露地洋葱施肥、土壤养分及产量状况的分析研究

在农户调查和土壤测试相结合的基础上,分析了山东惠民县露地洋葱土壤养分状况、肥料投入及其对产量和养分平衡的影响。结果表明,施用有机肥农户占总调查户的44%,平均由有机肥带入的氮磷钾养分量分别为N 170kg hm-2、P2O5112 kg hm-2、K2O 223 kg hm-2。化肥氮、磷投入量较高,平均分别为N 458 kg hm-2和P2O5399 kg hm-2,是洋葱氮磷吸收量的4.0和6.0倍,化学钾肥不足(K2O 131 kg hm-2),占洋葱钾吸收量的55%。收获时0~30 cm土壤无机氮含量达到88 kg hm-2,O lsen-P(P)和速效钾(K)平均含量分别为25.5和104 mg kg-1。自春季返青前到收获期间,30~60 cm和60~90 cm土壤无机氮含量均有不同程度的提高,土壤氮表观损失量与氮素投入量呈显著直线相关,维持土壤氮素平衡的最大氮素供应量为290 kg hm-2。相关分析表明,无论是氮、钾化肥投入量还是各阶段土壤无机氮、速效钾含量都与洋葱产量无显著相关,而磷肥用量及0~30 cm土壤剖面O lsen-P含量与产量有显著正相关(p<0.05)。

Investigation on Fertilization, Soil Nutrition Status and Yield for Onion Production in Huimin County, Shandong Province

We investigated fertilization,nutrient balance,changes in soil available nutrient contents for onion production in 27 onion vegetable cultivation fields,from Sep.2004 to Jun.2005 in Huimin county,Shandong province,a main onion production area in China.The results showed that 44% of surveyed farmers applied organic manure and the amounts of available N,P and K nutrients in organic manure averaged to N 170 kg hm-2,P2O5112 kg hm-2 and K2O 223 kg hm-2,respectively.Besides,N,P and K from mineral fertilizer averaged to N 458 kg hm-2, P2O5 399 kg hm-2 and K2O 131 kg hm-2,which were about 4.0,6.0 and 0.55 times of the total N,P and K absorbed by onion plants,respectively.At harvest,residual mineral N(Nmin) was N 88 kg hm-2,and Olsen-P and NH4OAc-K in the 0-30cm soil layer was 25.5 and 104 mg kg-1,respectively.During the growing period from regreening stage to harvest,Nmin in the 30-90cm soil layer increased significantly,and the apparent N balance linearly increased with increasing of N supply (top-dressing fertilizer N 0-60cm soil residue N).There was no significant difference between onion yield and N and K fertilizers applied or soil Nmin and available K contents,but the amount of fertilizer P and 0-30cm soil available P contents are significantly correlated with the onion bulb yield(p<0.05).