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生态系统的管理

The conservation of biological diversity has become a global concern.

Although not everybody agrees on extent and significance of current extinction,

most consider biodiversity essential. There are basically two main types of

conservation options, insitu conservation and ex-situ conservation. In-situ is

usually seen as the ideal conservation strategy. However, its implementation

is

sometimes infeasible. For example, destruction of rare or endangered species‟

habitats sometimes requires ex-situ conservation efforts. Furthermore, ex-situ

conservation can provide a backup solution to in-situ conservation projects.

Some believe both types of conservation are required to ensure proper

preservation. An example of an in-situ conservation effort is the setting-up of

protection areas. Examples of ex-situ conservation efforts, by contrast, would

be planting germplants in seedbanks, or growing the Wollemi Pine in nurseries.

Such efforts allow the preservation of large populations of plants with minimal

genetic erosion.

生态系统的内在价值

Some people criticize the notion that the intrinsic value of ecological

systems exists independently of humanity‟s recognition of it. An example of this

approach is that one might say that a work of art is only valuable insofar as

humans perceive it to be worthwhile. Such people claim that the ecosystem‟s

value does not reach beyond our appreciation of it. Intrinsic value is a

philosophical concept which some do not accept. However, intrinsic value defined

as value existing separate from human thought may in this case be conflated with

intrinsic value defined as natural worth existing independent of modification or

application of a substance or entity, clouding the argument. This entire

argument, however, assumes both the primacy and uniqueness of the ability of

humans to create value, as opposed to a collection of sentient beings dependent

on a perfectly ordered system for life or even a natural system devoid of

sentient life being incapable of possessing inherent value. It also is a result

of the confusion between anthropogenic—something being created by humans, and

anthropocentric—exclusive value being given to humans.

生物多样性的定义

The most straightforward definition biodiversity is “variation of life at all

levels of biological organization”. A second definition holds that biodiversity

is a measure of the relative diversity among organisms present in different

ecosystems. “Diversity” in this definition includes diversity within a species

and among species, and comparative diversity among ecosystems.

A third definition that is often used by ecologists is the “totality of

genes, species, and ecosystems of a region”. An advantage of this definition is

that it seems to describe most circumstances and present a unified view of the

traditional three levels at which biodiversity has been identified:

1. Genetic diversity—diversity of genes within a species. There is a genetic

variability among the populations and the individuals of the same species.

2. Species diversity—diversity among species in an ecosystem. “Biodiversity

hotspots” are excellent examples of species diversity.

3. Ecosystem diversity—diversity at a higher level of organization, the

ecosystem.