Removal Of Logging Residues Research Articles

Effect of logging residue removal and mechanical site preparation on productivity of the subsequent Scots pine (Pinus sylvestris L.) stands

Key messageRemoval of logging residue negatively affected tree diameter and height, but had no significant effect on the basal area of the subsequent stand (in the mid-term). On the other hand, different methods of mechanical site preparation (bedding, plowing furrows, and trenching) had no effect on tree growth 1 year after planting, but had a significant effect on tree diameter, tree height, and basal area in the mid-term. Bedding treatments could have a significant positive impact on the productivity of the subsequent Scots pine stands, even when planted on sandy, free-draining soils.ContextIncreased use of logging residues in forests may address the growing demand for renewable energy. However, concerns have arisen regarding the depletion of the forest soil, resulting in a decrease in the productivity of the next forest generation. Identifying the drivers of forest growth may be the key to understanding the relationship between logging residue removal and stand productivity.AimsQuantifying the effect of three mechanical site preparation methods (bedding, plowing furrows, and trenching) combined with five methods of logging residue management (complete removal, comminution, incineration, leaving whole, comminution with, and without mixing with topsoil) on growth of subsequent Scots pine stands, 1 year and 12 years after planting.MethodsThe experiment was set up as a randomized complete block design of 45 plots with three replications of combinations of three mechanical site preparation methods and five logging residue treatment methods.ResultsThe effects of the different methods of mechanical site preparation were not significant 1 year after planting but bedding treatment caused increase in DBH, tree height, and basal area after 12 years. Various methods of logging residue management did not cause any differences in the survival rate nor the basal area of the next-generation stands; however, there was a significant influence on tree sizes. Moreover, the effects changed with time; in plots with a complete removal of logging residues, the trees were the highest 1 year after planting, but after 12 years, their height and DBH were the lowest.ConclusionsIt can be concluded that bedding treatments could have a significant positive impact on the productivity of the subsequent Scots pine stands. No effect found of different logging residue treatments on the productivity of Scots pine stands further confirms that the increased removal of biomass from the forest environment does not necessarily result in its rapid degradation. Observations at longer term are however needed to obtain the full spectrum of responses to logging residue removal.

Soil C storage following salvage logging and residue management in bark beetle-infested lodgepole pine forests

Bark beetle outbreaks have altered carbon (C) dynamics in lodgepole pine (Pinus contorta var. latifolia Engelm. ex Wats.) forests across western North America. The sensitivity of soil C to post-beetle management operations remains unknown in these forests. We quantified total C stocks in the O horizon and upper mineral soil (0–10 cm) 6–7 years after salvage logging in lodgepole pine forests of northern Colorado and compared biomass retention or removal residue management to uncut beetle-infested forests. We evaluated the quantity and chemical composition of C in physical fractions of the O horizon and upper mineral soil layers to better understand how management impacts the quality of C with implications for soil C persistence. Post-harvest residue retention increased O horizon C storage compared to the removal treatment and uncut stands. Total soil C (O horizon and upper 0–10 cm mineral soil) was an average of 11.4 (±5.6) Mg C ha−1 higher in salvage logged plots compared to uncut forests and the increase was primarily in particulate organic matter. Salvage logging did not alter the chemical composition of the soil C fractions analyzed. The C:N ratios, Fourier-transform mid-infrared spectra, and 13C values analyses each showed that the C composition of the organic and upper mineral soil layers were distinct. This indicates that physical transfer of fresh or decomposed O horizon material may not be the primary source of particulate C, and we suggest that belowground inputs are likely to be an important contributor to these mineral soils. Our finding that logging residue removal did not reduce post-harvest upper mineral soil C stocks has implications for biomass harvesting in these forests, though the long-term impacts of post-bark beetle management on C storage in these ecosystems depend on understory dynamics, tree regeneration and forest recovery that will progress over the course of decades. This work suggests that greater understanding of post-logging organic matter inputs and C dynamics in O horizon and mineral SOM fractions can help inform forest management aimed at sustaining soil C.

Fungal communities in decomposing wood along an energy wood harvest gradient

The current requirements to decrease the consumption and greenhouse gas emissions of fossil fuels have increased the demand of renewable energy sources. In forestry, this situation has intensified harvesting practices resulting in a decreased amount of woody debris left on the clear-cut areas. Impacts of energy wood harvest on wood-decomposing fungi were studied in a large-scale experiment in clear-cut stands in three geographical areas in Finland. A sequence of treatments was expected to form a forestry induced soil disturbance gradient: (1) logging residues left at site, no soil preparation; (2) logging residues left at site, patch mounding; (3) 70% logging residue removal, patch mounding; and (4) complete stump and logging residue removal, patch mounding. Pre-weighed wood discs were incubated on the intact soil cover for four years to estimate decomposition rate and fungal decomposer community. A soil sample was taken underneath each disc to evaluate the direct inoculation potential of the soil. The main results were as follows: (1) The differences between the treatments were not significant, while the geographical factors affected the decomposition rate and the fungal communities of the wood discs. (2) The fungal composition in the wood discs did not reflect the underlying soil fungal community, which indicates that a part of the fungal species inhabiting wood discs originated from airborne surrounding sources. (3) The increase in fungal species diversity was associated to the wood decay process, indicated by parallel increase in the wood decomposition rate and the number of white rot and mycorrhizal fungi. Thus our study indicates that in addition to local environment, landscape-level factors control the decomposer fungal community and its activity in wood.

Soil microbial functions are affected by organic matter removal in temperate deciduous forest

A growing demand for renewable carbon (C) has led to intensified forest management resulting in the use of forest residues (e.g. canopy, bark or litter layer) as energy sources with potential modifications of soil properties and tree productivity. Because microbes mediate the recycling of C and nutrients sequestered in organic matter, we investigated the effects of organic matter (OM) removal on soil properties, root surfaces, microbial functions and abundance using a new observational forest network. We compared leaf litter and logging residue removal plots to reference plots in six beech forests located in the northern half of France. After three consecutive years of OM removal, C and nitrogen (N) pools were not affected, but OM exportation decreased the cation exchange capacity and available phosphorus (P) pool by respectively 12% and 30% in the topsoil (0–5 cm depth). Fine root surface area significantly increased by 21% in the subsoil (5–10 cm depth) in response to OM removal. Enzymatic activities involved in N and P mobilisation decreased from 12 to 38% with the manipulation of OM. Community-level profiling (CLPP) based on BIOLOG approach revealed that the metabolic potential of the microbial community strongly decreased in response to OM removal. Our results indicated that intensive forestry could affect microbial functions implicated in nutrients mobilisation. We demonstrated that soil organic matter (SOM) content is a predictor of microbial functions resistance to forest residue removal. We recommend that intensive forestry should be reduced or limited in beech forests characterised by low soil OM contents.

Leaf litter decomposition and decomposer communities in streams affected by intensive forest biomass removal

The complexity and multidimensionality of freshwater processes require multiple metrics to assess their responses to disturbances. However, studies have historically relied on structural attributes, while functional attributes have received much less attention. The relative ease of implementing functional attributes, like leaf decomposition assays, make them an attractive choice to complement structural attributes (e.g. species diversity and community composition). However, the congruence of these disparate attributes is still debatable, as studies have reported results to be strongly context-dependent. The concept of using forest biomass as a source of alternative energy instead of fossil fuel has led to rapid changes in forestry practices. One of these practices involves removal of logging residues that would have otherwise been left on site (logging residue removal, LRR), potentially leaving the landscape prone to high erosion, run-off and sedimentation. This study investigated the decomposition rates of alder leaves in sites affected by LRR compared with conventionally logged (CL) and near-natural, non-harvested sites. Our results revealed CL as having the strongest effects, while LRR had an intermediate response, both in terms of decomposition rates (ktotal, kmicrobial and kshredders) and microbial biomass. These results match those for structural attributes reported previously at the same sites, thus providing multiple lines of evidence for the ecosystem-level impacts of forestry activities. Bacterial biomass on decomposing leaves was consistently several orders of magnitude greater than that of fungi in all study streams and treatments. Most previous research on the relative contributions of shredders, fungi and bacteria to leaf decomposition has focused on fast-flowing riffles and more research is needed to clarify their relative roles in other types of running waters, such as the slow-flowing, strongly allochthonous and humic forest streams studied by here. In conclusion, this study points to further need to revise the current practice of forestry activities in light of its negative impact on biodiversity.

How climate change adaptation and mitigation strategies can threaten or enhance the biodiversity of production forests: Insights from Sweden

Anthropogenic climate change is altering the management of production forests. These changes are motivated by the need to adapt to the uncertainties and risks of climate change, and by the need to enlist their carbon storage and sequestration capacity as part of global mitigation efforts. These changes do however raise concerns regarding the potential implications for forest biodiversity. Here we evaluate these concerns by assessing the biodiversity implications of climate change adaptation and mitigation strategies (CCAMS) being implemented in the production forests of Sweden. We do so by identifying biodiversity goals aimed specifically at closing the existing gap between the habitat requirements of forest-dependent species, and the conditions provided by production forests, in terms of tree species composition, forest structures, and spatio-temporal forest patterns. We then use the existing literature to determine whether and by which pathway each CCAMS is likely to bridge or extend this gap. Our results indicate that CCAMS will often come into direct or partial conflict with Swedish biodiversity goals in production forests. Furthermore, some CCAMS which are inconsistent with biodiversity goals, such as logging residue removal, are being implemented more extensively than those which were most consistent with biodiversity goals. We nevertheless challenge the necessity of setting the preservation of forest biodiversity against climate change mitigation and adaptation. We clarify how CCAMS with negative biodiversity implications may still be implemented without adverse outcomes, if coupled with conservation interventions, or combined with other CCAMS deemed complementary in habitat provision.

Soil disturbance and early vegetation response to varying intensity of energy wood harvest

Forest biomass plays an important role in the production of renewable energy, particularly in northern Europe. During recent decades, tree stumps have also been increasingly used for energy production. The environmental impacts of stump removal on the functioning of forest ecosystems, for example on soil processes and biodiversity, are still inadequately understood. To investigate the separate impacts of tree stump and logging residue removal on soil and plant variables, we conducted a large-scale replicated experiment in clear-felled stands in three geographical areas. Four energy wood harvesting levels were combined with patch mounding (organic and mineral soil layer turned upside down) as a site preparation method. The harvesting treatments were: (1) no energy wood harvesting, (2) 70% logging residue removal, (3) 25 stumps per hectare left at site and 70% logging residue removal (maximum level in official recommendations), (4) complete stump and 100% logging residue removal. Soil disturbance in terms of mineral and organic soil cover increased with the increasing harvesting level, but complete stump removal did not increase the mineral soil cover more than partial stump removal (on average 95% removed). Despite the increase in soil disturbance, stump removal did not have an overall impact on plant species richness or vegetation composition in the second growing season after harvesting. However, an increasing trend in Betula spp. biomass with increasing harvesting intensity was seen in two of three study areas in four years. Our results underscored the high site-dependency of the effects of stump removal on ecological variables, thus the initial stand structure and vegetation type need to be considered when planning harvesting treatments.

Bioenergy vs biodiversity: effects of intensive forest biomass removal on stream and riparian communities

The removal of forest logging residues for bioenergy production is projected to increase by several orders of magnitudes in the near future. Little is known about the environmental consequences of this practice, however, especially in freshwater ecosystems. Using data from 18 headwater streams in central Finland, we assessed the responses of four lotic (diatoms, bryophytes, dipterans and benthic macroinvertebrates) and two riparian (bryophytes and vascular plants) organism groups to logging residue removal (LRR). The streams were divided in three groups: unharvested, conventional logging (no LRR) or LRR (both conventional logging and LRR). We hypothesized that conventional logging would result in intermediate biodiversity and environmental responses, with LRR showing the strongest effects. Contrary to our expectation, conventional logging elicited the strongest responses, whereas LRR had little additional impact when compared with conventional logging. This likely reflects a stricter adherence by the LRR operators to forest management guidelines. Our approach of comparing both conventional logging and LRR to unharvested sites yielded important insights that would have been missed otherwise. Rigorous monitoring using multiple taxonomic groups of both terrestrial and freshwater origin is needed to detect the long-term effects of LRR activities.

Domestic heating from forest logging residues: environmental risks and benefits

The European Union (EU) relies largely on bioenergy to achieve its climate and energy targets for 2020 and beyond. Special focus is placed on utilization of biomass residues, which are considered to cause low environmental impacts.We used the dataset from the latest European Commission document on the sustainability of solid and gaseous biomass (SWD2014 259), complementing those results by: i) designing three pathways for domestic-heat production using forest logging residues, with different combustion technologies; ii) expanding the analysis to include forest carbon stock development with and without bioenergy; iii) using absolute climate metrics to assess the surface temperature response by the end of the century to a bioenergy and a reference fossil system; iv) including multiple climate forcers (well-mixed GHG, near term climate forcers and surface albedo change); iv) quantifying life cycle impacts on acidification, particulate matter emissions and photochemical ozone formation; v) reviewing potential risks for forest ecosystem degradation due to increased removal of residues.Supply-chain GHG savings of the three pathways analysed ranged between 80% and 96% compared to a natural gas system, above the 70% threshold suggested by the EU. However, the climate impact of bioenergy should be assessed by considering also the non-bioenergy uses of the biomass and by including all climate forcers.We calculate the Surface Temperature Response to bioenergy and fossil systems by means of Absolute Global surface Temperature Potential (AGTP) metric. Domestic heating from logging residues is generally beneficial to mitigate the surface temperature increase by 2100 compared to the use of natural gas and other fossil sources. As long as residues with a decay rate in the forest higher than 2.7%*yr−1 are considered as feedstock, investing now in the mobilization of residues for heat production can reduce the temperature increase by 2100 compared to all the fossil sources analysed, both in case of bioenergy as a systemic change or in case of bioenergy as a transitory option.Furthermore, several environmental risks are associated with the removal and use of forest logging residues for bioenergy. These issues concern mostly local air pollution, biodiversity loss and, mainly for stumps removal, physical damage to forest soils.Forest logging residues are not free of environmental risks. Actions promoting their use should consider: (i) that climate change mitigation depends mainly on the decay rate of biomass under natural decomposition and time and rate of technology deployment, (ii) whether management guidelines aimed at protecting long-term forest productivity are in place and (iii) whether proper actions for the management of adverse effects on local air pollution are in place.

Logging residue harvest may decrease enzymatic activity of boreal forest soils

Nowadays conventional stem-only harvest where logging residues are left on the site is often displaced by whole-tree harvest, in which logging residues are harvested for use as bioenergy. Logging residues consist of tree branches and tops of stems with needles. The aim of this study was to evaluate the effect of logging residue harvest on soil enzyme activities involved in C, N and P cycling, namely β-glucosidase, β-glucosaminidase, protease and acid phosphatase in relation to other soil characteristics (i.e. soil respiration, net N mineralization, microbial biomass C and N). Soil samples were taken from the humus layer of five study sites, differing in fertility, dominating tree species and time elapsed after treatment. The study sites were Norway spruce (Picea abies, (L.) Karst) and Scots pine (Pinus sylvestris L.) stands in different parts of Finland. Four of the study sites were single-tree experiments, where thinning was performed 4–5 years before this study and 3–4 different doses of logging residues (from 0 up to 37.5 Mg ha−1) were distributed on a circle around a single tree in 3 replicates. The last field experiment had been thinned twice, 23 and 13 years ago; the treatments in 3 replicates were whole-tree harvest and stem-only harvest. In the whole-tree harvest vs. stem-only harvest experiment, activities of β-glucosidase, β-glucosaminidase, acid phosphatase were similar in both treatments. In general, in the single-tree experiment with pine, enzymes raised the activity in response to increasing amount of logging residue. The pattern was less clear for the spruce single-tree experiment, but acid phosphatase and protease activities increased with the increase in amount of logging residue. In general, other soil characteristics were less affected than enzyme activities by logging residue removal; however, in some sites logging residues seemed to increase net C and N mineralization with increasing logging residue amount. Our results suggest that retaining logging residues on the site can increase soil enzyme activities and C and N mineralization.

Short-term impacts of energy wood harvesting on ectomycorrhizal fungal communities of Norway spruce saplings.

The increased demand for harvesting energy wood raises questions about its effects on the functioning of the forest ecosystems, soil processes and biodiversity. Impacts of tree stump removal on ectomycorrhizal fungal (EMF) communities of Norway spruce saplings were studied with 454-pyrosequencing in a 3-year field experiment replicated in 3 geographical areas. This is possibly the most thorough investigation of EMF communities associated with saplings grown on sites subjected to energy wood harvesting. To separate impacts of tree stump and logging residue removal on EMF and plant variables, we used three harvesting treatments with increasing complexity from patch mounding alone (P) to patch mounding combined with logging residue removal (RP), and patch mounding combined with both logging residue and stump removal (SRP). Saplings grown in uncut forests (F) served as references for harvesting treatments. A majority of sequences (>92%) and operational taxonomic units (OTUs, 55%) were assigned as EMF. EMF OTU richness, fungal community composition or sapling growth did not differ between harvesting treatments (P, RP and SRP), while EMF OTU richness, diversity and evenness were highest and sapling growth lowest in the undisturbed reference forests (F). The short study period may partially explain the similarities in fungal and sapling variables in different harvesting treatments. In conclusion, our results indicate that neither stump removal nor logging residue removal have significant additional negative impacts on EMF communities or growth of Norway spruce saplings in the short-term compared with the impacts of more conventional harvesting methods, including clear cutting and patch mounding.

The impact of logging residue on soil GHG fluxes in a drained peatland forest

Northern peatlands contain substantial reservoirs of carbon (C). Forestry activities endanger the C storages in some of these areas. While the initial impacts of forestry drainage on peatland greenhouse gas (GHG) balance have been studied, the impacts of other silvicultural practices, e.g. logging residue (LR) retention or removal, are not known. We measured the CH4, N2O and CO2 fluxes between peat soil and atmosphere with and without decomposing LR over three (2002–2004) seasons (May–Oct) following clearfelling in a drained peatland forest, along with the mass loss of LR. Seasonal average CO2 efflux from plots with LR (3070g CO2 m−2 season−1) was twice as high as that from plots without LR (1447g CO2 m−2 season−1). Less than 40% of this difference was accounted for by the decay of logging residues (530g CO2 m−2 season−1), so the majority of the increased CO2 efflux was caused by increased soil organic matter decomposition under the LR. Furthermore LR increased soil N2O fluxes over 3-fold (0.70g N2O m−2 season−1), compared to plots without LR (0.19g N2O m−2 season−1), while no change in CH4 emissions was observed. Our results indicate that LR retention in clearfelled peatland sites may significantly increase GHG emissions and C release from the soil organic matter C storage. This would make the harvesting of LR for biofuel more beneficial, in the form of avoided emissions. Further investigations of the sources of CO2 under logging residues are, however, needed to confirm this finding.

Logging residue removal after thinning in Nordic boreal forests: Long-term impact on tree growth

The aim of this study was to determine the effect of whole-tree harvesting (WTH) on the growth of Scots pine ( Pinus sylvestris L.) and Norway spruce ( Picea abies (L.) Karst.) as compared to conventional stem harvesting (CH) over 10 and 20 years. Compensatory (WTH + CoF) and normal nitrogen-based (CH + F or WTH + F) fertilisation were also studied. A series of 22 field experiments were established during 1977–1987, representing a range of site types and climatic conditions in Finland, Norway and Sweden. The treatments were performed at the time of establishment and were repeated after 10–13 years at 11 experimental sites. Seven experiments were followed for 25 years. Volume increment was on average significantly lower after WTH than after CH in both 10-year periods in the spruce stands. In the pine stands thinned only once, the WTH induced growth reduction was significant during the second 10-year period, indicating a long-term response. Volume increment of pine stands was 4 and 8% and that of spruce stands 5 and 13% lower on the WTH plots than on CH during the first and the second 10-year period, respectively. For the second 10-year period the relative volume increment of the whole-tree harvested plots tended to be negatively correlated with the amount of logging residue. Accordingly, the relative volume increment decreased more, the more logging residue was harvested, stressing the importance of developing methods for leaving the nutrient-rich needles on site. If nutrient (N, P, K) losses with the removed logging residues were compensated with fertiliser (WTH + CoF), the volume increment was equal to that in the CH plots. Nitrogen (150–180 kg ha −1) or N + P fertilisation increased tree growth in all experiments except in one very productive spruce stand. Pine stands fertilised only once had a normal positive growth response during the first 10-year period, on average 13 m 3 ha −1, followed by a negative response of 5 m 3 ha −1 during the second 10-year period. The fertilisation effect of WTH + F and WTH + CoF on basal area increment was both smaller and shorter than with CH + F.

The long-term effects of logging residue removal on forest floor nutrient capital, foliar chemistry and growth of a Norway spruce stand

This study compared the nutrient capital of the forest floor, the nutrient status of trees, and the growth of a stand of Norway spruce (Picea abies L. (Karst.)) planted on a whole-tree harvesting treatment (needles left on site) with a conventional stem-only harvesting treatment 30 years after clearcutting. No significant treatment effects were detected in the amount of organic matter, the amounts of nutrients in the forest floor, or the concentrations of foliar nutrients. The results indicate that whole-tree harvesting with the needles left on the site did not reduce the long-term nutrient capital of the forest floor or the nutritional status of trees. Whole-tree harvesting significantly reduced the height of dominant spruce compared to stem-only harvesting, however the stem volume of dominant spruce did not differ between the harvesting treatments. The greater height growth of the dominant trees in the stem-only harvesting treatment could be attributed to indirect factors other than changes in site resource availability (e.g. protection against frost damage), and hence the effect of whole-tree harvesting on potential site productivity was inconclusive due to the confounding effect of site factors. In the whole-tree harvesting treatment, the total stem volume of the stand and, consequently, the actual site productivity, was lower when compared to stem-only harvesting due to the lower density of naturally regenerated seedlings.

Whole-tree harvesting at clear-felling: Impact on soil chemistry, needle nutrient concentrations and growth of Scots pine

The effects of logging residue removal on soil chemical properties and the needle nutrient concentrations and growth of Scots pine (Pinus sylvestris L.) were studied after clear-felling on two sites of different fertility in eastern Finland. Harvesting was carried out either conventionally, i.e. harvesting only the stems [conventional harvesting (CH)], or totally, i.e. harvesting all of the above-ground tree biomass [whole-tree harvesting (WTH)]. The seedlings were planted in ploughing tilts on 50×50 m sample plots. The number of replications was 24 on the more fertile site and 12 on the less fertile site. Compared with CH, WTH had no effects on either the survival or growth of Scots pine trees during the first 22 years. Apart from the statistically significant increase in needle nitrogen concentration in the WTH treatment on the less fertile site, the needle concentrations were not affected by the harvesting intensity. On the more fertile site, the total amounts of carbon, nitrogen and calcium, as well as exchangeable calcium and extractable phosphorus in the organic layer, were significantly lower on the WTH than on the CH plots. Although the pH remained unchanged, the exchangeable aluminium concentrations increased on the more fertile site, and on both sites the calcium/aluminium ratio was significantly lower on the WTH plots than on the CH plots.

Logging residue removal after thinning in boreal forests: long-term impact on the nutrient status of Norway spruce and Scots pine needles

The aim of this study was to compare how conventional stem harvesting (CH) and whole-tree harvesting (WTH) in the first, and in some cases also in the second, thinning affect the needle nutrient status of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) stands in Finland. A series of 12 long-term field experiments was studied. The experiments were established during 1978-86. The effects of logging residue removal after thinnings on the needle nutrient concentrations were generally minor and without any overall trends, but there were differences between experiments. Trees tend to maintain their current needle nutrient concentrations at the same level by re-utilizing the nutrients stored in the older tissues and by changing C allocation in the whole tree. Thus, needle analysis should be combined with stem growth data in order to achieve a more comprehensive understanding of the effects of WTH on the nutrient status of trees.

Effects of logging residue removal on ground-active beetles in temperate forests

Logging residue (“slash”) left on clear-cuttings may affect the microhabitat complexity, and thereby indirectly the beetle (Coleoptera) populations. In three regions (West, North and East) of south and central Sweden, we studied short-term effects of slash removal on species richness and abundance of beetles, collected by pitfall trapping in 16 clear-cuttings (<1 year old) in coniferous and mixed forests. The sites were managed in two alternative ways, either slash was removed (SR), or slash was left (SL). Overall, the number of morphospecies per trap was significantly higher on SL sites than on SR sites. Species richness differed significantly between the regions, the Western region being the poorest in number of species per trap. Rarefaction plots of species richness in four sites suggested that accumulation rate of species differed between two SR sites but rates were similar for two SL sites. Microhabitat structure was measured by aboveground height of slash heaps. Slash height was positively correlated with the number of sticks in slash heap and fractal dimension, respectively. There was a positive relationship between the number of individuals per trap and slash height in SR sites in the Western and Eastern regions, but not in the Northern one. We concluded that extensive slash removal leads to impoverish species richness of Coleoptera at a local scale. Slash heaps left on site may provide important refuges for ground-active beetles. Moreover, our results supported the general theory that microhabitat structure affects arthropod abundance and diversity.