Conditions Resources in Relation to Distribution and Abundance 1 Basic Terms a Biotic pertains to living portions of environments i e other organisms such as o competitors o predators o viruses o any living form b Abiotic pertains to non living aspects of environments i e physical or chemical factors or dead organic matter such as o light o temperature o dead organic matter c Condition a non consumable environmental factor i e present in unlimited quantity d Resource a consumable environmental quantity 2 Combinations of basic terms i e present in limited quantity a Abiotic condition e g temperature b Abiotic resource e g for many plants light c Biotic condition e g vegetative structure for predatory birds EX Accipiter hawks use vegetation to hide themselves while approaching prey d Biotic resource e g voles rodents captured and ingested by predatory birds EX Peregrine falcons eat pigeons 3 Attributes of resources a Potential effect on survival and reproduction i e part of ecological environment Factor must have an impact b Must be consumed Ingested needed for normal physiology e g food and reproduction e g nest sites c Consumption should reduced resource s availability to other individuals At the heart of competition Consumption leaves less for yourself conspecifics and members of other species 4 Effects on distribution and abundance a Notion of limiting factors Factors operate at edge of range to limit spatial distribution Factors operate within range to restrict local distribution b Conditions and resources can interact o restrict distributions c Other considerations are important i e dispersal habitat choice Dispersal movement of organisms typically between place of birth and place of reproduction Habitat choice behavioral choice of where to live and where not Conditions and resources are not the whole story about limiting to live factors
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