强还原处理对西瓜连作土壤性质及西瓜产量的影响

Effects of reductive soil disinfestation (RSD) on continuous cropping soil properties and watermelon yield

在连续种植8年的设施西瓜大棚中,以不施有机肥为对照,比较农民习惯处理(FTF,添加鸡粪7.5 t·hm-2)和强还原处理(RSD,添加玉米秸秆15 t·hm-2)对设施土壤理化性质、可溶性盐含量以及细菌和真菌多样性指数的影响,测算西瓜产量和经济效益,分析改良后土壤理化性质与西瓜产量的关系。结果表明:RSD处理可显著提高土壤pH,显著降低土壤电导率,有效消减土壤所积累的致酸离子NO-3和SO42-,且显著降低Na+、K+、Ca2+、Cl-、HCO-3等盐基离子含量。土壤细菌和真菌的多样性指数(香农指数和超指数)显著增加。RSD处理后,设施西瓜产量较FTF增产18%,增加的经济收益可达31 860元·hm-2。相关分析表明,土壤有机质、速效磷和速效钾含量与西瓜产量显著正相关。

In this study, we designed two treatments, including farmers’ traditional fertilization(FTF, adding chicken manure 7.5 t·hm-2) and reductive soil disinfestation(RSD, adding corn straw 2.25 t·hm-2), to quickly and effectively improve the soil quality and curb the degradation of the cultivated soil. The effects of FTF and RSD on the physical and chemical properties, soluble salt content, bacterial and fungal diversity index of the facility soils were measured. The watermelon yields and economic benefits of different treatments were recorded. The results showed that RSD treatment could significantly increase soil pH, and significantly reduce soil electric conductivity. Moreover, the acid-forming ions NO-3 and SO42- concentrations were effectively reduced by RSD treatment. Additionally, the accumulated Na+, K+, Ca2+, Cl- and HCO-3 in facility cultivation soils could be significantly reduced by the RSD treatment, and the soil electric conductivity was also decreased rapidly. RSD treatment could significantly increase the soil bacteria and fungi diversity index(the Shannon index and the Chao index). After RSD treatment, the yield of watermelon was 18.6% higher than that of the FTF treatment. The economic benefit could reach 31 860.6 yuan·hm-2. Correlation analysis showed that the soil organic matter, available phosphorus and available potassium content were significantly positively correlated with watermelon yield.