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-Sketch of location of the sampling points within gap and adjacent closed canopy. Capital letters indicate cardinal points.
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Understanding the effects of silvicultural practices including single-tree selection on soil properties is essential for forest management in temperate broadleaved beech forests. Changes in physico-chemical and biological soil properties in 15 harvest-created gaps under single-tree selection and the adjacent closed canopies, with five replications...
Contexts in source publication
Context 1
... 15 artificial gaps were sampled and categorized in three size classes of five replicates each: small (85-130 m 2 ), medium (131-175 m 2 ) and large (176-300 m 2 ). The gap area was measured using the formula for an ellipse: A = (πLW) / 4, where L is the longest distance within the gap (m), and W is the largest distance perpendicular to L (m - Fig. 1). These distances were measured between stems of the trees at the border. All gaps were oriented in north exposition within forest (Fig. ...
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... 2 ) and large (176-300 m 2 ). The gap area was measured using the formula for an ellipse: A = (πLW) / 4, where L is the longest distance within the gap (m), and W is the largest distance perpendicular to L (m - Fig. 1). These distances were measured between stems of the trees at the border. All gaps were oriented in north exposition within forest (Fig. ...
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... samples were taken in October 2017, six years after gap creation. After removal of the litter layer, soil samples were collected by hand soil corer (8 cm diameter) from the shallower rooted soil layer up to 20 cm depth. The sampling protocol followed the scheme reported in Fig. 1. For each gap, 4 soil samples were collected at the cardinal points of the gap border and 4 at the adjacent closed canopy at a distance of 20 m from the gap (Fig. 1). The four gapedge-cores were mixed to produce one composite sample (hereafter named gapedge-core); the same was done for closed canopy cores (hereafter named ...
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... layer, soil samples were collected by hand soil corer (8 cm diameter) from the shallower rooted soil layer up to 20 cm depth. The sampling protocol followed the scheme reported in Fig. 1. For each gap, 4 soil samples were collected at the cardinal points of the gap border and 4 at the adjacent closed canopy at a distance of 20 m from the gap (Fig. 1). The four gapedge-cores were mixed to produce one composite sample (hereafter named gapedge-core); the same was done for closed canopy cores (hereafter named closecanopy-core). One more core was collected at the center of the gap (hereafter named gap-center-core), so that soil samples totaled three per gap. Each composite soil sample ...
Context 5
... 15 artificial gaps were sampled and categorized in three size classes of five replicates each: small (85-130 m 2 ), medium (131-175 m 2 ) and large (176-300 m 2 ). The gap area was measured using the formula for an ellipse: A = (πLW) / 4, where L is the longest distance within the gap (m), and W is the largest distance perpendicular to L (m - Fig. 1). These distances were measured between stems of the trees at the border. All gaps were oriented in north exposition within forest (Fig. ...
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... 2 ) and large (176-300 m 2 ). The gap area was measured using the formula for an ellipse: A = (πLW) / 4, where L is the longest distance within the gap (m), and W is the largest distance perpendicular to L (m - Fig. 1). These distances were measured between stems of the trees at the border. All gaps were oriented in north exposition within forest (Fig. ...
Context 7
... samples were taken in October 2017, six years after gap creation. After removal of the litter layer, soil samples were collected by hand soil corer (8 cm diameter) from the shallower rooted soil layer up to 20 cm depth. The sampling protocol followed the scheme reported in Fig. 1. For each gap, 4 soil samples were collected at the cardinal points of the gap border and 4 at the adjacent closed canopy at a distance of 20 m from the gap (Fig. 1). The four gapedge-cores were mixed to produce one composite sample (hereafter named gapedge-core); the same was done for closed canopy cores (hereafter named ...
Context 8
... layer, soil samples were collected by hand soil corer (8 cm diameter) from the shallower rooted soil layer up to 20 cm depth. The sampling protocol followed the scheme reported in Fig. 1. For each gap, 4 soil samples were collected at the cardinal points of the gap border and 4 at the adjacent closed canopy at a distance of 20 m from the gap (Fig. 1). The four gapedge-cores were mixed to produce one composite sample (hereafter named gapedge-core); the same was done for closed canopy cores (hereafter named closecanopy-core). One more core was collected at the center of the gap (hereafter named gap-center-core), so that soil samples totaled three per gap. Each composite soil sample ...
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Despite the crucial role of fine roots for water and nutrient uptake, soil biological activity and ecosystem carbon cycling, the response of root dynamics to rapidly advancing land-use change in the tropics is still poorly understood. To address this uncertainty, we investigated the consequences of tropical forest conversion to intensively managed...
Research Highlights: Fine roots play an important role in plant growth as well as in carbon (C) and nutrient cycling in terrestrial ecosystems. Gaining a wider knowledge of their dynamics under forest gap opening would improve our understanding of soil carbon input and below-ground carbon stock accumulation. Single-tree selection is increasingly re...
Citations
... Effectively mitigating climate change may be achieved through the enhancement of forest carbon stocks resulting from sustainable forest management (Huang et al. 2023). Nevertheless, our results underscored a consistent reduction in both C org and C mic following gap creation, indicating a potential decline in the soil carbon stock (Ni et al. 2016;Amolikondori et al. 2020). In general, heightened levels of irradiance and soil temperature resulting from gap creation or forest thinning accelerated soil microbial activity, leading to increased soil respiration and, consequently, enhanced mineralization of soil organic matter and elevated surface carbon efflux (Scharenbroch and Bockheim 2008) (Fig. 9). ...
Key message
The forest canopy gaps, formed by natural or anthropogenic factors, have been found to reduce soil carbon content and increase nutrient availability. The magnitudes of these effects have been observed to increase with gap age and size, and are largely influenced by changes in temperature, precipitation, and solar radiation.
Context
Local studies have illustrated the influence of canopy gaps on the spatial heterogeneity of soil carbon and nutrients, playing a pivotal role in driving forest regeneration and succession. Nevertheless, it remains largely unknown whether the response of soil carbon and nutrient content to gap formation is consistent across forest ecosystems at global scale.
Aims
The aim of this paper is to assess the homogeneity of the observed responses of soil carbon and nutrients following gap formation among a wide array of forest ecosystems and climatic regions.
Methods
We performed a meta-analysis synthesizing 2127 pairwise observations from 52 published articles to quantify the changes in in soil physical, chemical, and microbial variables resulting from gap creation in natural forests and plantations spanning tropical to boreal regions.
Results
Canopy gaps resulted in significant decrease of soil organic carbon ( C org ) and microbial carbon ( C mic ). The concentrations of ammonium (NH 4 ⁺ ), nitrate (NO 3 ⁻ ), and available phosphorus (available P) increased following gap creation. These changes mainly occurred in the growing season and in the mineral soil layer, becoming more pronounced with increasing gap age and size. The change in C org was negatively regulated by mean annual precipitation, and was associated with the changes in N t and N mic . The change in NH 4 ⁺ was positively regulated by mean annual temperature, and was associated with the changes in available P and oxidoreductases (Ox-EEAs). The model explaining the change in soil carbon content exhibited a higher explanatory power than the one accounting for changes in soil nutrient availability.
Conclusion
The results indicated that forest canopy gaps resulted in a reduction in soil carbon content and an increase in nutrient availability. These findings contribute to a better understanding of the role of small-scale disturbances as drivers of forest ecosystem succession.
... Strongly acid soils dominate the study area with an area share of 45% (Figure 4b). The soil pH range in our study is consistent with those reported in other studies [62][63][64][65]. The EC was between 0.1 mS/cm and 6.48 mS/cm, with an average of 0.9 mS/cm. ...
The dominant height of forest stands (SDH) is an essential indicator of site productivity in operational forest management. It refers to the capacity of a particular site to support stand growth. Sites with taller dominant trees are typically more productive and may be more suitable for certain management practices. The present study investigated the relationship between the dominant height of oriental beech stands and numerous environmental variables, including physiographic, climatic, and edaphic attributes. We developed models and generated maps of SDH using multilinear regression (MLR) and regression tree (RT) techniques based on environmental variables. With this aim, the total height, diameter at breast height, and age of sample trees were measured on 222 sample plots. Additionally, topsoil samples (0–20 cm) were collected from each plot to analyze the physical and chemical soil properties. The statistical results showed that latitude, elevation, mean annual maximum temperature, and several soil attributes (i.e., bulk density, field capacity, organic carbon, and pH) were significantly correlated with the SDH. The RT model outperformed the MLR model, explaining 57% of the variation in the SDH with an RMSE of 2.37 m. The maps generated by both models clearly indicated an increasing trend in the SDH from north to south, suggesting that elevation above sea level is a driving factor shaping forest canopy height. The assessments, models, and maps provided by this study can be used by forest planners and land managers, as there is no reliable data on site productivity in the studied region.
Keywords: stand productivity; site factors; multiple linear regression; regression tree; modeling
... Compared to the climatic factors in forest opening areas, lower wind speed and less direct solar radiation lead to temperature and moisture variations that are dampened under or within tree canopies [15]. These alterations influence the specific environments controlling the interactions between plants and soil organisms [9], and thereby alter the functional communities of soil invertebrates and microbes, litter chemistry and soil nutrient availability to a considerable extent [11,16]. As a result, gap formation has the potential to not only directly affect the degree and rate of litter humification at a relatively small spatial scale by modulating the climatic conditions [3,17], but also indirectly alter the humification process by modifying the litter quality, decomposing organisms and soil nutrient availability [9,[18][19][20]. ...
Litter humification plays a crucial role in organic matter formation and soil carbon sequestration in forest ecosystems. However, how forest gap formation and gap size variation affect the litter humification process remains poorly understood. An eight-year in situ decomposition experiment was conducted to evaluate humus accumulation (humic substances, humic and fulvic acid), humification degrees, humification ratios and optical properties (ΔlogK, E4/E6 and A600/C) of Minjiang fir (Abies faxoniana Rehder & E.H.Wilson) twig litter in four gap size treatments in an alpine primitive forest on the eastern Tibetan Plateau, including (1) closed canopies, (2) small gaps (38–46 m2 in size), (3) medium gaps (153–176 m2 in size),and (4) large gaps (255–290 m2 in size). The results indicated that the accumulation of humic substances and humic acid in the closed canopies was significantly higher than that in the large gaps during the first two years of decomposition. After eight years of decomposition, there were significant differences in the humic substance accumulations and the values of ΔlogK and A600/C among the different gap sizes. Furthermore, twig litter was humified in the first 2 years of incubation, and the net accumulation of humic substances was ranged from −23.46% to −44.04% of the initial level at the end of the experiment. The newly accumulated humus was young (mature (type Rp) humus) and transformed to mature (type A) humus after 4–6 years of decomposition. Partial least squares (PLS) suggested that gap-induced variations in twig litter chemistry (i.e., contents of cellulose, lignin, nitrogen (N) and phosphorus (P), and the ratios of C/N N/P) mainly drove the process of twig litter humification. Our results presented here denote that the formation of forest gaps retard twig litter humification process, which might be detrimental to carbon sequestration in the alpine forest ecosystems.
... The disturbances have an effect on the size of forest gaps, and canopy opening and creation of gaps significantly affect regeneration in tropical forests (Coates and Burton 1997;Zhu et al. 2014;Sharma et al. 2019;Awasthi et al. 2020;Reis et al. 2021). Gap formation and their size are influenced by the agents of disturbance (e.g., windthrow, fire, storm, and natural dying) and vary from stand-to gap-scale (Runkle 1985;Oliver and Larson 1996;Nagel and Diaci 2006;Amolikondori et al. 2020). Younger forest stands usually have high frequency of gap formation while in mature stands the occurrence of gaps is low (Runkle 1985;Hart and Grissino-Mayer 2009). ...
Natural regeneration and forest successional development are influenced by gap formation in forest stands. Nonetheless, there are limited studies that provide quantitative information on the influence of gaps on forest regeneration. We evaluated characteristics of inner and outer canopy gaps and their effects on natural regeneration in 40 canopy gaps in Sitapahar forest reserve of Bangladesh. A total of 50 individuals of 27 gapmaker tree species were found, of which 58% were formed by logging and the rest by natural damages. Elliptical shape represented 53% of the gaps followed by circular and rectangular gaps. The mean area of the outer and inner gaps was 50.1 ± 8.6 and 20.0 ± 3.0 m2, respectively. Gap formation types and shapes did not vary significantly between outer and inner gaps, while the mean gap area in older gaps was significantly higher than in new gaps. In comparison with outer gaps, mean densities of seedlings and saplings in the inner gaps were significantly higher, which is probably because of the closeness to seed trees. The diversity index of regenerating species and their height and collar diameter did not vary significantly between the inner and outer gaps. Positive, but weak relationships of gap area with subcanopy tree density and diversity were found. Since gaps were found dominated by few light-demanding tree species such as Brownlowia elata, Lithocarpus acuminata, Lithocarpus polystachya, and Macaranga denticulate, it is suggested that larger gaps need to be replanted with a combination of light-demanding and shade-tolerant native trees.
... On the other hand, as expected, no difference was revealed between the two UND soil portions, considering that the silviculture treatment and the magnitude of intervention and canopy removal was the same for the two investigated forest subcompartments. Impact level in UND soil is indeed related to the degree of canopy cover removal [60,61]. ...
Considering that forests are crucial in the ecosystem of our planet and that forests provide timber products as well as several ecosystem services, it is evident that the application of sustainable forest operations (SFOs) is of substantial importance to achieve sustainable forest management (SFM). One of the most important issues to be evaluated when dealing with SFOs is limiting the disturbance and impacts related to logging. Harvesting activities can indeed alter the conditions of soil through compaction and litter removal which can also lead to modifications from the biological point of view, for example, diminishing the presence of soil microarthropods. While keeping these objectives in focus, the aim of the present study was to evaluate physico-chemical and biological impacts on forest soil in Mediterranean beech forests after forest logging with two different extraction systems, which are forestry-fitted farm tractors equipped with winch and forwarder. Specifically , authors aimed to investigate: i) soil disturbance levels of ground-based extraction methods; ii) soil disturbance levels of the applied forestry intervention; iii) soil disturbance levels between winching-skidding and forwarding. Findings showed that the physical, chemical, and biological soil features were slightly disturbed by the forestry itself. In addition, forest operations and machine traffic showed clear soil disturbance, resulting in a substantial alteration of the characteristics. Between the two extraction techniques tested, winching caused less disturbance while forwarding had stronger impacts. However, it should be noted that these impact levels are found only on approximately 28% of the surface where operations were carried out. From the evidence gathered in this study, winching seems a less impactful extraction method in the studied context. On the other hand, to decrease the impact of forwarding, some technical adjustments such as bogie-tracks, as well as improved operator training, should be applied.
... Tree canopy is the key regulator of solar radiation which prevents over 95% of light radiation from reaching the Earth's surface (Ishii, Azuma, and Nabeshima 2013). Plants under the tree canopy are benefited from increased organic matter, reduced daily oscillations of temperature, increased humidity, lower water vapor deficit and reduced transpiration (Garkoti 1992;Joshi et al. 2001;Garkoti, Zobel, and Singh 2003;Das et al. 2008;Sagar, Pandey, and Singh 2012;Valladares et al. 2016;Singh et al. 2017;Desta, Lisanenwork, and Muktar 2018;Kumar, Verma, and Garkoti 2020;Amolikondori et al., 2020). However, the negative effects of tree canopy also exist, such as reduced light availability for photosynthesis, tree root competition for water and soil nutrients, allelopathic effects of trees and increased phytophagous fungi and pests (Garkoti and Singh 1995;Valladares et al. 2016). ...
Herbaceous vegetation is of great ecological importance and responds quickly to environmental changes. The present study was aimed to understand the variation in herbaceous species composition, biomass and soil physico-chemical properties in the naturally formed gap and the understory of semi-arid forests in the Aravalli hills. Four permanent plots consisting of the gap as well as the understory were established. To study herbs phytosociological attributes and biomass, 10 quadrats of 0.5 X 0.5 m size were laid in each plot. For soil physico-chemical properties, 5 soil samples were collected randomly at 0–10 cm depth from each plot. Relationships among biodiversity indices, herbaceous biomass and soil physico-chemical properties were determined using Redundancy Analysis (RDA) and correlation analysis. Across the sites, Poaceae was the dominant family. All species showed a contagious distribution pattern. In the understory, Importance Value Index (IVI) was the recorded highest for Oplismenus burmannii, ranging from 138 to 230.5 while in the gap, it was the highest for Achyranthes aspera (56.15) followed by Eragrostis ciliaris (53.1). Both sites included, herbaceous community biomass in the gap ranging from 700 to 900 g m-2 while in the understory it ranged from 30 to 70 g m-2. Cenchrus ciliaris (597.97 g m-2) and Chrysopogon sp. (391.2 g m-2) contributed a major proportion of herbaceous community biomass in the gap. Oplismenus burmannii (52.2 g m-2), Dipteracanthus prostratus (16.6 g m-2) and Cynodon dactylon (9.6 g m-2) contributed a major proportion of herbaceous community biomass in the understory. The understory soil had significantly (p < 0.05) higher soil moisture (%), electrical conductivity (EC), soil organic carbon (SOC) and soil total nitrogen (TN) compared to the gap. Even though canopy had positive effects on soil physico-chemical properties, it has negatively influenced herbaceous species composition, diversity and biomass, due to significant reduction in solar radiation reaching the ground.
... Tree canopy is the key regulator of solar radiation which prevents over 95% of light radiation from reaching the Earth's surface (Ishii, Azuma, and Nabeshima 2013). Plants under the tree canopy are benefited from increased organic matter, reduced daily oscillations of temperature, increased humidity, lower water vapor deficit and reduced transpiration (Garkoti 1992;Joshi et al. 2001;Garkoti, Zobel, and Singh 2003;Das et al. 2008;Sagar, Pandey, and Singh 2012;Valladares et al. 2016;Singh et al. 2017;Desta, Lisanenwork, and Muktar 2018;Kumar, Verma, and Garkoti 2020;Amolikondori et al., 2020). However, the negative effects of tree canopy also exist, such as reduced light availability for photosynthesis, tree root competition for water and soil nutrients, allelopathic effects of trees and increased phytophagous fungi and pests (Garkoti and Singh 1995;Valladares et al. 2016). ...
Herbaceous vegetation is of great ecological importance and responds quickly to environmental changes. The present study was aimed to understand the variation in herbaceous species composition, biomass and soil physico-chemical properties in the naturally formed gap and the understory of semi-arid forests in the Aravalli hills. Four permanent plots consisting of the gap as well as the understory were established. To study herbs phytosociological attributes and biomass, 10 quadrats of 0.5 × 0.5 m size were laid in each plot. For soil physico-chemical properties, 5 soil samples were collected randomly at 0–10 cm depth from each plot. Relationships among biodiversity indices, herbaceous biomass and soil physico-chemical properties were determined using Redundancy Analysis (RDA) and correlation analysis. Across the sites, Poaceae was the dominant family. All species showed a contagious distribution pattern. In the understory, Importance Value Index (IVI) was the recorded highest for Oplismenus burmannii, ranging from 138 to 230.5 while in the gap, it was the highest for Achyranthes aspera (56.15) followed by Eragrostis ciliaris (53.1). Both sites included, herbaceous community biomass in the gap ranging from 700 to 900 g m⁻² while in the understory it ranged from 30 to 70 g m⁻². Cenchrus ciliaris (597.97 g m⁻²) and Chrysopogon sp. (391.2 g m⁻²) contributed a major proportion of herbaceous community biomass in the gap. Oplismenus burmannii (52.2 g m⁻²), Dipteracanthus prostratus (16.6 g m⁻²) and Cynodon dactylon (9.6 g m⁻²) contributed a major proportion of herbaceous community biomass in the understory. The understory soil had significantly (p < 0.05) higher soil moisture (%), electrical conductivity (EC), soil organic carbon (SOC) and soil total nitrogen (TN) compared to the gap. Even though canopy had positive effects on soil physico-chemical properties, it has negatively influenced herbaceous species composition, diversity and biomass, due to significant reduction in solar radiation reaching the ground.
... To study the effects of gap size on fine roots properties, a broadleaved Fagus orientalis L. forest, covering an area of 40.4 ha, was selected in the Caspian area (Mazandaran province), northern Iran (36 • 12 N,53 • 24 E). The general characteristics of this area were already described in a previous work carried out on the same site [45]. Briefly, the study site is located at an elevation of 1000-1200 m a.s.l., on a north-facing slope of 0-30%. ...
... Furthermore, regarding the spatial localization of the soil sampling points for edge trees, the adopted distances of 5 and 8 m from the trunk in the same short-term experiments [8,9] were higher than the 1 m used in the present work, which fell under the canopy crowns of rather tall trees (on average 31 m). In fact, previous findings on the soil characteristics (moisture content, bulk density, total N, P, and soil organic carbon) from the same experimental gaps [45] showed a lack of significant differences between edge and closed canopy trees. These findings also highlighted the low impacts of the adopted management practices on soil characteristics, which did not extend over the medium term [50,51]. ...
... Differently, a lack of consistency persists about the possible N concentration increase in fine roots in response to gap opening [30], particularly when consequent to artificial gap formation. Most of the studies had focused on alteration on soil processes such as nutrient release during litter decomposition [53,54], microbial activity [45,54], net mineralization and nitrification [55], but few papers concern fine roots [8,9,11]. Thinning operations stimulate the N concentration increase in European beech forests in the Southern Alps, [18], which results in fine roots with a shorter lifespan than those living in the forest left to grow for many years. ...
Research Highlights: Fine roots play an important role in plant growth as well as in carbon (C) and nutrient cycling in terrestrial ecosystems. Gaining a wider knowledge of their dynamics under forest gap opening would improve our understanding of soil carbon input and below-ground carbon stock accumulation. Single-tree selection is increasingly recognized as an alternative regime of selection cutting sustaining biodiversity and carbon stock, along with timber production, among ecosystem functions. However, the fine root response in terms of morphological and chemical composition to the resulting harvest-created gaps remains unclear. Background and Objectives: This paper investigates the effect in the medium term (i.e., 6 years after logging) of differently sized harvest-created gaps on fine root dynamics and chemical composition. Materials and Methods: A total of 15 differently sized gaps (86.05–350.7 m2) and the adjacent 20 m distant closed canopies (control) were selected in a temperate Fagus orientalis forest (Hyrcanian region, Iran). Eight soil cores were collected at the cardinal points of the gap edge, including four facing the gap area—the same at the adjacent intact forest. Results: For the selected edge trees, the different size of gaps, the core position, and the tree orientation did not affect the investigated morphological traits, except for the slightly higher specific root length (SRL) for the larger fine root fraction (1–2 mm) in the side facing the gap area. Differently, the investigated chemical traits such as N concentration and cellulose:lignin ratio significantly increased with increasing gap size, the opposite for C:N ratio and lignin. Moreover, N concentration and C:N significantly decreased and increased with the fine root diameter, respectively. Conclusions: This work highlighted that, in the medium term and within the adopted size range, artificial gap opening derived from single-tree selection practice affected the chemistry rather than the biomass and morphology of gap-facing fine roots of edge trees. The medium term of six years after gap creation might have been long enough for the recovery of the fine root standing biomass to the pre-harvest condition, particularly near the stem of edge trees. A clear size threshold did not come out; nevertheless, 300 m2 may be considered a possible cut-off determining a marked change in the responses of fine roots.
Vargas-Lomeln, J.G.; Macas-Rodrguez, M..; Zaraza-Villaseor, P.; Rodrguez-Zaragoza, F.A.; Neri-Luna, C., and Albuquerque, F., 2023. The effect of Prosopis juliflora (Fabaceae) on the physical and chemical properties of coastal dune soil in western Mexico. Journal of Coastal Research, 39(1), 6372. Charlotte (North Carolina), ISSN 0749-0208. Prosopis juliflora (Fabaceae) is a dominant legume and potential ecosystem engineer in the dunes of Jalisco, western Mexico. The objective of the present study was to evaluate how P. juliflora modifies soil physical and chemical properties in three coastal dunes that belong to different watersheds. To determine the physical properties of the three sites, soil samples were taken inside the canopy of five P. juliflora trees and five soil samples were taken outside their canopies. The same trees and soil positions regarding the canopy of P. juliflora were considered to determine the chemical properties, but the samples were taken at two different depths. A multidimensional and permutational analysis of variance (PERMANOVA) was performed to evaluate differences in the physical properties among the sites and between the sampling positions relative to the canopy of P. juliflora. This PERMANOVA also evaluated differences among sites, sample depths, and the positions of the samples relative to the P. juliflora canopy. A test of homogeneity of dispersions was performed to determine the data dispersion type, whereas a similarity percentage analysis identified which variables contributed most to the observed differences. A principal coordinate analysis was performed to visualize the differences in the model. The results demonstrated that P. juliflora modified the soil physical properties, specifically the real density, total porosity percentage, and percentages of silt and clay. The soil physical properties also varied significantly among the three sites. In addition, P. juliflora modified the soil chemical properties, increasing the electrical conductivity, pH, and total nitrogen, iron, and available phosphorus content. The results show significant differences between the two soil depths, as well as among sites. Ultimately, this study contributes to understanding of the implications of soil property modifications by plants in coastal dunes, which will give guidelines for managing and conserving these ecosystems.
