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1.
Forage availability for mule deer (Odocoileus hemionus) in the Sonoran Desert depends on plant biomass, which is influenced by rainfall. We determined how rainfall, temperature and plant characteristics affected biomass of deer forage. We measured forage biomass, rainfall and temperature every 3 months from April 2000 to December 2002. Quarterly rainfall ranged from <1 to 57 mm, and forage biomass in desert washes fluctuated between 6 and 34 g m−2. There was a positive relationship between forage biomass and rainfall the previous six months (p<0.001), and a negative relationship between biomass and average temperature the previous 3 months (p<0.001). Quarterly forage growth was positively influenced by rainfall (p<0.001) and negatively influenced by forage biomass (p<0.001). The relationships between deer forage and environmental factors established here will be useful in understanding population ecology of mule deer as part of an interactive model of plant–herbivore dynamics in arid environments.  相似文献   
2.
Sagebrush ecosystems of the western US provide important habitat for several ungulate and vertebrate species. As a consequence of energy development, these ecosystems in Wyoming have been subjected to a variety of anthropogenic disturbances. Land managers require methodology that will allow them to consistently catalog sagebrush ecosystems and evaluate potential impact of proposed anthropogenic activities. This study addresses the utility of remotely sensed and ancillary geospatial data to estimate sagebrush cover using ordinal logistic regression. We demonstrate statistically significant prediction of ordinal sagebrush cover categories using spectral (χ2 = 113; p < 0.0001) and transformed indices (χ2 = 117; p < 0.0001). Both Landsat spectral bands (c-value = 0.88) and transformed indices (c-value = 0.89) can distinguish sites with closed, moderate and open cover sagebrush cover categories from no cover. The techniques described in this study can be used for estimating categories of sagebrush cover in arid ecosystems.  相似文献   
3.
谈耀麟 《矿产与地质》1992,6(6):487-491
ENCORE钻孔导斜系统由设计先进的MOLE型固定楔、MULE型活楔、RATTY型扩孔导向矛和DOLPHIN型定向仪组成。可在40-96mm钻孔中进行定向钻进,解决钻孔纠斜或分支孔钻进问题。在分析研究其、工作原理和操作方法基础上进行对比分析,指出优点并介绍了使用效果。  相似文献   
4.
Deer–vehicle collisions (DVCs) are a constant problem in North America that cost millions of dollars of damage and loss of human life. This study investigated the spatial relationship of DVCs for a county in western Indiana using nearest neighbor analysis, chi-square test of independence, and a landscape metric: the percentage of like adjacencies. The study was able to show that DVCs are not randomly located, and that habitat type and structure may play an important role in the location of DVCs.  相似文献   
5.
对旅游流时空演变规律的研究,有助于揭示旅游系统内部各要素间相互作用的过程和机理。本文采用K-Means聚类法对盐城麋鹿生态旅游区游客数进行时空聚类,分别从省内和国内(省际)两个尺度上讨论了麋鹿生态旅游区游客变化的阶段性和市场划分,结果表明,1998~2005年间省内旅游流和国内(省际)旅游流从时间上可分为三个阶段,并较好地划分出了四种不同的客源地类型。根据时空聚类中不同类别中心点的变化,详细论述了麋鹿生态旅游区省内和国内(省际)旅游流随时间和空间变化的规律,揭示了不同类别之间旅游流整体变化特征,可为旅游规划、产品开发、市场营销以及旅游区的运营、管理和决策提供依据。K-Means聚类法能够从不同尺度上揭示旅游流时空变化的详细信息,可作为旅游流时空分布与演化特征分析的有效工具和手段。  相似文献   
6.
Using microhistological analysis of faeces, we studied the diets of the wild Chacoan Brown brocket deer (Mazama gouazoubira) and the exotic European hare (Lepus europaeus) by comparing plant species frequency in faeces with plant species availability. Research was conducted in the dry southern portion of South American Chaco, in forests subjected to livestock ranching in the north of Córdoba province, Argentina. The diet of the Brown brocket deer was more closely related to forage availability (C=0.82195) than the diet of the European hare (C=0.38565). Dicots comprised 90% of the Brown brocket deer diet and were preferred throughout the year, while gramineous species were consumed in low amount. In the diet of the European hare, gramineous species were frequent (65 to 87%) and preferred in every season but in winter, when dicots were consumed in higher proportions (92%). Differences in feeding habits and in habitat use would allow both herbivores to coexist; however, probable competition for food with the European hare during the dry period, in addition to habitat loss, threatens survival of the Brown brocket deer.  相似文献   
7.
The 150‐year history of red deer in New Zealand reflects changing relations between people and introduced animals and has involved recreational, environmental and commercial hunting. Hunters initially pursued red deer for recreation then for environmental control before the animals were subsumed into society's economic processes. After 1930, they were regarded as environmental pests and hunting was open to all. Commercial hunting started after World War II, when economic value redefined the relationship between red deer and people. Relations between people and red deer continued to evolve as New Zealanders generated progressively more refined understandings of nature and the place of introduced species in this country's diverse environments.  相似文献   
8.
黄震方  袁林旺  俞肇元 《地理学报》2007,62(12):1277-1286
生态旅游区的发展受到诸多确定性因素和随机性因素的共同作用,并反映于旅游区游客观测序列。通过构建游客序列分析框架,提出了游客序列分析的理论模型。并以江苏盐城麋鹿生态旅游区为例,集成多种数学方法,进行了游客序列的分解、调整和综合预测的实证 分析。运用Tramo/Seats 方法进行季节调整分析可有效提取时间序列各组分,从而获得了不同尺度的作用模式,所获得的去噪序列为预测研究提供了基础资料。基于ARIMA 模型、Winter 加法模型、Winter 乘法模型和Tramo/Seats 模型的综合预测表明,麋鹿生态旅游区未来两年年平均新增游客数量在1.95-3.14 万人次之间。各方法预测结果间的差异与其建模思路及实现方法有关,因此集成多种方法进行预测,并进行对比分析,有助于获得对游客波动变化更为全面的认识,同时所提供的多种可能预测方案,可为生态旅游区容量控制、旅游环境资源的保护与开发及旅游区的管理决策提供参考依据。  相似文献   
9.
To aid the effectiveness of water developments, patterns of deer visiting water sources and the responses of deer to disturbance were examined. Deer visited water sources day and night, but not all deer at water sources drank. Thus, the assumption that radio-telemetry locations within arbitrary distances of water indicate drinking events may lead to overestimates of watering frequency. Human disturbance did not preclude or seriously impede use of water by deer. Deer reacted by adjusting the amount of time spent at water sources, moving away from water to return later and/or increasing the frequency with which they drank.  相似文献   
10.
对旅游流时空演变规律的研究,有助于揭示旅游系统内部各要素间相互作用的过程和机理。本文采用K-Means聚类法对盐城麋鹿生态旅游区游客数进行时空聚类,分别从省内和国内(省际)两个尺度上讨论了麋鹿生态旅游区游客变化的阶段性和市场划分,结果表明,1998~2005年间省内旅游流和国内(省际)旅游流从时间上可分为三个阶段,并较好地划分出了四种不同的客源地类型。根据时空聚类中不同类别中心点的变化,详细论述了麋鹿生态旅游区省内和国内(省际)旅游流随时间和空间变化的规律,揭示了不同类别之间旅游流整体变化特征,可为旅游规划、产品开发、市场营销以及旅游区的运营、管理和决策提供依据。K-Means聚类法能够从不同尺度上揭示旅游流时空变化的详细信息,可作为旅游流时空分布与演化特征分析的有效工具和手段。  相似文献   
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