E8. Pianka, E. R. 1966. Latitudinalgradients in speciesdiversity a review of concepts. American ... Society of London Series B, 274 165 174. Rohde, K. 1992. Latitudinalgradients in speciesdiversity ... does not explain latitudinalgradients in speciesdiversity. Oikos, 79, 169 172. Romdal, T. S., R ... . On this view, if latitudinalgradients of species richness were determined solely by MDE, observed ... is not a valid explanation for the latitudinalspeciesdiversity gradient Rohde 1997, Hawkins ... cause of the latitudinaldiversity gradient as they fail to explain why species interactions ..., and B. Beckage. 2002. Density dependent mortality and the latitudinal gradient in speciesdiversity ... on the latitudinal mid domain effect. Ecology 86 235 244. Rosenzweig, M. L. 1992. Speciesdiversity ... model of latitudinalgradients of species richness with an empirical test for marsupials ... latitudinalgradients in speciesLatitudinalgradients in species a Knol by Klaus Rohde , Professor ... to as the latitudinaldiversity gradient LDG , is one of the most widely recognized patterns ... ref Explaining the latitudinaldiversity gradient is one of the great contemporary challenges ... What determines patterns of speciesdiversity? was among the 25 key research themes for the future ... 2005 , and suggested the hypothesis that MDE might contribute to the latitudinal gradient in species ... gradients of species richness, particularly for wide ranging species e.g. Jetz and Rahbek 2001, Koleff ... of removing tropical species on latitudinal patterns in avian species richness in the New World and found ... climate related hypothesis is the climate harshness hypothesis, which states the latitudinaldiversity ... harshness hypothesis, climate stability is suggested to be the reason for the latitudinaldiversity ... in more detail below suggests that temperate regions are thus expected to have less speciesdiversity ... to the assumption that climate stability means higher speciesdiversity. For example, low species ... more details
diversity Gamma diversity Abundance ecology Relative species abundance Species area curve Latitudinalgradients in speciesdiversity Biodiversity Genetic diversity External links cite web url http ...Speciesdiversity is the effective number of different species that are represented in a collection of individuals ... of interest where all species may not be equally abundant . Speciesdiversity consists of two components .... 2010. A consistent terminology for quantifying speciesdiversity? Yes, it does exist. Oecologia 4 853 860. doi 10.1007 s00442 010 1812 0 ref Calculation of diversitySpeciesdiversity in a dataset ... proportional abundance. Consequently, large values of q lead to smaller speciesdiversity than small ... the value of q has no effect, but speciesdiversity at any value of q equals species richness. Negative values of q are not used, because then the effective number of speciesdiversity would exceed the actual ... the diversity in relation to any classification, not only species. If the individuals are classified ... indices to quantify speciesdiversity. Such indices include species richness , the Shannon index ... diversity, the dataset used for the calculations can be obtained in different ways. Although speciesdiversity can be calculated for any dataset where individuals have been identified to species, meaningful .... In practice, the interest is usually in the speciesdiversity of areas so large that not all individuals ..., because the speciesdiversity of the available sample generally gives an underestimation of the speciesdiversity in the entire population. Applying different Sample statistics sampling ... introduce a species that was not yet represented. How much this increases speciesdiversity depends on the value of q when q 0, each new actual species causes speciesdiversity to increase by one ... speciesdiversity. ref Tuomisto, H. 2010 A diversity of beta diversities straightening up a concept ... speciesdiversity than sets with fewer individuals. When speciesdiversity values are compared among ... more details
wiktionary diversity wikiquote Science and technology Biodiversity , the degree of variation of life forms within a given ecosystem, biome, or an entire planet. Diversity Index , a statistic intended to assess the diversity of any population in which each member belongs to a unique group, type or species. Diversity scheme , a method for improving the reliability of a message signal by using multiple communications channels. Antenna diversity , a method of wireless communication that use two or more antennas to improve the quality and reliability of the link. Sociology, economics, law, and politics Multiculturalism , or ethnic diversity, the promotion of multiple ethnic cultures Cultural diversity , the respect of difference cultures and interculturality Diversity business , the business tactic which encourages diversity to better serve a heterogeneous customer base Diversity politics , the political and social policy of encouraging tolerance for people of different backgrounds Diversity jurisdiction , a concept under which U.S. federal courts can hear suits between parties from different states Diversification finance involves spreading investments Diversification marketing strategy is a corporate strategy to decrease market penetration Team composition Other Diversity dance troupe , an English dance troupe who won the third series of Britain s Got Talent Diversity training , the process of educating employees, students or volunteers to function in a diverse environment disambiguation ar bg da Diversitet de Diversit t it Diversit nl Diversiteit ja pt Diversidade tr e itlilik ... more details
small areas. Many organism groups have most species in the tropics, which leads to Latitudinalgradients in speciesdiversitylatitudinalgradients in species richness . There has been much discussion ... richness is similar, but all the species are common and widespread. See also SpeciesdiversitySpecies evenness Abundance ecology Relative species abundance Species area curve Latitudinalgradients in speciesdiversity Rapoport s rule Scaling pattern of occupancy Storage effect References reflist ...Species richness is the number of different species represented in a set or collection of individuals. Species richness is simply a count of species, and it does not take into account the Abundance ecology abundances of the species or their Relative species abundance relative abundance distributions . In contrast, speciesdiversity takes into account both species richness and species evenness . Sampling considerations Depending on the purposes of quantifying species richness, the individuals can ... been defined, its species richness can be exactly quantified, provided the species level taxonomy of the organisms of interest is well enough known. Applying different Speciesspecies delimitations will lead to different species richness values for the same set of individuals. In practice, people are usually interested in the species richness of areas so large that not all individuals in them can be observed and identified to species. Then applying different Sample statistics sampling methods will lead to different sets of individuals being observed for the same area of interest, and the species ... a species that was not yet represented in the set, and thereby increase the species richness of the set. For this reason, sets with many individuals can be expected to contain more species than sets with fewer individuals. If species richness of the obtained sample is taken to represent species richness ..., 345, 101 118. ref Properties of the sample, especially the number of species only represented ... more details
FeatureDetectionCompVisNavbox Histogram of Oriented Gradients HOG are feature descriptors used in computer vision and image processing for the purpose of object detection . The technique counts occurrences of gradient orientation in localized portions of an image. This method is similar to that of edge orientation histogram s, scale invariant feature transform descriptors, and shape context s, but differs in that it is computed on a dense grid of uniformly spaced cells and uses overlapping local contrast normalization for improved accuracy. Navneet Dalal and Bill Triggs , researchers for the French National Institute for Research in Computer Science and Control INRIA , first described Histogram of Oriented Gradient descriptors in their June 2005 paper to the Conference on Computer Vision and Pattern Recognition CVPR . In this work they focused their algorithm on the problem of pedestrian ... and shape within an image can be described by the distribution of intensity gradients or edge ... aceMedia files document wp7 2005 cvpr05 inria.pdf title Histograms of Oriented Gradients ... aceMedia files document wp7 2005 cvpr05 inria.pdf title Histograms of Oriented Gradients ... found that unsigned gradients used in conjunction with 9 histogram channels performed best in their human ... aceMedia files document wp7 2005 cvpr05 inria.pdf title Histograms of Oriented Gradients ... files document wp7 2005 cvpr05 inria.pdf title Histograms of Oriented Gradients for Human Detection ... of Oriented Gradients for Human Detection, pg. 6 ref SVM classifier The final step in object recognition ... 2005 cvpr05 inria.pdf title Histograms of Oriented Gradients for Human Detection, pg. 4 ref Deleted ... slides dalal.pdf title Object Detection using Histograms of Oriented Gradients ref Deleted image ... Detection using Infrared images and Histograms of Oriented Gradients ref At the IEEE Conference ... of Histograms of Oriented Gradients ref See also Corner detection Pedestrian detection Feature computer ... more details
, it needs to be taken into account that the speciesdiversity in the dataset generally gives an underestimation of the speciesdiversity in a larger area. The smaller the available sample in relation ... of underestimation can be estimated from a species area curve . Different gamma diversity concepts Researchers have used different ways to define speciesdiversitydiversity , which in practice ... by one or more Diversity index diversity indices , such as species richness , the Shannon index or the Simpson .... 2002 The additive partitioning of speciesdiversity recent revival of an old idea. Oikos, 99, 3 9 ... measure of speciesdiversity. This measure allows weighting rare and abundant species in different ... all species may not be equally abundant . ref name Tuomisto2010a ref Hill, M. O. 1973 Diversity ..., H. 2010. A consistent terminology for quantifying speciesdiversity? Yes, it does exist. Oecologia ... terminology for speciesdiversity? Yes, if we choose to use it. Oecologia, 167, 903 911. ref Calculating gamma diversity Suppose speciesdiversity is equated with the effective number of species in a dataset. Then gamma diversity can be calculated by first taking the weighted mean of species proportional ... abundance of the i th species is math p i math . Large values of q lead to smaller gamma diversity ...The term gamma diversitydiversity was introduced by R. H. Whittaker ref name Whittaker1960 Whittaker ..., 279 338. ref together with the terms alpha diversitydiversity and beta diversitydiversity . Whittaker s idea was that the total speciesdiversity in a landscape is determined by two different things, the mean speciesdiversity in sites or habitats at a more local scale and the differentiation among those habitats . According to this reasoning, alpha diversity and beta diversity constitute independent components of gamma diversity math gamma alpha times beta math Scale considerations ... has been reached on what spatial scales are appropriate to quantify gamma diversity. ref Whittaker ... more details
and gamma diversitydiversity . Whittaker s idea was that the total speciesdiversity in a landscape gamma diversity is determined by two different things, the mean speciesdiversity in sites .... et al. 2001 . Scale and species richness towards a general, hierarchical theory of speciesdiversity ... to be taken into account that the speciesdiversity in the subunits generally gives an underestimation of the speciesdiversity in larger areas. ref Colwell, R. K. and Coddington, J. A. 1994 Estimating ... different definitions of alpha diversity. Whittaker himself used the term both for the speciesdiversity in a single subunit and for the mean speciesdiversity in a collection of subunits. ref ... speciesdiversity consists of alpha and beta components. ref name Tuomisto2011 Tuomisto, H. 2011 Commentary do we have a consistent terminology for speciesdiversity? Yes, if we choose to use it. Oecologia, 167, 903 911. ref Definitions of alpha diversity can also differ in what they assume species ... diversity indices , such as species richness, the Shannon index or the Simpson index. ref name Whittaker1960 ref Lande, R. 1996 Statistics and partitioning of speciesdiversity, and similarity among multiple ... be better to use the effective number of species as the universal measure of speciesdiversity. This measure allows weighting rare and abundant species in different ways, just as the diversity ... terminology for quantifying speciesdiversity? Yes, it does exist. Oecologia 4 853 860. doi 10.1007 s00442 010 1812 0 ref Calculating alpha diversity Suppose speciesdiversity is equated with the effective number of species, and alpha diversity with the mean speciesdiversity per subunit ..., and then take the inverse of this mean. The second approach is to calculate the speciesdiversity ... values, each of which represents the effective species density speciesdiversity per subunit in one ... with the highest proportional abundance and to those subunits with the lowest speciesdiversity ... more details
was that the total speciesdiversity in a landscape is determined by two different things, the mean speciesdiversity at the habitat level and the differentiation among habitats . Whittaker ..., R. 2011 Commentary Do we have a consistent terminology for speciesdiversity? The fallacy of true ... speciesdiversity? Yes, it does exist. Oecologia 4 853 860. doi 10.1007 s00442 010 1812 0 ref ref Jurasinski, G. and Koch, M. 2011 Commentary do we have a consistent terminology for speciesdiversity .... E and Rodr guez, P. 2011 Commentary Do we have a consistent terminology for speciesdiversity? Back ... ref Tuomisto, H. 2011 Commentary do we have a consistent terminology for speciesdiversity? Yes, if we ... and alpha diversity can be calculated directly from species inventory data. ref name Tuomisto2010a ... s original definitions of beta diversity is Here gamma diversity is the total speciesdiversity of a landscape, and alpha diversity is the mean speciesdiversity per habitat. Because the limits ... be quantified whenever the dataset is divided into subunits. Then gamma diversity is the total speciesdiversity in the dataset and alpha diversity the mean speciesdiversity per subunit. Beta diversity quantifies how many subunits there would be if the total speciesdiversity of the dataset and the mean speciesdiversity per subunit remained the same, but the subunits shared no species. ref name Tuomisto2010a ref name Tuomisto2010c Other meanings of beta diversity Absolute species turnover Some ... components. ref Lande, R. 1996 Statistics and partitioning of speciesdiversity, and similarity among ... of speciesdiversity recent revival of an old idea. Oikos, 99, 3 9. ref Then beta diversity becomes sub A sub This quantifies how much more speciesdiversity the entire dataset contains than an average ... by alpha diversity, a measure is obtained that quantifies how many times the species composition ..., R. H. 1972 Evolution and measurement of speciesdiversity. Taxon, 21, 213 251. ref so it has ... more details
Unreferenced stub auto yes date December 2009 Image BlueMarble 2001 2002.jpg thumb right 300px alt Two views of the Earth from space. The Earth has many diverse ecosystems and ecosystem diversity. These are NASA composite images of the Earth 2001 left , 2002 right , titled The Blue Marble . seealso Ecosystem Biome Ecosystem diversity refers to the diversity of a place at the level of ecosystem s. The term differs from biodiversity , which refers to variation in species rather than ecosystems. Ecosystem diversity can also refer to the variety of ecosystems present in a biosphere, the variety of species and ecological processes that occur in different physical settings. Examples Some examples of ecosystems that are rich in diversity are Refbegin 3 Deserts Forests Large marine ecosystem s Marine ecosystem s Old growth forest s Rainforest s Tundra Coral Reef s Refend See also Portal box Environment Ecology Earth sciences Sustainable development Refbegin 2 Bioregion Ecology Evolutionary biology Genetic diversity Nature Natural environment Species diversity Sustainable development Refend modelling ecosystems expanded other DEFAULTSORT Ecosystem Diversity Category Biodiversity Category Systems ecology Ecology stub es Diversidad ecol gica sl Ekosistemska diverziteta zh ... more details
Image Sphenodon punctatus in Waikanae, New Zealand.jpg thumb widthpx The two species of Tuatara are separated from all other species by over 200 million years Phylogenetic diversity is a measure of biodiversity which incorporates taxonomic difference between species. It is defined and calculated as the sum of the lengths of the all the branches that are members of the corresponding minimum spanning path , ref DP Faith. 1992. Conservation evaluation and phylogenetic diversity. Biological Conservation 61 1 10 ref in which branch is a segment of a cladogram , and the minimum spanning path is the mimimum distance between the two nodes. This definition is distinct from earlier measures which attempted to incorporate phylogenetic diversity into conservation planning, such as the measure of toxic diversity introduced by Vane Wright, Humphries, and William. ref Vane Wright, R. I., Humphries, C. J. & Williams, P. H. 1991. 1991 . What to protect systematics and the agony of choice. Biological Conservation, 55, 235 54. ref The concept of phylogenetic diversity has been rapidly adopted in conservation planning, with programs such as the Zoological Society of London s EDGE of Existence programme focused on evolutionary distinct species. Similarly, the World Wide Fund for Nature WWF s Global 200 also includes unusual evolutionary phenomena in their criteria for selecting target ecoregion s. Some studies have indicated that alpha diversity is a good proxy for phylogenetic diversity, so suggesting that term has little use, ref Rodrigues, A. S. L. & Gaston, K. J. 2002. Maximising phylogenetic diversity in the selection of networks of conservation areas. Biol. Conserv. 105, 103 111 ref but a study in the Cape Floristic Region showed that using phylogenetic diversity led to selection of different conservation priorities than using species richness. It also demonstrated that PD led to greater preservation of feature diversity than species richness alone. ref Forest, F. et al. 2007. Preserving ... more details
by the National Science Foundation found that genetic diversity and biodiversity Biodiversity is the degree of variation of life forms within a given ecosystem are dependent upon each other that diversity within a species is necessary to maintain diversity among species, and vice versa. According ... http www.enn.com animals article 23391 Study Loss Of Genetic Diversity Threatens SpeciesDiversity ... diversity lead to changes in the environment, leading to adaptation of the remaining species. Changes in genetic diversity, such as in loss of species, leads to a loss of biological diversity. ref name .... A species that has a large degree of genetic diversity among its population will have more variations from which to choose the most fit alleles. Increase in genetic diversity is also essential for a species ... ref Cheetah s are a threatened species . Extremely low genetic diversity and resulting poor sperm ...Evolutionary biology Genetic Diversity , the level of biodiversity , refers to the total number of Genetics genetic characteristics in the genetic makeup of a species. It is distinguished from genetic variability , which describes the tendency of genetic characteristics to vary. Genetic diversity serves ... to Genetic Diversity publisher U.S. Geological Survey url http www.nbii.gov portal server.pt ... 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. Disruptive selection Diversifying selection is the hypothesis that two subpopulations of a species ... occur, for instance, if a species has a large range relative to the mobility of individuals within ... to overcome that allele. Importance of genetic diversity There are many different ways to measure genetic diversity. The modern causes for the loss of animal genetic diversity have also been studied ... Clem Tisdell year 2003 title Socioeconomic causes of loss of animal genetic diversity analysis ... more details
of the diversity. It defines the sensitivity of the diversity value to rare vs. abundant species by modifying how the mean of the species proportional abundances is calculated. With some values ... species list. Richness is a simple measure, so it has been a popular diversity index in ecology ..., S.H. 1971 The nonconcept of speciesdiversity A critique and alternative parameters. Ecology 52, 577 ... to the same value of q . See also SpeciesdiversitySpecies richness Alpha diversity Beta diversity ...A diversity index is a quantitative measure that increases when the number of types into which a set ... when all types are represented by the same number of entities. When diversity indices are used in ecology ... are species or other Taxon taxa . In demography , the entities of interest can be people, and the types ... and the types the different letters of the alphabet. The most commonly used diversity indices are simple transformations of the effective number of types also known as true diversity , but each diversity index can also be interpreted in its own right as a measure corresponding to some real phenomenon but a different one for each diversity index . ref name Hill1973 Hill, M. O. 1973 Diversity ... Jost, L. 2006 Entropy and diversity . Oikos , 113, 363 375 ref ref name Tuomisto2010a Tuomisto, H. 2010 A diversity of beta diversities straightening up a concept gone awry. Part 1. Defining beta diversity as a function of alpha and gamma diversity . Ecography , 33, 2 22. doi 10.1111 j.1600 0587.2009.05880.x ref ref name Tuomisto2010c Tuomisto, H. 2010. A consistent terminology for quantifying speciesdiversity? Yes, it does exist . Oecologia 4 853 860. doi 10.1007 s00442 010 1812 0 ref True diversity The effective number of types True diversity, or the effective number of types, refers to the number ... that observed in the dataset of interest where all types may not be equally abundant . The true diversity ... math p i math value, which is the proportional abundance of the most abundant species in the dataset ... more details
, Hanage WP title The bacterial species challenge making sense of genetic and ecological diversity ... of fungal diversity the 1 5 million species estimate revisited journal Mycological Research volume ... diversity the 1 5 million species estimate revisited Mycological Research 2001 , 105 1422 1432 Cambridge ...Wiktionary species pp move indef Other uses Biological classification In biology , a species is one of the basic units of biological classification and a taxonomic rank . A species is often defined as a group ... species into infraspecific taxa such as subspecies and in botany other taxa are used, such as Variety botany varieties , subvarieties, and formae . Species that are believed to have the same ancestors are grouped together, and this group is called a genus . A species will be placed in only one genus ... , dubious reason a tiny DNA difference can divide species relatively large differences can occur between different individuals of the same species date March 2012 but for practical reasons, other properties are used. All species are given a binomial nomenclature two part name , a binomial name . The first part of a binomial name is the name of a biological genus generic name , the genus of the species ... in zoology . For example, Boa constrictor is one of four species of the Boa genus Boa genus. The first ... in italics. A usable definition of the word species and reliable methods of identifying particular species are essential for stating and testing biological theories and for measuring biodiversity ... between global taxonomic diversity, ecological diversity and the expansion of vertebrates on land ... 20106856 pmc 2936204 ref Extinct species known only from fossils are generally difficult to assign ... of non bacterial species in the world has been estimated at 8.7 million, ref name Guardian Cite news date 2011 08 23 title Planet Earth is home to 8.7 million species, scientists estimate url http www.guardian.co.uk environment 2011 aug 23 species earth estimate scientists accessdate 2011 08 23 postscript ... more details
species, ref cite journal title Molecular diversity at 18 loci in 321 wild and 92 domesticate lines reveal no reduction of nucleotide diversity during Triticum monococcum Einkorn domestication implications ...Nucleotide diversity is a concept in molecular genetics which is used to measure the degree of polymorphism biology polymorphism within a population. ref cite journal title Mathematical Model for Studying Genetic Variation in Terms of Restriction Endonucleases journal PNAS date October 1, 1979 first last coauthors Masatoshi Nei and Wen Hsiung Li volume 76 issue 10 pages 5269 73 pmid 291943 pmc 413122 url doi 10.1073 pnas.76.10.5269 author Nei, M. ref One commonly used measure of nucleotide diversity was first introduced by Nei and Li in 1979. This measure is defined as the average number of nucleotide differences per site between any two DNA sequences chosen randomly from the sample population, and is denoted by . It is given by the formula math pi sum ij x i x j pi ij 2 sum i 1 n sum j 1 i 1 x i x j pi ij math where x sub i sub and x sub j sub are the respective frequencies of the i th and j th sequences, sub ij sub is the number of nucleotide differences per nucleotide site between the i th and j th sequences, and n is the number of sequences in the sample. Nucleotide diversity ... diversity, and is similar to expected heterozygosity. This statistic may be used to monitor diversity ... relationships. ref cite journal title Nucleotide diversity in gorillas journal Genetics ... cgi pmidlookup?view long&pmid 15082556 author Yu, N. ref Nucleotide diversity can be calculated ... Amplified Polymorphic DNA RAPD data ref cite journal title Estimating nucleotide diversity from ... Length Polymorphism AFLP data. ref cite journal title A method for estimating nucleotide diversity ... of nucleotide diversity and a variety of other statistical tests for intra population and inter ... Reflist DEFAULTSORT Nucleotide Diversity Category Molecular genetics genetics stub ar ... more details
Cultural diversity is the quality of diverse or different cultures, as opposed to monoculture, as in the global ... to the world s cultural diversity. Now Hawaii has been westernized the vast majority of its culture has been replaced with Western or American culture. The phrase cultural diversity can ... 2011 The phrase cultural diversity is sometime misused to mean the variety of human societies or culture ... rather than cultural diversity. The culturally destructive action of globalization is often said to have a negative effect on the world s cultural diversity. Overview The many separate societies that emerged .... Cultural diversity can be seen as analogous to biodiversity . ref Universal Declaration on Cultural Diversity , Article 1 ref Opposition and Support By analogy with biodiversity, which is thought to be essential to the long term survival of life on earth, it can be argued that cultural diversity ... s may be as important to humankind as the conservation of species and ecosystem s is to life in general ... Declaration on Cultural Diversity that ...cultural diversity is as necessary for humankind as biodiversity ... 127160m.pdf UNESCO Universal Declaration on Cultural Diversity , 2001 ref This position is rejected ... of human nature , the importance of cultural diversity for survival may be an un testable hypothesis ... way it is unethical to promote poverty in underdeveloped nations as cultural diversity it is also unethical to promote all religious practices simply because they contribute to cultural diversity ... diversity globalization&ots 4hCqw31ynN&sig SdC3X2x9byFJQIFlUPbhYiXgfsc v onepage&q ifg 20cultural ... to support social changes that some observers would consider detrimental to cultural diversity by seeking ... culture diversity. Their goal is to broaden their horizontal and develop themselves from learning ... the culture diversity and those make our world more colorful. For students who go abroad for education .... Web. 7 Nov. 2011. Quantification Cultural diversity is tricky to quantify, but a good indication ... more details
and species sustainability . ref Jarvis, Devra I. and Camplain, Dindo M. Crop genetic diversity ...Crop diversity is the variance in genetics genetic and phenotype phenotypic characteristics of plants ..., it can often be found in a wild relative of the crop a plant that has similar species that have not been .... Bioversity International, Dec 5 2008 ref Diversity in a crop can also result from different growing ... fertile soil. In addition, and perhaps most importantly, diversity of a harvested plant can be the result .... The practical use of crop diversity goes back to early agricultural methods of crop rotation and fallow ... continually draw on the irreplaceable resource of genetic diversity to ensure productive harvests, as genetic ... plant species could face extinction . ref Associated Press. Threat seen to half of Earth s plant species. The Milwaukee Journal Sentinel Milwaukee, WI . November 1, 2002 ref Among the many threatened species are wild relatives of our crops species that could contribute invaluable traits to future ..., sorghum etc. are under threat as are 18 of legume species the wild relatives of beans, peas and lentils and 13 of species within the botanical family that includes potato, tomato, eggplant, and pepper ... genetic diversity in plant breeding can contribute significantly to protecting the environment ... of crop diversity for sustainable landscape development. Management of Environmental Quality. Vol ... lands to create more farmland for food production. Crop diversity and the economy Agriculture is the economic ... solutions is crop diversity the diversity that enables farmers and plant breeders to develop ... and better insulating poor farmers from risk. ref Smale, Melinda and King, Amanda. What is Diversity ... in fighting poverty is complex, but without the genetic diversity found within crops, it cannot fulfill its potential. Disease threats to crops with low genetic diversity One particular threat to mass producing plants for harvest is their susceptibility to diseases. Generally speaking, a species has ... more details
A center of diversity is an area that has a high degree of genetic variation for a particular species or genus of plants that can also be the center of origin for that species. The two areas often, but not always, coincide the degree of coincidence remains the subject of debate. ref name aps cite web title Knowledge Test Questions and Answers for Discussion publisher The American Phytopathological Society url http www.apsnet.org education InstructorCommunication Restricted Advanced discussion population genetics.html accessdate 2008 12 18 Dead link date October 2010 bot H3llBot ref ref name osu cite web title Centers of Diversity, Crop Adaptation publisher Oregon State University url http oregonstate.edu instruct css 330 two accessdate 2008 12 18 ref In both areas, organisms have had the opportunity over many generations to evolve resistance, via mutation , to their pathogen s. ref name aps The term was created by the Russian scientist Nikolai Vavilov and the U.S. scientist Jack Harlan . ref name ac cite book author George Acquaah title Principles of plant genetics and breeding year 2006 publisher Blackwell Publishing url http books.google.com books?id Xrwvjo2myTMC&pg PA19&dq 22center of diversity 22 vavilov concept&ei kSRISb6sDZCqkATO 9jwDw isbn 9781405136464 ref Vavilov published a study in 1926 Studies on the Origin of Cultivated Plants describing ten such centers 1 China for lettuce , rhubarb , soybean , and turnip 2 India for cucumber , rice , mango , and Asian cotton 2a Indochina for banana , coconut , and rice 3 Central Asia north India , Afghanistan , and Turkmenistan for almond , flax , and lentil 4 Near East for alfalfa , apple , cabbage , and rye 5 Coastal and adjacent areas of the Mediterranean Sea for celery , chickpea s, and durum wheat 6 Ethiopia for coffee ... modified the concept to include secondary centers of diversity. ref name osu References reflist See also Biodiversity hotspot Coevolution Domestication Crop diversity Category Ecology terminology ... more details
Functional diversity is a politically and socially correct term for special needs , disability , impairment and handicap , which began to be used in Spain in scientific writing, at the initiative of those directly affected, in 2005. ref cite paper title Functional diversity, a new term in the struggle for dignity in the diversity of the human being author Javier Roma ach and Manuel Lobato work Independent Living Forum Spain &mdash May 2005 format PDF url http www.leeds.ac.uk disability studies archiveuk zavier Functional 20Diversity 20 20 20 20 20 20 20 20 20 20 fv 20Roma F1ach.pdf ref This term is intended to replace other ones with pejorative semantics. It proposes a shift towards non negative, non disparaging and non patronizing terms. The formal justification of the term can be found in the book El Modelo de la Diversidad by Agustina Palacios and Javier Roma ach, 2007, ISBN 978 84 964 7440. Examples of usage people with functional diversity instead of people with special needs physical functional diversity mobility functional diversity , person who uses a wheelchair , wheelchair user motor functional diversity dexterity functional diversity visual functional diversity , people who use screen readers as their primary means of accessing a computer people with a visual processing functional diversity auditory functional diversity mental functional diversity intellectual functional diversity cognitive functional diversity organic functional diversity circumstantial and or temporary functional diversity person with a functional diversity persons without functional diversity rather than normal or healthy people without functional diversity , typically developing children References reflist Further reading cite journal journal Disabil Rehabil. date 2007 Oct 30&ndash Nov 15 volume 29 issue 20&ndash 21 pages 1625&ndash 1633 title Constructive Functional Diversity a new paradigm beyond disability and impairment. author Patston P. pmid 17896220 doi 10.1080 09638280701618778 ... more details
In wireless communications, diversity gain is the increase in signal to interference ratio due to some diversity scheme , or how much the transmission power can be reduced when a diversity scheme is introduced, without a performance loss. Diversity gain is usually expressed in decibel , and sometimes as a power ratio. An example is soft handoff gain. For selection combining N signals are received, and the strongest signal is selected. When the N signals are independent and Rayleigh distributed, the expected diversity gain has been shown to be math sum k 1 N frac 1 k math , expressed as a power ratio. ref D.G. Brennan, Linear diversity combining techniques, Proc. IRE , vol.47, no.1, pp.1075 1102, June 1959 ref See also Array gain Diversity combining References references Category radio resource management Wireless stub ... more details
Unreferenced stub auto yes date December 2009 Transmit diversity is radio communication using signals that originate from two or more independent sources that have been modulation modulated with identical information bearing signals and that may vary in their transmission characteristic s at any given instant. It can help overcome the effects of fading , outages, and Electronic circuit circuit failures. When using diversity transmission and reception, the amount of received signal improvement depends on the independence of the fading characteristics of the signal as well as circuit outages and failures. See also Antenna diversityDiversity gain Diversity scheme Dynamic Single Frequency Networks DSFN Macro diversity Multiple input multiple output communications MIMO Single frequency networks SFN Space time block coding based transmit diversity STTD Soft handover DEFAULTSORT Transmit Diversity Category Radio resource management Wireless stub ... more details
Unreferenced date December 2008 Notability Notability date December 2008 Diversity coding is a particular technique for antenna diversity and is implemented by Space time code space time coding . Category Radio resource management wireless stub ... more details
configured for space diversity In telecommunications , a diversity scheme refers to a method for improving ... channels with different characteristics. Diversity plays an important role in combatting fading and co .... Diversity techniques may exploit the multipath propagation , resulting in a diversity gain , often measured in decibels . The following classes of diversity schemes can be identified Time diversity .... Frequency diversity The signal is transmitted using several frequency channels or spread over ... or DS CDMA . Space diversity The signal is transmitted over several different propagation paths. In the case ... of wireless transmission, it can be achieved by antenna diversity using multiple transmitter antennas transmit diversity and or multiple receiving antennas reception diversity . In the latter case, a diversity ... macrodiversity or site diversity . If the antennas are at a distance in the order of one ... diversity Multiple versions of a signal are transmitted and received via antennas with different polarization. A diversity combining technique is applied on the receiver side. Multiuser diversity Multiuser diversity is obtained by opportunistic user scheduling at either the transmitter or the receiver ... quality information to the transmitter with the limited level of resolution. Cooperative diversity Achieves antenna diversity gain by using the cooperation of distributed antennas belonging to each node. See also Space time coding STC Antenna diversity Macrodiversity Diversity combining Aperture synthesis Cooperative diversity Channel access method Fresnel zone Tropospheric scatter External links http www.radioblvd.com DiversityDD1.html Diversity reception Background information of the development of Diversity reception devices. http www.antenna theory.com arrays diversity.php Antenna Diversity Tutorial www.Antenna Theory.com K. T. Wong http www.eie.polyu.edu.hk enktwong & A. K. Y. Lai ... diversity 2 in mobile handsets technologies , see Christian Le Floc h, Regis Duval,Gerard ... more details
Unreferenced stub auto yes date December 2009 Site diversity is a technique to limit the effect of rain fade in satellite communications , mainly in the Ka band . The downlink transmissions of satellites cover very large areas, that will have different weather. The site diversity technique consists of linking two or more ground stations receiving the same signal this way, if the signal is heavily attenuated in one area, another ground stations can compensate it. These intense rain areas, for example supercell s, often have a horizontal length of no more than a few kilometres putting the ground stations at a sufficient distance the possibility of rain fade in the downlink signal will be reduced. The configuration works when the attenuation is not great at the two stations simultaneously. This is usually a valid assumption. Site diversity systems have been known to minimize disruption of service by major satellite carriers. See also Diversity scheme Diversity combining DEFAULTSORT Site Diversity Category Satellite television Comm stub zh ... more details
Biocultural diversitydiversity of life in all its manifestations biology biological , culture cultural , and linguistics linguistic which are interrelated within a complex socio ecological adaptive system. ref http portal.unesco.org education en ev.php URL ID 18391&URL DO DO TOPIC&URL SECTION 201.html UNESCO web page on biocultural diversity ref See also Portal box Ecology Environment Sustainable Development Biocultural anthropology Biocultural evolution Conservation movement Cultural landscape Ecology Ecosystem Environmental protection Terralingua http www.terralingua.org bcdconservation Biocultural Diversity Conservation References Reflist External links http www.unesco.org mab doc iyb icbcd working doc.pdf UNESCO web page on biocultural diversity http www.terralingua.org Terralingua http www.terralingua.org bcdconservation Biocultural Diversity Conservation Category Biodiversity Category Anthropology environment stub anthropology stub ... more details
Orphan date November 2006 Normgiving Diversity is a former public taxpayer funded program in Sweden , Europe, aimed at encouraging acceptance of lesbian s, Bisexuality bisexuals and gay men in public institutions such as the army, police, etc. External links http www.normgivande.nu NG english.asp Normgiving Diversity Dead link date August 2010 Category Swedish society Sweden stub ... more details
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