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Though studies have modeled the effects of fires on elk, no studies have related the effects of post-fire landscape succession on ungulate movements and distribution using dynamic modeling techniques. The purpose of this study was to develop and test a spatially-explicit, stochastic, individual-based model (IBM) to evaluate potential movement and distribution patterns of elk (Cervus elaphus nelsoni) in relation to spatial and temporal aspects of the Cerro Grande Fire that burned north central New Mexico in May of 2000. Following extensive literature review, the SAVANNA Ecosystem Model was selected to simulate the underlying post-fire successional processes driving elk movement and distribution. Standard logisitic regression was used to analyze habitat-use patterns of ten elk from data collected using global positioning system radio collars while an additional five animals were used as an independent test set during model validation. Static variables in the form of roads, buildings, fences, and habitual use/memory were used to modify a map of impedance values based on the logistic regression of slope, aspect, and elevation. Integration with SAVANNA came through the application of a habitat suitability index (HSI), which combined movement rules written for the IBM and variables modified and produced by the dynamic ecological processes run in SAVANNA. Overall pattern analysis indicated that realistic migrational processes and habitat-use patterns emerged from movement rules incorporated into the IBM in response to advancing and receding snow when compared to the independent test set. Primary and secondary movement pathways emerged from the collective responses of simulated individuals. Using regression analyses, no significant differences between simulated animals and animals used in either model development or an independent test set revealed any differences in response to snow patterns. These considerations suggest the model was adequately corroborated based on existing data and outlined objectives. 相似文献
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135.
Peng Hu Changsheng Guo Yan Zhang Jiapei Lv Yuan Zhang Jian Xu 《Frontiers of Environmental Science & Engineering》2019,13(4):56
136.
Economic Development,Income Inequality and Environmental Degradation of Fisheries Resources in Mauritius 总被引:1,自引:0,他引:1
Sobhee SK 《Environmental management》2004,34(1):150-157
This article examines how environmental degradation of fisheries resources in the context of Mauritius is linked up with human investment in education, economic growth, and income inequality. Empirical evidence shows that public-sector investment in education promotes economic growth, but at the expense of greater inequality of income. Among the vulnerable groups affected by this type of development process lies the fisherman community. In fact, children of poor families in coastal Mauritius have constrained access to complete school education because of the persistently high opportunity cost involved. Hence, this community is caught up in a vicious circle, as its children or grandchildren would barely be redeployed elsewhere other than in the fisheries sector itself. Such exclusion might account for the overexploitation of marine resources of the island and the accompanying reduction in fish catch over recent years.*(Paper presented at the Third Research and Training Workshop of the Resource Accounting Network for Eastern and Southern Africa (RANESA), University of Pretoria (Funded by SIDA, Sweden), held in Mauritius, Nov 2000. I am grateful to the participants for their helpful suggestions. Needless to say, the usual disclaimer applies).
Published online 相似文献
137.
A new method for predicting vegetation distributions using decision tree analysis in a geographic information system 总被引:4,自引:0,他引:4
Decision tree analysis was used to predict the distribution of forest communities in an area on the south coast of New South
Wales, Australia. The analysis was carried out using a geographical information system environmental data base of those topographic
and geological variables thought to influence the distribution of vegetation and derived from cartographic sources. The resulting
maps of forest communities are of a resolution sufficient to delimit individual forest stands and contain much ecological
information. 相似文献
138.
Robert J. Kalter Lois E. Gosse 《Journal of the American Water Resources Association》1974,10(3):498-511
ABSTRACT: The income redistribution effects of waste water treatment grants are estimated for each state participating in five federal programs. Both gross and net effects per state and per capita are discussed. The impact of the tax structure used to finance such grants and the grant formulae are investigated. 相似文献
139.
田静敏 《中国环境管理干部学院学报》2003,13(1):69-72
教育在社会发展中起能动作用,教师的工资结构应符合社会主义市场经济规律和教师工作特点,实行按劳分配原则,除标准工资外,还要建立等级津贴和特殊工资,从而保证教育人才的稳定和提高,提高教育的国际竞争力。 相似文献
140.
运用数值模拟的方法研究了单喷嘴射流撞击井底时产生的冲击压力及其分布规律。研究结果表明,井底最大冲击压力梯度所在的位置距撞击中心约0.114倍喷距处,井底最大冲击压力梯度和射流喷速成正比,和喷距成反比,本文绘出了其数学表达式。数值计算结果和室内实验数据吻合较为一致。 相似文献