田间土壤生物体氮的影响因子研究

在杨凌中等肥力红油土上进行大田试验，研究土壤生物体氮的变化及影响因子。试验结果表明，不同季节土壤生物体氮含量不同，秋季和春季较高，初冬居中，严冬最低，这种变化规律与土壤温度和水分含量变化相一致。施用氮肥和有机肥能显著增加生物体氮。不施氮时，种植油菜和小麦田块土壤中生物体氮显著低于休闲土壤，而施氮后，则高于休闲土壤；种植豌豆不同于其它两种作物，不施氮时，生物体氮仍然和休闲土壤持平，这表明在种植条件下，施用氮肥或种植豆科作物对维持土壤生物体氮库具有重要意义。土壤生物体氮不仅耕层远远高于下层，而且根际土壤显著大于非根际土壤。

Studies on Influencing Factors of Organism-nitrogen in the Field Soil

Influencing factors of organism-nitrogen in the field s oil were studied by the field experiment in moderate fertilizer red-soil of Yan gling. The results showed the contents of organism-nitrogen varied under differ ent seasons,in autumn and spring were higher,in early winter was moderate and in severe winter was the lowest, which conform to the regulation of water content and soil temperature. Nitrogen manure and organic manure had positive influence s on rape and wheat, but they don't comply with plea. It also indicated that und er planting, application of nitrogen fertilizer or planting of bean section crop s had great significance for organism-nitrogen storeroom in soil.The organism- nitrogen in cultivate layer and root-border soil were far higher than those of underlayer and no root-border soil.