How Ecosystems Work
Autotrophs vs. Heterotrophs Autotrophs make their own food so they are called PRODUCERS Heterotrophs get their food from another source so they are called CONSUMERS
Two Main forms of Energy for Sunlight The main source of energy for life on earth Photosynthesis Chemical Some organisms such as bacteria, rely on the energy stored in inorganic compounds Chemosynthesis Autotrophs
Types of Consumers Omnivores Herbivores- only eat plants Carnivores - only eat meat Eat plants and meat Detritivores and Decomposers Feeds on plant and animal remains
How does Energy flow through an Ecosystem? Energy flows through an ecosystem in ONE direction, sun or chemicals Autotrophs heterotrophs
Energy Flow in Ecosystems:
Feeding Relationships Food Chain steps of organisms transferring energy by eating & being eaten Food Web network of all the food chains in an ecosystem
Food Web
Ecological Pyramids Trophic Level each step in a food chain or food web Biomass Pyramid Energy Pyramid Pyramid of Numbers
Pyramid of Numbers -relative number of individuals at each trophic level
Pyramid of Biomass - amount of potential food available for each trophic level
Pyramid of Energy - amount of energy available at each trophic level Only 10% of the energy from each trophic level is passed on to the next level Most of the energy is used by the organisms for life processes Some of the energy is lost as heat
How does Matter move through an ecosystem? Unlike the one way flow of energy, matter is recycled within & between ecosystems Nutrients are passed between organisms & the environment through biogeochemical cycles Biogeochemical Cycles: Bio life Geo Earth Chemo chemical 1. WATER CYCLE 2. NUTRIENT CYCLES: a) CARBON CYCLE b) NITROGEN CYCLE c) PHOSPHORUS CYCLE
Why are nutrients important? Every living organism needs nutrients to build tissues and carry out essential life functions. 95% of your body is made of 1) OXYGEN 2) CARBON 3) HYDROGEN 4) NITROGEN
THE WATER CYCLE
Water Water Cycle 1 enters atmosphere by evaporation, transpiration leaves atmosphere as precipitation Water on land filters through ground runs off to lakes, rivers, ocean
Water Cycle 2 Aquifers underground caverns, porous layers of rock store groundwater Runoff movement of surface water from land to ocean
CARBON CYCLE 4 PROCESSES MOVE CARBON THROUGH ITS CYCLE: CO2 1) Biological 2) Geochemical 3) Mixed biochemical 4) Human Activity CO2
Carbon Cycle CO 2 gas enters plants, algae, cyanobacteria photosynthesis turns CO 2 into organic molecules Cellular respiration, combustion, erosion of limestone return CO 2 to water, atmosphere where it is again available to producers
NITROGEN CYCLE Nitrogen-containing nutrients in the biosphere include: 1) Ammonia (NH3) N 2 in Atmosphere 2) Nitrate (NO3-) 3) Nitrite (NO2-) ORGANISMS NEED NITROGEN TO MAKE AMINO ACIDS FOR BUILDING PROTEINS!!! NH 3 N0 3- & N02-
Nitrogen Cycle 1 Nitrogen fixation conversion of nitrogen gas to ammonia Nitrification conversion of ammonia or ammonium to nitrate
Nitrogen Cycle 2 Assimilation conversion of nitrates, ammonia, or ammonium to proteins, chlorophyll, or nitrogen-containing compounds (by plants) conversion of plant proteins into animal proteins
Nitrogen Fixation
PHOSPHORUS CYCLE PHOSPHORUS FORMS PART OF IMPORTANT LIFE-SUSTAINING MOLECULES (ex. DNA & RNA)
Phosphorus Cycle 1 Phosphorus erodes from rock Plants absorb inorganic phosphate from soil (through roots) Animals obtain phosphorus from their diets
Phosphorus Cycle 2 Decomposers release inorganic phosphate into environment Phosphorus washes into ocean is deposited in seabeds lost from biological cycles for millions of years
Succession Succession: Changing Land, Changing Wildlife To an ecologist, the term succession refers to the predictable changes that occur in the plants and animals that live in an area over time. Pioneer species - a species which are first to live on previously uncolonized land. Example: Field - grasses
Succession Primary succession - the series of community changes which occur on an entirely new habitat which has never been colonized before. NO SOIL Example: Lava flow Secondary succession is the series of community changes which take place on a previously colonized, but disturbed or damaged habitat. Examples: pond, fire ecosystems (Pine Barrens)
Primary Succession Example Coastal Sand Dunes
Secondary Succession Example Old Field
Secondary Succession Example NJ Pine Barrens