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Species Distribution
Species distribution, or species dispersion, is the manner in which a biological taxon is spatially arranged. The geographic limits of a particular taxon's distribution is its range, often represented as shaded areas on a map. Patterns of distribution change depending on the scale at which they are viewed, from the arrangement of individuals within a small family unit, to patterns within a population, or the distribution of the entire species as a whole (range). Species distribution is not to be confused with biological dispersal, dispersal, which is the movement of individuals away from their center of origin, region of origin or from a population center of high population density, density. Range In biology, the range of a species is the geographical area within which that species can be found. Within that range, distribution is the general structure of the species population, while dispersion is the variation in its population density. Range is often described with the foll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juniperus Communis North American Range Map 1
Junipers are coniferous trees and shrubs in the genus ''Juniperus'' ( ) of the cypress family Cupressaceae. Depending on the taxonomy, between 50 and 67 species of junipers are widely species distribution, distributed throughout the Northern Hemisphere as far south as tropical Africa, including the Arctic, parts of Asia, and Central America. The highest-known juniper forest occurs at an altitude of in southeastern Tibet and the northern Himalayas, creating one of the highest tree lines on earth. Description Junipers vary in size and shape from tall trees, tall, to columnar or low-spreading shrubs with long, trailing branches. They are evergreen with needle-like and/or scale-like leaves. They can be either monoecious or dioecious. The female Conifer cone, seed cones are very distinctive, with fleshy, fruit-like coalescing scales which fuse together to form Juniper berry, a berrylike structure (galbulus), long, with one to 12 unwinged, hard-shelled seeds. In some species, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biotic Component
An ecosystem (or ecological system) is a system formed by organisms in interaction with their environment. The biotic and abiotic components are linked together through nutrient cycles and energy flows. Ecosystems are controlled by external and internal factors. External factors—including climate—control the ecosystem's structure, but are not influenced by it. By contrast, internal factors control and are controlled by ecosystem processes; these include decomposition, the types of species present, root competition, shading, disturbance, and succession. While external factors generally determine which resource inputs an ecosystem has, their availability within the ecosystem is controlled by internal factors. Ecosystems are dynamic, subject to periodic disturbances and always in the process of recovering from past disturbances. The tendency of an ecosystem to remain close to its equilibrium state, is termed its resistance. Its capacity to absorb disturbance and reorga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Appalachian Mountains
The Appalachian Mountains, often called the Appalachians, are a mountain range in eastern to northeastern North America. The term "Appalachian" refers to several different regions associated with the mountain range, and its surrounding terrain. The general definition used is one followed by the United States Geological Survey and the Geological Survey of Canada to describe the respective countries' Physiographic region, physiographic regions. The U.S. uses the term Appalachian Highlands and Canada uses the term Appalachian Uplands; the Appalachian Mountains are not synonymous with the Appalachian Plateau, which is one of the provinces of the Appalachian Highlands. The Appalachian range runs from the Newfoundland (island), Island of Newfoundland in Canada, southwestward to Central Alabama in the United States; south of Newfoundland, it crosses the 96-square-mile (248.6 km2) archipelago of Saint Pierre and Miquelon, an overseas collectivity of France, meaning it is technica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sierra Nevada (U
The Sierra Nevada ( ) is a mountain range in the Western United States, between the Central Valley (California), Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primarily in Nevada. The Sierra Nevada is part of the American Cordillera, an almost continuous chain of mountain ranges that forms the western "backbone" of the Americas. The Sierra runs north-south, and its width ranges from to across east–west. Notable features include the General Sherman Tree, the largest tree in the world by volume; Lake Tahoe, the largest alpine lake in North America; Mount Whitney at , the highest point in the contiguous United States; and Yosemite Valley sculpted by glaciers from one-hundred-million-year-old granite, containing List of waterfalls in Yosemite National Park, high waterfalls. The Sierra is home to three national parks, twenty-six wilderness areas, ten national forests, and two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wildlife Corridor
A wildlife corridor, also known as a habitat corridor, or green corridor, is a designated area habitat (ecology), that connects wildlife populations that have been separated by human activities or structures, such as development, roads, or land clearings. These corridors enable movement of individuals between populations, which helps to prevent negative effects of inbreeding and reduced genetic diversity, often caused by genetic drift, that can occur in isolated populations. Additionally, corridors support the re-establishment of populations that may have been reduced or wiped out due to Stochastic process, random events like fires or disease. They can also mitigate some of the severe impacts of habitat fragmentation, a result of urbanization that divides habitat areas and restricts animal movement. Habitat fragmentation from human development poses an increasing threat to biodiversity, and habitat corridors help to reduce its harmful effects. Corridors aside from their benefit t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tanker (ship)
A tanker (or tank ship or tankship) is a ship designed to transport or store liquids or gases in Bulk liquids, bulk. Major types of tanker ship include the oil tanker (or petroleum tanker), the chemical tanker, Cargo ship, cargo ships, and a gas carrier. Tankers also carry commodities such as vegetable oils, molasses and wine. In the United States Navy and Military Sealift Command, a tanker used to refuel other ships is called an oiler (ship), oiler (or replenishment oiler if it can also supply dry stores) but many other navies use the terms tanker and replenishment tanker. Tankers were first developed in the late 19th century as iron and steel hulls and pumping systems were developed. As of 2005, there were just over 4,000 tankers and supertankers or greater operating worldwide. Description Tankers can range in size of capacity from several hundred tonnage, tons, which includes vessels for servicing small harbours and coastal settlements, to several hundred thousand tons, f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transportation
Transport (in British English) or transportation (in American English) is the intentional Motion, movement of humans, animals, and cargo, goods from one location to another. Mode of transport, Modes of transport include aviation, air, land transport, land (rail transport, rail and road transport, road), ship transport, water, cable transport, cable, pipeline transport, pipelines, and space transport, space. The field can be divided into infrastructure, vehicles, and operations. Transport enables human trade, which is essential for the development of civilizations. Transport infrastructure consists of both fixed installations, including roads, railways, airway (aviation), airways, waterways, canals, and pipeline transport, pipelines, and terminals such as airports, train station, railway stations, bus stations, warehouses, trucking terminals, refueling depots (including fuel docks and fuel stations), and seaports. Terminals may be used both for the interchange of passengers and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Globalization
Globalization is the process of increasing interdependence and integration among the economies, markets, societies, and cultures of different countries worldwide. This is made possible by the reduction of barriers to international trade, the liberalization of capital movements, the development of transportation, and the advancement of information and communication technologies. The term ''globalization'' first appeared in the early 20th century (supplanting an earlier French term ''mondialisation''). It developed its current meaning sometime in the second half of the 20th century, and came into popular use in the 1990s to describe the unprecedented international connectivity of the Post–Cold War era, post–Cold War world. The origins of globalization can be traced back to the 18th and 19th centuries, driven by advances in transportation and communication technologies. These developments increased global interactions, fostering the growth of international trade and the exc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Impact On The Environment
Human impact on the environment (or anthropogenic environmental impact) refers to changes to biophysical environments and to ecosystems, biodiversity, and natural resources caused directly or indirectly by humans. Modifying the environment to fit the needs of society (as in the built environment) is causing severe effects including global warming, environmental degradation (such as ocean acidification), mass extinction and biodiversity loss, ecological crisis, and ecological collapse. Some human activities that cause damage (either directly or indirectly) to the environment on a global scale include population growth, neoliberal economic policies and rapid economic growth, overconsumption, overexploitation, pollution, and deforestation. Some of the problems, including global warming and biodiversity loss, have been proposed as representing catastrophic risks to the survival of the human species. The term ''anthropogenic'' designates an effect or object resulting from h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Dispersal
Biological dispersal refers to both the movement of individuals (animals, plants, fungi, bacteria, etc.) from their birth site to their breeding site ('natal dispersal') and the movement from one breeding site to another ('breeding dispersal'). Dispersal is also used to describe the movement of propagules such as seeds and spores. Technically, dispersal is defined as any movement that has the potential to lead to gene flow. The act of dispersal involves three phases: departure, transfer, and settlement. There are different fitness costs and benefits associated with each of these phases. Through simply moving from one habitat Landscape ecology#Patch and mosaic, patch to another, the dispersal of an individual has consequences not only for individual fitness (biology), fitness, but also for population dynamics, population genetics, and species distribution. Understanding dispersal and the consequences, both for evolutionary strategies at a species level and for processes at an e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exploration
Exploration is the process of exploring, an activity which has some Expectation (epistemic), expectation of Discovery (observation), discovery. Organised exploration is largely a human activity, but exploratory activity is common to most organisms capable of directed Animal locomotion, locomotion and the ability to learn, and has been described in, amongst others, social insects foraging behaviour, where feedback from returning individuals affects the activity of other members of the group. Types Geographical Geographical exploration, sometimes considered the default meaning for the more general term exploration, is the practice of discovering lands and regions of the planet Earth remote or relatively inaccessible from the origin of the explorer. The surface of the Earth not covered by water has been relatively comprehensively explored, as access is generally relatively straightforward, but underwater and subterranean areas are far less known, and even at the surface, much is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenology
Phenology is the study of periodic events in biological life cycles and how these are influenced by seasonal and interannual variations in climate, as well as habitat factors (such as elevation). Examples include the date of emergence of leaves and flowers, the first flight of butterflies, the first appearance of migratory birds, the date of leaf colouring and fall in deciduous trees, the dates of egg-laying of birds and amphibia, or the timing of the developmental cycles of temperate-zone honey bee colonies. In the scientific literature on ecology, the term is used more generally to indicate the time frame for any seasonal biological phenomena, including the dates of last appearance (e.g., the seasonal phenology of a species may be from April through September). Because many such phenomena are very sensitive to small variations in climate, especially to temperature, phenological records can be a useful proxy for temperature in historical climatology, especially in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
