巢湖地区稻虾共作模式对稻田土壤肥力的影响

Effects of the integrated rice-crayfish mode on soil fertility in Chaohu Lake region

为监测巢湖地区稻虾共作模式生产前后稻田土壤肥力的变化,2016年度在巢湖周边设置2个监测区域,分别在水稻种植前、营养生长期和收割后3次采集稻田土壤样本,测定土壤有机质、全氮、全磷、全钾、碱解氮、有效磷、速效钾和阳离子交换量等肥力指标;并结合水稻和小龙虾产量及施肥投喂管理,比较了常规单作稻田和稻虾共作模式稻田土壤肥力变化及生产效益。结果显示,稻虾共作模式水稻产量均高于常规单作稻田,可增产2%~3%;正常投喂时,共作模式可收获小龙虾1 200 kg·hm^(-2)以上。水稻生产后,A区稻虾共作模式田的肥力水平普遍高于单作稻田,B区域稻虾共作模式田土壤有机质、全磷、阳离子交换量水平高于单作稻田(P<0.05),其余肥力因子差异不显著(P>0.05)。总体而言,稻虾共作模式更有助于保持监测区域稻田土壤肥力。

Two sampling areas around Chaohu Lake were set up to monitor the variation of soil fertility in 2016. We collected soil samples before rice plantation, vegetative growth stage and after harvest, respectively. Total nitrogen, total phosphorus, total potassium, available nitrogen, available phosphorus, available potassium, and cation exchange capacity were analyzed. The rice yield was evaluated. The results showed that the rice yield was 2%-3% higher in the integrated rice-crayfish mode than in the monoculture rice mode. The yield of crayfish was above 1 200 kg·hm^（-2） under the regular feeding. The soil fertility was better in the integrated rice-crayfish mode in sampling area A（P0.05） than the monoculture rice mode. The organic matter, total phosphorus, and cation exchange capacity were higher than those in the integrated rice-crayfish mode in sampling area B with no significant difference in other fertility factors（P0.05）. In general, the integrated rice-crayfish mode was more conducive to maintaining soil fertility.