Organization of the Environment © Lisa Michalek

Ecology The study of the interactions between organisms and the living and nonliving components of their environment. An Ecologist is a scientist who studies Ecology.

Ecology Involves Collecting information about organisms and their environment. Looking for patterns. Seeking to explain these patterns.

Environmental Organization In Ecology, organisms and the environment are studied at various ecological levels. Each level includes different factors. Population Community Ecosystem Biosphere

Environmental Organization Population A population includes all the members of a species found in a given area. The dandelion species in your lawn is an example of a population.

Environmental Organization Community A community includes all the populations in a given area. Your lawn has populations of dandelions, grasses, earthworms, and other living things. These populations together make up a lawn community.

Environmental Organization Ecosystem A community (all the living things) and the physical environment (air, water, soil) interacting and functioning together make up an ecosystem. Examples of ecosystems include your lawn, a balanced aquarium, ponds, vacant lots, woodlots, salt marshes, and forests.

Environmental Organization Biosphere The biosphere is the portion of the earth in which life exists. It is very large and includes many complex ecosystems.

Stable Ecosystem Requirements An ecosystem can support itself and is stable when the following requirements are met. There must be a constant supply of energy. The sun is the primary source of energy for life on Earth. There must be living organisms that can incorporate the energy into organic compounds. There must be a recycling of materials between organisms and the environment.

Ecosystem Components Abiotic Factors The nonliving parts of the environment. They directly affect the ability of organisms to live and reproduce. These factors vary from one place to another. Abiotic factors may act as limiting factors. Limiting factors determine the numbers and kinds of organisms that can inhabit an ecosystem.

Abiotic Factors Light Climate (Temperature) Slope of the land Type of Soil Soil chemistry (Minerals) Surface and ground water Air

Ecosystem Components Biotic Factors All the living things that directly or indirectly affect the ecosystem. Biotic factors interact with other living organisms and with the physical environment.

Biotic Factors Producers Any plant that manufactures food by photosynthesis. Green plants are producers. Consumers Consumers eat producers and/or other animals. All animals are consumers. Decomposers Decomposers break down dead organisms and make their materials available to other living things. Bacteria and fungi are examples of decomposers.

Ecosystem Characteristics Abiotic components combine to define the environmental characteristics of the ecosystem. Biotic components interact with each other to determine the success of life in the ecosystem. Biotic components interact with Abiotic components to determine the overall characteristics of the ecosystem.

Habitat The place in the ecosystem where an organism lives. An organism’s habitat is determined by abiotic and biotic factors. The factors an organism needs to survive determine where it lives. Example: An earthworm’s habitat is moist soil.

Niche An organism’s role in the ecosystem. Includes feeding habits, where it lives in the ecosystem, reproductive behavior, and contribution to its surroundings. Example: In a pond, a snail scrapes algae from the leaves and stems of plants.

Biome A geographical area described by its climate, plants, and animals. The temperature and moisture in a biome determines which plants will grow there. Biomes may be terrestrial (land) or aquatic (water) biomes.

Land (terrestrial) Biomes Plant and Animal groups are determined by the major climate zones of the earth. They are sometimes modified by local land and water conditions. The presence or absence of water is a major limiting factor. Climate conditions and communities are affected by latitude (distance north or south of the equator) and altitude (distance above or below sea level).

Terrestrial (Land) Biomes Tundra (polar) Taiga (coniferous forest) Temperate Deciduous Forest Tropical Rain Forest Grassland (savanna) Desert

Tundra (Polar) Permanently frozen subsoil. Animals: Caribou, snowy owl, arctic foxes Plants: Lichens, mosses, grasses Tundra Video

Taiga (Coniferous Forest) Long, severe winters; summers with thawing of subsoil. Animals: Moose, black bear Plants: Coniferous Trees (produce their seeds in cones) spruce, fir, hemlock, cedar, and pine trees Taiga Video

Temperate Deciduous Forest Deciduous Forest Video Moderate precipitation; cold winters, warm summers. Animals: Gray squirrel, fox, deer, raccoons Plants: Trees that shed leaves (deciduous trees), oak, beech, maple, elm trees

Tropical Rain Forest Heavy rainfall; constant warmth. Animals: Snake, monkey, leopard, parrots Plants: Many species of broad-leaved plants, bamboo, ferns Tropical Rain Forest Video

Grassland (Savanna) Rainfall and temperature vary; strong prevailing winds. Animals: Antelope, prairie dog, bison, hawks Plants: Grasses, cereal grains Grassland (Savanna) Video

Desert Little rainfall; extreme daily temperature changes. Animals: Lizard, kangaroo rat, coyotes, camels Plants: Drought-resistant shrubs and plants, cactus Desert Video

Water (aquatic) Biomes Include marine (saltwater) and freshwater biomes. Make up the largest ecosystem on earth. More than 70% of the earth’s surface is covered by water, and more organisms live in water than live on land. Water biomes are typically more stable than land biomes. The temperature varies less because of the ability of water to absorb and hold heat.

Factors Affecting Water Biomes Amounts of available oxygen and carbon dioxide. Temperature and light. Amounts of dissolved minerals and suspended particles.

Aquatic (water) Biomes Marine (saltwater) Freshwater

Marine (saltwater) Oceans, Intertidal Zones Hold large quantities of solar heat Help to stabilize the earth’s atmosphere Contain a constant supply of nutrients and dissolved salts Much of the photosynthesis on earth is carried out by algae near the surface of the oceans and coastal waters. Light penetrates through water to a depth of 30 meters. Photosynthesis does not occur at greater depths.

Freshwater Less than 3% of the Earth’s water is fresh water. Ponds, Swamps, Lakes, Streams, and Rivers will vary by: Size Speed of current Temperature Concentration of dissolved gasses and suspended particles Rate of change