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Skeletonema Costatum
''Skeletonema costatum'' is a cosmopolitan centric diatom that belongs to the genus '' Skeletonema''. It was first described by R. K. Greville, who originally named it ''Melosira costata,'' in 1866. It was later renamed by Cleve in 1873 and was more narrowly defined by Zingone et al. and Sarno et al. '' Skeletonema'' ''costatum'' is the most well known species of the genus ''Skeletonema'' and is often one of the dominant species responsible for red tide events. The diatom ''S. costatum'' is known for its carbon acquisition mechanisms, and it has been used in the production of biofuel and as a feed for aquaculture. The organism is appealing for commercial use due to its high photosynthetic efficiency, high tolerance to pH, temperature, and salinity changes, high lipid and fatty acid content, and rapid growth rate. Structure and morphology Cells belonging to ''S. costatum'' are single-celled but exist as long chains of about 6 to 24 cells but can be up to 60 cells in length. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cosmopolitan Distribution
In biogeography, cosmopolitan distribution is the term for the range of a taxon that extends across all or most of the world in appropriate habitats. Such a taxon, usually a species, is said to exhibit cosmopolitanism or cosmopolitism. The extreme opposite of a cosmopolitan species is an endemic one, being found only in a single geographical location. Qualification The caveat “in appropriate habitat” is used to qualify the term "cosmopolitan distribution", excluding in most instances polar regions, extreme altitudes, oceans, deserts, or small, isolated islands. For example, the housefly is highly cosmopolitan, yet is neither oceanic nor polar in its distribution. Related terms and concepts The term pandemism also is in use, but not all authors are consistent in the sense in which they use the term; some speak of pandemism mainly in referring to diseases and pandemics, and some as a term intermediate between endemism and cosmopolitanism, in effect regarding pandemism as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Queensland
North Queensland or the Northern Region is the northern part of the Australian state of Queensland that lies just south of Far North Queensland. Queensland is a massive state, larger than many countries, and its tropical northern part has been historically remote and undeveloped, resulting in a distinctive regional character and identity. Townsville is the largest urban centre in North Queensland, leading it to be regarded as an unofficial capital. The region has a population of 231,628 and covers . Geography There is no official boundary that separates North Queensland from the rest of the state. Unofficially it is usually considered to have a southern border beginning south of the Mackay Region southern boundary, but historically it has been as far south as Rockhampton. To the north is the Far North Queensland region, centred on Cairns and out west is the Gulf Country. A coastal region centred on its largest settlement is the city of Townsville. The city is the locat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photoinhibition
Photoinhibition is light-induced reduction in the photosynthetic capacity of a plant, alga, or cyanobacterium. Photosystem II (PSII) is more sensitive to light than the rest of the photosynthetic machinery, and most researchers define the term as light-induced damage to PSII. In living organisms, photoinhibited PSII centres are continuously repaired via degradation and synthesis of the D1 protein of the photosynthetic reaction center of PSII. Photoinhibition is also used in a wider sense, as dynamic photoinhibition, to describe all reactions that decrease the efficiency of photosynthesis when plants are exposed to light. History The first measurements of photoinhibition were published in 1956 by Bessel Kok. Even in the very first studies, it was obvious that plants have a repair mechanism that continuously repairs photoinhibitory damage. In 1966, Jones and Kok measured the action spectrum of photoinhibition and found that ultraviolet light is highly photoinhibitory. The visible-l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Partial Pressure
In a mixture of gases, each constituent gas has a partial pressure which is the notional pressure of that constituent gas as if it alone occupied the entire volume of the original mixture at the same temperature. The total pressure of an ideal gas mixture is the sum of the partial pressures of the gases in the mixture ( Dalton's Law). The partial pressure of a gas is a measure of thermodynamic activity of the gas's molecules. Gases dissolve, diffuse, and react according to their partial pressures but not according to their concentrations in gas mixtures or liquids. This general property of gases is also true in chemical reactions of gases in biology. For example, the necessary amount of oxygen for human respiration, and the amount that is toxic, is set by the partial pressure of oxygen alone. This is true across a very wide range of different concentrations of oxygen present in various inhaled breathing gases or dissolved in blood; consequently, mixture ratios, like that of breat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Riverine Ecosystem
River ecosystems are flowing waters that drain the landscape, and include the biotic (living) interactions amongst plants, animals and micro-organisms, as well as abiotic (nonliving) physical and chemical interactions of its many parts.Angelier, E. 2003. Ecology of Streams and Rivers. Science Publishers, Inc., Enfield. Pp. 215.”Biology Concepts & Connections Sixth Edition”, Campbell, Neil A. (2009), page 2, 3 and G-9. Retrieved 2010-06-14. River ecosystems are part of larger watershed networks or catchments, where smaller headwater streams drain into mid-size streams, which progressively drain into larger river networks. The major zones in river ecosystems are determined by the river bed's gradient or by the velocity of the current. Faster moving turbulent water typically contains greater concentrations of dissolved oxygen, which supports greater biodiversity than the slow-moving water of pools. These distinctions form the basis for the division of rivers into upland and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estuary
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environments and are an example of an ecotone. Estuaries are subject both to marine influences such as tides, waves, and the influx of saline water, and to fluvial influences such as flows of freshwater and sediment. The mixing of seawater and freshwater provides high levels of nutrients both in the water column and in sediment, making estuaries among the most productive natural habitats in the world. Most existing estuaries formed during the Holocene epoch with the flooding of river-eroded or glacially scoured valleys when the sea level began to rise about 10,000–12,000 years ago. Estuaries are typically classified according to their geomorphological features or to water-circulation patterns. They can have many different names, such as bay ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salinity
Salinity () is the saltiness or amount of salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal to ‰). Salinity is an important factor in determining many aspects of the chemistry of natural waters and of biological processes within it, and is a thermodynamic state variable that, along with temperature and pressure, governs physical characteristics like the density and heat capacity of the water. A contour line of constant salinity is called an ''isohaline'', or sometimes ''isohale''. Definitions Salinity in rivers, lakes, and the ocean is conceptually simple, but technically challenging to define and measure precisely. Conceptually the salinity is the quantity of dissolved salt content of the water. Salts are compounds like sodium chloride, magnesium sulfate, potassium nitrate, and sodium bicarbonate which dissolve into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fujian
Fujian (; alternately romanized as Fukien or Hokkien) is a province on the southeastern coast of China. Fujian is bordered by Zhejiang to the north, Jiangxi to the west, Guangdong to the south, and the Taiwan Strait to the east. Its capital is Fuzhou, while its largest city by population is Quanzhou, both located near the coast of the Taiwan Strait in the east of the province. While its population is predominantly of Chinese ethnicity, it is one of the most culturally and linguistically diverse provinces in China. The dialects of the language group Min Chinese were most commonly spoken within the province, including the Fuzhou dialect of northeastern Fujian and various Hokkien dialects of southeastern Fujian. Hakka Chinese is also spoken, by the Hakka people in Fujian. Min dialects, Hakka and Mandarin Chinese are mutually unintelligible. Due to emigration, a sizable amount of the ethnic Chinese populations of Taiwan, Singapore, Malaysia, Indonesia, and the Philip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sanya
Sanya (; also spelled Samah) is the southernmost city on Hainan Island, and one of the four prefecture-level cities of Hainan Province in South China. According to the 2020 census, the total population of Sanya was 1,031,396 inhabitants, living in an area of . Nevertheless, its built-up (or metro) area encompassing Haitang and Jiyang Districts was home to 801,020 inhabitants as of 2020. The city is renowned for its tropical climate and has emerged as a popular tourist destination, also serving as the training site of the Chinese national beach volleyball team. Sanya is home to small concentrations of Utsul people. Sanya is also the location of Yulin Naval Base, a major military facility on the South China Sea which is home to the People's Liberation Army Navy ballistic nuclear missile fleet. History Known in ancient times as Yazhou, postal romanization: Aichow (), literally "cliff state or prefecture", Sanya's history dates to the Qin Dynasty (221–206 BCE). Due to it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yangtze
The Yangtze or Yangzi ( or ; ) is the longest river in Asia, the third-longest in the world, and the longest in the world to flow entirely within one country. It rises at Jari Hill in the Tanggula Mountains (Tibetan Plateau) and flows in a generally easterly direction to the East China Sea. It is the seventh-largest river by discharge volume in the world. Its drainage basin comprises one-fifth of the land area of China, and is home to nearly one-third of the country's population. The Yangtze has played a major role in the history, culture Culture () is an umbrella term which encompasses the social behavior, institutions, and norms found in human societies, as well as the knowledge, beliefs, arts, laws, customs, capabilities, and habits of the individuals in these grou ..., and economy of China. For thousands of years, the river has been used for water, irrigation, sanitation, transportation, industry, boundary-marking, and war. The prosperous Yangt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytoplankton
Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from the Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'. Phytoplankton obtain their energy through photosynthesis, as do trees and other plants on land. This means phytoplankton must have light from the sun, so they live in the well-lit surface layers ( euphotic zone) of oceans and lakes. In comparison with terrestrial plants, phytoplankton are distributed over a larger surface area, are exposed to less seasonal variation and have markedly faster turnover rates than trees (days versus decades). As a result, phytoplankton respond rapidly on a global scale to climate variations. Phytoplankton form the base of marine and freshwater food webs and are key players in the global carbon cycle. They account for about half of global photosynthetic activity and at least half of the oxygen production, despi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brackish Water
Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root '' brak''. Certain human activities can produce brackish water, in particular civil engineering projects such as dikes and the flooding of coastal marshland to produce brackish water pools for freshwater prawn farming. Brackish water is also the primary waste product of the salinity gradient power process. Because brackish water is hostile to the growth of most terrestrial plant species, without appropriate management it is damaging to the environment (see article on shrimp farms). Technically, brackish water contains between 0.5 and 30 grams of salt per litre—more often expressed as 0.5 to 30 parts per thousand (‰), which is a specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
