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在整个风沙草原地带的风蚀波状高原地区和草原地带的陕蒙盖沙丘陵地区,均可采取乔、灌、草结合的措施加以治理。现对比一下乔、灌、草各自所具有的特点: 乔木,根系水平分布在10—20厘米以下,成林郁闭前固土能力弱,防护效果差;成林后,防护效果增强;成材后,经济价值大。但乔木从成林到起防护效果的过程周期较长。 灌木,生长都闭快,易繁殖,见效快,收益快;灌木改良土壤,增加肥力,适性强,能在干旱瘠薄的沙漠和冲刷裸露母质砒砂石上生长。许多灌木在年降雨量只有几十毫米以及地下水很深和苦水区仍能正常生长。种植灌木又可以达到土壤养份(肥力)的恢复和积蓄。象酸刺,它虽不是豆科植物,却也有根瘤菌,能很快地增加土壤肥力;生长六年的酸刺地,土壤有机质含量可提高到2.15％,含氮量增加0.118％,比当年最好耕地的含量高一倍。柠条,每1000公斤干枝叶中含氮、磷、钾分别为29公斤,5.5公斤和14.3公
Throughout the wind-blown grassland wind-induced wave plateau area and steppe hilly area of Shaanxi and Mongolia Geisha, can take the combination of measures such as Qiao, irrigation and grass to be governed. Now compare the characteristics of Joe, irrigation, grass each has: trees, root level distribution in the 10-20 cm below the forest canopy closed before weak soil protection effect is poor; after the forest, the protective effect is enhanced; , Economic value. However, trees from the forest to the protective effect of the longer period of the process. Shrubs grow fast, easy to reproduce, quick, quick returns; shrubs improve the soil, increase fertility, adaptability, can be in the arid barren desert and scouring bare parent material 砒 gravel growth. Many shrubs grow normally only in the midst of an annual rainfall of only tens of millimeters and deep groundwater and in the bitter waters. Planting shrubs, in turn, achieves the recovery and savings of soil nutrients (fertility). Like acid thorns, although it is not a legume, but also Rhizobium, can quickly increase soil fertility; growth of acid for six years, soil organic matter content can be increased to 2.15%, nitrogen content increased 0.118% The best content of arable land doubles. Caragana, nitrogen, phosphorus, potassium per 1000 kg of dried leaves are 29 kg, 5.5 kg and 14.3 kg