If you consider all regions on earth where living organisms are found, this would be considered the

Beerling, D. The Emerald Planet: How Plants Changed Earth's History. Oxford, UK: Oxford University Press, 2007.

Biro, P. A., Beckmann, C. et al. Small within-day increases in temperature affects boldness and alters personality in coral reef fish. Proceedings of the Royal Society B: Biological Sciences 277, 71-77 (2010).

Burger, W. C. Flowers: How They Changed the World. Amherst, NY: Prometheus Books, 2006.

Chapin, F. S., Matson, P. A. et al. Principles of Terrestrial Ecosystem Ecology. New York, NY: Springer Science+Business Media Inc., 2002.

Chapin, F. S., Vitousek, P. M. et al. The nature of nutrient limitation in plant communities. The American Naturalist 127, 48 (1986).

Cowen, R. History of Life. Boston, MA: Blackwell Scientific Publications, 1990.

Dethlefsen, L., Huse, S. et al. The pervasive effects of an antibiotic on the human gut microbiota, as revealed by deep 16S rRNA sequencing. PLoS Biology 6, e280 (2008).

Gaston, K. J. Global patterns in biodiversity. Nature 405, 220-227 (2000).

Hata, H., Watanabe, K. et al. Geographic variation in the damselfish-red alga cultivation mutualism in the Indo-West Pacific. BMC Evolutionary Biology 10, 185 (2010).

Kleidon, A., Fraedrich, K. et al. A green planet versus a desert world: estimating the maximum effect of vegetation on the land surface climage. Climatic Change 44, 471-493 (2000).

Marquez, L. M., Redman, R. S. et al. A virus in a fungus in a plant: three-way symbiosis required for thermal tolerance. Science 315, 513-515 (2007).

May, R. M. How many species are there on Earth? Science 241, 1441-1449 (1988).

Morton, O. Eating the Sun: How Plants Power the Planet. New York, NY: HarperCollins, 2008.

Parker, A. R. & Lawrence, C. R. Water capture by a desert beetle. Nature 414, 33-34 (2001).

Pringle, R. M., Doak, D. F. et al. Spatial pattern enhances ecosystem functioning in an African savanna. PLoS Biol 8, e1000377 (2010).

Riedman, M. Sea Otters. Monterey, CA: Monterey Bay Aquarium Press, 1990.

Riedman, M. The Pinnipeds: Seals, Sea Lions, and Walruses. Berkeley, CA: University of California Press, 1991.

Schlesinger, W. H. An analysis of global change. In Biogeochemistry. 2nd ed. (New York: Academic Press, 1997).

World Health Organization. Millennium Ecosystem Assessment: Ecosystems and Human Well-being: General Synthesis. Washington, DC: Island Press, 2005.

The biosphere is the area of Earth where living things exist. The biosphere is divided into regions known as biomes. In general, biomes are areas with a particular type of climate and similar plant and animal species. Biomes can be further subdivided into dynamic, interrelated systems of plants and animals, nonliving matter, and the energy of the system. These are called ecosystems. Ecosystems vary in size. They can be as small as a puddle or as large as Earth itself. Any group of living and nonliving things interacting with each other can be considered as an ecosystem.

Within each ecosystem, there are habitats which may also vary in size. A habitat is a place where plants and animals normally live. Some habitats have lots of plants and animals, some do not. Some habitats are near water, some are on top of mountains. Each habitat has a different mixture of species living there. A habitat is the place where a population lives. A population is a group of living organisms of the same kind living in the same place at the same time. All of the plant and animal populations living in a habitat interact and form a community.

The community of living (biotic) things interacts with the nonliving (abiotic) world around it to form the ecosystem. The habitat must supply the needs of organisms, such as food, water, air, and space to grow. If the population’s needs are not met, it will move to a better habitat or die.

No organism on Earth is an isolated individual. Every form of life is part of an ecosystem. In reality, the entire planet is one ecosystem. The study of ecosystems is a branch of biology known as ecology.

A change and/or interruption of an interrelationship in an ecosystem can cause large-scale changes in the ecosystem. Human actions or their results are often the cause of these changes. (Source: South Brunswick Public Schools, Science Curriculum: Eat or Be Eaten, NJ, 2008.)

What does ecology have to do with me?

Ecology is the study of the relationships between living organisms, including humans, and their physical environment; it seeks to understand the vital connections between plants and animals and the world around them. Ecology also provides information about the benefits of ecosystems and how we can use Earth’s resources in ways that leave the environment healthy for future generations.

Who are Ecologists?

Ecologists study these relationships among organisms and habitats of many different sizes, ranging from the study of microscopic bacteria growing in a fish tank, to the complex interactions between the thousands of plant, animal, and other communities found in a desert.

Ecologists also study many kinds of environments. For example, ecologists may study microbes living in the soil under your feet or animals and plants in a rain forest or the ocean.

The Role of Ecology in Our Lives

The many specialties within ecology, such as marine, vegetation, and statistical ecology, provide us with information to better understand the world around us. This information also can help us improve our environment, manage our natural resources, and protect human health. The following examples illustrate just a few of the ways that ecological knowledge has positively influenced our lives.

Improving Our Environment

Pollution from Laundry Detergents & Fertilizers
In the 1960s, ecological research identified two of the major causes of poor water quality in lakes and streams-phosphorous and nitrogen-which were found in large amounts in laundry detergents and fertilizers. Provided with this information, citizens were able to take the necessary steps to help restore their communities’ lakes and streams-many of which are once again popular for fishing and swimming.

Non-Native or Introduced Species Invasions

An image of Kudzu covered trees in Atlanta Georgia, USA

Some non-native species (plants, animals, microbes, and fungi not originally from a given area) threaten our forests, croplands, lakes, and other ecosystems. Introduced species, such as the kudzu vine shown here, do this by competing with plants and animals that were originally there, often damaging the environment in the process. For example, the gypsy moth, a native of Europe and Asia, wreaks havoc on great swaths of forest lands by defoliating, or eating the leaves off of trees. At first, highly toxic chemicals, which also poisoned other animals, were the only methods available to control this introduced pest. By targeting vulnerable stages in the moths’ life cycle, ecologists devised less toxic approaches to control their numbers.

Public Health

Natural Services

Wetland clean up site at Ft. McHenry, Baltimore.

Ecologists have discovered that marshes and wetlands filter toxins and other impurities from water. Communities can reap the benefit of this ecological service. Leaving some of these filtering ecosystems intact can reduce the burden on water treatment plants that have been built to perform the same service. By using natural filtering systems, we have the option to build fewer new treatment plants.

Biomedical Contributions

Ecologists have discovered that many plants and animals produce chemicals that protect them from predators and diseases. Some of these same chemicals have been synthesized by scientists or harvested from the organism and used to treat human diseases. For example, the Pacific Yew tree produces a substance which is used in cancer treatments. Another example is a substance found in horseshoe crabs, hemolymph, that is used in leukemia treatments.

Lyme Disease

An adult deer tick (Ixodes scapularis) sits on a leaf. USDA photo by Scott Bauer.

Lyme Disease is a potentially serious bacterial infection that is transmitted to humans by certain ticks. Ecological studies have found that people are more likely to get Lyme disease when acorns are plentiful. Why? Because mice and deer, which carry the disease and the ticks, feed on acorns. More acorns usually mean more mice and deer, providing a favorable environment for large populations of ticks to flourish. Knowing the connections between acorns, deer, mice, and ticks, ecologists are able to predict the likelihood of infection and let people know when they need to be more careful when outdoors.

Natural Resource Management

Endangered Species Protection

Some of our nation’s most cherished species, such as the bald eagle and peregrine falcon, as well as countless other less familiar species, like the Virginia Big-Eared Bat and the American Burying Beetle, have either been brought back from the brink of extinction or their populations have been stabilized. These successes are the result of successful captive breeding efforts, reintroduction methods, and a greater understanding of species, in part because of ecological research.

Forestry Solutions

Graduate student Christina Bielski recorded data during a high intensity prescribed fire burning through juniper-invaded grassland on private property. Credit, Dirac Twidwell.

Ecological concepts have been applied to forest management and are slowly being integrated into traditional forest science. For example, ecological studies have shown that fire plays a key role in maintaining healthy forest ecosystems in certain types of forests. This knowledge has encouraged more research to find ways to use controlled fires to prevent unpredictable and costly wildfires.

Agricultural Solutions

Glyphosate fields

Biological control is a technique that uses the natural enemies and predators of pests to control damage to crops. It is based in part on knowing the ecology of pests, which is used to understand when and where they are the most vulnerable to their enemies. Biological control alleviates crop damage by insects, saves money, and decreases problem associated with pesticides.

Fishing Solutions

A fishing vessel trawls. Photo courtesy: Joachim Müllerchen

Ecological research has shown that estuaries are nursery grounds for fish populations that live in coastal waters, an important reason to protect these areas. Ecological research has also identified obstacles, such as dams, that fish encounter when returning to their breeding areas. This information has been used to help design structures for fish so they can move around these obstacles to reach their breeding areas.

Common Terms

Ecosystem

Broadleaf trees and tamarack burn gold with fall color against the ever-green of conifers in the northeast corner of Denali National Park & Preserve. The low (relative to the core of the Alaska Range, which includes Denali, the highest mountain in North America) Teklanika Hills loom in the background. In the foreground, the Teklanika River flows northeastward into the Tanana River drainage, a major tributary of the mighty Yukon River. Credit, Tim Rains, Denali National Park and Preserve, 2011.

An ecosystem is any geographic area that includes all of the organisms and nonliving parts of their physical environment. An ecosystem can be a natural wilderness area, a suburban lake or forest, or a heavily used area such as a city. The more natural an ecosystem is, the more ecosystem services it provides. These include cleansing the water (wetlands and marshes) and air (forests), pollinating crops and other important plants (insects, birds, bats), and absorbing and detoxifying pollutants (soils and plants).

Biodiversity

Short for biological diversity, biodiversity is the range of variation found among microorganisms, plants, fungi, and animals. Some of this variation is found within species, such as differences in shapes and colors of the flowers of a single species of plants. Biodiversity also includes the richness of species of living organisms on earth.

Environment

Overhead view of the 2010 BP oil spill from the ocean drilling rig, Deepwater Horizon

The environment is the surroundings of an organism including the physical and chemical environment, and other organisms with which it comes into contact. This term is most frequently used in a human context, often referring to factors affecting our quality of life.

Natural Resources

The Dabob Bay Natural Area was established in 1984 to protect rare examples of intact salt marsh and sand spit plant communities within one of Washington State’s highest functioning coastal spit and tidal wetland systems. Credit, Washington Department of Natural Resources.

Natural resources are living and nonliving materials in the environment that are used by humans. There are two types: renewable (wildlife, fish, timber, water) and nonrenewable (fossil fuels and minerals).

Population

A group of seals lay atop a rock.

A group of individuals belonging to one species (of bacteria, fungi, plant, or animal) living in an area.

Community

Populations of organisms of different species that interact with one another.

Where Can I Go For More Information or Assistance?

If you are interested in learning more about ecology, or would like to know what you can do to become involved, a number of resources are at your disposal. Public and university libraries offer articles, journals, and books on a range of ecological research.

Many environmental organizations have developed educational materials that focus on species and ecosystems, and offer tips on becoming involved in community activities that relate to the environment. Finally, professional ecological organizations can connect you with scientific experts in all types of ecological study, from those that specialize in wetland ecology, to those that focus on endangered species, to those whose work emphasizes city environments.

Issues in Ecology

Issues in Ecology #21. Fall 2019

This series of reports providing key scientific information on current environmental issues is published by the Ecological Society of America with support from the Pew Foundation and from the Environmental Protection Agency, Office of Sustainable Ecosystems and Communities.

For a current list of Issues in Ecology, please visit:

https://www.esa.org/publications/issues/

Benefits of Ecological Research

Ecological Research Benefits one-pager, Case Study 1: The Hantavirus
Ecological Benefits one-pager, Case Study 2: Lyme Disease

What is all regions of Earth where organisms live?

The biosphere is made up of the parts of Earth where life exists—all ecosystems. The biosphere extends from the deepest root systems of trees, to the dark environments of ocean trenches, to lush rain forests, high mountaintops, and transition zones like this one, where ocean and terrestrial ecosystems meet.

What is the term for all living things on the Earth?

Encyclopedic Entry Vocabulary. Biodiversity is a term used to describe the enormous variety of life on Earth. It can be used more specifically to refer to all of the species in one region or ecosystem. Biodiversity refers to every living thing, including plants, bacteria, animals, and humans.

What determines the type of organisms living in a region?

A biome is an area classified according to the species that live in that location. Temperature range, soil type, and the amount of light and water are unique to a particular place and form the niches for specific species allowing scientists to define the biome. However, scientists disagree on how many biomes exist.

What are regions where organisms actively interact with each other and the environment called?

Ecosystems. The living organisms on Earth live and interact in different ecosystems around the planet. Together all these ecosystems make up the Earth's biosphere. An ecosystem consists of the abiotic (non-living) environment and the biotic (living) organisms.