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Canopy Soils
Canopy soils, also known as arboreal soils, exist in areas of the forest canopy where branches, crevices, or some other physical feature on a tree can accumulate organic matter, such as leaves or fine branches. Eventually, this organic matter weathers into some semblance of a soil, and can reach depths of 30 cm in some temperate rainforests. Epiphytes can take root in the canopy soil, which accelerates the development of the soil by adding organic material and physically breaking up material with their root system. The nutrients that become stored within canopy soils can then be utilized by the epiphytes that grow in them, and even the tree that the canopy soil is accumulating in through the growth of canopy roots. This storage allows nutrients to be more closely cycled through an ecosystem, and prevents nutrients from being washed out of the system. The nitrogen cycle is most prevalent in canopy soil ecosystems with regards to the biogeochemical cycles that naturally exist within ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canopy (biology)
In biology, the canopy is the aboveground portion of a plant community, plant cropping or crop, formed by the collection of individual Crown (botany), plant crowns. In forest ecology, the canopy is the upper layer or habitat zone, formed by mature tree crowns and including other biological organisms (epiphytes, lianas, Arboreal, arboreal animals, etc.). The communities that inhabit the canopy layer are thought to be involved in maintaining forest diversity, Ecological resilience, resilience, and functioning. Shade trees normally have a dense canopy that blocks light from lower growing plants. Early observations of canopies were made from the ground using binoculars or by examining fallen material. Researchers would sometimes erroneously rely on extrapolation by using more reachable samples taken from the understory. In some cases, they would use unconventional methods such as chairs suspended on vines or hot-air dirigibles, among others. Modern technology, including adapted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Last Glacial Maximum
The Last Glacial Maximum (LGM), also referred to as the Last Glacial Coldest Period, was the most recent time during the Last Glacial Period where ice sheets were at their greatest extent between 26,000 and 20,000 years ago. Ice sheets covered much of Northern North America, Northern Europe, and Asia and profoundly affected Earth's climate by causing a major expansion of deserts, along with a large drop in sea levels. Based on changes in position of ice sheet margins dated via cosmogenic nuclide, terrestrial cosmogenic nuclides and radiocarbon dating, growth of ice sheets in the southern hemisphere commenced 33,000 years ago and maximum coverage has been estimated to have occurred sometime between 26,500 years ago and 20,000 years ago. After this, deglaciation caused an abrupt rise in sea level. Decline of the West Antarctica ice sheet occurred between 14,000 and 15,000 years ago, consistent with evidence for another abrupt rise in the sea level about 14,500 years ago. Glacier fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forestry
Forestry is the science and craft of creating, managing, planting, using, conserving and repairing forests and woodlands for associated resources for human and Natural environment, environmental benefits. Forestry is practiced in plantations and natural Stand level modelling, stands. The science of forestry has elements that belong to the biological, physical, social, political and managerial sciences. Forest management plays an essential role in the creation and modification of habitats and affects ecosystem services provisioning. Modern forestry generally embraces a broad range of concerns, in what is known as multiple-use management, including: the provision of timber, fuel wood, wildlife habitat, natural Water resources, water quality management, recreation, landscape and community protection, employment, aesthetically appealing landscapes, biodiversity management, watershed management, erosion control, and preserving forests as "Carbon dioxide sink, sinks" for Earth's atmosp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Old-growth Forest
An old-growth forest or primary forest is a forest that has developed over a long period of time without disturbance. Due to this, old-growth forests exhibit unique ecological features. The Food and Agriculture Organization of the United Nations defines primary forests as naturally regenerated forests of native tree species where there are no clearly visible indications of human activity and the ecological processes are not significantly disturbed. One-third (34 percent) of the world's forests are primary forests. Old-growth features include diverse tree-related structures that provide diverse wildlife habitats that increases the biodiversity of the forested ecosystem. Virgin or first-growth forests are old-growth forests that have never been logged. The concept of diverse tree structure includes multi-layered canopies and canopy gaps, greatly varying tree heights and diameters, and diverse tree species and classes and sizes of woody debris., the world has of primary forest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biodiversity
Biodiversity is the variability of life, life on Earth. It can be measured on various levels. There is for example genetic variability, species diversity, ecosystem diversity and Phylogenetics, phylogenetic diversity. Diversity is not distributed evenly on Earth. It is greater in the tropics as a result of the warm climate and high primary productivity in the region near the equator. Tropical forest ecosystems cover less than one-fifth of Earth's terrestrial area and contain about 50% of the world's species. There are latitudinal gradients in species diversity for both marine and terrestrial taxa. Since Abiogenesis, life began on Earth, six major mass extinctions and several minor events have led to large and sudden drops in biodiversity. The Phanerozoic aeon (the last 540 million years) marked a rapid growth in biodiversity via the Cambrian explosion. In this period, the majority of Multicellular organism, multicellular Phylum, phyla first appeared. The next 400 mil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen Fixation
Nitrogen fixation is a chemical process by which molecular dinitrogen () is converted into ammonia (). It occurs both biologically and abiological nitrogen fixation, abiologically in chemical industry, chemical industries. Biological nitrogen fixation or ''diazotrophy'' is catalyzed by enzymes called nitrogenases. These enzyme complexes are encoded by the Nif gene, ''Nif'' genes (or ''Nif'' homologs) and contain iron, often with a second metal (usually molybdenum, but sometimes vanadium). Some nitrogen-fixing bacteria have symbiotic relationships with plants, especially legumes, mosses and aquatic ferns such as ''Azolla''. Looser non-symbiotic relationships between diazotrophs and plants are often referred to as associative, as seen in nitrogen fixation on rice roots. Nitrogen fixation occurs between some termites and fungus, fungi. It occurs naturally in the air by means of NOx, NOx production by lightning. Fixed nitrogen is essential to life on Earth. Organic compounds such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbiotic Relationship
Symbiosis (Ancient Greek : living with, companionship < : together; and ''bíōsis'': living) is any type of a close and long-term biological interaction, between two s of different . The two organisms, termed symbionts, can for example be in mutualistic, commensalistic, or parasitic relationships. In 1879, [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrification
''Nitrification'' is the biological oxidation of ammonia to nitrate via the intermediary nitrite. Nitrification is an important step in the nitrogen cycle in soil. The process of complete nitrification may occur through separate organisms or entirely within one organism, as in comammox bacteria. The transformation of ammonia to nitrite is usually the rate limiting step of nitrification. Nitrification is an aerobic process performed by small groups of autotrophic bacteria and archaea. Microbiology Ammonia oxidation The process of nitrification begins with the first stage of ammonia oxidation, where ammonia (NH3) or ammonium (NH4+) get converted into nitrite (NO2−). This first stage is sometimes known as nitritation. It is performed by two groups of organisms, ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA). Ammonia-Oxidizing Bacteria Ammonia-Oxidizing Bacteria (AOB) are typically Gram-negative bacteria and belong to Betaproteobacteria and Gammaproteob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen Cycling
The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmospheric, terrestrial, and marine ecosystems. The conversion of nitrogen can be carried out through both biological and physical processes. Important processes in the nitrogen cycle include fixation, ammonification, nitrification, and denitrification. The majority of Earth's atmosphere (78%) is atmospheric nitrogen, making it the largest source of nitrogen. However, atmospheric nitrogen has limited availability for biological use, leading to a scarcity of usable nitrogen in many types of ecosystems. The nitrogen cycle is of particular interest to ecologists because nitrogen availability can affect the rate of key ecosystem processes, including primary production and decomposition. Human activities such as fossil fuel combustion, use of artificial nitrogen fertilizers, and release of nitrogen in wastewater have dramatically altered the global nitr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fascicularia
''Fascicularia'' is a monotypic genus of flowering plants in the pineapple family Bromeliaceae, subfamily Bromelioideae. The genus name is from the Latin ''fasciculus'' (bundle) and ''arius'' (pertaining to). Only one species is known, ''Fascicularia bicolor''. It is endemic to Chile and reportedly naturalized in France and the extreme south and west of Great Britain. In the wild, all ''Fascicularias'' are saxicolous (growing on rocks) or epiphyte An epiphyte is a plant or plant-like organism that grows on the surface of another plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphyt ...s. It is cultivated in gardens for the dramatic bright crimson colour of its leaves contrasting with the blue inflorescence. The edible fruits are similar to those of the species '' Greigia sphacelata'', but smaller; They are consumed in the same way as these. Subspecies Two subspecie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecosystem Engineer
An ecosystem engineer is any species that creates, significantly modifies, maintains or destroys a habitat. These organisms can have a large impact on species richness and landscape-level heterogeneity of an area. As a result, ecosystem engineers are important for maintaining the health and stability of the environment they are living in. Since all organisms impact the environment they live in one way or another, it has been proposed that the term "ecosystem engineers" be used only for keystone species whose behavior very strongly affects other organisms. Types Jones et al. identified two different types of ecosystem engineers: Allogenic engineers Allogenic engineers modify the biophysical environment by mechanically changing living or nonliving materials from one form to another. Beavers are the original model for ecosystem engineers; in the process of clearcutting and damming, beavers alter their ecosystem extensively. The addition of a dam will change both the distribution ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abiotic Factors
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 terrestrial 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. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
