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1.
植物吸收利用有机氮营养研究进展 总被引:4,自引:0,他引:4
植物矿质营养学问世以后,人们一直认为无机氮是植物吸收氮素的主要形态.随着研究手段的改进和研究内容的不断深入,现已证实许多没有菌根的维管植物都可以直接吸收可溶性有机氮,特别是小分子的氨基酸.由此引起了人们对植物有机营养、植物营养方式多样化问题的重视.研究表明:氨基酸可以通过多种方式释放到土壤溶液中,土壤中的氨基酸主要来源于微生物、动植物及其代谢产物等.土壤氨基酸含量受土壤温湿度、所施的有机肥料、生长的植物种类及其生长发育时期的影响.植物对氨基酸的吸收是一个主动吸收过程,受载体调节,并与能量状况有关,同时受介质中pH和温度的影响.但是有关植物吸收氨基酸的机理及其生态过程还需进行深入的研究. 相似文献
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Guilherme B. Ferreira Jorge A. Ahumada Marcelo J. R. Oliveira Fernando F. de Pinho Izabela M. Barata Chris Carbone Ben Collen 《Biotropica》2017,49(5):734-744
Debate about the conservation value of secondary habitats has tended to focus on tropical forests, increasingly recognizing the role of secondary forests for biodiversity conservation. However, there remains a lack of information about the conservation value of secondary savannas. Here, we conducted a camera trap survey to assess the effect of secondary vegetation on large mammals in a Brazilian Cerrado protected area, using a single‐season occupancy framework to investigate the response of individual species (species‐level models) and of all species combined (community‐level models). In addition, we investigated the cost effectiveness of different sampling designs to monitor globally threatened species in the study area. At the community level, savanna that regenerated from eucalyptus plantation had similar occupancy estimate as old growth areas. At the species level, none of the ten species individually assessed seemed to respond to succession stage, with greater support for the effect of other covariates on occupancy, such as distance from water and vegetation physiognomy. These results demonstrate that secondary vegetation does not appear to negatively impact large mammals in the study area and suggest that, given a favorable context, Cerrado mammals can recolonize and use secondary savannas that regenerated from clearcut. However, our study area should be considered a best‐case scenario, as it retained key ecological attributes of high‐value secondary habitats. Our simulations showed that a sampling design with 60 camera trap sites surveyed during nine occasions is appropriate to monitor most globally threatened species in the study area, and could be a useful starting point for new monitoring initiatives in other Cerrado areas. 相似文献
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Willem A. Nieman;Alexander E. Botha; 《African Journal of Ecology》2024,62(1):e13223
Large transboundary protected areas such as the Kavango-Zambezi Transfrontier Conservation Area (KAZA-TFCA), improve mammal conservation by addressing biodiversity threats on regional and international levels, but an adequate understanding of mammal space use and richness within protected areas is critical for effective management planning. This information has however been missing from the Angolan component of the KAZA-TFCA, such as areas of Luengue-Luiana National Park (LLNP), especially compared with neighbouring countries. We used camera trap data from 2021 to 2023 to investigate species richness of medium- and large-sized mammals in two hotspot areas of LLNP, as well as assess the space use patterns of 9 carnivore and 16 herbivore species. A total of 48 species were recorded over 10,781 camera trapping nights, with African elephant (Loxodonta africana) and small antelope (e.g. common duiker Sylvicapra grimmia and steenbok Raphicerus campestris) being the most common. Species composition differed significantly between sites, with 21 species more relatively abundant at Ndunjuru, including cheetah (Acinonyx jubatus) and African wild dog (Lycaon pictus), and eight species more relatively abundant at Bico, including lion (Panthera leo) and hippopotamus (Hippopotamus amphibius). The detection probability of 22 species were affected by one or more ecological (e.g. proximity to rivers) or anthropogenic (e.g. human settlement) covariate. These results are intended to act as a baseline to monitor conservation effort and aid habitat management in LLNP, as well as similar protected areas within the KAZA-TFCA and elsewhere. 相似文献
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Yoshihiro Nakashima 《Population Ecology》2020,62(1):151-157
Reliable and accurate information on animal abundance is fundamental for the conservation and management of wildlife. Recently, a number of innovative devices (such as camera traps) have been widely used in field surveys and have largely improved survey efficiency. However, these devices often constitute noninstantaneous point surveys, resulting in the multiple counts of the same animal individuals within a single sampling occasion (i.e., false-positive errors). Many commonly-used statistical models do not explicitly account for the false-positive error, with its effects on estimates being poorly understood. Here, I tested the performance of the commonly-used Poisson-binomial N-mixture and the Royle-Nichols model in the presence of both false-positive and negative errors (i.e., individuals in a population might not be detected). I also implemented the Poisson-Poisson mixture model in the Bayesian framework to evaluate its reliability. The results of the simulation using random walks based on Ornstein-Uhlenbeck processes showed that the Poisson-binomial model was not robust to false-positive errors. In comparison, the Royle-Nichols and Poisson-Poisson models provided reasonable estimates of the number of animals whose home range included the survey point. However, the number of animals whose home range included the survey point is inherently influenced by the size of animal home ranges, and thus cannot be used as a surrogate of animal density. Although the N-mixture and Royle-Nichols models are widely used, their utility might be restricted by this limitation. In conclusion, studies should clearly define the objective of surveys and carefully consider whether the models used are valid. 相似文献
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龚翠凤;韦伟;罗概;韩一敏;吴鹏程;何梦楠;闵清悦;付强;陈鹏 《生物多样性》2025,33(3):133-145
空间生态位分化是生物多样性维持的重要机制之一。为了解大熊猫国家公园崇州片区有蹄类的空间生态位分化情况, 本文于2021年10月至2022年3月在该区域布设了56台红外相机, 采用单季节单物种占域模型计算域内主要6种有蹄类动物的占域率, 包括毛冠鹿(Elaphodus cephalophus)、野猪(Sus scrofa)、水鹿(Rusa unicolor)、扭角羚(Budorcas taxicolor)、中华斑羚(Naemorhedus griseus)和小麂(Muntiacus reevesi), 分析其空间分布情况, 并进一步采用单季节双物种占域模型计算这些物种间的物种相互作用因子(species interaction factor, SIF)值, 探究它们的空间共存关系。结果显示: (1)毛冠鹿具有最高的空间占域率(0.61), 野猪次之(0.55), 水鹿、扭角羚和中华斑羚分别为0.44、0.41和0.11, 小麂占域率最低(0.05); (2)有蹄类动物的占域率受到环境变量的影响, 其中海拔是影响上述6种有蹄类动物分布的主要因素; (3)在空间共存关系上, 水鹿与除野猪外的其他有蹄类不存在明显回避, 毛冠鹿与野猪和扭角羚之间也不存在明显回避, 而其他物种相互之间空间分布更多呈回避关系。研究结果表明环境因素影响着崇州区域有蹄类物种的空间生态位, 同时, 物种间的空间分布格局显著影响了同域分布动物的共存机制及种间竞争关系。本研究为保护和管理大熊猫国家公园崇州片区有蹄类动物提供了重要的科学依据, 突出了在物种多样性保护中考虑空间生态位分化的重要性。 相似文献
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占域模型解决了探测率常常被忽略的问题, 所需数据要求简单, 具有数据来源广泛、经济高效等优点, 越来越多地应用在野生动物监测和研究中。本文综述了占域模型的概念、基本原理及其近年来在国内外的应用进展, 并以红外相机数据为基础, 总结了占域模型所要求的数据采集、处理和分析等流程和基本原则, 同时以广东车八岭国家级自然保护区的花面狸(Paguma larvata)作为研究案例, 展示了占域模型的数据分析过程。最后根据近年来的发展和应用, 总结了占域模型的应用范围和发展趋势以及研究中存在的主要问题。 相似文献
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Chad T. Beranek;Darren Southwell;Tim S. Jessop;Benjamin Hope;Veronica Fernandes Gama;Nicole Gallahar;Elliot Webb;Brad Law;Allen McIlwee;Jared Wood;Adam Roff;Graeme Gillespie; 《Ecology and evolution》2024,14(7):e11659
Quantifying the cost-effectiveness of alternative sampling methods is crucial for efficient biodiversity monitoring and detection of population trends. In this study, we compared the cost-effectiveness of three novel sampling methods for detecting changes in koala (Phascolarctos cinereus) occupancy: thermal drones, passive acoustic recorders and camera trapping. Specifically, we fitted single-season occupancy-detection models to data recorded from 46 sites in eight bioregions of New South Wales, Australia, between 2018 and 2022. We explored the effect of weather variables on daily detection probability for each method and, using these estimates, calculated the statistical power to detect 30%, 50% and 80% declines in koala occupancy. We calculated power for different combinations of sites (1–200) and repeat surveys (2–40) and developed a cost model that found the cheapest survey design that achieved 80% power to detect change. On average, detectability of koalas was highest with one 24-h period of acoustic surveys (0.32, 95% CI's: 0.26, 0.39) compared to a 25-ha flight of drone surveys (0.28, 95% 0.15, 0.48) or a 24-h period of camera trapping consisting of six cameras (0.019, 95% CI's: 0.014, 0.025). We found a negative quadratic relationship between detection probability and air temperature for all three methods. Our power and cost analysis suggested that 148 sites surveyed with acoustic recorders deployed for 14 days would be the cheapest method to sufficiently detect a 30% decline in occupancy with 80% power. We recommend passive acoustic recorders as the most efficient sampling method for monitoring koala occupancy compared to cameras or drones. Further comparative studies are needed to compare the relative effectiveness of these methods and others when the monitoring objective is to detect change in koala abundance over time. 相似文献
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Hannah L. Clipp;Sarah M. Pesi;Madison L. Miller;Laura C. Gigliotti;Brett P. Skelly;Christopher T. Rota; 《Ecology and evolution》2024,14(3):e11149
Predator species can indirectly affect prey species through the cost of anti-predator behavior responses, which may involve shifts in occupancy, space use, or movement. Quantifying the various strategies implemented by prey species to avoid adverse interactions with predators can lead to a better understanding of potential population-level repercussions. Therefore, the purpose of this study was to examine predator–prey interactions by quantifying the effect of predator species presence on detection rates of prey species, using coyotes (Canis latrans) and white-tailed deer (Odocoileus virginianus) in Central Appalachian forests of the eastern United States as a model predator–prey system. To test two competing hypotheses related to interspecific interactions, we modeled species detections from 319 camera traps with a two-species occupancy model that incorporated a continuous-time detection process. We found that white-tailed deer occupancy was independent of coyote occupancy, but white-tailed deer were more frequently detectable and had greater detection intensity at sites where coyotes were present, regardless of vegetation-related covariates. In addition, white-tailed deer detection rates at sites with coyotes were highest when presumed forage availability was relatively low. These findings suggest that white-tailed deer may be exhibiting an active avoidance behavioral response to predators by increasing movement rates when coyotes are present in an area, perhaps due to reactive evasive maneuvers and/or proactive attempts to reduce adverse encounters with them. Concurrently, coyotes could be occupying sites with higher white-tailed deer densities. Because white-tailed deer did not exhibit significant shifts in daily activity patterns based on coyote occupancy, we further suggest that white-tailed deer in our study system generally do not use temporal partitioning as their primary strategy for avoiding encounters with coyotes. Overall, our study implements a recently developed analytical approach for modeling multi-species occupancy from camera traps and provides novel ecological insight into the complex relationships between predator and prey species. 相似文献
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Anthony R. Rendall John G. White Raylene Cooke Desley A. Whisson Thomas Schneider Lisa Beilharz Eleanor Poelsma Julia Ryeland Michael A. Weston 《Ecological Management & Restoration》2021,22(1):72-79
Autonomously triggered cameras are a common wildlife survey technique. The use of attractants and surrounding microhabitats is likely to influence detection probabilities and survey outcomes; however, few studies consider these factors. We compared three attractants (peanut butter‐based, tuna‐based and a control) in a Latin square design through a coastal shrubland with high microhabitat variability at Cape Otway, Victoria, Australia (38º50?S, 143º30?E). Deployments involved 36 cameras for four days in each of five years. The percentage cover of each vegetation structural type (low [no or sparse cover], moderate [grass] or high [shrubs]) within 20 m of each camera was calculated and reduced to a single variable using PCA. Dynamic occupancy modelling, with lure type and vegetation structure as covariates of detection probability, found that peanut butter attracted the greatest diversity of species (24 of 35 species, 69%) and yielded the greatest number of detections (50% of 319) when compared with tuna oil (66% and 24%, respectively) and the control (43% and 26%, respectively). Peanut butter attracted more Macropodidae (wallabies) and Muridae (rats and mice); however, vegetation structural variables were the greatest influence on Corvidae/Artamidae (raven/currawong) detections with higher detectability in more open areas. Vegetation structure also influenced Muridae detections. This study reinforces the critical choice of appropriate attractants and camera placement when investigating vertebrate groups and highlights the role of microhabitat in the detection of small mammals and birds. We suggest future large‐scale camera surveys consider different bait types and microhabitats in their designs, to control for any biases and enable future advice on ‘optimal’ methods. 相似文献
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Michael V. Cove Theodore R. Simons Beth Gardner Andrew S. Maurer Allan F. O'Connell 《Restoration Ecology》2017,25(2):253-260
The Key Largo woodrat (Neotoma floridana smalli) and Key Largo cotton mouse (Peromyscus gossypinus allapaticola) are federally endangered subspecies endemic to the tropical hardwood hammocks of Key Largo, Florida. Woodrats are considered generalists in habitat and diet, yet a steady decline in natural stick nests and capture rates over the past several decades suggests that they are limited by the availability of nesting habitat due to habitat loss and fragmentation. The more specialized Key Largo cotton mouse appears to rely on old growth hammock, a habitat type that is rare following past land clearing. In 2004, the U.S. Fish and Wildlife Service started building supplemental nest structures to restore habitat quality and connectivity for these endangered rodents, but nest use requires evaluation. We used camera traps and occupancy models to evaluate the factors influencing woodrat and cotton mouse use of the supplemental nests. We detected woodrats at 65 and cotton mice at 175 of 284 sampled nest structures, with co‐occurrence at 38 nests. Woodrat nest use followed a gradient from low nest use in the north to high nest use in the south, which might relate to the proximity of free‐ranging domestic cat (Felis catus) colonies in residential developments. Cotton mouse nest use, however, was related positively to mature hammock and related negatively to disturbed areas (e.g. scarified lands). The two species occurred independently of each other. Stick‐stacking behavior was observed at supplemental nests and, although it was correlated with detection of woodrats, it was not a strong predictor of their occurrence. We suggest that nest supplementation can be an important tool for species recovery as habitat quality continues to improve with succession. 相似文献
11.
Competition drives community composition and structure in many ecosystems. Spatial and temporal niche partitioning, in which competing species divide the environment in space or time, are mechanisms that may allow for coexistence among ecologically similar species. Such division of resources may be especially important for carnivores in African savannas, which support diverse carnivore assemblages. We used camera traps to explore patterns of spatial and temporal niche partitioning among four mesocarnivore species in Mozambique's Gorongosa National Park: large-spotted genet (Genetta maculata), African civet (Civettictis civetta), honey badger (Mellivora capensis) and marsh mongoose (Atilax paludinosus). We applied a multispecies occupancy model to evaluate spatial partitioning among mesocarnivores and to quantify the environmental factors that affect species-specific habitat use, including relative lion (Panthera leo) activity. We also analyzed the temporal activity overlap of the four focal species. We identified species-specific habitat covariates that influenced detection probabilities but found no evidence of spatial or temporal partitioning among mesocarnivores in the study system. Indeed, we found some evidence for spatial co-occurrence between two of our focal species: African civet and marsh mongoose. There may be limited competition among mesocarnivores in this system, perhaps due to niche and diet differentiation among these species and an abundance of resources. While we found limited evidence that lion activity impacts mesocarnivores, ongoing monitoring of intraguild interactions is vital as apex predator populations recover in the system. This study adds to a growing understanding of African mesocarnivore ecology and highlights the importance of understanding these dynamics for effective multispecies conservation and restoration. 相似文献
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Jamie McCallum 《Mammal Review》2013,43(3):196-206
- Camera traps are automated cameras, triggered by movements, used to collect photographic evidence of the presence of animals in field research. I asked whether the use of camera traps in mammalian field research is distributed evenly and increasing equally in a range of habitats, taxa and study types. I aimed to understand where camera traps are used and for what purposes.
- I identified the population of papers published since 1994 in which camera trap methodology was used. I then explored the population for defined habitats, taxa and study types. I tested the derived data for growth and distribution. Over 96% of the population of camera trap papers identified were focused on mammalian species.
- Between 1994 and 2011, the use of camera traps for mammalian research increased: 73% of 414 studies were published after 2005. Over time, equipment has become more sophisticated, reliable, flexible, cost‐effective and easy to deploy, and there have been other methodological advances.
- Growth in the number of mammal‐related camera trap studies was matched by an expansion in the taxa studied and in study types. The most studied taxon is the order Carnivora; forests are the most studied habitat. No single study type dominates, although there are more population density studies than any other. Camera trap studies are focused on a limited number of habitats and taxa due to their particular strengths and the characteristics of the species that they are used to investigate.
- Developments such as infrared illumination and triggering, greater battery life, improved lenses, digital storage capacity, miniaturization, video and real‐time links will enable camera traps to be used for an increasing range of habitats, taxa and study types and will reinforce their growing value in the areas in which they currently predominate.
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Curt H. Barnes;Ungku Zafirah Abdulaziz;Arwut Kaenphet;Chatchai Kanlayanapaphon; 《Ecology and evolution》2024,14(9):e70317
More than 240 species of snake have been described from Thailand, yet basic natural history and ecology for this group of animals remains scarce in human disturbed environments despite conservation and human medical significance of them in these habitats. We studied snake diversity at Walailak University from March to December 2023, the largest university campus in Thailand (1525 hectares) through standardized walking surveys, opportunistic notifications and observation, road surveys, and traps and evaluated diversity using the Shannon diversity index (H), Pielou's evenness of species (J), detection probabilities (p), and occupancy probabilities (ψ). We observed 195 snakes (21 species, 7 families) at Walailak University and overall snake diversity (H = 2.60) and evenness (J = 0.85) were quite high, although specific site diversity (range H = 0–1.94) and evenness (range J = 0.67–0.91) within the university were variable. The probability of detecting snakes (range p = .10–.40) increased with increasing humidity and decreased with increasing amount of rain, temperature, and wind; site occupancy probability decreased with increased canopy height and increased with increased distance to buildings, increased canopy height loss, increased distance to roads, and increased distance to water. Our findings of relatively high snake diversity, presence of snake species potentially dangerous to humans (six species), and protected snake species (Thailand WARPA and international CITES, five species) suggest significant potential for conservation and further research at Walailak University and other campuses in Thailand. 相似文献
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大型食肉动物对维持生态系统的结构和功能具有重要作用, 但大部分大型食肉动物处在持续的种群数量和分布面积下降之中, 面临着急迫的研究与保护需求。华北豹(Panthera pardus japonensis)是我国特有的豹亚种, 也是部分区域森林生态系统中仅存的大型食肉动物, 面临着生境破碎化等威胁。本研究使用红外相机调查了宁夏六盘山国家级自然保护区华北豹的分布, 通过构建占域模型分析了华北豹的栖息地利用, 预测了华北豹的适宜栖息地, 并评估了其生境破碎化格局。研究发现, 华北豹在六盘山的平均占域率约为0.135。华北豹偏好植被发育成熟、地势崎岖、温度较低、远离农田和公路的栖息地, 对于农田边缘和居民点等人类活动区域未显示出显著回避。研究识别的六盘山华北豹适宜栖息地主要沿六盘山东西两侧山脉分布, 55%的适宜栖息地斑块位于六盘山国家级自然保护区内。栖息地斑块面积平均为16 km2, 最大达214 km2, 约77%的栖息地斑块面积在10 km2以下。研究表明六盘山国家级自然保护区有效地保护了华北豹现有的适宜栖息地, 但仍存在栖息地破碎化和人类活动干扰等关键限制因素。建议通过栖息地改造、人类活动管理等方式增强六盘山华北豹适宜栖息地斑块连通性; 并通过推动华北豹跨省保护工作等举措促进华北豹种群扩散恢复。 相似文献
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Worrapan Phumanee Robert Steinmetz Rungnapa Phoonjampa Suthon Weingdow Surachai Phokamanee Naris Bhumpakphan Tommaso Savini 《Conservation Science and Practice》2021,3(12):e560
Landscape-scale strategies for conserving wild tigers emphasize the role of core breeding populations (source sites) to replenish surrounding areas which have lost tigers. In Southeast Asia, a few potential source sites remain, particularly Huai Kha Khaeng Wildlife Sanctuary, Thailand (HKK). We investigated tiger density in two reserves (Mae Wong, Khlong Lan: MWKL) adjacent to HKK where tigers and their prey were scarce due to historic poaching but current management offered effective protection. Camera trapping revealed 10 adult tigers (four males, six females), at least two of which had immigrated from HKK. Spatially explicit tiger density was 0.359 tigers/100 km2, 5.6 times lower than HKK. The population was breeding, with six cubs observed. Tiger movements (measured by σ, the spatial scale parameter) were twice as extensive in MWKL as in HKK, indicative of prey scarcity in MWKL. The disparity in density between MWKL and HKK reveals that tiger recovery is a slow process when prey are scarce, even when recovery areas are apparently well-managed and connected to a source site. We review source-recovery dynamics of tigers in other sites in Asia and find that low prey impedes landscape-scale recoveries elsewhere as well. 相似文献
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Maud Petitot Nicolas Manceau Philippe Geniez Aurélien Besnard 《Ecology and evolution》2014,4(18):3538-3549
- Setting up effective conservation strategies requires the precise determination of the targeted species’ distribution area and, if possible, its local abundance. However, detection issues make these objectives complex for most vertebrates. The detection probability is usually <1 and is highly dependent on species phenology and other environmental variables. The aim of this study was to define an optimized survey protocol for the Mediterranean amphibian community, that is, to determine the most favorable periods and the most effective sampling techniques for detecting all species present on a site in a minimum number of field sessions and a minimum amount of prospecting effort. We visited 49 ponds located in the Languedoc region of southern France on four occasions between February and June 2011. Amphibians were detected using three methods: nighttime call count, nighttime visual encounter, and daytime netting. The detection nondetection data obtained was then modeled using site‐occupancy models. The detection probability of amphibians sharply differed between species, the survey method used and the date of the survey. These three covariates also interacted. Thus, a minimum of three visits spread over the breeding season, using a combination of all three survey methods, is needed to reach a 95% detection level for all species in the Mediterranean region. Synthesis and applications: detection nondetection surveys combined to site occupancy modeling approach are powerful methods that can be used to estimate the detection probability and to determine the prospecting effort necessary to assert that a species is absent from a site.
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Angela K. Fuller Daniel W. Linden J. Andrew Royle 《The Journal of wildlife management》2016,80(5):794-802