ecosystems. questions for today: what are the major components of an ecosystem? how do abiotic...
TRANSCRIPT
Ecosystems
Questions for Today:
• What are the major components of an Ecosystem?
• How do abiotic factors affect Ecosystems?
• How do biotic factors affect Ecosystems?
• Describe the Energy flow and nutrient cycling in Ecosystems.
Ecosystems have Living and Nonliving Components
• An Ecosystem is a community of different species interacting with one another and with their nonliving environment of matter and energy.
• Two components:– Abiotic – nonliving components– Biotic – Living components
Ecosystems have Living and Nonliving Components• Each population in an ecosystem has a
range of tolerance to variations in its physical and chemical environments.
How do Abiotic Factors affect Ecosystems?
• Abiotic Factors affect Ecosystem through limiting factors.– Limiting factors are any abiotic factor that
affects the number of organisms in a population.
• Limiting Factor Principle states:“Too much or too little of any abiotic factor can limit
or prevent growth of a population, even if all other factors are at or near the optimal range of
toletance.”
Limiting Factors
• On land, the major limiting factors are:– Precipitation– Soil Nutrients– Temperature
• In aquatic life zones, the major limiting factors are:– Temperature– Nutrient Availability– Sunlight– Dissolved Oxygen– Salinity– pH
Living Components of an Ecosystem
• All living organisms are assigned a trophic level or feeding level.
• The first trophic level are the producers.
• Producers are autotrophs that make their own food through the use of photosynthesis or chemosynthesis
• On land, producers are usually green land plants that capture 1% of the sun’s energy.
Living Components of Ecosystems
• In aquatic lifezones, the major producers are algae and phytoplankton.
• Photosynthesis uses light to make glucose
• Chemosynthesis may use inorganic compounds to create organic compounds.– Found near hydrothermal vents.
Living Components of Ecosystems
• Consumers eat producers and other consumers.• Consumers are heterotrophs• Several types of consumers:
– Primary Consumers (Herbivores)– Secondary Consumers (Carnivores)– Tertiary and Higher Consumers (Large Carnivores)– Omnivores– Decomposers– Detritus Feeders
Living Components of Ecosystems
• In order to obtain the energy from the sun, consumers breakdown the bonds in organic compounds using cellular respiration.
• Two types:– Aerobic and anaerobic.
• All organisms, plant and animal, carry out respiration. Only plants carry out photosynthesis.
Energy Flow and Nutrient Cycling
• Ecosystems are sustained through a combination of one-way energy flow, nutrient cycling.
• Decomposers and Detritus Feeders are essential in environments because they can cycle nutrients back into the soil and help producers to grow.