Post on 19-Dec-2015
transcript
Warm-Up #34
Complete analyzing data #1-4 on page 79 of your text
Complete #1-6 Section Assessment on page 80 of your text.
Objectives
Describe how matter cycles among the living and nonliving parts of an ecosystem.
Explain why nutrients are important in living systems.
Describe how the availability of nutrients affects the productivity of ecosystems.
Recycling in the Biosphere
Law of Conservation of Energy and Law of Conservation of Matter—both energy and matter are conserved. Energy --(light→chemical→heat) --needs
a constant input since much is lost to heat throughout the biological processes.
Matter—not a one way path—cycles throughout the ecosystem—same amount is always present in the biosphere—just in different forms.
Biogeochemical Cycles
Connect biological, geological and chemical aspects of the biosphere. Water Carbon Nitrogen Phosphorus
Biogeochemical Cycles
In studying cycling of water, carbon, nitrogen, and phosphorus, ecologists focus on four factors:1. Each chemical’s biological importance2. Forms in which each chemical is
available or used by organisms3. Major reservoirs for each chemical4. Key processes driving movement of
each chemical through its cycle
The Water CycleEvaporation
Transpiration
Condensation
Precipitation
One H2O molecule may
take as long as 4000 years to
complete 1 cycle.
The Water Cycle
• Biological Importance: All living things require water to survive.
• Forms available: Water Vapor, Liquid Water and Ice
• Major Reservoirs: Oceans, Lakes, Rivers, Atmosphere
• Key Processes Driving Movement: – Evaporation (Transpiration)– Condensation (clouds)– Precipitation (rain, snow, etc)– Runoff
Nutrient Cycles
All the chemical substances that an organism needs to sustain life.
Every living organism needs nutrients to build tissues and carry out essential life functions.
Like water, nutrients are passed between organisms and the environment through biogeochemical cycles.
The Carbon Cycle ONLY photosynthesis removes Carbon from the atmosphere.
Other processes key to this cycle:
Respiration
Decomposition
The Carbon Cycle
• Biological Importance—Carbon forms the framework for the organic molecules essential to all organisms.
• Forms Available—Carbon Dioxide, Calcium Carbonate, Coal, Oil, Gas
• Major Reservoirs—CO2 in atmosphere, CaCO3 in the ocean
• Key Processes—photosynthesis, respiration, burning of fossil fuels, weathering, erosion, decay, volcanism
The Nitrogen Cycle The atmosphere is about 80% nitrogen. Mainly bacteria make this nitrogen available to the rest of the living world by chemically treating it and making it available to plants.
The Nitrogen Cycle
• Biological Importance: – Nitrogen is a component of amino acids, proteins, and
nucleic acids and is a crucial and often limiting plant nutrient
• Forms Available: – Ammonia, Nitrates, Atmospheric Nitrogen
• Major Reservoirs: – Atmosphere, Soil
• Key Processes: – Nitrification, Denitrification, Ammonification, Nitrogen
Fixation, Decomposition, Lightning Storms
The Phosphorus Cycle Very localized cycle with no atmospheric component.
Like the nitrogen and carbon cycles phosphorus is take into the food chain through plants.
The Phosphorus Cycle
Biological Importance: Organisms require phosphorus as a major component in nucleic acids, phospholipids, ATP, and as a mineral constituent of bones and teeth
Forms available: Inorganic phosphate
Major Reservoirs: Rock and soil minerals, ocean sediments
Key Processes: Erosion, Runoff, Mineral absorption by plant roots
Nutrient Limitation
Primary Productivity—the rate at which organic matter is created by producers.
Limiting Nutrient—a single nutrient whose availability will limit the primary productivity of an ecosystem.
Land ecosystems are much more nutrient rich than the oceans. In oceans, phosphorus is generally the limiting nutrient.
Algal Bloom
When an aquatic ecosystem receives a large input of a limiting nutrient—such as large amounts of phosphorus from fertilizer runoff—the result is often an immediate increase in the amount of algae and other producers.
This increase of algae is known as algal bloom.
Large blooms can sometimes disrupt the equilibrium of an ecosystem.
Summary
How does matter cycle among the living and nonliving parts of an ecosystem?
How is this different than the flow of energy?
Why are nutrients important in living systems?
Water? Carbon? Nitrogen? Phosophorus? How does the availability of nutrients
affect the productivity of ecosystems?