长期定位施肥对黄绵土区作物产量及养分回收率的影响

通过近30年(1981—2010年)的长期定位试验,系统研究长期施肥对黄绵土区作物产量及养分累积利用率的影响。结果表明:长期施用化肥和有机肥在显著增加小麦、油菜和胡麻3种作物产量的同时小麦产量年际间的稳定性也显著提高,化肥配施和有机肥与化肥配施的增产和稳产效果更佳;施用有机肥处理和不施用有机肥处理,氮磷配施(NP)及氮磷钾配施(NPK)的增产效应都随试验年限延长而逐渐增加,且与试验年限间呈极显著正相关关系;施用氮肥(N)、氮磷配施(NP)及氮磷钾配施(NPK)的平均增产效应分别为745、1 413 kg·hm-2和1474 kg·hm-2,有机肥的平均增产效应为983 kg·hm-2;不同施肥处理中,氮磷(NP)配合施用及氮磷钾(NPK)配施处理氮和磷的累积回收率最高,分别为44.35%、44.55%和15.11%、15.35%;施用有机肥降低了氮和磷的累积回收率,有机肥与氮磷(MNP)及有机肥与氮磷钾(MNP)配施处理氮和磷的累积回收率分别为30.41%、32.07%和9.95%、9.70%;氮磷钾(NPK)处理钾的累积回收率最高,为14.25%,同样施用有机肥显著降低了钾的累积回收率。

Effect of long-term fertilization on crop yields and nutrition accumulative recovery rates in Loessial soils region

Long-term fertilization experiment that established on Loessial soils lasted nearly for 30 years in Tianshui city of Gansu province was conducted to study the effects of long-term fertilization on crop yields and accumulative nutri-ent recovery rates .The results showed that long-term application of chemical fertilizers and manure significantly increased wheat,canola,flax grain yields and wheat yields stability between years,combined applying chemical fertilizers and or-ganic manure applying combined with chemical fertilizer resulted in higher and stable yield performance .The yields in-creased by nitrogen (N),nitrogen and phosphorus (NP),nitrogen,phosphorus and potassium (NPK)gradually in-creased with time,moreover,there were notable positive correlation between yields and times in NP,NPK,MNP and MNPK treatments.The mean wheat yields increased by N,NP and NPK were 745,1 413 kg·hm-2 and 1 474 kg·hm-2,manure application meanly increased wheat grain yield by 984 kg·hm-2 .In all treatments the highest accu-mulative nitrogen and phosphorus recovery rates appeared in NP and NPK treatments,being 44 .35%,44 .55% and 15 .1 1%,15 .35%,respectively .Manure application significantly reduced accumulative nitrogen and phosphorus recov-ery rates,MNP and MNPK treatments nitrogen and phosphorus accumulative recovery rates were 30 .41%,32 .07%and 9 .95%and 9 .70%,respectively .The highest potassium accumulative recovery rate of 14 .25%appeared in NPK treat-ment,manure application also significantly reduced potassium recovery rate .