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151.
S.B.C. Bisceglia J.A. Pereira P. TetaR.D. Quintana 《Journal of Arid Environments》2011,75(11):1024-1028
Small mammals usually constitute the main prey for Leopardus geoffroyi throughout its distribution. We studied the patterns of small rodent selection by this felid in a semi-arid scrubland of central Argentina, addressing whether prey choice may be related to the availability, morphology, and distribution of the different rodent species. Cat’s diet was studied during 2005-2006 through the analysis of 182 scats, along with field estimates of rodent abundances from trapping. The cricetine rodents Akodon molinae and Calomys musculinus were predated according to the availability expected by trapping, indicating that their use was opportunistic. Akodon azarae and Graomys griseoflavus, on one hand, and Eligmodontia typus, on the other hand, were consumed in lower and higher proportion than their availabilities, respectively. Our results suggest that some cricetine rodent characteristics such as abundance, escape ability, microhabitat use, and activity period, appear to be potential factors contributing to differential vulnerability to predation by Geoffroy’s cat in central Argentina. 相似文献
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《The Professional geographer》2013,65(2):222-223
Abstract The combination of detailed sample data with less detailed but fully enumerated marginal subtotals is the focus of a wide range of research. In this article we advocate careful modeling of sample data, followed by Iterative Proportional Fitting (IPF). The modeling aims to estimate accurately the interaction or odds ratios of complex tables, which is information not contained in the marginal subtotals. IPF ensures consistency with the subtotals. We advance this work in three practical ways. First, we show that detailed small-area estimates of both counts and proportional distributions usually gain accuracy by combining data for larger areas containing the small areas, and we illustrate the multilevel framework to achieve these estimates. Second, we find that a general classification or socioeconomic typology of the small areas is even more associated with the within-area interactions than is membership of the larger area. Third, we show how the Statistical Package for the Social Sciences (SPSS) can be used for IPF in any number of dimensions and with any structure of constraining marginal subtotals. Throughout, we use an example taken from the 1991 U.K. Census. These data allow us to evaluate various methods combining 100 percent tabulations and the Samples of Anonymised Records. 相似文献
155.
NIGEL WALFORD 《International journal of geographical information science》2013,27(7):749-767
This paper reports on the outcome from a project that has developed a GISbased procedure to capture digital boundaries for the small spatial units used in the British Population Census in 1981, and for the geographically comparable units connecting back with the previous enumeration in 1971. 1981 census geography was originally recorded as linear and textual annotations on paper base maps that were subsequently microfilmed. Four methods involving varying degrees of automation for capturing digital representations of these census units from the scanned microfilm imagery are evaluated. Details presented are in the context of British census geography before digital capture of small census units became routine, but the evaluation of the methods and the final procedure cover issues that are generally applicable in situations where the capture of historical mapping is attempted. 相似文献
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新疆数字测震台网的监测能力及其构造意义 总被引:3,自引:0,他引:3
新疆地震监测台网从1970年前的4个台发展到2008年数字测震台网建设完成以后,共有测震台站63个,结合邻省的15个地震台站的实时数据,地震监测能力得到极大的提高。阿勒泰构造小区、西准噶尔小区、北天山西段、南天山东段和西段现今的地震监测能力为1.5~2.0级,东天山为2.0~2.5级,西昆仑、阿尔金和交汇区为2.5~3.0级,乌鲁木齐和喀什附近地区的现今监测能力为0.5~1级。新疆数字测震台网的建设着重考虑了对新疆活动构造的监测,目前对新疆大部分活动断裂带的监测能力都在1.0~1.5级,这对今后的地震监测预报和防震减灾工作有十分重要的意义。 相似文献
158.
呼图壁地下储气库部分区域地表垂直形变机理研究 总被引:1,自引:0,他引:1
利用在呼图壁地下储气库开展的2013~2015年7期二等水准测量获得的高差数据,对由于地表气井压力变化影响而发生的地下储气库地表垂直变形进行了分析。研究表明,呼图壁地下储气库区的地表变形除了构造成因引起的盆地下沉以外,其他主要形变成因来源有2个方面:一个是呼图壁地区的地下水超采影响着该地区的地表垂直变化;另一个是储气库集采气期间井口压力变化影响下的地表沉降,根据计算,储气库每MPa气井压力变化影响到的地表变化约为0.625~1.125mm。 相似文献
159.
Julian Clifton Michelle EtienneDavid K.A. Barnes Richard S.K. Barnes David J. SuggettDavid J. Smith 《Marine Policy》2012,36(3):823-831
The marine assets of Seychelles are fundamental to the national economy through generating income derived from tourism and fisheries. Marine management institutions and policies have undergone radical changes since 2008, reflecting a number of drivers and initiatives at international and national levels. Through using the example of Curieuse Marine National Park in the inner Seychelles, we demonstrate how these are affecting marine conservation with respect to coastal development, governance of marine protected areas and livelihood security within resource-dependent communities. These issues are of significance with respect to the current and future viability of marine conservation and resource management in Seychelles. Potential mitigating strategies are suggested which could lead to more effective governance and conservation of marine protected areas in Seychelles and similar small island developing states. 相似文献
160.
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????PS-InSAR??SBAS-InSAR??????????????????????????????2004??2010???31??ENVISAT ASAR??????????????????????????????????????PS-InSAR??SBAS-InSAR?????????к?????????Щ??????????????SBAS-InSAR??PS???α??????????????????????????????????????????????е????????????????????????????????????????????? 相似文献