Introduction to Ecology PDF

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Summary

Ecological science basics...

Description

"Studies how an organism's structure, physiology, and behaviour meet the challenges posed by the environment."

"the comprehensive science of the relationship of an organism to its environment" The Biosphere = Is the global ecosystem, the sum of all the planet’s ecosystems Global Ecology = Examines how the regional exchange of energy and materials influences the functioning and distribution of organism across the biosphereFocus is on the global circulation of matter and energy, affecting:-distributions of organisms-changes in populationscomposition of communities-productivity of ecosystem Ecology Oikos = Home or Household + Logos = To Study or Knowledge “The comprehensive science of the relationship of the organism to the environment” Ernest Haeckel (1869) “Scientific study of the distribution and abundance of organisms” (Herbert Andrewartha 1961) “Scientific study of the interactions that shape the distribution and abundance of organisms” (Charles Krebs 1972) Ecology is the scientific study of the interactions between organisms and the environment. These interactions determine both the distribution of organisms and their abundance Ecologists ask a series of questions to determine what factors limit the geographical distribution of any species. What limits a species distribution and abundance?

Ecologists ask a series of questions to determine what factors limit the geographical distribution of any species 1) Abiotic factors Organisms are adapted to a limited set of abiotic factors Therefore non-living chemical and physical factors such as temperature, light, water, and nutrients affect where organisms can live

But the most significant influence on the distribution of organisms on land and in the oceans is climate Four major abiotic components make up climate Temperature, water, sunlight, and wind Climate patterns can be described on two scales Microclimate, very fine patterns, such as those encountered by the community of organisms underneath a fallen log Macroclimate, patterns on the global, regional, and local level

Microclimate Is determined by fine-scale differences in abiotic (and biotic!) factors

This then influences the distribution of organisms on local and regional scales…

Macro climate on a Global scale Earth’s global climate patterns = determined largely by the input of solar energy, the planet’s movement in space and the oceans

Establishes the temperature variations, cycles of air movement, and evaporation of water responsible for latitudinal variations in climate.

Macroclimate on a regional scale Bodies of water and topographic features such as mountain ranges can affect local climates. 1) Oceans and large lakes Moderate the climate of nearby terrestrial environments

2) Mountains have a significant effect on The amount of sunlight reaching an area Local temperature Rainfall, etc

This then influences the distribution of organisms on a Global scales… Biomes = Major types of ecological associations that occupy broad geographic regions of land or water

Biomes-Terrestrial

Biomes-Aquatic

Global biodiversity

Biotic factors The biotic component of an environment is all the other organisms which directly or indirectly affect an organism -

competitors

- predators- prey- many othersOrganisms have significant impacts on other organisms within an environment

Predation

Competition

Dispersal Species dispersal contributes to the distribution of organisms Dispersal is the movement of individuals. It leads to: 1 – distribution of individuals within geographic boundaries 2 – colonisation of new areas Depends on mobility of organism AND availability of habitat (and then suitability of the new habitat) Species transplants/translocations Organisms that are intentionally or accidentally relocated from their original distribution

The Niche It is the set of environmental conditions under which a species can maintain itself, survive and reproduce...