生物炭对双季水稻产量、养分吸收和土壤性状的残留效应

生物炭对改良酸性土壤质量和提高作物产量具有重要作用。本研究以常规稻中嘉早17(早稻)和杂交稻五优308(晚稻)为供试品种,于2015年开始设置不施生物炭(C0)和一次性施用生物炭20 t/hm^2(C20)处理,以阐明施用生物炭3年后对双季稻产量、养分吸收和土壤性状的残留效应。结果表明,与C0处理相比,C20处理显著提高双季早稻产量,但对晚稻产量无显著影响;C20处理显著提高早、晚稻钾素吸收,对早稻氮素和磷素吸收有增加的趋势,但未达显著水平。试验进行4年后,C20处理显著提高土壤有机质含量和pH值。因此,在本试验中的酸性红壤上一次性施用生物炭后的第4年,生物炭仍然对双季水稻产量和土壤肥力具有提升效应。

Residual Effects of Biochar on Yield,Nutrient Uptake and Soil Properties in Double Ricecropping System

Biochar plays a critical role in improving soil quality and crop yield.However,most of the current research focused mainly on the short-term effects of biochar;little evidence existed regarding its long-term effects on crop yield and soil fertility.In order to clarify the residual effects on the yield,nutrient uptake and soil properties of double-season rice after 3 years of application of biochar,no biochar(C0)and one-time application of biochar 20 t/hm^2(C20)were set up in 2015,conventional rice Zhongjiazao 17(early rice)and hybrid rice Wuyou 308(late rice)were used as tested varieties.The results showed that biochar significantly increased the grain yield of early rice,but had no significant effect on grain yield of late rice.Biochar significantly improved K uptake in both the early and late rice seasons,and tended to increase N and P uptake.In addition,biochar significantly increased the soil pH value and the content of soil organic matter.Therefore,applying biochar can simultaneously enhance rice yield and improve soil fertility even after 4 year in the double rice cropping system in the acidic red soil.