生物学导论biology15.ppt

Chap 15 Community Interactions;Contents;Key terms;15.1 Community, Habitat, and Niche;Habitat (栖息地): the kind of place, or part of an ecosystem, occupied by an organism Niche (生态位): the specific functional role of an organism某一生物单元在生态系统中的功能地位 ;Opossum with broad niche;15.2 Kinds of organism interactions;Predation (捕食);Individual that was killed was harmed, but Population benefits: predators help to maintain feasible population size of prey Species benefits: predators act as selecting agents;Parasitism (寄生);Parasitism (寄生);Parasite Vector (带菌者):organism carrying a disease from one individual to another, bacterium Yersinia pestis 鼠疫杆菌 ;;Grass predators, or herbivore: cow — grass Some live on the host temporary Nest parasitism: cowbird and cuckoo;Commensalism (共栖);Mutualism (互利共生);Competition (竞争);Butterfly-ant interlivings ;15.3 The cycling of material in ecosystems;The carbon cycle (碳循环);The carbon cycle;The hydrologic cycle (水循环);The hydrologic cycle;The nitrogen cycle (氮循环);亚硝酸盐;The phosphorus cycle (磷循环);沉淀物;15.4 The impact of human actions on communities;Introduced species;Predator control;Habitat destroy;Pesticide use;Biomagnification;Summary