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生物多样性的益处之五： 休闲、 文化和审美价值

8. Leisure, cultural and aesthetic value

Many people derive value from biodiversity through leisure activities such as

hiking in the countryside, bird-watching or natural history study.

Biodiversity has inspired musicians, painters, sculptors, writers and other

artists. Many cultural groups view themselves as an integral part of the natural

world and show respect for other living organisms.

Popular activities such as gardening, caring for aquariums and collecting

butterflies are all strongly dependent on biodiversity. The number of species

involved in such pursuits is in the tens of thousands, though the great majority

does not enter mainstream commercialism.

作物多样性有助于其遭疾病侵袭后的恢复

Crop diversity is also necessary to help the system recover when the dominant

crop type is attacked by a disease, for instance:

The Irish potato blight of 1846, which killed a million people and forced

another million to emigrate, was the result of planting only two potato

varieties, both of which were vulnerable.

When the rice grassy stunt virus struck rice fields from Indonesia to India

in the 1970s, 6,273 varieties were tested. Only one was luckily found to be

resistant, a relatively feeble Indian variety, known to science only since 1966,

with the desired trait. It was hybridized with other varieties and now widely

grown.

生物多样性面临的威胁

During the last century, erosion of biodiversity has been increasingly

observed. Some studies show that about one eighth known plant species is

threatened with extinction. Some estimates put the loss at up to 140,000 species

per year (based on Species-area theory) and subject to discussion. This figure

indicates unsustainable ecological practices, because only a small number of

species come into being each year. Almost 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.

Declines in amphibian populations have been observed since 1980s. Because of

the sensitivity of these organisms, they are regarded by many scientists as a

marker for the overall health of an ecosystem. Their decline has led to concern

about the general current state of biodiversity.

国际协议对生物多样性的动态保护

New global agreements (e.g.Convention on Biological Diversity), now give

sovereign national rights over biological resources (not property). The idea of

static conservation of biodiversity is disappearing and being replaced by the

idea of dynamic conservation, through the notion of resource and innovation.

Sovereignty principles can rely upon what is better known as Access and

Benefit Sharing Agreements (ABAs). The Convention on Biodiversity spirit implies

a prior informed consent between the source country and the collector, to

establish which resource will be used and for what, and to settle on a fair

agreement on benefit sharing. Bioprospecting can become a type of biopiracy when

those principles are not respected.Uniform approval for use of biodiversity as a

legal standard has not been achieved, however. At least one legal commentator

has argued that biodiversity should not be used as a legal standard, arguing

that the multiple layers of scientific uncertainty inherent in the concept of

biodiversity will cause administrative waste and increase litigation without

promoting preservation goals.