摘要： 为了了解长期施肥对黑土玉米田土壤钾素养分动态平衡的影响，以黑土玉米田长期定位施肥试验（1984-2015年）为平台，运用振荡法研究了不同施肥对玉米田黑土钾素Q/I曲线特性、供钾容量、供钾强度和钾潜在缓冲容量的影响。结果表明，长期不同施肥处理黑土钾素的容量-强度（Q/I）曲线与典型的Q/I曲线相类似；不同施肥处理间Q/I曲线呈现出类似的形状，都是由曲线和直线两部分组成。施肥可以增加玉米田黑土中供钾容量（-ΔK₀）和供钾强度（ARe_K），降低玉米田黑土钾潜在缓冲容量（PBC_K），氮磷钾配施高量秸秆的处理（NPK+S_0.5）黑土-ΔK₀值最高，为0.167 9 cmol/kg，ARe_K值也是在NPK+S_0.5处理下最高，为1.718 5×10^-3（cmol/kg）^-1/2；然而，PBC_K值最小，为97.7（mg/kg）/（cmol/kg）^1/2，施用钾肥和秸秆对增加玉米田土壤中-ΔK₀值和ARe_K值、降低PBC_K值效果较为明显。相关性分析表明，黑土-ΔK₀值和ARe_K值与土壤有机质、全氮、全磷、全钾、速效钾含量存在着极显著的正相关（P <0.01），而PBC_K值恰好相反。总体而言，化肥配施秸秆对土壤的理化性质及-ΔK₀值、ARe_K值和PBC_K值都有较大的影响，既可以增加土壤养分，又可以增加土壤供钾能力。因此，合理施肥有利于提高土壤钾素营养的供应能力，提高作物产量和品质。

关键词: 长期施肥, 玉米田土壤, Q/I特性, 供钾能力

Abstract: In order to understand the effect of long-term fertilization on the dynamic balance of potassium nutrients in black soil corn fields. We based on the long-term fertilization experiment (1984-2015) in black soil corn field,the effects of different fertilization treatments on the characteristics of Q/I curve and the parameters (potassium supply capacity,potassium supply potential and potassium buffer capacity) of black soil in maize field were studied. The results showed that long-term different fertilizer treatments of black soil potassium Q/I curve and typical Q/I curve was similar. Q/I curve among different fertilizer treatments presented a similar shape. It consisted of two parts:curve and straight line. Fertilization could increase in the black soil-ΔK₀ value and ARe_K value,reduced the black earth PBC_K value,treatment of NPK with high straw content (NPK+S_0.5) black soil-ΔK₀ value of up to 0.167 9 cmol/kg,ARe_K value was also the highest under NPK+S_0.5 treatment 1.718 5×10^-3(cmol/kg)^-1/2.However,the PBC_K value was the smallest,which was 97.7 (mg/kg)/(cmol/kg)^1/2. Applying potassium fertilizer and straw was more effective in increasing the-ΔK₀ and ARe_K values and decreasing the PBC_K value in the corn field soil. The correlation analysis showed that there was a significantly positive correlation between black soil-ΔK₀ and ARe_K values and soil organic matter,total nitrogen,total phosphorus,total potassium,and available potassium content (P <0.01),and PBC_K values were exactly the opposite. In general,chemical fertilizers combined with straw had a great influence on the physicochemical properties of the soil and the-ΔK₀ value,ARe_K value and PBC_K value. It could not only increase soil nutrients,but also increase soil potassium supply capacity. Therefore,reasonable fertilization will help increase the supply capacity of soil potassium nutrition and increase crop yield and quality.

Key words: Long-term fertilization, Corn field soil, Q/I characteristics, Potassium supply capacity

中图分类号: 

• S153.6

• S143.3