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Bark Pocket
Bark pockets are patches or inclusions of bark partially or fully embedded in the wood of a tree. They can also be used as biomonitors. Bark pockets are considered a nuisance in the lumber industry because they are considered a defect, and lower the grade of the wood. Bark pockets can also weaken tree forks, and can result in damage to the junction under stress. Formation Bark pockets can be formed by inosculation, formation of a tree fork, encapsulation of a branch, joining together of an uneven trunk, or encapsulation of another object. During inosculation, the bark trapped between the two joining trunk becomes surrounded with wood once the trunks fuse. The resulting bark pocket formed during inosculation or in a tree fork is referred to as included bark. When a branch is encapsulated, the outer bark on the branch may remain inside the wood of the tree, as the trunk widens and grows around the branch. As biomonitors Bark pockets can be used as an indicator of air pollutants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dual Pith Pinus Sylvestris Beentree
Dual or Duals may refer to: Paired/two things * Dual (mathematics), a notion of paired concepts that mirror one another ** Dual (category theory), a formalization of mathematical duality *** see more cases in :Duality theories * Dual (grammatical number), a grammatical category used in some languages * Dual county, a Gaelic games county which in both Gaelic football and hurling * Dual diagnosis, a psychiatric diagnosis of co-occurrence of substance abuse and a mental problem * Dual fertilization, simultaneous application of a P-type and N-type fertilizer * Dual impedance, electrical circuits that are the dual of each other * Dual SIM cellphone supporting use of two SIMs * Aerochute International Dual a two-seat Australian powered parachute design Acronyms and other uses * Dual (brand), a manufacturer of Hifi equipment * DUAL (cognitive architecture), an artificial intelligence design model * DUAL algorithm, or diffusing update algorithm, used to update Internet protocol routing tab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biomonitoring
In analytical chemistry, biomonitoring is the measurement of the body burden of toxic chemical compounds, elements, or their metabolites, in biological substances. Often, these measurements are done in blood and urine. Biomonitoring is performed in both environmental health, and in occupational safety and health as a means of exposure assessment and workplace health surveillance. The two best established environmental biomonitoring programs in representative samples of the general population are those of the United States and Germany, although population-based programs exist in a few other countries. In 2001, the U.S. Centers for Disease Control and Prevention (CDC) began to publish its biennial ''National Report on Human Exposure to Environmental Chemicals'', which reports a statistically representative sample of the U.S. population. Overview Biomonitoring involves the use of organisms to assess environmental contamination, such as of surrounding air or water. It can be done ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tree Fork
A tree fork is a bifurcation in the trunk of a tree giving rise to two roughly equal diameter branches. These forks are a common feature of tree crowns. The wood grain orientation at the top of a tree fork is such that the wood's grain pattern most often interlocks to provide sufficient mechanical support. A common "malformation" of a tree fork is where bark has formed within the join, often caused by natural bracing occurring higher up in the crown of the tree, and these bark-included junctions often have a heightened risk of failure, especially when bracing branches are pruned out or are shaded out from the tree's crown. Definition In arboriculture, junctions in the crown structure of trees are frequently categorised as either branch-to-stem attachments or co-dominant stems. Co-dominant stems are where the two or more arising branches emerging from the junction are of near equal diameter and this type of junction in a tree is often referred to in layman's terms as 'a tree ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Branch Collar
A branch collar is the "shoulder" between the branch and trunk of woody plants; the inflammation formed at the base of the branch is caused by annually overlapping trunk tissue. The shape of the branch collar is due to two separate growth patterns, initially the branch grows basipetally, followed by seasonal trunk growth which envelops the branch. Branch collars serve as a strong foundation to the branch, and its orientation and internal characteristics allow the branch to withstand stress from numerous directions. Functionally the branch collars also influence the conductivity of nutrients and growth patterns. The branch collar which provides a protective barrier to prevent infection and decay, can also be useful in diagnosing bacterial diseases. Proper pruning techniques should accommodate for the branch collar structure, as by damaging the tree it is likely to decay or become diseased. Definition In arboriculture, the "shoulder" junction structure between the branch and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inosculation
Inosculation is a natural phenomenon in which trunks, branches or roots of two trees grow together in a manner biologically similar to the artificial process of grafting. The term is derived from the Latin roots ''in'' + '' ōsculārī'', "to kiss into/inward/against" or etymologically and more illustratively "to make a small mouth inward/into/against"; trees having undergone the process are referred to in forestry as gemels, from the Latin word meaning "a pair". It is most common for branches of two trees of the same species to grow together, though inosculation may be noted across related species. The branches first grow separately in proximity to each other until they touch. At this point, the bark on the touching surfaces is gradually abraded away as the trees move in the wind. Once the cambium of two trees touches, they sometimes self-graft and grow together as they expand in diameter. Inosculation customarily results when tree limbs are braided or pleached. The term ''in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indicator Plant
A bioindicator is any species (an indicator species) or group of species whose function, population, or status can reveal the qualitative status of the environment. The most common indicator species are animals. For example, copepods and other small water crustaceans that are present in many water bodies can be monitored for changes (biochemical, physiological, or behavioural) that may indicate a problem within their ecosystem. Bioindicators can tell us about the cumulative effects of different pollutants in the ecosystem and about how long a problem may have been present, which physical and chemical testing cannot. A biological monitor or biomonitor is an organism that provides quantitative information on the quality of the environment around it. Therefore, a good biomonitor will indicate the presence of the pollutant and can also be used in an attempt to provide additional information about the amount and intensity of the exposure. A biological indicator is also the name given ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heavy Metals
upright=1.2, Crystals of osmium, a heavy metal nearly twice as dense as lead">lead.html" ;"title="osmium, a heavy metal nearly twice as dense as lead">osmium, a heavy metal nearly twice as dense as lead Heavy metals are generally defined as metals with relatively high density, densities, atomic weights, or atomic numbers. The criteria used, and whether metalloids are included, vary depending on the author and context. In metallurgy, for example, a heavy metal may be defined on the basis of density, whereas in physics the distinguishing criterion might be atomic number, while a chemist would likely be more concerned with chemical property, chemical behaviour. More specific definitions have been published, but none of these have been widely accepted. The definitions surveyed in this article encompass up to 96 out of the 118 known chemical elements; only mercury, lead and bismuth meet all of them. Despite this lack of agreement, the term (plural or singular) is widely used in s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polycyclic Aromatic Hydrocarbons
A polycyclic aromatic hydrocarbon (PAH) is a class of organic compounds that is composed of multiple aromatic rings. The simplest representative is naphthalene, having two aromatic rings and the three-ring compounds anthracene and phenanthrene. PAHs are uncharged, non-polar and planar. Many are colorless. Many of them are found in coal and in oil deposits, and are also produced by the combustion of organic matter—for example, in engines and incinerators or when biomass burns in forest fires. Polycyclic aromatic hydrocarbons are discussed as possible starting materials for abiotic syntheses of materials required by the earliest forms of life. Nomenclature and structure The terms polyaromatic hydrocarbon or polynuclear aromatic hydrocarbon are also used for this concept. By definition, polycyclic aromatic hydrocarbons have multiple rings, precluding benzene from being considered a PAH. Some sources, such as the US EPA and CDC, consider naphthalene to be the simplest PAH. Other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
