Cycles in Nature Ecosystems Ecosystems change over time and depend on the cycling of matter. Matter Matter on Earth is limited; therefore, it is used over and over. Each type of matter has its own cycle. Nutrient Cycles Cycling maintains homeostasis (balance) in the environment. 3 cycles to investigate: 1. Water cycle 2. Carbon cycle 3. Nitrogen cycle Water cycle- Evaporation, transpiration, condensation, precipitation Water cycle- Carbon cycle- Photosynthesis and respiration cycle carbon and oxygen through the environment. Carbon cycle- Photosynthesis & Respiration Photosynthesis Plants absorb Carbon Dioxide from the air to make sugars. Humans and animals consume plants, thus acquire the carbon found within the plants. Respiration uses oxygen to breakdown the sugar molecules, thus releasing Carbon Dioxide and H2O Decomposition and Combustion When Bacteria and Fungi decompose organic matter Carbon Dioxide and H2O are released into the environment. Combustion the burning of matter such as wood or fossil fuels. Nitrogen Cycle N is important to living things influences Protein production and making cells for DNA The movement of Nitrogen between the Environment and Living Things is called the Nitrogen Cycle. Nitrogen cycle- Atmospheric nitrogen (N 2 ) makes up nearly 78%-80% of air. Humans and Animals cannot use it in a gas form (that is why plants are important). Without bacteria Nitrogen could not enter living things or be returned Be ed to the Atmosphere. Nitrogen cycle- Only in certain bacteria and industrial technologies can fix nitrogen. Nitrogen fixation-convert atmospheric nitrogen (N 2 ) into ammonium (NH 4 + ) which can be used to make organic compounds like amino acids. N 2 NH 4 + Nitrogen cycle- Nitrogen-fixing bacteria: Some live in symbiotic relationships with plants of the legume family (e.g., soybeans, clover, peanuts). Nitrogen cycle- Some nitrogen-fixing bacteria live free in the soil. Nitrogen-fixing cyanobacteria are essential to maintaining the fertility of semi-aquatic environments like rice paddies. Regrowth Each year millions of acres of land are subjected to heavy lightning and fire. Succession regrowth over a period of time. Primary Succession Over long periods of time where nothing had lived before. Soil is created. Primary Succession Pioneer Species a species that colonizes an uninhabited area and starts the process known as Succession. Creates Soil. Secondary Succession Secondary Succession occurs where communities have already existed such a former farm. May have been destroyed by Natural disasters: floods or Fires Mount Saint Helens 1979 Mount Saint Helens 1980 Sept 2000 Mature Communities They typical have a diverse selection of plants. Mature Communities simply have a wide variety of plants living in the same area not just a Forest. Biodiverse Communities Insects usually attack only one species population at any given time. Diversity provides a chance for many Plants to survive. Toxins in food chains- While energy decreases as it moves up the food chain, toxins increase in potency. This is called biological magnification Ex: DDT & Bald Eagles DDT made their egg shell very thin Breaking Easily. Summary 1 Precipitation, evaporation, transpiration, and condensation are parts of the Water Cycle Summary 1 Photosynthesis, respiration, decomposition, and combustion are parts of the Carbon Cycle. Summary 1 In the Nitrogen Cycle Nitrogen gas is converted into other forms and back again to gas Summary 1 Matter is limited and changes from Environment to Living things and back again. Summary 2 Ecological Succession is the gradual development of communities over time. Often a series of stages is observed during succession. Summary 2 Primary Succession occurs in an area that was not previously inhabited by living things, no soil is present. Succession Summary 2 Secondary Succession takes place in an area where an earlier community was disturbed by Natural Disasters such as landslides, floods, or plowing of the crops and where soil is present.