Forest Management Types Research Articles

Small clear-cuts in managed forests support trap-nesting bees, wasps and their parasitoids

Most forests in Europe are managed but differ in their management intensity. This has different implications for structural- and environmental conditions and subsequently for the conservation of ecological communities, their interactions and functional consequences. Differences in silvicultural treatments, especially those promoting rare habitat structures, could foster trap-nesting bees, wasps and their parasitoids. We therefore tested how forest management and associated vegetation characteristics influence their abundance, richness, parasitism rates and the structure of the bee/wasp-parasitoid networks. Using 180 standardised trap nests on 45 forest plots (1 ha) in the Black Forest, Germany, we compared three management types representing a management intensity gradient: ‘unmanaged’, ‘close-to-nature’, and small ‘clear-cuts’. Host and parasitoid abundance were highest on clear-cut plots and parasitoids were positively influenced by vegetation diversity, whereas bee and wasp richness were highest on clear-cut and close-to-nature plots. The wasp genus Trypoxylon had the highest abundance on clear-cut plots whereas abundance of Deuteragenia was highest on the other management types. Unmanaged plots supported the lowest abundance and richness of the community. Whilst parasitism rate was not directly influenced by management, networks on clear-cut plots were less specialised and more linked. Our results highlight the importance of early successional habitats for trap-nesting bees, wasps and their parasitoids and the subsequent effect on the size and speciality of their networks. We demonstrate that different forest management types lead to changes in habitat suitability for some species, which translates to changes in host-parasitoid networks. Small-scale forest openings such as those created naturally by windthrows, and those created anthropogenically such as small-scale clear-cuts promote forest biodiversity and functions associated to Hymenoptera such as bees and wasps.

Vegetation and Soil Carbon under Various Forest Management Types: Case of Karang Sidemen Community Forest in Lombok, Eastern Indonesia

The condition of community-managed forest areas varies according to biophysics characteristics and management activities. This study aims to investigate the condition of vegetation and soil carbon stocks of various types of forest management by the community in Karang Sidemen Village, Lombok, Indonesia. In the study area, it was found 4 types of landuse management, namely; dense forest-like vegetation (Tp1), moderate vegetation with intensive (Tp2) and less intensive (Tp3) under-stand cultivation, and sparse vegetation resembling dryland agriculture (Tp4). Vegetation condition was analyzed based on satellite derived NDVI index and field observation. Sentinel satellite images for 2015 and 2019, with a resolution of 10x10 m was used. Field data collection was carried out in August 2019. It was made 5 sample plots of 20x20 m for each management type. Vegetation data with diameter (D) ≥ 20 cm, 10 cm ≤D< 20 cm, 2 cm ≤D< 10 cm and D< 2 cm were collected from plots of 20x20 m, subplots 10x10 m, 5x5 m and 2x2 m, respectively. Soil samples were taken diagonally on a 20x20 m plot, at a depth of 0-5 cm, 5-10 cm, 10-20 cm and 20-30 cm. The results showed that the NDVI derived vegetation index for 2015 and 2019 images showed different patterns for the four types of management. The number of species for Tp1, Tp2, Tp3 and Tp4 were 9, 15, 9 and 8 species, respectively. The dominant species are generally from groups of plants providing economic benefits such as avocado (Persea americana), candlenut (Aleurites moluccana), cocoa (Theobroma cacao), coffee (Coffea canephora), jackfruit (Artocarpus heterophyllus), mangosteen (Garcinia mangostana) and guava (Psidium guajava). Soil carbon stocks of the four types of management at a depth of 0-5 cm, 5-10 cm, 10-20 cm and 20-30 cm were18.61-21.04 tons C/ha, 16.56-20.80 tons C/ha, 29.66-34.48 tons C/ha and 27.54 - 33.66 tons C/ha, respectively. The soil carbon stock of denser vegetation is higher than that of medium and sparse vegetation. Therefore, forest management with the community needs to maintain forest-like vegetation.

The effect of small (1-ha), 10-year rotational clear cuts on oak regeneration in Pennsylvania and Michigan

Abstract: We examined oak regeneration in small (2.5-acre [1-ha]) rotational clearcuts in central Pennsylvania and northern Michigan. In central Pennsylvania this approach was initiated to improve habitat for ruffed grouse and other early successional wildlife species, while in Michigan it was used to regenerate oak under harsh environmental site conditions associated with sandy soils and early frosts. In our study areas most of the small clearcut stands had greater oak regeneration than was found in a large 39.5-acre (16-ha) clearcuts. In particular, 10-year-old 2.5-acre (1-ha) clearcut stands located within a landscape of previous rotational cuts and remnant mature forest had adequate advanced oak regeneration compared with other age classes. We demonstrate that oak regeneration can be achieved within this type of landscape due to the availability of seed source within small clearcuts from adjacent forest and the reduction of herbivory by white-tailed deer due to an overall availability of plant resources. Therefore, if a rotational clearcut cycle is maintained over time, early successional wildlife habitat can be maintained while the objectives of forest regeneration are met. This type of forest management may be particularly applicable in areas where fire cannot be used to regenerate oak.

The challenges and opportunities in developing empowerment programs for communities living surrounding the forest with special purposes

Forest with Special Purpose (FwSP) is the type of forest management in Indonesia, which involves a university or training center as the main caretaker. FwSP is specifically designated to advance forestry’s research and development, education, and training in Indonesia. This article aims at mapping the problems the management of FwSP facing in dealing with the communities living surrounding the FwSP. It requires strong collaboration between local people and the FwSP to ensure that FwSP is able to preserve forest sustainability. The research utilizing mix method to collect the data from all universities FwSPs in Java Island, through online questionnaires and in-depth interviews with the directors of FwSP. The findings show FsWP face medium to serious challenges with regard to creating cooperation with local people. While all FwSP has created and implemented community development programs, building strong cooperation with local people is perceived to still require a long way to go to succeed. Most of FwSP targeted the activities to improve the quality of life i.e. alternative sources of income for local people. Developing local tourism with FwSP as the destination and involving local in developing the destination is one main long-term program agreed upon by the majority of FwSP directors.

Skidders Fuel Consumption in Two Different Working Regions and Types of Forest Management

For the needs of fuel consumption analysis, a database for a period of 2 years was created for three types of skidders operating in two different management methods—even-aged and selective forests. A total of 436 skidders were processed in the database, of which 255 skidders worked in even-aged forests and 181 skidders worked in selective forests. The average consumption of skidders in even-aged forests ranged from 1.38 to 1.65 L/m3 or from 7.81 to 9.34 L/PMH, while in selective forests, the average consumption ranged from 1.06 to 1.34 L/m3 or from 6.49 to 7.10 L/PMH. The obtained results indicate higher fuel consumption for all three types of skidders in regular forest management. There is no statistically significant difference in fuel consumption between the studied skidders. Comparing fuel consumption in L/PMH, we notice that there was an increase in fuel consumption in relation to the age of the skidder.

Exploring the biodiversity of key groups in coppice forests (Central Italy): the relationship among vascular plants, epiphytic lichens, and wood-decaying fungi

Sustainable Forest Management (SFM) indicators consider the main ecological and socioeconomic functions of forests but do not currently include some key groups widely adopted to assess the effects of forest management, such as herbaceous vascular plants, epiphytic lichens, and wood-decay fungi. Moreover, they are shaped into high forests while in the Mediterranean area the oldest type of forest management is coppice. We investigated the diversity and the relationships of the above-mentioned groups of taxa in three European Forest Types (EFTs) to contribute to the selection of indicator species suitable for monitoring Mediterranean coppice forests. We find only a weak cross-taxon congruence between vascular plants and lichens on considering the whole dataset, while no significant correlations are evident within the three EFTs. Species richness was significantly different among EFTs, being Thermophilous deciduous forests the richest, both considering the groups of taxa separately and the total species richness. As for species composition, significant differences were found both for the whole dataset and also for pairwise comparisons among EFTs. We provided a dwelling-species list of the three key groups of taxa, which could be suitable for monitoring the sustainability characteristics of fragmented and low continuity forests such as coppice stands.

Estimation of trees height and vertical structure using SAR interferometry in uneven-aged and mixed forests.

Estimation of forest height is an important parameter of stands structure that aids in the determination of forest biomass, successional stage dynamics, and the decision of the type of forest management. In addition, estimating the height of trees especially in uneven-aged, massive, and multi-storied forest stands always faces challenges in kind of inventory and accuracy of the assessment. In this research, the synthetic aperture radar (SAR) interferometry technique was used to estimate the height of trees for determining the vertical structure of forest. For this purpose, we focused on an area at the mixed and uneven-aged forest in Iran and evaluated the potential of Envisat ASAR data to characterize the tree height in the forest patches and the digital surface model (DSM) was produced via SAR interferometry. The height of trees and the vertical structure of the forest stands were estimated using produced DSM and Digital elevation Model (DEM). Furthermore, the accuracy of estimated parameters was evaluated with real ground data (11 × 1ha (100 × 100m) sample plots). The results indicated that the estimated height of trees was meanly 7.69m with a 22m STDV over the reality. Furthermore, the vertical structure in all the plots was three-storied that they are the same as ground truth, but the percentage of the share of trees in the under and middle story was different from the ground truth. In conclusion, the tree height and vertical structure of forest stands can be determined with acceptable accuracy via SAR interferometry and Envisat ASAR data.

Vascular epiphyte diversity and host tree architecture in two forest management types in the Himalaya

Epiphytes are one of the most diversified plant life forms, whose species richness peaks in the tropics and subtropics. Here we examined vertical distribution metrics (i.e., number of epiphyte individuals and epiphyte species richness) of vascular epiphytes (i.e., orchids and ferns) on two dominant host trees (i.e., Schima wallichii (DC.) Korth. and Quercus lanata Sm.) in sub-tropical forests of Nepal. We sampled a total number of 72 host trees of Q. lanata and S. wallichii from two forest sites: a government protected national park forest and community managed forest. We applied generalized linear mixed models and Kruskal-Wallis rank sum tests to explain epiphyte diversity by tree architecture (i.e., diameter at breast height, tree height, crown size, number of forks, bark rugosity, bark pH and tree layer), host species and forest management types. After variable selection via multi-model inference technique, we found diameter at breast height to be the most powerful and significant explanatory variable for the number of epiphyte individuals and epiphyte species richness across host tree species, tree layers, and forest management types. Interestingly, epiphyte diversity was on average higher in the community managed forest than in the national park forest, on S. wallichii than on Q. lanata and particularly on the trunk below forks. We conclude that effective conservation of epiphyte diversity in the Nepal Himalaya requires conservation of old-growth host trees through community approaches. If large and old tree stands are maintained, community managed forests can host high diversity of vascular epiphytes and provide ecosystem goods to local people alike.

Mapping regional forest management units: a road-based framework in Southeastern Coastal Plain and Piedmont

Management practices are one of the most important factors affecting forest structure and function. Landowners in southern United States manage forests using appropriately sized areas, to meet management objectives that include economic return, sustainability, and esthetic enjoyment. Road networks spatially designate the socio-environmental elements for the forests, which represented and aggregated as forest management units. Road networks are widely used for managing forests by setting logging roads and firebreaks. We propose that common types of forest management are practiced in road-delineated units that can be determined by remote sensing satellite imagery coupled with crowd-sourced road network datasets. Satellite sensors do not always capture road-caused canopy openings, so it is difficult to delineate ecologically relevant units based only on satellite data. By integrating citizen-based road networks with the National Land Cover Database, we mapped road-delineated management units across the regional landscape and analyzed the size frequency distribution of management units. We found the road-delineated units smaller than 0.5 ha comprised 64% of the number of units, but only 0.98% of the total forest area. We also applied a statistical similarity test (Warren’s Index) to access the equivalency of road-delineated units with forest disturbances by simulating a serious of neutral landscapes. The outputs showed that the whole southeastern U.S. has the probability of road-delineated unit of 0.44 and production forests overlapped significantly with disturbance areas with an average probability of 0.50.

ЭКОНОМИЧЕСКИЕ АСПЕКТЫ ОРГАНИЗАЦИИ КАРБОНОВЫХ ФЕРМ НА ЛЕСНЫХ ЗЕМЛЯХ

The article considers the possibilities of developing forest entrepreneurship through expanding the range of ecosystem services and organizing sequestration Inustry on forest lands. The new type of forest management is based on the ability to balance carbon dioxide emissions into the atmosphere. The economic aspects of creating and using forest carbon farms are considered. To determine the standard costs for creating poplar and pine carbon plantations, the standard method was used. Creating carbon farms on forest land is a costly process, but carbon storage activities can bring numerous economic and environmental effects in addition to maintaining the carbon balance. The cost of creating one hectare of forest carbon farm is from 262 to 304 thousand rubles, while the economic effect of their use can significantly exceed the investment. The first stage in the organization of carbon farms should be the creation of test plantations-carbon polygons. It is proved that the necessary resources and prerequisites are available for the implementation of the actual practice-oriented task of creating carbon polygons in the Voronezh region.

Principles for assessing forest management risks associated with natural hazards

Subject. This article examines the risks associated with the loss of ecological and resource potential of forests, and those affecting timber harvesting activities. Objectives. The article aims to develop and test methodological approaches and principles for assessing risks to certain forest management types associated with natural hazards. Methods. For the study, we used the methods of general scientific research, statistical, comparative, logical, and geoinformation analyses. Results. The article presents a developed method of calculating the environmental and economic damage to the fir forests of Western Siberia as a result of the invasion of bark beetles, Polygraphus proximus Blandford. It describes the main natural factors that disrupt the operation of special equipment and the conditions for harvested wood transportation and assesses the most likely risks of logging activities in winter. The testing of a comprehensive assessment of forest risks at the regional level shows the region's area differences in terms of risk both for individual natural hazard factors and in their totality. Conclusions. Forest management risk analysis can be successfully implemented through using methods based on general scientific principles. Specially designed approaches should be used to address narrowly focused industry challenges.

森林管理的生态效应研究进展

森林管理是实现森林生产效益最大化的主要措施，是增加碳吸收以减缓气候变暖的关键手段，是调节区域水文循环的有效途径，是保护地以外实现生物多样性保护目标的重要补充。然而，追求单一生产功能的传统森林管理弱化了其他生态功能，并对森林景观结构和生物多样性产生负面影响。全球80%以上森林由于人类活动呈现不同程度退化进而影响人类福祉，森林管理需要优化以追求多维生态功能的协同共赢。当前，对于森林管理的生态效应仍有较多争论或未形成明确认识，可持续森林管理能否取得额外的气候效益仍有待确认，森林管理如何影响不同区域的水文生态功能仍未形成明确认识，不同类型森林管理或多或少、或正面或负面影响栖息地及不同种类生物多样性的强度和方向不明确。因此，森林管理的生态效应是一个值得深入探索的问题，未来需要深入量化不同管理措施对气候变化缓解、水文循环调节、生物多样性保护乃至提供其他生态功能的作用，将维持或提升生态功能及生物多样性作为可持续森林管理的一个重要目标，通过优化森林管理策略开展森林提质增效以获得最大收益。;Forest management is considered to be the main measurement to maximize the benefit of forest commodity production, and the key method to increase carbon absorption to mitigat climate warming. It is also the effective way to regulate regional hydrological cycle, and the important supplement to achieve the goal of global biodiversity conservation besides the protected areas. However, the traditional forest management, which pursues a single production function, weakens other ecosystem functions and services, and has negative impacts on the forest landscape and biodiversity. More than 80% of the world's forests have different degrees of degradation due to human activities, and thus affects human well-beings. Therefore, it is necessary to transfer from traditional forest management to optimizing forest management. The optimizing forest management can promote multi-dimensional functions of ecological, economic, social and cultural aspects, and can achieve the win-win goals of wood production, biodiversity conservation, climate mitigation, hydrological regulation and other ecosystem functions. In this paper, we briefly reviewed the research progress on the ecological effects of forest management. At present, there are still many controversies about the ecological effects of forest management, or have not formed a clear understanding. Whether sustainable forest management can achieve additional climate benefits, and whether it can achieve climate mitigation goals, remains to be confirmed. How forest management impacts runoff and water quality in different regions has not been clearly recognized, which is an important issue worthy of in-depth and comprehensive analysis. Furthermore, the more or less intensity, and positive or negative impacts from different types of forest management on habitat and biodiversity are unclear. It is necessary to quantify the impacts of different management measurements on the forest animals, plants and microorganisms, and to maintain or improve biodiversity as an important goal of sustainable forest management. Therefore, how to optimize the forest management to obtain the maximum benefits is a research focus worthy of further exploration. In the future, it is necessary to quantify the effects of different forest management measurements on climate change mitigation, hydrological regulation, biodiversity conservation, and other ecosystem functions.

A Review of Forest Management Effects on Terrestrial Leaf Litter Inhabiting Arthropods

Leaf litter arthropods are some of the most abundant and diverse communities in forests and provide myriad ecosystem services from decomposition and mineralization to pollination and predation. They are important to forest health and management and, in turn, are affected by how we manage our forests. Various forest management techniques such as clear cutting, burning, and chemical control of invasive species all have differing effects on ground dwelling arthropods and, despite their importance, a review of the literature on these effects does not currently exist. My objective with this paper is to review the effects of different types of forest management on arthropods in leaf litter systems.

Short-term effects of forest management on soil microbial biomass and activity in caatinga dry forest, Brazil

The Caatinga is among the most threatened and least studied tropical dry forests in the world. Sustainable forest management is a rational exploitation practice adopted in the biome, but it can impact a variety of ecosystem attributes. We still have a limited understanding of forest management impacts on the soil, especially on microbial biomass. Thus, we developed this work by asking how do soil microbial biomass and activity respond in the short-term to Caatinga forest management and how do these responses differ between forest management practices? Three types of forest management were evaluated (clear cutting - CC, selective cutting by diameter - SCD, and selective cutting by species - SCS), using unmanaged Caatinga (UC) as a reference. Litter and soil (depth of 0–10 cm) collections were carried out. Soil microbial activity was determined based on the amount of evolved CO2, and the microbial biomass C and N were estimated by the fumigation-extraction method. The management provided a reduction in leaf litter (CC = 16%; SCD = 25%; SCS = 38%; UC = 55%) and an increase in branch litter (CC = 73%; SCD = 66%; SCS = 46%; UC = 35%). It also caused a 42% reduction in MB-C. The metabolic quotient had an increase in CC and SCD management (average of 690.6 mg g−1 day) compared to UC (365.9 mg g−1 day). SCD and CC influenced the activity and C transformation of soil microbial biomass in the short-term, while SCS less intensely affected these variables, approaching the unmanaged forest condition.

Divergent drivers of the microbial methane sink in temperate forest and grassland soils.

Aerated topsoils are important sinks for atmospheric methane (CH4 ) via oxidation by CH4 -oxidizing bacteria (MOB). However, intensified management of grasslands and forests may reduce the CH4 sink capacity of soils. We investigated the influence of grassland land-use intensity (150 sites) and forest management type (149 sites) on potential atmospheric CH4 oxidation rates (PMORs) and the abundance and diversity of MOB (with qPCR) in topsoils of three temperate regions in Germany. PMORs measurements in microcosms under defined conditions yielded approximately twice as much CH4 oxidation in forest than in grassland soils. High land-use intensity of grasslands had a negative effect on PMORs (-40%) in almost all regions and fertilization was the predominant factor of grassland land-use intensity leading to PMOR reduction by 20%. In contrast, forest management did not affect PMORs in forest soils. Upland soil cluster (USC)-α was the dominant group of MOBs in the forests. In contrast, USC-γ was absent in more than half of the forest soils but present in almost all grassland soils. USC-α abundance had a direct positive effect on PMOR in forest, while in grasslands USC-α and USC-γ abundance affected PMOR positively with a more pronounced contribution of USC-γ than USC-α. Soil bulk density negatively influenced PMOR in both forests and grasslands. We further found that the response of the PMORs to pH, soil texture, soil water holding capacity and organic carbon and nitrogen content differ between temperate forest and grassland soils. pH had no direct effects on PMOR, but indirect ones via the MOB abundances, showing a negative effect on USC-α, and a positive on USC-γ abundance. We conclude that reduction in grassland land-use intensity and afforestation has the potential to increase the CH4 sink function of soils and that different parameters determine the microbial methane sink in forest and grassland soils.

Формирование стратегии устойчивого управления лесами

The paper is focused on the problem of developing a strategy for sustainable forest management and the forest sector of the economy of the territories. The aim is to improve approaches to its creation based on an ecosystem approach to generating real economic incomes from forest products and forest services and improving the environment. For this, the conceptual framework of the study based on the ecosystem approach is substantiated, considering the relationship between ecosystem services of the forest and various forms of their contribution to the economic development of territories, taking into account the forest and non-forest sectors of the economy. To determine the ecosystem services of the forest, the methods of direct counting, compara-tive analysis, assessment of “willingness to pay”, assessment of the carbon budget, etc. were used. The study of the economic value of the ecosystem services of the forest of transboundary territories showed the differences between the direct and indi-rect contribution of forests to the economy of the regions, which are determined by climatic features, the state of the forest fund, the degree of forestry activities, applied methods of forest management and forest use. The study made it possible to devel-op strategic directions for sustainable management of forest ecosystem services in transboundary terri-tories and to draw a conclusion about the need to move from a conservation type of forest manage-ment to the principles of sustainable development based on the preservation and enhancement of the economic, social and ecological value of forests.

Influence of Acacia mangium on Soil Fertility and Bacterial Community in Eucalyptus Plantations in the Congolese Coastal Plains

Productivity and sustainability of tropical forest plantations greatly rely on regulation of ecosystem functioning and nutrient cycling, i.e., the link between plant growth, nutrient availability, and the microbial community structure. So far, these interactions have never been evaluated in the Acacia and Eucalyptus forest planted on infertile soils in the Congolese coastal plains. In the present work, the soil bacterial community has been investigated by metabarcoding of the 16S rRNA bacterial gene in different stands of monoculture and mixed-species plantation to evaluate the potential of nitrogen-fixing trees on nutrient and bacterial structure. At the phylum level, the soil bacterial community was dominated by Actinobacteria, followed by Proteobacteria, Firmicutes, and Acidobacteria. A principal coordinate analysis revealed that bacterial communities from pure Eucalyptus, compared to those from plantations containing Acacia in pure and mixed-species stands, showed different community composition (beta-diversity). Regardless of the large variability of the studied soils, the prevalence of Firmicutes phylum, and lower bacterial richness and phylogenic diversity were reported in stands containing Acacia relative to the pure Eucalyptus. Distance-based redundancy analysis revealed a positive correlation of available phosphorus (P) and carbon/nitrogen (C/N) ratio with bacterial community structure. However, the Spearman correlation test revealed a broad correlation between the relative abundance of bacterial taxa and soil attributes, in particular with sulfur (S) and carbon (C), suggesting the important role of soil bacterial community in nutrient cycling in this type of forest management. Concerning mixed plantations, a shift in bacterial community structure was observed, probably linked to other changes, i.e., improvement in soil fertility (enhanced P and C dynamics in forest floor and soil, and increase in soil N status), and C sequestration in both soil and stand wood biomass with the great potential impact to mitigate climate change. Overall, our findings highlight the role of soil attributes, especially C, S, available P, and C/N ratio at a lesser extent, in driving the soil bacterial community in mixed-species plantations and its potential to improve soil fertility and to sustain Eucalyptus plantations established on the infertile and sandy soils of the Congolese coastal plains.

Effect of Forest Management Types on Soil Carbon Stocks in Montane Forests: A Case Study of Eastern Mau Forest in Kenya

Mau Forest, a major forest reserve in Kenya, has experienced anthropogenic disturbances through encroachment and forest fires. This study aimed at comparing the soil carbon stocks in different forest management types as well as how seasonal climatic changes influence its dynamics. The study was undertaken in the Eastern Mau block (Sururu) which forms part of the greater Mau Forest Complex. The forest management interventions have been in place for over 15 years with disturbed (fire) natural forest experiencing fires in 2005, 2007, and 2014 while cypress plantations were established in 1994. A nested experimental design was used in data collection, where thirty-two sample plots were nested into four blocks each measuring 100 m2 delineated by forest management types (disturbed by fire, natural forest, undisturbed natural forest, plantation, and glades). In each plot, data on soil carbon stocks, soil bulk density, soil moisture, and temperature were collected for both dry and wet seasons. Data collection was carried out between November 2015 and December 2016. The results indicated that there were no significant differences in the carbon stocks among the forest management types (F4,16 = 0.61, P = 0.613 ). However, seasonal weather changes significantly affected the amount of carbon stocks among the forest management types (F4,16 = 0.61, P > 0.05 ). The undisturbed natural forest had the highest mean soil carbon stocks, while the plantation forest had the lowest as follows: undisturbed natural forest (135.17 ± 35.99.0 Mg·C−ha), disturbed natural forest by fire (134.52 ± 38.11 Mg·C−ha), glades (122.4 ± 64.9 Mg·C−ha), and plantation forest (116.51 ± 39.77 Mg·C−ha). Furthermore, the undisturbed natural forest management had the highest bulk density (0.66 g/cm3), while the disturbed (fire) natural forest had the lowest (0.59 g/cm3). These values were low compared to most normal mineral soils which have a bulk density of between 1.0 g/cm3 and 1.5 g/cm3. There was a significant ( P > 0.01 ) relationship between seasonal weather (temperature) changes and soil carbon stocks under different forest management types with the relationship being stronger in soils under glades (r2 = 0.62) and weak in the undisturbed natural forest (r2 = 0.26). In conclusion, forest disturbances have an impact on soil carbon stocks, and for effective management of forest towards climate stabilization, then disturbance should be minimized if not avoided.

Influences of forest gaps on soil physico-chemical and biological properties in an oriental beech (Fagus orientalis L.) stand of Hyrcanian forest, north of Iran

Abstract: Understanding the effects of silvicultural practices including single-tree selection on soil properties is essential for forest management in temperate broadleaved beech forests. Changes in physico-chemical and biological soil properties in 15 harvest-created gaps under single-tree selection and the adjacent closed canopies, with five replications for each, were studied 6 years after gap creation in an oriental beech (Fagus orientalis L.) stand of the Hyrcanian forest. Gaps were classified into three size classes: small (85-130 m2), medium (131-175 m2) and large (176-300 m2). Soil cores were collected at the center and at the edge of gaps, and under the adjacent closed canopy. Results indicated that gap size significantly affected soil texture and bulk density, whereas soil organic carbon (SOC), total nitrogen and pH showed a significant gradient from the center to the edge of gap independently form their size. SOC and total nitrogen at the center of gaps were also significantly lower than closed-canopy, in particular for the medium-gap; contrastingly, the bulk density with the highest mean value was found at the center of the large-gap. Gap size had no significant influence on soil microbial biomass. These results highlighted that similar conditions in terms of many soil properties were still present among gaps and adjacent closed-canopy stands six years after logging, though canopy openness triggered a reduction in carbon and nitrogen availability along with the related microbial activity at the center of gaps, independently from their size. Therefore, if aimed at preserving an uneven aged structure along with soil quality in temperate broadleaved deciduous forest as the oriental beech stands in the Hyrcanian region, single-tree selection practice for harvesting trees can be recommended as sustainable forest management type.

Forest management, canopy cover and geographical distance affect saproxylic beetle communities of small-diameter beech deadwood

Beetles (Coleoptera) are the most diverse and species-rich insect order in saproxylic communities, and play a key role in forest dynamics. To prioritize conservation measures, a clear understanding is needed of what habitat features are the most important for beetles that depend on deadwood. Here, we investigate (i) how the assemblages of saproxylic beetles emerging from small-diameter beech deadwood (Fagus sylvatica L.) are influenced by several environmental factors and type of forest management, and (ii) if geographical distance of the investigated sites influences the similarity of these saproxylic beetle assemblages. We visited 10 high beech forest stands along a latitudinal gradient from northern to southern Italy, and collected 200 logs of 50 cm length, 12 ± 2 cm diameter, and Hunter’s decay class 2, from deadwood lying on the forest floor. Logs were stored in ex-situ emergence traps, in common garden conditions, from April to September, and individuals emerging from the deadwood were collected weekly. A total of 2571 beetles were collected, including several species which were either threatened, firstly recorded or endemic. We found that, compared to even-aged stands, forests managed to increase structural heterogeneity (uneven-aged high forests, and former coppice stands converted to high forest), with closed canopy, were colonized by the richest and most abundant saproxylic beetle assemblages. Additionally, we observed distance decay of similarity between sites, indicating geographical structure in community composition. Our findings have important implications for biodiversity conservation in beech forests: (1) small-diameter deadwood hosts a rich biodiversity of Coleoptera and should therefore be left on the ground; (2) forest management practices should aim at preserving or restoring structural heterogeneity and closed canopies; (3) these conservation measures should be carried out along the entire area of occurrence of beech forests, due to turnover in species composition with geographical distance.