Biology Ecology Ch. 42 Ecosystem

Gross primary production

The total primary production of an ecosystem

Precipitation

the action or process of precipitating a substance from a solution (rain, snow, sleet, or hail that falls to the ground)

Primary production

the amount of chemical energy that autotrophs produce from light energy during a given period of time. Biomass is the dry weight of organic matter produced by primary productivity.

Nitrification

the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate.

Nitrogen fixation

the chemical processes by which atmospheric nitrogen is assimilated into organic compounds, especially by certain microorganisms as part of the nitrogen cycle

Condensation

the conversion of a vapor or gas to a liquid

Denitrification

the loss or removal of nitrogen or nitrogen compounds; specifically : reduction of nitrates or nitrites commonly by bacteria (as in soil) that usually results in the escape of nitrogen into the air

Assimilation

the process through which an organism incorporates nutrients from outside its body to the more complex structures needed inside of it

Know the laws of thermodynamics and matter

1. Law of Conservation of Energy: energy cannot be created or destroyed in an isolated system. 2. the entropy of any isolated system always increases. 3. the entropy of a system approaches a constant value as the temperature approaches absolute zero.

Detritivores

A decomposer-A consumer that derives its energy and nutrients from nonliving organic material such as corpses, fallen plant material, and the wastes or living organisms

Eutrophication

A process, by which nutrients, particularly Phosphorous and nitrogen, become highly concentrated in a body of water, leading to increased growth of organisms such as algae or cyanobacteria

Adaptations for plants to acquire limiting nutrients

All plants respond in a qualitatively similar way to low availability of major nutrients by reduced acquisition, lower tissue nutrient concentrations (high efficiency of nutrient use), reduced growth, and effective retranslocation of nutrients from senescing leaves. Such plants maximize their efficiency of nutrient use primarily by prolonging tissue life so that each unit of nutrient provides a maximum return before being lost from the plant.

Ecosystem

All the organisms in a given area as well as the abiotic factors with which they interact (one or more communities and the physical environment around them)

Limiting nutrients

An element that must be added for production to increase in a particular area

Biogeochemical cycles

Any of the various chemical cycles that involve both biotic and abiotic components of the ecosystems

Roles of decomposers in ecosystems and matter cycling

At the end of the food chain, decomposers act as the "clean-up crew" -- they consume dead animal carcasses, decaying plant material and waste products from other members of the ecosystem. Earthworms, for example, take in soil and microorganisms and excrete waste filled with nutrients, which are added to the soil. Fungi absorb nutrients from the plants and animals they consume while releasing enzymes that break down dead organic matter.

Analyze trophic structure and food webs

Autotrophs, the primary producers of the ecosystem, ultimately support all other organisms. Most autotrophs are photosynthetic plants, algae or bacteria that use light energy to synthesize sugars and other organic compounds. Chemosynthetic prokaryotes are the primary producers in deep-sea hydrothermal vents. Heterotrophs are at trophic levels above the primary producers and depend on their photosynthetic output. Herbivores that eat primary producers are called primary consumers. Carnivores that eat herbivores are called secondary consumers. Carnivores that eat secondary producers are called tertiary consumers. Another important group of heterotrophs is the detritivores, or decomposers. They get energy from detritus, nonliving organic material such as the remains of dead organisms, feces, fallen leaves, and wood. Detritivores play an important role in material cycling.

Detritus

Dead organic matter

How much energy is transferred from one trophic level to the next in an ecosystem?

Energy transfer between trophic levels is usually less than 20% (about 10%)

Production limitations in marine environments and terrestrial environments

In aquatic ecosystems, light and nutrients limit primary production. In terrestrial ecosystems, temperature and moisture are the key factors limiting primary production.

What are the typical limiting nutrients for marine and terrestrial ecosystems?

In aquatic ecosystems, light and nutrients limit primary production. In terrestrial ecosystems, temperature and moisture are the key factors limiting primary production.

Primary producers

Make up the trophic level of an ecosystem that ultimately supports all other levels (autotrophs)

Nitrogen cycle

Nitrogen enters ecosystems primarily through bacterial nitrogen fixation. Some nitrogen is fixed by lightning and industrial fertilizer production. Ammonification by bacteria decomposes organic nitrogen. In nitrification, bacteria convert NH4+ to NO3?. In denitrification, bacteria use NO3? for metabolism instead of O2, releasing N2.

Carbon cycle

Photosynthesis by plants and phytoplankton fixes atmospheric CO2. CO2 is added to the atmosphere by cellular respiration of producers and consumers. Volcanoes and the burning of fossil fuels add CO2 to the atmosphere.

Autotrophs

Primary producers

Net primary production

The GPP minus the energy used by the producers for respiration. This is the only available energy for the next trophic level

Trophic efficiency

The Percentage of production transferred from one trophic level to the next

Secondary production

The amount of chemical energy in consumer's food that is converted to their own new biomass

Water cycle

The main processes driving the water cycle are evaporation of liquid water by solar energy, condensation of water vapor into clouds, and precipitation. Transpiration by terrestrial plants moves significant amounts of water. Surface and groundwater flow returns water to the oceans.

Production efficiency

The percentage of energy stored in assimilated food that is not used for respiration or eliminated as waste

Evaporation

The process of a substance in a liquid state changing to a gaseous state due to an increase in temperature and/or pressure

Transpiration

The process when a plant absorbs water in its roots

Effect of location on primary production between different ecosystems

Total primary production in an ecosystem is known as gross primary production (GPP). This is the amount of light energy that is converted into chemical energy per unit time. Overall, terrestrial ecosystems contribute two-thirds of global net primary production, and marine ecosystems contribute approximately one-third. In aquatic ecosystems, light and nutrients limit primary production. Light is a key variable controlling primary production in oceans, since solar radiation can only penetrate to a certain depth known as the photic zone.

Phosphorus cycle

Weathering of rocks gradually adds phosphate to soil. Some phosphate leaches into groundwater and surface water and moves to the sea. Phosphate may be taken up by producers and incorporated into organic material. It is returned to soil or water through decomposition of biomass or excretion by consumers.

Heterotrophs

consumers or organisms

Ammonification

decomposition with production of ammonia or ammonium compounds especially by the action of bacteria on nitrogenous organic matter

The difference between movement of energy and matter through ecosystems

matter is recycled within and between ecosystems. Energy flow is a one-way flow