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1.
Over 80% of Atlantic Forest remnants are <50 ha and protected areas are embedded in a matrix dominated by human activities, undermining the long‐term persistence of carnivores. The ocelot (Leopardus pardalis) is an opportunistic species, but little is known about its tolerance to habitat alterations and the influence of other species on its occupancy in Atlantic Forest remnants. We used camera traps to assess ocelot occupancy in protected areas of Atlantic Forest in southeastern Brazil. We found a positive correlation between the occupancy of ocelots and top predators (jaguars, Panthera onca, and pumas, Puma concolor), and a weaker negative effect between the number of domestic dogs (Canis familiaris) detected and ocelot occupancy. Ocelot detection was higher at sites with more eucalyptus, suggesting that ocelots frequently use these areas. Better‐protected areas surrounded by permeable matrices may be critical to the persistence of ocelots in the fragmented Atlantic Forest.  相似文献   

2.
The jaguar (Panthera onca) plays an important role in maintaining biodiversity and ecological processes. We evaluated the status of a jaguar population in one of the last stronghold habitats for its conservation in the Atlantic Forest, the Rio Doce State Park (RDSP). We used a random survey design from 2016/17 to estimate jaguar abundance and density as well as its occupancy and detection probabilities in the entire Park''s area. To monitor for temporal fluctuations in density and abundance, we used a systematic survey design in the southern portion of the Park where jaguars were more recorded when using the random approach. We then conducted two surveys in 2017/18 and 2020. Our 2016/17 random survey revealed that jaguar density (0.11 ± SE 0.28 individuals/100 km2) was the lowest obtained for the species across the Atlantic Forest. We noticed that jaguar density increased three times from 2017/18 (0.55 ± SE 0.45 individuals/100 km2) to 2020 (1.61 ± SE 0.6 individuals/100 km2). Jaguar occupancy and detection probability were 0.40 and 0.08, respectively. The low jaguar occupancy probability was positively associated with smaller distances from lakes and records of potential prey. The detection probability was positively associated with prey detection, the rainy season, and smaller distances from lakes. Our work contributes to a growing awareness of the potential conservation value of a protected area in a human‐dominated landscape as one of the last strongholds for jaguars across the Atlantic Forest.  相似文献   

3.
Conservation of large carnivores such as leopards requires large and interconnected habitats. Despite the wide geographic range of the leopard globally, only 17% of their habitat is within protected areas. Leopards are widely distributed in Nepal, but their population status and occupancy are poorly understood. We carried out the sign‐based leopard occupancy survey across the entire Chure range (~19,000 km2) to understand the habitat occupancy along with the covariates affecting their occupancy. Leopard signs were obtained from in 70 out of 223 grids surveyed, with a naïve leopard occupancy of 0.31. The model‐averaged leopard occupancy was estimated to be 0.5732 (SE 0.0082) with a replication‐level detection probability of 0.2554 (SE 0.1142). The top model shows the additive effect of wild boar, ruggedness, presence of livestock, and human population density positively affecting the leopard occupancy. The detection probability of leopard was higher outside the protected areas, less in the high NDVI (normalized difference vegetation index) areas, and higher in the areas with livestock presence. The presence of wild boar was strong predictor of leopard occupancy followed by the presence of livestock, ruggedness, and human population density. Leopard occupancy was higher in west Chure (0.70 ± SE 0.047) having five protected areas compared with east Chure (0.46 ± SE 0.043) with no protected areas. Protected areas and prey species had positive influence on leopard occupancy in west Chure range. Similarly in the east Chure, the leopard occupancy increased with prey, NDVI, and terrain ruggedness. Enhanced law enforcement and mass awareness activities are necessary to reduce poaching/killing of wild ungulates and leopards in the Chure range to increase leopard occupancy. In addition, maintaining the sufficient natural prey base can contribute to minimize the livestock depredation and hence decrease the human–leopard conflict in the Chure range.  相似文献   

4.
Mammals have experienced a massive decline in their populations and geographic ranges worldwide. The sloth bear, Melursus ursinus (Shaw, 1791), is one of many species facing conservation threats. Despite being endangered in Nepal, decades of inattention to the situation have hindered their conservation and management. We assessed the distribution and patterns of habitat use by sloth bears in Chitwan National Park (CNP), Nepal. We conducted sign surveys from March to June, 2020, in 4 × 4 km grids (n = 45). We collected detection/non‐detection data along a 4‐km trail that was divided into 20 continuous segments of 200 m each. We obtained environmental, ecological, and anthropogenic covariates to understand determinants of sloth bear habitat occupancy. The data were analyzed using the single‐species single‐season occupancy method, with a spatially correlated detection. Using repeated observations, these models accounted for the imperfect detectability of the species to provide robust estimates of habitat occupancy. The model‐averaged occupancy estimate for the sloth bear was 69% and the detection probability was 0.25. The probability of habitat occupancy by sloth bears increased with the presence of termites and fruits and in rugged, dry, open, undisturbed habitats. Our results indicate that the sloth bear is elusive, functionally unique, and widespread in CNP. Future conservation interventions and action plans aimed at sloth bear management must adequately consider their habitat requirements.  相似文献   

5.
Forest fragmentation and habitat loss are detrimental to top carnivores, such as jaguars (Panthera onca) and pumas (Puma concolor), but effects on mesocarnivores, such as ocelots (Leopardus pardalis), are less clear. Ocelots need native forests, but also might benefit from the local extirpation of larger cats such as pumas and jaguars through mesopredator release. We used a standardized camera trap protocol to assess ocelot populations in six protected areas of the Atlantic forest in southeastern Brazil where over 80% of forest remnants are < 50 ha. We tested whether variation in ocelot abundance could be explained by reserve size, forest cover, number of free-ranging domestic dogs and presence of top predators. Ocelot abundance was positively correlated with reserve size and the presence of top predators (jaguar and pumas) and negatively correlated with the number of dogs. We also found higher detection probabilities in less forested areas as compared to larger, intact forests. We suspect that smaller home ranges and higher movement rates in smaller, more degraded areas increased detection. Our data do not support the hypothesis of mesopredator release. Rather, our findings indicate that ocelots respond negatively to habitat loss, and thrive in large protected areas inhabited by top predators.  相似文献   

6.
Once widespread throughout the tropical forests of the Indian Subcontinent, the sloth bears have suffered a rapid range collapse and local extirpations in the recent decades. A significant portion of their current distribution range is situated outside of the protected areas (PAs). These unprotected sloth bear populations are under tremendous human pressures, but little is known about the patterns and determinants of their occurrence in most of these regions. The situation is more prevalent in Nepal where virtually no systematic information is available for sloth bears living outside of the PAs. We undertook a spatially replicated sign survey‐based single‐season occupancy study intending to overcome this information gap for the sloth bear populations residing in the Trijuga forest of southeast Nepal. Sloth bear sign detection histories and field‐based covariates data were collected between 2 October and 3 December 2020 at the 74 randomly chosen 4‐km2 grid cells. From our results, the model‐averaged site use probability (ψ ± SE) was estimated to be 0.432 ± 0.039, which is a 13% increase from the naïve estimate (0.297) not accounting for imperfect detections of sloth bear signs. The presence of termite mound and the distance to the nearest water source were the most important variables affecting the habitat use probability of sloth bears. The average site‐level detectability (p ± SE) of sloth bear signs was estimated to be 0.195 ± 0.003 and was significantly determined by the index of human disturbances. We recommend considering the importance of fine‐scale ecological and anthropogenic factors in predicting the sloth bear‐habitat relationships across their range in the Churia habitat of Nepal, and more specifically in the unprotected areas.  相似文献   

7.
Due to rapid urbanization, logging, and agricultural expansion, forest fragmentation is negatively affecting native wildlife populations throughout the tropics. This study examined the effects of landscape and habitat characteristics on the lesser mouse‐deer, Tragulus kanchil, populations in Peninsular Malaysia. We conducted camera‐trap survey at 315 sampling points located within 8 forest reserves. An assessment of site‐level and landscape variables was conducted at each sampling point. Our study provides critical ecological information for managing and conserving understudied populations of T. kanchil. We found that the detection of T. kanchil was attributed to forest fragmentation in which forest patches had four times greater detection of T. kanchil than continuous forest. The detection of T. kanchil was nearly three times higher in peat swamp forest compared to lowland dipterocarp forests. Surprisingly, the detection of T. kanchil was higher in logged forests (logging ceased at least 30 years ago) than unlogged forests. The detection of T. kanchil increased with the presence of trees, particularly those with DBH of 5 cm to 45 cm, canopy cover, number of saplings and palms, number of dead fallen trees, and distance from nearest roads. However, detection decreased with a greater number of trees with DBH greater than 45 cm and higher elevations, and greater detections where creeping bamboo was abundant. We recommend that conservation stakeholders take the necessary steps (e.g., eradicating poaching, habitat degradation, and further deforestation) to support the conservation of mouse‐deer species and its natural habitats.  相似文献   

8.
Complete documentation on the status of mammals is indispensable for appropriate conservation measures in protected areas. However, there is inadequate information on mammalian resources in the ecosystem of Gibe Sheleko National Park (GSNP). Thus, the study aimed to assess species diversity, abundance, and habitat association of medium‐ and large‐sized mammals in GSNP. We stratified the study area into five dominant habitat types, namely dense forest, wooded grassland, grassland, riverine forest, and farmland habitat types based on land cover and vegetation structures and further employed stratified random sampling technique across each habitat type. The sample transects covered 20% of the study area. Transect width ranged from 50 m to 400 m based on vegetation cover and visibility of mammals. The main data were collected via direct observation. Data were analyzed via chi‐square test and species diversity indexes. We recorded the total of 20 mammals species'' those belong to 10 families of which 8 species were large‐sized and 12 species medium‐sized mammals. There were two IUCN vulnerable species, namely Hippopotamus amphibious and Panthera pardus, and two globally near‐threatened species, particularly Litocranius walleri and Caracal caracal in the study area. Dense forest held the highest species diversity of medium‐ and large‐sized mammals (H′ = 2.28) with the highest evenness index (J = 0.84). Riverine forest had the least diversity with uneven population distribution. Papio anubis was the most abundance species, whereas Caracal caracal was the least abundant in the study area. GSNP is home for threatened and spectacular mammals species''; hence, an appropriate conservation measure is mandatory to keep existing mammals species''.  相似文献   

9.
As a result of extensive data collection efforts over the last 20–30 years, there is quite a good understanding of the large‐scale geographic distribution and range limits of African great apes. However, as human activities increasingly fragment great ape spatial distribution, a better understanding of what constitutes suitable great ape habitat is needed to inform conservation and resource extraction management. Chimpanzees (Pan troglodytes troglodytes) and gorillas (Gorilla gorilla gorilla) inhabit the Lobéké National Park and its surrounding forest management units (FMUs) in South‐East Cameroon. Both park and neighboring forestry concessions require reliable evidence on key factors driving great ape distribution for their management plans, yet this information is largely missing and incomplete. This study aimed at mapping great ape habitat suitability in the area and at identifying the most influential predictors among three predictor categories, including landscape predictors (dense forest, swampy forest, distance to water bodies, and topography), human disturbance predictors (hunting, deforestation, distance to roads, and population density), and bioclimatic predictor (annual precipitation). We found that about 63% of highly to moderately suitable chimpanzee habitat occurred within the Lobéké National Park, while only 8.4% of similar habitat conditions occurred within FMUs. For gorillas, highly and moderately suitable habitats occurred within the Lobéké National Park and its surrounding FMUs (82.6% and 65.5%, respectively). Key determinants of suitable chimpanzee habitat were hunting pressure and dense forest, with species occurrence probability optimal at relatively lower hunting rates and at relatively high‐dense forest areas. Key determinants of suitable gorilla habitat were hunting pressure, dense forests, swampy forests, and slope, with species occurrence probability optimal at relatively high‐dense and swampy forest areas and at areas with mild slopes. Our findings show differential response of the two ape species to forestry activities in the study area, thus aligning with previous studies.  相似文献   

10.
  1. Thermal imaging technology is a developing field in wildlife management. Most thermal imaging work in wildlife science has been limited to larger ungulates and surface‐dwelling mammals. Little work has been undertaken on the use of thermal imagers to detect fossorial animals and/or their burrows. Survey methods such as white‐light spotlighting can fail to detect the presence of burrows (and therefore the animals within), particularly in areas where vegetation obscures burrows. Thermal imagers offer an opportunity to detect the radiant heat from these burrows, and therefore the presence of the animal, particularly in vegetated areas. Thermal imaging technology has become increasingly available through the provision of smaller, more cost‐effective units. Their integration with drone technology provides opportunities for researchers and land managers to utilize this technology in their research/management practices.
  2. We investigated the ability of both consumer (<AUD$20,000) and professional imagers (>AUD$65,000) mounted on drones to detect rabbit burrows (warrens) and entrances in the landscape as compared to visual assessment.
  3. Thermal imagery and visual inspection detected active rabbit warrens when vegetation was scarce. The presence of vegetation was a significant factor in detecting entrances (p < .001, α = 0.05). The consumer imager did not detect as many warren entrances as either the professional imager or visual inspection (p = .009, α = 0.05). Active warren entrances obscured by vegetation could not be accurately identified on exported imagery from the consumer imager and several false‐positive detections occurred when reviewing this footage.
  4. We suggest that the exportable frame rate (Hz) was the key factor in image quality and subsequent false‐positive detections. This feature should be considered when selecting imagers and suggest that a minimum export rate of 30 Hz is required. Thermal imagers are a useful additional tool to aid in identification of entrances for active warrens and professional imagers detected more warrens and entrances than either consumer imagers or visual inspection.
  相似文献   

11.
The EU''s Biodiversity Strategy for 2030 makes great promises about halting the decline of biodiversity but it offers little in terms of implementation. Subject Categories: S&S: Economics & Business, Ecology, S&S: Ethics

Earth is teeming with a stunning variety of life forms. Despite hundreds of years of exploration and taxonomic research, and with 1.2 million species classified, we still have no clear picture of the real extent of global biodiversity, with estimates ranging from 3 to 100 million species. A highly quoted—although not universally accepted—study predicted some 8.7 million species, of which about 2.2 million are marine (Mora et al, 2011). Although nearly any niche on the surface of Earth has been colonized by life, species richness is all but evenly distributed. A large share of the known species is concentrated in relatively small areas, especially in the tropics (Fig 1). Ultimately, it is the network of the interactions among life forms and the physical environment that make up the global ecosystem we call biosphere and that supports life itself.Open in a separate windowFigure 1Biological hotspots of the worldA total of 36 currently recognized hotspots make up < 3% of the planet''s land area but harbor half of the world''s endemic plant species and 42% of all terrestrial vertebrates. Overall, hotspots have lost more than 80% of their original extension. Credit: Richard J. Weller, Claire Hoch, and Chieh Huang, 2017, Atlas for the End of the World, http://atlas‐for‐the‐end‐of‐the‐world.com/. Reproduced with permission.Driven by a range of complex and interwoven causes–such as changes in land and sea use, habitat destruction, overexploitation of organisms, climate change, pollution, and invasive species–biodiversity is declining at an alarming pace. A report by the Intergovernmental Science‐Policy Platform on Biodiversity and Ecosystem Services (IPBES) issued a clear warning: “An average of around 25 per cent of species in assessed animal and plant groups are threatened, suggesting that around 1 million species already face extinction, many within decades, unless action is taken to reduce the intensity of drivers of biodiversity loss. Without such action, there will be a further acceleration in the global rate of species extinction, which is already at least tens to hundreds of times higher than it has averaged over the past 10 million years” (IPBES, 2019) (Fig 2). Although focused on a smaller set of organisms, a more recent assessment by WWF has reached similar conclusions. Their Living Planet Index, that tracks the abundance of thousands of populations of mammals, birds, fish, reptiles, and amphibians around the world, shows a stark decline in monitored populations (WWF, 2020). As expected, the trend of biodiversity decline is not homogeneous with tropical areas paying a disproportionately high price, mostly because of unrestrained deforestation and exploitation of natural resources.Open in a separate windowFigure 2The global, rapid decline of biodiversity(A) Percentage of species threatened with extinction in taxonomic groups that have been assessed comprehensively, or through a “sampled” approach, or for which selected subsets have been assessed by the IUCN Red List of Threatened Species. Groups are ordered according to the best estimate, assuming that data‐deficient species are as threatened as non‐data deficient species. (B) Extinctions since 1500 for vertebrate groups. (C) Red List Index of species survival for taxonomic groups that have been assessed for the IUCN Red List at least twice. A value of 1 is equivalent to all species being categorized as Least Concern; a value of zero is equivalent to all species being classified as Extinct. Data for all panels from www.iucnredlist.org. Reproduced from (IPBES, 2019), with permission.
Driven by a range of complex and interwoven causes […] biodiversity is declining at an alarming pace.
Against this dire background, the EU has drafted a Biodiversity Strategy 2030, an ambitious framework aimed to tackling the key reasons behind biodiversity loss. The plan hinges around a few main elements, such as the establishment of protected areas for at least 30% of Europe''s lands and seas (Fig 3); a significant increase of biodiversity‐rich landscape features on agricultural land by establishing buffer zones like hedges and fallow fields; halting and reversing the decline of pollinators; and planting 3 billion trees by 2030 (https://ec.europa.eu/info/strategy/priorities‐2019‐2024/european‐green‐deal/actions‐being‐taken‐eu/eu‐biodiversity‐strategy‐2030_en). The budget for implementing these measures was set at €20 billion per year.Open in a separate windowFigure 3Natura 2000, the EU''s network of protected areasIn 2019, 18% of land in the EU was protected as Natura 2000, with the lowest share of protected land in Denmark (8%) and the highest in Slovenia (38%). In 2019, the largest national network of terrestrial Natura 2000 sites was located in Spain, covering 138,111 km2, followed by France (70,875 km2) and Poland (61,168 km2). Reproduced from Eurostat: https://ec.europa.eu/eurostat/statistics‐explained/index.php?title=Main_Page “Nature is vital for our physical and mental wellbeing, it filters our air and water, it regulates the climate and it pollinates our crops. But we are acting as if it didn''t matter, and losing it at an unprecedented rate”, said Virginijus Sinkevičius, Commissioner for the Environment, Oceans and Fisheries, at the press launch of the new EU action (https://ec.europa.eu/commission/presscorner/detail/en/ip_20_884). “This new Biodiversity Strategy builds on what has worked in the past, and adds new tools that will set us on a path to true sustainability, with benefits for all. The EU''s aim is to protect and restore nature, to contribute to economic recovery from the current crisis, and to lead the way for an ambitious global framework to protect biodiversity around the planet”.Environmental groups and other stakeholders have welcomed the EU''s pledge in principle. “This is a unique opportunity to shape a new society in harmony with nature”, applauded Wetlands International. “We must not forget that the biodiversity and climate crisis is a much bigger and persistent challenge for humanity than COVID‐19”, (https://europe.wetlands.org/news/welcoming‐the‐eu‐biodiversity‐strategy‐for‐2030/). EuroNatur, a foundation focused on conservation, stated that the goals set out by the new strategy provide a strong basis for improving the state of nature in the EU (www.euronatur.org).Alongside the voices of praise, however, many have expressed concerns that the strategy could turn into a little more than a wish list. “The big issue of the strategy is that while setting a goal for financial funds, the EU does not specify where the money is supposed to come from. It only says it should include ‘EU funds and national and private funding’”, commented the European Wilderness Society, an environmental advocacy non‐profit organization headquartered in Tamsweg, Austria. “Goals are important, but do not create change without an organized and sustainable implementation. It''s a good and ambitious document, but what is also obvious is the lack of strategy of how to implement it, and a lack of discussion of why previous documents of this type failed” (https://wilderness‐society.org/ambitious‐eu‐biodiversity‐strategy‐2030/).
Alongside the voices of praise, however, many have expressed concerns that the strategy could turn into a little more than a wish list.
The Institute for European Environmental Policy (IEEP) is on the same page. The sustainability think‐tank based in Brussels and London noted that the outgoing EU 2020 biodiversity strategy showed major implementation problems, especially because of lack of engagement at national level and of ad hoc legislation supporting the meeting of key targets. Therefore, “[it] can be argued that a legally binding approach to the biodiversity governance framework is urgently needed unless Member States and other key stakeholders can show greater intrinsic ownership to deliver on agreed objectives”, (https://ieep.eu/news/first‐impressions‐of‐the‐eu‐biodiversity‐strategy‐to‐2030). In addition, IEEP remarked that money is an issue, since the €20 billion figure appears more as an estimate than a certified obligation.“The intentions of the Commission are good and the strategy contains a number of measures and targets that can really make a difference. However, implementation depends critically on the member states and experiences with the Common Agricultural Policy the past decade or so have taught us that many of them are more interested in short‐term economic objectives than in safeguarding the natural wealth of their country for future generations”, commented David Kleijn, an ecologist and nature conservation expert at the Wageningen University, the Netherlands. “I think it is important that we now have an ambitious Biodiversity Strategy but at the same time I have little hope that we will be able to achieve its objectives”.
I think it is important that we now have an ambitious Biodiversity Strategy but at the same time I have little hope that we will be able to achieve its objectives.
There is further criticism against specific measures, such as the proposal of planting 3 billion trees. “To have lots of trees planted in an area does not necessarily translate into an increase of biodiversity. Biodiverse ecosystems are the result of million years of complex multi‐species interactions and evolutionary processes, which are not as easy to restore”, explained plant ecologist Susana Gómez‐González, from the University of Cádiz, Spain. Planting a large number of trees is a too simplistic approach for saving European forests from the combined effects of excessive anthropic pressure and climate change, and could even have detrimental effects (see Box 1). More emphasis should be placed instead in reducing tree harvesting in sensitive areas and in promoting natural forest renewal processes (Gómez‐González et al, 2020). “For a biodiversity strategy, increasing the number of trees, or even increasing the forest area, should not be an objective; priority should be given to the conservation and restoration of natural ecosystems, forests and non‐forests”, Gómez‐González said.In other cases, it could be difficult, if not impossible, to reach some of the goals because of lack of information. For example, one of the roadmap''s targets is to restore at least 25,000 km of Europe''s rivers back to free‐flowing state. However, the number of barriers dispersed along European rivers will probably prevent even getting close to the mark. An international research team has collected detailed information on existing instream barriers for 147 rivers in 36 European countries, coming up with the impressive figure of over 1.2 million obstacles that inevitably impact on river ecosystems, affecting the transport and dispersion of aquatic organisms, nutrients, and sediments (Belletti et al, 2020). Existing inventories mainly focused on dams and other large barriers, while, in fact, a large number of artificial structures are much smaller, such like weirs, locks, ramps, and fords. As a result, river fragmentation has been largely underestimated, and the models used to plan flow restoration might be seriously flawed. “To avoid ‘death by a thousand cuts’, a paradigm shift is necessary: to recognize that although large dams may draw most of the attention, it is the small barriers that collectively do most of the damage. Small is not beautiful”, concluded the authors (Belletti et al, 2020).

Box 1: Why many trees don''t (always) make a forestForests are cathedrals of biodiversity. They host by far the largest number of species on land, which provide food and essential resources for hundreds of millions of people worldwide. However, forests are disappearing and degrading at an alarming pace. The loss of these crucial ecosystems has given new impulses to a variety of projects aimed at stopping this devastation and possibly reversing the trend.Once it is gone, can you rebuild a forest? Many believe the answer is yes, and the obvious solution is to plant trees. Several countries have thus launched massive tree‐planting programs, notably India and Ethiopia, where 350 million trees have been planted in single day (https://www.unenvironment.org/news‐and‐stories/story/ethiopia‐plants‐over‐350‐million‐trees‐day‐setting‐new‐world‐record). The World Economic Forum has set up its own One Trillion Tree initiative (https://www.1t.org/) “to conserve, restore, and grow one trillion trees by 2030”. Launched in January last year at Davos, 1t.org was conceived as a platform for governments, companies and NGOs/civil society groups to support the UN Decade on Ecosystem Restoration (2021–2030). The initiative has been christened by renowned naturalist Jane Goodall, who commented: “1t.org offers innovative technologies which will serve to connect tens of thousands of small and large groups around the world that are engaged in tree planting and forest restoration”, (https://www.weforum.org/agenda/2020/01/one‐trillion‐trees‐world‐economic‐forum‐launches‐plan‐to‐help‐nature‐and‐the‐climate/).However, things are way more complicated than they appear: large‐scale tree planting schemes are rarely a viable solution and can even be harmful. “[A] large body of literature shows that even the best planned restoration projects rarely fully recover the biodiversity of intact forests, owing to a lack of sources of forest‐dependent flora and fauna in deforested landscapes, as well as degraded abiotic conditions resulting from anthropogenic activities”, commented Karen Holl from the University of Caliornia, Santa Cruz, and Pedro Brancalion from the University of São Paulo (Holl & Brancalion, 2020). A common problem of tree plantations, for example, is the low survival rate of seedlings, mostly because the wrong tree species are selected and due to poor maintenance after planting. Moreover, grasslands and savannas, which are often targeted for establishing new forests, are themselves treasure troves of biodiversity. Ending indiscriminate deforestation, improving the protection of existing forests, and promoting their restoration would therefore be a more efficient strategy to preserve biodiversity in the shorter term. If tree planting is indeed necessary, it should be well planned by selecting the right areas for reforestation, using suitable tree species that can maximize biodiversity, and involving local populations to maintain the plantations, Holl and Brancalion argue (Holl & Brancalion, 2020).

…even the best planned restoration projects rarely fully recover the biodiversity of intact forests, owing to a lack of sources of forest‐dependent flora and fauna in deforested landscapes…
The health of soil, where a high proportion of biodiversity is hosted, is another problem the new strategy should address in a more focused manner. “In my opinion, the EU Biodiversity Strategy is already a leap forward in terms of policy interest in soils in general and in soil biodiversity in particular. Compared with other nations/regions of the world, Europe is by far in the forefront regarding this issue”, commented Carlos António Guerra at the German Centre for Integrative Biodiversity Research (iDiv) in Leipzig, Germany, and Co‐leader of the Global Soil Biodiversity Observation Network (https://geobon.org/bons/thematic‐bon/soil‐bon/). “Nevertheless, the connection between soil biodiversity and ecological functions needs further commitments. Soils allow for horizontal integration of several policy agendas, from climate to agriculture and, very importantly, nature conservation. This is not explicit in the EU Biodiversity Strategy in regard to soils”. It remains to be seen if EU restoration plan will emphasize soil biodiversity, or consider it as a mere side effect of other initiatives, Guerra added. “A soil nature conservation plan should be proposed”, he said. “Only such a plan, that implies that current and future protected areas have to consider, describe and protect their soil biodiversity would make a significant push to help protect such a valuable resource”.More generally, research shows that the current paradigm of protection must be shifted to prevent further losses to biodiversity. In fact, an analysis of LIFE projects—a cornerstone of EU nature protection—found that conservation efforts are extremely polarized and strongly taxonomically biased (Mammola et al, 2020). From 1992 to 2018, investment in vertebrates was sixfold higher than that for invertebrates, with birds and mammals alone accounting for 72% of the targeted species and 75% of the total budget. In relative terms, investment per species for vertebrates has been 468 times higher than for invertebrates (Fig 4). There is no sound scientific reasoning behind this uneven conservation attention, but just popularity. “[T]he species covered by a greater number of LIFE projects were also those which attracted the most interest online, suggesting that conservation in the EU is largely driven by species charisma, rather than objective features”, the researchers wrote (Mammola et al, 2020).Open in a separate windowFigure 4Taxonomic bias in EU fauna protection effortsBreakdown of the number of projects (A) and budget allocation (B) across main animal groups covered by the LIFE projects (n = 835). (C) The most covered 30 species of vertebrates (out of 410) and invertebrates (out of 78) in the LIFE projects analyzed (n = 835). The vertical bar represents monetary investment and the blue scatter line the number of LIFE projects devoted to each species. Reproduced from (Mammola et al, 2020), with permission.  相似文献   

12.

In the supporting information of the article, the authors noticed that there was an error in Movie EV1. The right panel (SARS‐CoV‐2 + IFITM1) showed the same PI channel data (red) as the middle panel (SARS‐CoV‐2). This mistake occurred during the assembly of the merged movie file and does not change the interpretation of the data. A corrected version of the movie is herewith updated.  相似文献   

13.

Recent cryo‐EM‐based models reveal how the ER membrane protein complex may accomplish insertion of protein transmembrane domains with limited hydrophobicity.

Insertion of strongly hydrophobic TMDs into the ER membrane is mediated by the Sec61 complex for co‐translational insertion and the GET complex for post‐translational insertion of tail‐anchors (Volkmar & Christianson, 2020). By contrast, the EMC inserts TMDs of limited hydrophobicity, frequently located at the N‐ or C‐termini of proteins, and is involved in biogenesis of multi‐spanning membrane proteins (Volkmar & Christianson, 2020).The EMC is highly conserved (Wideman, 2015). In vertebrates, ten subunits have been identified (EMC1‐10), two of which, EMC8 and EMC9, are homologous and the result of a vertebrate‐specific gene duplication (Wideman, 2015). In Saccharomyces cerevisiae, EMC8 has been lost (Wideman, 2015). Only EMC3 displays clear homology to other membrane protein insertases, the Oxa1 family (Wideman, 2015; Volkmar & Christianson, 2020). This family includes YidC, which inserts TMDs into the bacterial cytoplasmic membrane, usually in cooperation with the Sec61‐homologous SecYEG channel (Volkmar & Christianson, 2020). Their association, along with the SecDF ancillary complex, forms a holo‐translocon capable of protein secretion and TMD insertion, with striking similarities to the EMC complex (Martin et al, 2019).Recent work by Pleiner et al (2020) presented a 3.4 Å cryo‐EM structure of the human EMC purified via a GFP‐tag on EMC2 and incorporated into a phospholipid nanodisc. The complex is formed by nine proteins (EMC1‐8, EMC10) (Pleiner et al, 2020). EMC8 and EMC9 are structurally similar, and their association with EMC2 is mutually exclusive (O''Donnell et al, 2020). Of the 12 TMDs, nine constitute the pseudosymmetric central ordered core, with a basket‐shaped cytosolic vestibule formed primarily by alpha‐helices of the EMC3 and EMC6 TMDs and cytosolic EMC2 (Fig 1A; Pleiner et al, 2020). The L‐shaped lumenal domain of the EMC consists mostly of beta‐sheets (Fig 1A; Pleiner et al, 2020), flanked by a conspicuous and conserved amphipathic alpha‐helix of EMC1 sealing the vestibule at the interface between the membrane and the ER lumen, together with another smaller amphipathic helix contributed by EMC3 (Fig 1A; Pleiner et al, 2020). In the ER lumen, the two 8‐bladed propellers of EMC1 contact six of the eight other subunits and stabilize the entire complex (Fig 1A; Pleiner et al, 2020). Beta‐sandwiches of EMC7 and EMC10 are anchored to the EMC1 lumenal domain (Fig 1A; Pleiner et al, 2020). In the cytosol, the tetratricopeptide repeat (TPR) spiral of EMC2 forms a cup underneath the partially hydrophilic vestibule in the membrane between the TMDs of EMC3 and EMC6, bridging the cytosolic ends of TMDs of EMC1, 3 and 5 (Fig 1A; Pleiner et al, 2020). Cytosolic EMC8 is bound to the opposite face of EMC2 (Fig 1A).Open in a separate windowFigure 1Comparison of the structures of human and yeast EMC(A) Cryo‐EM 3D map of the human (emdb‐21929) and yeast (emdb‐21587) EMC, showing front and back views with individual subunits coloured. Membrane position, obtained from the OPM database, is shown by grey discs. (B) Close‐up view of the EMC cavity formed by EMC3 and EMC6. Left, shown in a hydrophobicity surface pattern. Right, surface representation overlapped with the TMDs of EMC3 and EMC6. EMC4, flexible and with a gate function at the substrate‐binding place, is shown in pink in the yeast representation. EMC4 is not visible at the atomic EMC human structure, although is observed as a weak density at the human model, accompanied by TMs of EMC7 and EMC10 (Pleiner et al, 2020). (C) The yeast EMC following > 5 µs of CG‐MD simulation. The protein is shown as surface and coloured as per Pleiner et al (2020). The computed densities of waters and phospholipid tails and phosphates are shown as blue, yellow and lime green densities, sliced to bisect the cavity for clarity. Right, inset of the EMC cavity. Methods: CG‐MD simulations were built using PDB 6WB9 in a solvated symmetric POPC/POPE/cholesterol membrane and run in the Martini forcefield as described in Martin et al (2019). 3 µs unrestrained simulations were run, followed by 2.5 µs backbone restrained simulation for density calculation, done using VolMap in VMD (Humphrey et al, 1996).The 3.0 Å cryo‐EM structure of the yeast EMC presented by Bai and colleagues shows a very similar overall organization (Bai et al, 2020). Here, purification was via a 3xFLAG‐tag on EMC5, and the structure of the 8‐subunit complex (without EMC8/9) was visualized in detergent solution (Bai et al, 2020). The yeast complex has twelve TMDs like the human EMC, but unlike the human structure, EMC4 in yeast has three TMDs that are clearly visible (Bai et al, 2020). They are angled in the membrane pointing away from the complex at the cytosolic end (Fig 1A), and Bai et al (2020) propose that TMDs of EMC4, EMC3 and EMC6 form a substrate‐binding pocket similar to that of YidC. As in the human EMC, there are two amphipathic helices (EMC1 and EMC3) at the membrane/lumen interface (Fig 1A; Bai et al, 2020). In the ER lumen, yeast EMC1 only has one 8‐bladed beta‐propeller, to which the beta‐sandwiches of EMC7 and EMC10 are anchored (Fig 1A; Bai et al, 2020). In the cytosol, EMC2 bridges EMC3, 4 and 5, and its TPR repeats form a cup underneath the vestibule similar to human EMC2 (Fig 1A; Bai et al, 2020).The authors propose that insertion of a partially hydrophilic TMD by the yeast EMC is mechanistically similar to insertion by bacterial YidC (Bai et al, 2020). Yeast EMC is proposed to bind substrate between TMD2 of EMC3 and TMD2 of EMC4 in a pocket with polar and positively charged amino acids at either end and hydrophobic amino acids in the centre (Fig 1B; Bai et al, 2020). Much has been made of a conserved positive region within the EMC complex here, present in an equivalent position also in YidC (Kumazaki et al, 2014): It is claimed to be important for the incorporation of more‐hydrophilic TMDs and perhaps responsible for the “positive‐inside” orientation rule (von Heijne, 1992). Yeast and human EMC3 contain a specific R31 and R26 residue, respectively, conserved also in YidC and important for function of the EMC, as well as for YidC in Gram‐positive, but interestingly not Gram‐negative, bacteria (Chen et al, 2014; Pleiner et al, 2020; Bai et al, 2020). Another interesting feature, also conserved with YidC, is the flexibility of the TMDs flanking the substrate‐binding pocket, critical for EMC entry of substrates (Bai et al, 2020).In the human EMC, methionine residues in a cytosolic loop of EMC3 act as a substrate bait (Pleiner et al, 2020). Polar and charged residues within the substrate‐binding groove guide the lumenal domain across the membrane, facilitated by local membrane thinning (Pleiner et al, 2020; Fig 1B). The positive charges within the substrate‐binding site exclude signal peptides and enforce the “positive‐inside rule” (von Heijne, 1992; Pleiner et al, 2020). Flexible TMDs of EMC4, EMC7 and EMC10 forming a “lateral gate” of the substrate‐binding groove allow sampling of the bilayer by the substrate TMD (Pleiner et al, 2020). As the shortened TMDs of EMC3 and EMC6 cannot stably bind the substrate TMD, they favour its release into the bilayer (Pleiner et al, 2020). The EMC1 beta‐propeller(s) may recruit additional protein maturation factors in the ER lumen (Pleiner et al, 2020; Bai et al, 2020) or bind the Sec61 channel to allow cooperation between the two insertases (Bai et al, 2020).Arguably, the most interesting feature of the EMC complex is the location of a large interior cavity with distinctive hydrophilic character, which likely aids TMD insertion (Fig 1B). We ran a coarse‐grained molecular dynamics (CG‐MD) simulation of the yeast EMC structure, which highlights a profound perturbation of the phospholipid bilayer in the EMC interior cavity (Fig 1C). Here, a deep gorge forms in the cytoplasmic leaflet of the bilayer, allowing the cavity to become flooded with water (Fig 1C). Note the location of the lipid head groups here (lime green), which presumably define the site of amphipathic TMD insertion. The incursion of phospholipids into the centre of the EMC complex is a feature shared by the bacterial holo‐translocon (Martin et al, 2019) and perhaps by all membrane protein insertases. The shape and character of the EMC cavity presumably dictate its predisposition for less hydrophobic TMDs; it would be interesting to see whether the cavities of different insertases are similarly tailored to suit their substrates.  相似文献   

14.
  1. A central theme for conservation is understanding how animals differentially use, and are affected by change in, the landscapes they inhabit. However, it has been challenging to develop conservation schemes for habitat‐specific behaviors.
  2. Here we use behavioral change point analysis to identify behavioral states of golden eagles (Aquila chrysaetos) in the Sonoran and Mojave Deserts of the southwestern United States, and we identify, for each behavioral state, conservation‐relevant habitat associations.
  3. We modeled behavior using 186,859 GPS points from 48 eagles and identified 2,851 distinct segments comprising four behavioral states. Altitude above ground level (AGL) best differentiated behavioral states, with two clusters of short‐distance movement behaviors characterized by low AGL (state 1 AGL = 14 m (median); state 2 AGL = 11 m) and two associated with longer‐distance movement behaviors and characterized by higher AGL (state 3 AGL = 108 m; state 4 AGL = 450 m).
  4. Behaviors such as perching and low‐altitude hunting were associated with short‐distance movements in updraft‐poor environments, at higher elevations, and over steeper and more north‐facing terrain. In contrast, medium‐distance movements such as hunting and transiting were over gentle and south‐facing slopes. Long‐distance transiting occurred over the desert habitats that generate the best updraft.
  5. This information can guide management of this species, and our approach provides a template for behavior‐specific habitat associations for other species of management concern.
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15.
The competitive relationship and coexistence pattern among close related species have long been one of the hot issues in ecological research. Interspecies interactions can exert important influences on the local distribution of rare species. Black muntjac Muntiacus crinifrons is an endemic species to eastern China, currently restricted to limited regions. In contrast, Chinese muntjac Muntiacus reevesi is the most common and widespread deer in southern China. Both species co‐occur in southern Anhui and western Zhejiang Province. Little is known about the interaction of these two sympatric‐related species. In this study, to investigate the site use determinants and co‐occurrence pattern of the two sympatric muntjac species, we conducted a camera trap survey across about 250 km2 in mountainous area of southern Anhui Province, China. We adopted a multistep approach to incorporate habitat preferences while modeling occupancy and detection. We found that the two species did not separate along elevation gradient (range from 400 m to 1,400 m) as described in previous studies. Results of single‐species occupancy models indicated that elevation had positive effects on the site use of both species, while slope had an opposite influence on their site use. Positive effects of elevation on the site use implied that both species try to avoid human interference at low elevations. Significant negative effect of slope on the site use of black muntjac suggested that the species prefer habitat with gentle slope and avoided steep. Co‐occurrence models and species interaction factors provided evidence that the two muntjac species had an independent occupancy (ψ BM CM = ψ BM cm, SIF = 1) and exhibited a positive species interaction in detection probability (p BM < r BM CM). Combined with the results of previous studies, we suggested that it was fine differentiation in microhabitats and food resources utilization rather spatial or temporal segregation that allowed the two species co‐occurrence. The site use determinants revealed in our study would be useful for the habitat conservation and restoration for the rare black muntjac, and the co‐occurrence pattern of the two sympatric muntjac species could provide useful information for deep understanding of the coexistence mechanism among forest‐dwelling ungulates.  相似文献   

16.
  1. The young leaves are the main source of nucleic acids for population genetic studies in palm‐trees; however, the access to this tissue may be limited by specific features of each species. Using root tissues as an alternative source of nucleic acids could facilitate the sampling in large populations.
  2. This study tests root tissue viability as an alternative nucleic acid source (root versus. leaf) and explores different protocols (tissue storage and DNA extraction methods) to obtain high‐quality DNA samples.
  3. The results showed no significant differences in DNA concentration (603.7 vs. 599.1 ng/μl) and quality ratios (A260/280:2.1 vs. 1.9, and A260/230:2.1 vs. 2.0) for the comparisons of tissue source (leaf vs. root) and DNA extraction method (manual vs. kit). For tissue storage method, DNA concentration was significantly higher for root tissues stored in 70% and 90% alcohol solutions (692.8 and 822.6 ng/μl, respectively) versus those obtained from leaf tissue (603.7 ng/μl); however, for the quality parameters, no differences were found.
  4. Results showed the effective potential of using root tissue as an alternative source for nucleic acids, which could facilitate population sampling of palm‐tree species for future studies, and this methodological alternative could be applied to other plant systems with similar sampling challenges.
​  相似文献   

17.
  1. Community scientists have illustrated rapid declines of several aphidophagous lady beetle (Coccinellidae) species. These declines coincide with the establishment of alien coccinellids. We established the Buckeye Lady Beetle Blitz program to measure the seasonal occupancy of coccinellids within gardens across a wide range of landscape contexts. Following the Habitat Compression Hypothesis, we predicted that gardens within agricultural landscapes would be alien‐dominated, whereas captures of natives would be higher within landscapes encompassing a high concentration of natural habitat.
  2. Within the state of Ohio, USA, community scientists collected lady beetles for a 7‐day period across 4 years in June and August using yellow sticky card traps. All identifications were verified by professional scientists and beetles were classified by three traits: status (alien or native), mean body length, and primary diet. We compared the relative abundance and diversity of coccinellids seasonally and determined if the distribution of beetles by size, status, and diet was related to landscape features.
  3. Alien species dominated the aphidophagous fauna. Native aphidophagous coccinellid abundance was positively correlated with forest habitat while alien species were more common when gardens were embedded within agricultural landscapes. Urbanization was negatively associated with both aphidophagous alien and native coccinellids.
  4. Synthesis and Applications: Our census of native coccinellid species within residential gardens—a widespread and understudied habitat—was enabled by volunteers. These data will serve as an important baseline to track future changes within coccinellid communities within this region. We found that native coccinellid species richness and native aphidophagous coccinellid abundance in gardens were positively associated with forest habitat at a landscape scale of 2 km. However, our understanding of when and why (overwintering, summer foraging, or both) forest habitats are important remains unclear. Our findings highlight the need to understand how declining aphidophagous native species utilize forest habitats as a conservation priority.
  相似文献   

18.
Crop raiding is a major form of human‐wildlife interaction mainly in the ecotone areas of human‐modified natural landscapes. The aim of this study was to examine the spatial pattern of crop raiding and the resultant impacts on how farmers perceive forests at different distances from Yayu Coffee Forest Biosphere Reserve which is located in southwest Ethiopia. For this, thirty transects (each 1 km long) were laid out at 200 m interval parallel to forest edges: ten transects close to forest (<0.5 km), ten at intermediate (0.5–1 km), and ten transects were taken far from forest (>1 km). Along each transect, 2–6 households were randomly selected and interviewed using semistructured questionnaire. The perception of the respondents on forests at different distances from forest edges was analyzed using Pearson''s Chi‐square test. The variation in the amount of damage among these three locations was tested using one‐way ANOVA. Four wild large mammals including olive baboon, vervet monkey, bush pigs, and crested porcupine were identified as top crop raiders in the area. The frequencies of occurrence of crop raiders decreased with increasing distance from forest edges. Similarly, the amount of damage in maize fields was higher close to forests when compared with that of either at intermediate or far from forest edges (p < .001). Eighty‐one percent of the households living close to the forests perceive that forest is a threat to their survival. Overall, our results imply that strategies need to be sought in order to minimize the socio‐ecological impacts of crop raiders mainly in locations close to forest edges.  相似文献   

19.
Nucleosomes are dynamic entities with wide‐ranging compositional variations. Human histone variants H2A.B and H2A.Z.2.2 play critical roles in multiple biological processes by forming unstable nucleosomes and open chromatin structures, but how H2A.B and H2A.Z.2.2 confer these dynamic features to nucleosomes remains unclear. Here, we report cryo‐EM structures of nucleosome core particles containing human H2A.B (H2A.B‐NCP) at atomic resolution, identifying large‐scale structural rearrangements in the histone octamer in H2A.B‐NCP. H2A.B‐NCP compacts approximately 103 bp of DNA wrapping around the core histones in approximately 1.2 left‐handed superhelical turns, in sharp contrast to canonical nucleosome encompassing approximately 1.7 turns of DNA. Micrococcal nuclease digestion assay reveals that nineteen H2A.B‐specific residues, including a ROF (“regulating‐octamer‐folding”) sequence of six consecutive residues, are responsible for loosening of H2A.B‐NCPs. Unlike H2A.B‐NCP, the H2A.Z.2.2‐containing nucleosome (Z.2.2‐NCP) adopts a less‐extended structure and compacts around 125 bp of DNA. Further investigation uncovers a crucial role for the H2A.Z.2.2‐specific ROF in both H2A.Z.2.2‐NCP opening and SWR1‐dependent histone replacement. Taken together, these first high‐resolution structure of unstable nucleosomes induced by histone H2A variants elucidate specific functions of H2A.B and H2A.Z.2.2 in enhancing chromatin dynamics.  相似文献   

20.
Amazonia forest plays a major role in providing ecosystem services for human and sanctuaries for wildlife. However, ongoing deforestation and habitat fragmentation in the Brazilian Amazon has threatened both. The ocelot is an ecologically important mesopredator and a potential conservation ambassador species, yet there are no previous studies on its habitat preference and spatial patterns in this biome. From 2010 to 2017, twelve sites were surveyed, totaling 899 camera trap stations, the largest known dataset for this species. Using occupancy modeling incorporating spatial autocorrelation, we assessed habitat use for ocelot populations across the Brazilian Amazon. Our results revealed a positive sigmoidal correlation between remote‐sensing derived metrics of forest cover, disjunct core area density, elevation, distance to roads, distance to settlements and habitat use, and that habitat use by ocelots was negatively associated with slope and distance to river/lake. These findings shed light on the regional scale habitat use of ocelots and indicate important species–habitat relationships, thus providing valuable information for conservation management and land‐use planning.  相似文献   

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