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敖汉旗位于内蒙古东部,地处燕山山脉东段努鲁尔虎山北麓,科尔沁沙地南缘。地貌类型由南到北依次为浅山丘陵、黄土丘陵、浅沙坨沼。据史料记载,400年前的敖汉是一派“沙柳浩瀚,柠条遍野,山深鹿鸣,黑林生风”的自然景观,植被十分丰茂。建国初期,全旗植被仍然较好,到处可见“天苍苍,野茫茫,风吹草低见牛羊”的景象。从六十年代初开始,由于人口剧增,“以粮为纲”政策的实施,滥垦滥牧,生态环境遭到破坏,水土流失和沙化速度明显加快。七十年代末,全旗有林面积只有
Aohan flag is located in the eastern part of Inner Mongolia, is located in the eastern section of the Yanshan Mountains north of Nuluer tiger, Horqin sandy southern margin. Topography from south to north followed by shallow hills, loess hills, shallow sand Tuo Marsh. According to historical records, 400 years ago, Aohan was one of the most beautiful landscapes in the world. The natural landscape of “Salix Willow, Handelia, Lumingshan and Black Forest” is very rich in vegetation. In the early days of the founding of the People’s Republic of China, the vegetation in the whole province was still good, and the scene of “days of darkness and vastness of fields, and the appearance of wild animals and skies” was visible everywhere. Since the early 1960s, due to the rapid population growth and the implementation of the policy of “taking grain as the key link”, the pastureland has been flooded and the ecological environment has been destroyed. The rate of soil erosion and desertification has obviously accelerated. The late seventies, the whole forest area only has