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以国家褐潮土16 a的长期肥料试验为平台(北京昌平),研究长期不同施肥对耕层土壤水稳定性团聚体及其有机碳的影响。主要研究结果:与耕种农田土壤相比,长期撂荒(CK0)可以提高水稳定性大团聚体的含量及其有机碳含量和储量。而农田耕作后,破坏了水稳性大团聚体,相应地增加水稳性微团聚体的含量。与长期不施肥种植作物(CK)相比,长期施氮磷钾肥(NPK)、氮磷钾配施有机肥(NPKM)和氮磷钾秸秆还田(NPKS)处理对水稳性团聚体数量分布和平均重量直径(MWD)有显著影响,其中对>2mm和0.25 2mm水稳性大团聚体的促进作用最明显,说明施肥处理增加的新碳主要向0.25 2mm和>2mm团聚体富集。在不同水平水稳性团聚体中,>2mm和0.25 2mm两个级别的水稳性大团聚体有机碳的含量显著高于0.0530.25mm和<0.053mm水稳性微团聚体。化肥与有机肥配施(NPKM)处理可提高水稳性大团聚体含量,改善土壤团聚体的结构。长期小麦-玉米→小麦-大豆复种轮作并施氮磷钾化肥的处理(NPKF)各级团聚体中有机碳的含量高于长期小麦-玉米轮作并施氮磷钾化肥的处理(NPK)。
The long-term fertilizers test of 16-year brown soil in China (Changping, Beijing) was used to study the effects of long-term fertilization on soil water-stable aggregates and organic carbon in topsoil. Main findings: Long-term fallowing (CK0) can increase the content of water-stable macroaggregates and their organic carbon content and reserves compared to cultivated farmland soil. After farming, the water-stable macroaggregates were destroyed, increasing the content of water-stable microaggregates accordingly. Compared with long-term non-fertilizing cropping (CK), long-term application of NPK, NPKM and NPKS treatment had no significant effect on the distribution of water-stable aggregates (MWD). Among them, the promotion effect on> 2mm and 0.252mm water-stable macromolecules was the most obvious, which indicated that the new carbon added by fertilization treatment was mainly enriched to 0.252mm and> 2mm aggregates. At different levels of water-stable aggregates, the contents of organic carbon in water-stable macroaggregates> 2 mm and 0.25 2 mm were significantly higher than 0.0530.25 mm and <0.053 mm water-stable microaggregates. Fertilizer and organic fertilizer (NPKM) treatment can increase the content of water-stable large aggregates and improve the structure of soil aggregates. The content of organic carbon in aggregates of long-term wheat-corn-wheat-soybean multiple crop rotation with N, P, K fertilizers was higher than NPK fertilization (NPK) at long-term wheat-corn rotation.