logging in or signing up Ecologypost Perrin Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 870 Category: Education License: All Rights Reserved Like it (2) Dislike it (0) Added: February 05, 2008 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... By: shemmie (10 month(s) ago) I am a student and i need this presentation... plz sent this ppt as soon as possible Saving..... Post Reply Close Saving..... Edit Comment Close By: jothimanojkumar (23 month(s) ago) i am a lecturer and ur ppt is very good. pls send this ppt. Saving..... Post Reply Close Saving..... Edit Comment Close By: AEBurruss (43 month(s) ago) Can I borrow some of your PPT? Annburruss@yahoo.com Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Slide1: Ecosystems Energy and Nutrient CyclingOutline: Outline I. Ecosystems A. Definition B. Energy Flow within Ecosystems 1. Trophic Relationships 2. Energy Budgets 3. Ecological Pyramids C. Nutrient Cycling 1. Biogeochemical Cycles 2. Nutrient Pollution Ecosystem: Ecosystem All of the organisms living in a particular place as well as the chemical/physical factors with which they interact. Range in size from small (like aquarium) to large (like forest) E.g. desert ecosystem: organisms that live there (cacti, snakes, rodents), soil chemistry, average rainfall, temperatures etc.Energy Flow: Energy Flow Energy flows through ecosystems, while matter cycles within them Resources critical to human survival and welfare, ranging from the food we eat to the oxygen we breathe, are products of ecosystem processes Energy Flow: Energy Flow Energy in ecosystems follows the rules of thermodynamics Ecosystems are open systems where energy (generally from the sun) is input, is transformed, and is ultimately released as heat from organisms Heat lost from organisms is disordered, unusable energy and therefore has increased entropy of the system Energy transfers between organisms are not completely efficient Without energy input (sun) ecosystems collapseTrophic Relationships: Trophic Relationships Trophic level: how an organism gets it’s nutrition (energy) All organisms at a particular trophic level are the same number of transfer steps away from the energy input into the system Food Web: who eats whom in the ecosystem Interconnected food chains Energy flows through ecosystems via trophic levels within the food web Trophic Levels: Trophic Levels Primary producers: 1st trophic level-the autotrophs-capture sun energy (the initial energy source for almost all of earth’s ecosystems) Primary consumers: heterotrophs-herbivores (caterpillars, cows etc), feed on primary producers Secondary consumers: carnivores (birds, wolves etc), feed on primary consumers Tertiary consumers: carnivores that feed on other carnivoresDecomposers: Decomposers aka detritivores -consumers that get their energy from detritus-nonliving organic material Dead organisms, feces, leaf litter, wood Bacteria, fungi, animals which feed on detritus like earthworms Decompose organic material in ecosystem and transfer chemical elements in inorganic forms to reservoirs such as soil, water, and air Decomposition by bacteria and fungi accounts for most conversion of organic materials from all trophic levels to inorganic compounds usable by primary producers (thereby closing the loop of nutrient cycling) Ecosystem Energy Budgets: Ecosystem Energy Budgets Primary production: amount of light energy converted to chemical energy by autotrophs in a given time period. Sets the “spending limit” for the energy budget of the ecosystem Of the visible light that reaches the earth, only about 1% is converted to chemical energy by photosynthesis Biomass: amount of biological material in a group of organisms in an ecosystem (ex. weight of all trees)Ecological Pyramids: Ecological Pyramids A good portion of the energy produced by primary producers is used to fuel their life functions-cellular respiration, growth, reproduction-this is true at every trophic level General rule: only about 10% of the energy contained in a particular trophic level is available for transfer to the next trophic levelEcological Pyramids: Ecological Pyramids The only generalization in an ecosystem that always holds true: energy decreases with each successive trophic level Some generalizations that are often true: # of individuals decreases as you increase trophic level Size of individuals increases as you increase trophic level Nutrient Cycling in Ecosystems: Nutrient Cycling in Ecosystems Within an ecosystem nutrients are cycled internally, there are leaks (outputs) like erosion and timber/crop harvest Must be replaced by nutrient inputs: Weathering of rocks Windblown dust Precipitation Decomposition into form available to plants Nutrient Cycling in Ecosystems: Nutrient Cycling in Ecosystems Nutrients are carried from terrestrial ecosystems by movement of water and deposited in aquatic ecosystems and associated lowlands If inputs exceed outputs, the nutrient cycle in the ecosystem becomes stressed or overloaded resulting in pollution (nutrient levels exceed capability of the ecosystem to process them)Nutrient Cycling in Ecosystems: Nutrient Cycling in Ecosystems Nutrients eroded from agricultural lands, sewage, industrial wastes drain into streams, rivers, lakes and estuaries These pollutants destroy plants and animals that cannot tolerate their presence or the changed environmental conditions caused by them You do not have the permission to view this presentation. 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Ecologypost Perrin Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 870 Category: Education License: All Rights Reserved Like it (2) Dislike it (0) Added: February 05, 2008 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... By: shemmie (10 month(s) ago) I am a student and i need this presentation... plz sent this ppt as soon as possible Saving..... Post Reply Close Saving..... Edit Comment Close By: jothimanojkumar (23 month(s) ago) i am a lecturer and ur ppt is very good. pls send this ppt. Saving..... Post Reply Close Saving..... Edit Comment Close By: AEBurruss (43 month(s) ago) Can I borrow some of your PPT? Annburruss@yahoo.com Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Slide1: Ecosystems Energy and Nutrient CyclingOutline: Outline I. Ecosystems A. Definition B. Energy Flow within Ecosystems 1. Trophic Relationships 2. Energy Budgets 3. Ecological Pyramids C. Nutrient Cycling 1. Biogeochemical Cycles 2. Nutrient Pollution Ecosystem: Ecosystem All of the organisms living in a particular place as well as the chemical/physical factors with which they interact. Range in size from small (like aquarium) to large (like forest) E.g. desert ecosystem: organisms that live there (cacti, snakes, rodents), soil chemistry, average rainfall, temperatures etc.Energy Flow: Energy Flow Energy flows through ecosystems, while matter cycles within them Resources critical to human survival and welfare, ranging from the food we eat to the oxygen we breathe, are products of ecosystem processes Energy Flow: Energy Flow Energy in ecosystems follows the rules of thermodynamics Ecosystems are open systems where energy (generally from the sun) is input, is transformed, and is ultimately released as heat from organisms Heat lost from organisms is disordered, unusable energy and therefore has increased entropy of the system Energy transfers between organisms are not completely efficient Without energy input (sun) ecosystems collapseTrophic Relationships: Trophic Relationships Trophic level: how an organism gets it’s nutrition (energy) All organisms at a particular trophic level are the same number of transfer steps away from the energy input into the system Food Web: who eats whom in the ecosystem Interconnected food chains Energy flows through ecosystems via trophic levels within the food web Trophic Levels: Trophic Levels Primary producers: 1st trophic level-the autotrophs-capture sun energy (the initial energy source for almost all of earth’s ecosystems) Primary consumers: heterotrophs-herbivores (caterpillars, cows etc), feed on primary producers Secondary consumers: carnivores (birds, wolves etc), feed on primary consumers Tertiary consumers: carnivores that feed on other carnivoresDecomposers: Decomposers aka detritivores -consumers that get their energy from detritus-nonliving organic material Dead organisms, feces, leaf litter, wood Bacteria, fungi, animals which feed on detritus like earthworms Decompose organic material in ecosystem and transfer chemical elements in inorganic forms to reservoirs such as soil, water, and air Decomposition by bacteria and fungi accounts for most conversion of organic materials from all trophic levels to inorganic compounds usable by primary producers (thereby closing the loop of nutrient cycling) Ecosystem Energy Budgets: Ecosystem Energy Budgets Primary production: amount of light energy converted to chemical energy by autotrophs in a given time period. Sets the “spending limit” for the energy budget of the ecosystem Of the visible light that reaches the earth, only about 1% is converted to chemical energy by photosynthesis Biomass: amount of biological material in a group of organisms in an ecosystem (ex. weight of all trees)Ecological Pyramids: Ecological Pyramids A good portion of the energy produced by primary producers is used to fuel their life functions-cellular respiration, growth, reproduction-this is true at every trophic level General rule: only about 10% of the energy contained in a particular trophic level is available for transfer to the next trophic levelEcological Pyramids: Ecological Pyramids The only generalization in an ecosystem that always holds true: energy decreases with each successive trophic level Some generalizations that are often true: # of individuals decreases as you increase trophic level Size of individuals increases as you increase trophic level Nutrient Cycling in Ecosystems: Nutrient Cycling in Ecosystems Within an ecosystem nutrients are cycled internally, there are leaks (outputs) like erosion and timber/crop harvest Must be replaced by nutrient inputs: Weathering of rocks Windblown dust Precipitation Decomposition into form available to plants Nutrient Cycling in Ecosystems: Nutrient Cycling in Ecosystems Nutrients are carried from terrestrial ecosystems by movement of water and deposited in aquatic ecosystems and associated lowlands If inputs exceed outputs, the nutrient cycle in the ecosystem becomes stressed or overloaded resulting in pollution (nutrient levels exceed capability of the ecosystem to process them)Nutrient Cycling in Ecosystems: Nutrient Cycling in Ecosystems Nutrients eroded from agricultural lands, sewage, industrial wastes drain into streams, rivers, lakes and estuaries These pollutants destroy plants and animals that cannot tolerate their presence or the changed environmental conditions caused by them