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为什么要营造水土保持林我国许多山区和丘陵区,出于森林被破坏,山坡被滥垦,很多本来是山青水秀的地区,现在却成了水竭石露的光山秃岭。据统计,我国森林面积只占国土总面积的7.9%左右,而且分布很不均匀。土壤因为缺乏植物庇护,水土长期流失,而且情况愈趋严重。据初步估计,全国水土流失面积约达150多万平方公里,约占国土总面积的六分之一。其中以黄河中游黄土高原地区的情况最为严重,到处沟壑密布,耕地日益减少。平均每年每
Why to Create Soil and Water Conservation Forests Many mountainous and hilly areas in China have been destroyed by forests and hillsides have been inundated. Many areas that were originally mountains and rivers are now Guangshan Baling. According to statistics, the forest area in China only accounts for 7.9% of the total land area, and the distribution is very uneven. Due to lack of plant protection, the soil is lost for a long period of time and the situation becomes more serious. According to preliminary estimates, the area of soil erosion in the country has reached more than 1.5 million square kilometers, accounting for about one-sixth of the country’s total land area. Among them, the situation in the Loess Plateau in the middle reaches of the Yellow River is the most serious. Gully is everywhere and the amount of cultivated land is decreasing. Average each year