Current Forest Management Research Articles

Strategic change in the forest industry towards the biorefining business

Abstract The aim of the study was to explore the current forest industry's change features, necessary resources and management for the biorefining business in Scandinavia and North America. A total of 23 representatives from the forest, bioenergy and bioproducts sectors participated in themed interviews in the last round of a three-phase Delphi study. In both Scandinavian and North American forest industries, a conservative organizational culture and lack of financial resources create barriers to change. The role of the forest industry in the forest biorefinery consortium is largely seen to be that of a biomass provider. The scope of change depends on context-specific features, such as biorefinery location and raw material availability. Operating a commercial-scale biorefinery facility requires both new managerial and operational-level skills. Readiness for change needs to be embedded in the organizational culture — and the key to attaining this is open-minded organizational management. It is believed that there are innovative personnel in forest industry companies, yet the current culture does not encourage such people to submit their ideas. Success in the biorefinery business cannot be achieved without collaboration. However, sharing of profits among partners in the consortium will be challenging.

Old Trees: Extraction, Conservation Can Coexist

Because large old trees are essential for forest ecosystem integrity and biodiversity, timber extraction in managed forests should preferentially be concentrated where large old trees are least likely to develop (Global decline in large old trees, D. B. Lindenmayer et al. , Perspectives, 7 December 2012, p. [1305][1]). However, timber extraction and the conservation of large old trees are not necessarily mutually exclusive. Current forest policy and management practices in Flanders, Belgium, aim to convert even-aged stands (areas in which trees are all the same age) to stands with trees of varying ages in an effort to increase forest ecosystem stability and resilience and to allow trees to grow old. As part of their ecologically sustainable forest management, public forest managers have adopted a large-tree retention approach [see also ([ 1 ][2], [ 2 ][3])]. Tree islands within stands managed for production of high-quality timber are reserved for conservation, and trees within these islands will never be extracted. Large old trees of commercially valuable species that have grown beyond the commercially optimal dimensions will not be logged either. And no tree beyond a threshold diameter [currently set at dbh (diameter at breast height) of more than 102 cm] will ever be logged. The strip-shelterwood system (in which trees are cut in linear strips and surrounding trees are given time to grow old) and the coppice-with-standards system (in which some trees are left to grow while others around them are cut) are two examples of forest management that allows the combination of sustainable forest exploitation and conservation of large old trees. ![Figure][4] CREDIT: GRZEGORZ MIKUSINSKI 1. [↵][5] 1. D. B. Lindenmayer, 2. W. F. Laurance , Biol. Conserv. 151, 11 (2012). [OpenUrl][6][CrossRef][7][Web of Science][8] 2. [↵][9] 1. D. B. Lindenmayer 2. et al ., Conserv. Lett. 5, 421 (2012). [OpenUrl][10][CrossRef][11] [1]: /lookup/doi/10.1126/science.1231070 [2]: #ref-1 [3]: #ref-2 [4]: pending:yes [5]: #xref-ref-1-1 View reference 1 in text [6]: {openurl}?query=rft.jtitle%253DBiol.%2BConserv.%26rft.volume%253D151%26rft.spage%253D11%26rft_id%253Dinfo%253Adoi%252F10.1016%252Fj.biocon.2011.10.032%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [7]: /lookup/external-ref?access_num=10.1016/j.biocon.2011.10.032&link_type=DOI [8]: /lookup/external-ref?access_num=000306042600004&link_type=ISI [9]: #xref-ref-2-1 View reference 2 in text [10]: {openurl}?query=rft.jtitle%253DConserv.%2BLett.%26rft.volume%253D5%26rft.spage%253D421%26rft_id%253Dinfo%253Adoi%252F10.1111%252Fj.1755-263X.2012.00257.x%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [11]: /lookup/external-ref?access_num=10.1111/j.1755-263X.2012.00257.x&link_type=DOI

Modeling the Long-Term Impacts of Logging on Genetic Diversity and Demography of Hymenaea courbaril

Although selective logging is a common practice for timber production in the Brazilian Amazon, very little is known about its impacts on genetic diversity and demography of the harvested species. This study explores the sustainability of current forest management systems in the BrazilianAmazon by modeling harvesting cycles and examining the impacts on the genetic diversity and demography of the highly valued speciesHymenaea courbaril. Using extensive field data, we introduced a two-step modeling procedure for EcoGene software that allowed us to identify optimal fellingcycles that were later used for testing and defining sustainable logging parameters. The results show that logging cycles forH. courbaril should be approximately of 110 years, as opposed to the 30-year cycle currently used in Brazil, and harvesting levels should consider a combinationof larger minimum cutting diameters (75-100 cm) and lower logging intensities (10-50%). We conclude that current practices in Brazil (30-year cycle, logging intensities of 90%, and minimum cutting diameters of 50 cm) are unsustainable forH. courbaril and that the currentpractice of using general logging prescriptions for all species does not deliver sustainable forest management in the Amazon. Brazilian forest harvesting regulations need to move toward species-specific prescriptions to ensure real sustainability in the long term.

Forest stand height determination from low point density airborne laser scanning data in Roznava Forest enterprise zone (Slovakia)

Abstract: The presented paper discusses the potential of low point density airborne laser scanning (ALS) data for use in forestry management. Scanning was carried out in the Rožnava Forest enterprise zone, Slovakia, with a mean laser point density of 1 point per 3 m2. Data were processed in SCOP++ using the hierarchic robust filtering technique. Two DTMs were created from airborne laser scanning (ALS) and contour data and one DSM was created using ALS data. For forest stand height, two normalised DSMs (nDSMs) were created by subtraction of the DSM and DTM. The forest stand heights derived from these nDSMs and the application of maximum and mean zonal functions were compared with those contained in the current Forest Management Plan (FMP). The forest stand heights derived from these data and the application of maxima and mean zonal functions were compared with those contained in the current Forest management plan. The use of the mean function and the contour-derived DTM resulted in forest stand height being underestimated by approximately 3% for stands of densities 0.9 and 1.0, and overestimated by 6% for a stand density of 0.8. Overestimation was significantly greater for lower forest stand densities: 81% for a stand density of 0.0 and 37% for a density of 0.4, with other discrepancies ranging between 15 and 30%. Although low point density ALS should be used carefully in the determination of other forest stand parameters, this low-cost method makes it useful as a control tool for felling, measurement of disaster areas and the detection of gross errors in the FMP data. Through determination of forest stand height, tree felling in three forest stands was identified. Because of big differences between the determined forest stand height and the heights obtained from the FMP, tree felling was verified on orthoimages.

Linking forest management, policy and biodiversity indicators – A comparison of Lithuania and Southern Sweden

Lithuania and Southern Sweden share similar natural conditions, but differ considerably in forest policies and management; thereby providing an opportune basis for comparative studies. Since the 1990s, Sweden has attempted to reduce the negative impact of its forest management on biodiversity, after decades of intensive production forestry. In contrast, Lithuania has been intensifying forestry practices associated with the post-soviet socio-economic transition. Here we assess the actual outcomes by comparing selected forest structure and composition variables known to be indicators for forest biodiversity; and estimate the prospective trends by scrutinising current forest policies and management.Our results indicate that Lithuanian forests consistently possessed higher rankings in six indices related to tree species composition, stand age, and deadwood quantities that are positively associated with forest biodiversity. The reverse is indicated by those data on stand age and tree diameter that are associated with centennial dynamics in forest utilisation intensity. With respect to policy instruments, Lithuania designates a substantially greater share of forest area to non-timber functions and legislates more severe management restrictions in forests targeting timber production. Concurrently, all estimates of forestry activities indicate more intensive forest management in Southern Sweden, including a higher share of artificial regeneration and shorter rotations. This allows concluding that, if current forest management practices persist, then an increased “biodiversity gap” may be expected between the two countries. The study concludes with discussing to what degree the identified trends are the direct product of targeted policies versus merely by-products of other factors.

庐山森林景观格局变化的长期动态模拟

Forest succession is a naturally occurring process of reorganization which occurs constantly in forest ecosystems; the term refers to the process of one plant community being replaced by another over time. The process of forest vegetation ecological succession is driven by underlying natural conditions and anthropogenic disturbance. We can infer dynamic changes of landscape patterns and corresponding ecological processes of forest succession using forest landscape dynamic analysis based on vegetation patterns. Research related to vegetational succession provides a foundation for the understanding of dynamic changes of forest landscape patterns. The changes of forest landscape pattern also influence nutrient cycling and energy flows in forest ecosystems while restricting a variety of ecological processes. As a result,the study on forest landscape patterns explains very important dynamic processes of forest succession.The natural laboratory of Mount Lushan provides a unique site for studying ecological succession as it relates to vegetation and restoration ecology. The study of forest succession is the foundation of recovery and restoration activities. This type of research depends on the study of ecological succession of vegetation which can provide a basis for understanding the dynamics of landscape change. Using the spatially explicit landscape simulation model( LANDIS),this paper analyzes forest vegetation on Mount Lushan,by stimulating the dynamics of the vegetation's ecological succession in the next 300 aunder undisturbed natural conditions,and determines the representative landscape pattern indices of each patch. This process includes measures of the proportion of the landscape covered by each type of patch area as well as determining the values for the aggregation,fractal dimension,diversity and evenness indices. This process allows the analysis of the spatial distribution pattern of dominant tree species,which helps reveal the factors regulating vegetation succession and helps predict the future trends in variation of the forest landscape. Finally,the theoretical basis for successfully realizing sustainable development of forest resources is discussed. The results indicate:( 1) Over the next 300 a,the extent of a stable populations of broad-leaved tree species will tend to increase; ecological succession in the entire Mount Lushan forest ecosystem is moving in the direction of the reformation of a complex zonal evergreen broad-leaved forest system.( 2) The aggregation index for broad-leaved tree species exhibits a pattern of slow growth in the next 150 a,and then stabilizes after 150 a. The aggregation index of fir remained steady for the entire 300 a while the degree of aggregation for moso bamboo declined steadily throughout the entire simulation until it stabilized during the end stage of the simulation.( 3) The fractal dimension of all dominant tree species is between 1 and 1. 1,illustrating that the edge of each patch is relatively inerratic and experiences small changes during natural forest vegetation succession.( 4) The diversity index of the research region initially tended to increase and later maintained a slow rate of decline. Also,the evenness index initially declined,then rose and went into a slow decline at the end of the simulation. The results of the simulation indicate that the Mount Lushan ecosystem is trending toward an optimal climax community based on the natural forces of ecological succession occurring in the forest community. During this natural ecological succession,various species predominate before the climate evergreen broad-leaved forest stage becomes dominant. In the next 300 years,the reforestation program implemented in the 1960s will not have an obvious influence on climax forest landscape patterns in Mount Lushan. Our research provides a scientific foundation for current and future forest landscape management practices on Mount Lushan. In the long run,we should continue to implement a strict policy of protecting hillside forest habitat to facilitate ongoing afforestation efforts.

Storm damage of Douglas-fir unexpectedly high compared to Norway spruce

Since storm damage has a large impact on forest management in Central Europe, we investigated the main storm risk factors for two important conifer species, Douglas-fir (Pseudotsuga menziesii [Mirbel] Franco) and Norway spruce (Picea abies [L.] Karst.). We compared general storm damage levels of Douglas-fir and Norway spruce, the latter being known to have high storm risk among European tree species. Generalized linear mixed models and boosted regression trees were applied to recorded storm damage of individual trees from long-term experimental plots in southwest Germany. This included two major winter storm events in 1990 and 1999. Over 40 candidate predictors were tested for their explanatory power for storm damage and summarized into predictor categories for further interpretation. The two most important categories associated with storm damage were timber removals and topographic or site information, explaining between 18 and 54 % of storm damage risk, respectively. Remarkably, general damage levels were not different between Douglas-fir and Norway spruce. Under current forest management approaches, Douglas-fir may be considered a species with high storm risk in Central Europe, comparable to that of Norway spruce.

Forest protection and forest harvest as strategies for ecological sustainability and climate change mitigation

An important consideration in forest management to mitigate climate change is the balance between forest carbon (C) storage and ecological sustainability. We explore the effects of management strategies on tradeoffs between forest C stocks and ecological sustainability under five scenarios, three of which included management and two scenarios which provide baselines emulating the natural forest. Managed forest scenarios were: (a) Protection (PROT), i.e., management by suppression of natural disturbance and harvest exclusion; (b) Harvest at a higher rate removing all sustainably available wood (HHARV); (c) Harvest at the lower historical average rate of harvest, AHARV. Both harvest scenarios reflected current forest management practices in the study area, including suppression of natural disturbance and a large (>20% of total) forest area reserved from harvest. Scenarios (d) and (e) simulated “natural” forest with unsuppressed fire at higher (NDH) or lower (NDL) levels and no harvest. Ecological sustainability was evaluated using a coarse filter approach where forest age class and tree species composition were indicators of condition. The study area encompassed 3.4 million hectares of forest in northeastern Ontario at the interface between the temperate hardwood and boreal forest zones. Future forest condition for each scenario was modeled using a timber supply model (SFMM), and C stored in forests and wood products were estimated using the FORCARB-ON model. Forest protection (PROT) resulted in greatest forest C stocks, especially in the near term, but was within 95% of its maximum, becoming saturated within 30years. Harvesting (HHARV and AHARV) resulted in less forest C stock compared to PROT, however, after 100years of adding C in wood products to that in regenerating forests total C storage was equivalent or greater than forest C with PROT. In contrast, removing management (NDH and NDL) decreased C relative to any of the management regimes, though in NDL the decrease was delayed for 30years compared to HHARV. Forest sustainability measured by similarity to natural forest age class was superior with HHARV and AHARV compared to PROT, although no management regime produced a fully natural result. PROT in particular largely lacked younger age classes. All management regimes produced species composition that was near or within the range of natural variation. This analysis provides an example of the types of tradeoffs that can be considered in evaluating the contribution of forests to climate change mitigation, either in a commercial forestry context or in an approach based on protected areas.

Intraspecific variation in climate response of Norway spruce in the eastern Alpine range: Selecting appropriate provenances for future climate

Enhancing adaptation of forest ecosystems to prospective climate change is a major challenge in current forest management. Beyond potential negative effects of climate change such as decreasing productivity due to an increasing number of drought periods and damages from intensified disturbance regimes, there is also a potential for increasing productivity due to prolonged vegetation periods and higher photosynthetic rates. Quantitative genetic variation is crucial for adaptability of species towards environmental changes. The use of suitable reproductive material for forest regeneration will be a key factor essential for both, mitigating negative effects and making the most of potential positive effects. Therefore, insights into intraspecific variation within and among tree populations in climate response are of paramount importance.In our study we investigated intraspecific variation in climate response among Norway spruce (Picea abies) populations in the eastern Alpine range. Results from a comprehensive Austrian provenance test, comprising tree heights at age 15 from 379 populations planted at 29 test sites across Austria, were used to calibrate climate response functions for groups of Norway spruce populations. Potential future changes in productivity for climate change conditions as represented by a regionalized A1B scenario were estimated using height at age 15 as a productivity proxy. Climate response functions were calculated for single populations and aggregated clusters of populations from climatically similar origins.Our results hardly revealed any declines in employed proxies for productivity of Norway spruce throughout its current distribution range in Austria. For most parts of Austria an increase of tree heights up to 45 percent can be expected until 2080. However, the impact of a warming climate is different for individual population groups. Generally, variation in climate response increases with higher temperatures and less precipitation. Thus, an optimized choice of seed material according to prospective future climate conditions has the potential for an additional increase of productivity up to 11 percent.In general, populations from currently warm and drought prone areas seem to be well adapted to respective climate conditions and may be appropriate candidates for extended utilization in future. Furthermore, populations showing the best productivity indices originate from regions, which are phylogenetically distinct from the core distribution area of Norway spruce, suggesting that population history might explain part of the variation in climate response among populations.

Developing criteria and indicators for evaluating sustainable forest management: A case study in Kyrgyzstan

The management of the walnut-fruit forests is one of the key issues in the forestry sector of Kyrgyzstan as it has to address the challenges related to the conservation of forest resources, socio-economic efficiency and the livelihoods of people. The demand for an assessment of the current forest management, which generally involves criteria and indicators (C&I) at all levels, from local to national has increased in the last decade. Therefore a case study has been done, applying a combination of a top-down and bottom-up approach with multi-criteria analysis (MCA) to identify a set of C&I with different groups of stakeholders in selected sites at the forestry management unit level (leshoz). Six workshops and a series of discussion meetings were conducted to perform a sound analysis of the preferences of four different stakeholder groups. A final set of C&I that consists of seven criteria and 45 indicators has been identified for evaluating sustainable forest management (SFM) in the walnut-fruit forests. Forest health and vitality was found to be the most important criterion, while the maintenance of forest biodiversity was found to be the least prioritized among other criteria. Furthermore, four different management strategies were developed by foresters, research groups, ecologists and forest administrators in order to overcome the present challenges in forest management. By utilizing the Analytic Hierarchy Process (AHP), one particular management strategy (MS II) was identified by all stakeholder groups as being the overall best alternative strategy. It was shown that the consideration of non-timber forest products and other options for income generation can improve the livelihood of the people, increase the productivity of resources as well as conserving the gene pool for maintaining forest biodiversity. The findings of this study highlight the importance of a C&I evaluation and its further policy implications. Moreover, it is discussed how the involvement of local stakeholders in the decision making process and their participation in forest management could be stimulated by the C&I development process in the walnut forests of Kyrgyzstan.

模拟分类经营对小兴安岭林区森林生物量的影响

运用空间直观景观模型LANDIS 7.0 PRO,模拟了在当前采伐模式和无采伐两个预案下,小兴安岭林区森林生物量及主要树种生物量在2000-2200年间的动态。模拟结果如下:(1)无采伐预案下,森林生物量由最初的93.6 t/hm²逐渐升高,90a后达到最大值258 t/hm²,之后森林生物量在245 t/hm²上下小幅波动;(2)前100a采伐预案会明显降低森林生物量,与无采伐预案相比森林生物量最大可降低21.4 t/hm²,平均减少14.7 t/hm²;后100a采伐对森林生物量的影响逐渐减弱,森林生物量平均减少2.6 t/hm²;(3)当前采伐模式促进保护树种红松和紫椴生长,其生物量分别最大可提高9.0 t/hm²和0.53 t/hm²,占到无采伐预案生物量的56%和15%;(4)采伐预案对云冷杉生物量影响较小,主要降低先锋树种(白桦、山杨)和一些阔叶树种(枫桦、春榆)的生物量。研究结果表明现行采伐模式在未来100 a内会显著影响森林生物量,之后其影响逐渐减小,并且保护政策能提高所保护树种(红松、紫椴)的生物量,但要保持较高的总生物量,仍需要降低目前的采伐强度。;Forest biomass is the largest carbon pool among terrestrial ecosystems, which plays an important role in mitigating global climate change through sequestrating carbon dioxide and increasing forested area and biomass. However, the disturbances such as climate change, timber harvesting and fire would affect forest biomass, therefore recently, an increasing attention rises on research of a wide range of disturbances that alter forest biomass and species composition. The forested area of China undergone intensive over-logging until 1998, to recover the forest structure and biomass from the past over-logged state, the government implemented forestry classified management. To reveal the effects of the forest management strategy, especially the timber harvesting on the forest and species biomass, the forest and main tree species biomass were simulated by LANDIS 7.0 PRO in the Xiao Xing' an Mountains in northeastern China, which is one of the three largest forested areas in China and the ecotone between temperate and boreal forest. LANDIS 7.0 PRO is the latest version of LANDIS (a spatially explicit model of forest landscape disturbance, management, and succession), which could simulate the dynamics of forest biomass at landscape scale. The study area covers 1.476×10⁵hm²of forested landscape, and its forest dynamic and biomass were simulated over 200 years with the current forest management and no-harvesting scenarios. The main results show that:(1) The forest biomass in the no-harvesting scenario would increase with the simulation years from 93.6 t/hm², and reach a maximum 258 t/hm² approximately at next 90 year, and then fluctuate with an average 245 t/hm², and the potential biomass for this region is about 258 t/hm²; (2) In next 100 years, with the comparison of no-harvesting scenario, the current harvesting scenario significantly decreases the forest biomass, and the maximum and mean forest biomass decline by 21.4 t/hm²and 14.7 t/hm², respectively. But after the next 100 years, current harvesting does not significantly decrease the forest biomass, anyhow the forest biomass trend to decreasing by 2.6 t/hm² averagely; (3) The current harvesting scenario increases the percentages of Korean pine and Amur linden, their biomass increases by 9.0 t/hm²(56%) and 0.53 t/hm²(15%), respectively under the comparison of no-harvesting scenario; (4) The current harvesting scenario affects highly the biomass of deciduous trees including ribbed birch, Black elm, white birch and wild poplar than the coniferous species including the spruces and Kingan fir which are allowed to be logged; (5)The forestry classified management can maintain the original forest structure like species composition, and promote the protected tree species growth and biomass. In addition, our results would be a good evaluation of current forest management strategy and a valuable guide for establishing a new forest management strategy in future.

Habitat Use of Woodpeckers in the Big Woods of Eastern Arkansas

AbstractThe Big Woods of eastern Arkansas contain some of the highest densities of woodpeckers recorded within bottomland hardwood forests of the southeastern United States. A better understanding of habitat use patterns by these woodpeckers is a priority for conservationists seeking to maintain these high densities in the Big Woods and the Lower Mississippi Alluvial Valley as a whole. Hence, we used linear mixed-effects and linear models to estimate the importance of habitat characteristics to woodpecker density in the Big Woods during the breeding seasons of 2006 and 2007 and the winter of 2007. Northern flicker Colaptes auratus density was negatively related to tree density both for moderate (>25 cm diameter at breast height) and larger trees (>61 cm diameter at breast height). Red-headed woodpeckers Melanerpes erythrocephalus also had a negative relationship with density of large (>61 cm diameter at breast height) trees. Bark disfiguration (an index of tree health) was negatively related to red-bellied woodpecker Melanerpes carolinus and yellow-bellied sapsucker Sphyrapicus varius densities. No measured habitat variables explained pileated woodpecker Dryocopus pileatus density. Overall, the high densities of woodpeckers observed in our study suggest that the current forest management of the Big Woods of Arkansas is meeting the nesting, roosting, and foraging requirements for these birds.

Den use, home range and territoriality of the koomal (Trichosurus vulpecula hypoleucus) with implications for current forest management strategies

The koomal (Trichosurus vulpecula hypoleucus) is a declining subspecies (‘near-threatened’), residing largely within the Western Australian jarrah forest, a forest managed for both conservation and for forestry (roughly half is available for logging). Information on the spatial dynamics of koomal is essential to evaluating whether logging prescriptions provide adequate protection for this threatened species. Here we describe the home range and territoriality of koomal, as well as the characteristics and use of their den trees, at multiple sites within the jarrah forest. We also compare the characteristics of den trees used by koomal against logging prescriptions and previous models that estimate availability of den trees. Results suggested that koomal home ranges varied between sites and sexes, with males having the larger home ranges. Koomal also maintained exclusive core territories, probably to protect their den trees from same-sex individuals. Den trees used by koomal had similar characteristics to those outlined in logging prescriptions, but also included two additional characteristics that may improve the retention of trees suitable for koomal: den trees were preferentially of marri (Corymbia calophylla) and wandoo (Eucalyptus wandoo) species, and had some level of canopy connectivity. Overall, findings from this study should help future evaluations of the effectiveness of logging prescriptions in providing adequate den availability for koomal.

Local habitat and landscape affect Ixodes ricinus tick abundances in forests on poor, sandy soils

A large fraction of the forests in northern Belgium consists of homogeneous pine stands on nutrient-poor and acid sandy soils. However, in common with many other parts of Europe, the current forest management aims at increasing the share of deciduous and mixed forests. This might create favourable habitats for the tick Ixodes ricinus, which is Europe’s main vector of Borrelia burgdorferi sensu lato, the causative agent of Lyme borreliosis in humans. Considering the threat to human health, it is important to know which factors regulate tick abundance. The influence of local habitat and landscape variables on the abundance of I. ricinus ticks were studied by collecting questing larvae, nymphs, and adults at 176 locations in forests in the Campine region (northern Belgium). Both I. ricinus ticks and B. burgdorferi spirochetes occurred throughout the study area, which means that the entire region represents an area of risk for contracting Lyme borreliosis. At the forest stand level, the main tree species and the shrub cover significantly affected the abundance of all life stages of I. ricinus. The abundance was higher in oak stands compared to pine stands, and increased with increasing shrub cover. Additionally, at the landscape level, a positive effect was found for forest edge length but not for forest cover. These patterns may be explained by the habitat preferences of the tick’s main hosts. Our results indicate that forest conversion might indeed create suitable habitats for ticks, which highlights the need for intensive information campaigns and effective tick control measures.

Comparing growth and mortality of a spruce budworm (Choristoneura fumiferana) inspired harvest versus a spruce budworm outbreak

Many current forest management regimes stress emulation of natural disturbance events, e.g., spruce budworm (SBW; Choristoneura fumiferana (Clemens)) outbreaks in a balsam fir (Abies balsamea (L.) Mill.) dominated forest, as the preferred method for ensuring sustainability of forest ecosystems. This study compared a SBW-inspired harvest treatment in 25 plots in northern New Brunswick with an uncontrolled SBW outbreak in 30 plots in the Cape Breton Highlands, Nova Scotia. Stand-level measurements before, during, and after each disturbance indicated similar reduction of living stand volume (70% reduction in emulation harvest versus 83% in SBW outbreak), mortality patterns, and lengths of disturbance (4 years of >10% mortality by density of predisturbance stand). Differences for the harvest treatment included higher cumulative postdisturbance blowdown (43% versus 8% of postdisturbance stand density), conversion to hardwood-dominated stands immediately after the disturbance, and faster growth response (immediate release of all species in the harvest treatment versus decreased balsam fir and white spruce (Picea glauca [Moench] Voss) growth and increased white birch (Betula papyrifera Marshall) growth in the SBW outbreak). There were significant differences in stand dynamics following the two disturbances. Results suggest that instead of emulating SBW disturbances, forest managers should be inspired by the spatial and temporal characteristics of SBW-defoliated stands and use significant key features of them to design harvest plans that satisfy management goals.

Birds of One Tree: Participatory Forestry and Land Claims in Tanzania

While approaches to resource management are increasingly popular and offer the promise of economic and political benefits to local communities, they have also been critiqued for extending centralized control of resources, co-opting grassroots resistance, or shifting the burden of project implementation to local residents. Based on ethnographic research in rural Tanzania, this paper examines one pilot program in joint forest management to explore the difficult process and complex effects of participatory management. It examines how the historic competition over land and forest resources informs the contemporary co-management project and how current forest management strategies, such as the taungya system of agroforestry, may subvert local land claims.

Impact of silviculture on dead wood and on the distribution and frequency of tree microhabitats in montane beech-fir forests of the Pyrenees

In forest ecosystems, the level of biodiversity is strongly linked to dead wood and tree microhabitats. To evaluate the influence of current forest management on the availability of dead wood and on the abundance and distribution of microhabitats, we studied the volume and diversity of dead wood objects and the distribution and frequency of cavities, dendrothelms, cracks, bark losses and sporophores of saproxylic fungi in montane beech-fir stands. We compared stands unmanaged for 50 or 100 years with continuously managed stands. A total of 1,204 live trees and 460 dead wood objects were observed. Total dead wood volume, snag volume and microhabitat diversity were lower in the managed stands, but the total number of microhabitats per ha was not significantly different between managed and unmanaged stands. Cavities were always the most frequent microhabitat and cracks the least frequent. Dendrothelm and bark loss were favored by management. Beech (Fagus sylvatica) carried many more microhabitats than silver fir (Abies alba), especially cavities, dendrothelms and bark losses. Fir very scarcely formed dendrothelms. Secondary tree species played an important role by providing cracks and bark losses. The proportion of microhabitat-bearing trees increased dramatically above circumference thresholds of 225 cm for beech and 215 cm for fir. Firs with a circumference of less than 135 cm did not carry microhabitats. In order to conserve microhabitat-providing trees and to increase the volume of dead wood in managed stands, we recommend conserving trees that finish their natural cycle over 10–20% of the surface area.

Effects of the sequence wildfire-harvesting-coppice sprout selection on nutrient export via streamfloe in a small E. globulus watershed in Galicia (NW Spain)

An experimental study was carried out between 1987 and 1999, to assess the effect of the sequence wildfire-clearfelling-coppice sprout selection thinning, on streamflow nutrient export in a Eucalyptus globulus Labill. watershed in Galicia (NW Spain). The effects of such a sequence on nutrient export via streamflow had not been previously evaluated. A wildfire in 1989 caused a significant increase in nutrient exports in streamflow during the following two years. No significant effect was observed the third year after wildfire. After clearfelling in 1992, inputs via precipitation compensated for nutrient exports in streamflow, except for K the first year following harvest and NO3- during the three years after this operation. Coppice sprout selection thinning in 1995 had less effect on nutrient exports than wildfire or harvest. The results presented here could may help in evaluating the effects of current intensive forest management and perturbations that affect eucalypt stands in NW Spain.

Effectiveness of forest management strategies to mitigate effects of global change in south-central Siberia

We investigated questions about the ability of broad silvicultural strategies to achieve multiple objectives (reduce disturbance losses, maintain the abundance of preferred species, mitigate fragmentation and loss of age-class diversity, and sequester aboveground carbon) under future climate conditions in Siberia. We conducted a factorial experiment using the LANDIS-II landscape disturbance and succession model. Treatments included varying the size and amount of areas cut and the cutting method (selective or clearcut). Simultaneously, the model simulated natural disturbances (fire, wind, insect outbreaks) and forest succession under projected future climate conditions as predicted by an ensemble of global circulation models. The cutting method and cutting rate treatments generally had a large effect on species and age-class composition, residual living biomass, and susceptibility to disturbance, whereas cutblock size had no effect. Cutblock size affected only measures of fragmentation, but cutting method and cutting rate often had an even greater effect. Based on the results, we simulated a “recommended” strategy and compared it with the current forest management practice. The recommended strategy resulted in greater forest biomass, increased abundance of favored species, and reduced fragmentation, but it did not significantly reduce losses by disturbance. No single strategy appears able to achieve all possible forest management objectives.

Balancing Multiple Objectives Using a Classification-Based Forest Management System in Changbai Mountains, China

Contemporary forest management often consists of multiple objectives, including restoration of human-impacted forested landscapes toward their range of natural variability (RNV) and sustainable levels of timber production. Balancing multiple management objectives is often challenging due to intrinsic conflicts between these objectives and a lack of reference conditions for evaluating the effectiveness of forest restoration efforts. We used a spatially explicit forest landscape model to assess how well a classification-based forest management (CFM) system could achieve multiple objectives in a Korean pine broadleaf mixed forest ecosystem at Changbai Mountain in Northeast China. The CFM system divided the forest landscape into three management areas (Commercial Forest, Special Ecological Welfare Forest, and General Ecological Welfare Forest), each with its own management objectives and prescriptions, but with an overall goal of increasing the ecological and economic sustainability of the entire landscape. The zoning approach adopted in the Chinese CFM system is very similar to the TRIAD approach that is being advocated for managing public forests in Canada. In this study, a natural disturbance scenario and seven harvest scenarios (one identical to the current harvest regime and six alternative scenarios) were simulated to examine how tree species composition, age structure, and timber production at the landscape level can be affected by different strategies under the CFM system. The results indicated that the current forest management regime would not only fail to reach the designated timber production level but also move the forest landscape far away from its RNV. In order to return the currently altered forest landscape to approach its RNV while providing a stable level of timber production over time, harvest intensities should be reduced to a level that is equivalent to the amount of timber removals that would occur under the natural disturbances; and the establishment of forest plantations is also required.