施肥方式对崩岗洪积扇土壤养分改良研究

Soil Nutrient Amelioration in Collaping Gully Alluvial Fan Under Fertilizations

中国南方花岗岩地区崩岗侵蚀给农业生产带来了严重的威胁,尤其是崩岗侵蚀产生的大量泥沙沉积,导致农田土壤质量恶化以及农作物大量减产。为探索崩岗洪积扇农田土壤改良的有效方式,本研究通过采集通城县崩岗洪积扇土壤进行油菜盆栽实验,研究不施肥(CK)和施化肥、塘泥、塘泥+化肥与生物肥等5个处理对土壤养分改良的效果,并利用灰色关联分析方法评价土壤肥力,结合油菜产量,经对比得出最佳的施肥方式。结果表明:与CK相比,其他处理的土壤有机质、阳离子交换量、氮磷钾含量有明显的提高,油菜产量也有显著的增加;Pearson相关分析表明,各养分指标与产量间呈正相关。土壤肥力按关联度排序为:塘泥+化肥>塘泥>生物肥>化肥>不施肥,塘泥+化肥处理的土壤质量等级为Ⅱ级(良),是最佳的施肥方式;CK的土壤最为贫瘠,土壤质量等级为Ⅴ级(极差)。本研究为崩岗洪积扇农田质量恢复提供了科学依据,对于农业生产有重要的实践意义。

Collapsing gully erosion seriously threatens agricultural production in southern China. Great amount of sediment form collapsing gully would result in soil quality deterioration and crop reduction. To explore the effective improvement manner of alluvial fan soil, the soil in Tongcheng Couty was collected and five fertilization treatments（no fertilizer（CK）, chemical fertilizer, mixed with pond scum, pond scum chemical fertilizer and biofertilizer）were conducted to study the effects of different soil improvement measures on the soil properties and crop yield, and to evaluate the soil fertility by using the gray correlation analysis method, then to find the optimum way of fertilization. The results showed that compared to CK, the pond scum and pond scum chemical fertilizer treatments significantly improved the soil organic matter, cation exchange capacity and NPK contents, also the crop yields significantly increased. Pearson correlation analyses showed that the nutrient indicators were positively correlated with the crop yield. The results also demonstrated that fertility evaluation results were as followed： pond scum chemical fertilizerpond scumbio-fertilizerchemical fertilizerno fertilizer（CK）. The quality grade of the soil treated by pond scum chemical fertilizer was Ⅱ grade（good）, and the soil without fertilization（CK） was Ⅴgrade（poor）. This suggests that the pond scum chemical fertilizer treatment was the optimum fertilization. Results from the present study may broaden our knowledge of fertilization effects on field soils and provide solutions to the amelioration and utilization of farmlands.