摘要
【目的】我国南方稻油轮作区土壤酸化趋势日趋严重,降低了作物产量。研究酸性土壤施用石灰对土壤养分及作物生长的影响,明确土壤速效养分、产量与作物养分吸收量对土壤pH的响应关系,为水田两熟区酸化土壤改良提供理论依据。【方法】2015-2018年在江西进贤县选择pH 4.5的水稻土,以熟石灰作为酸性土壤改良剂,开展田间定位试验。通过实验室模拟,计算出获得不同土壤pH情况下的熟石灰用量,试验设6个土壤pH梯度,分别为4.5、5.0、5.6、6.3、6.8、7.3,2015年匀地一年,为保证各处理土壤pH与匀地一年后实测pH基本一致,以一年为周期用熟石灰进行定量调整。【结果】(1)随着石灰用量和土壤pH的增加,土壤速效氮含量呈先增加后降低的趋势、交换性钙、交换性镁含量显著增加,土壤速效钾、有效磷含量显著降低;(2)随着石灰用量和土壤pH的增加,作物产量呈先增加后降低的趋势。土壤pH 6.4时(相当于6 145 kg·hm^-2熟石灰用量)油菜产量达到最高,较土壤pH 4.5处理增加了202.2%;土壤pH 6.8时(相当于7 474 kg·hm^-2熟石灰用量),水稻产量达到最高,较土壤pH 4.5处理增加了61.2%。油菜、水稻产量降低50%时的酸害阈值分别为4.7、4.2;(3)土壤pH显著影响作物养分吸收量。随着熟石灰用量的增加,油菜氮磷钾吸收量呈先增加后降低的趋势。2016-2018年油菜氮磷钾吸收量与不施石灰处理相比,施石灰处理平均增幅分别为59.5%-181.4%、36.2%-188.8%、65.7%-198.9%;水稻氮磷钾吸收量呈先增加后降低的趋势,在pH 6.8左右水稻氮磷钾吸收量最大。2016-2018年水稻氮磷钾吸收量与不施石灰处理相比,施石灰处理平均增幅分别为11.1%-88.6%、13.5%-68.5%、9.7%-66.1%。【结论】施用熟石灰的情况下,随着土壤pH升高,土壤速效氮、交换性钙镁等含量增加,提高了产量,促进了作物对氮磷钾养分的吸收。在本试验条件下,稻油轮作区�
【Objective】Soil acidification is becoming more and more serious, which reducing crop yield in rice-rape rotation system of southern of China. In this study, the effects of lime application on soil nutrients and crop growth in acidic soil were studied, and the response relationship between soil available nutrients, yield and crop nutrient uptake to soil pH was clarified, so as to provide theoretical basis for the improvement of acidified soil in paddy fields. 【Method】 From 2015 to 2018, the paddy field with soil pH 4.5 was selected in Jinxian county, Jiangxi province, and hydrated lime was used as acid soil modifier. Through laboratory simulation, the amount of hydrated lime under different soil pH values was calculated. Then field experiments were carried out with six soil pH gradients of pH 4.5, pH 5.0, pH 5.6, pH 6.3, pH 6.8, and pH 7.3. In 2015, in order to ensure that the pH value of the treated soil was basically consistent with the measured pH value, one year after the soil was uniformly planted, the hydrated lime was used for quantitative adjustment with a period of one year. 【Result】(1) With the amounts of lime and soil pH increase, the contents of soil available nitrogen increased first and then decreased, the content of soil exchangeable Ca2+ and exchangeable Mg^2+ increased significantly, and the content of soil available potassium and available phosphorus decreased significantly.(2) With the increase of lime contents and soil pH, crop yield first increased and then decreased. At pH 6.4(equivalent to the amount of 6 145 kg·hm^-2 hydrated lime), the yield of rape reached the highest;compared with pH 4.5, the yield increased by 202.2%. At pH 6.8(equivalent to the amount of 7 474 kg·hm^-2 hydrated lime), the rice yield reached the highest;compared with pH 4.5, the yield increased by 61.2%. When the yield was reduced by 50%, the soil pH thresholds of rape and rice were 4.7 and 4.2, respectively.(3) Soil pH significantly affected crop nutrient uptake content. With the increase of the amount of
作者
闫志浩
胡志华
王士超
槐圣昌
武红亮
王瑾瑜
邢婷婷
余喜初
李大明
卢昌艾
YAN ZhiHao;HU ZhiHua;WANG ShiChao;HUAI ShengChang;WU HongLiang;WANG JinYu;XING TingTing;YU XiChu;LI DaMing;LU ChangAi(Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Arable Land/Key Laboratory of Soil Quality,Chinese Academy of Agricultural Sciences,Beijing 100081;Jiangxi Institute of Red Soil/National Engineering and Technology Research Center for Red Soil Improvement,Nanchang 330046)
出处
《中国农业科学》
CAS
CSCD
北大核心
2019年第23期4285-4295,共11页
Scientia Agricultura Sinica
基金
国家公益性行业(农业)科研专项(201503122)
中国农业科学院基本科研业务费专项(161013201952)
