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Environmental Gradient
An environmental gradient, or climate gradient, is a change in abiotic (non-living) factors through space (or time). Environmental gradients can be related to factors such as altitude, depth, temperature, soil humidity and precipitation. Often times, a multitude of biotic (living) factors are closely related to these gradients; as a result of a change in an environmental gradient, factors such as species abundance, population density, morphology, primary productivity, predation, and local adaptation may be impacted. Abiotic Influence The species distribution along environmental gradients has been studied intensively due to large databases of species presence data (e.g. GBIF). The abiotic factors that environmental gradients consist of can have a direct ramifications on organismal survival. Generally, organismal distribution is tied to those abiotic factors, but even an environmental gradient of one abiotic factor yields insight into how a species distribution might look. ...
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Abiotic Component
In biology and ecology, abiotic components or abiotic factors are non-living chemical and physical parts of the environment that affect living organisms and the functioning of ecosystems. Abiotic factors and the phenomena associated with them underpin biology as a whole. They affect a plethora of species, in all forms of environmental conditions, such as marine or land animals. Humans can make or change abiotic factors in a species' environment. For instance, fertilizers can affect a snail's habitat, or the greenhouse gases which humans utilize can change marine pH levels. Abiotic components include physical conditions and non-living resources that affect living organisms in terms of growth, maintenance, and reproduction. Resources are distinguished as substances or objects in the environment required by one organism and consumed or otherwise made unavailable for use by other organisms. Component degradation of a substance occurs by chemical or physical processes, e.g. hydroly ...
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Fitness (biology)
Fitness (often denoted w or ω in population genetics models) is the quantitative representation of individual reproductive success. It is also equal to the average contribution to the gene pool of the next generation, made by the same individuals of the specified genotype or phenotype. Fitness can be defined either with respect to a genotype or to a phenotype in a given environment or time. The fitness of a genotype is manifested through its phenotype, which is also affected by the developmental environment. The fitness of a given phenotype can also be different in different selective environments. With asexual reproduction, it is sufficient to assign fitnesses to genotypes. With sexual reproduction, recombination scrambles alleles into different genotypes every generation; in this case, fitness values can be assigned to alleles by averaging over possible genetic backgrounds. Natural selection tends to make alleles with higher fitness more common over time, resulting in Darwin ...
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Huisman–Olff–Fresco Models
Huisman–Olff–Fresco models (HOF models) are a hierarchical set of 5 models with increasing complexity, designated for fitting unimodal species response curves on environmental gradient An environmental gradient, or climate gradient, is a change in abiotic (non-living) factors through space (or time). Environmental gradients can be related to factors such as altitude, depth, temperature, soil humidity and precipitation. Often time .... A implementation of the model including extension for bimodal distributions exists as an R module downloadable from CRAN. References Oksanen's introduction of HOF models, and software to compute them* {{DEFAULTSORT:Huisman-Olff-Fresco models Ecological theories ...
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Restoration Ecology
Restoration ecology is the scientific study supporting the practice of ecological restoration, which is the practice of renewing and restoring degraded, damaged, or destroyed ecosystems and habitats in the environment by active human interruption and action. Effective restoration requires an explicit goal or policy, preferably an unambiguous one that is articulated, accepted, and codified. Restoration goals reflect societal choices from among competing policy priorities, but extracting such goals is typically contentious and politically challenging. Natural ecosystems provide ecosystem services in the form of resources such as food, fuel, and timber; the purification of air and water; the detoxification and decomposition of wastes; the regulation of climate; the regeneration of soil fertility; and the pollination of crops. These ecosystem processes have been estimated to be worth trillions of dollars annually. There is consensus in the scientific community that the current envi ...
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Thermocline
A thermocline (also known as the thermal layer or the metalimnion in lakes) is a thin but distinct layer in a large body of fluid (e.g. water, as in an ocean or lake; or air, e.g. an atmosphere) in which temperature changes more drastically with depth than it does in the layers above or below. In the ocean, the thermocline divides the upper mixed layer from the calm deep water below. Depending largely on season, latitude, and turbulent mixing by wind, thermoclines may be a semi-permanent feature of the body of water in which they occur, or they may form temporarily in response to phenomena such as the radiative heating/cooling of surface water during the day/night. Factors that affect the depth and thickness of a thermocline include seasonal weather variations, latitude, and local environmental conditions, such as tides and currents. Oceans Most of the heat energy of the sunlight that strikes the Earth is absorbed in the first few centimeters at the ocean's surface, which ...
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Gradient Analysis
Ordination or gradient analysis, in multivariate analysis, is a method complementary to data clustering, and used mainly in exploratory data analysis (rather than in hypothesis testing). Ordination orders objects that are characterized by values on multiple variables (multivariate objects) so that similar objects are near each other and dissimilar objects are farther from each other. Such relationships between the objects, on each of several axes (one for each variable), are then characterized numerically and/or graphically. Many ordination techniques exist, including principal components analysis (PCA), non-metric multidimensional scaling (NMDS), correspondence analysis (CA) and its derivatives ( detrended CA (DCA), canonical CA (CCA)), Bray–Curtis ordination, and redundancy analysis (RDA), among others. Contemporary developments for ordination focus on machine learning techniques or using statistical models instead. Applications Ordination can be used on the analysis of ...
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Cline (biology)
In biology, a cline (from the Greek κλίνειν ''klinein'', meaning "to lean") is a measurable gradient in a single character (or biological trait) of a species across its geographical range. First coined by Julian Huxley in 1938, the "character" of the cline referred to is usually genetic (e.g. allele frequency, blood type), or phenotypic (e.g. body size, skin pigmentation). Clines can show smooth, continuous gradation in a character, or they may show more abrupt changes in the trait from one geographic region to the next. A cline refers to a spatial gradient in a specific, singular trait, rather than a collection of traits; a single population can therefore have as many clines as it has traits, at least in principle. Additionally, Huxley recognised that these multiple independent clines may not act in concordance with each other. For example, it has been observed that in Australia, birds generally become smaller the further towards the north of the country they are found ...
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Biome
A biome () is a biogeographical unit consisting of a biological community that has formed in response to the physical environment in which they are found and a shared regional climate. Biomes may span more than one continent. Biome is a broader term than habitat and can comprise a variety of habitats. While a biome can cover large areas, a microbiome is a mix of organisms that coexist in a defined space on a much smaller scale. For example, the human microbiome is the collection of bacteria, viruses, and other microorganisms that are present on or in a human body. A biota is the total collection of organisms of a geographic region or a time period, from local geographic scales and instantaneous temporal scales all the way up to whole-planet and whole-timescale spatiotemporal scales. The biotas of the Earth make up the biosphere. Etymology The term was suggested in 1916 by Clements, originally as a synonym for '' biotic community'' of Möbius (1877). Later, it gained its c ...
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Environmental Justice
Environmental justice is a social movement to address the unfair exposure of poor and marginalized communities to harms from hazardous waste, resource extraction, and other land uses.Schlosberg, David. (2007) ''Defining Environmental Justice: Theories, Movements, and Nature''. Oxford University Press. The movement has generated hundreds of studies showing that exposure to environmental harms is inequitably distributed. The global environmental justice movement arises from place-based environmental conflicts in which local environmental defenders frequently confront multi-national corporations in resource extraction or other industries. Local outcomes of these conflicts are increasingly influenced by trans-national environmental justice networks. The movement began in the United States in the 1980s and was heavily influenced by the American civil rights movement. The original conception of environmental justice in the 1980s focused on harms to marginalised racial groups ...
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Fukushima Radiation Dose Map 2011-04-29
may refer to: Japan * Fukushima Prefecture, Japanese prefecture ** Fukushima, Fukushima, capital city of Fukushima Prefecture, Japan ***Fukushima University, national university in Japan ***Fukushima Station (Fukushima) in Fukushima, Fukushima **Fukushima Airport, airport serving northern and central Fukushima Prefecture, Japan **Fukushima Daini Nuclear Power Plant, another nuclear power plant in Fukushima Prefecture, Japan. Now being decommissioned **Fukushima Daiichi Nuclear Power Plant, a disabled nuclear power plant in Fukushima Prefecture, Japan *** Fukushima Daiichi nuclear disaster, 2011 nuclear disaster at the Fukushima nuclear power plant, Japan *** Fukushima disaster cleanup, clean-up activities following the nuclear accidents, Fukushima, Japan ** 2016 Fukushima earthquake ** 2021 Fukushima earthquake Hokkaido *Fukushima, Hokkaido Osaka *Fukushima-ku, Osaka, ward * Fukushima Station Nagano Prefecture *Kiso-Fukushima Station *Fukushima-juku, former post town ...
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Soil Respiration
Soil respiration refers to the production of carbon dioxide when soil organisms respire. This includes respiration of plant roots, the rhizosphere, microbes and fauna. Soil respiration is a key ecosystem process that releases carbon from the soil in the form of CO2. CO2 is acquired by plants from the atmosphere and converted into organic compounds in the process of photosynthesis. Plants use these organic compounds to build structural components or respire them to release energy. When plant respiration occurs below-ground in the roots, it adds to soil respiration. Over time, plant structural components are consumed by heterotrophs. This heterotrophic consumption releases CO2 and when this CO2 is released by below-ground organisms, it is considered soil respiration. The amount of soil respiration that occurs in an ecosystem is controlled by several factors. The temperature, moisture, nutrient content and level of oxygen in the soil can produce extremely disparate rates of resp ...
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Climate Change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global average temperature is more rapid than previous changes, and is primarily caused by humans burning fossil fuels. Fossil fuel use, deforestation, and some agricultural and industrial practices increase greenhouse gases, notably carbon dioxide and methane. Greenhouse gases absorb some of the heat that the Earth radiates after it warms from sunlight. Larger amounts of these gases trap more heat in Earth's lower atmosphere, causing global warming. Due to climate change, deserts are expanding, while heat waves and wildfires are becoming more common. Increased warming in the Arctic has contributed to melting permafrost, glacial retreat and sea ice loss. Higher temperatures are also causing m ...
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