...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Biogeography >The effect of the extent of the study region on GIS models of species geographic distributions and estimates of niche evolution: preliminary tests with montane rodents (genus Nephelomys) in Venezuela
【24h】

The effect of the extent of the study region on GIS models of species geographic distributions and estimates of niche evolution: preliminary tests with montane rodents (genus Nephelomys) in Venezuela

机译：研究区域范围对物种地理分布的GIS模型和生态位演化的估计的影响：委内瑞拉的山地啮齿动物（Nephelomys属）的初步测试

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

AimVarious techniques model a species' niche and potential distribution by comparing the environmental conditions of occurrence localities with those of the overall study region (via a background or pseudoabsence sample). Here, we examine how changes in the extent of the study region (ignored or under-appreciated in most studies) affect models of two rodents, Nephelomys caracolus and Nephelomys meridensis.LocationNorth-central South America.MethodsWe used Maxent to model the species' potential distributions via two methods of defining the study region. In Method 1 (typical of most studies to date), we calibrated the model in a large study region that included the ranges of both species. In Method 2, we calibrated the model using a smaller study region surrounding the localities of the focal species, and then applied it to the larger region. Because the study region of Method 1 is likely to include areas of suitable conditions that are unoccupied because of dispersal limitations and/or biotic interactions, this approach is prone to overfitting to conditions found near the occupied localities. In contrast, Method 2 should avoid such problems but may require further assumptions ('clamping' in Maxent) to make predictions for areas with environmental conditions beyond those found in the smaller study region. For each method, we calculated several measures of geographic interpredictivity between predictions for the species (cross-species AUC, cross-species omission rate, and proportional geographic overlap).ResultsCompared with Method 1, Method 2 revealed a larger predicted area for each species, less concentrated around known localities (especially for N. caracolus). It also led to higher cross-species AUC values, lower cross-species omission rates and higher proportions of geographic overlap. Clamping was minimal and occurred primarily in regions unlikely to be suitable.Main conclusionsMethod 2 led to more realistic predictions and higher estimates of niche conservatism. Conclusions reached by many studies depend on the selection of an appropriate study region. Although detailed information regarding dispersal limitations and/or biotic interactions will typically be difficult to obtain, consideration of coarse distributional patterns, topography and vegetational zones often should permit delimitation of a much more reasonable study region than the extremely large ones currently in common use.
机译：AimVarious技术通过将发生地点的环境条件与整个研究区域的环境条件进行比较（通过背景或假性样本）来对物种的生态位和潜在分布进行建模。在这里，我们研究了研究区域范围的变化（在大多数研究中被忽略或未得到充分认识）如何影响两种啮齿动物的模型，即南海豚鼠（Nephelomys caracolus）和北海豚鼠Nephelomys meridensis。通过两种定义研究区域的方法进行分布。在方法1（迄今为止大多数研究的典型方法）中，我们在一个包括两个物种的范围的大研究区域中对模型进行了校准。在方法2中，我们使用围绕焦点物种所在位置的较小研究区域对模型进行了校准，然后将其应用于较大区域。由于方法1的研究区域可能包括由于分散限制和/或生物相互作用而未被占用的合适条件区域，因此该方法很可能过度适合在所占位置附近发现的条件。相比之下，方法2应该避免此类问题，但可能需要进一步的假设（在Maxent中为“钳位”），以对环境条件超出较小研究区域的区域进行预测。对于每种方法，我们计算了该物种预测之间的几种地理相互预测性度量（跨物种AUC，跨物种遗漏率和成比例的地理重叠）。结果与方法1相比，方法2揭示了每种物种更大的预测面积，较少集中在已知地区周围（尤其是卡拉科鲁斯猪笼草）。这还导致更高的跨物种AUC值，更低的跨物种遗漏率和更高的地理重叠比例。主要结论方法2导致对生态位保守主义的预测更加现实，且估计值更高，主要发生在不太适合的地区。许多研究得出的结论取决于选择合适的研究区域。尽管通常将很难获得有关扩散限制和/或生物相互作用的详细信息，但考虑到粗略的分布模式，地形和植被区域，通常应该比目前使用的非常大的区域划定一个更加合理的研究区域。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号