查看更多>>摘要：Anthropogenic pressure in tropical montane forests is rapidly increasing, becoming a major threat to these complex ecosystems. Studies have shown that the wide variety of human activities in tropical uplands results in different ecological responses of secondary forests, but basic information on the disturbance impacts and underlying recovery processes is lacking. Here, we compared structural characteristics and tree community composition of old growth forest and secondary forests in a montane region of Sabah, Malaysia, which experienced five different anthropogenic disturbances. We also investigated the use of metrics from spectral trajectories of a Landsat time series (LTS) change detection algorithm (LandTrendr) to identify characteristics of disturbance events and their linkage to the recovery of tree community composition, with field validation. Five LTS metrics-time since the greatest disturbance (TSD), magnitude of disturbance (MD), distance to undisturbed forests (d_UND), recovery indicator (RI), and years to recovery (Y2R) were derived and were related to field-based tree community composition. Our analysis revealed a gradient of recovery patterns in community composition and structural attributes among forest disturbance types, suggesting the importance of community composition as an indicator of forest recovery. Among derived LTS metrics, TSD, MD, d_UND, and Y2R 100% were significantly related with the similarity in community composition. Our results suggest that spectral trajectories from LTS can serve as a useful predictor of community composition change in recovering stands. This approach provides an efficient means for developing systematic conservation strategies for high-elevation regions in the tropics, where human-modified landscapes are expanding.
查看更多>>摘要：Cetaceans play key roles in the world's ecosystems and provide important economic and social benefits. New Zealand's Exclusive Economic Zone is a global biodiversity hotspot for cetaceans and benefits from a system of marine protected areas (MPAs). However, spatial patterns of cetacean biodiversity and their overlap with MPAs have never been assessed.We quantify this overlap by using a comprehensive cetacean at-sea sightings database, high-resolution environmental data layers, and information on ecological and evolutionary characteristics of each species to model spatial patterns of taxonomic, functional, and phylogenetic diversity of cetaceans. We examine areas of congruence among hotspots of richness and uniqueness components of biodiversity and measure the contribution of species to biodiversity.We find that cetacean taxonomic and phylogenetic diversity are spatially mismatched with MPAs, but this is less true for functional diversity. Hotspots of congruence among richness indices are located on the continental shelf break, whereas hotspots of uniqueness indices are located closer to shore on the continental shelf. Seven species have high contributions to biodiversity, with blue whale being the only species being evolutionarily distinct, functionally unique, specialised and globally endangered.Our results underline the potential of multicomponent biodiversity indices, their spatial congruence, and the contribution of species to biodiversity to be used as guides for a strategic placement and expansion of MPAs to protect biodiversity.
查看更多>>摘要：The production and trade of agricultural commodities is a major driver of the loss of tropical biodiversity. In the Mid Zambezi Valley, Zimbabwe, which is home to many emblematic African mammals, cotton production has historically been a major driver of land cover change. The collapse of cotton production in Zimbabwe over the last decade provides a unique opportunity to understand the linkages between the profitability of cotton and land-use changes in this multifunctional landscape. By re-visiting 141 households that had been surveyed in 2007 and combining this panel survey data with a land cover analysis and secondary data, we demonstrate that the decreasing profitability of cotton led to a shift from cotton farming (mean area per farm decreasing from 1.79 +/- 2.05 ha in 2007 to 0.72 +/- 0.90 ha in 2020) to livestock farming (mean number of cattle and goats per farm increasing several-fold between 2007 and 2020), resulting in drastic land cover changes. Indeed, open vegetation (including crops, fallows and grazing areas) expanded from 10 to 20% of the total land cover area between 2007 and 2020. Populations of wildlife species have declined drastically during this period, although this cannot be attributed solely to the observed changes in land cover. However, increasing human-wildlife conflicts are likely to threaten the long-term coexistence of people and wildlife in the area. We argue that commodity crops can be an opportunity for nature conservation, not only a threat, and that conservation needs to support a `living income' for people coexisting with wildlife.
查看更多>>摘要：Psychological ownership, i.e., the sense that an object is "mine/ours", has been adapted from the organisational psychology literature and applied to the environmental sphere to promote individuals' conservation behaviours. However, the concept-"psychological ownership of nature"-requires greater scrutiny to inform its usefulness in human dimensions of conservation. Our paper conceptually explores whether nature could be viable objects for ownership feelings. We theoretically differentiate psychological ownership of nature, with sense/feelings of ownership toward nature being the conceptual core, from other similar concepts like place attachment and connection to nature. We also discuss that psychological ownership of nature may effectively elicit conservation behaviours in individuals with strong anthropocentric worldviews but be less influential for those with high ecocentric beliefs. Psychological ownership of nature might also result in adverse outcomes (e.g., nature exploitation). This paper contributes a conceptual elaboration of psychological ownership of nature and its research agenda in conservation.
查看更多>>摘要：Even though incidental captures in fisheries are one of the major threats to seabirds, bycatch has been difficult to quantify and specific risk areas are rarely identified. The present study evaluates the potential fisheries bycatch effect on two of the most emblematic seabird species wintering off continental Portugal, the critically endangered Balearic Shearwater and Northern Gannet. Information was collected by on-board observers and voluntary logbooks kept by fishing boat captains. Each species' Potential Biological Removal (for the study area) was based on the respective population abundance estimated through aerial surveys. The analysis of bycatch mortality identified the Fixed Gear in the Polyvalent fleet and Purse Seiners as the fisheries with the highest Balearic Shearwater bycatch rate. Longline and Fixed Gear fisheries had the highest Northern Gannet bycatch rate. The Potential Biological Removal thresholds were 41 Balearic Shearwaters per year (CI = 20-83) and 2345 Northern Gannets per year (CI = 2049-2680). The overlap between the predictive species distribution maps and fisheries density maps allowed for a seabird Bycatch Risk Assessment. The higher Balearic Shearwater bycatch risk was obtained for Fixed Gear and Purse Seines and the highest Northern Gannet bycatch risk was obtained for Longline and Fixed Gear fisheries. Bycatch mitigation measures should be applied in fisheries presenting the higher bycatch risks. This study identifies the potential areas where Balearic Shearwater and Northern Gannet bycatch is more likely to occur, including some of the already designated Special Protection Areas where management and conservation measures should urgently be applied.& nbsp;
Froidevaux, Jeremy S. P.Laforge, AlexisLarrieu, LaurentBarbaro, Luc...
8页
查看更多>>摘要：Isolated trees are increasingly recognised as playing a vital role in supporting biodiversity in agricultural landscapes, yet their occurrence has declined substantially in recent decades. Most bats in Europe are tree dependent species that rely on woody elements in order to persist in farmlands. However, isolated trees are rarely considered in conservation programs and landscape planning. Further investigations are therefore urgently required to identify which trees - based on both their intrinsic characteristics and their location in the landscape - are particularly important for bats. We acoustically surveyed 57 isolated trees for bats to determine the relative and interactive effects of size, tree-related microhabitat (TreM) diversity and surrounding landscape context on bat activity. Tall trees with large diameter at breast height and crown area positively influenced the activity of Pipistrellus pipistrellus and small Myotis bats (Myotis spp.) while smaller and thinner trees favoured M. myotis activity. The diversity of TreMs that can be used as roosts had a positive effect on (i) Barbastella barbastellus activity only when trees were relatively close (<50 m) to woody patches, (ii) Pipistrellus nathusii/ kuhlii activity only in the most heterogeneous landscapes, and (iii) Myotis spp. activity only in the most forested environment (>10% within 100 radius scale). The potential benefits of isolated trees for bats result from ecological mechanisms operating at both tree and landscape scales, underlining the crucial need for implementing a multi-scale approach in conservation programs. Maintaining the largest and most TreM-diversified trees located in the most heterogeneous agricultural landscapes will provide the greatest benefits.
查看更多>>摘要：The incidental mortality in trawl fisheries is considered a conservation threat for many seabirds. We simulate management scenarios, combining bird scaring lines (BSL; zero, one and two) and variables describing discards (occurrence, levels, type, and mode), to predict the total seabird collisions with warp cables potentially produced by a demersal trawl fleet operating in a region and season of high seabird abundance. A total of 2067 collisions, including 439 heavy collisions and 53 fatal collisions, were recorded on five trips aboard the Uruguayan trawl fleet. One BSL reduced collisions and heavy collisions by 89%, and the associated mortality by 94%. Best management scenarios in terms of reducing collisions were those without discards, where the models with BSL outperformed the scenarios without BSL. Scenarios with two BSL presented slight improvements, likely caused by the small sample size. Under a scenario without discards, the mortality caused by the entire fleet is likely to be negligible. Given the inability to eliminate discards in most situations, we simulated scenarios of discharge produced in batches with BSL. This could drive mortality to negligible levels. We provide six recommended scenarios (S) ordered by expected reduction in seabird mortality. Fisheries implementing BSL as a single mitigation measure should present a strong reduction in seabird mortality. However, the ability to hold discards on board, at least partially, can drive mortality to negligible levels. This should occur without discards and BSL use (S1), without discards and without BSL (S2), and with batch discharge and BSL use (S3).
查看更多>>摘要：There is a scarcity of studies on how to design conservation organizations to improve biodiversity outcomes. We use information from four conservation organizations (African Parks, Australian Wildlife Conservancy, Mauritian Wildlife Foundation, and Rewilding Argentina) to update and describe an organizational framework for effective conservation organizations. This framework includes (1) clear and shared proactive vision inspired by innovative on-site senior leadership; (2) high contextuality based on shared leadership, on-the-ground administrative autonomy, and practice-based learning; (3) outstanding and well-communicated conservation outcomes; (4) linkages across-scales to access varied types of resources (i.e. political, social and economic); and (5) long-term financial viability. All these attributes form a dynamic and self-reinforcing "virtuous cycle," with each attribute being both cause and effect at different moments in time, though the whole process is jump-started by on-site senior leaders. We believe that our framework can help to identify key questions that will facilitate the design and assessment of private and public conservation organizations towards improved effectiveness.
查看更多>>摘要：Biodiverse communities have been shown to sustain high levels of multifunctionality and thus a loss of species likely negatively impacts ecosystem functions. For most taxa, however, roles of individual species are poorly known. Rare species, often most likely to go extinct, may have unique traits and functional roles. Alternatively, rare species may be functionally redundant, such that their loss would not disrupt ecosystem functions. We quantified the functional role of rare species by using captures of wood-living (saproxylic) beetle species, combined with recent databases of morphological and ecological traits, from three regions in central and northern Europe. Using a rarity index based on species' local abundance, geographic range, and habitat breadth, we used local and regional species removal simulations to examine the contributions of both the rarest and the most common beetle species to three measures of community functional structure: functional richness, functional specialization, and functional originality. Both regionally and locally, all three measures declined more rapidly when rare species were removed than under common (or random) species removal scenarios. These consistent patterns across scales and among forest types give evidence that rare species provide unique functional contributions, and their loss may disproportionately impact ecosystem functions. This implies that conservation measures targeting rare and endangered species, such as preserving intact forests with dead wood and mature trees, can provide broader ecosystem-level benefits. Experimental research linking functional structure to ecosystem processes should be prioritized to increase understanding of the functional consequences of species loss and to develop more effective conservation strategies.
查看更多>>摘要：Areas exhibiting high levels of predations on livestock generate conflicts between humans and large carnivores. Managers generally seek to identify these hotspots, in order to diagnose the causes that lead to hotspot forma-tions and to provide financial or technical support to the involved livestock owners. When locating depredation hotspots, previous studies have not adjusted for livestock availability, making it difficult for managers to discriminate hotspots resulting from underlying livestock clusters from those due to other factors such as environmental factors. We studied hotspots of wolf depredation on sheep in France from the beginning of the natural wolf recolonisation in 1994 up to 2018. For each year, we applied the Ripley's K-function and Ripley's K-inhom to determine the general depredation spatial pattern and the Kulldorff statistic to locate depredation hotspots. We showed that omitting livestock availability in these analyses led to flawed inference about the depredation pattern, and resulted in a substantial number of unidentified hotspots, including pastoral surfaces with low sheep availability. Our methodology provides reliable information for managers to understand the depredation pattern over space and time and to allocate resources.
NSTL
Elsevier