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Ecoregions of North America, featuring the 50 United States, the District of Columbia and the five inhabited territories. The following is a list of ecoregions in the United States as identified by the World Wide Fund for Nature (WWF). The United States is a megadiverse country with a high level of endemism across a wide variety of ecosystems.
Soil that is healthy is fertile and productive. [29] But soil erosion leads to a loss of topsoil, organic matter, and nutrients; it breaks down soil structure and decreases water storage capacity, reducing fertility and water availability to plant roots. Soil erosion is, therefore, a major threat to soil biodiversity. [30]
Soils are the product of climate, organisms and topography, acting on parent (geologic) material over time. Thus the great diversity of geologic materials, geomorphic processes, climatic conditions, biotic assemblages and land surface ages in the United States is responsible for the presence of an enormous variety of mineral and organic soils.
The standard reference is The Deciduous Forest of Eastern North America. [4] The adjoining forests in Canada are generally referred to as the Mixedwood Plains Ecozone or the Great Lakes-St.Lawrence Forest Region. 32 Texas Blackland Prairies; 33 East Central Texas Plains; 34 Western Gulf Coastal Plain; 36 Ouachita Mountains; 37 Arkansas Valley
The northernmost part of the desert lies 2,000 metres (6,600 ft) above sea level, and due to high summer temperatures, not all of the fallen precipitation is fully absorbed into the soil, resulting in a high sodium concentration. [7] In other areas, mountain erosion has caused deep soils of fine particles, which allows for standing lakes.
For the 300 years following the arrival of Europeans, land was cleared, mostly for agriculture, at a rate that matched that of population growth. [7] During the 19th century, while the U.S. population tripled, the total area of cropland increased by over four times, from seventy-six million to three hundred nineteen million acres.
Located in Alaska's Denali National Park and Preserve, Denali is the tallest mountain in North America, even taller than Everest if you measure it from base to summit.At 20,310 feet above sea ...
The soil is home to a large proportion of the world's biodiversity.The links between soil organisms and soil functions are complex. The interconnectedness and complexity of this soil 'food web' means any appraisal of soil function must necessarily take into account interactions with the living communities that exist within the soil.