Overexploitation

Consequences of overexploitation

The surexeploitation can relate to whole or part of the Environnement (ecosystems, subterranean water, etc) and can lead to various detrimental consequences:

threats on the plant species or animal and reached with the Biodiversity,
rarefaction of the nonrenewable Resources,
degradation of the natural balances.

Measure overexploitation

The ecological concept of Empreinte was defined to contribute to treat this type of problem, but can approach it only on its quantitative aspects. The limit from which one can say that a biologically productive medium is “ overexploited ” is often very difficult to define; The ones use calculations considering only thresholds simplified (sometimes of irreversibility) and for only one resource at the same time. These calculations are generally derived from economic calculations (of type “ Rente of Hotelling ” very simplified and simplifying. Indeed, the economist Harold Hotelling posed his assumptions for the optimal management of nonrenewable resources (on human scale of time), with the example of a mining layer: for which rate/rhythm had it to be optimized to maximize the brought up to date value of its future profits: By exploiting it too quickly, the prices of coals are likely to decrease, while waiting for " trop" the owner garners less money, but preserves a revenue for his descendants or beneficiary. Hotelling gave a report on a bond between rate/rhythm of extraction and trend of the selling price. The economists of sustainable development try today to thus consider this type of calculation in an approach more ecosystemic Systémique, even and complex, by also including the Synergie S with other resources and effects in cascade or " collateral ". But in the field of the biological renewable resources (Forest for example), the unknown factors determining the future vitality of the forest are numerous.

In certain fields, Halieutic in particular, scientists has to deliver opinions which they try to support the best possible one by models, for example for the establishment of Quotas catch.

In the forest field , the evaluation of the threshold of “ overexploitation ” varies considerably according to whether one is interested only in the cubage or tonnage of wood extracted the forest, according to whether one wants the to regenerate naturally, or on the contrary by industrial plantation (with Sous-solage, Labor, Engrais and Pesticide S sometimes) or according to whether one more largely considers an exploitation also allowing perpetuation even the restoration of all the “ functions ” and all the “ ecological services ” which the forest can return, while seeking to preserve to him a Naturalité and Biodiversité sufficient to allow its ecological impact strength vis-a-vis the climatic and medical risks new.
For example in France, some (Bianco Report/ratio) estimate that the French forest under-is exploited, where others find that it misses natural reserves, of network of pieces representative of the various types of natural forests, Wetlands not exploited, senescent wood pieces, rich in “ very large wood ” and in Deadwood, etc Between the environmentalists and the sylvicultueurs it there often of the divergent appreciations of ideal threshold, or of minimal thresholds to preserve as regards pourentage of a forest put in reserve or defends some, managed in a way close to nature (Prosilva), where the wetlands would be preserved, or on the number or percentages of very large and/or very old trees which would have to be preserved, or on the degree of naturality to be preserved at timberings. In the same way the tree grower and the hunter do not have they not always the same wishes as regards balance sylvocynegetic. The forest Charte, or the step of ecocertification are places and moments of discussion or various actors can confront and negotiate their points of view, if is not to grant them. The scientific tools are of an invaluable help, but insufficient to slice when it is of alive resources and biodiversity, so much these questions are complex and the insufficient scientific data.

See too

natural Stock management
durable Management
Capital naturalness
Durability
Surpêche

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