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Biomanipulation
Biomanipulation is the deliberate alteration of an ecosystem by adding or removing species, especially predators. Aquatic ecosystems Changing the fish population of bodies of water as a part of watershed management can facilitate desirable changes in aquatic ecosystems suffering from eutrophication characterized by domination by phytoplankton aiding ecosystem restoration, an application of restoration ecology. In ponds or lakes alternative stable conditions, one with high algae populations, little other plant life, and turbid water, another with low algae populations, a diverse plant population, and clear water, may exist. In addition to prevention of excess nutrients such as phosphorus and nitrates, removal of certain fish species adapted to turbid water may facilitate change from one steady state to the other, an application of dynamical systems theory. Fish species may be removed by means of poison, harvesting, or introduction of predatory species. As a different fish community wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Watershed Management
Watershed management is the study of the relevant characteristics of a watershed aimed at the sustainable distribution of its resources and the process of creating and implementing plans, programs and projects to sustain and enhance watershed functions that affect the plant, animal, and human communities within the watershed boundary. Features of a watershed that agencies seek to manage to include water supply, water quality, drainage, stormwater runoff, water rights and the overall planning and utilization of watersheds. Landowners, land use agencies, stormwater management experts, environmental specialists, water use surveyors and communities all play an integral part in watershed management. Controlling pollution In agricultural systems, common practices include the use of buffer strips, grassed waterways, the re-establishment of wetlands, and forms of sustainable agriculture practices such as conservation tillage, crop rotation and inter-cropping. After certain practices a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecosystem
An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the system through photosynthesis and is incorporated into plant tissue. By feeding on plants and on one another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and microbes. Ecosystems are controlled by external and internal factors. External factors such as climate, parent material which forms the soil and topography, control the overall structure of an ecosystem but are not themselves influenced by the ecosystem. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broads Authority
The Broads Authority is the agency which has statutory responsibility for the Broads in England. Originally, the Nature Conservancy Council (now Natural England), pressed for a special authority to manage the Broads which had been neglected for a long time. In 1978, the forerunner to the present-day Broads Authority was established by the Countryside Commission (now also Natural England). Ten years later, it had become clear that a statutory body was needed, and a special Act of Parliament, the Norfolk and Suffolk Broads Act 1988 (referred to as ''the Broads Act'') made the Broads Authority into a special statutory authority which gave it parity yet establishing key differences with national park authorities. Responsibilities The Broads Authority has to: *conserve and enhance the natural beauty, wildlife and cultural heritage of the Broads *promote opportunities for the understanding and enjoyment of the special qualities of the Broads by the public *protect the interests of navig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algal Bloom
An algal bloom or algae bloom is a rapid increase or accumulation in the population of algae in freshwater or marine water systems. It is often recognized by the discoloration in the water from the algae's pigments. The term ''algae'' encompasses many types of aquatic photosynthetic organisms, both macroscopic multicellular organisms like seaweed and microscopic unicellular organisms like cyanobacteria. ''Algal bloom'' commonly refers to the rapid growth of microscopic unicellular algae, not macroscopic algae. An example of a macroscopic algal bloom is a kelp forest. Algal blooms are the result of a nutrient, like nitrogen or phosphorus from various sources (for example fertilizer runoff or other forms of nutrient pollution), entering the aquatic system and causing excessive growth of algae. An algal bloom affects the whole ecosystem. Consequences range from the benign feeding of higher trophic levels to more harmful effects like blocking sunlight from reaching other organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zooplankton
Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by currents in the ocean, or by currents in seas, lakes or rivers. Zooplankton can be contrasted with phytoplankton, which are the plant component of the plankton community ("phyto" comes from the Greek word for ''plant''). Zooplankton are heterotrophic (other-feeding), whereas phytoplankton are autotrophic (self-feeding). This means zooplankton cannot manufacture their own food but must eat other plants or animals instead — in particular they eat phytoplankton. Zooplankton are generally larger than phytoplankton, most are microscopic, but some (such as jellyfish) are macroscopic and can be seen with the naked eye. Many protozoans (single-celled protists that prey on other microscopic life) are zooplankton, including zooflagellates, fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swimmer's Itch
Swimmer's itch, cercarial dermatitis or schistosome dermatitis is a short-term allergic contact dermatitis occurring in the skin of humans that have been infected by water-borne schistosomes, a type of flatworm. It is common in freshwater, brackish and marine habitats worldwide. The incidence of this condition may be increasing, although this may be attributed to better monitoring and reporting. Nevertheless, the condition is considered to be an emerging infectious disease. The main symptom is itchy papules (raised skin) that commonly occur within 2 days of infection. Initially, wheals develop quickly, then turn into maculae in about half an hour. Within 10–12 hours these turn into very itchy papules that reach their worst by the second or third day. The papules disappear in 1–2 weeks but secondary effects from scratching can continue longer. The intense itching, which peaks after 48–72 hours, is associated with pain and swelling of the affected areas. People repeatedly expo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trichobilharzia Ocellata
''Trichobilharzia'' is a genus of trematodes in the family Schistosomatidae. They are worldwide distributed parasites of anatid birds and causative agents of human cercarial dermatitis. Species *'' Trichobilharzia ocellata'' (La Valette, 1855)La Valette-St. George, Adolf Johann Hubert Freiherr von (1855). ''Symbolae ad Trematodum Evolutions Historiam. Dissertatio Inauguralis quam Consensu et Auctoritate Amplissimi Philosophorum Ordinis in Alma Litterarum Universitate Friderica Guilelma pro Summis in Philosophia Honoribus Rite Capessendis die XIV. M. Aprilis A. MDCCCLV''. Berolini: Typis Ernesti Kuehn. *''Trichobilharzia regenti ''Trichobilharzia regenti'' is a neuropathogenic parasitic flatworm of birds which also causes cercarial dermatitis in humans. The species was originally described in 1998 in the Czech Republic and afterwards it was detected also in other Europe ...'' Horák, Kolářová & Dvořák, 1998 * '' Trichobilharzia franki'' Müller & Kimmig, 1994 Müller V, K ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radix Peregra
''Peregriana peregra'' is a species of air-breathing freshwater snail, an aquatic pulmonate gastropod in the family Lymnaeidae, the pond snails. Distribution and habitat This small pond snail is found in Europe, Newfoundland and northern Asia. This species is common in slow-moving or still water.Janus Horst. (1965). ''The young specialist looks at land and freshwater molluscs''. Burke, London. References External links''Radix peregra'' at Animalbase AnimalBase is a project brought to life in 2004 and is maintained by the University of Göttingen, Germany. The goal of the AnimalBase project is to digitize early zoological literature, provide copyright-free open access to zoological works, and pr ... Lymnaeidae Gastropods described in 1774 Taxa named by Otto Friedrich Müller {{Lymnaeidae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snail
A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gastropoda that have a coiled shell that is large enough for the animal to retract completely into. When the word "snail" is used in this most general sense, it includes not just land snails but also numerous species of sea snails and freshwater snails. Gastropods that naturally lack a shell, or have only an internal shell, are mostly called '' slugs'', and land snails that have only a very small shell (that they cannot retract into) are often called ''semi-slugs''. Snails have considerable human relevance, including as food items, as pests, and as vectors of disease, and their shells are used as decorative objects and are incorporated into jewelry. The snail has also had some cultural significance, tending to be associated with lethargy. The sn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyprinidae
Cyprinidae is a family of freshwater fish commonly called the carp or minnow family. It includes the carps, the true minnows, and relatives like the barbs and barbels. Cyprinidae is the largest and most diverse fish family and the largest vertebrate animal family in general with about 3,000 species, of which only 1,270 remain extant, divided into about 370 genera. Cyprinids range from about 12 mm in size to the giant barb (''Catlocarpio siamensis''). By genus and species count, the family makes up more than two-thirds of the ostariophysian order Cypriniformes. The family name is derived from the Greek word ( 'carp'). Biology and ecology Cyprinids are stomachless fish with toothless jaws. Even so, food can be effectively chewed by the gill rakers of the specialized last gill bow. These pharyngeal teeth allow the fish to make chewing motions against a chewing plate formed by a bony process of the skull. The pharyngeal teeth are unique to each species and are used by scient ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chara (alga)
''Chara'' is a genus of charophyte green algae in the family Characeae. They are multicellular and superficially resemble land plants because of stem-like and leaf-like structures. They are found in freshwater, particularly in limestone areas throughout the northern temperate zone, where they grow submerged, attached to the muddy bottom. They prefer less oxygenated and hard water and are not found in waters where mosquito larvae are present. They are covered with calcium carbonate deposits and are commonly known as stoneworts. Cyanobacteria have been found growing as epiphytes on the surfaces of ''Chara'', where they may be involved in fixing nitrogen, which is important to plant nutrition. Structure The branching system of ''Chara'' species is complex with branches derived from apical cells which cut off segments at the base to form nodal and internodal cells alternately.Round, F.E. 1965.''The Biology of the algae.'' Ernest Arnold. The main axes bear whorls of branches in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
