Briers R A, Warren P H
Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK, , , , , , GB.
Oecologia. 2000 May;123(2):216-222. doi: 10.1007/s004420051008.
Simple metapopulation models assume that local populations occur in patches of uniform quality habitat separated by non-habitat. However field metapopulations tend to show considerable spatial and temporal variation in patch quality, and hence probability of occupancy. This may have implications for the adequacy of simple metapopulation models in describing and predicting regional population dynamics of natural systems. This study investigated the effects of habitat characteristics on landscape-scale occupancy dynamics of two species of backswimmer (Notonecta, Hemiptera: Notonectidae) in small freshwater ponds. The results demonstrated clear links between habitat, pond occupancy and population turnover, particularly local extinction. There were considerable changes in the habitat of individual ponds between years, but local changes were not spatially correlated and the frequency distribution of habitat conditions at the landscape level remained similar in different years. Stable occupancy levels of Notonecta species appears to result from a balance of the rates of creation and loss of suitable habitat due to spatially uncorrelated habitat change. Systems such as this, where turnover is driven by habitat dynamics, demonstrate the potential value of incorporating the dynamics of habitat change into metapopulation models. Such developments are likely to improve predictions of landscape-scale occupancy dynamics, whilst also allowing patch-level predictions of occupancy, based on local habitat conditions.
简单的集合种群模型假设，局部种群出现在由非栖息地分隔的质量均匀的栖息地斑块中。然而，实地的集合种群往往在斑块质量以及因此在占据概率方面表现出相当大的空间和时间变化。这可能会影响简单集合种群模型在描述和预测自然系统区域种群动态方面的充分性。本研究调查了栖息地特征对小型淡水池塘中两种仰泳蝽（仰泳蝽属，半翅目：仰泳蝽科）景观尺度占据动态的影响。结果表明了栖息地、池塘占据和种群更替之间的明确联系，尤其是局部灭绝。各年份间单个池塘的栖息地有相当大的变化，但局部变化在空间上不相关，并且不同年份景观水平上栖息地条件的频率分布保持相似。仰泳蝽物种稳定的占据水平似乎是由于空间上不相关的栖息地变化导致适宜栖息地的创建和丧失速率之间达到平衡的结果。像这样由栖息地动态驱动更替的系统，证明了将栖息地变化动态纳入集合种群模型的潜在价值。这样的发展可能会改善对景观尺度占据动态的预测，同时还能基于局部栖息地条件对占据情况进行斑块水平的预测。
