运粮湖农场土壤肥力及施肥技术的演变

Study on the Evolution of Soil Fertility and Fertilization Technology on Yunlianghu Farm of Hubei Province

通过运粮湖农场1981、1998年两次土壤普查和2007年土壤肥力调查数据以及施肥技术的改进,研究了运粮湖农场1981～2007年27年间的土壤肥力及施肥技术的演变。结果表明,土壤有机质含量持续下降,1998～2007年下降速度减缓;土壤速效磷含量持续增加;碱解氮和速效钾含量表现为"V字形"变动,1981～1998年下降,1998～2007年上升。导致土壤养分出现以上变化的原因,一是开沟排水,降低了地下水位,改变了土壤微生物的生态环境,使有机质以分解为主,同时土壤水分含量降低,使土壤钾的有效性降低;二是施肥模式和种植模式的改变,特别是2000年后实现了稻草、麦秆和棉秆全部还田,是1998～2007年土壤有机质含量下降减缓、土壤速效养分提高的重要因素。

On the base of the soil investigation in 1981 and 1998, and soil fertility survey in 2007, the analysis of soil fertility and the evolution of fertilization technology were conducted on the Yunlianghu farm in Hubei Province from 1981 to 2007. The results showed that soil organic matter content was declined during 27 years, but the rate of decline slowed from 1981 to 2007; soil available P content was increased in these years, but the changes of alkali-hydrolyzable nitrogen and available potassium contents were the V-shaped trend of decreasing from 1981 to 1998 and increasing from 1998 to 2007. That was because the ecological environment around the soil microorganisms was changed after the groundwater reducing by drainage, soil organic matter was decomposed, available potassium contents were reduced with the decrease of soil water content;the changes of fertilization and cropping patterns,especially the rice straw, wheat straw and cotton-stalk returning after 2000 were also the important factors for the slow decline of soil organic matter content and the improvement of soil available nutrient from 1998 to 2007.