Ch 52: Intro to Ecology and the Biosphere

Ecology Study of the interactions between organisms and the environment Evolution link: Differential survival and reproductive success based on the individual interactions of organisms and their environment lead to evolution

Levels of Organization for Life Atom Molecule Macromolecule Organelle Cell (Tissue, Organ, and Organ system) – depending on the species of organism you are investigating

Levels of Organization for Life Organism Population Community Ecosystem Biosphere Ecology focuses on these last 5 levels

Abiotic Factors Shape Biotic Factors If a single abiotic factor is changed it can have impacts on the whole ecosystem – on both biotic and other abiotic factors Ex: if rainfall amounts change, it can impact the growth of plants and water availability for animals. It can also impact the local climate and weather which can change air temperature

Biomes Terrestrial Biomes: Tropic rainforest Desert Temperate Grasslands Savanna (type of grassland) Temperate Deciduous Forest Taiga Tundra Very large regions of Earth that are defined by the amount of precipitation and temperature of the area Each region has its own dominant vegetation and animal life

Climograph

Aquatic Biomes Freshwater, Marine, and Estuaries Defined by salinity of the water Estuaries – transition zone between a river and the sea and creates a mix of fresh and salt water with the changing of tides

Aquatic Biomes Benthic zone = bottom Organisms that live here can be used as biological indicators meaning that when theses organism’s numbers decrease it can indicate possible pollution issues Photic zone = receives light Aphotic zone = does not receive light

Aquatic Biomes Thermoclines= narrow layers of fast temperature change that separate a warm upper layer of well mixed water and cold deeper waters Thermoclines can influence weather patterns

Freshwater Biomes Oligotrophic lakes = deep lakes that are nutrient- poor and oxygen-rich and contain sparse phytoplankton Often has clear water with high drinking-water quality

Freshwater Biomes Eutrophic lakes = receive high nutrient content from runoff and lower oxygen content with a high concentration of phytoplankton High nutrients cause photosynthetic organisms (algae) to accumulate on the surface Light can’t penetrate down into the lake which causes other producers to die off Detrivores (ex: bacteria) use up oxygen as they decompose the dead organic matter Lower oxygen levels means fish can’t survive

Simple Video Eutrophication and Dead Zone Video