施肥对土壤潜在养分(磷和钾)和作物产量的影响

通过 5年的田间定位试验 ,研究辽河平原土壤磷钾的自然释放速度和不同施肥制度下的肥料效应以及建立宏大养分库的过程。结果表明 ,N、P肥在下辽河平原对玉米具有极好的增产作用 ,但K肥对玉米暂时不表现增产效果 ;对大豆而言 ,P、K肥效果均很明显。不同施肥处理作物吸收养分之间的差异与产量之间的差异相似 ,但其幅度不同 ,前者明显大于后者 ,表明籽实产量的增长与养分消耗不是等比例的。豆茬土壤的供P状况要优于玉米茬 ;随着施肥年限的延长 ,残留肥料P、K进入速效养分库的量减少 ,不同元素其表现也不同。

Effect of fertilization on soil potential nutrients(P and K) and crop yields

Mid-and long-term experiment was designed to study the release rate of soil P,K and fertilizer effects under different fertilization systems at Liaohe Plain,and the process of building macro nutrients pool.The results showed that the effects of N and P fertilizer for increasing maize production were significant.But K fertilizer had not such effects.As far as soybean was concerned,P and K fertilizer all had obvious effects.The difference between quantity of nutrients and yields under different fertilization treatment was similar.However,the changed extent was different.The former was greatly higher than the latter,which indicated that the increase of grain yield and nutrients exhaustion were not proportional.The ability of P-supplication in soybean fields was better than that in maize fielels.With time running after fertilization,the quantity of residual P and K that come into available nutrients pool declined,and varied with different element.