有机肥和化学肥料配合施用对红壤肥力的影响

通过对红壤旱地长期不同施肥处理的土壤研究,发现不同的施肥处理对红壤旱地性质影响极为明显:长期施用化肥,耕作13年后,土壤活性有机质下降39.6%,在NPKS处理中,活性有机质上升16.9%,M中上升11%。长期施用有机物的处理中,土壤的微生物的数量和土壤酶的活性显著高于长期施用化学肥料的处理,由以长期单度施用化学氮肥为最低。在红壤旱地上长期施用化学肥料,使土壤严重酸化,不利于玉米的生长,肥料的长期效果为:氮肥仅增产24.9%,化学肥料配合施用的NPK处理增产率267%,NPKS处理增产率319%,M处理增产率267%,NPKM处理增产率高达367%。施用有质物还可防止土壤酸化,提高土壤的养分的有效性和肥料的利用率。

The Effects of Combined Application Organic Manure and Chemical Fertilizers on Fertility of Red Soil

The soils from different fertilizers application treatments in the long-term experiment on red soil upland were analyzed.The results showed that the effect of the treatments with different fertilizers application on soil characteristics in red soil upland was very significant. The soil labile organic matter decreased 39% after applying chemical fertilizers only for 13 years. It increased 16.9% for the NPKS treatment, and 11% for M. The amount of soil microbes and the activity of soil enzyme in the treatments with long-term application of straw and organic manure were higher significantly than that in the treatments with long-term application of chemical fertilizers, and it was the lowest in the treatment with long-term application of chemical N fertilizer only. The soil was severely acidified and the yield of corn was obviously decreased after long-term applying chemical fertilizers on red soil upland. The results of average crop biomass yields from 13 years showed that the yield of N, NPK, NPKS, M and NPKM treatment increased 24.9%, 267%, 319%, 267% and 367%, respectively, compared with control treatment. Applying straw and organic manure could prevent soil acidification, and enhance the availability of soil nutrients and utilization efficiency of fertilizers.