一壶老酒歌曲原唱简谱:什么叫生物多样性?

从研究最微小的生命组成部分，到植物和动物。而“多样性”简单来说就是“各种各样”的意思。生物多样性包括所有自然世界的资源，包括植物、动物、昆虫、微生物和它们生存的生态系统。它同样包括构造出生命的重要基石--染色体、基因和脱氧核糖核酸。

生物多样性包括四个层次,遗传多样性,群落多样性,生态系统多样性,景观多样性.

给你哥英文的介绍
生物多样性
Biodiversity
http://en.wikipedia.org/wiki/Biodiversity

Biodiversity
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Biodiversity or biological diversity is the diversity of and in living nature. There are a number of definitions and measures of biodiversity.
Contents
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* 1 Etymology
* 2 Biodiversity definitions
* 3 Origin of life and biodiversity evolution
* 4 Benefits of biodiversity
o 4.1 Ecological role of biodiversity
o 4.2 Economic role of biodiversity
o 4.3 Ethical role of biodiversity
o 4.4 Scientific role of biodiversity
* 5 Evaluation of biodiversity
o 5.1 Measurement of biodiversity
o 5.2 Biodiversity: time and space
o 5.3 Species inventory
o 5.4 Hotspots of biodiversity
* 6 Threats to biodiversity
* 7 Biodiversity management: conservation, preservation and protection
* 8 Juridical status of biological diversity
* 9 Biodiversity and size bias
o 9.1 Quotes from Sean Nee
* 10 Measures of biodiversity
* 11 See also
* 12 External links
o 12.1 Directories

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Etymology

Biodiversity is a neologism and a portmanteau word, from bio and diversity. The term biological diversity was coined by Thomas Lovejoy in 1980, while the word biodiversity itself was coined by the entomologist E. O. Wilson in 1986, in a report for the first American Forum on biological diversity organized by the National Research Council (NRC). The word biodiversity was suggested to him by the staff of NRC, to replace biological diversity, considered to be less effective in terms of communication.

Since 1986 the terms and the concept have achieved widespread use among biologists, environmentalists, political leaders, and concerned citizens worldwide. This use has coincided with the expansion of concern over extinction observed in the last decades of the 20th century.
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Biodiversity definitions

Biodiversity is the variety of life: the different plants, animals and micro-organisms, their genes and the ecosystems of which they are a part.

Biological diversity has no single standard definition. One definition holds that biological diversity is a measure of the relative diversity among organisms present in different ecosystems. Diversity in this definition includes diversity within species and among species, and comparative diversity among ecosystems.

Another definition, simpler and clearer, but more challenging, is the totality of genes, species, and ecosystems of a region. An advantage of this definition is that it seems to describe most instances of its use, and one possibly unified view of the traditional three levels at which biodiversity has been identified:
Intraspecific diversity within Dog
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Intraspecific diversity within Dog

* genetic diversity - diversity of genes within a species. There is a genetic variability among the populations and the individuals of the same species
* species diversity - diversity among species
* ecosystem diversity - diversity at a higher level of organization, the ecosystem (richness in the different processes to which the genes ultimately contribute)

The lattermost definition, which conforms to the traditional five organisation layers in biology, provides additional justification for multilevel approaches.

The 1992 United Nations Earth Summit in Rio de Janeiro defined biodiversity as "the variability among living organisms from all sources, including, inter alia, terrestrial, marine, and other aquatic ecosystems, and the ecological complexes of which they are part: this includes diversity within species, between species and of ecosystems".

This is, in fact, the closest thing to a single legally accepted definition of biodiversity, since it is the definition adopted by the United Nations Convention on Biological Diversity. The parties to this convention include all the countries on Earth, with the exception of Andorra, Brunei Darussalam, the Holy See, Iraq, Somalia, Timor-Leste, and the United States of America.

If the gene is the fundamental unit of natural selection, thus of evolution, some, like E. O. Wilson, say that the real biodiversity is the genetic diversity. However, the species diversity is the easiest one to study.

For geneticists, biodiversity is the diversity of genes and organisms. They study processes such as mutations, gene exchanges, and genome dynamics that occur at the DNA level and generate evolution.

For biologists, biodiversity is the diversity of populations of organisms and species, but also the way these organisms function. Organisms appear and disappear; sites are colonized by organisms of the same species or by another. Some species develop social organisations to improve their reproduction goals or use neighbor species that live in communities. Depending on their environment, organisms do not invariably use the same strategies of reproduction.

For ecologists, biodiversity is also the diversity of durable interactions among species. It not only applies to species, but also to their immediate environment (biotope) and the ecoregions the organisms live in. In each ecosystem, living organisms are part of a whole; they interact with one another, but also with the air, water, and soil that surround them.
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Origin of life and biodiversity evolution
Apparent marine fossil diversity during the Phanerozoic
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Apparent marine fossil diversity during the Phanerozoic

See also biodiversity and evolution

Biodiversity found on Earth today is the result of 4 billion years of evolution.

The original origin of life is not well known to science, though limited evidence suggests that life may already have been well-established only a few 100 million years after the formation of the Earth. Until approximately 600 million years ago, all life consisted of bacteria and similar single-celled organisms.

The history of biodiversity during the Phanerozoic (the last 540 million years), starts with rapid growth during the Cambrian explosion—a period during which nearly every phylum of multicellular organisms first appeared. Over the next 400 million years or so, global diversity showed little overall trend, but was marked by periodic, massive losses of diversity classified as mass extinction events.

The apparent biodiversity shown in the fossil record suggests that the last few million years include the period of greatest biodiversity in the Earth's history. However, not all scientists support this view, since there is considerable uncertainty as to how strongly the fossil record is biased by the greater availability and preservation of recent geologic sections. Some (e.g. Alroy et al. 2001) argue that corrected for sampling artifacts, modern biodiversity is not much different than biodiversity 300 million years ago. Estimates of the present global macroscopic species diversity vary from 2 million to 100 million species, with a best estimate of somewhere near 10 million.

Most biologists agree however that the period since the emergence of humans is part of a new mass extinction, the Holocene extinction event, caused primarily by the impact humans are having on the environment. At present, the number of species estimated to have gone extinct as a result of human action is still far smaller than are observed during the major mass extinctions of the geological past. However, it has been argued that the present rate of extinction is sufficient to create a major mass extinction in less than 100 years. Others dispute this and suggest that the present rate of extinctions could be sustained for many thousands of years before the loss of biodiversity matches the more than 20% losses seen in past global extinction events.

New species are regularly discovered (on average about three new species of birds each year) and many, though discovered, are not yet classified (an estimate states that about 40% of freshwater fish from South America are not yet classified). Most of the terrestrial diversity is found in tropical forests.
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Benefits of biodiversity

Biodiversity has contributed in many ways to the development of human culture, and, in turn, human communities have played a major role in shaping the diversity of nature at the genetic, species, and ecological levels.

There are three main reasons commonly cited in the literature for the benefits of biodiversity.
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Ecological role of biodiversity

All species provide some kind of function to an ecosystem. They can capture and store energy, produce organic material, decompose organic material, help to cycle water and nutrients throughout the ecosystem, control erosion or pests, fix atmospheric gases, or help regulate climate.

Ecosystems also provide various supports of production (soil fertility, pollinators of plants, predators, decomposition of wastes...) and services such as purification of the air and water, stabilisation and moderation of the climate, decrease of flooding, drought, and other environmental disasters.

These functions are important for ecosystem function and human survival.

Research suggests that a more diverse ecosystem is better able to withstand environmental stress and consequently is more productive. The loss of a species is thus likely to decrease the ability of the system to maintain itself or to recover from damage or disturbance. Just like a species with high genetic diversity, an ecosystem with high biodiversity may have a greater chance of adapting to environmental change. In other words, the more species comprising an ecosystem, the more stable the ecosystem is likely to be. The mechanisms underlying these effects are complex and hotly contested. In recent years, however, it has become clear that there are real ecological effects of biodiversity.
Unusual and wild strains of maize are collected to increase the crop diversity when selectively breeding domestic corn.
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Unusual and wild strains of maize are collected to increase the crop diversity when selectively breeding domestic corn.
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Economic role of biodiversity

For all humans, biodiversity is first a resource for daily life. One important part of biodiversity is 'crop diversity', which is also called agrobiodiversity.

Most people see biodiversity as a reservoir of resources to be drawn upon for the manufacture of food, pharmaceutical, and cosmetic products. This concept of biological resources management probably explains most fears of resources disappearance related to the erosion of the biodiversity. However, it is also the origin of new conflicts dealing with rules of division and appropriation of natural resources.

Some of the important economic commodities that biodiversity supplies to humankind are:

* food : crops, livestock, forestry, and fish; (see also local food)
* medication. Wild plant species have been used for medicinal purposes since before the beginning of recorded history. For example, quinine comes from the cinchona tree (used to treat malaria), digitalis from the foxglove plant (chronic heart trouble), and morphine from the poppy plant (pain relief). According to the National Cancer Institute, over 70 % of the promising anti-cancer drugs come from plants in the tropical rainforests. Animals may also play a role, in particular in research. It is estimated that of the 250,000 known plant species, only 5,000 have been researched for possible medical applications.
* industry : for example, fibers for clothing, wood for shelter and warmth. Biodiversity may be a source of energy (such as biomass). Other industrial products are oils, lubricants, perfumes, fragrances, dyes, paper, waxes, rubber, latexes, resins, poisons, and cork, which can all be derived from various plant species. Supplies from animal origin include wool, silk, fur, leather, lubricants, and waxes. Animals may also be used as a mode of transport.
* tourism and recreation : biodiversity is a source of economical wealth for many areas, such as many parks and forests, where wild nature and animals are a source of beauty and joy for many people. Ecotourism, in particular, is a growing outdoor recreational activity.

Ecologists and environmentalists were the first to insist on the economic aspect of biological diversity protection. Thus, E. O. Wilson wrote in 1992 that : The biodiversity is the one of the bigger wealths of the planet, and nevertheless the less recognized as such.

Estimation of the value of biodiversity is a necessary precondition to any discussion on the distribution of biodiversity richnesses. This value can be divided into use value (direct such as tourism or indirect such as pollination) and non-use or intrinsic value.

If biological resources represent an ecological interest for the community, their economic value is also increasing. New products are developed because of biotechnologies, and new markets created. For society, biodiversity also is a field of activity and profit. It requires a proper management setup to determine how these resources are to be used.

The majority of species have yet to be evaluated for their current or future economic importance.
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Ethical role of biodiversity

Finally, biodiversity has an ethical role if humans consider that other species have an intrinsic right to exist. Ecophilosophies such as deep ecology assert that a recognition of this intrinsic right makes it morally wrong to voluntarily cause extinction. The level of biodiversity is a good indicator of the state of our relationships with other living species. Biodiversity is also part of many cultures' spiritual heritage (see indigenous people and cultural diversity).
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Scientific role of biodiversity

This is a fourth benefit separate from the three main ones. Biodiversity is important because each species can give scientists some clue as to how life evolved and will continue to evolve on Earth. In addition, biodiversity helps scientists understand how life functions and the role of each species in sustaining ecosystems.

See also Environmental economics
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Evaluation of biodiversity
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Measurement of biodiversity

From the viewpoint previously defined, no single objective measure of biodiversity is possible, only measures relating to particular purposes or applications.

For practical conservationists, this measure should quantify a value that is at the same time broadly shared among locally affected people.

For others, a broader and economically more defensible definition is that measures should allow the ensuring of continued possibilities for both adaptation and future use by people, assuring environmental sustainability. As a consequence, biologists argued that this measure is likely to be associated with the variety of genes. Since it cannot always be said which genes are more likely to prove beneficial, the best choice for conservation is to assure the persistence of as many genes as possible.

For ecologists, this approach is sometimes considered inadequate and too restricted.
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Biodiversity: time and space

Biodiversity is not static: it is a system in constant evolution, from a species, as well as from an individual organism point of view. The average half-life of a species is estimated at between one and four million years, and 99% of the species that have ever lived on earth are today extinct.

Biodiversity is not distributed evenly on earth. It is consistently richer in the tropics. As one approaches polar regions one finds larger and larger populations of fewer and fewer species. Flora and fauna vary depending on climate, altitude, soils and the presence of other species. For a listing of distinct ecoregions based on these distributions, see the WikiProject Ecoregions.
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Species inventory

Systematics assesses biodiversity simply by distinguishing among species. At least 1.75 million species have been described; however, the estimates of the true number of current species range from 3.6 to more than 100 million. Some also say that the knowledge of the species and the families became insufficient and must be supplemented by a greater comprehension of the functions, interactions and communities. Moreover, exchanges of genes occurring between the species tend to add complexity to the inventory.
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Hotspots of biodiversity

One definition of a biodiversity hotspot is a region with many endemic species. These biodiversity hotspots were first identified by Dr. Norman Myers in two articles in the scientific journal The Environmentalist (1988 and 1990). Hotspots unfortunately tend to occur in areas of significant human impact, leading to threats to their many endemic species. As a result of the pressures of the growing human population, human activity in many of these areas is increasing dramatically. Most of these hotspots are located in the tropics and most of them are forests.

Some examples are the following:

* Brazil's Atlantic Forest contains roughly 20,000 plant species, 1,350 vertebrates, and millions of insects, just under half of which are thought to occur nowhere else in the world.

See also: biogeography, Amazonian forest, extinction, unified neutral theory of biodiversity.
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Threats to biodiversity

During the last century, erosion of biodiversity has been increasingly observed. Estimates of extinction rates are controversial, ranging from very low to upwards of 200 species a day, but all scientists acknowledge that the rate of species loss is greater now than at any time in human history, with extinctions occurring at rates hundreds of times higher than background extinction rates.

Some studies show that about one of eight known plant species is threatened with extinction. Some estimates put the loss at thousands of species per year, though these are based on Species-area theory and are controversial. This figure indicates unsustainable ecological practices, because only a small number of species come into being each year. All agree that the losses are due to human activities, in particular destruction of plant and animal habitats.

An increasing number of studies indicate that elevated rates of extinction are being driven by human consumption of organic resources. While most of the species that are becoming extinct are not food species, their biomass is converted into human food when their habitat is transformed into pasture, cropland, and orchards. It is estimated that more than 40% of the Earth's biomass is tied up in only the few species that represent humans, our livestock and crops. Because an ecosystem decreases in stability as its species are made extinct, these studies warn that the global ecosystem is destined for collapse if it is further reduced in complexity.

Some justify this situation not so much by a species overuse or ecosystem degradation as by their conversion in very standardized ecosystems (e.g., monoculture following deforestation). Before 1992, others pointed out that no property rights or no access regulation of resources necessarily lead to their decrease (degrading costs having to be supported by the community).

Dissenters (notably economist Bjørn Lomborg) argue that there is not enough data to support the view of mass extinction, and say abusive extrapolations are being made on the global destruction of rainforests, coral reefs, mangrove swamps, and other rich habitats.

There is also a growing awareness that the movement and the introduction of exotic species around the world by humans is a potent threat to biodiversity.

When exotic species are introduced to ecosystems by humans and establish self-sustaining populations, the endemic species in that ecosystem, that have not evolved to cope with the ex

提到生物多样性，大多数人头脑中可能只是个关于动植物种类的简单概念。然而，在巴黎召开的生物多样性国际会议上，不少专家指出，这是人们对生物多样性概念的许多误解之一。
生物多样性概念是20世纪80年代首次被提出的。1992年里约地球峰会正式推广了这一概念，它指所有地球上的生物以及它们呈现的不同遗传特性和多样化的生态系统。在现存1000万到3000万物种中，有约130万到150万面临生存威胁。如今，各类生态系统遭到的破坏及其对环境变化适应力的减退，比以往估计的更为严重。

地球上生存着多种多样的生物，每一个种群都有自己的基因库，不同的种群有不同的基因库，这就是基因的多样性，即遗传的多样性。遗传的多样性构成了物种的多样性、物种的多样性构成了生态系统的多样性。因为基因是物种的组成部分，物种是生态系统的组成部分。因此，遗传的多样性、物种的多样性和生态系统的多样性，是从微观到宏观，在三个不同水平上来研究和分析生物多样性的基本特点。其中基因是生物多样性概念的基础，物种是生物多样性概念的中心，生态系统是生物多样性概念关键环节。
生物多样性是包括地球上所有植物、动物、微生物和它们拥有的基因以及由这些生物和环境构成的生态系统；是生物进化留下来的宝贵财富；是人类社会赖以生存和发展的基础。保护生物多样性就是在基因、物种和生态系统三个水平上采取保护战略和保护措施。

生物多样性的价值。
野生生物是与人工驯养、种植的动植物相比较而言，泛指那些在野外生活的植物、动物和微生物，它们所拥有的全部基因以及各种各样的生态系统。因此，野生生物资源是组成生物多样性的一个重要方面。野生生物资源具有直接使用价值、间接使用价值和潜在使用价值，是人类赖以生存的重要物质基础。只有全面认识野生生物资源的价值所在，才能增强并树立保护野生生物资源的意识、规范人们的行为方式，采取具体措施保护野生生物资源并加以合理利用，使野生生物资源世世代代地、可持续地为人类造福。
1．直接使用价值
野生生物的直接使用价值包括：①药用价值：如青蒿素是一种野生植物中的一种生物碱，是治疗疟疾的特效药物；②重要的工业原料：如从一种叫霍霍巴的灌木中提炼出油脂可替代鲸的油脂作为高级润滑油的原料；③科学研究价值：如一种寄生于葡萄根部的蚜虫从北美传到欧洲、使所有葡萄园几乎都遭到毁灭，后来人们发现美国的一种野生葡萄能够抵抗这种蚜虫，科学家利用这一特性，把欧洲葡萄嫁接到美洲葡萄砧木上，才使欧洲葡萄逃脱了毁灭的厄运；又如杂交水稻之父袁隆平利用野生雄性不育稻和栽培稻杂交，培育出杂交水稻“野败”，在解决世界粮食短缺问题方面引起了全球的关注。总之，野生生物是培育生物新品种不可缺少的基因库；④美学价值：如“花园城市”的建设离不开色彩纷呈的各种植物，名山大川与五颜六色的花鸟鱼虫相配合，才构成令人赏心悦目、流连忘返的美景；⑤文学创作的素材：如我国古代文学和现代文学作品中，有许多描写植物或借植物抒发情怀的诗句或作品。苏轼的“竹外桃花三两枝，春江水暖鸭先知”，将早春的暖意和生机描写得细致入微。茅盾的《白杨礼赞》、陶铸的《松树的风格》、朱自清的《荷塘月色》，都借植物抒发高洁的情怀，产生了广泛的影响。因此，生物多样性能激发人们文学艺术创作的灵感。
2．间接使用价值
间接使用价值是指生物多样性具有重要的生态功能。任何一个生态系统都是由生物群落和无机环境构成的，野生生物则是构成生物群落中生产者、消费者和分解者的重要成分。在生态系统中，野生生物之间具有相互依存和相互制约的关系，共同维系着生态系统的结构和功能，维持生态系统的稳定性。如果野生生物资源受到破坏，势必影响生态系统的稳定性，进而影响人类的生存与发展。
3．潜在使用价值
潜在使用价值是指目前人们还不清楚的但肯定具有的巨大的使用价值。一种野生生物一旦从地球上消失，就无法再生，它的各种潜在的使用价值也就不复存在了。

其实说到生物多样性，是说组成大多数生物染色体的核苷酸类别有5种，高数量的碱基对就有无数的排列方式。DNA空间构形也有不同，所以在合成蛋白质时就有多种性状，即多样性。

是指不同的生物在一起生存在一个星球上