温室滴灌条件下施用鸡粪和磷肥对土壤磷素的影响

Effect of Applying Chicken Manure and Phosphate Fertilizer on Soil Phosphorus Under Drip Irrigation in Greenhouse

【目的】针对温室土壤磷素积累的问题,定位研究滴灌条件下施用鸡粪和磷肥对土壤磷素积累的影响。【方法】以中国华北平原日光温室为研究对象,采用滴灌方式灌溉,设置不施肥(CK)、单施磷肥(P1)、单施鸡粪(OM)、鸡粪和减量磷肥配合施用(OM+P1)、鸡粪和习惯量磷肥配合施用(OM+P2)共5个处理,研究不同施肥方式对黄瓜土壤无机磷各形态的转化积累、不同生育时期在土壤垂直剖面的运移分布及其有效性的影响。【结果】鸡粪和磷肥配施显著增加了土壤中的全磷、有效磷(Olsen-P)及无机磷的积累和残留。在0—20 cm土层中,全磷含量随着黄瓜生育时期的推进呈下降趋势,苗期最高,产瓜末期最低。不同施肥处理下,土壤全磷含量明显不同,各生育时期顺序均为OM+P2处理>OM+P1处理>P1处理>OM处理>CK处理;土壤剖面各层次有效磷含量差异很大,苗期0—20 cm土层有效磷含量范围为44.43—86.08 mg·kg^-1,20—40 cm土层含量范围为6.51—10.05 mg·kg^-1,40 cm以下土层黄瓜各个生育时期有效磷含量差异很小。在温室滴灌条件下水分对磷的运移影响较小,土壤有效磷主要集中在0—20 cm土层,各生育时期0—20 cm土层有效磷占土壤剖面0—100 cm土层有效磷的68.76%—87.78%。与CK相比,其他施肥处理均提高了有效磷占全磷的比重,提高范围为1.23%—2.47%。0—20 cm土层中不同形态无机磷的含量为Ca10-P>Ca8-P>O-P>Ca2-P>Al-P>Fe-P,其中,Ca-P所占比例最大,为79.55%—83.35%。随着磷肥用量增加,磷的积累量也增加,Ca8-P、Ca2-P、Al-P、Fe-P和Ca10-P含量均比不施磷的处理显著提高,以Ca8-P增加最多,其次是Ca2-P、Al-P和Fe-P;磷肥施入土壤后很快会经由Ca2-P转化为Ca8-P,而以缓效态累积在土壤中,各形态无机磷中以Ca8-P积累最多,Al-P和Fe-P也有一定量的积累。【结论】传统过量施肥造成磷素以Ca8-P、Al-P和Fe-P等形态残留于土壤中,造成了土壤磷素的积累和磷肥的浪费。在30000 kg·hm^-2鸡粪的基础上增施磷肥并无显著增产效应,却显著增加了土壤磷素的残留积累量。如果只施鸡粪,用量不宜超过30000 kg·hm^-2;如果配施无机磷肥,则鸡粪减量,且无机磷肥在300 kg·hm^-2的基础上减量,具体施肥量及配施比例有待进一步研究探讨。

【Objective】Aiming at the problem of phosphorous accumulation in greenhouse soil,the effects of applying chicken manure and phosphorus fertilizer on phosphorus accumulation in soil under drip irrigation were studied.【Method】The solar greenhouse in North China Plain using drip irrigation was taken as research object.Five treatments were designed,including no fertilizer(CK),single phosphate(P1),single chicken manure(OM),chicken manure and reduced phosphate fertilization(OM+P1),chicken manure and habitual phosphate fertilization(OM+P2),to reveal the enrichment and transformation,migration and distribution in vertical section of soil at different growth stages and availability of inorganic phosphate form in soil.【Result】The results showed that the combination of chicken manure and phosphate fertilizer significantly increased the accumulation and residue of total phosphorus,available phosphorus(Olsen-P)and inorganic phosphorus in soil.In the soil layer of 0-20 cm,total phosphorus content decreased with the development of cucumber growth period,highest in seeding stage and lowest in late fruiting stage period.Under different fertilization treatments,total phosphorus contents were significantly different,and the sequence of each growth period was OM+P2 treatment>OM+P1 treatment>P1 treatment>OM treatment>CK treatment.The Olsen-P contents at different levels in the soil profile varied greatly.In seedling stage,the range was 44.43-86.08 mg·kg^-1 at soil of 0-20 cm,6.51-10.05 mg·kg^-1 at soil of 20-40 cm,and there was very little variability in soil layer lower than 40 cm.The effect of water on the movement of phosphorus was slight under the condition of drip irrigation in greenhouse.So Olsen-P mainly concentrated in the soil layer of 0-20 cm,which accounted for 68.76-87.78%of the available phosphorus in soil profile of 0-100 cm in each growth period.Compared with CK,the other treatments increased the proportion of Olsen-P in total phosphorus by 1.23%-2.47%.The sequence of inorganic phosphorus content of different forms in soil layer of 0-20 cm was Ca10-P>Ca8-P>O-P>Ca2-P>Al-P>Fe-P,among which,the proportion of Ca-P was the highest(79.55%-83.35%).As the amount of phosphorus fertilizer increased,so did the accumulation of phosphorus.The contents of Ca8-P,Ca2-P,Al-P,Fe-P and Ca10-P under fertilization treatments were all significantly higher than that under CK,with Ca8-P increased the most,followed sequentially by Ca2-P,Al-P and Fe-P.Phosphate fertilizer would be converted into Ca8-P through Ca2-P soon after it was applied into the soil,which accumulated in the soil in a slow manner.Among all forms of inorganic phosphorus,Ca8-P accumulated the most,Al-P and Fe-P also accumulated to a certain extent.【Conclusion】Traditional excessive fertilization caused phosphorus remaining in the soil in the forms of Ca8-P,Al-P and Fe-P,resulting in the accumulation of soil phosphorus and waste of phosphorus fertilizer.On the basis of 30,000 kg·hm^-2 chicken manure,adding phosphate fertilizer had no significant effect on increasing yield but obviously increased the residual accumulation of phosphorus.If only chicken manure was applied,the dosage should not exceed 30000 kg·hm^-2.If inorganic phosphate fertilizer was combined,the amount of chicken manure should be reduced,while the inorganic phosphate fertilizer rate should be less than 300 kg·hm^-2.The specific amount and proportion of fertilizer application need further study and discussion.