04: The Ecosystem Flashcards
This can be defined as an ecological unit consisting of a biotic community (an assemblage of plant, animal, and other living organisms) together with its abiotic environment (such as soil, precipitation, sunlight, temperature, slope of the land, etc.).
An ecosystem (or Ecosystem)
The word ecosystem is an abbreviation of the term, “____.” A river, a swamp, a meadow, and a cave are all examples of ecosystems. Some consider the ____ to be the basic unit in ecology.
Ecological System, Ecosystem
Kinds of Ecosystem
Riverine ecosystem
Lacustrine ecosystem
Marine ecosystem
Boundary ecosystem (where one body of water meets another (estuaries and lagoons); where a body of water meets land (wetlands); where one land area meets another land type)
Soil ecosystem
Polar ecosystem (in polar regions, such as polar barrens and tundra)
Mountain ecosystem
Agroecosystem (farms, livestock production systems)
Forest ecosystem
Grassland ecosystem
Urban ecosystem (cities, suburbs)
Kind of Riverine Ecosystem
• River ecosystem
• Stream ecosystem
• Spring ecosystem
Kind of Lacustrine Ecosystem
• Pond ecosystem
• Lake ecosystem
Kind of Marine Ecosystem
• Coastal water ecosystem
° Estuary ecosystem
° Lagoon ecosystem
• Coral reef ecosystem
• Soft-bottom continental shelf ecosystem
• Upwelling continental shelf ecosystem
• Open ocean ecosystem
• Polar ocean ecosystem (the Arctic and Antarctic oceans)
A major process linking the abiotic and biotic constituents of ecosystems is the flow of energy.
Energy Flow
The main source of energy in almost all natural ecosystems is ____ from the ___.
Radiant Energy, Sun
These organisms, such as plants, algae, and photosynthetic bacteria, take radiant energy and fix it into organic molecules by photosynthesis, such a creating glucose from carbon dioxide.
Primary Producers or Autotrophic Organisms
Another process is Chemosynthesis
These organisms utilize the energy fixed in organic molecules by autotrophs.
Heterotrophs
These organisms are heterotrophs that eat autotrophs, such as antelopes that feed on grass or zooplankton that feed on phytoplankton in the ocean or in lakes.
Herbivores (or Primary Consumers)
These organisms are heterotrophs that eat herbivores or other carnivores, and include coyotes, tigers, owls, and preying mantises. They can be secondary consumers (those that eat an herbivore), or tertiary consumers (those that eat a carnivore that has eaten a herbivore), and so on.
Carnivores (Secondary Consumers or Tertiary Consumers)
These organisms are heterotrophs that consume either autotrophs (primary producers) or consumers (herbivores and carnivores), and include bears and humans.
Omnivores
These organisms, such as crows, are heterotrophs that feed on recently dead organisms.
Scavengers
These organisms are heterotrophs that obtain energy by breaking down dead organisms into their inorganic form, such as bracket fungi that break down dead tissues and wastes into carbon, nitrogen, and other inorganic compounds and elements.
Decomposers
Energy flows through an ecosystem in the form of ____. As these are broken, energy is released, which then can be used by the organism or dissipated as heat.
carbon-carbon bonds
A second major process linking the biotic and abiotic constituents of an ecosystem is the flow of nutrients.
Nutrient Cycle
Unlike energy, which is not cycled, ___ are cycled in ecosystems.
Inorganic Nutrients
____ is the process by which inorganic materials, such as water, oxygen, carbon, calcium, and nitrogen, move through both the biotic communities (organisms) and the geological world (atmosphere, oceans, soil, and even rocks).
A biogeochemical cycle
Four Most Important Nutrient Cycle
Water Cycle
Nitrogen Cycle
Phosphorus Cycle
Oxygen-Carbon Cycle
A ____ is a linear sequence of organisms through which nutrients and energy pass as one organism eats another.
Food Chain
Levels in Food Chain
Producers
Primary Consumers
Higher-Level Consumers
Decomposers
Trophic Levels
First Trophic (Plants or Autotrophs)
Second Trophic (Herbivores)
Third Trophic (Carnivores)
Fourth Trophic (Top Carnivores)
In many ecosystems, the base, or foundation, of the food chain consists of (plants or phytoplankton), which are called ____.
Photosynthetic Organisms, Producers