作物产量和土壤肥力对长期养分亏缺的响应（英文）

目的]以郑州长期肥料试验为平台,研究作物产量和土壤肥力对长期养分缺乏的响应。方法]试验包括5个处理：①CK（不施化肥和有机肥）;②NP（仅施氮磷肥）;③NK（仅施氮钾肥）;④PK（仅施磷钾肥）;⑤NPK（施用氮磷钾肥）。结果]长期不施用氮肥和磷肥导致作物低产,而长期不施钾肥的NP处理与NPK处理并无显著差异,且能维持作物高产。长期不施用磷肥,土壤有效磷含量持续下降后维持在2.5 mg/kg左右.长期不施用钾肥的处理,土壤交换性钾含量维持在60mg/kg左右。前18年结果看来,土壤钾素的自然供给能力在100%左右。结论]对于潮土,氮和磷是限制小麦玉米产量、生物量及作物产量构成的最主要的两个因子,而钾素不是主要限制因子。尽管如此,若长期不施用钾肥将来也有可能出现钾素亏缺症状。

Responses of Crop Yields and Soil Fertility to Long-term Nutrient Lacking

Objective] Long-term （over 18 years） fertilization experiments were con- ducted to study the responses of crop yields and soil fertility to long-term nutrient lacking at Zhengzhou in China. Method] The present study consisted of five treat- ments： 1 CK （no fertilizer or manure）, （2） NP （nitrogen and phosphorus fertilizer applied）, 31 NK （nitrogen and potassium fertilizer applied）, 4 PK （phosphorus and potassium fertilizer applied） and ：5 NPK （nitrogen, phosphorus and potassium fertil- izer applied）. Result] Lacking of nitrogen or phosphorus led to a low yield; however, there was no significant difference in grain yields between the NP and NPK treat- ments which maintained a higher yield. Receiving no phosphorus, soil available phosphorus content declined to about 2.5 mg/kg. The concentration of soil ex- changeable potassium remained constant at a level of 60 mg/kg under the treat- ments without potassium fertilizer addition. Soil potassium spontaneous supply ca- pacity fluctuated around 100%.Conclusion] In fluvo-aquic soil, nitrogen and phos- phorus were two key limiting factors to grain yields, biomass and yield component factors of wheat and maize, while potassium was not. However, potassium defi- ciency may occur in the future if there was still no potassium fertilizer applied.