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Biodiversity
https://www.youtube.com/watch?v=GK_vRtHJZu4
In simple terms, the word biodiversity refers to the variety of life on earth. It includes the diversity of genetic materials
within species, the variety of species in all taxonomic groups, and the array of communities, ecosystems, and
landscapes within which species evolve and coexist.
Species diversity
In the broadest sense, biodiversity is the sum of the variety of all living organisms at the species level. This includes
the earth's plants, animals, fungi, and even microbes that we don't see. About 1.5 million species of organisms have
been named, and there are still an estimated 10 to 100 million more that scientists have not yet described!
Genetic diversity
Within individual species, there can be a tremendous amount of genetic diversity. This genetic variability is responsible
for the different traits in species and has enabled living beings to adapt to the variety of environments that exist in the
world. It also provides the raw materials by which new species arise through evolution.
Ecosystem diversity
Ecosystem diversity is at the other end of the spectrum from genetic diversity. Ecosystems include not only the plants,
animals, and microbes that coexist at a place, but also the ways in which they interact with each other and adapt to
their physical environment.
Why is biodiversity important?
Biodiversity and its ecological processes sustain our lives and the lives of other species with which we share
the planet – plants produce the oxygen in the atmosphere, microorganisms decompose waste products and recycle
nutrients; wetlands filter pollutants and cleanse our waters; insects, birds and bats pollinate our crops. Biodiversity
provides the raw materials we need – for food, fiber, timber, medicines, fuel and other resources.
Threats to Biodiversity
In Earth's 5.5 billion year history, there have been five major "mass extinctions" recorded in the fossil record, the most
recent of which, 65 million years ago, killed the last of the true dinosaurs. Scholars believe that we are currently
experiencing extinction rates rivaling or exceeding the rates of the prehistoric mass extinctions. Although 99.9% of all
animals that once lived on Earth are now extinct, the mass destruction attributable to one species (our own) is
apparently unique in the earth's history.
Biodiversity losses can be attributed to the resource demands of our rapidly growing human population. In modern
times, the human population has increased from about 1 billion in 1900 to over 7 billion today. Like other living
beings, we use natural resources to survive, but we are far more resourceful and destructive to other life-forms than
any species previously known. As the world's human population increases, all the organisms on Earth (including
ourselves) must share the same limited resources (food, water, space). Yet there is less and less natural habitat
remaining as land is developed for human habitation and activities.
1. Habitat Degradation and Loss
2. Non-Native Invasive Species
3. Pollution
4. Overuse of Resources
5. Global Environmental Change
Introduction
The Lake Champlain Basin is a large freshwater ecosystem with a rich diversity and abundance of native fish, wildlife,
and plants. These living natural resources occupy a mosaic of interconnected aquatic and terrestrial habitats, including
broad open waters, tributaries, wetlands, forests, agricultural lands, and other areas. The natural resources of this
ecosystem provide tremendous social, recreational, economic, and environmental benefits to the Lake Champlain
Basin.
Fish, wildlife, and plants throughout the Basin are intrinsically linked in a food web, from microscopic plankton to fish,
birds, other wildlife, and plants. Phytoplankton and zooplankton are at the base of the food web and are linked to
keystone predators such as game fish and birds of prey through a complex relationship of intermediary predator and
prey species. The structure, function, and balance of the food web are closely connected to water quality, habitat
diversity, and human health. Lakes, ponds, and streams provide habitat for many different species of fish,
invertebrates, amphibians, and reptiles, some of which are threatened or endangered. Wetland areas provide critical
habitat for fish and wildlife while also improving water quality by serving as sinks for nutrients that would be delivered
to the Lake through the tributary network. Wetlands also help control flooding, protect groundwater and drinking water
supplies, reduce erosion, and protect shorelines. Rivers and streams draining upland portions of the Basin complete
the network, linking upland terrestrial and aquatic habitats to floodplains and associated wetlands and, ultimately, Lake
Champlain itself. The abundance of fish, wildlife, and plant communities within the Basin attract a wide array of
recreational users, including hunters, anglers, trappers, paddlers, hikers, and bird watchers, providing a significant
economic benefit to the regional economy. Natural species diversity is a highly valued part of the region’s natural
heritage and a critical component of the ecosystem that we all share.
The native flora and fauna of the Lake Champlain Basin have changed significantly during the last few centuries, both
in diversity and abundance. New species have been introduced to the ecosystem, others have been lost, and some
are more dominant now than historically. Some species, such as original strains of lake trout, will not likely return to
Lake Champlain in their native form. Losses of native keystone species like the lake trout, Atlantic salmon, and
American eels have a significant detrimental impact on the ecosystem, changing the natural balance of the Lake
Champlain food web. Management agencies throughout the Lake Champlain Basin are working to restore many of
these species to self-sustaining populations.
http://www.census.gov/popclock/