tailieunhanh - From Individuals to Ecosystems 4th Edition - Chapter 22

Chapter 22 Ecological Applications at the Level of Communities and Ecosystems This is the last of the trilogy of chapters dealing with the application of ecological theory. In the first, Chapter 7, we considered how our understanding at the level of individual organisms and of single populations. | Chapter 22 JK Ecological Applications at ft the Level of Communities Tft and Ecosystems Management Based on the Theory of Succession Food Webs Ecosystem Functioning and Biodiversity Introduction This is the last of the trilogy of chapters dealing with the application of ecological theory. In the first Chapter 7 we considered how our understanding at the level of individual organisms and of single populations - related to niche theory life history theory dispersal behavior and intraspecific competition - can provide solutions to a multitude of practical problems. The second Chapter 15 used the theory of the dynamics of interacting populations to guide the control of pests and the sustainable harvesting of wild populations. This final synthesis recognizes that individuals and populations exist in a web of species interactions embedded in a network of energy and nutrient flows. Thus we deal with the application of theory related to succes-si on Chapter 16 food webs and ecosystem functioning Chapters 17-20 and biodiversity Chapter 21 . Community composition is hardly ever static and as we saw in Chapter 16 some temporal patterns are quite predictable. Management objectives on the other hand often seem to require stasis - the annual production of an agricultural crop the restoration of a particular combination of species or the long-term survival of an endangered species. Management will sometimes be ineffective in these situations if managers fail to take into account underlying successional processes see Section . We turn to the application of theory about food webs and ecosystem functioning in Section . Every species of concern application of community and ecosystem theory to managers has its complement of competitors mutualists predators and parasites and an appreciation of such complex interactions is often needed to guide management action see Section . Farmers seek to maximize economic returns by manipulating ecosystems with irrigation and by