Outline of ecology

• Nature – Natural, physical, or material world and its phenomena, or Natural environment – Living and non-living things on Earth
• Ecosystem – Community of living organisms together with the nonliving components of their environment, or Biome – Biogeographical unit with a particular biological community
  • Community (ecology) – Associated populations of species in a given area, or Biocoenosis – Interacting organisms living together in a habitat
    • Species – Basic unit of taxonomic classification, below genus
      • Population – All the organisms of a given species that live in a specified region
        • Organism – Individual living life form
• Biodiversity – Variety and variability of life forms
  • Food web – Natural interconnection of food chains

Ecology can also be classified on the basis of:

• the primary kinds of organism under study, e.g. animal ecology, plant ecology, insect ecology;
• the biomes principally studied, e.g. forest ecology, grassland ecology, desert ecology, benthic ecology, marine ecology, urban ecology;
• the geographic or climatic area, e.g. arctic ecology, tropical ecology;
• the spatial scale under consideration, e.g. macroecology, landscape ecology;
• the philosophical approach, e.g. systems ecology which adopts a holistic approach;
• the methods used, e.g. molecular ecology.

Ecology is a broad discipline comprising many subdisciplines. The field of ecology can be subdivided according to several classification schemes:

• Field ecology – Collection of information outside a laboratory, library or workplace setting –
• Quantitative ecology – application of advanced mathematical and statistical tools to perform ecological researchPages displaying wikidata descriptions as a fallback –
• Theoretical ecology – scientific discipline devoted to the study of ecological systems using theoretical methodsPages displaying wikidata descriptions as a fallback – the development of ecological theory, usually with mathematical, statistical and/or computer modeling tools.

• Global ecology – Global sum of all ecosystems on Earth –
• Macroecology – Study of relationships between organisms and their environment at large spatial scales –
• Microecology – Microbial ecology or ecology of a microhabitat.

Arranged from lowest to highest level of organisation:^[1]

• Autecology – ecological study of a single individual, population, or speciesPages displaying wikidata descriptions as a fallback – the study of individual organisms of a single species in relation to their environment;
• Synecology – Associated populations of species in a given areaPages displaying short descriptions of redirect targets – the study of homogenous or heterogenous groups of organisms in relation to their environment;
  • Population ecology – Sub-field of ecology – the study of homogenous groups of organisms related as a single species;
  • Community ecology – Associated populations of species in a given area – the study of heterogenous groups of organisms of multiple associated species;
  • Ecosystem ecology – Study of living and non-living components of ecosystems and their interactions.

• Human ecology – Study of the relationship between humans and their natural, social, and built environments –
• Animal ecology – Scientific study of the relationships between living animals and their environment –
• Insect ecology – The study of how insects interact with the surrounding environment –
• Microbial ecology – Study of the relationship of microorganisms with their environment –
• Plant ecology – The study of effect of the environment on the abundance and distribution of plants.

• Benthic ecology – Ecological region at the lowest level of a body of waterPages displaying short descriptions of redirect targets –
• Desert ecology – The study of interactions between both biotic and abiotic components of desert environments –
• Forest ecology – Study of interactions between the biota and environment in forests. –
• Grassland ecology – Area with vegetation dominated by grasses –
• Marine ecology – The study of the interactions between organisms and environment in the sea –
• Aquatic ecology – The study of interactions between organisms and the environment in water –
• Urban ecology – Scientific study of living organisms.

• Arctic ecology – Study of the relationships between biotic and abiotic factors in the arctic –
• Polar ecology – Relationship between plants and animals and a polar environment –
• Tropical ecology – Study of the relationships between the biotic and abiotic components of the tropics.

• Behavioral ecology – Study of the evolutionary basis for animal behavior due to ecological pressures –
• Chemical ecology – Study of chemically-mediated interactions between living organisms – which deals with the ecological role of biological chemicals used in a wide range of areas including defense against predators and attraction of mates;
• Disease ecology – Sub-discipline of ecology – which studies host-pathogen interactions, particularly those of infectious diseases, within the context of environmental factors;
• Ecophysiology – Study of adaptation of an organism's physiology to environmental conditions – which studies the interaction of physiological traits with the abiotic environment;
• Ecotoxicology – study of effects of released pollutants on the environment and biotaPages displaying wikidata descriptions as a fallback – which looks at the ecological role of toxic chemicals (often pollutants, but also naturally occurring compounds);
• Evolutionary ecology – Interaction of biology and evolution – or ecoevolution which looks at evolutionary changes in the context of the populations and communities in which the organisms exist;
• Fire ecology – Study of fire in ecosystems – which looks at the role of fire in the environment of plants and animals and its effect on ecological communities;
• Functional ecology – branch of ecologyPages displaying wikidata descriptions as a fallback – the study of the roles, or functions, that certain species (or groups thereof) play in an ecosystem;
• Genetic ecology – Study of genetic material in the environment –
• Landscape ecology – Science of relationships between ecological processes in the environment and particular ecosystems –
  • Landscape limnology – Spatially explicit study of lakes, streams, and wetlands as they interact with landscapes –
• Molecular ecology – Field of evolutionary biology –
• Paleoecology – Study of interactions between organisms and their environments across geologic timescales –
• Social ecology – Study of relationships between people and their environment –
• Soil ecology – Study of the interaction of soil and life – the ecology of the pedosphere –
• Sensory ecology – study of how organisms acquire, process, and respond to information from their environmentPages displaying wikidata descriptions as a fallback –
• Spatial ecology – Study of the distribution or space occupied by species –
• Thermal ecology – study of the interactions between temperature and organismsPages displaying wikidata descriptions as a fallback – the study of the relationship between temperature and organisms.

• Agroecology – Study of ecological processes in agriculture –
• Applied ecology – sub-field within ecology that considers the application of the science of ecology to real-world (usually management) questionsPages displaying wikidata descriptions as a fallback – the practice of employing ecological principles and understanding to solve real world problems (includes agroecology and conservation biology);
  • Conservation ecology – Study of threats to biological diversity – which studies how to reduce the risk of species extinction;
  • Restoration ecology – Scientific study of renewing and restoring ecosystemsPages displaying short descriptions of redirect targets – which attempts to understand the ecological basis needed to restore impaired or damaged ecosystems;
• Biogeochemistry – Study of chemical cycles of the earth that are either driven by or influence biological activity –
• Biogeography – Study of distribution of species –
• Ecological design – Design approach sensitive to environmental impacts –
• Ecological economics – Interdependence of human economies and natural ecosystems –
• Ecological engineering – Environmental engineering –
• Ecological anthropology – Study of cultural adaptations to environments –
  • Festive ecology – Study of ecology and cultural events –
• Ecological health – term in medicine about management of environmental factors that may reduce the risk of unhealthy behaviorPages displaying wikidata descriptions as a fallback –
• Ecosophy – Philosophy of ecological harmony or equilibrium as developed by Arne Næss or Félix Guattari –
• Environmental psychology – Academic study of the mind's relationship to one's immediate surroundings –
• Natural history – Study of organisms including plants or animals in their environment –
• Systems ecology – Holistic approach to the study of ecological systems –

Ecology has also inspired (and lent its name to) other non-biological disciplines such as:

• Media ecology
• Industrial ecology
• Information ecology

• Biosphere – Global sum of all ecosystems on Earth

Biogeographic realm – Broadest biogeographic division of Earth's land surface. The World Wildlife Fund (WWF) developed a system of eight biogeographic realms (ecozones):

• Nearctic – Biogeographic realm encompassing temperate North AmericaPages displaying short descriptions of redirect targets 22.9 mil. km² (including most of North America)
• Palearctic – Biogeographic realm covering most of EurasiaPages displaying short descriptions of redirect targets 54.1 mil. km² (including the bulk of Eurasia and North Africa)
• Afrotropical – One of Earth's eight biogeographic realmsPages displaying short descriptions of redirect targets 22.1 mil. km² (including Sub-Saharan Africa)
• Indomalayan – One of the Earth's eight ecozonesPages displaying short descriptions of redirect targets 7.5 mil. km² (including the South Asian subcontinent and Southeast Asia)
• Australasian – One of the Earth's eight biogeographic realms 7.7 mil. km² (including Australia, New Guinea, and neighbouring islands). The northern boundary of this zone is known as the Wallace line.
• Neotropical – One of Earth's eight biogeographic realmsPages displaying short descriptions of redirect targets 19.0 mil. km² (including South America and the Caribbean)
• Oceanian – Terrestrial biogeographic realm 1.0 mil. km² (including Polynesia, Fiji and Micronesia)
• Antarctic – One of Earth's eight biogeographic realms 0.3 mil. km² (including Antarctica).

Ecoregion – Ecologically and geographically defined area that is smaller than a bioregion

The World has over 800 terrestrial ecoregions. See Lists of ecoregions by country.

History of ecology

• History of human ecology

• Ecological succession – Process of change in the species structure of an ecological community over time
  • Primary succession – Gradual growth and change of an ecosystem on new substrate
    • Pioneer species – First species to colonize or inhabit damaged ecosystems
    • Ruderal species – Plant species that is first to colonize disturbed lands
    • Supertramp – Any type of animal which follows the strategy of high dispersion among many different habitats
  • Secondary succession – Redevelopment of an encology after an event that changes it radically
• Carrying capacity – Maximum population size of a species that an environment can support
  • Ecological collapse – Ecological communities abruptly losing biodiversity, often irreversiblyPages displaying short descriptions of redirect targets
• Competitive exclusion principle – Ecology proposition
• Ecological yield – Harvestable population growth in an ecosystem
• Autotroph – Organism type
• Bacteria – Domain of microorganisms
• Bioinvader – Organism occurring in a new habitat
• Biomass – Biological material from either living (see ecology) or recently living organisms (see bioenergy)
• Biotic material – Any material that originates from living organisms
• Carbon cycle – Natural processes of carbon exchange
• Climate – Statistics of weather conditions in a given region over long periods
• Ecological selection – Natural selection without sexual selection
• Gaia hypothesis – Paradigm that living organisms interact with their surroundings in a self-regulating system
• Natural resource – Resources that exist without actions of humankind.
• Monoculture – Farms producing only one crop at a time
• Decomposition – Process in which organic substances are broken down into simpler organic matter
  • Organic matter – Matter composed of organic compounds
• Inorganic substance – A substance lacking organic constituents
  • Detritus – Dead particulate organic material
  • Biodegradation – Decomposition by living organisms
• Ecological crisis – Change to the environment that destabilizes the continued survival of a population
• Ecological extinction – Ecology term
• Ecophagy – The literal consumption of an ecosystem
• Ecological niche – Fit of a species living under specific environmental conditions
• Niche differentiation – The process by which competing species use the environment differently in a way that helps them to coexist.
• Biological interaction – Effect that organisms have on other organisms
  • Neutralism – A relationship between two species that interact but do not affect each other
  • Amensalism – Close, long-term biological interaction between distinct organisms (usually species)Pages displaying short descriptions of redirect targets
  • Ecological facilitation – Species interactions that benefit at least one of the participants and cause harm to neither
    • Mutualism – Mutually beneficial interaction between species
    • Commensalism – Beneficial symbiosis between species
  • Coexistence theory – A framework to understand and explain how ecologically similar species can coexist without competitively excluding each other
  • Competition – Interaction where the fitness of one organism is lowered by the presence of another organism
  • Predation – Biological interaction
  • Parasitism – Relationship between species where one organism lives on or in another organism, causing it harm
• Sexecology – Activism based around ecofetishism

• Bibliography of ecology – List of publications on the topic of biology
• Biology – Science that studies life
  • Outline of biology – Outline of subdisciplines within biology
  • Index of biology articles

• What is Ecology?
• Fundamentals of Ecology Textbook-style investigation to the economy of nature, breaks down in four chapters from Population to Ecosystem.
• Ecology (Stanford Encyclopedia of Philosophy)