Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Ecological resilience wikipedia , lookup
Theoretical ecology wikipedia , lookup
Renewable resource wikipedia , lookup
Ecosystem services wikipedia , lookup
Biological Dynamics of Forest Fragments Project wikipedia , lookup
Biogeography wikipedia , lookup
River ecosystem wikipedia , lookup
Topic 10 The Distribution of Organisms Ecosystem • Recall that an ecosystem is defined as a community of living organisms interacting with each other and the physical environment. • The major categories of components are: – – – – Biota Atmosphere Soil Water Important abiotic factors • Terrestrial ecosystems: – Atmospheric—Light intensity, humidity, precipitation, air temperature – Soil—nutrient availability, moisture, pH, texture and porosity, temperature – Water—precipitation levels, pH • Aquatic ecosystems: – Atmospheric—wind speed and direction, air temperature, light intensity – Water—dissolved nutrients, run-off, precipitation, turbidity, oxygen saturation (DO), water temperature • Marine ecosystems: – Nutrient availability, salinity, air and water temperature, wind speed and direction (influences currents), turbidity, dissolved gases Earth’s Climate Zones Figure 5-2 Terrestrial biome distribution Climate constraints Range of tolerance • Tolerance ranges exist for multiple factors: temperature, pH, light intensity, oxygen or carbon dioxide availability, salinity, etc. • This is closely related to the concept of limiting factors. • The distribution of species is determined by the ranges of abiotic factors present in an area. Gradients • Abiotic factors are not evenly distributed within ecosystems. – Stratification • This leads to micro-habitats within ecosystems Gradients What keeps a species in a place? • Evolutionary constraints • On what level does evolution take place? – Individuals – Populations – Species • What is the mechanism of evolution? Evolution and adaptations Evolution and adaptations Evolution and adaptations