25年来两类植蔗土壤肥力演变及原因分析——以云南陇川农场为例

Changes and Mechenism of Soil Fertility Under Two Kinds of Sugarcane Cultivations During 25 Years——A Case Study of Longchuan Farm,Yunnan Province

通过对2007年农场土壤养分调查和1983年土壤普查资料的比较,研究了25年连续种植甘蔗后两类植蔗土壤肥力的演变及原因。结果表明:25年来旱地和水田土壤的有机质分别减少了12.65%和25%;全N旱地的变化不大,水田比1983年减少了1.42%;碱解N旱地增加了1.53%,水田减少了22.65%;速效P旱地和水田都比1983年有所增加,增加幅度为旱地大于水田,其中旱地和水田分别增加了95.02%和6.02%;速效K旱地比1983年增加了26.36%,但水田减少了47.28%。结合糖厂历史单产、产糖率和农场蔗叶还田的情况,研究得出蔗叶还田能够持续培肥蔗区土壤养分,是蔗区甘蔗持续高产的主要原因。

The changes and mechanism of soil fertility under two kinds of sugarcane cultivations during 25a were studied at Longchuan farm based on the data obtained from the surveys in 1983 and 2007. The results showed as follows： soil organic matter contents in dry land and paddy field reduced by 12.65% and 25% respectivelY, total nitrogen content changed little in dry land but reduced by 1.42% in paddy field, available N increased by 1.53% in dry land but reduced by 22.65% in paddy field, available P increased by 95.02% and 6.02% respectively in dry land and paddy field, available K increased by 26.36% in dry land but reduced by 4Z28% in paddy field. The data of sugar yield and sugar recovered ratio proved that sugarcane leaf returning to field could improve soil fertility sustainably, which was attributed to for the continuous high sugar yield in studied region.