Live fences and landscape connectivity in a neotropical agricultural landscape

Live fences are common elements in neotropical agricultural landscapes and could play important roles in the conservation of biodiversity by enhancing landscape connectivity, however, little is known about their abundance and spatial arrangement. The objectives of this study were to characterize the abundance and spatial patterns of live fences in a fragmented landscape dominated by pastures in Río Frío, Costa Rica, to determine their contribution to landscape structure and connectivity and to examine their role as tools for landscape conservation planning. Live fences accounted for 45.4% of all fences in the landscape and occurred with a mean density of 50.5 linear meters per hectare. Although live fences covered only a small total area of the landscape (<2%), they had an important effect on landscape structure and connectivity, increasing total tree cover, dividing pastures into smaller areas, creating rectilinear networks that cross the landscape and providing direct physical connections to forest patches. Simulations showed that the conversion of all existing wooden fences to live fences would greatly enhance landscape connectivity by more than doubling the area, density and number of direct connections to forest habitats, and reducing the average distance between tree canopies. Our study demonstrates that live fences play key roles in defining the structure and composition of neotropical agricultural landscapes and merit consideration in both conservation efforts and agricultural policies designed to enhance landscape connectivity and promote biodiversity conservation.     

Private Ownership and Public Good Provision in English Woodlands

There is increasing emphasis on multipurpose forestry within UK national and regional forest strategies, with the aim of co-delivering the social, environmental and economic benefits of woodlands. Private woodland ownership is also changing, with an increase in owners without a farming or forestry background. However, there is little substantive evidence relating to the motivations of private woodland owners and, in particular, their ability and willingness to deliver public goods. A qualitative study is adopted, using semi-structured interviews in three areas in England, to address this theoretical gap. Exploratory findings indicate that private woodland owners have a diverse range of objectives, motivations and management regimes which influence the potential for public good delivery. It is shown that some private woodland owners, such as those less motivated by economic return, may be better placed than others to deliver certain public goods; that conflicts can arise between the provision of recreation and nature conservation, especially in smaller woodlands; and that many private woodland owners are sceptical about becoming involved in grant schemes which may help foster public good provision in the private sector.     

Estimating breast height diameter and volume from stump diameter for three economically important species in Turkey

Abstract

In Fennoscandia, the concept of woodland key habitats has become one of the key concepts when defining hotspots for forest biodiversity. There is a serious lack of studies, however, in which the diversity value of the assumed key habitats has been assessed for any groups of organisms. The aim of this study was to investigate whether the woodland key habitats as defined in the Finnish Forest Act can be advocated as diversity hotspots for polypores, a group of wood-decaying fungi including several red-listed species and species used as indicators for conservation value of forests. The study area was situated in the southern boreal zone, in eastern Finland. In total, 72 woodland key habitat sites representing six different habitat types, and 12 production forest sites as controls were investigated for their polypore assemblages. A total of 2077 records of 93 species was made, of which only 17 records of nine species were red-listed. On average, key habitats hosted more species than control forests, but of the six habitat types, only fresh and mesic–moist herb-rich forests differed significantly in species number from the control forests. Compared with control forests, key habitats can maintain rich polypore flora but, because of the low number of red-listed species found, they are likely to be of little help in the conservation of threatened polypores.     

Distribution patterns of acorns after primary dispersion in a fragmented oak forest and their consequences on predators and dispersers

Forest fragmentation affects seed production, but little is known about how seeds are distributed in fragmented forests after primary dispersion and how this affects their interactions with other organisms. This study addressed these issues in a fragmented oak forest of Quercus laeta where four habitat types were recognized: interior and edge of patches, deforested matrix around patches, and an abandoned field. Areas and distances to the abandoned field were measured for 40 patches, and acorns were sampled in all habitats. Only samples from the interior and edge of patches had acorns, which were classified as aborted, viable, and parasitized by insects or fungi. Acorns in all these classes were regressed against patch area and distance to the abandoned field. Field experiments were also conducted to determine whether acorn removal rates varied across habitats. Aborted acorns within patches were not related to area or distance, but they decreased with increasing values of both variables at patch edges. Within patches, viable acorns were positively related to increases in area and distance, while the converse occurred for insect-damaged acorns; fungal-infested acorns were not related to patch variables in this habitat. Complex interactions between area and distance explained how acorns in these classes were distributed across patch edges. Acorn removal was higher within patches and their edges when compared to human-disturbed habitats; both mice and birds were identified as potential acorn dispersers. These results suggest that forest fragmentation affects acorn-mediated processes and that this may influence the recovery of patch connectivity in the landscape.     

丽江拉市海国际重要湿地生态修复方案探究

拉市海国际重要湿地是我国重要的候鸟越冬栖息地之一,针对其整体环境整治问题,地方政府和管理部门做了大量工作,取得了较好成效,但还存在退化沼泽湿地急需修复、退养鱼塘急需生态修复、入湖河道急需治理等问题,基于此,提出退化沼泽湿地、退塘还湿、入湖河段生态修复以及破碎化湖滨带治理、外来物种防控等生态修复方案。通过湿地生态修复,湿地整体生态环境得到改善,候鸟栖息地、食源地得到修复,湿地植被和生物多样性明显增加,湿地景观得到优化,湿地生态服务功能有所提高。     

广东省水鹿的分布格局与保护对策*

水鹿（Cervus equinus）保护及其生境的规划需要明确其在不同空间尺度的分布格局而采取相对应的措施。该文基于实地调查和文献资料分析,研究了广东省水鹿在省级和保护区级两种空间尺度下不同生态功能区的分布格局。结果表明,在广东省,水鹿主要分布于南岭中亚热带常绿阔叶林生物多样性保护与水源涵养生态区,其分布区域属省级生态功能区,生境质量较好,保护地位重要;在车八岭国家级自然保护区,水鹿多活动于人为干扰大的缓冲区与实验区,保护程度有待提高。建议以自然保护区为节点基础,开展就地保护;在条件较好的保护区之间建设大型生态廊道,增加破碎化生境的连通性,加强水鹿个体交流;同时应在保护区实施“全区覆盖”式管理,特别是在缓冲区和实验区严格控制人为干扰,加强对水鹿及其生境的巡护管理。     

Natural reforestation is changing spatial patterns of rural mountain and hill landscapes: A global overview

The present landscape structure and function is the result of centuries of changes produced both by natural processes and human driving forces. For centuries many mountain and hillside areas have been the subject of deforestation to create space for agriculture and grazing, although the abandonment of traditional mountain agriculture has produced a natural forest recovery in many regions of the world. The physical changes imposed on the landscape by the development of secondary woodland have brought both positive and negative consequences, depending on the geographical and economic context and on the scale of the sites. Among the ecological problems caused by natural reforestation, one of great interest is the reduction of open spaces resulting in a loss of landscape heterogeneity and mosaic features. This review paper focused its attention on landscape metrics or indices that are frequently used to assess the structural characteristics of the landscape and to monitor changes in land use: mean patch size (MPS), connectivity (CONN), boundary length (BL) and the patch number (NP). Through the analysis of 52 selected papers and 53 case studies, we identified the main gaps in current knowledge, providing directions for further research. Most of the reviewed studies focused only on a portion of the spatial attributes that we were interested in and only 32 case studies reported accurate data both on forest expansion rate and time range analyzed in the study area. We conclude that the study of changes in all the spatial attributes considered within the same case study is a key to explain ecological consequences in mosaic cycles or in stochastic dynamic landscapes that emerged from the interplay of several processes, and to predict and explain their spatial and temporal characteristics. The current knowledge of how changing spatial attributes affect biodiversity, habitats, and ecosystem functions is limited by the scarcity of studies that explicitly consider the shifting in time of the four spatial attributes together.     

Biodiversity management approaches for stream–riparian areas: Perspectives for Pacific Northwest headwater forests,microclimates, and amphibians

Stream–riparian areas represent a nexus of biodiversity, with disproportionate numbers of species tied to and interacting within this key habitat. New research in Pacific Northwest headwater forests, especially the characterization of microclimates and amphibian distributions, is expanding our perspective of riparian zones, and suggests the need for alternative designs to manage stream–riparian zones and their adjacent uplands. High biodiversity in riparian areas can be attributed to cool moist conditions, high productivity and complex habitat. All 47 northwestern amphibian species have stream–riparian associations, with a third being obligate forms to general stream–riparian areas, and a quarter with life histories reliant on headwater landscapes in particular. Recent recognition that stream-breeding amphibians can disperse hundreds of meters into uplands implies that connectivity among neighboring drainages may be important to their population structures and dynamics. Microclimate studies substantiate a “stream effect” of cool moist conditions permeating upslope into warmer, drier forests. We review forest management approaches relative to headwater riparian areas in the U.S. Pacific Northwest, and we propose scenarios designed to retain all habitats used by amphibians with complex life histories. These include a mix of riparian and upslope management approaches to address the breeding, foraging, overwintering, and dispersal functions of these animals. We speculate that the stream microclimate effect can partly counterbalance edge effects imposed by upslope forest disturbances, hence appropriately sized and managed riparian buffers can protect suitable microclimates at streams and within riparian forests. We propose one approach that focuses habitat conservation in headwater areas – where present management allows extensive logging – on sensitive target species, such as tailed frogs and torrent salamanders that often occur patchily. Assuming both high patchiness and some concordance among the distribution of sensitive species, protecting areas with higher abundances of these animals could justify less protection of currently unoccupied or low-density habitats, where more intensive forest management for timber production could occur. Also, we outline an approach that protects juxtaposed headwater patches, retaining connectivity among sub-drainages using a 6th-field watershed spatial scale for assuring well-distributed protected areas across forested landscapes. However, research is needed to test this approach and to determine whether it is sufficient to buffer downstream water quality and habitat from impacts of headwater management. Offering too-sparse protection everywhere is likely insufficient to conserve headwater habitats and biodiversity, while our alternative targeted protection of selected headwaters does not bind the entire forest landscape into a biodiversity reserve.     

Landscape genetics highlight the importance of sustainable management in European mountain spruce forests: a case study on Western capercaillie

The mountain spruce forests of the Western Carpathians have experienced a dramatic deterioration in the last decades increasing the landscape fragmentation. This considerably affected the Western capercaillie population recently surviving within small habitat patches surrounded by unfavourable habitats. Our study shows that the long-term isolation resulted in genetic differentiation with decreasing trend in allelic richness towards the most adjacent western subpopulations. We evaluated dispersal possibilities within the landscape and identified barriers and the most critical corridors between genetically distinct subpopulations. Landscape genetic analysis confirmed that the isolation by environmental features explains the observed genetic patterns better than straight geographical distance. We highlight the urgent need for an active conservation management in the critical habitats where dispersion might be constrained or “bottlenecked” in order to ensure gene flow within the fragmented capercaillie metapopulation of the Western Carpathian mountain forests.     

The confluence of landscape context and site-level management in determining Midwestern savanna and woodland breeding bird communities

Species distributions are determined by complex interplays between multi-scale factors. Conservation management, however, often occurs at a single scale of the site level. This is true for bird communities of restored savannas and mixed woodlands in the central U.S. In this region, many historic open-canopy oak savanna habitats have become closed canopy mixed woodlands due to loss of landscape-scale disturbance from fire and grazing. Site-level management efforts return some mixed woodland habitats back to savanna through fire and mechanical thinning. Savanna and woodland historically formed complex mosaic landscapes at the ecotone between prairies and Eastern deciduous forests and now exist within landscapes that vary in amount of open (e.g., perennial grassland and row crop agriculture) and woodland habitat. To understand the interplay between site and landscape level factors in savanna restoration, we sampled the breeding bird community in four combinations of site and landscape: restored savanna in open landscapes, restored savanna in woodland landscapes, and closed canopy woodland in both landscapes. We found that the outcome of site-level savanna restoration depended on the surrounding landscape. Compared to other treatment types, restored savannas in open landscapes supported a distinctive bird community characterized by high species richness, bird abundance, and percent of ground feeders, shrub nesters, and edge species. Both savanna and woodland sites in the open landscape had a higher percent of species of conservation concern, while at both site and landscape levels, woodland was associated with a higher percent of area sensitive species and habitat specialists. Our results suggest savanna restoration efforts should focus on sites that exist either in open country or on edges where closed canopy forest meets open country. This strategy would combine site and landscape level benefits of savanna restoration for avian diversity, while also preserving the conservation benefits of large tracts of intact forest.     

Ecological thresholds in herb communities for the management of suburban fragmented forests

Fragmentation is a major cause of biodiversity loss. The relationship between fragmentation and biodiversity might be non-linear, due to the presence of ecological thresholds; however, the application of the threshold concept on the conservation of herb biodiversity has received limited attention. We assessed the relationship between a pool of woodland indicators and features of forest fragments (area, isolation, shape), and we evaluated whether ecological thresholds might provide guidelines for conservation. We performed our study in a human dominated area of northern Italy. In order to obtain a group of floristic indicators, we chose perennial herbs characteristic of the phytosociological syntaxa Fagetalia sylvaticae, Carpinion betuli and Erythronio-Carpinion, with suitable Landolt L and H index, obtained from previous relevés in reference and high-quality forests. Subsequently, we analyzed the relationship between richness of indicators and patch features recorded in a highly fragmented landscape. Generalized linear models showed that the number of forest indicators was positively related to fragment size and connectivity. Generalized Additive Models showed that the relationship between indicator richness and fragment size was non-linear, with the presence of two thresholds. The number of forest indicators increased until 35–40 ha; above this size the richness remained constant. Fragments above this threshold should be the target of conservation. Furthermore, the relationship between area and number of indicators was less steep in patches smaller than 1–1.5 ha. Patches between these two thresholds can be optimal targets of management actions, as small size increases can greatly improve their value for biodiversity. The identification of two thresholds in the relationship between patch area and indicators suggests an abrupt response to changing landscape features and provide quantitative targets for conservation.     

Modelling the effects of forest landscape dynamics on focal species in Glen Affric, northern Scotland

Current conservation policies promote expansion of semi-naturalwoodland in order to offset effects of past loss and fragmentation.However, conflicts of interest may occur when such expansionwould be at the expense of open habitats considered to haveconservation value in their own right. Landscape modelling ispresented as a method that may prove useful in resolving complexland use issues such as this. An example is given of a modellingsystem that uses forest dynamics modelling, focal species andhabitat network analysis to address landscape change issuesin Glen Affric, a key area for biodiversity conservation innorthern Scotland. The results suggest that a dispersed patternof woodland expansion may offer the best chances of achievinga balance between woodland and open ground in a single catchment.However, there are high levels of uncertainty associated withboth model input data and some of the ecological assumptionswithin the modelling process. Landscape modelling is an emergingdiscipline, and further work is needed to enhance confidencein model outputs.     

Maple Sugar Bush Management and Forest Biodiversity Conservation in Eastern Ontario, Canada

As in many parts of the world, rural and forest-dependent communities in Ontario are struggling with a variety of economic and demographic challenges. Ontario government ministries are seeking to enhance rural sustainable development while at the same time maintaining forest habitat and preventing forest biodiversity decline. Commercial maple sugar bushes, which in Eastern Ontario are typically family owned and operated, have the potential to play an important role in biodiversity conservation and habitat protection, while at the same time contributing to sustainable development. Existing research has shown the social and economic benefits of small scale maple sugar bushes, but room remains for greater study of the environmental impacts, particularly in terms of forest biodiversity. In this study, woodlot management practices on twenty-two sugar bushes in Eastern Ontario were compared against established forest biodiversity conservation guidelines, using information obtained through detailed interviews with operators. Sugar bush operators reported the presence of many important habitats on their properties. The interview results show that many standard sugar bush management practices are consistent with biodiversity conservation principles. Operators were found to be receptive to biodiversity conservation ideals, and could enhance their contribution to the provincial government’s official biodiversity strategy with additional guidance, incentives, and formal planning. The findings suggest that through sound management and planning, small scale commercial sugar bush operations generally can be made environmentally sustainable, and become important components in broader rural development strategies.     

How does forest certification contribute to boreal biodiversity conservation? Standards and outcomes in Sweden and NW Russia

Forest Stewardship Council (FSC) is one of the leading forest certification schemes. While many studies concern political aspects and social outcomes of FSC, little is known about the contribution of certification to biodiversity conservation. In Europe, the Russian Federation and Sweden have the largest areas of FSC-certified forest. We assessed the potential of FSC certification for boreal biodiversity conservation in terms of standard content, and outcomes as habitat area set aside and habitat network functionality. First, we compared the biodiversity conservation indicators at different spatial scales in Swedish and Russian FSC standards. Second, focusing on one large state forest management unit in each country, we compared the areas of formally and voluntarily set aside forests for biodiversity conservation. Third, we evaluated the structural habitat connectivity by applying morphological spatial pattern analysis, and potential functional connectivity by using habitat suitability index modelling for virtual species. The Russian standard included indicators for all spatial scales of biodiversity conservation, from tree and stand to landscape and ecoregions. The Swedish standard focused mainly on stand and tree scales. The area of voluntary set-asides for FSC was similar in Sweden and Russia, while formal protection in the Russian case study was three times higher than in the Swedish one. Swedish set-aside core areas were two orders of magnitude smaller, had much lower structural and potential functional connectivity and were located in a fragmented forestland holding. We conclude that to understand the potential of FSC certification for biodiversity conservation both the standard content, and its implementation on the ground, need to be assessed. We discuss the potential of FSC certification for biodiversity conservation with different levels of ambition. We stress the need for developing rapid assessment tools to evaluate outcomes of FSC for biodiversity conservation on the ground, which could be used by forest managers and FSC-auditors toward adaptive governance and management.     

湛江市林地景观演变及其功能评价研究

利用RS和G IS技术分析了湛江市1996—2007年林地数量和其景观格局的变化,定量评价了其对区域生态系统服务功能的影响。结果表明:在12年中,湛江市林地景观总面积显著增加;斑块破碎程度增大,空间格局变得更为复杂;湛江林地景观的格局演变主要受人类活动的干扰影响,林地生态系统服务功能显著增强的结果与其景观空间格局的变化有密切相关性。最后提出了湛江今后的林地保护和发展策略的建议。     

泰顺县松类纯林改造技术研究

通过套种造林、封山育林、抚育改造等措施,将马尾松纯林改造成针阔混交林,以改变树种结构单一、地力日益衰退、病虫害逐年严重、林地灌木杂草丛生、火灾频繁发生、林分产量低下等状况。结果表明：在松林下套种阔叶树,可不同程度增加单位面积阔叶树数量,形成明显的层次结构,能充分利用林地中的营养空间,马尾松和阀叶树在各自不同层次生长范围...     

森林植物群落多样性与虫害自然控制力的研究进展

讨论了森林植物群落多样性与森林虫害自然控制力间的关系,阐明了森林虫害自然控制力有随森林植物群落多样性的升高而增强的趋势.并认为森林虫害自然控制力的本质是森林植物群落多样性的生态系统功能.初步提出了通过合理地提高森林植物群落多样性来提高森林虫害自然控制力的主张及提高森林虫害自然控制力的几种具体途径,即合理的乔木物种混交;引进和保留乡土的草本、灌木物种;提高生态系统水平的生物多样性;避免营造大面积的人工纯林.     

Oak regeneration using the shelterwood-burn technique: management options and implications for songbird conservation in the southeastern United States

Shelterwood silviculture is commonly used to regenerate oaks in upland stands. However, competition from other species such as tulip-poplar (Liriodendron tulipifera) may deter oak regeneration when these traditional shelterwood techniques are used. The shelterwood-burn technique is a relatively new tool for regenerating oak-dominated stands on some upland sites while simultaneously minimizing undesirable hardwood intrusion with prescribed fire. Once successful oak regeneration has been achieved, three options are available which will result in different vegetative structure and composition within a stand and subsequently different habitats for songbirds. These options are: complete or partial canopy retention, post-harvest prescribed burning and complete canopy removal. Canopy retention, burning and removal treatments will create, respectively, two-age stands that are likely to harbor a diverse mixture of mature forest and early successional species; park-like woodlands with open woodland species; or early-successional habitats with shrubland species. We suggest that shelterwood-burn systems and the management options associated with them offer viable alternatives for managing both songbird and timber resources where oak-dominated stands are the desired goal in upland southeastern sites.     

Long-term approaches to native woodland restoration: Palaeoecological and stakeholder perspectives on Atlantic forests of Northern Europe

The long timeframes involved in woodland regeneration and adaptation introduce considerable uncertainty into management and conservation planning as most ecological datasets span only a small part of ecosystem dynamics. This is a particular concern in vulnerable habitats, such as Atlantic birch-oak woods in north-western Britain, where range edge populations are at risk from herbivory and climate change. This study combines historical palaeoecology and stakeholder observations to assess how multiple perspectives can inform existing models, expectations and goals for Atlantic woodland management. Long-term evidence for changing woodland composition addresses stakeholder uncertainties over the currently restricted distribution of oak, alder and hazel. Oak has remained a secondary component of birch-dominated woods and habitat definitions based on oak are too narrow to ensure sustainability. Birch has survived numerous periods of climatic and biotic adversity and shows the strongest positive response to historic reductions in grazing pressure. This has led to a pulse of regeneration since c. AD 1900, so current restoration efforts are taking place within the strongest period of woodland expansion in the last c. 500 years. Positive and negative cultural legacies are evident and intervention is considered a necessary restoration tool. Managed grazing at key stages of habitat development can support continued recruitment and regeneration. A more flexible and integrated management approach is recommended. Long-term ecology can provide direction and address uncertainties, while ecological and stakeholder evidence provide the detail necessary to develop effective management that incorporates ecosystem perspectives. This can help shape management strategies that balance possible conflicts over perceived short-term ‘damage’ to secure longer-term processes. Learning based on multiple temporal perspectives has the potential to contribute to conservation and restoration planning and practice. These principles are more widely applicable in adaptive management.     

Distribution and composition of carabid beetle (Coleoptera, Carabidae) communities across the plantation forest cycle—Implications for management

If national afforestation targets are met, the proportion of area under plantation forest cover in Ireland will almost double by the year 2030 to 17%, and will consist of mostly non-native trees. There is an urgent and vital need to assess and to maximise the biodiversity potential of these forests. This study compares carabid beetle (Coleoptera, Carabidae) composition and assemblage patterns across different stages of the forest cycle, in addition to intensive grassland habitats, the habitat the plantation forest will most likely be replacing. The clearfell habitat had the highest median species richness, while the grassland habitat had the highest species diversity, but lowest species dominance. Ordination analysis revealed that the species assemblages of all stages of the forest cycle could be clearly separated from the grassland habitat, while differences were also observed between forest stages. Canonical correspondence analysis revealed that the most significant factors influencing carabid community composition were percent cover of ground vegetation and mosses, and also percent soil moisture. Differences in species with varying physical traits and microhabitat preferences were also observed between habitats, with larger, brachypterous species positively associated with increasing canopy cover and smaller macropterous species displaying the opposite pattern. The presence and abundance of forest-associated species increased with increasing plantation age, with a corresponding decrease in open habitat-associated and generalist species. The results of this study suggest that at the landscape scale, a variety of different aged forest stands would maximise the biodiversity potential of the planned afforestation.