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This plateau was created two million years ago by the deposition of wind-blown dust and by glacial till, called loess, which was left behind by retreating glaciers. Loess provides good agricultural soil but is highly prone to wind and water erosion. High winds and lack of vegetation contribute to the dust storms that northern China is famous for. They also account for the distinctive color of the Yellow River and Yellow Sea. Because the fine grain "loess" soils areis easily eroded, much of this landscape consists of deeply furrowed yellow hills.
Vegetation in the northern loess plateau consists of broadleaved trees and is dominated by oak. Birch, maple, aspen, willow, and linden trees can be found at higher elevations, while elm and ash trees are found at lower elevations. Steppe vegetation increases gradually to the northwest. Very little natural vegetation remains on the loess plateau, as having been replaced by agriculture centuries ago. Vegetation has been planted to help stabilize the soil and reduce erosion, but for agricultural purposes rather than to restore natural forests. While tThere are protected areas within this ecoregion, mainly in the hills less suited for farming, but unfortunately they do not include loess areas.
At the southernmost edge of this ecoregion, near the Huang He in southern Shanxi Province, is Li Shan Nature Reserve. This reserve supports warm temperate forests that provide habitat for several rare animals, including rhesus macaques, musk deer, giant salamanders, and koklass pheasants. The Lu Lian Mountains of central Shanxi Province contain the Pangquan Gou Nature Reserve, a major breeding ground for brown eared pheasants and a stopover for migratory north China larks. Black storks, Mandarin ducks, and golden eagles are all protected here. The Luya Shan, another nature reserve in the Lu Lliang Mountains, also provides an important habitat for brown eared pheasants.
Forests have been cleared here over the past few thousand years, but deforestation was particularly severe during the mid-20th century. This gradual conversion to agriculture has greatly contributed to recent erosion. For more information on this ecoregion, go to the World Wildlife Fund Scientific Report. All text by World Wildlife Fund © 2001
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