长期施肥对华北平原潮土作物产量及农田养分平衡的影响

The effects of long-term fertilization on crop yields and farmland nutrient equilibrium

研究长期不同施肥处理对华北平原潮土作物产量及农田养分平衡的影响,对指导田块尺度粮食生产的高产-高效具有重要指导意义。本研究采用长期定位试验中不同施肥处理方法分析作物产量效应及农田养分平衡。结果表明,经过7年定位施肥试验,CK、P2K2、N2K2和N2P2处理的小麦产量分别为N2P2K2处理的25.5%,34.5%,43.3%和83.2%;玉米产量分别为42.3%,52.7%,70.6%和76.2%;不施氮肥土壤氮自然供给力第1年降到59%,第2年为43%,此后稳定在40%左右;不施磷肥土壤磷自然供给力第1年降至72%,第3年为55%,之后保持在55%左右;不施钾肥土壤钾自然供给能力第1年降为93%,第3年为76%,之后基本不变;7年累计农田氮平衡状况较好的区为N2P1K2和N2P2K1,磷为N2P1K2,钾为P2K2,氮磷钾综合而言为N2P1K2;7年累计小麦、玉米对氮、磷、钾的表观利用率分别为44.3%,31.2%,53.0%和40.8%,28.9%,50.3%。综上可知,该区作物产量与施肥量有明显相关性,且氮是限制该区作物产量的首要因子,磷、钾次之;从7年累计实验来看,N2P1K2处理农田氮、磷、钾养分平衡相对较好。

Yield response and farmland nutrient equilibrium were studied in fluvo-aquic soils of the North China Plain, and the results provided a theoretical basis for high yield-high efficiency and sustainable development of grain production on a field-block scale. Fertilization treatments were used in a long-term experiment to study yield response and farmland nutrient equilibrium. The 7-year fertilization experiment to study crop responses and farmland nutrient showed that for wheat the 7-year mean yields ratio of treatments CK, P2 K2, N2K2, and N2P2 to N2P2K2 were 25.50//00, 34.5%, 43.3%, and 83.2% respectively while those for maize were 42.3%, 52.70//00, 70.6%, and 76.2%. The N supply capacity of fluvo-aquic soils in the absence of N fertilizer declined to 59% of the original in the first year investigated, fell to 43% in the second year, and then fluctuated around 40% in the following years. Without P fertilizer application, soil P capacity decreased to 72% in the first year, fell to 55% in the third year, and then fluctuated around 55%. The K supply capacity without K fertilizer addition changed from 93% in the first year to about 76% in the 7th year of the experiment. The best treatments of farmlandN equilibrium were N2P1K2 and N2P2K1, of P was N2P1K2, of K was P2K2, and of N,P,K was N2P1K2. The cumulative apparent recovery rates of N, P, K fertilizers on crops of wheat and maize were 44.3%, 31.2%, 53.0% and 40.8%, 28.9%, 50.3% respectively. There were significant correlations between amount of fertilizer and yield response. N was the main limiting factor for crop yield, then P and K. The better treatment for farmland N,P, K equilibrium was N2 PIK2.