For example, rock layers show the sequence of geological events, and the presence and amount of radioactive elements in rocks make it possible to determine their ages. Analyses of rock formations and the fossil record are used to establish relative ages.
Soil or water chemistry e. Usually, biological communities include the "functional groupings" shown above. A functional group is a biological category composed of organisms that perform mostly the same kind of function in the system; for example, all the photosynthetic plants or primary producers form a functional group.
Membership in the functional group does not depend very much on who the actual players species happen to be, only on what function they perform in the ecosystem. Processes of Ecosystems This figure with the plants, zebra, lion, and so forth, illustrates the two main ideas about how ecosystems function: These two processes are linked, but they are not quite the same see Figure 1.
Energy flows and material cycles. Energy enters the biological system as light energy, or photons, is transformed into chemical energy in organic molecules by cellular processes including photosynthesis and respiration, and ultimately is converted to heat energy. This energy is dissipated, meaning it is lost to the system as heat; once it is lost it cannot be recycled.
Without the continued input of solar energy, biological systems would quickly shut down. Thus the Earth is an open system with respect to energy. Elements such as carbon, nitrogen, or phosphorus enter living organisms in a variety of ways. Plants obtain elements from the surrounding atmosphere, water, or soils.
Animals may also obtain elements directly from the physical environment, but usually they obtain these mainly as a consequence of consuming other organisms.
These materials are transformed biochemically within the bodies of organisms, but sooner or later, due to excretion or decomposition, they are returned to an inorganic state that is, inorganic material such as carbon, nitrogen, and phosphorus, instead of those elements being bound up in organic matter.
Often bacteria complete this process, through the process called decomposition or mineralization see next lecture on microbes. During decomposition these materials are not destroyed or lost, so the Earth is a closed system with respect to elements with the exception of a meteorite entering the system now and then The elements are cycled endlessly between their biotic and abiotic states within ecosystems.
Those elements whose supply tends to limit biological activity are called nutrients. The Transformation of Energy The transformations of energy in an ecosystem begin first with the input of energy from the sun. Energy from the sun is captured by the process of photosynthesis.
Carbon dioxide is combined with hydrogen derived from the splitting of water molecules to produce carbohydrates the shorthand notation is "CHO". Energy is stored in the high energy bonds of adenosine triphosphate, or ATP see lecture on photosynthesis. The prophet Isaah said "all flesh is grass", earning him the title of first ecologist, because virtually all energy available to organisms originates in plants.
Because it is the first step in the production of energy for living things, it is called primary production click here for a primer on photosynthesis. Herbivores obtain their energy by consuming plants or plant products, carnivores eat herbivores, and detritivores consume the droppings and carcasses of us all.
Figure 2 portrays a simple food chain, in which energy from the sun, captured by plant photosynthesis, flows from trophic level to trophic level via the food chain. A trophic level is composed of organisms that make a living in the same way, that is they are all primary producers plantsprimary consumers herbivores or secondary consumers carnivores.
Dead tissue and waste products are produced at all levels. Scavengers, detritivores, and decomposers collectively account for the use of all such "waste" -- consumers of carcasses and fallen leaves may be other animals, such as crows and beetles, but ultimately it is the microbes that finish the job of decomposition.
Not surprisingly, the amount of primary production varies a great deal from place to place, due to differences in the amount of solar radiation and the availability of nutrients and water.
For reasons that we will explore more fully in subsequent lectures, energy transfer through the food chain is inefficient.News Dive into the world of science! Read these stories and narratives to learn about news items, hot topics, expeditions underway, and much more.
John B Elias Identify a natural ecosystem in which you live or one near to where you live?
How does this ecosystem support you? At what trophic level are you? Why? One of the natural ecosystems where I live in Hudson, New Hampshire, is Ottarnic Pond. SCI Week 2 Ecosystem Paper (New) (2 Papers) Identify a natural ecosystem in which you live or one near to where you live? How does this ecosystem support you?
Create a written plan of no more than words of how you will complete the Natural Resources and Energy Team Paper due in Week Three.
Submit your team’s. Components of an Ecosystem You are already familiar with the parts of an ecosystem. From this course and from general knowledge, you also have a basic understanding of the diversity of plants and animals, and how plants and animals and microbes obtain water, nutrients, and food.
Red Wolf. Canis rufus. Today eastern North Carolina is the only place to find red wolves in the wild. Within their ecosystem, red wolves play a valuable role in keeping prey populations in check.
An aquatic ecosystem is an ecosystem located in a body of water. It comprises aquatic fauna, flora and the properties of water too. There are two types of aquatic ecosystems, Marine and freshwater.