Lasway, Julius, VNjovu, Henry K.Kinabo, Neema R.Eardley, Connal...
9页
查看更多>>摘要：Livestock grazing is widespread and increasing in the African grasslands, with largely unknown consequences for bee pollinators. Here we assessed the direct and indirect impacts of livestock grazing intensity on bee assemblages in East African grasslands and tested if the effect of grazing intensity on bee assemblages depends on temperature. We collected data on 24 study sites representing three different levels of livestock grazing intensity in northern Tanzania. Ordinary linear models and path analysis were used to test the effect of grazing and temperature on floral resources and bee diversity. Non-metric multidimensional scaling (NMDS) and permutational MANOVA were used to analyze changes in bee community composition and bee-visited plant community with grazing intensity and temperature. We found that moderate livestock grazing slightly increased bee species richness while high grazing intensity led to a strong decline. Further, bee species richness was highest at moderate temperatures and significantly lower in colder and very hot environments. Path analysis results showed that the effect of livestock grazing and environmental temperature on bee species richness is mediated by a positive effect of moderate grazing on floral resource richness. Livestock grazing led to a significant change in the species composition of bee communities, this effect was stronger in environments with very high temperatures. Our study reveals that bee communities of the African savannah zone may benefit from low levels of livestock grazing as this proliferates the growth of flowering plant species. However, livestock grazing at high intensity will cause significant species losses and turnover of bee species communities; effects which may increase with climatic warming.
查看更多>>摘要：During the last century, the progressive substitution of landraces with modern, high yielding varieties, led to a dramatic reduction of in situ conserved crop diversity in Europe. Nowadays there is limited and scattered information on where landraces are cultivated. To fill this gap and lay the groundwork for a regional landrace in situ conservation strategy, information on more than 19,335 geo-referenced landrace cultivation sites were collated from 14 European countries. According to collected data, landraces of 141 herbaceous and 48 tree species are cultivated across Europe: Italy (107 species), Greece (93), Portugal (45) and Spain (44) hold the highest numbers. Common bean, onion, tomato, potato and apple are the species of main interest in the covered countries. As from collected data, about 19.8% of landrace cultivation sites are in protected areas of the Natura 2000 network. We also got evidence that 16.7% and 19.3% of conservation varieties of agricultural species and vegetables are currently cultivated, respectively. Results of the GIS analysis allowed the identification of 1261 cells (25 km x 25 km) including all the cultivation sites, distributed across all European biogeographical regions. Data of this study constitute the largest ever produced database of in situ-maintained landraces and the first attempt to create an inventory for the entire Europe. The availability of such resource will serve for better planning of actions and development of policies to protect landraces and foster their use.
查看更多>>摘要：There is a growing awareness of the need to integrate climate and biodiversity policies. As forests play an important role in mitigating biodiversity loss and climate change, numerous countries have established goals and are managing their forests to achieve them. However, forest management measures and land prioritization may differ depending on the target chosen, leading to conflicts. This research aims to seek optimized national afforestation plans in the Republic of Korea by assessing trade-offs between plant biodiversity persistence and carbon stocks. To this end, afforestation scenarios were spatially established based on the national forest man-agement plans, with a target of 5800 ha expansion by 2022. Generalized Dissimilarity Modeling (GDM) and Global Forest Model (G4M) were applied to the selected afforestable regions to obtain scenarios that maximize biodiversity and carbon, respectively. Furthermore, another afforestation scenario that considers both objectives equally, was proposed using spatial simulated annealing (SSA) optimization algorithm to mitigate trade-offs. The constructed scenarios were compared, both spatially and quantitatively. As a result, the maximization scenarios were found to have few overlapping areas, with both scenarios resulting in ~50% trade-offs. These findings reveal that there is no universal solution and different management strategies are needed to enhance biodiversity persistence and carbon stocks. Thus, to strike a balance among the various goals, forest management requires a compromise solution to minimize trade-offs. Our national-scale assessment can help to guide future planning of national forest management with the consideration of the joint goals of biodiversity and carbon enhancement.
查看更多>>摘要：Network analysis is a highly flexible statistical framework with a diversity of uses across both ecology and other fields of study. Recent developments in ecological-based network methods have created active research interest in areas such as animal behaviour, community ecology, and landscape connectivity. With the increasing availability of genetic data from wild populations, network analysis has become a viable and important method for the study of both between and within population genetics. However, to date there is a lack of cohesion in the methodology and terminology used in genetic networks, making it difficult for researchers to undertake network analysis or follow field-specific best practices. Here, we conducted a literature review of studies that use geneticbased networks to describe and analyse population structure, genetic connectivity, dispersal, and to understand individual level of genetic relatedness. We categorise studies as population-level networks and individual-based genetic networks, based on their node definition, and discuss the commonalities and differences between these approaches. Additionally, we present an overview of the current methods and software available for the construction and analysis of genetic networks. Lastly, we discuss how genetic networks can effectively contribute to the field of conservation biology, with particular focus on defining population structure/units, understanding genetic connectivity, dispersal, and detecting source/sink dynamics, as well as addressing how genetic networks can aid studies of individual or familial fitness and understanding population inbreeding and bottlenecks.
Soofi, MahmoodQashqaei, Ali T.Trei, Jan-NiklasShokri, Shirko...
12页
查看更多>>摘要：Poaching is a global driver of wildlife population decline, including inside protected areas (PAs). Reducing poaching requires an understanding of its cryptic drivers and accurately quantifying poaching scales and intensity. There is little quantification of how poaching is affected by law enforcement intensity (e.g., ranger stations) versus economic factors (e.g., unemployment), while simultaneously accounting for imperfect detection. Using extensive data of poaching events (i.e., seizures) and censuses of nine ungulate species across the PAs and unprotected lands of Iran from 2010 to 2018, we developed a single-visit hierarchical (N-mixture) model to accurately estimate annual poaching of Iranian ungulates and to differentiate between social and ecological effects on annual poaching intensity. We found that poaching detectability increased with numbers of ranger stations. A recent surge in poaching (2013-2018) coincides with rising unemployment rate. We estimated that 19,727 ungulates (95% confidence interval 11,178-36,195) were poached across the country during 2010-2018. Poaching intensity was positively related to unemployment rate, road density, and ungulate abundance. Our simulations demonstrated that the Poisson and Negative binomial N-mixture models had adequate performance when the conditions of S acute accent olymos et al. (2012) were satisfied, in particular, when at least one covariate is unique to both the detection and abundance parts of the model. Overall, we suggest that single-visit models offer unique insights into understanding the link between poaching intensity, economic conditions , law enforcement in large-scale landscapes while accounting for imperfect detection of poaching events.
查看更多>>摘要：Biodiversity offsetting is the widely studied last step of the mitigation hierarchy. Despite numerous studies and the methodological development completed for biodiversity calculations, the human aspect remains unsolved. Biodiversity conservation is typically governed at national or state levels, but the harm caused to biodiversity as well as people occurs locally. In biodiversity offsetting, biodiversity values can be relocated far from the original area, but relocating the values people hold regarding their nearby nature may not be possible. Acknowledging the local people's hopes and values may further complicate biodiversity offsetting, therefore it emphasises even more the need to avoid and reduce the negative impacts, i.e. the earlier steps of mitigation hierarchy. In this review we present the current understanding of the social impacts on biodiversity offsetting based on scientific literature. We identified a clear research gap in relation to the opportunities local people have to participate in decision-making processes related to biodiversity offsetting. Biodiversity offsetting can cause the displacement of local people and negatively affect their livelihood, but there is little literature on that aspect of the offsetting procedure. In addition, biodiversity offsetting can cause loss of livelihood or living area in the Global South while impacts in the Global North are often more indirect. Ways to compensate the losses to local people vary from land use rights in other areas to economic compensation. It is unclear if there are offsetting protocols which are acceptable both socially and in terms of biodiversity.
查看更多>>摘要：Reliable and efficient techniques are urgently needed to monitor elasmobranch populations that face increasing threats worldwide. Aerial video-surveys provide precise and verifiable observations for the rapid assessment of species distribution and abundance in coral reefs, but the manual processing of videos is a major bottleneck for timely conservation applications. In this study, we applied deep learning for the automated detection and mapping of vulnerable eagle rays from aerial videos. A light aircraft dedicated to touristic flights allowed us to collect 42 h of aerial video footage over a shallow coral lagoon in New Caledonia (Southwest Pacific). We extracted the videos at a rate of one image per second before annotating them, yielding 314 images with eagle rays. We then trained a convolutional neural network with 80% of the eagle ray images and evaluated its ac-curacy on the remaining 20% (independent data sets). Our deep learning model detected 92% of the annotated eagle rays in a diversity of habitats and acquisition conditions across the studied coral lagoon. Our study offers a potential breakthrough for the monitoring of ray populations in coral reef ecosystems by providing a fast and accurate alternative to the manual processing of aerial videos. Our deep learning approach can be extended to the detection of other elasmobranchs and applied to systematic aerial surveys to not only detect individuals but also estimate species density in coral reef habitats.
Cordeiro, Carlos L. O.Geldmann, Jonas D.Jonas, HarryGaiarsa, Marilia Palumbo...
7页
查看更多>>摘要：Area-based conservation measures, including protected areas (PA) and other effective area-based conservation measures (OECM), play an important role in biodiversity conservation. In the Brazilian Amazon, even though Conservation Units and Indigenous Lands have been shown to reduce deforestation, few studies have addressed Quilombola Territories, and none of the above-mentioned areas were evaluated according to their role in promoting native vegetation regrowth. Here, we used a matching analysis to show that Brazilian Amazon Indigenous Lands, Quilombola Territories, and two types of protected areas (Conservation Units of Restrict Use and Sustainable Use) contribute to reduced native vegetation conversion, when compared to their control areas. Indigenous Lands and Conservation Units of Restrict Use lost respectively 17 and five times less native vegetation cover than their unprotected control areas, between the years of 2005-2012. Similarly, Quilombola Territories had native vegetation loss rates 5.6 times lower than in matched controls. Importantly, our results demonstrate for the first time that between 2012 and 2017 Indigenous Lands and Quilombola Territories contributed two and three times more to native vegetation regrowth - a critical process for safeguarding biodiversity in many, if not all, parts of the world. Our results underscore the importance of areas beyond the formal protected areas system in conserving biodiversity and promoting forest regrowth.
查看更多>>摘要：The introduction of non-native pine plantations and subsequent pine invasion are increasingly affecting native and high conservation value forests in the Southern Hemisphere. Pine invasion changes forest fire regimes, even in protected areas. However, most research evaluating the impact on fuel of this invasion on South American habitats has focused on steppe ecosystems; few studies have investigated whether pine-dominated areas are more flammable than native forests, how invasion age influences flammability, and whether areas dominated by mature pines from invasion and plantation have a similar impact on fuel. Here, we analyzed the fine fuel traits of the understory of different-aged post-fire invasions, plantations of Pinus radiata, and nearby native vegetation in a forest reserve (Patagonia, Argentina). Community composition shifts towards pine-dominated areas increased fire risk by affecting the quantity, distribution, composition, and condition (live or dead) of the fuel. Flamma-bility levels increased with time since invasion. The oldest invasion had a higher load of the most flammable fuel than the adult plantation. Our results show that community composition shifts towards pine-dominated areas can increase fire risk by producing more pyrophytic habitats, and suggest that early removal of post-fire invasions can prevent increased fire risk on a landscape scale. Our results highlight the importance of considering the intrinsic characteristics of an invasion context when evaluating the impact of non-native species, and the need to be cautious when extrapolating the impacts of plantations to invasions.
NSTL
Elsevier