ENV100Y5 Lecture Notes - Lecture 28: Ecotourism, Mescaline, Soil Fertility

• School: UTM
• Department: Environment
• Course: ENV100Y5
• Professor: Barbara Murck

Document Summary

Organisms provide drugs and medicines: plants, in response to herbivory, produces, cyanide, caffeine, cocaine, mescaline, nicotine and many more. Biodiversity helps maintain ecosystem funcitons: biodiversity increases the stability and resilience of communities and ecosystems, decreased biodiversity reduces natural system"s ability to function and provide services. Ways we measure species diversity: abundance, number of individuals, richness, number of different species, evenness, distribution of abundance over species. Generalists and specialists: if species are mostly generalists, -diversity is low, ex. Leopard frog: found in lakes, rivers, ponds, streams, wetlands, if species are mostly specialists, -diversity is high, ex. Tailed frog: only in cold, clear mountain streams sensitive to siltation, warming. Factors that drive species richness: spatial factors, area size, proximity, fragmentation & isolation, climatic factors, productivity & predictability, historical factors, evolutionary time. Spatial factors that drive species richness: area size and proximity, species-area curve the island model, large islands contain more species than small islands.