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Assessing habitat loss effects on biodiversity is a major focus of ecological research. The relationship between habitat amount and biodiversity, postulated in the habitat amount hypothesis, is usually assessed at one point in time, which does not account for habitat loss as a temporal process. We examined habitat amount effects at two time periods, 1930s and 2010s, using plant data from three semi-natural habitats: calcareous grassland, heathland and broadleaved woodland, across Dorset, southern England. Woodlands, which changed little in area over the time period, showed minimal effects of habitat amount on species occurrence in both time periods. For grassland and heathland, which had undergone severe losses over the study period, we found the expected positive relationship in the 2010s, but the relationship was negative for these habitats in the 1930s. We explored possible reasons for this result. Total perimeter-to-area ratio (TPAR) showed positive effects in the 1930s for grassland and heathland, suggesting effects of habitat configuration, specifically edge. However, TPAR was highly correlated with habitat amount so this finding is speculative. One possible explanation for the relationships with habitat amount, and the change between the two periods could be the quality of the surrounding matrix. In the 1930s, the landscape was less intensified and was dominated by semi-natural habitats, whereas by the 2010s much had been converted to arable and intensive grasslands. We speculate that species could likely utilise the matrix to a greater degree in the 1930s compared with the 2010s when the matrix was more hostile, thereby decreasing the importance of habitat amount in the 1930s compared with the 2010s. These findings have important implications for conservation, as they show the importance of context (i.e. matrix quality) in determining the relationship between habitat amount and biodiversity.

Human beings are an active component of every terrestrial ecosystem on Earth. Although our local impact on the evolution of these ecosystems has been undeniable and extensively documented, it remains unclear precisely how our activities are altering them, in part because ecosystems are dynamic systems structured by complex, non-linear feedback processes and cascading effects. We argue that it is only by studying human–environment interactions over timescales that greatly exceed the lifespan of any individual human (i.e., the deep past or longue durée), we can hope to fully understand such processes and their implications. In this article, we identify some of the key challenges faced in integrating long-term datasets with those of other areas of sustainability science, and suggest some useful ways forward. Specifically, we (a) highlight the potential of the historical sciences for sustainability science, (b) stress the need to integrate theoretical frameworks wherein humans are seen as inherently entangled with the environment, and (c) propose formal computational modelling as the ideal platform to overcome the challenges of transdisciplinary work across large, and multiple, geographical and temporal scales. Our goal is to provide a manifesto for an integrated scientific approach to the study of socio-ecological systems over the long term., Policy Analysis

We used a spatially explicit model of forest dynamics, supported by empirical field data and socioeconomic data, to examine the impacts of human disturbances on a protected forest landscape in Kyrgyzstan. Local use of 27 fruit and nut species was recorded and modeled. Results indicated that in the presence of fuelwood cutting with or without grazing, species of high socioeconomic importance such as Juglans regia, Malus spp., and Armeniaca vulgaris were largely eliminated from the landscape after 50-150 yr. In the absence of disturbance or in the presence of grazing only, decline of these species occurred at a much lower rate, owing to competitive interactions between tree species. This suggests that the current intensity of fuelwood harvesting is not sustainable. Conversely, current grazing intensities were found to have relatively little impact on forest structure and composition, and could potentially play a positive role in supporting regeneration of tree species. These results indicate that both positive and negative impacts on biodiversity can arise from human populations living within a protected area. Potentially, these could be reconciled through the development of participatory approaches to conservation management within this reserve, to ensure the maintenance of its high conservation value while meeting human needs.

Information on the dispersal ability of flightless insect species associated with woodlands is severely lacking. Therefore, a study was conducted examining the dispersal ability of wood cricket (Nemobius sylvestris) juveniles (nymphs) and adults in a wooded landscape on the Isle of Wight, UK, to further our understanding of the ecology and management of this and other flightless insects. A series of experiments were conducted where nymphs and adults were released and observed at a range of spatial-temporal scales within different habitat environments. The results of this investigation indicated no difference in the dispersal ability of wood cricket nymphs and adults. However, adult females moved less than adult males. Adult males were found to spread twice as fast as females, and males were found capable of traversing up to 55 m away from woodland habitat through semi-natural and grazed grassland. Additionally, rates of population spread of both wood cricket nymphs and adults (males and females) were found to be accurately described by the inverse-power function, predicting only few individuals dispersing over time. Together this indicates that overall colonization success and rate of population spread, being female dependent, is likely to be low for this species. Wood crickets were found to live in and able to move along mature woodland edges directly bordering agricultural land. This indicates that conservation initiatives focusing on creating woodland corridors and developing woodland habitat networks have the potential to facilitate the spread and population viability of wood crickets, if the woodland edges are given enough time to develop. However, long-term monitoring is needed to evaluate the overall effectiveness of such approaches.

Information on the dispersal ability of invertebrate species associated with woodland habitats is severely lacking. Therefore, a study was conducted examining the movement patterns of wood cricket (Nemobius sylvestris) (Orthoptera: Gryllidae) on the Isle of Wight, UK. Juvenile (i.e. nymphs) and adult wood crickets were released and observed over time within different ground surface substrates. Their movement paths were recorded and subsequently analysed using random walk models. Nymphs were found to move more slowly than adults did; and, when given a choice, both nymphs and adults showed a preference for moving through or over leaf litter compared to bare soil or grass. A correlated random walk (CRW) model accurately described the movement pattern of adult wood crickets through leaf litter, indicating a level of directional persistence in their movements. The estimated population spread through leaf litter for adults was 17.9 cm min−1. Movements of nymphs through leaf litter could not accurately be described by a random walk model, showing a change in their movement pattern over time from directed to more random movements. The estimated population spread through leaf litter for nymphs was 10.1 cm min−1. The results indicate that wood cricket adults can be considered as more powerful dispersers than nymphs; however, further analysis of how the insects move through natural heterogeneous environments at a range of spatio-temporal scales needs to be performed to provide a complete understanding of the dispersal ability of the species.

Dispersal is an important process determining species spread and survival in fragmented landscapes. However, information on the dispersal ability of woodland-associated invertebrate species is severely lacking. A study was conducted examining the ability of wood cricket (Nemobius sylvestris) (Orthoptera: Gryllidae) to cross small watercourses and to orientate themselves towards habitat edges. A series of experiments were conducted where juvenile (i.e. nymph) and adult wood crickets were released and observed over time. The results of this investigation indicated that (i) nymphs and adults were equally able to swim across a small (≤35 cm) watercourse; and (ii) adult wood cricket were able to positively orientate themselves towards a mature woodland edge at a visual angle of ≥19°, when less than 50 m away. Together, this investigation suggests that these traits likely facilitate the ability of this species to disperse within fragmented wooded landscapes, however, further study is needed to strengthen the significance of these findings for this and similar species.

Spatial modelling approaches are increasingly being used to direct forest management and conservation planning at the landscape scale. A popular approach is the use of buffer-radius methods, which create buffers around distinct forest habitat patches to assess habitat connectivity within anthropogenic landscapes. However, the effectiveness and sensitivity of such methods have rarely been evaluated. In this study, Euclidean and least-cost buffer-radius approaches were used to predict functional ecological networks within the wooded landscape of the Isle of Wight (UK). To parameterize the models, a combination of empirical evidence and expert knowledge was used relating to the dispersal ability of a model species, the wood cricket (Nemobius sylvestris Bosc.). Three scenarios were developed to assess the influence of increasing the amount of spatial and species-specific input data on the model outcomes. This revealed that the level of habitat fragmentation for the model species is likely to be underestimated when few empirical data are available. Furthermore, the least-cost buffer approach outperformed simple Euclidean buffer in predicting presence and absence for the model species. Sensitivity analyses on model performance revealed high sensitivity of the models to variation in buffer distance (i.e. maximum dispersal distance) and permeability of common landscape features such as roads, watercourses, grassland and semi-natural habitat. This indicates that when data are lacking with which to parameterize buffer-radius models, the model outcomes need to be interpreted with caution. This study also showed that if sufficient empirical data are available, least-cost buffer approaches have the potential to be a valuable tool to assist forest managers in making informed decisions. However, least-cost approaches should always be used as an indicative rather than prescriptive management tool to support forest landscape conservation and planning.

The potential benefits of implementing biodiversity conservation at a landscape-scale are increasingly recognised, with the aim of developing a more dynamic landscape, with greater resilience to environmental change. The integration of environmental, economic and social factors is essential for effective evaluation of such a landscape-scale approach and this recognition of multi-functionality is essential in incorporating an ecosystems approach into policy making.

1. A systematic review was conducted to gather empirical evidence on movement rates of invertebrates associated with woodland. 2. Eight scientific literature databases were systematically searched for relevant studies on invertebrates associated with woodland habitat. 3. Twenty-five studies were identified that met the search selection criteria, which provided estimates of movement rate for 30 invertebrate species associated with woodland habitat. These 30 species represented insect species only, including 17 carabid (ground) beetle, eight butterfly, two bark beetle, two ant, and one moth species. From 2000 to 2008, only six studies were identified, indicating a current lack of dispersal-related studies for woodland invertebrates. 4. A meta-analysis of studies on ground-dwelling species indicated that carabid beetle species that were strongly associated with woodland habitat were found to move more slowly than more generalist species (median: 2.1 m day−1 vs. 11.0 m day−1). Furthermore, for carabid beetles it was found that body size was positively correlated with movement rate. 5. The lack of field measurements of movement and dispersal ability for all but a tiny minority of woodland invertebrates indicates a substantial knowledge gap that should be addressed by future research, which might usefully test whether the patterns identified for carabid beetles are generally applicable.

Little information is available regarding the landscape ecology of woodland invertebrate species with limited dispersal ability. An investigation was therefore conducted within woodland fragments in an agricultural landscape for the flightless wood cricket (Nemobius sylvestris) on the Isle of Wight, UK. The current pattern of distribution of the species, established during a field survey, was related to measures of habitat availability and habitat isolation/fragmentation. Results revealed that wood cricket populations were patchily distributed and mainly found in relatively large mature woodland fragments situated closely (<50 m) to another occupied site. Although the occurrence of wood cricket was related to fragment area, isolation, habitat availability and woodland age, a logistic regression model revealed that presence of the species was most accurately predicted by fragment isolation and area alone. These results highlight the vulnerability of relatively immobile woodland invertebrate species, such as wood cricket, to the impacts of habitat loss and fragmentation.

In the UK, wood cricket (Nemobius sylvestris) is a ‘Species of Conservation Concern’, being restricted to only three areas in southern England. Little information is available on the specific habitat requirements of this species. In 2006, a field investigation within three woodlands on the Isle of Wight was undertaken to identify its habitat preferences. Factors positively influencing wood cricket presence within woodlands included the presence of a well-developed leaf litter layer, relatively low ground vegetation cover and height, low canopy cover and relatively short distances between individual populations. Regression models identified the degree of isolation and variables describing vegetation structure as the main predictors for wood cricket presence within woodland fragments. The results of this study indicate the preference of wood cricket for open wooded edges. Conservation efforts for this species should focus on continuation of regular management activities aimed at providing permanent open edge habitat within woodlands, to maintain viable populations.

Different buffer-radius modelling approaches were used to assess habitat connectivity for the woodland-specialist invertebrate species, wood cricket (Nemobius sylvestris), on the Isle of Wight, UK. The results highlight the demand for detailed information in terms of species and land cover data, to use modelling tools effectively in conservation planning.

Spatial modelling approaches are increasingly used to design and direct management and conservation plans at the landscape scale. One of the main developments is buffer-radius approaches that use information on the dispersal ability of species to create buffers around distinct habitat patches to assess habitat connectivity within the landscape. In this study, Euclidean and least-cost buffers were used to predict functional ecological networks for wood cricket (Nemobius sylvestris) within the wooded landscape of the Isle of Wight, UK. Compared to the Euclidean buffer approach, the least-cost method revealed a higher number of functional networks indicating a high level of habitat fragmentation for wood cricket and similar woodland invertebrate species. Recent habitat network development increased network connectivity in 3 out of 4 cases. The results further highlight the demand for detailed information, both in terms of species specific and in terms of land cover data, for using least-cost modelling tools effectively in conservation planning.

Although sustainable forest management (SFM) has been widely adopted as a policy and management goal, high rates of forest loss and degradation are still occurring in many areas. Human activities such as logging, livestock husbandry, crop cultivation, infrastructural development, and use of fire are causing widespread loss of biodiversity, restricting progress toward SFM. In such situations, there is an urgent need for tools that can provide an integrated assessment of human impacts on forest biodiversity and that can support decision making related to forest use. This paper summarizes the experience gained by an international collaborative research effort spanning more than a decade, focusing on the tropical montane forests of Mexico and the temperate rain forests of southern South America, both of which are global conservation priorities. The lessons learned from this research are identified, specifically in relation to developing an integrated modeling framework for achieving SFM. Experience has highlighted a number of challenges that need to be overcome in such areas, including the lack of information regarding ecological processes and species characteristics and a lack of forest inventory data, which hinders model parameterization. Quantitative models are poorly developed for some ecological phenomena, such as edge effects and genetic diversity, limiting model integration. Establishment of participatory approaches to forest management is difficult, as a supportive institutional and policy environment is often lacking. However, experience to date suggests that the modeling toolkit approach suggested by Sturvetant et al. (2008) could be of value in such areas. Suggestions are made regarding desirable elements of such a toolkit to support participatory-research approaches in domains characterized by high uncertainty, including Bayesian Belief Networks, spatial multi-criteria analysis, and scenario planning.

In this paper we aim to investigate the problems and potentialities of species distribution modeling (SDM) as a tool for conservation planning and policy development and implementation in tropical regions. We reviewed 123 studies published between 1995 and 2007 in five of the leading journals in ecology and conservation, and examined two tropical case studies in which distribution modeling is currently being applied to support conservation planning. We also analyzed the characteristics of data typically used for fitting models within the specific context of modeling tree species distribution in Central America. The results showed that methodological papers outnumbered reports of SDMs being used in an applied context for setting conservation priorities, particularly in the tropics. Most applications of SDMs were in temperate regions and biased towards certain organisms such as mammals and birds. Studies from tropical regions were less likely to be validated than those from temperate regions. Unpublished data from two major tropical case studies showed that those species that are most in need of conservation actions, namely those that are the rarest or most threatened, are those for which SDM is least likely to be useful. We found that only 15% of the tree species of conservation concern in Central America could be reliably modelled using data from a substantial source (Missouri Botanical Garden VAST database). Lack of data limits model validation in tropical areas, further restricting the value of SDMs. We concluded that SDMs have a great potential to support biodiversity conservation in the tropics, by supporting the development of conservation strategies and plans, identifying knowledge gaps, and providing a tool to examine the potential impacts of environmental change. However, for this potential to be fully realized, problems of data quality and availability need to be overcome. Weaknesses in current biological datasets need to be systematically addressed, by inc

There is an increasing awareness in Chile of the need to improve the representation of the country's forest types in the national network of protected areas, and to reduce the impacts of the native forest conversion to other land uses. One promising strategy is to use the principles of systematic conservation planning to identify important areas for the conservation of biodiversity. In this chapter we use information on the vulnerability of native forest to threatening processes and information on the distribution of forest types to systematically determine priorities for biodiversity conservation in the temperate forest region of south-central Chile. We find that the existing reserve network covers approximately 12 of the study region, and that only 53 of the area of native forest estimated to be present before European settlement remained in 1997. Temperate forest is now largely restricted to the upper elevations of the Andean and coastal ranges, within a matrix of pasture, agriculture and plantations. We develop a model of the conversion of native forest to plantations and predict conversion to be more likely in warm and low rainfall areas that are close to towns and roads and on red clay and mixed alluvial soils. We argue that the priority areas for conservation should be currently unprotected areas that are vulnerable to plantation conversion and that, if lost or degraded, will result in conservation targets being compromised. We find the Evergreen forest type to be a priority for conservation owing to its lack of representation in the existing reserve network and the degree to which it has been cleared. By focusing our conservation efforts on areas with the greatest conservation value and the highest likelihood of losing significant portions of this value, we will be able to achieve maximum impact for conservation investments in south-central Chile. © CAB International 2007.

Sustainable use of species-rich moist forests needs an understanding of forest dynamics and the response of the forest to wood harvesting events. This chapter studies natural forest dynamics, explores the productivity of native managed forests and quantifies the ecological impacts of different management strategies. The process-based forest growth model FORMIND is applied to study natural forest succession and to assess long-term ecological implications of fuelwood extraction for tropical montane cloud forest in central Veracruz, Mexico, as well as to compare potential harvesting strategies for Valdivian temperate rainforest in northern Chiloe Island, Chile, regarding forest productivity and ecological consequences. Simulation results show that both forest types have a relatively high potential for wood production. As wood extraction increases, the forest structure becomes simplified because large old trees disappear from the forest. The species composition shifts to tree species that are favoured by the respective harvesting strategy. The overall ecological impact increases linearly with the amount of extracted wood. Simulation results allow management strategies to be defined that balance conservation and production objectives, promote the regeneration of desired tree species, or minimize shifts in the species composition of the forest. Process-based forest models enhance our understanding of the dynamics of species-rich moist forests and are indispensable tools to assess long-term implications of anthropogenic impacts on forest ecosystems. They can thereby contribute to the conservation and sustainable use of native forests outside protected areas.