. In contrast, CO2 and CH4 emissions, microbial biomass and structure, and the decomposition rate of cellulose appeared to be uncoupled and did not show signs of impact. While the impacted properties varied in their rate of recovery, they all fully recovered within 15 years covered by our chronosequence study. Conclusively, drained boreal peatlands appeared to have high biological resilience to soil disturbance caused by forest machinery during thinning operations.
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forest sites on the PMB communities that were pro- filed using high-throughput sequencing. We observed differentiated responses of pqqC- and phoD-harbouring PMB communities to various soil conditions. There was significant variation among the sites in the diversity and structure of the phoD-harbouring community, which correlated with variation in phosphorus levels and non-capillary porosity; soil organic carbon and soil water content also affected the structure of the phoD-harbouring community. However, no significant difference in the diversity of pqqC-harbouring community was observed among different sites, while the structure of the pqqC-harbouring bacteria community was affected by soil organic carbon and soil total nitrogen, but not soil phosphorus levels. Overall, changes in soil conditions affected the phoD-harbouring community more than the pqqC-harbouring community. These findings provide a new insight to explore the effects of soil conditions on microbial communities that solubilize inorganic phosphate and mineralize organic phosphate.
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Temperate forest soils are an important sink for methane (CH4); however, disturbance through forest management and the creation of skid trails may significantly decrease soil’s ability to uptake CH4 or in some cases cause CH4 emissions. Skid trails might also be expected to show reductions in carbon dioxide (CO2) flux due to anaerobic conditions and reduced root activity. Studies to date have investigated skid trail greenhouse gas flux dynamics on experimentally created skid trails, which may not experience the full extent of traffic intensity or contain the various microsites found in actual harvested areas. We investigated variation of CH4 and CO2 fluxes based on traffic intensity, trail topography, and trail microsites in selection-managed hardwood forests in the Haliburton Highlands of Ontario, Canada. Skid trail soils showed reduced CH4 uptake, and primary and secondary trails were found to commonly be a CH4 source, especially on lower slope locations and on wheel track and trail middle ridge microsites. Skid trails also showed high CO2 emissions in the same areas. CH4 emissions on skid trails were correlated with low surface soil porosities and high soil moisture contents, which were found to occur most frequently on highly impacted trails, in low-lying areas, and in the wheel tracks and trail middle ridges. Scaling up, skid trails offset ~ 45% of CH4 uptake in untrafficked soils, an effect that should be accounted for in future greenhouse gas budgets of managed forests.
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Presented reasearch aimed to develop and analyse the suitability of the CART models for prediction of the extent and probability of occurrence of damage to outer soil layers caused by timber harvesting performed under varied conditions. Having employed these models, the author identified certain methods of logging works and conditions, under which they should be performed to minimise the risk of damaging forest soils. The analyses presented in this work covered the condition of soils upon completion of logging works, which was investigated in 48 stands located in central and south-eastern Poland. In the stands selected for these studies a few felling treatments were carried out, including early thinning, late thinning and final felling. Logging works were performed with use of the most popular technologies in Poland. Trees were cut down with chainsaws and timber was extracted by means of various skidding methods: with horses, semi-suspended skidding with the use of cable yarding systems, farm tractors equipped with cable winches or tractors of a skidder type, and forwarding employing farm tractors with trailers loaded mechanically by cranes or manually. The analyses also included mechanised forest operation with the use of a harvester and a forwarder. The information about the extent of damage to soil, in a form of wheel-ruts and furrows, gathered in the course of soil condition inventory served for construction of regression tree models using the CART method (Classification and Regression Trees), based on which the area, depth and the volume of soil damage under analysis, wheel-ruts and furrows, were determined, and the total degree of all soil disturbances was assessed. The CART classification trees were used for modelling the probability of occurrence of wheel-ruts and furrows, or any other type of soil damage. Qualitative independent variables assumed by the author for developing the models included several characteristics describing the conditions under which the logging works were performed, mensuration data of the stands and the treatments conducted there. These characteristics covered in particular: the season of the year when logging works were performed, the system of timber harvesting employed, the manner of timber skidding, the means engaged in the process of timber harvesting and skidding, habitat type, crown closure, and cutting category. Moreover, the author took into consideration an impact of the quantitative independent variables on the extent and probability of occurrence of soil disturbance. These variables included the following: the measuring row number specifying a distance between the particular soil damage and communication tracks, the age of a stand, the soil moisture content, the intensity of a particular cutting treatment expressed by units of harvested timber volume per one hectare of the stand, and the mean angle of terrain inclination. The CART models developed in these studies not only allowed the author to identify the conditions, under which the soil damage of a given degree is most likely to emerge, or determine the probability of its occurrence, but also, thanks to a graphical presentation of the nature and strength of relationships between the variables employed in the model construction, they facilitated a recognition of rules and relationships between these variables and the area, depth, volume and probability of occurrence of forest soil damage of a particular type. Moreover, the CART trees served for developing the so-called decision-making rules, which are especially useful in organising logging works. These rules allow the organisers of timber harvest to plan the management-related actions and operations with the use of available technical means and under conditions enabling their execution in such manner as to minimise the harm to forest soils. Furthermore, employing the CART trees for modelling soil disturbance made it possible to evaluate particular independent variables in terms of their impact on the values of dependent variables describing the recorded disturbance to outer soil layers. Thanks to this the author was able to identify, amongst the variables used in modelling the properties of soil damage, these particular ones that had the greatest impact on values of these properties, and determine the strength of this impact. Detailed results depended on the form of soil disturbance and the particular characteristics subject to analysis, however the variables with the strongest influence on the extent and probability of occurrence of soil damage, under the conditions encountered in the investigated stands, enclosed the following: the season of the year when logging works were performed, the volume-based cutting intensity of the felling treatments conducted, technical means used for completion of logging works, the soil moisture content during timber harvest, the manner of timber skidding, dragged, semi-suspended or forwarding, and finally a distance between the soil damage and transportation ducts. The CART models proved to be very useful in designing timber harvesting technologies that could minimise the risk of forest soil damage in terms of both, the extent of factual disturbance and the probability of its occurrence. Another valuable advantage of this kind of modelling is an opportunity to evaluate an impact of particular variables on the extent and probability of occurrence of damage to outer soil layers. This allows the investigator to identify, amongst all of the variables describing timber harvesting processes, those crucial ones, from which any optimisation process should start, in order to minimise the negative impact of forest management practices on soil condition.
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The increase of waterlogged environments is of recent concern due to changes in precipitation regimes and the frequent occurrence of extreme rainfall events. Therefore, it is necessary to comprehend the effects and responses of waterlogging for a better understanding of forests and urban afforestation under changing environments. We investigated root responses of five Japanese afforestation species (Pinus thunbergii, Acer mono, Quercus serrata, Alnus hirsuta and Fraxinus mandshurica) to waterlogging. Potted seedlings grown under natural conditions were waterlogged at soil-surface level for 2.5 months during the growing season. The in-growth core method was used to distinctively measure root growth. As a result, fine root growth during the waterlogging period was significantly decreased for P. thunbergii, A. mono and Q. serrata. Furthermore, root tissue density (RTD) of pre-existing roots was decreased, which suggests root damage such as partial root death and root decay. On the other hand, for A. hirsuta and F. mandshurica, fine root growth was not decreased under waterlogging. For A. hirsuta, although fine root growth continued at the top half, it was decreased at the bottom half. Root damage such as a decrease in RTD was observed for pre-existing roots. For F. mandshurica, root growth continued at the top and bottom half, and root damage of pre-existing roots was not observed at either the top or the bottom. From our results, it was suggested that P. thunbergii was most sensitive, followed by A. mono and Q. serrata. A. hirsuta and F. mandshurica were relatively tolerant; however, the most tolerant was F. mandshurica, as pre-existing roots were not damaged by waterlogging. Overall, root responses could be grouped into three groups: (1) P. thunbergii, A. mono, Q. serrata; (2) A. hirsuta; (3) F. mandshurica. The observed responses may reflect the species’ natural distributions.
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In recent years, the study of skid trail recovery processes has gained momentum. In this review, 121 studies on various aspects of skid trail recovery were evaluated to determine when, where and how the dominant factors that influence the process of recuperation occur. These studies were located proportionally in the following forest biomes: temperate (60%), tropical (31%), and boreal (9%). Research focused mainly on soil physical properties to ascertain if there had been evidence of recovery. The majority of studies of a decade or less after abandonment demonstrated that heavily used skid trails had not recovered. On the contrary, lightly used skid trails did present full recoveries over the same time span. Soil recovery tended to occur in medium- to coarse-textured soils in temperate and boreal forests. Considering all forest biomes, the impacts of compaction persisted at least two to five decades after logging operations. The impacts were evident in diminished tree heights and volumes from trees growing on skid trails. The last 50 years of research indicates that skid trails, globally, do recover from compaction, albeit slowly. Available from: https://cdnsciencepub.com/doi/abs/10.1139/cjfr-2020-0419
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Biochar may offer a substantial potential as a climate change mitigation and soil improvement agent; however, little is known about its effects in fertile soils subjected to standard agricultural practices. The aim of this short-term (60 days) lab experiment, under controlled temperature and soil moisture regimes, was to investigate the interaction between soil compaction and fertiliser and biochar addition in relatively fertile Luvisol. Three different biochar types and two soil compaction levels were investigated to describe their interactive effect on soil greenhouse gas emission (GHG). A very strong effect of soil compaction on N2O emission (+280%) and an interaction with biochar were found. The cumulative N2O emissions from the compacted soil were higher (from +70 to +371%, depending on the biochar type) than the uncompacted soil. Soil compaction resulted in a faster onset and a faster decrease of N2O production. Biochar did not affect the temporal dynamics of N2O evolution from either soil. The addition of digestate/crop biomass biochar has resulted in a significant increase in CO2 evolution both in compacted and uncompacted soils, compared to softwood from spruce (mixture of branches and wood chips) and wood pallets from softwood (spruce without bark) biochar. In the compacted soil, NH4 + availability was positively related to N2O efflux, and CO2 emission was positively correlated to both NH4 + and SOC content. An increase in GHGs as a result of an increase in NH4+ availability was seen both in compacted and uncompacted soils, while the rates of N2O emission were modified by biochar type. Our results show a strong interaction between biochar and soil conditions and a strong effect of biochar type on GHG emissions from agricultural soils.
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The impact of forest management operations on soil physical properties is important to understand, since management can significantly change site productivity by altering root growth potential, water infiltration and soil erosion, and water and nutrient availability. We studied soil bulk density and strength changes as indicators of soil compaction before harvesting and 1 and 5 years after harvest and site treatment on 12 of the North American Long-Term Soil Productivity sites. Severe soil compaction treatments approached root-limiting bulk densities for each soil texture, while moderate compaction levels were between severe and preharvest values. Immediately after harvesting, soil bulk density on the severely compacted plots ranged from 1% less than to 58% higher than preharvest levels across all sites. Soil compaction increases were noticeable to a depth of 30 cm. After 5 years, bulk density recovery on coarse-textured soils was evident in the surface (0-10 cm) soil, but recovery was less in the subsoil (10-30 cm depth); fine-textured soils exhibited little recovery. When measured as a percentage, initial bulk density increases were greater on fine-textured soils than on coarser-textured soils and were mainly due to higher initial bulk density values in coarse-textured soils. Development of soil monitoring methods applicable to all soil types may not be appropriate, and more site-specific techniques may be needed for soil monitoring after disturbance.
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To investigate the potential role of microbial community composition in soil carbon and nitrogen cycling, we transplanted soil cores between a grassland and a conifer ecosystem in the Sierra Nevada California and measured soil process rates (N-mineralization, nitrous oxide and carbondioxide flux, nitrification potential), soil water and temperature, and microbial community parameters (PLFA and substrate utilization profiles) over a 2 year period. Our goal was to assess whether microbial community composition could be related to soil process rates independent of soil temperature and water content. We performed multiple regression analyses using microbial community parameters and soil water and temperature as X-variables and soil process rates and inorganic N concentrations as Y-variables. We found that field soil temperature had the strongest relationship with CO2 production and soil NH4 + concentration, while microbial community characteristics correlated with N2O production, nitrification potential, gross N-mineralization, and soil NO3 − concentration, independent of environmentalcontrollers. We observed a relationship between specific components of the microbial community (as determined by PLFA) and soil processes,particularly processes tightly linked to microbial phylogeny (e.g. nitrification). The most apparent change in microbial community composition in response to the 2 year transplant was a change in relative abundance of fungi (there was only one significant change in PLFA biomarkers for bacteria during 2 years). The relationship between microbial community composition and soil processes suggests that prediction of ecosystem response to environmental change may be improved by recognizing and accounting for changes in microbial community composition and physiological ecology.
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The USDA Forest Service initiated a national study in the early 1990s to examine the effects of organic matter removal, compaction, and vegetation control on tree growth and soil processes at several locations across the United States and Canada. Our study was undertaken on the Lower Coastal Plain of North Carolina installation during the second and the fifth growing seasons following loblolly pine (Pinus taeda L.) plantation establishment. We used the in situ soil core incubation method to assess net N mineralization, and collections were conducted monthly from March to December in 1993 and 1996. The largest differences in N mineralization resulted from soil type differences between blocks. Organic matter removal did not affect N mineralization in either year; however, compaction reduced N mineralization during both years. Vegetation control had a pronounced positive effect on N mineralization and was only slightly less important as compared with soil type. Mineralization rates in year 5 were 80% less than in year 2. We hypothesized that the high N mineralization rates in year 2 may be related to a decrease in the input of soluble organic C following harvest (reducing immobilization), a quick mineralization of microbial N, fluctuating soil temperature and water conditions, and fine roots and litter biomass input following harvest.
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We (i) quantified effects of skidder yarding on soil properties and seedling growth in a portion of western Oregon, (ii) determined if tilling skid trails improved tree growth, and (iii) compared results with those from an earlier investigation in coastal Washington. Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were hand planted at eight recent clearcuts in skid ruts in either nontilled or tilled trails, in adjacent soil berms, and in adjacent logged-only portions. Four and 5 years after skidding, rut depths averaged 15 cm below the original soil surface; mean fine-soil bulk density (0-30 cm depth) below ruts of nontilled trails exceeded that on logged-only portions by 14%. Height growth on nontilled trails averaged 24% less than on logged-only portions in year 4 after planting and decreased to 6% less in year 7. For years 8-10, mean height growth was similar for all treatments. Reduced height growth lasted for about 7 years compared with 2 years for coastal Washington. Ten years after planting, trees in skid-trail ruts averaged 10% shorter with 29% less volume than those on logged-only portions. Tillage improved height and volume growth to equal that on logged-only portions. Generalizations about negative effects of skid trails on tree growth have limited geographic scope.
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This revised and updated edition focuses on constrained ordination (RDA, CCA), variation partitioning and the use of permutation tests of statistical hypotheses about multivariate data. Both classification and modern regression methods (GLM, GAM, loess) are reviewed and species functional traits and spatial structures analysed. Nine case studies of varying difficulty help to illustrate the suggested analytical methods, using the latest version of Canoco 5. All studies utilise descriptive and manipulative approaches, and are supported by data sets and project files available from the book website: Http://regent.prf.jcu.cz/maed2/. Written primarily for community ecologists needing to analyse data resulting from field observations and experiments, this book is a valuable resource to students and researchers dealing with both simple and complex ecological problems, such as the variation of biotic communities with environmental conditions or their response to experimental manipulation.
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We have studied the inhibiting effect offertilisation and soil compaction on CH4oxidation by measuring gas fluxes and soil mineral Ndynamics in the field, and CH4 oxidation rates inlaboratory-incubated soil samples. The fertilisationand soil compaction field experiment was establishedin 1985, and the gas fluxes were measured from 1992 to1994. Methane oxidation was consistently lower infertilised than in unfertilised soil, but thereapparently was no effect of repeated fertiliseradditions on the fertilised plots. The measuredmineral N in fertilised and unfertilised soil showedlarge differences in NH4 + concentrationsjust after fertilisation, but the levels rapidlyconverged because of plant uptake and nitrification.The CH4 oxidation rate did not reflect thesecontrasting mineral N patterns, suggesting that theCH4 oxidation capacity remaining in the soil thathad been fertilised since 1985 was largely insensitiveto ammonia in the new fertiliser. Thus, competitiveinhibition by ammonia may have been involved in theearly stage of the field fertiliser experiment, butthe CH4 oxidation remaining after 7 to 9 years ofcontinued fertilisation seems not to have beenaffected by ammonia. The substrate affinity of theCH4-oxidizing microflora appeared to be the samein both the fertilised soil and the unfertilisedcontrol, as judged from the response to elevatedCH4 concentrations (52 l l–1) inlaboratory incubations. Soil compaction resulted in apersistent reduction of CH4 influx, also seen inlaboratory incubations with sieved (4-mm mesh) soilsamples. Since the sieving presumably removesdiffusion barriers created by the soil compaction, thefact that compaction effects persisted through thesieving may indicate that soil compaction has affectedthe biological potential for CH4 oxidation in thesoil.
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The state of compactness is an important soil structure and quality attribute, and there is a need to find a parameter for its characterization that gives directly comparable values for all soils. The use of some relative bulk density value for this purpose, particularly the degree of compactness (Håkansson, 1990), is discussed in this review. The degree of compactness has been defined as the dry bulk density of a soil as a percent of a reference bulk density obtained by a standardized uniaxial compression test on large samples at a stress of 200 kPa. The bulk density should be determined at standardized moisture conditions, to prevent problems caused by water content variations in swelling/shrinking soils. The degree of compactness (D) makes results of soil compaction experiments more generally applicable. Whereas the bulk density or porosity optimal for crop growth vary greatly between soils, the optimal D-value is virtually independent of soil composition. Critical limits of penetration resistance (3 MPa) and air-filled porosity (10%, v/v) are similarly related to the D-value and matric water tension in most soils. As the D-value increases above the optimal, the tension range offering non-limiting conditions becomes increasingly limited. The D-value of the plough layer induced by a given number of passes by a certain vehicle is similar in all soils, provided the moisture conditions are comparable. The degree of compactness facilitates modelling of soil and crop responses to machinery traffic. Although this parameter was primarily introduced for use in annually disturbed soil layers, its use may be extended to undisturbed soil layers.
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The effects of fumigation on organic C extractable by 0.5 M K2SO4 were examined in a contrasting range of soils. EC (the difference between organic C extracted by 0.5 M K2SO4 from fumigated and non-fumigated soil) was about 70% of FC (the flush of CO2-C caused by fumigation during a 10 day incubation), meaned for ten soils. There was a close relationship between microbial biomass C, measured by fumigation-incubation (from the relationship Biomass C = FC/0.45) and EC given by the equation: Biomass C = (2.64 ± 0.060) EC that accounted for 99.2% of the variance in the data. This relationship held over a wide range of soil pH (3.9–8.0).ATP and microbial biomass N concentrations were measured in four of the soils. The ratios were very similar in the four soils, suggesting that both ATP and the organic C rendered decomposable by CHCl3 came from the soil microbial biomass. The C:N ratio of the biomass in a strongly acid (pH 4.2) soil was greater (9.4) than in the three less-acid soils (mean C:N ratio 5.1).We propose that the organic C rendered extractable to 0.5 m K2SO4 after a 24 h CHCl3-fumigation (EC) comes from the cells of the microbial biomass and can be used to estimate soil microbial biomass C in both neutral and acid soils.
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Soil compaction and organic matter removal are two common disturbances caused by forest management practices, such as harvesting and site preparation. In this study, we investigated the effects of severe soil compaction and whole tree harvesting plus forest floor removal (referred to as forest floor removal below, as compared with stem-only harvesting) on soil microbial biomass C (MBC) and N (MBN) and net N mineralization and nitrification rates in the forest floor and 0–10cm mineral soil between July 2002 and 2003 in a boreal forest long-term soil productivity (LTSP) site near Dawson Creek, BC, Canada. Soil compaction increased mineral soil bulk density by an average of 24%, reduced aeration porosity by as much as 50%, and lowered growing season soil temperature and moisture content. There was no interaction between soil compaction and forest floor removal on soil microbial properties and N transformation processes. Soil compaction reduced net nitrification rates in both the forest floor and mineral soil and reduced MBN in the mineral soil at several sampling dates and reduced available N content in both the forest floor and mineral soil in the July 2002 sampling. Forest floor removal tended to decrease MBC and MBN, most likely attributable to the reduced substrate availability for microbial metabolism, but tended to increase net N mineralization and nitrification rates, possibly as a result of elevated soil temperature. While short-term negative effects of soil compaction on MBN and available N were found, no negative impact of forest floor removal on N transformation rates was obvious. This LTSP experiment will continue to monitor the long-term effects of both soil compaction and organic matter removal on N cycling processes and stand productivity.
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a 10-m radius of action to both sides of the skid trail. This means that skid trails make up approximately 12 Fluxes of the greenhouse gases, N2O and CH4, were measured to 16% of the total operational area. In Germany a across a skid trail at three beech (Fagus sylvatica L.) forest sites with soils of different texture. At each site three skid trails were established permanent skid trail system with a skid trial distance of by applying two passes with a forwarder. Soil compaction in the middle 20 m is recommended by the Forestry Commissions of the wheel track caused a considerable increase of N2O emissions (Anonymous, 1991) to ensure efficient wood harvesting with values elevated by up to 40 times the uncompacted ones. Compac- but also to avoid the risk of unrestricted soil trafficking tion reduced the CH4 consumption at all sites by up to 90%, and at during harvesting. the silty clay loam site its effect was such that CH4 was even released. Soil compaction by harvesting machines alters many These changes in N2O and CH4 fluxes were caused by a reduction in important soil properties, such as bulk density, aeration macropore volume and an increase of the water-filled pore space porosity (McNabb et al., 2001), hydraulic conductivity (WFPS). Additionally, the slipping of the forwarder's wheels led to