Schneider Daniel W
Department of Urban and Regional Planning and Illinois Natural History Survey, University of Illinois at Urbana-Champaign, 611 E. Lorado Taft Drive, Champaign, IL 61820, USA, , , , , , US.
Oecologia. 1997 May;110(4):567-575. doi: 10.1007/s004420050197.
Food web statistics showed a complex relationship with measures of habitat variability in temporary ponds. Connectance was highest in short-duration, highly variable habitats, and lowest in habitats of intermediate duration and variability. The number of links and links/taxon increased with increasing duration. Much of the variation in the food web statistics could be explained by a strong linear relationship between number of taxa and number of links/taxon and a quadratic relationship of taxa number with the number of links. However, after accounting for this variation, there remained a relationship of duration with links and links/taxon. The relationship between the food web statistics and duration corresponded to experimental evaluations of predation in these habitats that showed an increasing importance of predation in long-duration habitats. The food web statistics, however, missed threshold effects in the relationship between predation and habitat duration. Differences in food web statistics before and after a regional drought could be explained by a decrease in taxa number after the drought. Connectance was the most robust statistic in relation to taxa number, but was also the least sensitive to changes in habitat characteristics.
食物网统计数据显示出与临时性池塘栖息地变异性指标之间存在复杂的关系。连通性在持续时间短、变异性高的栖息地中最高，而在持续时间和变异性处于中等水平的栖息地中最低。连接数和连接数/分类单元数随着持续时间的增加而增加。食物网统计数据中的大部分变异可以通过分类单元数与连接数/分类单元数之间的强线性关系以及分类单元数与连接数之间的二次关系来解释。然而，在考虑了这种变异之后，持续时间与连接数和连接数/分类单元数之间仍然存在关系。食物网统计数据与持续时间之间的关系与这些栖息地中捕食作用的实验评估结果相符，该评估表明捕食作用在持续时间长的栖息地中越来越重要。然而，食物网统计数据忽略了捕食与栖息地持续时间之间关系中的阈值效应。区域干旱前后食物网统计数据的差异可以用干旱后分类单元数的减少来解释。连通性是与分类单元数相关的最稳健的统计量，但对栖息地特征变化也是最不敏感的。
