海藻肥等不同施肥处理对土壤氮素矿化及氮肥利用率的影响

Effects of Seaweed Fertilizer and Other Different Fertilization on Soil Nitrogen Mineralization and Nitrogen Use Efficiency

为了探明海藻肥及不同施肥方式的氮素养分释放规律和对作物吸收的影响,采用土壤盆栽试验,研究了等氮量施用海藻肥(S)与有机肥(M)、化肥(NPK)等不同施肥处理对菜园土壤氮矿化和春白菜氮肥利用率的影响。结果表明,不同施肥处理对土壤氮矿化量的影响差异显著。土壤矿化的无机氮含量变化主要受土壤硝态氮(NO3--N)含量高低的影响,土壤铵态氮(NH4+-N)含量始终保持较低含量水平,且变化幅度较小。各处理春白菜采收期干物重为:施化肥(NPK)>施海藻肥(S)>有机肥与海藻肥配施(MS),除有机肥与化肥配施(MNPK)外,其他处理间的干物重差异不显著。供试条件下,土壤氮素表观净矿化率和春白菜的吸氮量均为NPK>S>MS>CK,M和MNPK低于不施肥(CK)处理。氮肥利用率以NPK处理最高,达到67.7%,S和MS处理分别为46.9%和4.8%。各处理春白菜采收期干物重与吸氮量呈极显著正相关(R2=0.9213,n=18),说明作物吸氮量对产量的形成具有重要作用。S与NPK处理在相同施氮量条件下对春白菜增产作用基本相同。

In order to investigate the relationship between nitrogen nutrition release and plant uptake in seaweed fertilizer and other different fertilization,the pot culture was used to study the effects of seaweed fertilizer,organic and inorganic fertilizers with the same nitrogen content on vegetable soil nitrogen mineralization and nitrogen use efficiency of spring Chinese cabbage.The results indicated that soil mineralization capacity was significantly affected by different fertilization treatments.The mineralized nitrogen was affected nitrate content in soil.The ammonium content was kept a low level at all times,and changed smaller amplitude.The dry weight of different treatments of spring Chinese cabbage sequence was NPK〉S〉MS.There was no significantly different between all the treatments except MNPK treatment.The soil nitrogen apparent net mineralization and spring Chinese cabbage nitrogen uptake dose sequence were NPK〉S〉MS〉CK〉 M and MNPK in experiment conditions.The nitrogen use efficiency of NPK treatment was the highest in all treatments which was 67.7%.And the S and MS treatment was 46.9% and 4.8% respectively.The dry weight of spring Chinese cabbage was correlated with the nitrogen uptake content significantly（R2=0.9213,n=18）,which had important effect on yield formation of spring Chinese cabbage.The effect of S and NPK treatment on spring Chinese cabbage yield increase was almost the same at the same nitrogen utilization.