不同施肥对黑土有机无机复合及腐殖质结合形态的影响

Effect of various fertilization on the organo-mineral complexation and the combined forms of humus of phaeozem

利用长期定位试验研究了施肥对黑土有机无机复合及腐殖质结合形态的影响。试验设不施肥(CK)、单施化肥(NPK)、常量有机肥与化肥配施(NPKM1)、1.5倍有机肥与化肥配施(NPKM2)和秸秆与化肥配施(NPKS)5个处理。结果表明:长期合理施用化肥能使土壤有机碳、重组有机碳的含量和原土复合量趋于增加;有机无机配施能使土壤有机碳、重组有机碳、原土复合量、土壤追加复合量及追加复合度增加,而原土复合度降低,增加有机肥用量可以降低土壤追加复合度。施肥能促进土壤中各种结合形态的腐殖质绝对含量和土壤松/稳和松/紧比值增加,但以松结合态腐殖质增加的较多。不同处理中高用量的有机肥处理(NPKM2)效果更明显。有机无机配施有利于改善土壤有机无机复合状况,增强土壤对养分的供贮、调控能力,提高土壤肥力水平。

A long-term field experiment was carried out to study the effect of fertilization on the organo-mineral complexation and the combined forms of humus of phaeozem in Jilin Province, China. The experiment included five treatments ： zero fertilization （CK） , chemical fertilizers alone （NPK）, combined application of general organic manure rate and chemical fertilizers （NPKM1）, com- bined application of 1.5 multiples rate organic manure and chemical fertilizers （ NPKM2 ） , and combined application of straw manure and chemical fertilizers （NPKS）. The results showed that the contents of organic carbon in soil and heavy fraction and the quantity of organo-mineral complexation tended to increase under a long-term of the treatment of chemical fertilizers alone. The combined application of organic manure and inorganic fertilizer could increase the contents of organic carbon in soil and heavy fraction and the quantity of organo-mineral complexation and the quantity of additional organo-mineral complexation and the degree of additional organo-mineral complexation, but could decrease the degree of organo-mineral complexation. The increased dosage of organic manure could decrease the degree of additional organo-mineral complexation. Fertilization could increase the contents of various combined humus in heavy-fraction and the ratios of loosely to stably combined humus and loosely to tightly combined humus, especially loosely combined humus. The effects of combined application of high rate manure and inorganic fertilizers were the best in different treatments. The combined application of organic manure and inorganic fertilizers could improve the status of the organo-mineral complexation, enhance the holding capability of nutrient in soil and therefore increase soil fertility.