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Phong cảnh và Edge Tác dụng trên Dynamics Dân số: Phương pháp tiếp cận và Ví dụ Giới thiệu Metapopulations Các loại Dynamics phân phối hiệu ứng không gian của Habitat gạch nối giữa Dân số hiệu ứng hành vi Töông cộng đồng tại Edges hiệu ứng khác nhau bổ cảnh quan không gian Scales hoặc bổ sung hiệu ứng Khoảng cách ngắn ảnh hưởng cảnh quan quy mô thật Cân không gian lớn hơn Một số khái quát hạn chế tiến hóa và tính không đồng nhất Bối cảnh lịch sử hoặc Sinh Thái Cảnh Quan? . | 6__ Landscape and Edge Effects on Population Dynamics Approaches and Examples Lennart Hansson CONTENTS Introduction Metapopulations Types of Dynamics Spatial Distribution Effects of Habitat Juxtaposition Population Effects Community Interactions Behavior at Edges Effects at Various Spatial Scales Landscape Complementation or Supplementation at Short Distance Effects at the True Landscape Scale Effects at Larger Spatial Scales Some Limited Generalizations Evolutionary and Historical Background Heterogeneity or Landscape Ecology How to Test Landscape Effects Landscape Ecology and Conservation Acknowledgments Introduction Until the early 1980s population dynamics were almost always modeled conceptually or mathematically for a homogeneous area without any edge. However most habitat patches are small particularly with regard to wide- 2000 by CRC Press LLC ranging vertebrates and edge effects are indeed common. It is surprising that field ecologists did not object to this unrealistic representation of nature until 10 to 15 years ago. There was a gradual change in the late 1980s and a more pronounced one in the 1990s particularly with the re-apprehension of the metapopulation approach. And during the 1990s the theoreticians have again found a new playground now starting to model effects of environmental heterogeneity. However the early observations about suprahabitat or landscape effects Levins 1969 Anderson 1970 Hansson 1977 Wegner and Merriam 1979 were usually not sympathetic to traditional theory. In this chapter I will look at dynamics in heterogeneous areas usually the landscape scale as discussed later with two or several ecosystems from a field biologist s rather than a theorist s point of view. Landscape composition has various influences on populations of mobile organisms. So far mainly animals have been considered but effects on plant propagules ought also to be examined. Furthermore nonrandomly distributed mobile herbivores .