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Overstory
In biology, the canopy is the aboveground portion of a plant cropping or crop, formed by the collection of individual 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 animals, etc.). The communities that inhabit the canopy layer are thought to be involved in maintaining forest diversity, 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 mountaineering gear, has made canopy observation significantl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, e.g., including only woody plants with secondary growth, only plants that are usable as lumber, or only plants above a specified height. But wider definitions include taller palms, tree ferns, bananas, and bamboos. Trees are not a monophyletic taxonomic group but consist of a wide variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight. The majority of tree species are angiosperms or hardwoods; of the rest, many are gymnosperms or softwoods. Trees tend to be long-lived, some trees reaching several thousand years old. Trees evolved around 400 million years ago, and it is estimated that there are around three trillion mature trees in the world currently. A tree typically has many secondary branches supported cle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Community
A plant community is a collection or Association (ecology), association of plant species within a designated geographical unit, which forms a relatively uniform patch, distinguishable from neighboring patches of different vegetation types. The components of each plant community are influenced by soil type, topography, climate and human disturbance. In many cases there are several soil types present within a given plant community. This is because the soil type within an area is influenced by two factors, the rate at which water infiltrates or exits (via evapotranspiration) the soil, as well as the rate at which organic matter (any carbon-based compound within the environment, such as decaying plant matter) enters or decays from the soil. Plant communities are studied substantially by ecologists, due to providing information on the effects of dispersal, tolerance to environmental conditions, and response to disturbance of a variety of plant species, information valuable to the comprehe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Understory
In forestry and ecology, understory (American English), or understorey (English in the Commonwealth of Nations, Commonwealth English), also known as underbrush or undergrowth, includes plant life growing beneath the Canopy (biology), forest canopy without penetrating it to any great extent, but above the forest floor. Only a small percentage of light penetrates the canopy, so understory vegetation is generally Shade tolerance, shade-tolerant. The understory typically consists of trees stunted through lack of light, other small trees with low light requirements, saplings, shrubs, vines, and undergrowth. Small trees such as holly and Cornus (genus), dogwood are understory specialists. In Temperate broadleaf and mixed forest, temperate deciduous forests, many understory plants start into growth earlier in the year than the canopy trees, to make use of the greater availability of light at that particular time of year. A gap in the canopy caused by the death of a tree stimulates the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shade Tree
A shade tree is a large tree whose primary role is to provide shade in the surrounding environment due to its spreading canopy and crown, where it may give shelter from sunlight in the heat of the summer for people who seek recreational needs in urban parks and house yards, and thus, also protecting them from the sun's harmful UV rays. Some of the most popular shade trees in temperate countries are oaks, plane trees, willows, birches, beeches, maples, ashes, lindens, and elms. In subtropical countries like Australia and India, figs are popular choices as shade trees. In tropical countries, trees such as some ''Erythrina'' and African tulip tree species are often planted as shade trees. Specialities These trees are commonly grown, and/or used, as shade trees due to their protuberant size: * American elm * American sycamore * Austrian oak * Brush box * Banyan tree * Black walnut * Blue Jacaranda * Camphor laurel * Cape Chestnut * Carob tree * Chinese elm * Coas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trends In Ecology & Evolution
A fad, trend, or craze is any form of collective behavior that develops within a culture, a generation, or social group in which a group of people enthusiastically follow an impulse for a short time period. Fads are objects or behaviors that achieve short-lived popularity but fade away. Fads are often seen as sudden, quick-spreading, and short-lived events. Fads include diets, clothing, hairstyles, toys, and more. Some popular fads throughout history are toys such as yo-yos, hula hoops, and fad dances such as the Macarena, floss and the twist. Similar to habits or customs but less durable, fads often result from an activity or behavior being perceived as popular or exciting within a peer group, or being deemed " cool" as often promoted by social networks.Kornblum (2007), p. 213. A fad is said to "catch on" when the number of people adopting it begins to increase to the point of being noteworthy or going viral. Fads often fade quickly when the perception of novelty i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tropical Rainforest
Tropical rainforests are dense and warm rainforests with high rainfall typically found between 10° north and south of the Equator. They are a subset of the tropical forest biome that occurs roughly within the 28° latitudes (in the torrid zone between the Tropic of Cancer and Tropic of Capricorn). Tropical rainforests are a type of tropical moist broadleaf forest, that includes the more extensive seasonal tropical forests. True rainforests usually occur in tropical rainforest climates where no dry season occurs; all months have an average precipitation of at least . Seasonal tropical forests with tropical monsoon climate, tropical monsoon or tropical savanna climate, savanna climates are sometimes included in the broader definition. Tropical rainforests ecosystems are distinguished by their consistent, high temperatures, exceeding monthly, and substantial annual rainfall. The abundant rainfall results in nutrient-poor, leached soils, which profoundly affect the flora and fau ... [...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] |
Photosynthesis
Photosynthesis ( ) is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their metabolism. ''Photosynthesis'' usually refers to oxygenic photosynthesis, a process that produces oxygen. Photosynthetic organisms store the chemical energy so produced within intracellular organic compounds (compounds containing carbon) like sugars, glycogen, cellulose and starches. To use this stored chemical energy, an organism's cells metabolize the organic compounds through cellular respiration. Photosynthesis plays a critical role in producing and maintaining the oxygen content of the Earth's atmosphere, and it supplies most of the biological energy necessary for complex life on Earth. Some bacteria also perform anoxygenic photosynthesis, which uses bacteriochlorophyll to split hydrogen sulfide as a reductant instead of water, p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mongabay
Mongabay (mongabay.com) is an American conservation news web portal that reports on environmental science, energy, and green design, and features extensive information on tropical rainforests, including pictures and deforestation statistics for countries of the world. It was founded in 1999 by economist Rhett Ayers Butler in order to increase "interest in and appreciation of wildlands and wildlife, while examining the impact of emerging local and global trends in technology, economics, and finance on conservation and development". In recent years, to complement its US-based team, Mongabay has opened bureaus in Indonesia, Latin America, and India, reporting daily in Indonesian, Spanish and English respectively. Mongabay's reporting is available in nine languages. History In an interview with Conjour, Butler said his passion for rainforests drove him to start Mongabay: "I was intrigued by the complexity of these ecosystems and how every species seemed to play a part. As I bec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rainforest
Rainforests are forests characterized by a closed and continuous tree Canopy (biology), canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforests can be generally classified as tropical rainforests or temperate rainforests, but other types have been described. Estimates vary from 40% to 75% of all biotic community, biotic species being Indigenous (ecology), indigenous to the rainforests. There may be many millions of species of plants, insects and microorganisms still undiscovered in tropical rainforests. Tropical rainforests have been called the "jewels of the Earth" and the "medicine chest (idiom), world's largest pharmacy", because over one quarter of natural medicines have been discovered there. Rainforests as well as endemic rainforest species are rapidly disappearing due to #Deforestation, deforestation, the resulting habitat loss and air pollution, pollution of the atmosphere. Definition Rainforests are cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaf Area Index
Leaf area index (LAI) is a dimensionless quantity that characterizes plant Canopy (forest), canopies. It is defined as the one-sided green leaf area per unit ground surface area (''LAI = leaf area / ground area, m2 / m2'') in Broad-leaved tree, broadleaf Canopy (forest), canopies. In conifers, three definitions for LAI have been used: *Half of the total needle surface area per unit ground surface area *Projected (or one-sided, in accordance the definition for broadleaf canopies) needle area per unit ground area *Total needle surface area per unit ground area The definition “half the total leaf area” pertains to biological processes, such as gas exchange, whereas the definition “projected leaf area” was disregarded because the projection of a given area in one direction may differ in another direction when leaves are not flat, thick, or 3D-shaped. Moreover, “ground surface area” is specifically defined as “horizontal ground surface area” to clarify LAI on a sloping ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
