Ecological successionEcological succession is the process of change in the species that make up an ecological community over time. The process of succession occurs either after the initial colonization of a newly created habitat, or after a disturbance substantially alters a pre-existing habitat. Succession that begins in new habitats, uninfluenced by pre-existing communities, is called primary succession, whereas succession that follows disruption of a pre-existing community is called secondary succession.
PyrogeographyPyrogeography is the study of the past, present, and projected distribution of wildfire. Wildland fire occurs under certain conditions of climate, vegetation, topography, and sources of ignition, such that it has its own biogeography, or pattern in space and time. The earliest published evidence of the term appears to be in the mid-1990s, and the meaning was primarily related to mapping fires The current understanding of pyrogeography emerged in the 2000s as a combination of biogeography and fire ecology, facilitated by the availability of global-scale datasets of fire occurrence, vegetation cover, and climate.
Fire regimeA fire regime is the pattern, frequency, and intensity of the bushfires and wildfires that prevail in an area over long periods of time. It is an integral part of fire ecology, and renewal for certain types of ecosystems. A fire regime describes the spatial and temporal patterns and ecosystem impacts of fire on the landscape, and provides an integrative approach to identifying the impacts of fire at an ecosystem or landscape level. If fires are too frequent, plants may be killed before they have matured, or before they have set sufficient seed to ensure population recovery.
Bioenergy with carbon capture and storageBioenergy with carbon capture and storage (BECCS) is the process of extracting bioenergy from biomass and capturing and storing the carbon, thereby removing it from the atmosphere. BECCS can be a "negative emissions technology" (NET). The carbon in the biomass comes from the greenhouse gas carbon dioxide (CO2) which is extracted from the atmosphere by the biomass when it grows. Energy ("bioenergy") is extracted in useful forms (electricity, heat, biofuels, etc.
Intermediate disturbance hypothesisThe intermediate disturbance hypothesis (IDH) suggests that local species diversity is maximized when ecological disturbance is neither too rare nor too frequent. At low levels of disturbance, more competitive organisms will push subordinate species to extinction and dominate the ecosystem. At high levels of disturbance, due to frequent forest fires or human impacts like deforestation, all species are at risk of going extinct.
Carbon capture and storageCarbon capture and storage (CCS) is a process in which a relatively pure stream of carbon dioxide (CO2) from industrial sources is separated, treated and transported to a long-term storage location. For example, the carbon dioxide stream that is to be captured can result from burning fossil fuels or biomass. Usually the CO2 is captured from large point sources, such as a chemical plant or biomass plant, and then stored in an underground geological formation. The aim is to reduce greenhouse gas emissions and thus mitigate climate change.
Aquatic ecosystemAn aquatic ecosystem is an ecosystem found in and around a body of water, in contrast to land-based terrestrial ecosystems. Aquatic ecosystems contain communities of organisms—aquatic life—that are dependent on each other and on their environment. The two main types of aquatic ecosystems are marine ecosystems and freshwater ecosystems. Freshwater ecosystems may be lentic (slow moving water, including pools, ponds, and lakes); lotic (faster moving water, for example streams and rivers); and wetlands (areas where the soil is saturated or inundated for at least part of the time).
Primary successionPrimary succession is the beginning step of ecological succession after an extreme disturbance, which usually occurs in an environment devoid of vegetation and other organisms. These environments are typically lacking in soil, as disturbances like lava flow or retreating glaciers scour the environment clear of nutrients. In contrast, secondary succession occurs on substrates that previously supported vegetation before an ecological disturbance.
Biogeochemical cycleA biogeochemical cycle, or more generally a cycle of matter, is the movement and transformation of chemical elements and compounds between living organisms, the atmosphere, and the Earth's crust. Major biogeochemical cycles include the carbon cycle, the nitrogen cycle and the water cycle. In each cycle, the chemical element or molecule is transformed and cycled by living organisms and through various geological forms and reservoirs, including the atmosphere, the soil and the oceans.
River ecosystemRiver ecosystems are flowing waters that drain the landscape, and include the biotic (living) interactions amongst plants, animals and micro-organisms, as well as abiotic (nonliving) physical and chemical interactions of its many parts. River ecosystems are part of larger watershed networks or catchments, where smaller headwater streams drain into mid-size streams, which progressively drain into larger river networks. The major zones in river ecosystems are determined by the river bed's gradient or by the velocity of the current.