unit 1 environmental science cape :)

• Ecology


  The study that deals with the relationships of organisms (species) to one another and their interactions with their physical surroundings
• Species


  A group of organisms that are genetically similar and interbreed with one another to produce live, fertile offspring
• Population


  All members of a species living in a given area at the same time
• Community


  All of the populations of organisms living and interacting in a particular area
• Ecosystem


  All of the populations in a given area (biological community) together with the nonliving components
• Levels of biological organisation

  • Atom
  • Molecule
  • Cell
  • Tissue
  • Organ
  • System
  • Organism
  • Population
  • Community
  • Ecosystem
  • Biosphere
• Biological communities are limited by biological or biotic factors such as predators and available food resources
• Autotrophs


  Organisms that make their own food by photosynthesis (producers)
• Consumers


  • Herbivores
  • Carnivores
  • Omnivores
  • Detritivores
• Decomposers are important in recycling of nutrients
• Ecological succession


  1. Initial colonisation

  2. Replacement by other species (Competition, natural selection, habitat changes)

  3. Development of a stable species distribution and habitat
• Biosphere


  The part of the Earth that supports all life
• Atmosphere


  The layer of air that surrounds the planet Earth
• Hydrosphere


  The part of the Earth that is composed of all of the water on or near the Earth
• Lithosphere


  The Earth's interior, rocks, soil
• The biosphere, atmosphere, hydrosphere and lithosphere are four interconnected parts that form a system
• Conduction, convection and radiation are responsible for transferring energy between the Earth's surface and the atmosphere
• The hydrosphere is always moving. Water in rivers flows to oceans and seas. The water in seas and oceans moves because of the action of the wind, which creates waves, currents and tides
• Biomes are defined on the basis of climate, geography and the species native to the region
• Aquatic biomes


  • Freshwater biomes (ponds, lakes, streams, rivers, wetlands)
  • Marine biomes (oceans, coral reefs, estuaries)
• Estuaries are areas where there is mixing of fresh water and marine water. These areas are described as being brackish
• The Earth is divided into three layers: the crust, the mantle and the core
• Two types of lithospheric crust are identified: continental crust and oceanic crust
• Freshwater biomes


  Areas of low salt content, cannot survive in high salt content marine regions
• Estuaries


  Areas where there is mixing of fresh water and marine water, described as brackish, support diverse flora and fauna
• Coral reefs


  Distributed in warm, shallow waters, may be found as barriers along continents or as fringing islands and atolls
• Layers of the Earth

  • Crust
  • Mantle
  • Core
• Lithosphere


  • Outermost layer is made up of the lightest material, innermost layers are made up of the densest materials
  • Crust is approximately 1% of the Earth's mass
  • Mantle is approximately 66% of the Earth's mass
  • Core is approximately 33% of the Earth's mass
• Continental crust


  Composition similar to granites
• Oceanic crust


  Composition similar to basalt, denser than continental crust
• The hydrosphere is that part of the Earth that is composed of all of the water on or near the Earth
• All living organisms are components of the biosphere, which is divided into biomes
• Main types of biomes

  • Aquatic
  • Desert
  • Forest
  • Grassland
  • Tundra
• Vegetation types are very useful when describing different biomes
• Physical layers of the Earth

  • Lithosphere
  • Asthenosphere
  • Mesosphere
  • Outer core
  • Inner core
• Habitat


  The place where a particular organism lives, characterised by a set of specific environmental conditions
• Niche


  The role that a species plays in a community, includes its habitat, food resources, use of abiotic resources, how it is influenced by abiotic factors, and how it interacts with other individuals
• Niche and habitat are not the same thing, many species share a habitat but every species has a unique niche
• Fundamental niche


  The set of favourable conditions determined by abiotic and biotic variables where the species can survive and successfully reproduce
• Realised niche


  The part of the fundamental niche actually occupied by the species, given the presence of other species competing for the same resources