Nutrient Cycling Biogeochemical Cycles Energy vs Matter Energy
Nutrient Cycling Biogeochemical Cycles
Energy vs. Matter � Energy flows throughout an ecosystem in ONE direction from the sun to autotrophs to heterotrophs � Matter is recycled � WHY?
Biogeochemical Cycles � “Matter can cycle through ecosystems because organisms don’t USE it, they TRANSFORM it. ” � Matter/Nutrient cycled includes: � Water � Nitrogen � Carbon � Phosphorous
Water Cycle �Processes involved: �Evaporation-water changes from liquid to atmospheric gas �Transpiration- water evaporates OUT of plant leaves �Also, condensation, precipitation, runoff…
Carbon Cycle � Key ingredient of living tissue, found in many places � Found in animal skeletons, rocks, carbon dioxide, carbohydrates, etc. � Processes Involved That Take Up and Release Carbon: � Biological- photosynthesis, respiration, decomposition � Geochemical- erosion, volcanic activity � Mixed- burial and decomposition coal and petroleum � Human Activities- mining, cutting and burning forests, burning fossil fuels
Nitrogen Cycle � All organisms require nitrogen to make amino acids � Occurs in many forms: N 2 (78% atm gas), Ammonia (NH 3), Nitrate and Nitrite (NO 3 - and NO 2 -) are found in waste products and fertilizers � Processes involved: � Nitrogen Fixation: conversion of nitrogen gas into ammonia by bacteria (occurs in the roots of legumes) also can occur thru lightning � Ammonia can be converted into nitrates and nitrites, which are taken up by plants and enter the food web � Denitrification: bacteria in soil convert nitrates into nitrogen gas
Phosphorous Cycle � All organisms require phosphorous to create DNA and RNA � Does not enter atmosphere, not very common � Exists inorganic form in land rock and soil minerals and ocean sediment �Processes involved: �Erosion: sediment washes into rivers, streams, and ocean �Absorption: Plants and marine organisms take up the phosphorous and it moves through the food web
- Slides: 13