长期不施化学钾肥对陇东旱塬作物产量及土壤速效钾含量的影响  

Effect of different long-term fertilizations without chemical potassium on crop yield and soil available potassium contents in Loess Plateau of Eastern Gansu

作　　者：王婷[1] 周海燕 李利利 丁宁平 俄胜哲[1] 车宗贤[1] 

机构地区：[1]甘肃省农业科学院土壤肥料与节水农业研究所,甘肃兰州730070 [2]甘肃省平凉市农业科学研究所,甘肃平凉744000

出　　处：《中国土壤与肥料》2015年第5期44-49,共6页Soil and Fertilizer Sciences in China

基　　金：甘肃省农业科学院创新专项"创新基地长期肥料定位试验科研协作网建设(2013GAAS12)";公益性行业(农业)科研专项"粮食主产区土壤肥力演变与培肥技术研究与示范(201203030)"

摘　　要：依托1978年开始的定位试验,研究了陇东旱塬长期不施化学钾肥条件下不同施肥制度对作物产量的影响以及麦田不同时期土壤速效钾在剖面的分布特征。试验包括6个处理：不施肥、单施氮肥、氮磷肥配施、秸秆与氮磷肥配施、单施有机肥、氮磷与有机肥配施。结果表明,与习惯氮磷配施比较,氮磷与有机肥配施大幅提高了作物总产22.57%,秸秆与氮磷配施也有增产效果,单施有机肥产量接近。施用有机肥提高了0~40 cm土层速效钾含量,秸秆还田可以缓解土壤钾素消耗,但不能抵消作物携出的钾素,单施氮肥、氮磷肥配施导致土壤速效钾严重耗竭。无有机肥投入各处理在孕穗期表层土壤速效钾含量较低,在夏闲期则中层土壤相对较低。与试验前初始值相比,施用有机肥处理0~20 cm土层速效钾有较大提高,秸秆还田以及其他各处理则明显降低。仅施氮肥或仅氮磷配施处理36年后土壤速效钾含量接近黄土高原大田作物钾素临界值,应及时考虑对土壤的钾素补充。The crop yield and soil available potassium（ K） in 0 ~ 100 cm soil profile under different long-term fertilizations without chemical potassium in Loess Plateau of Eastern Gansu were investigated at 2 stages（ wheat booting,summer fallow）based on an experiment started from 1978. Six treatments were included,i. e.,no fertilizer（ CK）,nitrogen only（ N）,nitrogen and phosphorous（ NP）,nitrogen and phosphorous combined with straw return（ SNP）,manure only（ M）,nitrogen and phosphorous combined with manure（ MNP）. The results showed that,compared with the NP treatment,the MNP treatment increased the yield obviously by 22. 57%,yield improvement was also observed in the SNP treatment,and the yield in the M treatment was quite close. Manure application improved the soil available K in 0 ~ 40 cm layers significantly. Straw return mitigated but didn＇t offset the K removal by crop production. The applications of chemical N or NP only resulted in serious exhaustions of soil available K. The soil available K contents in top level in the treatments without manure were lower at the wheat booting stage than those in the lower soil levels,while the soil available K contents in the middle layers were lower at the summer fallow stage. Compared with the initial values before the long-term experiment started,the manure application enhanced the soil available K significantly,while other treatments including SNP decreased it greatly. Values close to the threshold for soil available K in Loess Plateau were found in the treatments with chemical N or NP after 36 years,which suggesting that K supply should be paid attention hereafter in Eastern Gansu.

关 键 词：不施化学钾肥 长期定位试验 土壤速效钾 陇东旱塬 

分 类 号：S147.2[农业科学—肥料学]