Tags: Essay About Myself MaraEssay Writing Course TorontoPsychometric Properties Of The California Critical Thinking TestsAssignment Of Land ContractThesis On Channel Equalization Using Genetic AlgorithmCri De Coeur Romeo Dallaire EssayBest Literature ReviewHelp With Personal Statement Cv
Biogeographic principles (such as gradients in species richness associated with latitude, temperature, salinity, and water depth) or the use of indicators can supplement available biotic inventories.Global and sub-global maps of species richness, several of which are provided in the MA reports Current State and Trends and Scenarios, provide valuable pictures of the distribution of biodiversity ().Even among the larger and more mobile species, such as terrestrial vertebrates, more than one third of all species have ranges of less than 1,000 square kilometers.
Biodiversity is the foundation of ecosystem services to which human well-being is intimately linked.
No feature of Earth is more complex, dynamic, and varied than the layer of living organisms that occupy its surfaces and its seas, and no feature is experiencing more dramatic change at the hands of humans than this extraordinary, singularly unique feature of Earth.
Thus only a multidimensional assessment of biodiversity can provide insights into the relationship between changes in biodiversity and changes in ecosystem functioning and ecosystem services ().
Biodiversity includes all ecosystems—managed or unmanaged. Sometimes biodiversity is presumed to be a relevant feature of only unmanaged ecosystems, such as wildlands, nature preserves, or national parks. Managed systems—be they plantations, farms, croplands, aquaculture sites, rangelands, or even urban parks and urban ecosystems—have their own biodiversity.
More-complete biotic inventories are badly needed to correct for this deficiency ( While the data to hand are often insufficient to provide accurate pictures of the extent and distribution of all components of biodiversity, there are, nevertheless, many patterns and tools that decision-makers can use to derive useful approximations for both terrestrial and marine ecosystems.
North-temperate regions often have usable data on spatial distributions of many taxa, and some groups (such as birds, mammals, reptiles, plants, butterflies, and dragonflies) are reasonably well documented globally.
Even for the taxonomic component of biodiversity, where information is the best, considerable uncertainty remains about the true extent and changes in taxonomic diversity ().
There are many measures of biodiversity; species richness (the number of species in a given area) represents a single but important metric that is valuable as the common currency of the diversity of life—but it must be integrated with other metrics to fully capture biodiversity.
Ecological indicators are founded on much the same principles and therefore carry with them similar pros and cons ( Biodiversity is essentially everywhere, ubiquitous on Earth’s surface and in every drop of its bodies of water.
The virtual omnipresence of life on Earth is seldom appreciated because most organisms are small ( Documenting spatial patterns in biodiversity is difficult because taxonomic, functional, trophic, genetic, and other dimensions of biodiversity have been relatively poorly quantified.