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91.
Authors of socioecological models propose that food distribution affects female social relationships in that clumped food
resources, such as fruit, result in strong dominance hierarchies and favor coalition formation with female relatives. A number
of Old World monkey species have been used to test predictions of the socioecological models. However, arboreal forest-living
Old World monkeys have been understudied in this regard, and it is legitimate to ask whether predominantly arboreal primates
living in tropical forests exhibit similar or different patterns of behavior. Therefore, the goal of our study was to investigate
female dominance relationships in relation to food in gray-cheeked mangabeys (Lophocebus albigena). Since gray-cheeked mangabeys are largely frugivorous, we predicted that females would have linear dominance hierarchies
and form coalitions. In addition, recent studies suggest that long food site residence time is another important factor in
eliciting competitive interactions. Therefore, we also predicted that when foods had long site residence times, higher-ranking
females would be able to spend longer at the resource than lower-ranking females. Analyses showed that coalitions were rare
relative to some other Old World primate species, but females had linear dominance hierarchies. We found that, contrary to
expectation, fruit was not associated with more agonism and did not involve long site residence times. However, bark, a food
with a long site residence time and potentially high resource value, was associated with more agonism, and higher-ranking
females were able to spend more time feeding on it than lower-ranking females. These results suggest that higher-ranking females
may benefit from higher food and energy intake rates when food site residence times are long. These findings also add to accumulating
evidence that food site residence time is a behavioral contributor to female dominance hierarchies in group-living species. 相似文献
92.
2012年5月至2013年4月,在苏州工业园区选择了4种生境,设置了17条样线、24个样点,逐月对鸟类群落进行了研究。共记录到鸟类130种,隶属12目41科,雀形目鸟类占主要地位,其中留鸟、夏候鸟、冬候鸟和旅鸟分别占鸟类总种数的26.15%、25.38%、27.69%和20.77%。区系以广布种和古北界种类为主,兼有东洋界种类,具有南北过渡的明显特征。从季节动态变化上看,园区鸟种数由多到少表现为春季冬季秋季夏季;密度由高到低表现为冬季秋季春季夏季。湿地生境鸟类种数最多,分布均匀;道路生境鸟类种数最少,分布不均,但优势种突出,以常见的伴人雀形目鸟类为主。聚类结果显示,环境条件是影响鸟类组成的重要因素。 相似文献
93.
Ryan Perkl David Mitchell Mark Feller Garrett Smith Natalie R. Wilson 《Journal of Land Use Science》2018,13(1-2):102-117
Urban and exurban expansion results in habitat and biodiversity loss globally. We hypothesize that a coupled-model approach could connect urban planning for future cities with landscape ecology to consider wildland habitat connectivity. Our work combines urban growth simulations with models of wildlife corridors to examine how species will be impacted by development to test this hypothesis. We leverage a land use change model (SLEUTH) with structural and functional landscape-connectivity modeling techniques to ascertain the spatial extent and locations of connectivity related threats to a national park in southern Arizona, USA, and describe how protected areas might be impacted by urban expansion. Results of projected growth significantly altered structural connectivity (80%) when compared to current (baseline) corridor conditions. Moreover, projected growth impacted functional connectivity differently amongst species, indicating resilience of some species and near-complete displacement of others. We propose that implementing a geospatial-design-based model will allow for a better understanding of the impacts management decisions have on wildlife populations. The application provides the potential to understand both human and environmental impacts of land-system dynamics, critical for long-term sustainability. 相似文献
94.
An agent-based model of red colobus resources and disease dynamics implicates key resource sites as hot spots of disease transmission 总被引:1,自引:0,他引:1
The effect of anthropogenic landscape change on disease in wildlife populations represents a growing conservation and public health concern. Red colobus monkeys (Procolobus rufomitratus), an endangered primate species, are particularly susceptible to habitat alteration and have been the focus of a great deal of disease and ecological research as a result. To infer how landscape changes can affect host and parasite dynamics, a spatially explicit agent-based model is created to simulate movement and foraging of this primate, based on a resource landscape estimated from extensive plot-derived tree population data from Kibale National Park, Uganda. Changes to this resource landscape are used to simulate effects of anthropogenic forest change. With each change in the landscape, disease outcomes within the simulated red colobus population are monitored using a hypothetical microparasite with a directly transmitted life cycle. The model predicts an optimal distribution of resources which facilitates the spread of an infectious agent through the simulated population. The density of resource rich sites and the overall heterogeneity of the landscape are important factors contributing to this spread. The characteristics of this optimal distribution are similar to those of logged sections of forest adjacent to our study area. 相似文献
95.
国家公园效果评价体系研究 总被引:1,自引:0,他引:1
建立国家公园是保护生物多样性和促进地方发展的重要途径之一,开展国家公园效果评价是了解国家公园功能发挥的有效途径。通过查阅大量文献及德尔菲法(Delphi),确定了与国家公园效果相关的28个评价指标,同时以功能为主导,将评价指标归纳为5个功能指标群:保护功能指标群(7个评价指标)、科研功能指标群(6个评价指标)、游憩功能指标群(7个评价指标)、教育功能指标群(4个评价指标)和经济发展功能指标群(4个评价指标),通过对评价指标的赋分(5分制原则)和计算权重,从而达到国家公园效果评价的量化,实现对国家公园建设效果的评价。 相似文献
96.
97.
Pairing Modern and Paleolimnological Approaches to Evaluate the Nutrient Status of Lakes in Upper Midwest National Parks
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David D. VanderMeulen Brenda Moraska Lafrancois Mark B. Edlund Joy M. Ramstack Hobbs Richard Damstra 《Journal of the American Water Resources Association》2016,52(6):1401-1419
Understanding what constitutes a reference (background) nutrient condition for lakes is important for National Park Service managers responsible for preserving and protecting aquatic resources. For this study we characterize water quality conditions in 29 lakes across four national parks, and compare their nutrient status to U.S. Environmental Protection Agency (USEPA) nutrient reference criteria and alternative criteria recently proposed by others. Where appropriate we also compare the nutrient status of these 29 lakes to state or tribal nutrient reference criteria or standards. For lakes that exceed reference criteria we investigate physical and chemical patterns, and for a subset of lakes compare modern nutrient conditions to paleolimnological (i.e., diatom‐inferred [DI]) nutrient reconstructions. Many lakes exceeded USEPA nutrient reference criteria, but met alternative less restrictive criteria. Modern nutrient conditions were also largely consistent with DI historic (pre‐1900) nutrient conditions. Lakes exceeding alternative nutrient criteria and with elevated nutrient levels relative to DI historic conditions were mostly small, shallow, and dystrophic; continued attention to their nutrient dynamics and biological response is warranted. Coupling modern and paleolimnological data offer an innovative and scientifically defensible approach to understand long‐term nutrient trends and provide greater context for comparison with reference conditions. 相似文献
98.
The dual goals of the Organic Act of 1916 and Wilderness Act of 1964 are to protect natural resources and provide quality
visitor experiences. Park managers need metrics of trail conditions to protect park resources and quality of visitor experiences.
A few methods of sampling design for trails have been developed. Here, we describe a relatively new method, spatially balanced
sampling, and compare it to systematic sampling. We evaluated the efficiency of sampling designs to measure recreation-related
impacts in Rocky Mountain National Park. This study addressed two objectives: first, it compared estimates of trail conditions
from data collected from systematic versus spatially balanced sampling data; second, it examined the relationship between
sampling precision and sampling efficiency. No statistically significant differences in trail condition were found between
the 100-m interval and the spatially balanced datasets. The spatially balanced probability-based dataset was found to be a
good estimate of trail conditions when analyses were conducted with fewer sample points. Moreover, spatially balanced probability-based
sampling is flexible and allows additional sample points to be added to a sample. 相似文献
99.
We conducted a natural resource assessment at two national parks, New River Gorge National River and Shenandoah National Park,
to help meet the goals of the Natural Resource Challenge—a program to help strengthen natural resource management at national
parks. We met this challenge by synthesizing and interpreting natural resource information for planning purposes and we identified
information gaps and natural significance of resources. We identified a variety of natural resources at both parks as being
globally and/or nationally significant, including large expanses of unfragmented, mixed-mesophytic forests that qualify for
wilderness protection, rare plant communities, diverse assemblages of neotropical migratory birds and salamanders, and outstanding
aquatic recreational resources. In addition, these parks function, in part, as ecological reserves for plants in and wildlife.
With these significant natural resources in mind, we also developed a suite of natural resource management recommendations
in light of increasing threats from within and outside park boundaries. We hope that our approach can provide a blueprint
for natural resource conservation at publically owned lands. 相似文献
100.
沈阳市丁香地区土壤重金属污染及生态风险评价 总被引:9,自引:0,他引:9
在丁香公园内设置5个点对土壤中的Cr、Hg、As、Cd、Pb进行含量分析,并用单因子指数法评价土壤污染程度,用Hakanson生态风险指数法对土壤潜在的生态风险进行评价。结果表明,丁香湖公园局部地区Hg、As、Cd超过GB15618-1995一级标准;从总的污染程度看,各污染物从大到小的顺序为:Cd>Hg>Pb>As>Cr,各点位从大到小顺序为:大转弯村>小韩村>丁香苗圃>丁香湖湖区>丁香园小区;从总的潜在生态危险程度看,各个点位的风险程度从高到低依次为:大转弯村>小韩村>丁香苗圃>丁香湖湖区>丁香园小区。 相似文献