摘要
【目的】探索马铃薯种植过程中稻草覆盖还田模式下稻草N、P、K释放和土壤N、P、K养分平衡的特征。【方法】采用盆栽试验的方法,对稻草覆盖还田后的腐解速率及养分释放状况进行研究。【结果】稻草覆盖还田82 d后,其C、P含量变化较小,K含量降低93.96%,而N含量却提高了49.22%;覆盖稻草可为土壤提供大量养分且以K居多,每覆盖还田100 kg稻草可为马铃薯生长提供N 0.42 kg、P 0.14 kg(P2O5)和K 1.70 kg(K2O);稻草腐解率为70.87%;各养分累积释放率表现为:K>C>P>N,C、N和P累积释放率分别为71.89%、56.85%和68.75%,K累积释放率最高,为98.22%。覆盖稻草和施用钾肥对土壤K平衡影响较大,不施钾肥和稻草土壤的K亏缺达163.80 kg/hm2,覆盖稻草或施用钾肥均可有效降低土壤钾素亏缺量,稻草与钾肥配合施用可使土壤K收支平衡,甚至盈余。【结论】在稻草覆盖还田情况下,可适当减少钾肥用量,以降低生产成本,缓解我国钾肥资源匮乏的困境。
【Objective】To study the characteristics of nitrogen(N),phosphorus(P)and potassium(K)nutrient release and soil N,P,K nutrient balance under straw mulching pattern during potato planting process.【Method】We studied the decomposition rate and nutrient release status of mulching straw using pot experiment.【Result】Straw carbon(C)and P contents changed slightly after mulching for 82 days,while K content decreased by 93.96%,and N content increased by 49.22%.The mulching straw provided a large amount of nutrients(especially K)with 100 kg mulching straw contributing 0.42 kg N,0.14 kg P(P2O5),and 1.70 kg K(K2O)to soil used for potato growth.Straw decomposition rate was 70.87%.The nutrient accumulative release rates were performed as:K(98.22%)>C(71.89%)>P(68.75%)>N(56.85%).Straw mulching and K fertilization largely affected soil K balance.The K deficient amount was 163.80 kg/hm2 without straw mulching and K fertilizer application.K deficient amount was effectively reduced by straw mulching and K fertilization,and even K had surplus with combined application of straw and K fertilizer.【Conclusion】The straw mulching pattern can reduce K fertilizer application amount and production cost,and relieve the dilemma of K fertilizer resource deficiency in China.
作者
张新明
程根
徐鹏举
曹先维
ZHANG Xinming;CHENG Gen;XU Pengju;CAO Xianwei(College of Natural Resources and Environment,South China Agricultural University,Guangzhou 510642,China;Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,China;Huidong Agricultural Technical Extension Center,Huizhou 516300,China;College of Horticulture,South China Agricultural University,Guangzhou 510642,China)
出处
《华南农业大学学报》
CAS
CSCD
北大核心
2019年第6期59-66,共8页
Journal of South China Agricultural University
基金
国家重点研发计划项目(2018YFD0200801)
农业部“现代农业产业(马铃薯)技术体系”团队项目(CARS-09-ES18)
关键词
马铃薯
养分释放
养分平衡
稻草覆盖还田
腐解
potato
nutrient release
nutrient balance
straw mulching
decomposition
