Ecosystem Dynamics What is ecology? Study of the interactions between parts of the environment Connections in nature Abiotic: soil comp. Biotic: and Abiotic and Biotic factors factors in the environment ex. Rainfall, light, factors in an environment Ex. Trees, insects, mammals Organization of Ecosystems Organism- basic unit of ecology; only one Species Two or more organisms that are the same and can Resemble each other in appearance, chemistry, and genes An area over which we can find a species is called its How Many Species are on Earth? Around million species have been cataloged and identified There are probably 10-15 million species on earth with estimates as high as a 100 million Most species are Which species run the world? Bacteria, protozoa, fungi and yeast(microbes) Account for of the earth's living biomass Populations A group of organisms of one species living in the place at the time that interbreed Niche: day Niche and Habitat a species plays in a community. What it does all
Habitat- place where an organism Range of Tolerance Every population thrives in an range of abiotic factors. Beyond this range, there are less and less numbers of these organisms. In an ecosystem, it is harder to represent what this optimal range is, since a host of factors affect the survivability of this population. Often, the range is shown for each factor, and this is known as the Organisms and their changing environment Acclimation - Some organisms can to abiotic factors through the process of acclimation. Control of Internal Conditions - Conformers are organisms that do not regulate their internal conditions; they change as their external environment changes. - Regulators use energy to control some of their internal conditions. Escape from Unsuitable Conditions - Some species survive unfavorable environmental conditions by becoming Limiting factors Limiting Factor: anything that tends to make it more difficult for a species to live and grow, or reproduce in its environment temperature water climate/weather soils (mineral component) competition: interspecific and intraspecific predation/parasitism mutualism Community A collection of several populations that live and interact. If one population increases the other may decrease Ecosystem: Interaction between the living and nonliving parts of an area
Biome Entire community of living organisms that live in a Determined by temperature, precipitation, latitude, elevation and global wind patterns Biosphere All the areas on the planet that contain life Everything is related to everything- interdependence Earth's life support systems Biosphere - Atmosphere troposphere stratosphere mesosphere thermosphere - Hydrosphere - Liquid water - Ice - Water vapor Biosphere - Lithosphere - Crust - mantle Types of Organisms make their own food (green plants, bacteria, algae) Photosynthesis- Heterotrophs Must get their They can not make it themselves. Herbivores Primary consumer Eat Types of Heterotrophs Carnivore Eat herbivores Secondary consumer from something else.
Heterotrophs Secondary and tertiary consumers Omnivore Eat plants and animals Pigs, rats, foxes, bears, humans, bears Decomposers Breakdown nutrients into ecosystem Clean environment Slime mold/fungus/bacteria Consumers Eat Clean up environment insects Detritivore/Scavenger animals or wastes of animals Aerobic/Anaerobic Respiration In most cells, energy is released by respirationrequires Some decomposers get their energy through anaerobic respiration does not require Tracing the flow of energy through an ecosystem Always begins with the and is followed by an autotroph Food web- a complex system of in an ecosystem Trophic levels-a group of organisms that occupy the same position in a food chain Ecological pyramid-a designed to show the relationship between energy and trophic levels of a given ecosystems: produces on bottom
Producer Primary consumer Secondary consumer Tertiary consumers Decomposers Rarely more than Trophic levels General Terms Biomass-dry weight of all contained in its organisms Ecological efficiency -A measure of the amount of energy in the biomass that is produced by one trophic level and is passed on to the biomass produced by the next (higher) trophic level. Gross primary Productivity(GPP) -the rate at which an ecosystems producers into chemical energy Net Primary Productivity(NPP)- measures how fast producers needed by other consumers in an ecosystem. NPP=GPP-R The planets NPP ultimately limits the number of consumers( including humans)that can survive on earth Water Cycle Effects of Humans on the Water Cycle 1) We withdraw large quantities of freshwater from lakes, rivers, aquifers, and streams sometimes at rates than it is replenished 2) We clear vegetation from land and sometimes cover the ground with concrete, asphalt and buildings. This reduces of water, increases flood risk, increases run off etc.
3) We add phosphates, nitrates and other pollution into our water making it 4) increased warming of atmosphere has increased speed of water cycle which could change rainfall patterns Effects of Human Activities on the Carbon Cycle 1) we clear that absorb CO2 2) we add a lot of by burning fossil fuels and wood These interactions could increase the natural greenhouse effect and thereby increase global warming. Global warming could change weather patterns, disrupt global food production, disrupt wildlife habitats etc. Effects of Human Activities on the Nitrogen Cycle 1) we add large amounts of (NO) into the atmosphere when Nitrogen and oxygen combine as we burn any fuel at high temperatures. Returns to earth as 2) we add nitrous oxidefnao) to the atmosphere through the action of on livestock wastes and commercial inorganic fertilizers. Can warm atmosphere and deplete ozone 3) ions in inorganic fertilizers can leach through soil and contaminate groundwater 4)We release large amounts of nitrogen stored in soils and plants as gaseous compounds into the troposphere through destruction of forests, grasslands, and wetlands 5) We upset aquatic ecosystems by adding excess nitrates into bodies of water through sewage and agricultural runoff 6) We remove nitrogen from topsoil when we harvest nitrogen rich crops
Effects of Human Activities on the Phosphorus Cycle 1) we mine large quantities of phosphate rock to make commercial inorganic fertilizers and some detergents 2) we reduce the available phosphate in tropical soils when we cut down areas of tropical forests 3) We disrupt aquatic systems with phosphates from runoff of animal wastes and fertilizers and discharges from sewage treatment systems Effects of Human Activities on the Sulfur Cycle 1) we burn sulfur containing coal and oil to produce electric power 2) we refine sulfur containing petroleum to make gasoline, heating oil and other useful products ) we convert sulfur containing metallic mineral ores into free metals such as Cu, Pb, Zn- an activity that increases the amount of sulfur dioxide into the environment