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Howellia
''Howellia aquatilis'', the water howellia, is a small plant in the family Campanulaceae and was considered a threatened species between 1994 and 2019. It is the only species in the monotypic genus ''Howellia''. Thomas Jefferson Howell (botanist), Thomas Jefferson Howell and Joseph Howell discovered the species in 1878. Distribution The water howellia is found in large area of the Pacific Northwest region of the United States. It can be found in California, Idaho, Montana, and Washington (state), Washington, and it is known historically from Oregon. The plant grows in wetland habitat surrounded by forests, which provide organic material. Associated tree species include ''Populus trichocarpa'' (California poplar), ''Populus tremuloides, P. tremuloides'' (quaking aspen), and ''Fraxinus latifolia'' (Oregon ash). The water bodies are located in glacial potholes, Meander, river oxbows, ephemeral ponds, flood plains and other areas that fill with water periodically as snow melts and sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Campanulaceae
The family Campanulaceae (also bellflower family), of the order Asterales, contains nearly 2400 species in 84 genera of herbaceous plants, shrubs, and rarely small trees, often with milky sap. Among them are several familiar garden plants belonging to the genera '' Campanula'' (bellflower), ''Lobelia'', and ''Platycodon'' (balloonflower). ''Campanula rapunculus'' (rampion or r. bellflower) and ''Codonopsis lanceolata'' are eaten as vegetables. ''Lobelia inflata'' (indian tobacco), '' L. siphilitica'' and '' L. tupa'' (devil's tobacco) and others have been used as medicinal plants. ''Campanula rapunculoides'' (creeping bellflower) may be a troublesome weed, particularly in gardens, while ''Legousia'' spp. may occur in arable fields. Most current classifications include the segregate family Lobeliaceae in Campanulaceae as subfamily Lobelioideae. A third subfamily, Cyphioideae, includes the genus ''Cyphia'', and sometimes also the genera ''Cyphocarpus'', ''Nemacladus'', ''Parishell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lobelioideae
Lobelioideae is a subfamily of the plant family Campanulaceae. It contains 32 genera, totalling about 1200 species. Some of the larger genera are ''Lobelia'', ''Siphocampylus'', ''Centropogon'', ''Burmeistera'' and '' Cyanea''. They are perennials, sometimes annuals, ranging in form from herbs to small trees. Most species are tropical in distribution, but in total this subfamily occurs almost worldwide, being absent only from Arctic regions, central Asia and the Near East. The subfamily is particularly diverse in Hawaii, where well over 100 species of Hawaiian lobelioids have radiated from a single introduction. This subfamily was formerly given family rank as Lobeliaceae, under a somewhat different circumscription. The leaves are simple and alternate. The plants have milky sap. The flowers are bilaterally symmetric with five lobes and stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Jefferson Howell (botanist)
Thomas Jefferson Howell (October 8, 1842 – December 3, 1912) was an American botanist.Makers of American Botany, Harry Baker Humphrey, Ronald Press Company, Library of Congress Card Number 61-18435 Howell is considered one of the top three self-taught botanists of his era for the Pacific Northwest; the other two being Wilhelm Nikolaus Suksdorf and William Conklin Cusick. Personal life Howell was born in Cooper County, Missouri on October 8, 1842.Ornduff, Robert"Thomas Jefferson Howell and the First Pacific Northwest Flora" ''Kalmiopsis'' (Volume 15), Native Plant Society of Oregon, University of Oregon, Eugene, Oregon, pp. 32–41, 2008. He came west with his parents, Benjamin and Elizabeth (Mathews) Howell, and his four siblings in 1850. The Howells took up a Donation Land Claim on Sauvie Island in 1854. Howell was largely self-taught, and only had six months of formal schooling. His father was a doctor who had taught him some Latin and science, but he mostly educated h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meander
A meander is one of a series of regular sinuous curves in the channel of a river or other watercourse. It is produced as a watercourse erodes the sediments of an outer, concave bank ( cut bank) and deposits sediments on an inner, convex bank which is typically a point bar. The result of this coupled erosion and sedimentation is the formation of a sinuous course as the channel migrates back and forth across the axis of a floodplain. The zone within which a meandering stream periodically shifts its channel is known as a meander belt. It typically ranges from 15 to 18 times the width of the channel. Over time, meanders migrate downstream, sometimes in such a short time as to create civil engineering challenges for local municipalities attempting to maintain stable roads and bridges.Neuendorf, K.K.E., J.P. Mehl Jr., and J.A. Jackson, J.A., eds. (2005) ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. Charlton, R., 2007. ''Fundamentals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Introduced Species
An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there by human activity, directly or indirectly, and either deliberately or accidentally. Non-native species can have various effects on the local ecosystem. Introduced species that become established and spread beyond the place of introduction are considered naturalized. The process of human-caused introduction is distinguished from biological colonization, in which species spread to new areas through "natural" (non-human) means such as storms and rafting. The Latin expression neobiota captures the characteristic that these species are ''new'' biota to their environment in terms of established biological network (e.g. food web) relationships. Neobiota can further be divided into neozoa (also: neozoons, sing. neozoon, i.e. animals) and neophyt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Livestock
Livestock are the domesticated animals raised in an agricultural setting to provide labor and produce diversified products for consumption such as meat, eggs, milk, fur, leather, and wool. The term is sometimes used to refer solely to animals who are raised for consumption, and sometimes used to refer solely to farmed ruminants, such as cattle, sheep, goats and pigs. Horses are considered livestock in the United States. The USDA classifies pork, veal, beef, and lamb (mutton) as livestock, and all livestock as red meat. Poultry and fish are not included in the category. The breeding, maintenance, slaughter and general subjugation of livestock, called '' animal husbandry'', is a part of modern agriculture and has been practiced in many cultures since humanity's transition to farming from hunter-gatherer lifestyles. Animal husbandry practices have varied widely across cultures and time periods. It continues to play a major economic and cultural role in numerous communities. Lives ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silt
Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension with water. Silt usually has a floury feel when dry, and lacks plasticity when wet. Silt also can be felt by the tongue as granular when placed on the front teeth (even when mixed with clay particles). Silt is a common material, making up 45% of average modern mud. It is found in many river deltas and as wind-deposited accumulations, particularly in central Asia, north China, and North America. It is produced in both very hot climates (through such processes as collisions of quartz grains in dust storms) and very cold climates (through such processes as glacial grinding of quartz grains.) Loess is soil rich in silt which makes up some of the most fertile agricultural land on Earth. However, silt is very vulnerable to erosion, and it has poor mechanical properties, making construction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyke (construction)
A levee (), dike (American English), dyke (Commonwealth English), embankment, floodbank, or stop bank is a structure that is usually earthen and that often runs parallel to the course of a river in its floodplain or along low-lying coastlines. The purpose of a levee is to keep the course of rivers from changing and to protect against flooding of the area adjoining the river or coast. Levees can be naturally occurring ridge structures that form next to the bank of a river, or be an artificially constructed fill or wall that regulates water levels. Ancient civilizations in the Indus Valley, ancient Egypt, Mesopotamia and China all built levees. Today, levees can be found around the world, and failures of levees due to erosion or other causes can be major disasters. Etymology Speakers of American English (notably in the Midwest and Deep South) use the word ''levee'', from the French word (from the feminine past participle of the French verb , 'to raise'). It originated i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrology
Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and environmental watershed sustainability. A practitioner of hydrology is called a hydrologist. Hydrologists are scientists studying earth or environmental science, civil or environmental engineering, and physical geography. Using various analytical methods and scientific techniques, they collect and analyze data to help solve water related problems such as environmental preservation, natural disasters, and water management. Hydrology subdivides into surface water hydrology, groundwater hydrology (hydrogeology), and marine hydrology. Domains of hydrology include hydrometeorology, surface hydrology, hydrogeology, drainage-basin management, and water quality, where water plays the central role. Oceanography and meteorology are not included because water is only one of many important aspects within those fields. H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Logging
Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidding, on-site processing, and loading of trees or logs onto trucks or skeleton cars. Logging is the beginning of a supply chain that provides raw material for many products societies worldwide use for housing, construction, energy, and consumer paper products. Logging systems are also used to manage forests, reduce the risk of wildfires, and restore ecosystem functions, though their efficiency for these purposes has been challenged. In forestry, the term logging is sometimes used narrowly to describe the logistics of moving wood from the stump to somewhere outside the forest, usually a sawmill or a lumber yard. In common usage, however, the term may cover a range of forestry or silviculture activities. Illegal logging refers to the harvesting, transportation, purchase, or sale of timber in violation of laws. The harvesting procedure itself may be illegal, includin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germination
Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, ferns, bacteria, and the growth of the pollen tube from the pollen grain of a seed plant. Seed plants Germination is usually the growth of a plant contained within a seed; it results in the formation of the seedling. It is also the process of reactivation of metabolic machinery of the seed resulting in the emergence of radicle and plumule. The seed of a vascular plant is a small package produced in a fruit or cone after the union of male and female reproductive cells. All fully developed seeds contain an embryo and, in most plant species some store of food reserves, wrapped in a seed coat. Some plants produce varying numbers of seeds that lack embryos; these are empty seeds which never germinate. Dormant seeds are viable seeds that do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Diversity
Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species, it ranges widely from the number of species to differences within species and can be attributed to the span of survival for a species. It is distinguished from ''genetic variability'', which describes the tendency of genetic characteristics to vary. Genetic diversity serves as a way for populations to adapt to changing environments. With more variation, it is more likely that some individuals in a population will possess variations of alleles that are suited for the environment. Those individuals are more likely to survive to produce offspring bearing that allele. The population will continue for more generations because of the success of these individuals. The academic field of population genetics includes several hypotheses and theories regarding genetic diversity. The neutral theory of evolution proposes that diversity is the result of the accumulation of neutral substitutions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
