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Harvesting intensity versus sustainability in Indonesia
Abstract
In East Kalimantan (Indonesia), impacts of conventional (CNV) and reduced-impact logging (RIL) on forest ecosystems were compared on the basis of pre- and post-harvesting stand inventories. There was a positive and significant correlation between the proportion of trees damaged by felling and the density of trees felled. Logging intensity ranged from 1 to 17 trees ha−1(9–247 m3 ha−1) and averaged 9 trees ha−1 (86.9 m3 ha−1). The study has shown that with RIL techniques, logging damage on the original stand can be significantly reduced by 50% compared with conventional logging. However, this 50% reduction in logging damage, was dependent on the felling intensity. With a felling intensity of 8 stems ha−1 or less, RIL techniques only damaged 25% of the original tree population whereas 48% were damaged with conventional techniques. Above this felling intensity (i.e. 8 stems ha−1), the effectiveness of RIL in limiting forest damage was significantly reduced, mainly because of the increasing felling damage. Moreover, the removal of all harvestable timber trees, leaving only few potential crop trees, will result in a seriously depleted residual stand. Because of the high damage involved by high felling intensity, leaving few potential crop trees, and the yield capacity of the remaining stand, acceptable harvesting volume will not be reached within the felling rotation of 35 years. It is concluded that silvicultural system based on diameter limit alone, as is the Indonesian system (TPTI), cannot be compatible with sustainability and more sophisticated harvested-selection rules are needed.
... Significant differences in the individual and sum per tree of root collar damage were found between the subcompartments, with greater damage in Subcompartment 14c. The results of this and previous research show that the greater number of damaged trees was influenced more by the dimensions of the assortments produced [9] than by the intensity of the felling [9,10]. ...
... Significant differences in the individual and sum per tree of root collar damage were found between the subcompartments, with greater damage in Subcompartment 14c. The results of this and previous research show that the greater number of damaged trees was influenced more by the dimensions of the assortments produced [9] than by the intensity of the felling [9,10]. ...
... Different studies have yielded different classifications of injury severity, but all indicate the two most important parameters for assessing the severity of damage: injury depth and injury size [9,10,31,34,48]. The results of this research show a smaller number of trees with injuries in the category of serious damage (>500 cm 2 )-4% of all damaged trees in Subcompartment 14b and 6% of all damaged trees in Subcompartment 14c-in comparison with previous studies, where the prevalence of injuries in the category of serious damage was between 17-40% in the use of partially mechanised harvesting systems [31,34]. ...
This research was conducted to determine the cause, intensity and location of damage (stem, butt end, root collar, root) and the extent of damage to standing trees during felling and processing by an harvester and timber extraction by a forwarder (cut-to-length system). The research was conducted in the central part of the Republic of Croatia in the Management Unit (MU) “Bjelovarska Bilogora” during the thinning of Subcompartment 14b, area of 18.28 ha, in the stand of hornbeam (Carpino betuli—Quercetum roboris fagetosum Rauš 1975), age 70, and of Subcompartment 14c, area of 9.07 ha, in a stand of common beech (Carici pilosae—Fagetum Oberdorfer 1957) aged 79 years. The thinning intensity was 12.13% in Subcompartment 14b and 13.72% in Subcompartment 14c. Field measurements were carried out on sample plots—the first time in 2017 to determine the intensity and characteristics of the damage to standing trees with regard to the cause of the damage (harvester or forwarder), and the second time in 2018 to determine the overall intensity and features of the damage to standing trees after finishing harvesting operations. For all trees remaining in the stand after the harvesting operations, the following were determined: tree species, diameter at breast height (DBH), the position of the tree in the stand depending on the forest traffic infrastructure, and—if damaged—cause of damage, type of damage, the position of damage on the tree, and dimensions of damage. The intensity of the damage was expressed by the ratio of damaged and undamaged trees, with a detailed analysis of bark damage (squeezed-bark damage and peeled-bark injuries). The results of the research indicate the highest prevalence of peeled-bark injuries. In relation to the total number of standing trees, trees with peeled-bark injuries were more represented in Subcompartment 14c (39%) than in Subcompartment 14b (33%). In Subcompartment 14b, the harvester and the forwarder damaged an equal number of trees, while in Subcompartment 14c, the harvester damaged 59% of the damaged trees. In both subcompartments, an average of 83% of (peeled bark) injuries were up to 1.3 m above the ground. In both subcompartments, the most common (67%) were injuries up to 100 cm² in size, for which many authors claim the tree can heal by itself. Given the increasing use of harvester-forwarder systems in deciduous stands and research results that indicate possible damage to standing trees, it is necessary to pay attention to all phases of planning and execution of timber harvesting operations, thus minimising negative effects.
... In spite of evidence that started to accumulate in the 1990s that timber yields declined with each harvest if these minimum guidelines were followed [42][43][44][45][46][47][48][49][50], in 2009 the government changed the regulations to allow increased harvest intensity. For production forests, the minimum cutting diameter was reduced from 50 cm to 40 cm and the minimum cutting cycle duration from 35 to 30 years. ...
... and 8.4.3). The proportion of CARs related to STY did increase over time; FMEs certified within the last three years of the study accounted for 60% of the major STY-related CARs (46), of which 37% were most critical and critical to STY. ...
... There are also several requirements related to field verification of management practices. Given the abundant evidence that compliance with the Indonesian government's minimum forest management rules for its production forests (i.e., a 30-year minimum harvest cycle and a minimum harvest diameter of 40 cm DBH) results in declining yields [42][43][44][45][46][47][48][49][50], we assume that achievement of STY requires lower harvest intensities than the allowed ones and/or application of silvicultural treatments that effectively increase yields [42]. Table 2. Assumptions, indicators and metrics derived from our high-level ToC for STY assurance in managed natural forests in Indonesia (Figure 1). ...
To illustrate the importance of theories-of-change (ToCs) for evaluation of conservation interventions, we consider the global ToC from the Forest Stewardship Council (FSC) and then develop a more explicit ToC focused on the sustained timber yield (STY) aspiration for natural forest management in Indonesia. We use these ToCs to consider certification implementation processes vis-à-vis indicators for STY extracted from FSC’s Indonesian Stewardship Standard that mentions STY explicitly in 45 and implicitly in 21 of 237 indicators. Analysis of 38 audit reports about 23 enterprises (2001–2017) revealed that only 77 of 504 major non-conformities assigned by auditors addressed STY. This apparent lack of attention to STY is surprising given the exhaustion of timber stocks in many production forests and the closure of many forest enterprises over the past two decades, but our ToC reveals numerous unsatisfied and unsatisfiable assumptions in certification that preclude detection of unsustainable harvests. Furthermore, compliance with governmental regulations on harvest intensities does not allow full timber recovery. To sustain yields, logging intensities need to be reduced and/or silvicultural treatments applied to increase yields, both of which reduce short-term profits. Declining yields might be accepted if the capacity of logged forests to grow timber is not impaired, but forest abandonment due to timber stock depletion is worrisome if it fosters illegal forest conversion.
... In this system, little action is taken to reduce forest damage during harvest, thereby causing soil damage and high tree mortality and leaving remaining stands in poor condition (Bertault and Sist 1997;Matricardi et al. 2010). Reduced-impact logging has been globally promoted in response to domestic and international concerns regarding the ecological and economic sustainability of harvesting natural tropical forests (Sist et al. 1998;Dionisio et al. 2017). Reduced-impact logging generally benefits biodiversity and reduces carbon emissions (Miller et al. 2011;Putz et al. 2012) and is increasingly suggested for timber production in the tropical forests of Southeast Asia (Putz et al. 2008). ...
... Reduced-impact logging generally benefits biodiversity and reduces carbon emissions (Miller et al. 2011;Putz et al. 2012) and is increasingly suggested for timber production in the tropical forests of Southeast Asia (Putz et al. 2008). In addition, it incorporates preand post-logging guidelines such as conducting preliminary surveys, employing directional felling, planning skid trails, and using climber cutting methods (Sist et al. 1998). Reduced-impact logging can reduce the overall damage to remaining forests by 30-50% (Bertault and Sist 1997), thereby promoting better stand development. ...
... Illegal logging by local ethnic people (Saunders 2014) continues in both protected and natural production forests as a way to sustain their lives, although they know that they may be fined or sent to prison. The current logging prohibition is negatively affecting sustainable forest management because illegal logging is negatively affecting or killing remaining trees as no care is considered when logging, and no post-logging silvicultural activities are applied to help promote the regrowth (Cannon et al. 1994;Pinard and Putz 1996;Bertault and Sist 1997;Sist et al. 1998;Putz et al. 2008). ...
Most tropical forests outside protected areas have been or will be selectively logged because the timber industry is a main income-generating resource for many developing countries. Therefore, understanding the composition of commercial timber species and logging types is key for sustainable forest management in countries like Vietnam as they move toward fulfilling Reducing Emissions from Deforestation and Forest Degradation (REDD+) agreements. Seven 1-ha plots were surveyed in the Central Highland of Vietnam, and 18 commercial tree species from these plots, whose timber is widely used by local people for housing and furniture making and timber is easily sold at local markets for high prices, were analyzed. In total, 151 tree species with a diameter at breast height (DBH) of ≥ 10 cm were recorded. The 18 commercially valuable species assessed in this study accounted for 33.2% of all stems (total of 524 stems ha⁻¹ for all species), 47.1% of basal area (total of 34.35 m² ha⁻¹ for all species), and 50.8% of aboveground biomass/AGB (total of 262.68 Mg ha⁻¹ for all species). Practicing diameter-limit harvesting of all commercially valuable species with DBH of ≥ 40 cm, which is widely performed in Vietnam, will reduce the number of stems by 7%, basal area by 31.6%, and AGB by 38.2%. Because such harvesting practices cause severe ecological impacts on the remaining forest, logged forests may require > 40 years to recover the structure status of a pre-logged forest. In addition, the recovery of the 18 commercially valuable species may require a much longer time because they comprised 33.2% of stems. Permission for logging natural forests should be given in Vietnam to sustain lives of local communities, where logging has been prohibited. However, alternative harvesting systems, such as reduced-impact logging systems, should be considered. The systems selected must simultaneously generate economic returns for local people and respect the REDD+ agreements with regard to protecting biodiversity and reducing carbon emissions.
... Finally, with detailed harvest plans implemented by trained workers, fewer felled trees are carelessly left in the forest, more timber is recovered from harvested trees due to reduced log breakage and wastage, and there is less collateral forest damage (46). RIL alone does not guarantee that commercial timber yields will be sustained, at least not with currently governmentmandated MCDs (12,13,37). One already mentioned problem is that small canopy gaps do not favor regeneration of lightdemanding commercial timber species. ...
... One already mentioned problem is that small canopy gaps do not favor regeneration of lightdemanding commercial timber species. Another problem is that the benefits of RIL are diminished at logging intensities of >8-10 trees ha −1 or >40 m 3 ha −1 (37). Finally, on steep slopes and in deep swamps where forest management is increasingly relegated due to conversion of forests on more suitable terrain, successful RIL may require switching from dragging logs out of the forest with bulldozers or skidders, which causes substantial soil and collateral forest damage, to extracting logs from the forest with long cables so that heavy machines traverse little of the harvested area (47). ...
What is meant by sustainability depends on what is sustained and at what level. Sustainable forest management, for example, requires maintenance of a variety of values not the least of which is sustained timber yields (STYs). For the 1 Bha of the world's forests subjected to selective or partial logging, failure to maintain yields can be hidden by regulatory requirements and questionable auditing practices such as increasing the number of commercial species with each harvest, reducing the minimum size at which trees can be harvested and accepting logs of lower quality. For assertions of STY to be credible, clarity is needed about all these issues, as well as about the associated ecological and economic tradeoffs. Lack of clarity about sustainability heightens risks of unsubstantiated claims and unseen losses. STY is possible but often requires cutting cycles that are longer and logging intensities that are lower than prescribed by law, as well as effective use of low-impact logging practices and application of silvicultural treatments to promote timber stock recovery. These departures from business-as-usual practices will lower profit margins but generally benefit biodiversity and ecosystem services.
... Among the 119 compartments, 21 were encroached by a total of 336 households in 2013 ( Figure 1). To establish the sample plots, we intentionally selected three compartments (29,46, and 54) where the latest logging operation was conducted in 2011, the frequency of legal logging was higher than the MSS standard 30-year rotation cycle (e.g., logging occurred once in 30 years), and people had encroached and illegally settled (Forest Department, Bago Township, 2013). The Myanmar forest law prohibits the settlement and commercial use of the RF and PPF without permission, while subsistence use is allowed in designated areas [22]. ...
... After legal and illegal logging, tree density and basal area were substantially reduced to 102 ± 57.6 trees ha −1 and 9.7 ± 1.4 m 2 ha −1 in mean ± SD (Table 1), although they were higher than in the study plot of Khai et al. [17] where the values were only 20 trees ha −1 and 4.39 m 2 ha −1 for BA. These stocks are much lower than those in pre-logging conditions in the production forests in Myanmar (193 ± 58.9 and 16.85 ± 3.0 m 2 ha −1 ) [18], as well as in Central Africa (578 ± 42.4 tree ha −1 , 32.6 ± 3.9 m 2 ha −1 ) [28] and in Indonesia (530 ± 71.6 tree ha −1 , 31.5 ± 4.2 m 2 ha −1 ) [29]. These values are also lower than those reported for logged-over forests in other tropical regions; 25.2 m 2 ha −1 in East Kalimantan [30], 26.0 ± 6.4 and 24.1 ± 7.1 m 2 ha −1 in Sarawak, Malaysia [31], and 20.3 and 25.9 m 2 ha −1 in the Brazilian Amazon [32]. ...
The restoration of degraded forests is the focus of global attention. Effective restoration requires information on the condition of degraded forests. This study aimed to understand the conditions of illegally logged stands that had also experienced inappropriately short rotations between legal logging cycles in natural production forests in Myanmar. Four rectangular plots (each 0.64 ha) were established in 2013. The plots included illegally logged stumps in three compartments where the latest legal logging was conducted in 2011 after very short rotations between legal logging cycles (up to five harvests between 1995 and 2011, compared with a recommended 30-year logging cycle). Using data from the field measurements in 2013 on the legal and illegal stumps and living trees, we reconstructed stand structure just before and after legal logging in 2011. Before the legal logging in 2011, there were variations in stand structure and the composition of commercial species among four plots. Illegal logging (14–31 trees ha⁻¹) was much higher than legal logging (0–11 trees ha⁻¹). Illegal logging targeted six to nine species that were suitable for high-quality charcoal from various sized trees, while legal logging targeted one or two timber species with a diameter at breast height (DBH) larger than 58 cm. The number of remaining trees in 2013 ranged from 33 to 181 trees ha⁻¹. There was a negative relationship with the number of bamboo clumps, which varied from 6 to 145 clumps ha⁻¹. Bamboo-dominated stands with a low remaining stock of commercial trees may need active restoration such as bamboo cutting and replanting of commercial species. Bamboo cutting could generate income for the local community.
... Die aufgeführten Holzarten beider Familien sind somit repräsentative Beispiele für die Übernutzung bestimmter selektiv genutzter Wirtschaftsbaumarten (Sist 1998;Sist und Nguyen-Thé 2002;Sist et al. 2003;Grogan et al. 2008;Inada et al. 2017) und illegalen Holzeinschlag , wogegen andere gut verfügbare Hölzer mit vergleichbaren Holzeigenschaften wirtschaftlich ungenutzt bleiben. ...
... , and wood from the representing the assortment of Yellow balau, bangkirai. A recurrent problem in the history of the tropical timber industry is the over exploitation (Sist 1998;Sist and Nguyen-Thé 2002,;Sist et al. 2003;Grogan et al. 2008;Inada et al. 2017) and illegal logging of certain trade assortments such as mahogany or meranti, while other tree species, so-called "lesser known species" with comparable technical properties and sufficient forest availability remain underutilized (Forster et al. 2003;Silva Guzmán et al. 2012). ...
As a consequence of globalized timber markets, overexploitation of primarily tropical tree species and relocation of industrial production facilities, new or unknown wood species, so-called "lesser known species", have been increasingly imported into the European market. Regular evaluations at the Thünen Institute of Wood Research reveal that 20 to 30 "new" timbers (mainly tropical species) are added every year, whereas in many cases their wood and utility properties are largely unknown. As these timbers are often recommended for outdoor use, the determination of the natural durability is of great importance. In this thesis, basic wood anatomical and topochemical analyses (cellular UV-spectroscopy) of lesser known species from Central and South America with special focus on timbers from Mexico and Peru were carried out to study their properties. Natural durability with a quantitative assessment was determined according to the European standard (EN 350-2016); traces of fungal decay were also examined by light and electron microscopy. The anatomical and subcellular characteristics, including a histometric evaluation, of juvenile and adult wood of seven lesser known species (Manilkara zapota, Platymiscium yucatanum, Lonchocarpus castilloi, Roseodendron donnell-smithii, Terminalia buceras, Tabebuia rosea, Lysiloma latisiliquum) from Mexico were studied by light microscopy and X-ray diffraction using the SilviScan®-technique. The purpose was to provide basic data for a detailed differentiation between these two wood tissues.
In conclusion, the anatomical examinations allow a clear identification of these timbers to fulfill the due diligence requirements of the European Timber Trade Regulation (EUTR) and are a useful contribution to the assessment of the wood properties of these lesser known species.
Content:
Publications
I. Wood anatomical and topochemical analyses to characterize juvenile and
adult wood of lesser-known species from Central America (Mexico)
II. Cedrelinga cateniformis (Tornillo, Cedrorana) as substitute for relevant timbers
used for window manufacturing and outdoor application.
III. Die Europäische Holzhandelsverordnung (EUTR) - Anforderungen an die Holzartenbestimmung in der Praxis.
IV. Fasern im Fokus: Holzartenbestimmung von Faserplatten - Erfahrungen aus
den Prüfungen im Kontext der EUTR.
V. Womit grillen wir da eigentlich? Wissenschaftliche Untersuchungen zeigen,
dass viele Chargen zumindest fehlerhaft deklariert sind.
VI. Viele Anfragen zu Bubinga und Palisander: Auswirkungen der neuenCITES-Listungen wichtiger Wirtschaftsbaumarten für die Holzverwendung und den Holzhandel.
... More than 90% of damage was superficial, and 65% of the damage was smaller than 50 cm 2 in size [36]. The percentage of harvested volume is another important aspect directly related to the amount of damage to residual stand [37]; therefore, adequate planning and management of each intervention (silviculture treatment, harvested volume, forest yard organization, etc.) are essential for carrying out sustainable forest operations. In Indonesian forests, Sist et al. [37] indicated that with a felling intensity of 8 stems ha −1 or less, reduced-impact logging (RIL) techniques only damaged 25% of the original tree population while 48% were damaged with conventional techniques. ...
... The percentage of harvested volume is another important aspect directly related to the amount of damage to residual stand [37]; therefore, adequate planning and management of each intervention (silviculture treatment, harvested volume, forest yard organization, etc.) are essential for carrying out sustainable forest operations. In Indonesian forests, Sist et al. [37] indicated that with a felling intensity of 8 stems ha −1 or less, reduced-impact logging (RIL) techniques only damaged 25% of the original tree population while 48% were damaged with conventional techniques. ...
In this study, damage to residual trees during thinning performed by motor-manual felling and whole tree skidding was studied in a loblolly pine (Pinus taeda L.) plantation. Forest intervention was carried out in 2016 and tree wounds were studied and examined over a period of three years. The results indicated that 8% of the residual trees suffered damage, of which 52% was caused by felling operations and 48% by extraction operations. Among the damaged trees, 13% had damage to the root system, 53% to the bole, and 34% to the crown area. The average wound size at the time of occurrence was 71.3 cm². This was found to be reduced to 54.4 cm² after a three year period. Wound intensity decreased with higher wound height and increased size. Three years after wound occurrence, only 6.6% were closed, 90.6% were still open, and 2.8% were decayed. The diameter growth in damaged trees was 1.7% lower than in undamaged trees (p > 0.05). Damage to the root system of residual trees reduced diameter growth by 3% (p < 0.05). Intensive wounds (damaged wood) caused a reduction of 22.7% in diameter growth (p < 0.01). In addition, the diameter growth in trees with decayed wounds was 27.4% lower than unwounded trees (p < 0.01). Pre-harvest planning, directional tree felling, marking of the extraction path before logging operations, employment of skilled logging workers, and post-harvest assessment of damaged residual trees are essential implementations in timber plantations.
... Indonesia's sustainable forest management regulations require post-harvest restoration. Timber harvesters are required to protect seed trees and trees below the legal diameter limit, replant cleared or degraded areas and close access roads to prevent encroachment into logged-over forests (Sheil and Meijaard, 2005;Sist et al., 1998). However, these regulations are often not applied consistently (Sist et al., 1998). ...
... Timber harvesters are required to protect seed trees and trees below the legal diameter limit, replant cleared or degraded areas and close access roads to prevent encroachment into logged-over forests (Sheil and Meijaard, 2005;Sist et al., 1998). However, these regulations are often not applied consistently (Sist et al., 1998). Many of these issues -unclear access rights, rent-seeking, and lack of adherence to sustainable forest management within concessions -were already significant in the period prior to Indonesia's Reformasi (Sunderlin and Resosudarmo, 1996;Potter and Lee, 1998). ...
... From this amount of disturbed soils, 11% to 19% was shallow disturbed and 3% to 8% was deep disturbed. The extent and intensity of soil disturbance caused by forest harvesting operations depend on several factors such as harvest area condition, skill of skidding crew (Nikooy et al. 2010), level of operation planning (Pinard and Putz 1996), forest road density (Iskandar et al. 2006), harvest intensity (Sist et al. 1998), and type of skidding machines (Han and Kellogg 2000). Major studies on soil disturbance in forest harvesting areas focused on selective cutting and ground-based skidding, while data about the effect of thinning intensity on soil disturbance, especially in the Hyrcanian forests, remains scarce. ...
... A decrease in the value and volume of wood and stem deformation are a consequence of wounding (Meadows 1993). Previous studies have demonstrated that even small damage to the bole of residual trees leads to a decrease in future values of residual stands and final products (Verissimo et al. 1992;Pinard et al. 1995;Sist et al. 1998;Tavankar et al. 2017b). ...
Thinning has a crucial role in retaining the future value of stands; hence, excessive soil disturbance and damage to residual trees can diminish thinning advantages. The research aims were to assess soil disturbance and the level of stand damage from thinning operations. Thinning intensity ranged from 8.3% to 19.1% of the standing volume. Soil disturbance and damage level to residual trees, were determined in five young even-aged hardwood stands, using ground-based extraction systems. Tree felling was done by chainsaw, and full trees were extracted by a skidder. Point-transect method and systematic sampling plots were used to characterize soil disturbance and residual trees damage, respectively. Surface of disturbed soil ranged from 14% to 27% and stand damage ranged from 5% to 18% of the residual trees and they were significantly increased by increasing thinning intensity. Soil resistance to penetration at a depth of 0–10 cm in the shallow disturbed (0.39 MPa), deep disturbed (0.52 MPa), and skid trails (0.79 MPa) were increased by 14%, 27%, and 54%, respectively, compared to the undisturbed soils (0.25 MPa). Winching was the main cause of soil disturbance and damage to residual trees. The highest frequency of damage was observed on trees with a dbh class of 20 cm (24.3%). Most of the stand damage occurred on the bole (55%) of trees, with wound sizes ranging from 50 to 350 cm2, and most of the wounds (53%) showed damage to the cambium and wood fibers, at heights of <1 m above the ground line (76%).
... The intensity of official logging in this study (5 trees ha −1 and 25.5 m 3 ha −1 ) is relatively low compared with the maximum ranges reported in the tropics, such as 20 trees ha −1 [30], 70 m 3 ha −1 [28], and 200 m 3 ha −1 [29]. Sist et al. (1998) [31] suggested that the felling intensity of reduced-impact logging must be limited to a maximum of 8 trees ha −1 to reduce logging damage by 50% in comparison with conventional logging. Therefore, the intensity of official logging in this case study may not be the main reason for forest degradation. ...
... The intensity of official logging in this study (5 trees ha −1 and 25.5 m 3 ha −1 ) is relatively low compared with the maximum ranges reported in the tropics, such as 20 trees ha −1 [30], 70 m 3 ha −1 [28], and 200 m 3 ha −1 [29]. Sist et al. (1998) [31] suggested that the felling intensity of reduced-impact logging must be limited to a maximum of 8 trees ha −1 to reduce logging damage by 50% in comparison with conventional logging. Therefore, the intensity of official logging in this case study may not be the main reason for forest degradation. ...
Understanding the stand dynamics of tropical production forests is essential for determining the sustainability of a polycyclic selective logging system, but limited related studies have addressed the impacts of illegal logging over time. Myanmar faces the extensive degradation of traditional production forests with a 160-year logging history, but the cause of this degradation and how to balance legal and/or illegal disturbances with recovery in over-logged forests remain unclear. The present study investigated stand structural changes over 5 years after official legal logging operations using two 1-ha (100 × 100 m) sample plots. For 5 years after logging, the volume of trees with a diameter at breast height (DBH) ≥ 20 cm decreased by 46.0% from 121 to 65.1 m³ ha⁻¹, with a significant loss of the first- and second-grade species group (Tectona grandis Linn. f. and Xylia xylocarpa (Roxb.) Taub.) from 48.3 to 6.8 m³ ha⁻¹. The total tree loss owing to official logging operations, mainly targeting the second- and fourth-grade species group, was 29.3 m³ ha⁻¹. A similar level of total tree loss (28.0 m³ ha⁻¹) was attributed to illegal logging that targeted the first- and second-grade species group. The mean annual recruitment rate of 3.1% was larger than the reported values for tropical forests, but there were no and only 1.5 trees ha⁻¹ recruitments s for T. grandis and X. xylocarpa, respectively. The mean annual mortality rate of 2.5% was within the values reported in the related literature, and the volume loss from the mortality was relatively similar to the gain from the increment of living trees for all species groups. We concluded that the effects of illegal disturbances for 5 years post-harvest were equivalent to those of legal disturbances and larger than those of natural change, and are a major cause of the substantial reduction in stocking levels, especially for commercial species.
... They also correspond with production volume of 38.9 observed in Brazil (West et al. 2014). Higher timber production (50-250 m 3 •ha − 1 •year − 1 ) has been reported by Sist et al. (1998) and Sist et al. (2003aSist et al. ( , 2003b, which, however, investigate earlier stages of timber production. ...
... Scenario LDE 1 is conservative by assuming comparatively low forest harvesting emissions. Larger logging losses (Bertault and Sist 1997;Chapman and Chapman 1997;Sist and Nguyen-Thé 2002;Priyadi et al. 2005 Pinard andPutz 2006;Medjibe et al. 2011) and logging intensities (Sist et al. 1998;Sist et al. 2003aSist et al. , 2003bBischoff et al. 2005) are reported for the Kalimantan. To understand the magnitude of the potential carbon emissions associated with larger logging losses, the study defined additional scenarios that anticipate emissions that exceed the emissions of the conservative Scenario 1. Scenarios LDE 2 and LDE 3 assume larger logging intensities and larger harvesting-related carbon losses. ...
The knowledge gap regarding post-logging carbon recovery by increased growth is becoming more crucial to understand the significant contribution of forest to climate change mitigation. We assessed the ability of tropical forests in Indonesia to recover carbon following conventional logging. We evaluated carbon re-growth of 10,415 trees in permanent sample plots (PSPs) in East Kalimantan. Four different post-harvesting silvicultural treatments including liberation, refining, thinning, and control were applied in the PSPs. We estimated the carbon recovery period using three different scenarios of total carbon losses due to logging. In the first scenario, we used an existing factor of logging damage and increased it for assuming the range of carbon losses due to different logging practices. Under the existing conventional logging practice, the concession annually emits 51.18 tC∙ha− 1, of which 16.8% are extracted from the forest as raw timber, 38% are logging losses, and 45.2% are emissions due to infrastructure development for logging operation. Increasing the logging damage factor two and three times led to an increase in carbon emission to 70.76 and 90.34 tC∙ha− 1, respectively. The recovery time of the aboveground carbon is 26 years in Scenario 1, 36 years in Scenario 2, and 46 years in Scenario 3. We found no significant effect of the silvicultural treatment type on carbon recovery, but significant effect of the sites was observed. We found that the time taken to restore the carbon to the level found in undisturbed forests is considerably longer than the current intervention cycles. The time needed to recover biomass and carbon-stock noticeably depends on the intensity of logging interventions, demonstrating the benefits of using improved harvesting e.g., reduced impact logging to reduce emissions. The study found that site variability has a significant effect on the carbon recovery time. Different silvicultural treatments, on the other hand, have no effect on the recovery time. The study suggests that it is not appropriate to establish an intervention cycle based on arbitrary choice; the time between interventions must be based on logging losses and site specific growth potential to ensure sustainable management of forests.
... 36 Klassen (1996), Elias (1997), Elias et al. (2001). 37 Bertault and Sist (1997), Sist et al. (1998), and Ruslandi et al. (2017). ...
... Krisnawati and Wahjono (2010);Ruslandi et al. (2017b). 60 Eg.,Sist et al. (1998);Favrichon et al. (2001);Krisnawati and Wahjono (2010);Ruslandi et al. (2017b). ...
The report provides historical analysis of USAID/Indonesia's longstanding Natural Resources Management program, which has continued over nearly 30 years addressing many issues in the terrestrial and marine environments in Indonesia. The report further provides recommendations for future programming of environmental assistance to Indonesia
... The amount or level of damage caused to residual trees during selective cutting treatment and cable skidder logging operations depends on a number of factors, including forest characteristics, such as: the amount of timber removed during harvesting ( Sist et al. 1998;Fjeld and Granhus 1998), stand density and basal area (Bettinger et al. 1998), skid-trail spacing (Gullison and Hardner 1993;Vasiliauskas 2001) and road density ( Iskandar et al. 2006). It is also important to highlight that all the damage may not always be caused by logging activities-a recent study confirmed that on steep slopes, a considerable number of trees may be damaged by rock fall ( Mihelič et al. 2018). ...
... One of the reasons for this could have been the very small number of trees harvested in FA3, albeit of very large sizes. Again, high harvesting intensity, expressed in the number of trees, might explain the higher rate of damage ( Sist et al. 1998;Fjeld and Granhus 1998). ...
Damage to the remaining stand on steep terrain can be quite severe and is usually difficult to control during winching. Timber skidding, especially by agricultural tractor, is a common solution in small-scale forestry. One of the factors influencing remaining stand damage is winching on steep terrain, although, to date, this has only been studied in general. Limiting stand damage is possible when the factors causing the damage are well-known. Therefore, the aim of this paper was to study in detail the impact of slope steepness on different types of damage in the stand after winching, focusing in particular on: (1) the share of trees with damage (including natural regeneration), (2) the size of the wound, (3) the number of wounds per tree, (4) wound intensity, and (5) the position of the wound on a tree. Field observations were carried out in three beech (two in Italy and one in Iran) and two pine stands (in Italy), in which four classes of slope steepness were selected for each stand. After timber harvesting, damage to the remaining stand as well as to any natural regeneration was recorded. It was found that the share of wounded trees was directly related to slope steepness, although this was less obvious in the natural regeneration. On steeper slopes, there were larger wounds and, on average, there were more wounds per tree. Wound intensity also depended on the gradient of the slope. The size, understood as diameter at breast height, of the remaining trees on the slopes also had an impact on the wound characteristics: on thicker trees, bigger wounds were detected and a higher number of them. However, thicker trees were less often wounded. Wound position on a tree did not depend on slope steepness but it may have been related to stand density and size of winched timber.
... Some management systems in Brazil have low harvest intensities, such as a community management system with intensities as low as 4.82 m 3 ha −1 [74], but most Brazilian projects harvest on the order of 30 m 3 ha −1 (e.g., [75]), and, prior to Brazil's 1997 regulations on forest management, some projects harvested as much as 50 m 3 ha −1 [76]. At the other end of the spectrum, in Southeast Asia, where the percentage of the trees that are commercially valuable is much higher than in Amazonia, a management system harvested an average of 86.9 m 3 ha −1 , and some areas were harvested at up to 247 m 3 ha −1 [77]. ...
Tropical forest management has a potential role in forest conservation if it is sustainable. This study of a forest under management in Bolivian Amazonia strongly suggests that the management project is not sustainable and that no potential changes in management would be likely to make it so. In a 216.41 ha harvested area, 278 commercial trees from 10 families, 15 genera, and 15 species were measured. The density of commercial species with diameter at breast height (DBH) ≥ 50 cm was 1.28 trees ha⁻¹, and the harvestable commercial volume was 12.40 m³ ha⁻¹. Due to market restrictions, the actual amounts harvested were much lower: 96 trees were harvested with commercial boles totaling 2.7 m³ ha⁻¹. Of the total impact on biomass and carbon (above- and belowground), the logs removed from the area represented only 13.4%, while 86.6% was from losses in the forest as follows: 14.5% from the stumps, crowns, and roots of harvested trees (DBH ≥ 50 cm) plus 72.1% from the trees (DBH ≥ 10 cm) in the forest lost to roads, log landings, and skid tracks and the gap openings caused by felling the harvested trees. The estimated expenses exceeded the gross revenue of the management company (USD 519.15 ha⁻¹), a fact confirmed by the company’s subsequent bankruptcy. The project’s low harvest intensity reduces the environmental impact per hectare but increases the impact per cubic meter of wood harvested because producing a given volume of wood requires disturbing a larger area and because more kilometers of access roads and skid tracks have to be installed to extract a given volume of wood. Because many costs are fixed regardless of harvest intensity, small harvest volume can render such projects financially unfeasible, increasing the likelihood that they will be abandoned and not provide long-term “sustainable” forest protection. However, this does not mean that higher harvest intensity results in sustainability, as other constraints apply to high-intensity projects. We conclude that conservation alternatives to maintain the forest would be more beneficial than management for timber.
... Today, there is no transparent, systematic, and robust ground-based assessment of the state of forest degradation caused by logging activities, especially in Central Africa, where forest disturbances occur on a smaller scale than on other continents, mainly because of a low logging intensity (1-4 trees.ha − 1 ) (Durrieu de Madron et al., 2000) in comparison to that in South-East Asia (Sist et al., 1998) and South America (Sist and Ferreira, 2007) (15-18 trees.ha − 1 ). ...
Forest degradation is a major threat to tropical forests, and effective monitoring using remotely sensed data is subject to significant challenges. In particular, consistent methods for detecting subtle changes in the forest canopy structure caused by selective logging are lacking. Here, using a unique dataset collected in southeastern Cameroon, covering over 22,000 ha of monthly harvesting areas, >6000 locations of harvested trees, and an independent canopy gap dataset developed from an uninhabited aerial vehicle flight (UAV; RGB camera) of approximately 1500 ha, a new method was designed to monitor canopy disturbance and logging intensity in Central Africa. Using Sentinel-1 synthetic aperture radar (SAR) data, the method was conceptualised using a two-step, two-scale approach, which better matched logging practices. First, (non-)harvesting activity areas were identified using textural indices at a spatial resolution of 300 m (step 1), and within these harvesting activity areas, canopy gaps were detected at a resolution of 10 m (step 2). Both steps were based on monthly differences in the Sentinel-1 SAR time series computed using the average of the 12 months preceding and the average of the three months following the month of interest. This method identified harvesting activity areas (step 1 at 300 m resolution) of over 12,004 km 2 with high accuracy (omission and commission errors for both classes ≤0.05) and, within them, detected canopy gaps (step 2 at 10 m resolution) with a global accuracy of 0.89. Although some canopy gaps were subject to omission and commission errors (0.39 and 0.05, respectively), this method yielded better results than other available approaches. Compared to the UAV canopy gaps, this method detected most of the small gaps (≤ 500 m 2), which represent 80% of all disturbed areas, whereas other available approaches missed at least 70% of these and consequently missed most of the disturbance events occurring in a selectively logged forest. Furthermore, the predictions were correlated with logging intensity, i.e., the number of trees and volume cut per hectare, which are two important criteria for assessing the sustainability of logging activities. This two-step two-scale method for short-term, monthly monitoring of logging disturbances and intensity has strong practical implications for forest administration and certification bodies in Central Africa.
... Hasil tinjauan mengindikasikan bahwa intensitas penebangan sebesar 8 pohon/ha dapat dijadikan sebagai ambang batas intensitas penebangan pada teknik pemanenan hutan yang berwawasan lingkungan. Sist et al. (1998) menyatakan bahwa jika intensitas penebangan hutan lebih besar dari 8 pohon/ha, maka efektivitas teknik RIL akan berkurang, meninggalkan tegakan masa depan yang sedikit dan kapasitas hasil yang rendah. Lebih lanjut Khai et al. (2020) dan Matangaran et al. (2019) melaporkan bahwa hubungan antara intensitas penebangan hutan dengan kerusakan tegakan tinggal adalah linear. ...
Forest harvesting in the natural production forest management in Indonesia is mostly carried out using conventional logging techniques and causes serious damage to residual stands and soil resources. One of the efforts made to reduce this environmental damage is the application of reduced impact logging (RIL) techniques. This study aimed to collect and analyze research results related to the damage to residual stands caused by RIL in the natural production forest management in Indonesia. This study used a systematic review method. A systematic literature search was carried out at data sources such as Google Scholar, Research Gate, Science Direct, and SINTA, which were published between 1996-2021. All studies reported that applying RIL techniques can reduce the damage to the residual stands.
... Although previous studies have investigated the effect of SL and/or RIL on the sustainability of timber resources (Huth and Ditzer 2001;Inada et al. 2017, Samsudin andKassim 2010;Sist et al. 1998;Sist, Picard et al. 2003), the effects of logging on forest recovery remain largely undetermined. It is specifically needed to understand if the current harvesting cycle is appropriate for sustainable forestry. ...
In Sarawak, Malaysia, logging is conducted with a 25-year harvesting cycle; however, it remains largely unclear if this cycle length is sufficient for forest recovery. This study aims to investigate how the structure of logged forests recovered along the periods after logging. We conducted this study in the Anap-Muput Forest Management Unit (AMFMU), Sarawak. We first established permanent sample plots with different logging history; that is, from 5 years to more than 37 years after the most recent logging. Using the various sample plots, we assessed the stem density, basal area (BA), proportion of dipterocarps, growth and mortality. To compare the forest structure of the logged over forests with that of primary forests, we used our previous data of a primary forest in Batang Ai National Park. We found significant differences in the stem density, total BA, and the proportion of dipterocarp among the plots. Generally, the stem density and total BA increased with the period after logging and decreased with diameter at breast height (DBH) size classes, except of tree of ≥60 cm DBH in several plots. The growth rates and mortalities were higher in more recent logged forests. These results indicated that logged forest was recovering with periods after logging partly because of higher growth rate; however, even in a forest of 37 years after logging, the forest structure was not fully recovered compared to the primary forest. Thus, we concluded that a 25-year harvesting cycle in the selective logging system would not be sufficient for the AMFMU forest to recover. We further need other effective strategies with systematic monitoring.
... Learning from various studies in natural forests shows that the application of RIL techniques can increase the efficiency of wood utilization by an average of 12% [108] and reduce residual damage by 13.62% [109,110]. From a conservation perspective, silvicultural techniques of selective logging guarantee more forest sustainability [111] because it can increase environmental stability through the presence of remaining stands resulting in new regeneration [112]. Subtropical forests revealed that new regeneration is significant in establishing vegetation, thereby contributing to biodiversity and continued timber production [113]. ...
Indonesia has around 4000 wood species, and 10% (400) of species are categorized as commercial wood. One species is kayu kuku (Pericopsis mooniana Thwaites), native to Southeast Sulawesi. This species is considered a fancy wood used for sawn timber, veneer, plywood, carving, and furniture. The high demand for wood caused excessive logging and threatened its sustainability. In addition, planting P. mooniana has presented several challenges, including seedling production, viability and germination rate, nursery technology, and silviculture techniques. As a result, the genera of Pericopsis, including P. elata (Europe), P. mooniana (Sri Lanka), and P. angolenses (Africa), have been listed in the Convention on International Trade in Endangered Species (CITES) Appendix. Based on The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, P. mooniana is categorized as Vulnerable (A1cd). This conservation status has raised issues regarding its biodiversity, conservation, and sustainability in the near future. This paper aims to review the conservation of potential and endangered species of P. mooniana and highlight some efforts for its species conservation and sustainable use in Indonesia. The method used is a systematic literature review based on P. mooniana’s publication derived from various reputable journal sources and additional literature sources. The results revealed that the future demand for P. mooniana still increases significantly due to its excellent wood characteristics. This high demand should be balanced with both silviculture techniques and conservation efforts. The silviculture of P. mooniana has been improved through seed storage technology, improved viability and germination rates, proper micro and macro propagation, applying hormones, in vitro seed storage, improved nursery technology, and harvesting techniques. P. mooniana conservation can be conducted with both in situ and ex situ conservation efforts. In situ conservation is carried out by protecting its mother trees in natural conditions (i.e., Lamedae Nature Reserve) for producing good quality seeds and seedlings. Ex situ conservation is realized by planting seeds and seedlings to produce more wood through rehabilitating and restoring critical forests and lands due to its ability to adapt to marginal land and mitigate climate change. Other actions required for supporting ex situ conservation are preventing illegal logging, regeneration, conservation education, reforestation, agroforestry system applied in private and community lands, and industrial forest plantations.
... Para promover a conservação da floresta e possibilitar um rendimento sustentado da produção madeireira, no final da década de 1970 foi introduzido na Amazônia brasileira a Exploração de Impacto Reduzido (EIR) (J.N.M.Silva comunicação pessoal 2020). Essa pratica é caracterizada por um conjunto de procedimentos técnicos pré e pós-exploratórios destinados a conservar a estrutura e as funções ecológicas das florestas, reduzir os danos ambientais, custos operacionais e desperdícios da atividade de manejo florestal (HENDRISON, 1990;PINARD;PUTS, 1996;SIST et al., 1998;HOLMES et al., 2002, SABOGAL et al., 2000ZARIN et al., 2007;HIRAI et al., 2012). Dentre os principais procedimentos estão o corte de cipós, a liberação de copas para maior captação de luz, a condução da regeneração natural e o enriquecimento em clareiras (SILVA, 1989;YARED, 1993;SABOGAL et al., 2000;GOMES et al., 2010). ...
... RIL techniques applied in the study followed the harvesting guidelines published in [7]. To evaluate the effectiveness of RIL, pre-and post-harvest inventory for trees was conducted to calculate damage level, area of disclosure and production potential. ...
Despite increased recognition of the value provided by forests, the tropical forest potential continued to be seriously degraded, especially by overexploitation. In the field of harvesting, achieving sustainable forest management requires environmentally responsible logging, hence the growing interest in reduced impact logging (RIL) as an alternative strategy to promoting good forestry practices be expected can continue to fulfil the functions of forest ecosystems. The study was conducted in 100 ha of the first cutting cycle and 200 ha of the second cutting cycle of 22 years logged over the forest in Indonesia Borneo. The degraded level is measured based on disclosed area, while potential production of the residual stand is predicted by using growth increment data from a permanent sample plot. Harvest intensity influence significantly to residual stand condition with a positive correlation. Potential production of residual trees in the first logged-over forest after 35 years is almost recovered then can be achieved sustainable yield. It means that 22 years is not a sustainable cutting cycle. The disclosure area after the second logging was high of 66.89 to 69.36. Potential production of residual trees was very low and need 35.5 to 42.8 years to recover, however, the cutting cycle needs a longer time to achieve sustainable forest management as long as 57.3 to 63.2 years. Based on this study, regulation of reduced cutting cycle on logged-over forest after 20 years is not recommended to implement in natural forests.
... The overexploitation of natural forests in Indonesia and Malaysia, combined with the ban on log exports that has fostered the development of a powerful timber industry based on a low price for wood resources, was the first step in this accumulation (Barr 2002). In this context of overexploitation, cutting cycles of 35 years are too short to allow commercial volume recovery (Sist et al. 1998). Such an immobilization of natural capital is considered as far too long by companies. ...
Converting forest ecosystems to other land uses has major negative consequences for the climate, biodiversity and human well-being. Several international initiatives have emerged to address these issues. Initially focused on narrow technical dimensions of forest management and setting up protected areas, the perspective was extended to forest-related issues, such as agricultural practices, and policy responses were designed. The issue of economic incentives became central in the construction of an international regime for protecting forests. REDD+, an international results-based payment scheme, became emblematic of this incentive-based architecture currently being actively promoted by donors.
So far, none of these initiatives has succeeded in curbing deforestation and the conversion of natural ecosystems to artificialized areas. Diagnoses of the “forest crisis” are generally correct, but they often overlook major political economy issues, such as the fact that governments are not benevolent institutions acting for the common welfare of their people and that urban elites have little interest in the fate of forest-dependent people, who are not that numerous and often voiceless. Endeavours to tackle the forest crisis without questioning the unabated global demand for biomass, energy and agricultural land, and the rules of international trade, seem illusory. Results-based payments have to be rethought, without tying one’s hands with an automatic payment procedure based on an unverifiable level/reference scenario. The only meaningful criterion is the coherence of public policies that potentially have impacts on forests. Renewed results-based payments must therefore give priority to investment and to a joint agenda merging food security and forest protection.
... The overexploitation of natural forests in Indonesia and Malaysia, combined with the ban on log exports that has fostered the development of a powerful timber industry based on a low price for wood resources, was the first step in this accumulation (Barr 2002). In this context of overexploitation, cutting cycles of 35 years are too short to allow commercial volume recovery (Sist et al. 1998). Such an immobilization of natural capital is considered as far too long by companies. ...
... Forest disturbance and biodiversity losses in these reserves are entirely dependent on the management regime, with reduced impact logging (RIL) methods using reduced harvesting rates (<30 m 3 timber per ha) and best practice harvesting techniques (e.g., directional felling, reduced skid trail construction, limitations on extractable timber; Pinard et al., 1995). As such, RIL results in lower biodiversity loss (Bicknell et al., 2014) and 50% less damage to remaining forests than conventional logging techniques (Sist et al., 1998). Malaysian and Indonesian commitments to increase sustainably certified forest reserves has led to a sharp increase in RIL use throughout Borneo (Sabah Forestry Department, 2009;Ellis et al., 2019). ...
Borneo's amphibians face an uncertain future due to high levels of forest degradation and a paucity of data for effective conservation management. Several studies identified strong species–habitat relationships in pristine and conventionally logged forests. However, these studies did not account for detectability or habitat associations in sustainably managed forest reserves. Here, we determined detectability and species habitat relationships in stream amphibians within the Deramakot forest reserve, a reduced impact logging concession in the Malaysian state of Sabah, northern Borneo. We analyzed data for 10 stream species collected along 32 stream transects. An occupancy modeling framework was used to determine the climatological, temporal, and environmental covariates associated with detection and occupancy probabilities. We identified high variability in detection probability between species, including significant associations with moon phase (six species), time since sunset (five species), humidity (five species), rainfall (four species), and temperature (three species). Stream slope and volume provided by far the best predictors of occurrence, with significant positive or negative associations with the occupancy of six species each. These associations were more similar to those found in pristine compared with conventionally logged habitats. The highly variable detectability associations within our amphibian community suggest a level of temporal separation in regard to activity and breeding phenology in these species. This stresses the importance of accounting for detection probability via surveying sites across varying climatic/temporal conditions to obtain a representative sample of amphibian communities in pristine and disturbed tropical forests.
... Felling intensity is one of significant factors, which affects the damage intensity of the remaining stand. Some authors state that the percentage of stand damage increases with the increasing harvesting intensity [25][26][27]. The number of felled trees was determined by counting all fresh stumps. ...
The paper deals with the damage of the remaining stand and soil caused by harvesting using three ground-based forest operations methods (harvester-forwarder/cable skidder/animal-tractor). It compares the impact of the most common harvesting technologies applied in Slovakia and in Central Europe and thus contributes with valuable information to the knowledge on the suitability of their application in forests stands dominated by broadleaved tree species. Harvesting was performed in five forest stands located at the University Forest Enterprise of Technical University in Zvolen in central Slovakia from August to October 2019. Damage to remaining trees was assessed from the point of its size, type, and position of damage along stem. We expected lower damage of remaining trees in stands where harvesters were used because of the applied cut-to-length short wood system and fully mechanized harvesting system. In addition, we examined soil bulk density and soil moisture content in ruts, space between ruts, and in undisturbed stand to reveal the impact of harvesting machinery on soil. We expected greater soil bulk densities and lower soil moisture content in these stands due to the greatest weight of harvesters and in ruts created by machinery compared with undisturbed stand soil. The highest percentage of damaged remaining trees equal to 20.47% and 23.36% was recorded for harvester forest operations, followed by skidder (19.44%) and animal forest operations with 19.86% and 14.47%. Factorial ANOVA confirmed significant higher soil compaction in stands where harvesters were used (higer bulk density) than in stands where skidding was performed with the skidder and animal power. Higher soil moisture content was recorded in ruts created by harvesters and the skidder. The lowest soil moisture content was in undisturbed stands irrespective of the applied forest operation method.
... While the planted trees 310 remain standing, the biodiversity effects of this intervention are surprisingly minor (Berry et al. 2010; 311 Ansell et al. 2011). Unfortunately, when these planted trees are harvested after 25-30 years, the 312logging intensity will be so high that the effects will be devastating regardless of the harvesting 313 techniques employed (e.g.,Sist et al. 1998). ...
When net deforestation declines in the tropics, attention will be drawn to the composition and structure of the retained, restored, invaded, and created forests. At that point the seemingly inexorable trends towards increased intensities of exploitation and management will be recognized as having taken their tolls of biodiversity and other forest values. Celebrations when a country passes the “forest transition” (i.e., suffers no net deforestation) will then be tempered by realization that what has been accepted as “forest” spans the gamut from short-rotation mono-clonal stands of genetically engineered trees to fully protected old growth natural forest. With management intensification, climate change, species introductions, landscape fragmentation, fire, and shifts in economics and governance, forests will vary along gradients of biodiversity, novelty of composition, stature, permanence, and the relative roles of natural and anthropogenic forces. Management intensity will increase with the increased availability of financial capital associated with economic globalization, scarcity of wood and other forest products, demand for biofuels, improved governance (e.g., security of property rights), improved accessibility, and technological innovations that lead to new markets for forest products. In a few places the trend towards land-use intensification will be counterbalanced by recognition of the many benefits of natural and semi-natural forests, especially where forest-fate determiners are compensated for revenues foregone from not intensifying management. Land-use practices informed by research will help minimize the tradeoffs between the financial profits from forest management and the benefits of retention of biodiversity and the full range of environmental services.
... A basic reason why my efforts and those of many other scientists failed to improve the fates of forests in Borneo was our collective belief that the data we provided would influence decisions and change behaviors. We showed, for example, that timber yields could be sustained only if harvest cycles were extended to 40-60 years and not the 25-30 years allowed by the government (e.g., Vanclay 1994;Sist et al. 1998). Equally disregarded was research that demonstrated the benefits of planned harvests by trained crews (e.g., Pinard and Putz 1996) and the acceleration of timber volume recovery after silvicultural treatments (e.g., Wadsworth and Zweede 2006). ...
Borneo differs fundamentally from Canada, but reflections on the struggles to improve the fates of its tropical rain forests may resonate with people engaged in the same struggles on the other side of the Pacific. I frame these reflections around the question of why my efforts as a researcher in Borneo failed to cause a change from predatory logging of old growth to conservation through improved forest management. Perhaps my most fundamental mistake was unwillingness to recognize the immense profitability of forest liquidation through multiple-premature re-entry logging, especially when followed by conversion to plantations of African oil palm or Australian acacias. Superimposed on the high opportunity costs of conservation were governance failures that diminished the effectiveness of policies set by government as well as those set by certifiers of responsible management. Conservation of the mostly remote, flooded, and steep hinterlands still covered by forest will benefit from acknowledgment of the internationally recognized intrinsic land rights of Borneo's indigenous peoples combined with full economic cost accounting of the consequences of forest degradation and conversion. Given the global importance of old growth in Borneo, Canada, and elsewhere, global funding for conservation should be made available with safeguards such as UNESCO Biosphere designations. Keywords: failure of research to have impacts, natural forest management, old-growth, primary forest, reduced-impact logging, sustainable forest management RÉSUMÉ Bornéo est à tout compte fait totalement différent du Canada, mais les observations tirées des combats pour assurer la pérennité de ses forêts tropicales peuvent éveiller des échos chez les personnes impliquées dans les mêmes combats de l'autre côté du Pacifique. J'ai recadré ces observations face à la question que je soulevais à savoir pourquoi mes efforts en tant que chercheur sur place à Bornéo n'ont pas pu empêcher de transformer l'exploitation illégale des forêts anciennes en un mode de conservation découlant d'un aménagement forestier accru. Fort probablement que ma plus grande erreur fondamentale a été ma réticence à reconnaître le niveau élevé de profitabilité issus de la liquidation des forêts à la suite d'une série d'extractions hâtives, surtout dans le cas où s'en suit la conversion des forêts en plantations de palmier à huile africain ou d'acacias australien. À cela, il faut ajouter les coûts d'opportunité élevés reliés à la conservation là où les échecs des autorités diminuent l'efficacité des politiques mises en place par le gouvernement, ainsi que celles établies par les agences de certification de l'aménagement forestier responsable. La conservation des forêts la plupart du temps retrou-vées dans les zones inondées et escarpées de l'arrière-pays bénéficiera des droits intrinsèques des nations indigènes de Bornéo reconnus par l'ensemble des nations, en plus de la comptabilisation complète des coûts économiques découlant de la dégradation et de la conversion des forêts. Étant donné l'importance mondiale des forêts anciennes à Bornéo, au Canada et ailleurs dans le monde, le financement international de la conservation devrait être accessible selon des balises établies telles les désignations de la biosphère de l'UNESCO. Mots clés : absence de recherche sur les impacts, aménagement des forêts naturelles, forêt ancienne, forêt primaire, exploitation forestière à impact réduit, aménagement forestier durable
... Legendă: a) importanţa relativă a serviciilor ecosistemice indiferent de categorie, b) importanţa relativă a serviciilor ecosistemice de provizionare, c) importanţa relativă a serviciilor ecosistemice de reglare, d) importanţa relativă a serviciilor ecosistemice culturale (unde importanţa relativă poate avea valori între 0.1 şi 1)Consecinţele asupra mediului relaţionate cu extracţia exagerată a lemnului într-o zonă dată pot fi, printre altele, pierderea diversităţii biologice, pierderea suprafeţelor păduroase, eroziunea terenului şi contaminarea resurselor de apă (IUCN, 1996) aspecte care pot fi evitate prin apelarea la ultimele iniţiative ce vizează îmbunătăţirea practicilor de utilizare a resurselor naturale(Daily et al., 1997). Acestea includ conservarea diversităţii biologice şi menţinerea bunurilor şi serviciilor oferite de mediu, pe care pădurile le oferă în mod natural(Oliver et al., 1992;Sist et al., 1998;Bocco et al., 2000). Pe de altă parte, peisajul susţine formarea şi prosperitatea comunităţilor locale(Rodriguez, 2018) ale căror locuitori pot opera ca promovatori ai protecţiei biologice(Bocco et al., 2000). ...
Ecosystems ensure a flow of multiple benefits or services (ES) that are useful for mankind, which depends on their state and on a given social context. Assessment by steps such as the identification and evaluation of ES through stakeholders’ perception allows assessing different options relating to flow and demand, so the valuation of ES is considered to be an important aspect of planning and management. The evaluation of ecosystem services is usually shaped around the following dimensions or perspectives: ecological, economic and social. Therefore, it allows to identify the main services and the components of ecosystems - or land uses - that provide them (ecological dimension), but it also analyzes the perception of the users or stakeholders (social dimension) and translates (transforms) these benefits in economic terms through application of different methods of economic valuation. The ecosystems and services they provide should be addressed based on the perceptions, necessities and interest of the users or beneficiaries, who perceive the existence and importance of the services differently as an effect of variations of their socio-economic context, familiarity with the ecosystem, belief and religion. Consequently, to ensure a continuous flow of ES, it is necessary to complement land use management systems with information gained through assessment of relevant ES (tangible and non-tangible) by the stakeholders. In this regard, the willingness to pay (WTP) is a reference value that users assign to environmental attributes and/or their improvements such as the conservation or restoration activities; within the environmental improvements, the activities of protection or conservation have a high importance because their implementation ensures a sustainable flow of ES.
In Ecuador, absence of studies related to evaluation of natural resources has prevented the identification of importance level of ecosystems and their services by the users which is a key information for decision-making (laws) and management (operational procedures and rules). As a consequence, the primary (native) forest has decreased in terms of coverage due to indiscriminate logging, change in land use and productive activities (ranching, mining, oil extraction and tourism). In the “Simón Bolívar” parish (Pastaza Province), which covers a representative area of the rainforest, some fragile ecosystems require the implementation of conservation and protection activities, because they provide important services for the local development. Nevertheless, most of the area of this parish is not included in a protection or conservation system, resulting in an acute lack of policies and public funds, a fact that limits a proper management and protection of the native forests and complementary resources. At the parish level, only some fragile ecosystems, environmental components and few ecosystem services have been identified, a situation that has caused serious deficiencies in the few programs of environmental management that are currently implemented, especially by an absence of conservation activities.
The core objectives of an evaluation of natural resources and their services are (i) to shape and implement sustainable land-use systems through the measure of profits that could be derived from the conservation, protection and/or restoration of ecosystems, (ii) to implement policies relating to territorial organization, conservation and sustainability, or even (iii) to establish payments for environmental services. Based on the above arguments, this work aimed to evaluate the capacity of the Ecuadorian Amazonian Rainforest to Provide Ecosystem Services, by the means of evaluating the plant uses, capacity to provide products and services, as well as the perception on the existing landscape management systems in the view of local stakeholders. The obtained information is important in complementing the existing (limited) databases and statistics on the natural capital and ES, and it gives a point of reference for the establishment of policies and local programs to favor the conservation of forests. The core components of this research were the following: (i) identification of ES, (ii) analysis of local population perception on the flow of ES by regular approaches and by visual preferences and (iii) evaluation of commitment of locals to financially support conservation measures using state-of-art techniques.
... The environmental consequences of the increasing extraction of timber in the area may be, among others, the loss of biological diversity, increased deforestation, and promotion of erosion and contamination of water bodies (IUCN, 1996) which could be avoided by using the latest initiatives aiming to improve the practice of natural resources utilization (Daily et al., 1997). These include the preservation of biological diversity and the maintenance of environmental goods and services that the forest naturally provides (Oliver et al., 1992;Sist et al., 1998;Bocco et al., 2000). On the other hand, the landscape sustains the formation of indigenous communities (Rodriguez, 2018) whose inhabitants can operate as promoters of biological protection (Bocco et al., 2000). ...
Ecosystems ensure a flow of multiple benefits or services (ES) that are useful for mankind, which depends on their state and on a given social context. Assessment by steps such as the identification and evaluation of ES through stakeholders’ perception allows assessing different options relating to flow and demand, so the valuation of ES is considered to be an important aspect of planning and management. The evaluation of ecosystem services is usually shaped around the following dimensions or perspectives: ecological, economic and social. Therefore, it allows to identify the main services and the components of ecosystems - or land uses - that provide them (ecological dimension), but it also analyzes the perception of the users or stakeholders (social dimension) and translates (transforms) these benefits in economic terms through application of different methods of economic valuation. The ecosystems and services they provide should be addressed based on the perceptions, necessities and interest of the users or beneficiaries, who perceive the existence and importance of the services differently as an effect of variations of their socio-economic context, familiarity with the ecosystem, belief and religion. Consequently, to ensure a continuous flow of ES, it is necessary to complement land use management systems with information gained through assessment of relevant ES (tangible and non-tangible) by the stakeholders. In this regard, the willingness to pay (WTP) is a reference value that users assign to environmental attributes and/or their improvements such as the conservation or restoration activities; within the environmental improvements, the activities of protection or conservation have a high importance because their implementation ensures a sustainable flow of ES.
In Ecuador, absence of studies related to evaluation of natural resources has prevented the identification of importance level of ecosystems and their services by the users which is a key information for decision-making (laws) and management (operational procedures and rules). As a consequence, the primary (native) forest has decreased in terms of coverage due to indiscriminate logging, change in land use and productive activities (ranching, mining, oil extraction and tourism). In the “Simón Bolívar” parish (Pastaza Province), which covers a representative area of the rainforest, some fragile ecosystems require the implementation of conservation and protection activities, because they provide important services for the local development. Nevertheless, most of the area of this parish is not included in a protection or conservation system, resulting in an acute lack of policies and public funds, a fact that limits a proper management and protection of the native forests and complementary resources. At the parish level, only some fragile ecosystems, environmental components and few ecosystem services have been identified, a situation that has caused serious deficiencies in the few programs of environmental management that are currently implemented, especially by an absence of conservation activities.
The core objectives of an evaluation of natural resources and their services are (i) to shape and implement sustainable land-use systems through the measure of profits that could be derived from the conservation, protection and/or restoration of ecosystems, (ii) to implement policies relating to territorial organization, conservation and sustainability, or even (iii) to establish payments for environmental services. Based on the above arguments, this work aimed to evaluate the capacity of the Ecuadorian Amazonian Rainforest to Provide Ecosystem Services, by the means of evaluating the plant uses, capacity to provide products and services, as well as the perception on the existing landscape management systems in the view of local stakeholders. The obtained information is important in complementing the existing (limited) databases and statistics on the natural capital and ES, and it gives a point of reference for the establishment of policies and local programs to favor the conservation of forests. The core components of this research were the following: (i) identification of ES, (ii) analysis of local population perception on the flow of ES by regular approaches and by visual preferences and (iii) evaluation of commitment of locals to financially support conservation measures using state-of-art techniques.
... Natural tropical rainforest in eastern Borneo, Indonesia, has been logged with selective cutting system since 1970. The cutting intensity that applied in the region was high, i.e. more than 10 trees per ha (Sist et al. 1998;Budiaman and Pradata 2013). Thus, there is a high potential threat to the invertebrate's community due to logging in the area. ...
Budiaman A, Haneda NF, Indahwati, Febrian D, Rahmah LN. 2020. Temporal effects of cutting intensity on Diptera assemblages in eastern Borneo rainforest Indonesia. Biodiversitas 21: 1074-1081. Studies on the effects of varying cutting intensity on the abundance and species richness of Diptera in tropical rainforest are limited, particularly in Southeast Asia region. The aim of the study was to assess the temporal effect of cutting intensity on Diptera community in tropical rainforest in the eastern Borneo rainforest, Indonesia, which was logged using the Indonesian Selective Cutting and Planting system. The field study was carried out in 2016. Responses of Diptera to the Indonesian Selective Cutting and Planting systems in the eastern Borneo rainforest, Indonesia were examined. We compared the abundance and morphospecies composition of Diptera before cutting and after cutting at three different treatments: low cutting intensity, medium cutting intensity and high cutting intensity. Diptera was collected using a malaise trap. Selective cutting of tropical rainforest altered biodiversity of Diptera. The abundance and morphospecies composition of Diptera were greater after cutting than before cutting at all cutting intensities. Our study showed that cutting intensity did not significantly affect the abundance and morphospecies composition of Diptera. Results of the study clearly indicated that the percentage of forest canopy cover could be a single predictor for abundance and morphospecies composition of Diptera in the natural rainforest of eastern Borneo, Indonesia.
... A basic reason why my efforts and those of many other scientists failed to improve the fates of forests in Borneo was our collective belief that the data we provided would influence decisions and change behaviors. We showed, for example, that timber yields could be sustained only if harvest cycles were extended to 40-60 years and not the 25-30 years allowed by the government (e.g., Vanclay 1994;Sist et al. 1998). Equally disregarded was research that demonstrated the benefits of planned harvests by trained crews (e.g., Pinard and Putz 1996) and the acceleration of timber volume recovery after silvicultural treatments (e.g., Wadsworth and Zweede 2006). ...
Borneo differs fundamentally from Canada, but reflections on the struggles to improve the fates of its tropical rain forests may resonate with people engaged in the same struggles on the other side of the Pacific. I frame these reflections around the question of why my efforts as a researcher in Borneo failed to cause a change from predatory logging of old growth to conservation through improved forest management. Perhaps my most fundamental mistake was unwillingness to recognize the immense profitability of forest liquidation through multiple-premature re-entry logging, especially when followed by conversion to plantations of African oil palm or Australian acacias. Superimposed on the high opportunity costs of conservation were governance failures that diminished the effectiveness of policies set by government as well as those set by certifiers of responsible management. Conservation of the mostly remote, flooded, and steep hinterlands still covered by forest will benefit from acknowledgment of the internationally recognized intrinsic land rights of Borneo’s indigenous peoples combined with full economic cost accounting of the consequences of forest degradation and conversion. Given the global importance of old growth in Borneo, Canada, and elsewhere, global funding for conservation should be made available with safeguards such as UNESCO Biosphere designations.
... Both legal and illegal logging activities are harmful and disruptive to forest conservation in that both cause rapid deforestation and forest degradation. Even legal methods like the Indonesian Selective Cutting System (TPTI) require a longer rotation (cutting down and then growing to re-cut) and often companies neglect re-planting trees within that forest area (Sist et al., 1998). Creating protected forest areas helps to manage and balance the natural biodiversity within forest ecosystems but these areas are separate from those specifically designated for commercial purposes (Bettinger et al., 2017). ...
Gunung Palung National Park in Indonesian Borneo, home to 2,500 Bornean orangutans (Pongo pygmaeus ssp. wurmbii), suffers from severe deforestation that is caused by illegal logging. This article aims to analyze the success of an innovative entrepreneurship program in reducing illegal logging in Gunung Palung National Park. This program combines voluntary chainsaw buybacks with capital investment for former loggers to launch a business of their choice. To analyze the success of this entrepreneurship program, we measured two parameters: (1) transitions of former loggers to sustainable alternative livelihoods and (2) reductions in the number of loggers who log actively inside the park. The average monthly income for participating business partners was 2,923,333 rupiah or 240 for established partners who had participated for more than one year. This income is about the minimum wage for the local area. The failure rate of the program—defined as the partners that returned to logging—was only 6%, or 3 out of 50 partners. Successful forest conservation, however, requires addressing additional factors beyond reducing the access to logging equipment.
... Aboveground living carbon (AGC) typically declines with logging intensity (Gerwing, 2002;Martin et al., 2015;Rozak et al., 2018;Zhou et al., 2013). The amount of necromass and trees damaged by logging usually temporarily increases with logging intensity and can represent significant amounts of total C stocks in logged forests (Gerwing, 2002;Rozak et al., 2018;Sist et al., 1998). Logging intensity was also found to be the main factor explaining the variability in belowground living carbon (BGC) stocks (i.e. ...
Forest degradation in the tropics is generating large carbon (C) emissions. In tropical Asia, logging is the main driver of forest degradation. For effective implementation of REDD+ projects in logged forests in Southeast Asia, the impacts of logging on forest C stocks need to be assessed. Here, we assess C stocks in logged lowland forests in central Vietnam and explore correlations between logging intensity, soil, topography and living aboveground carbon (AGC) stocks. We present an approach to estimate historical logging intensities for the prevalent situation when complete records on logging history are unavailable. Landsat analysis and participatory mapping were used to quantify the density of historical disturbances, used as a proxy of logging intensities in the area. Carbon in AGC, dead wood, belowground carbon (BGC) and soil (SOC) was measured in twenty-four 0.25 ha plots that vary in logging intensity, and data on recent logging, soil properties, elevation and slope were also collected. Heavily logged forests stored only half the amount of AGC of stems ≥10 cm dbh as lightly logged forests, mainly due to a reduction in the number of large (≥60 cm dbh) trees. Carbon in AGC of small trees (5-10 cm dbh), dead wood and BGC comprised only small fractions of total C stocks, while SOC in the topsoil of 0-30 cm depth stored ~50% of total C stocks. Combining logging intensities with soil and topographic data showed that logging intensity was the main factor explaining the variability in AGC. Our research shows large reductions in AGC in medium and heavily logged forests. It highlights the critical importance of conserving big trees to maintain high forest C stocks and accounting for SOC in total C stock estimates.
... Shorea representing the assortment of Yellow balau, bangkirai. A recurrent problem in the history of the tropical timber industry is the over exploitation (Sist et al. 1998, Sist and Nguyen-Thé 2002, Sist et al. 2003, Grogan et al. 2008, Günter et al. 2011, Inada et al. 2017) and illegal logging (Grossheim 2011) of certain trade assortments such as mahogany or meranti, while other tree species, so-called "lesser known species" with comparable technical properties and sufficient forest availability remain underutilized (Foerster et al. 2003, Silva-Guzmán 2012. ...
Cedrelinga cateniformis (tornillo) is a timber species of the South American Amazon Basin. In its natural distribution area, the wood has various local uses, such as furniture, art work, door and window frames, and light construction. In order to promote this lesser known species for high valued applications on the international market, wood anatomical, topochemical and physical/mechanical studies were carried out to characterize the wood properties. The topochemical distribution of the lignin and phenolic extractives in the tissue were studied by means of cellular UV microspectrophotometry (UMSP). The results of the structural and topochemical analyses were compared with the interrelation of certain anatomical and subcellular structures as well as the chemical composition with regard to the physical and mechanical properties. The natural durability of the mature heartwood was analyzed according to the European Standards and is resulting in a durability class 1 against basidiomycetes. Based on the findings of the comprehensive investigations concerning physical and biological features, e.g. the dimensional stability and durability, Cedrelinga cateniformis is ideally suited as a substitute for overexploited tropical woods currently used in Europe for wooden window frames and other above ground outdoor applications and thus can contribute to increase the value-added production in Peruvian forests.
... Nevertheless, the growing social demand for timber forest products is covered by an increase in the volume of wood obtained from natural and planted forests [29], while the environmental consequences of the increasing extraction of timber in the area may be, among others, the loss of biological diversity, increased deforestation, promotion of erosion, and contamination of water bodies [42], which could be avoided by using the latest initiatives aiming to improve the practice of natural resources utilization [20]. These include the conservation of biological diversity, as well as the maintenance of environmental goods and services that the forest naturally provides [7], [58], [66]. On the other hand, the landscape sustains the formation of indigenous communities [64] whose inhabitants can operate as promoters of biological protection [7]. ...
The Ecuadorian Amazon region is one of the areas characterized by the greatest biodiversity worldwide. The ecosystems from the area provide many benefits to the local communities in the form of goods and services. Despite the predominance of native forests in the Pastaza Province, a deforestation rate of 7.7% and changes in land use have been recorded lately due to population growth, the reconfiguration of consumption patterns, an increase in the export of agricultural products, changes in forest legislation, agrarian reforms, and the oil extraction industry. Most likely, these changes will affect the local populations and their interaction with the local landscapes, with the poorest ones being the most affected. For these reasons, this study evaluated the use and importance of ecosystem services in the area from the local inhabitants' perspective by conducting a quantitative survey, followed by spatial scaling. While the findings indicate different importance patterns associated with different types of land uses and potential benefits, the native forests and their associated cultural services were found to be the most important for the locals. This was even more important as the spatial scaling showed the predominance of native forests and their associated services in the area. The results of this study may support a participatory approach in designing local strategies and land use policies.
... However, the practice of selective logging is not well controlled, often leading to extensive forest degradation and deforestation (Asner et al. 2005). Such unregulated selective logging usually damages more than 50% of the original forest biomass, causes soil disturbances (Cannon et al. 1994;Pinard and Putz 1996;Bertault and Sist 1997;Sist et al. 1998), and damages tree species diversity, composition, and its spatial structure. Much attention has been paid to understanding logging impacts on tree species diversity per stand or species composition per stand. ...
We studied the impacts of selective logging on the spatial structure of tree species composition in the tropical rain forest of Sabah, Malaysia. We established 50 20-m radius plots (0.12 ha in area) across primary to highly degraded forests in each of two logging concessions with distances in between any two plots ranging from 0.2 to 40 km. In addition, we established one 100 × 200-m plot in each of primary, reduced-impact logged, and conventionally logged forest in other two logging concessions, and each plot was divided into 40 × 30-m quadrats (0.12 ha in area) for the further analysis of the spatial structure at the scale of less than 200 m. A decline of species-compositional similarity with increasing in-between distance was found in primary and moderately logged forest at both larger and smaller than 0.2-km scale. Such a spatial structure could not be detected in heavily logged forests at both scales. The heavily logged forests were rather characterized by mosaics of remnant stands and regenerating patches of pioneer species, leading to a high spatial variance of species composition without the distance-dependent spatial structure. Accordingly, high-impact conventional logging damages the distance-dependent spatial structure of species composition in canopy tree communities by creating random vegetation patches, while reduced-impact logging can maintain the spatial structure.
... Initiatives to systematise selective logging were already in place from the late 1990s. These initiatives helped to develop tools and protocols for selective logging, including the RIL pocket book, specific RIL guidelines for dipterocarp forests (Sist et al., 1998), principles and practices of forest harvesting in Indonesia (2000) and RIL Guidelines for Indonesia in 2001 (Elias et al., 2001). A number of projects invested money and effort to improve the practice but poor logging practices and inefficient timber processing are still considered threats for Indonesia's forests (Blaser et al., 2011). ...
... When felling is based entirely on tree size, all tree species above the cut-size limit are usually harvested (Villela et al. 2006). Harvest intensity per se depends on the quantity of timber trees above the cut-size limit, averaging 10 -17 trees per hectare in densely wooded forests (Sist et al. 1998;Putz et al. 2012). ...
... This aggregation means that values for intensity that are averaged over large areas often poorly reflect conditions on the ground. For example, in 32 plots of 1 ha set up prior to logging in East Kalimantan, Indonesia, (Sist et al., 1998) reported that logging intensities averaged 86.9 m 3 ha −1 (nine trees ha −1 ) but ranged 9-247 m 3 ha −1 with 1-17 trees ha −1 harvested. In Gabon, where overall logging intensities averaged 8.11 m 3 ha −1 and 0.82 trees ha −1 , five of the ten 1 ha plots established in the logging area yielded no timber, and two of those were also not traversed by skid trails (Medjibe et al., 2011). ...
The selective logging that characterizes most timber extraction operations in the tropics leaves large patches of logging blocks (i. e., areas allocated for harvesting) intact, with no direct impacts of the harvest. For example, in the ~10,000 ha we sampled in 48 forest management enterprises in Africa (Gabon, Republic of Congo, and the Democratic Republic of Congo), Indonesia, Suriname, and Mexico, an average of 57% (range 22–97%) of the area in logging blocks was not directly affected by timber harvests. The proportion of intact forest within logging blocks decreased very slightly with increases in harvest intensity in the accessed portion of the logging blocks (9–86 m3 ha−1) but decreased strongly with harvest intensity in entire logging blocks (0.3–48.2 m3 ha−1). More forest was left intact in areas farther from roads, on slopes >40%, and within 25 m of perennial streams, but the effect sizes of each of these variables was small (~8%). It is less clear how much of the intact forest left after one harvest will remain intact through the next. Conservation benefits without reductions in timber yields will derive from better management planning so that sensitive and ecologically critical areas, such as steep slopes and riparian buffers, constitute permanent reserves of intact forest in selectively logged landscapes in the tropics.
... Thus, the value of logged tropical forests for conservation is increased (Edwards et al. 2014b). The selective management system is arguably the best silvicultural intervention for tropical forests where only a selected number of trees will be harvested, usually in a range of 8-15 trees ha -1 (Sist et al. 1998;Pinard et al. 2000). Okuda et al. (2003) highlighted the importance of knowledge of the effects of logging on stand structure, floristic composition and species diversity to sustainably manage a forest silviculturally and ecologically. ...
The mountain ecosystem is a hotspot of biodiversity and provides a significant contribution to the humans’ livelihoods. However, there is still a lack of information regarding floral diversity and how it has been affected due to a logging operation in Sarawak. A study was conducted to determine vegetation recovery at the Heart of Borneo conservation area at different elevations: 750–1200 m (S1), 1200–1500 m (S2) and >1500 m (S3). A total of 891 trees were enumerated. The trees comprised 55 families, 98 genera and 203 species. The lowest elevation site, S1, contained the highest number of species (117) and families (42), while the highest elevation site, S3, contained the lowest diversity (25 families and 59 species). A similar forest structure was recorded, whereby diameter at breast height (dbh), basal area and height decreased as elevation increased. The most speciose families in S1 were Dipterocarpaceae (11 species) and Lauraceae (10 species), while Lauraceae and Fagaceae were the dominant tree families at S2 and S3. Secondary tree species are still abundantly found in the logged plots, especially at S2 (45.5%), indicating that after 30 years, these stands are still in the recovery stages. The logged plots retained typical secondary forest appearances with lower canopy diameters and heights and dbh than the unlogged forest. Although the species richness approached that of the unlogged plots, especially at S1 (90.9%) and S3 (94.9%), there were still major differences in the floristic compositions between logged and unlogged plots (35.4%, 21.5% and 44.7% for S1, S2 and S3, respectively). Although potential seed sources were in close proximity, succession at S2 has proceeded much slower than at S1 and S3. Lower concentrations of soil nutrients, especially N, may be the main reason for the slow recovery. In conclusion, the results suggested that the selectively logged forest at the Payeh Maga Highland required more than three decades to recover and achieve a climate forest stage.
... Podmladak u blizini prosjeka za izvlačenje i traktorskih vlaka uglavnom trpi najveće štete (Stokes et al., 2009). Neki važniji faktori koji imaju uticaj na oštećenje cjelokupne sastojine tokom prebirnih sječa su sljedeći: stepen planiranja sječa (Pinard & Putz, 1996), intenzitet sječa (Sist et al., 1998), zapremina sastojine (Sist et al., 2003), sezona sječe (Limbeck-Lilienau, 2003), mehanizacija koja se koristi (Han i Kellogg, 2000), gustina traktorskih vlaka (Iskandar et al., 2006), sastojinske karakteristike i iskustvo radnog osoblja (Pinard et al., 1995). U suštini, eksploatacija šumskih ekosistema sa nedovoljnim planiranjem radova, nepravilnim tehnologijama iskorišćavanja i nedovoljnom kontrolom tokom izvođenja radova ima za rezultat teške negativne posljedice po sam podmladak, odnosno prirodnu obnovu šumskih sastojina (Rushton et al., 2003). ...
Ulasci u intervalima od deset godina u jednu istu sastojinu, što čini osnovu prebirnog gazdovanja, otvarajumogućnosti za štete po sve njene elemente, prvenstveno od strane mehanizacije. Fokus ovogistraživanja jeste štetan uticaj prebirnih sječa (sječe i izrade i prve faze transporta) na sam podmladak.Ogledne površine koje su postavljene na tri lokacije u okviru sastojine (traktorska vlaka, neposrednopored vlake i na 10 m od vlake) i na kojima je izvršen pregled podmlatka koji se na njima nalazio,omogućile su da se dođe do izvjesnih zaključaka o brojnosti i zdravstvenom stanju mladih biljaka.Naime, rezultati su pokazali da su generalno najveće štete na podmlatku neposredno na traktorskojvlaci, što je uzrokovalo da je na toj lokaciji i najmanja njegova brojnost i najlošije zdravstveno stanje.Podmladak neposredno pored vlake je u nešto boljem stanju kada su u pitanju ova tri faktora, dok jepodmladak na udaljenosti od 10 m od vlake pokazao najbolji kvalitet i najveću brojnost, a sve to iz razlogašto je na ovoj lokaciji dosta manji štetan uticaj mehanizacije. Isto tako, sa udaljavanjem od stovarišta(početka vlake) za sve tri lokacije istraživanja, utvrđeno je da se kvalitet podmlađivanja povećava, štoje uglavnom prouzrokovano opadanjem intenziteta šteta od mehanizovanih sredstava. Ovo poboljšanjestanja podmlatka sa udaljavanjem od početka vlake jasno je vidljivo na samoj vlaci i pored vlake, dok jena 10 m od vlake ova progresija slabijeg intenziteta.
... Initiatives to systematise selective logging were already in place from the late 1990s. These initiatives helped to develop tools and protocols for selective logging, including the RIL pocket book, specific RIL guidelines for dipterocarp forests (Sist et al., 1998), principles and practices of forest harvesting in Indonesia (2000) and RIL Guidelines for Indonesia in 2001 (Elias et al., 2001). A number of projects invested money and effort to improve the practice but poor logging practices and inefficient timber processing are still considered threats for Indonesia's forests (Blaser et al., 2011). ...
Selective logging is the dominant timber harvesting practice in natural tropical forests. Considering its scale and its contribution to forest management outcome, efficient management of selective logging is crucial to address challenges associated with timber demand, carbon sequestration and biodiversity conservation. Ongoing selective logging has been a key reason for forest degradation despite a set of recommended practices such as reduced-impact logging. With the objective of drawing the attention of scholars and policy makers to answer the question why effectiveness of selective logging practice is still an issue, we tracked the trend and pattern of scholarly research related to the impact of selective logging. Using a systematic review of literature, we explored and discussed the possible factors hindering implementation of improved forest harvesting practices and the overall knowledge gaps yet not explored in this field of research. This review found consensus among scholars that implementation of improved forest harvesting is still rare despite the constant efforts made by researchers since the 1970s. Based on the review findings we concluded that concentration of research on specific countries, insufficient coverage of diversified forest dimensions/thematic areas, and higher concerns relating to ecological impacts of forest management are the reasons behind poor adoption of research outcomes of improved logging practices. Likewise, their implementation is further hindered by limited attention to the interests and needs of the forest managers/owners, lack of coordination and collaboration among stakeholders and negligible support to develop stakeholders' capacity. Our review suggests a broadening of the geographical and thematic focus of the study as well as a consideration of effective engagement and capacity development of the forest managers/ owners and stakeholders in selective logging policies and practices.
Actions to impede the impact of timber extraction are possible both during logging operations and when such operations terminate. Water bars across log haulage tracks and abandoned roads can inhibit gully development, divert water away from roads into vegetated areas and trap sediment. Buffer strips along streams can prevent some eroded material from getting into streams and interrupt flows from gullies emanating from tree-felling and log landing operations. More general reduced impact logging operations can make further reductions in the hydrological and erosional impacts of selective timber harvesting. Plot experiments showed that water bars (earth barriers to downslope runoff bulldozed up at the end of logging) permitted more luxuriant vegetation regrowth and much less erosion of disused skid trails. In a buffer strip evaluation experiment, peak sediment concentrations were about a quarter of those in the Baru catchment that underwent normal selective logging. A reduced impact logging experiment at Danum decreased the percentage of the logged area that was disturbed by about 60%, the disturbance caused by roads and landings by about 27% and that by skid trails by about 70%. The means of managing tropical rainforest lands wisely do exist. Soil can be conserved. The lessons from Danum are that after logging, water movement and pathways should be turned back as far as possible to the conditions in the natural forest by encouraging infiltration and avoiding gully extension.
Examining ecosystem functioning of logged-over forests requires a quantitative trait-based monitoring approach, in addition to a taxonomic approach, which allows for evaluation of the accompanying shifts in species traits and functional composition. Our study evaluated forest regrowth after different logging and thinning techniques applied to 60 one-hectare forest subplots in East Kalimantan that were logged using selective conventional and reduced-impact techniques. We used seven functional traits to compare the short-term (∼1-year) and longer-term (∼10-year) changes in functional diversity and composition of the forest. Both conventional and reduced impact logging resulted in higher functional diversity after 10 years, but forest functional traits shifted away from those observed in unlogged (control) subplots. Reduced-impact logging led to smaller deviations in functional composition compared to unlogged forest. We found that low-intensity reduced-impact logging, i.e., <3 m² ha⁻¹ (equivalent to 5 trees ha⁻¹ or approximately 42 m³ ha⁻¹), maintained functional diversity equivalent to unlogged forest measured in 12 one-hectare control plots. Selectively logged forest subplots with liberation thinnings increased functional diversity while leaving the trait composition unchanged. Thinned subplots exhibited higher functional diversity than the un-thinned subplots and greater similarity to unlogged forest. However, high-intensity thinning, i.e., >10 m² ha⁻¹, resulted in large functional traits shifts away from unlogged forest. Our study suggests that preserving the original forest functionality, i.e., by applying low intensity, reduced-impact logging and thinning operations, represents a sustainable strategy for long-term tropical forest management.
Saat ini, kegiatan pemanenan kayu telah menerapkan teknologi pembalakan berdampak rendah (Reduced Impact Logging/RIL) tetapi masih terjadi limbah pemanenan kayu rata-rata 17%. Limbah tersebut belum dimanfaatkan karena diduga mahalnya biaya produksi karena belum diketahuinya metode pemanenan kayu yang tepat. Penelitian ini bertujuan untuk mendapatkan data dan informasi produktivitas dan biaya penyaradan limbah pemanenan kayu pada areal hutan alam pegunungan. Hasil penelitian menunjukkan bahwa biaya pengeluaran limbah pemanenan kayu metode tree length logging pada jarak sarad ± 2 hm sebesar Rp 35.693/m3. tetapi menggunakan metode konvensional adalah Rp 349.125/m3 belum termasuk DR dan PSDH. Metode tree length logging selain dapat mengeluarkan kayu utama juga limbah pemanenan kayu batang bebas cabang (BBC) dan batang di atas cabang (BAC) sampi TPn juga meningkatkan efisiensi pemanfaatan kayu. Tetapi, penerapan metode tree length logging mengakibatkan menurunnya produktivitas penebangan 16,47% dan penyaradan sebesar 14,41% pada jarak sarad rata-rata ± 2 hm. Produktivitas rata-rata penebangan metode konvensional adalah 62,514 m3/jam sedangkan metode tree length logging 52,289 m3/jam. Produktivitas rata-rata penyaradan metode tree length logging sebesar 17,301 m3/jam tetapi metode konvensional 18,249 m3/jam. Agar metode tree length logging dapat dimplementasikan di lapangan perlu dilakukan perubahan tariff upah penebangan dan penyaradan sesuai dengan tingkat penurunan produktivitas kerja.
Tropical ecosystems house a significant proportion of global biodiversity. To understand how these ecosystems function we need to appreciate not only what plants, animals and microbes they contain, but also how they interact with each other. This volume, first published in 2005, synthesises the state of knowledge in this area, with chapters providing reviews or case studies drawn from research conducted in both Old and New World tropics and including biotic interactions among taxa at all trophic levels. In most chapters plants (typically trees) are the starting point, but, taken together, the chapters consider interactions of plants with other plants, with micro-organisms and with animals, and the inter-relationships of human-induced disturbance with interactions among species. An underlying theme of the volume is the attempt to understand the maintenance of high diversity in tropical regions, which remains one of the most significant unexplained observations in ecological studies.
Logged-over forests comprise a large proportion of tropical forest landscapes, but questions remain on how to fully describe and understand the regeneration of these forests and which selective logging and silvicultural interventions are best for maintaining biological diversity. We used a phylogenetic approach to capture changes on the evolutionary diversity, structure and composition of 72-one-hectare forest subplots in East Kalimantan that were logged using conventional (CL) and reduced-impact (RIL) techniques, including post-logging silvicultural interventions by reducing stem density (thinning), shortly after (on average 18 months) and 10 years after treatments. Both CL and RIL techniques initially decreased phylogenetic diversity, but after a decade of succession the phylogenetic diversity levels were no longer different from unlogged forests (Controls). Thinning through poison-notching non-commercial trees led to an increase in phylogenetic diversity after a decade of succession. Mean evolutionary relatedness, as measured by the Net Relatedness Index, initially decreased in logged forests, possibly because of harvest of closely related dipterocarp species, but returned to initial levels after a decade. Regardless of silvicultural interventions 10 years after logging had no effect on the mean evolutionary relatedness of the trees in the communities at both time intervals.
Both CL and RIL techniques increased the phylogenetic composition dissimilarity with unlogged forest, with increasing logging intensity resulting in increasingly larger effects, although the changes were smaller for RIL. Phylogenetic composition only became dissimilar from unlogged forest after a decade of succession, when the logging intensity was above 4 m² ha⁻¹ for both CL and RIL, equivalent to 8 trees ha⁻¹ or 68 m³ ha⁻¹. Post-logging silvicultural interventions started to cause changes in phylogenetic composition when the basal area was reduced by thinning by more than 10 m² ha⁻¹. The rapid recovery of phylogenetic diversity, community structure and, to a lesser extent composition after logging and thinning confirms that tropical forests are resilient to a single logging cycle. With low-intensity logging of less than 4 m² ha⁻¹, RIL techniques appear to facilitate phylogenetic structure and compositional recovery to levels not different from unlogged forest after 10 years of succession, especially when combined with post-logging silvicultural intervention with a basal area reduction by thinning of less than 10 m² ha⁻¹. However, it remains to be seen whether forests will respond similarly to a second logging cycle.
Orman yolları, sürdürülebilir
ormancılık operasyonları için en
önemli alt yapı tesisleri olup ana
orman yolları ve tali orman yolları
olmak üzere iki sınıfa ayrılırlar. Bu
yollardan farklı teknik özelliklere sahip,
değişik amaçlar için kısa ya da uzun
zaman kullanılmak üzere açılmış,
üst yapısı bulunmayan patikalar da
mevcuttur. Patikalar, uzun zaman
önce ulaşımın sağlanması amacıyla
yapılmış ve halen varlıklarını kısmen
devam ettirmekte olan kadim patikalar
ve orman bakımı, odun transportu
ya da orman yangınlarıyla mücadele
gibi ormancılık faaliyetlerinin
gerçekleştirilmesi amacıyla açılan yeni
patikalar olmak üzere iki tiptir. Bu
çalışmada orman bakımı faaliyetleri
için açılan bakım patikaları, odun
transportunda kullanılan sürütme
şeritleri ve kablo şeritleri ile orman
yangınlarıyla mücadelede kullanılan
yangın emniyet yol ve şeritleri
incelenmiştir.
The Reduced-Impact Logging (RIL) Project started in August 1992 when New England Electric System provided funds to Innoprise Corporation Sendirian Berhad (ICSB, Sabah, Malaysia) to implement a set of reduced-impact logging guidelines in 1400 hectares (ha) of its concession. The principal goal of the project was to reduce damage to both the soil and the residual stand during selective logging by harvest planning, prefelling vine cutting, directional felling, and other environmentally sound management techniques. The harvesting guidelines developed and adopted by the RIL project specify practices expected to reduce logging damage, thereby retaining more carbon in living trees and promoting post-logging biomass increments. -from Authors
Global concern over rising atmospheric concentrations of carbon dioxide is stimulating development and implementation of policies aimed at reducing net greenhouse gas emissions by enhancing carbon sinks. One option for reducing net emissions is to lessen damage to residual forests during selective logging, thereby retaining additional carbon in biomass. A pilot carbon offset project was initiated in Sabah, Malaysia, in 1992 in which a power company provided funds to a timber concessionaire to implement guidelines aimed at reducing logging damage; in doing so, the utility gained potential credit towards future emissions reduction requirements. To quantify the carbon retained due to this effort, we compared dipterocarp forests logged according to reduced-impact logging guidelines with forests logged by conventional methods in terms of the above- and below-ground biomass both before and after logging. Prior to logging, the forest stored approximately 400 Mg biomass ha-1, 17 percent of which was belowground. High volumes of timber were removed from both of the logging areas (mean CNV = 154, RIL = 104 m3ha-1). Forty-one percent of the unharvested trees
Although logging ceased in the tropical rainforests of north Queensland following their World Heritage Listing in 1988, they provide a good basis for simulation studies on sustainability of timber harvesting as reliable logging records, inventory and growth data are available. A growth model for these forests has been developed and published. The growth model is dynamic, responding to changes in stand density, composition and management history. A harvesting simulator predicts the trees removed by selection logging, and predicts changes on the residual stand. Simulation studies employ cutting cycle analysis and yield scheduling to demonstrate the sustainability of harvesting. These studies indicate that selection harvesting could sustain a viable timber harvest of about 60 000 m3 year−1. These results are indicative rather than definitive, as the model has not yet been formally validated with independent data.
"Claim of sustainability are virtually impossible to prove but enough is known about tropical forest ecology and silviculture to protect ecosystem functions and maintain biodiversity while still deriving financial profirs from logging .Rapid improvements in long-term forest production will derive from better planning of harvesting operations and stand improvement treatments. Lack of good management plans generally results in logging practices that destroy natural regeneration and increase forest susceptibility to soil loss, wildfires,and weed infestations. Participation of forest managers, timber importers, researchers, and environmentalists in the development of methods for assessing the social and ecological impacts of tropical forestry operations inspires hope for sustainability."
Amazon logging has been traditionally restricted to floodplain forests, but the Amazon highway system now permits the logging of the interfluvial forest. In an assessment of a mechanized, selective logging operation in Para state, eastern Amazonia, 30-50 m of wood volume were removed per ha. This amounted to four to eight trees per ha, or one to two percent of all tree stems 10 cm dbh. The profits were considerable (the land owner made 9000 in the logging of 52 ha over a 21-day period); but in the process of extraction, 26 percent of all the pre-harvest trees 10 cm dbh were killed or damaged (e.g., 12% lost their crowns, 11% were uprooted by bulldozers, and 3% suffered substantial bark scarring). Total canopy cover was reduced by almost one-half (from 80$% to 45%) and 8% of the forest area was scarred by logging roads. If logging continues at its present rate, all of Para state could easily be logged within the next 80 years. Strategies to promote the responsible use of Para's forest do exist; all that is lacking is the political will to bring them to life.
To understand the relationship between the dynamics of tropical rain forests and the population processes of individual species, data are needed on the rates at which trees grow, die, and establish. Data on the family Moraceae have been extracted from long-term forestry studies in Sarawak, on the northwest coast of Borneo, an area at the center of species richness of Old World tropical forests. These data can also be combined with forest maps and logging studies to investigate the importance of competition and disturbance in controlling tree growth. Tree populations of Moraceae species had mean annual diameter increments of between 0.4 and 3 mm/yr. Growth rates increased two to six times in the 1st and 2nd yr following (selective) logging, but began to decline somewhat in the 3rd and 4th yr. Growth rate variation among trees in a population was considerable, with most trees showing little or no growth, and a few, high growth rates. Saplings of Artocarpus species increased in diameter at the same mean rate as adult trees. Annual mortality rates were low in primary forest, typically
Growth and yield models provide decision-support for forest-level management planning. DIPSIM is an individual-tree growth model developed to serve as a planning tool for the commercial dipterocarp forests of Sabah. It uses forest inventory data to predict annual growth in terms of stem numbers, volume, and basal area. The process of growth prediction involves the simulation of diameter growth, mortality, and recruitment. The model accounts for four major factors which influence tree growth: species, tree size, site condition, and competition. Twenty growth functions representing 20 growth groups were developed: 11 functions for the dipterocarps and 9 for the non-dipterocarps. An optional harvesting module simulates harvesting prescriptions. A case study is given to illustrate the application of DIPSIM to forest management planning, with emphasis on yield regulation.
The concept of perturbations is introduced to the general physics student using a forced anharmonic oscillator constructed on a linear air track. The interaction between a bar magnet mounted atop the glider and two Umagnets supplies the perturbation. The general characteristics of the system are described, and plots of the amplitude versus driving frequency showing a “jump” effect are presented. The advantage of the system described is that all components of the system are open to study by the student.
Plots of 1.25 and 11.25 ha were enumerated for trees and lianes ≥10 cm and trees ≥70 cm dbh respectively along a line transect in the Lopé Reserve, Gabon. In the small plot 511 trees and lianes of 116 species were found, and 175 trees of 48 species were present in the large plot. The plots were then subject to commercial mechanised logging and the enumerations were repeated once logging had been completed. The extraction rate was two trees ha−1 and in the large plot a total of 31 (17.7%) trees representing 20.6% of the total original basal area died. Incidental damage in the small plot resulted in the loss of 10.8% of trees and lianes present, and 12.9% of the original basal area. Canopy cover was reduced by 10%. Damage levels were low compared with figures from most other tropical regions. The relevance of these figures to forest management in Gabon are discussed.
In the Paragominas region of eastern Amazonia, we compared the damage in unplanned and planned logging operations associated with each of five logging phases: (1) tree felling, (2) machine maneuvering to attach felled boles to chokers, (3) skidding boles to log landings, (4) constructing log landings and (5) constructing logging roads. Planned logging was conducted with a rubber-wheeled skidder or a bulldozer equipped with a winch, while unplanned logging was conducted with a bulldozer not equipped with a winch.
The paper presents a forest management planning concept presently under development at the Forestry Department of the State of Sabah, Malaysia. This planning procedure forms part of a comprehensive forest management system directed towards the sustainable production of timber and other produce in the commercial dipterocarp forests which over an area of about 2.5 million ha, or approximately 40% of the total landmass of the State. In order to ensure application of this system, different field techniques are presently tested in an area of 55 000 ha logged-over forests (Deramakot Forest Reserve). The planning procedure is an amalgamation of methods successfully applied for sustained yield management in many other parts of the world and consists of a combination of enterprise-level and compartment-level management planning, the latter being a component which so far has not been applied in Sabah. This procedure is aimed at serving the forestry sector in Sabah as a tool to facilitate the changeover from pure exploitation of the forest to sustainable practices.
Timber harvesting was investigated both in terms of commercial timber volume extracted and impact on residual stand. Conventional (CNV) and reduced impact logging (RIL) techniques were compared on the basis of pre- and post-harvesting stand inventories. The timber volume extracted averaged 87 m3 ha−1 and the resulting commercial volume was 46 m3 ha−1 (i.e. 53.7% of the felled volume). On average, logging damage affected 40% of the residual trees (diameter at breast height (dbh) over 10 cm); injured and dead trees were recorded in equivalent proportions (21% and 19%, respectively). Generally, felling operations caused injury to trees, crown damage being most common, whereas skidding caused death to trees, essentially by uprooting. Tree injury and death from RIL in contrast, was substantially lower (30.5%) than from conventional methods (48.1%). This study demonstrated that the impact of logging on trees can be substantially reduced by strict supervision and planning of logging operations and limit of harvesting intensity, which should not exceed 80 m3 ha−1. If these technical recommedations are followed, it is possible to reduce the damage by 20% which is equivalent to about 100 stems ha−1 (dbh over 10 cm).
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