不同土地利用方式对黑土农田酸化的影响

以中国科学院海伦农业生态实验站黑土区的农田长期定位试验土壤（1989—2004）为研究对象，研究了长期不同土地利用方式对农田黑土pH值的影响。研究结果表明，长期连作促进土壤酸化，不同作物对土壤酸化的能力不同，玉米〉大豆〉小麦；降雨量影响土壤pH值，降雨促进土壤pH值升高，干旱降低pH值，wj〉w3〉w2〉W1；施肥种类同样也影响土壤pH值，长期不施肥料（CK），土壤pH值基本保持稳定，而施用大量化肥（NPK）土壤酸化强度很大，而配施有机肥（NPK＋OM）或与秸秆还田相结合（NPK＋SR），可以缓解施用化肥引起的土壤酸化。因此，通过调控的土地利用方式，可以稳定土壤pH值，保持土壤的持续生产力。图2，表2，参12。

The Effects of Different Land-use Types on Farm Black Soil Acidification

To study the effect of various land-use types on pH in black soil,the long-term experimented agricultural soil,which located in Hailun Agricultural Ecological Experimental Station,was taken as a research example.Long-term continuous cropping induced soil acidification.However,plant species had different effect,the order was maize>soybean>wheat.The content of water also affected pH in soil, pH in soil increased as water content increased,and decreased as water content decreased.Fertilizer type affected pH in soil.The pH was kept in stable in no fertilizer apply treatment.Chemical fertilizer increased soil acidification,however,soil acidification was reduced with organic fertilizer application.All these suggested that soil pH can be stable with various land-use types and sustainable productivity can be maintained.