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Pit-and-mound Topography
Pit and mounds are small, persistent microtopographical features that present themselves after a disturbance event occurs and uproots trees via windthrow. The uprooted tree falls, and a pit forms in the forest floor where the root mass and associated soil matrix used to be. Eventually after a period of time in which the roots decay, the associated soil matrix that was pulled out of the ground with the roots falls back to the ground, creating a corresponding mound. Formation of a pit A pit, as defined above, is formed when pressure is applied to the trunk and crown of the tree that is more powerful than the root and associated soil's ability to hold the tree upright and in place and knocks the tree down. This toppling of the tree can be caused by a multitude of different types of forest disturbance. Wind may blow the tree down; snow may accumulate and put excessive weight on the tree; the tree's roots may have decayed to a point where they are not strong enough to hold the tree up ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Windthrow
In forestry, windthrow refers to trees uprooted by wind. Breakage of the tree bole (botany), bole (trunk) instead of uprooting is called windsnap. Blowdown refers to both windthrow and windsnap. Causes Windthrow is common in all forested parts of the world that experience storms or high wind speeds. The risk of windthrow to a tree is related to the tree's size (height and diameter), the 'sail area' presented by its crown, the anchorage provided by its roots, its exposure to the wind, and the local wind climate. A common way of quantifying the risk of windthrow to a forest area is to model the probability or 'return time' of a wind speed that would damage those trees at that location. Another potential method is the detection of scattered windthrow based on satellite images. Tree senescence can also be a factor, where multiple factors contributing to the declining health of a tree reduce its anchorage and therefore increase its susceptibility to windthrow. The resulting dama ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forest Disturbance
Forest dynamics are the underlying physical and biological forces that shape and change a forest ecosystem. The continuous state of change in forests can be summarized with two basic elements: disturbance and succession. Disturbance Forest disturbances are events that cause change in the structure and composition of a forest ecosystem, beyond the growth and death of individual organisms. Disturbances can vary in frequency and intensity, and include natural disasters such as fire, landslides, wind, volcanic eruptions, rare meteor impacts, outbreaks of insects, fungi, and other pathogens, animal-caused effects such as grazing and trampling, and anthropogenic disturbances such as warfare, logging, pollution, the clearing of land for urbanization or agriculture, and the introduction of invasive species. Not all disturbances are destructive or negative to the overall forest ecosystem. Many natural disturbances allow for renewal and growth and often release necessary nutrients. Sma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photosynthetically Active Radiation
Photosynthetically active radiation (PAR) designates the spectral range (wave band) of solar radiation from 400 to 700 nanometers that photosynthetic organisms are able to use in the process of photosynthesis. This spectral region corresponds more or less with the range of light visible to the human eye. Photons at shorter wavelengths tend to be so energetic that they can be damaging to cells and tissues, but are mostly filtered out by the ozone layer in the stratosphere. Photons at longer wavelengths do not carry enough energy to allow photosynthesis to take place. Other living organisms, such as cyanobacteria, purple bacteria, and heliobacteria, can exploit solar light in slightly extended spectral regions, such as the near-infrared. These bacteria live in environments such as the bottom of stagnant ponds, sediment and ocean depths. Because of their pigments, they form colorful mats of green, red and purple. Chlorophyll, the most abundant plant pigment, is most efficient in ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coarse Woody Debris
Coarse woody debris (CWD) or coarse woody habitat (CWH) refers to fallen dead trees and the remains of large branches on the ground in forests and in rivers or wetlands.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p, p. 225-227. A dead standing tree, known as a Snag (ecology), snag, provides many of the same functions as coarse woody debris. The minimum size required for woody debris to be defined as "coarse" varies by author, ranging from in diameter. Since the 1970s, Forest management, forest managers worldwide have considered it best environmental practice to allow dead trees and woody debris to remain in woodlands, biogeochemical cycle, recycling nutrients trapped in the wood and providing heterotrophic nutrition, food and habitat for a wide range of organisms, thereby improving biodiversity. The amount of coarse woody debris is an important criterion for the evaluation and restoration of temperate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrofauna
Fauna (: faunae or faunas) is all of the animal life present in a particular region or time. The corresponding terms for plants and fungi are ''flora'' and ''funga'', respectively. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. Zoologists and paleontologists use ''fauna'' to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess Shale fauna". Paleontologists sometimes refer to a sequence of faunal stages, which is a series of rocks all containing similar fossils. The study of animals of a particular region is called faunistics. Etymology ''Fauna'' comes from the name Fauna, a Roman goddess of earth and fertility, the Roman god Faunus, and the related forest spirits called Fauns. All three words are cognates of the name of the Greek god Pan, and ''panis'' is the Modern Greek equivalent of fauna (πανίς or rather πανίδα). ''Fauna'' is also the word for a boo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earthworm
An earthworm is a soil-dwelling terrestrial invertebrate that belongs to the phylum Annelida. The term is the common name for the largest members of the class (or subclass, depending on the author) Oligochaeta. In classical systems, they were in the order of Opisthopora since the male pores opened posterior to the female pores, although the internal male segments are anterior to the female. Theoretical cladistic studies have placed them in the suborder Lumbricina of the order Haplotaxida, but this may change. Other slang names for earthworms include "dew-worm", "rainworm", "nightcrawler", and "angleworm" (from its use as angling hookbaits). Larger terrestrial earthworms are also called megadriles (which translates to "big worms") as opposed to the microdriles ("small worms") in the semiaquatic families Tubificidae, Lumbricidae and Enchytraeidae. The megadriles are characterized by a distinct clitellum (more extensive than that of microdriles) and a vascular system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temperate Rainforest
Temperate rainforests are rainforests with coniferous or Broad-leaved tree, broadleaf forests that occur in the temperate zone and receive heavy rain. Temperate rainforests occur in oceanic moist regions around the world: the Pacific temperate rainforests of North American Pacific Northwest as well as the Appalachian temperate rainforest in the Appalachian region of the United States; the Valdivian temperate rainforests of southwestern South America; the rainforests of New Zealand and southeastern Australia; northwest Europe (small pockets in Great Britain and larger areas in Ireland, southern Norway, northern Iberia and Brittany); southern Japan; the Black Sea–Caspian Sea region from the southeasternmost coastal zone of the Bulgarian Black Sea Coast, Bulgarian coast, through Turkey, to Georgia (country), Georgia, and northern Iran. The moist conditions of temperate rainforests generally have an understory of mosses, ferns and some shrubs and berries. Temperate rainforests can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Belgium
Belgium, officially the Kingdom of Belgium, is a country in Northwestern Europe. Situated in a coastal lowland region known as the Low Countries, it is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to the south, and the North Sea to the west. Belgium covers an area of and has a population of more than 11.8 million; its population density of ranks List of countries and dependencies by population density, 22nd in the world and Area and population of European countries, sixth in Europe. The capital and Metropolitan areas in Belgium, largest metropolitan region is City of Brussels, Brussels; other major cities are Antwerp, Ghent, Charleroi, Liège, Bruges, Namur, and Leuven. Belgium is a parliamentary system, parliamentary constitutional monarchy with a complex Federation, federal system structured on regional and linguistic grounds. The country is divided into three highly autonomous Communities, regions and language areas o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temperate Rainforests Of Eastern Canada
In geography, the temperate climates of Earth occur in the middle latitudes (approximately 23.5° to 66.5° N/S of the Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout the year and more distinct seasonal changes compared to tropical climates, where such variations are often small; they usually differ only in the amount of precipitation. In temperate climates, not only do latitudinal positions influence temperature changes, but various sea currents, prevailing wind direction, continentality (how large a landmass is) and altitude also shape temperate climates. The Köppen climate classification defines a climate as "temperate" C, when the mean temperature is above but below in the coldest month to account for the persistence of frost. However, some adaptations of Köppen set the minimum at . Continental climates are classified as D and considered to be varieties of temperate climates, h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southeast Alaska
Southeast Alaska, often abbreviated to southeast or southeastern, and sometimes called the Alaska(n) panhandle, is the southeastern portion of the U.S. state of Alaska, bordered to the east and north by the northern half of the Canadian province of British Columbia (and a small part of Yukon). The majority of southeast Alaska is situated in Tlingit Aaní, much of which is part of the Tongass National Forest, the United States' largest national forest. In many places, the international border runs along the crest of the Boundary Ranges of the Coast Mountains (see Alaska boundary dispute). The region is noted for its scenery and mild, rainy climate. The largest cities in the region are Juneau, Sitka, and Ketchikan. This region is also home to Hyder, the easternmost town in Alaska. Geography Southeast Alaska has a land area of , comprising much of the Alexander Archipelago. The largest islands are, from North to South, Chichagof Island, Admiralty Island, Baranof Is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forests
A forest is an ecosystem characterized by a dense community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' Food and Agriculture Organization (FAO) defines a forest as, "Land spanning more than 0.5 hectares with trees higher than 5 meters and a canopy cover of more than 10 percent, or trees able to reach these thresholds ''in situ''. It does not include land that is predominantly under agricultural or urban use." Using this definition, '' Global Forest Resources Assessment 2020'' found that forests covered , or approximately 31 percent of the world's land area in 2020. Forests are the largest terrestrial ecosystems of Earth by area, and are found around the globe. 45 percent of forest land is in the tropical latitudes. The next largest share of forests are found in subarctic climates, followed by temperate, and subtrop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forest Ecology
Forest ecology is the scientific study of the interrelated patterns, processes, flora, fauna, funga, and ecosystems in forests. The management of forests is known as forestry, silviculture, and forest management. A forest ecosystem is a natural woodland unit consisting of all plants, animals, and micro-organisms (biotic components) in that area functioning together with all of the non-living physical (abiotic) factors of the environment. Importance Forests have an enormously important role to play in the Biosphere, global ecosystem. Forests produce approximately 28% of the Earth's oxygen (the vast majority being created by oceanic plankton), they also serve as homes for millions of people, and billions depend on forests in some way. Likewise, a large proportion of the world's animal species live in forests. Forests are also used for economic purposes such as fuel and wood products. Forest ecology therefore has a great impact upon the whole biosphere and human activities that are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
