利用自动相机对东北虎分布区兽类的监测

2012～2013年期间,在黑龙江省东北虎主要分布的5个林业局9个林场布设68台远红外自动相机对东北虎等兽类资源进行监测的结果表明：拍摄到兽类5目10科19种,照片1166张。在3个林业局拍摄到东北虎影像,但由于拍摄到东北虎的次数少,不足以统计东北虎的种群数量。野外监测拍摄到东北虎、东北豹、原麝、梅花鹿、猞猁、黑熊等珍稀濒危物种,为确认其分布区提供了依据。自动相机监测结果也可以用于评估东北虎不同分布区有蹄类猎物的种群密度。     

Aspen demographics in relation to spatial context and ungulate browsing: Implications for conservation and forest management

Aspen has a high conservation value and has been targeted as a priority species in sustainable forest management. However, sustained and intense browsing pressure by ungulates has raised concerns about the recruitment of aspen to mature growth stages. Here we investigate the influence of ungulate browsing on the demographic structure of European aspen populations in two managed boreal forest areas in Sweden with contrasting amounts of aspen and high densities of ungulates. The contrast in size distribution of ramets in the two areas was striking. The aspen-poor environment contained a much lower density of small-sized ramets than the aspen-rich environment. Ramet abundance was strongly associated with the abundance of ramets in the smaller size classes in both areas, reflecting demographic inertia in these populations. Ungulate use was most strongly associated with abundance of medium-sized aspen saplings growing in forest interiors. Otherwise, use of ungulates was only weakly correlated with aspen population parameters. The strong demographic momentum exhibited by these populations suggests that aspen conservation and management should pay more attention to additional factors than browsing to promote ramet establishment. Large variation in abundance of ramets in the smallest size-class shows that some aspen stands have a disproportionate effect on aspen recruitment, particularly in areas where aspen is less abundant. Identifying aspen stands with a large capacity for self regeneration may be the key to meet aspen conservation goals.     

新疆塔什库尔干岩羊和北山羊种群密度调查

有蹄类动物为新疆塔什库尔干地区分布的雪豹、狼和猞猁等捕食动物提供了重要的食物资源。为了掌握该地区主要野生有蹄类动物的种群密度,于2009年2～3月通过车行样线和步行样线2种调查方式,采用距离取样方法,对岩羊和北山羊种群数量进行了调查分析。车行样线调查获得的岩羊密度为1.791～6.751只/km~2,北山羊密度为0～0.140只/km~2。步行样线调查获得的密度较低,岩羊和北山羊分别为0.008～0.698只/km~2和0.023～0.252只/km~2。调查结果显示该地区岩羊和北山羊种群密度较上世纪80年代中期有所下降。     

Introducing spatial grazing impacts into the prediction of moorland vegetation dynamics

Grazing by large herbivores is a major determinant of vegetation dynamics in many semi-natural ecosystems, including the replacement of heather moorland by rough grassland in the British uplands. Herbivore foraging is influenced by vegetation patterns and, in turn, their grazing drives vegetation dynamics. Although vegetation impacts are local, spatially heterogeneous local impacts can have different consequences as would the same impacts distributed uniformly. We constructed a simulation model of the spatial effects of grazing by sheep on the vegetation dynamics of heather moorland, a vegetation community of international conservation importance in the UK. The model comprised three sub-models to predict (1) annual average heather utilisation, (2) spatial variation in heather utilisation (higher near the edge of grass patches) and (3) competition between heather and grass. Here we compare the predicted heather utilisation and vegetation dynamics of the spatial model, relative to those of a non-spatial model. The spatial model resulted in a reduced loss of heather cover for a given sheep stocking rate. The model demonstrates how spatial interactions between large herbivores and their forage drive vegetation dynamics, leading to changes in community structure and composition. Indeed, omitting spatial effects in grazing models may lead to inaccurate predictions. We have shown that ecosystem modelling, based around an iterative dialogue between developers and experienced researchers, has the potential to make a substantial contribution towards the conservation and management of vulnerable landscapes. Combining modelling with experimental studies will facilitate progress towards understanding long-term vegetation/herbivore dynamics.     

Modeling successional patterns of high-elevation forests under changing herbivore pressure – responses at the landscape level

We describe an ecological risk assessment for determining the potential long-term impacts of browsing by red deer, roe deer and chamois on the stand dynamics of mountain forests in xeric parts of Central Europe. The assessment is performed by applying a forest succession model of the FORET/JABOWA type which was supplemented with an empirically based browsing subroutine to simulate the effects of browsing by red and roe deer, and chamois. The following scenarios are assumed: (1) no browsing; (2) actual browsing intensity as determined in field trials; (3) browsing intensity twice as high as in scenario (2); and (4) browsing intensity three times as high as in scenario (2). The simulations for two different forest sites in the subalpine region of Eastern Switzerland revealed that heavy browsing can alter development and composition of the observed forests. The extent of this alteration was influenced not only by high browsing intensity, but also by the selection of tree species which were browsed on a particular site at the same time. Taking into account all the uncertainties of the model approach, we conclude from our preliminary studies that, in the regions considered, even strong herbivore pressure (2–3 times today's values) is not a major threat for the survival of the forest as a biological resource, i.e. the long-term total woody biomass is not altered significantly and the changes in the successional pathways are not dramatic. High browsing intensities, however, alter the forest structure considerably. We found that heavily browsed forests tend to be more open, mortality is higher and trees reach an intermediate and adult size quicker. This shortened development cycle of the stands may have implications for forest functions. The risk assessment yields critical values for mean browsing intensity, ‘MBI', (Pinus cembra/Pinus mugo: 30%; Picea abies: 50%; and Larix decidua: 40%), below which successional patterns and forest structures with browsing are not significantly different from forest succession without browsing.     

Yellowstone’s ungulates after wolves - expectations, realizations, and predictions

We evaluated the initial implications of wolf (Canis lupus) recovery on ungulates in Yellowstone National Park and compared expectations prior to wolf restoration with observed impacts since restoration. The numerical and functional responses of colonizing wolves in Yellowstone’s prey-rich environment were higher than expected and close to the maximum rates predicted prior to wolf restoration. Counts of northern Yellowstone elk (Cervus elaphus) decreased more (50%) than predicted (5-30%), and will likely continue to decrease given the strong preference of wolves for elk and continued high kill rates despite this substantial reduction in elk abundance. Contrary to expectations, human harvests were not reduced appreciably concurrent with wolf restoration, but instead remained similar to pre-wolf restoration years. However, antler-less permits were gradually reduced by 51% during 2000-2004 and additional reductions may be necessary while wolf densities remain high. There have been no substantial effects of wolf recovery on other ungulate species (bighorn sheep (Ovis canadensis), bison (Bison bison), moose (Alces alces), mule deer (Odocoileus hemionus), pronghorn (Antilocapra americana)). However, wolf recovery may eventually contribute to increased bison and pronghorn abundance by decreasing elk and coyote abundance, respectively. Wolf recovery may also contribute to more-pronounced spatial structuring of sex/age classes of northern Yellowstone elk through changes in their distribution, migration, and age structure. The initial consequences of wolf recovery support the premise that wolves may naturally achieve densities above their threshold for ecological effectiveness and contribute to significant changes in ecosystems, including the amelioration of ungulate-caused landscape simplification.     

Large predators and trophic cascades in terrestrial ecosystems of the western United States

Large predators potentially can help shape the structure and functioning of terrestrial ecosystems, yet strong evidence of top-down herbivore limitation has not been widely reported in the scientific literature. Herein we synthesize outcomes of recent tri-trophic cascades studies involving the presence and absence of large predators for five national parks in the western United States, including Olympic, Yosemite, Yellowstone, Zion, and Wind Cave. Historical observations by park biologists regarding woody browse species and recently compiled age structure data for deciduous trees indicate major impacts to woody plant communities by ungulates following the extirpation or displacement of large predators. Declines in long-term tree recruitment indexed additional effects to plant communities and ecological processes, as well as shifts towards alternative ecosystem states. The magnitude and consistency of vegetation impacts found within these five parks, in conjunction with other recent North American studies, indicate that broad changes to ecosystem processes and the lower trophic level may have occurred in other parts of the western United States where large predators have been extirpated or displaced. Thus, where ungulates have significantly altered native plant communities in the absence of large predators, restoration of native flora is urgently needed to recover former ecosystem services. Following the reintroduction of previously extirpated gray wolves Canis lupus into Yellowstone National Park, a spatially patchy recovery of woody browse species (e.g., aspen Populus tremuloides, willow Salix spp., cottonwood Populus spp.) has begun, indicating that large predator recovery may represent an important restoration strategy for ecosystems degraded by wild ungulates.     

基于红外相机的白水河国家级自然保护区偶蹄类活动节律调查

2017年6月—2018年9月,在四川白水河国家级自然保护区利用红外相机对保护区内偶蹄类物种活动节律进行研究.结果显示:1、保护区内共发现六种偶蹄类动物,分别为羚牛、斑羚、鬣羚、林麝、毛冠鹿、野猪.相对多度结果显示,最高的为斑羚(RAI=51.2)和毛冠鹿(RAI=32.6),明显高于其他物种.其余依次为林麝(RAI=...     

有蹄类营养生态学研究进展

有蹄类动物营养生态学是一门正在兴起的新学科,是现代生态学领域研究动物食物数量和质量、营养适应以及营养对种群特征作用规律的分支学科.动物种群和其环境中食物资源的相互关系及作用机理构成了这一学科的基本研究内容.本文从食性分析、营养状况评价、食物营养质量评价、消化与能量代谢、取食行为、营养容纳量和营养生态位等主要方面对这一学科进行了探讨.