Define the major terms essential to the science of ecology and distinguish among the major subfields
- Ecology is the study of the interactions between organisms and their environment and other organisms.
- The biosphere's self-contained nature sets limits on the total resources available, and means human inputs are cycled through different parts.
- It can be subdivided into smaller patches or habitats.
- Ecosystems are comprised of both biotic and abiotic components.
- There are five major levels for studying ecology: physiological (organismal), population, community, ecosystem ecology and landscape ecology.
Describe the abiotic factors that influence life in the biosphere
- Energy is required to drive ecosystems and comes primarily from light, but sometimes from chemicals.
- Water availability and ion concentration and temperature are important limiting factors for most organisms.
- Nutrient availability determines plant growth and therefore food availability to other organisms.
- Fluid flow (wind, currents) can affect rates of exchange, or present an important disturbance regime.
List in order and describe the abiotic factors that determine climate zones across the planet.
Distribution of abiotic factors across the globe help determine climate, and are largely explainable by planetary dynamics
- The most important influence is variation of solar radiation intensity with latitude , producing differential energy input across the planet surface
- The tilt of planet axis relative to plane of orbit produces seasonal changes in energy input
- Differential energy input creates areas of moisture where warm air rises and evaporated water condenses
- The Coriolis effect creates three atmospheric circulation cells in each hemisphere: polar, temperate and tropical zones, as well as the trade winds and doldrums.
- Local conditions are modified by landforms, including continental vs coastal climates, and the rainshadow effect.
Organisms are adapted to abiotic/biotic factors of particular zones, which limits their distribution. Subdivisions of the planet based on typical climate and lifeforms are biomes.
Describe the abiotic and biotic characteristics of the different ocean zones and adjacent biomes.
Marine habitats are the most extensive according to area and volume, but the least explored by humans.
Describe the different types of freshwater biomes and explain how the properties ofa river change between its source and its outlet.
- Aquatic (freshwater) habitats include lakes, ponds, rivers and streams, and show more seasonal variation than marine habitats.
- Running water biomes change with distance downstream from sources. typically:
- temperature increases (and oxygen levels decrease)
- light penetration decreases
- width increases
- speed decreases
- An important zone with both aquatic and terrestrial components are wetlands.
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