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漏沙土是“三北”防护林区重要的耕作土壤,也是沙漠边缘区主要低产土壤类型之一,其形成与整地方法不当、新开垦后耕种年限短土壤熟化程度低、风沙侵袭频繁等因素有关。通过对甘肃张掖地区漏沙土的剖面理化性质分析可以看出,耕作层有机质含量低至0.78%,全剖面各类土壤养分含量极低;除耕作层具有微弱团粒结构外,以下土层质地明显偏沙,多为粒状结构,阳离子代换量仅不到6.0 meq/100g土,土壤保肥保水能力很差。应根据当地自然条件,考虑林带的位置、结构和树种的选择,注重农田防护林和防风固沙林的营造与管护;发展豆科绿肥作物,实行草田轮作,提高土壤养分含量;兴修水利,调整灌溉制度,推广喷灌、滴灌技术,减少水分的淋失;深耕整地,选用耐旱抗风沙的作物品种,调整播种期以避开风季,多施土粪加厚有效土层,巧施氮、磷化肥和微肥,防止作物因生长后期脱肥而减产。
Lost sand is one of the important tillage soils in the “Three Norths” shelter belt and one of the main low-yielding soil types in the marginal zone of the desert. Its formation and land preparation methods are improper. After the new land reclamation, the soil aging degree is short, and frequent sandstorm infiltration and other factors related. Through the physical and chemical properties analysis of the sand-loam in Zhangye area of Gansu, we can see that the content of organic matter in the tillage layer is as low as 0.78%, and the content of nutrient in the soil is very low in all sections. The tillage layer has the weak aggregate structure, Sand, mostly granular structure, the amount of cation substitution is only less than 6.0 meq / 100g soil, soil fertilizer and water retention capacity is poor. We should focus on the construction and management of farmland shelterbelts and windbreaks and sand-fixing forests in light of the local natural conditions, taking into account the choice of location, structure and tree species of forest belts. We should develop leguminous green manure crops to promote grass rotation and soil nutrient content; , Promote sprinkler irrigation, drip irrigation technology, reduce the leaching of water; deep plowing the whole area, the selection of drought-resistant windbreak of crop varieties, sowing season to adjust to avoid the windy season, more effective application of soil manure thickened soil, clever nitrogen and phosphorus fertilizer And trace fertilizers to prevent crops from yielding due to late-stage de-fertilization.