GEOG 310 Lecture Notes - Lecture 4: Ecosystem Services, Species Richness, Primary Production
Document Summary
Variety of life on earth at all scales, ranging from genes to populations within species to species to ecosystems. Richness: measure of the number of unique life forms(e. g species) Evenness: measure of the equitability(e. g relative abundance) among life forms. Heterogeneity: measure of the dissimilarity among life forms. Which community has higher species evenness/which community has higher species richness. So far, about 1. 5-1. 75 million species have been identified. Scientists estimate that there may be between 3 and 117 million species. We can ask how many species are there, and how diverse they are also. Much of the diversity is in the tropical region, declines as we head north. We lose species every day, some that we"ve never found before either. Materials, fluxes and energy between trophic levels and the environment. Energy is taken from the sun, creating glucose and produce tissue for growth. Moderation of hydrologic cycle(organisms can influence water quantity, quality and availability)
