竹炭有机肥对水旱作物生长发育及镉积累的影响

Effects of Bamboo Charcoal Organic Fertilizer on Growth and Cadmium Accumulation in Paddy and Upland Crops

为筛选适合镉污染农田水旱作物的有机肥,选择湖南典型镉污染农田土壤,通过室内培养试验研究竹炭有机肥对水稻、小白菜两类作物生长发育和镉积累的影响。结果表明:适量增施竹炭有机肥显著增加水稻、小白菜生物量,施用量为0.66 g/kg时,水稻生物量相比CK增加97%,同时水稻根系、茎叶中镉含量分别下降38.8%和18.8%,小白菜株高相比CK有所增加,小白菜镉含量下降34%。竹炭有机肥施用量平均每增加0.5 g/kg,土壤pH增加0.1个单位,同时土壤有效镉含量随有机肥施用量增加呈降低趋势,1.33 g/kg处理下土壤有效镉含量降幅为9.2%。竹炭有机肥和氧化钙复配处理有效降低水稻镉积累量,在旱地农田的施用方式有待改良。研究表明适量增施竹炭有机肥能提高作物产量,降低镉在土壤-水旱作物系统中的迁移效率,能有效降低作物镉的积累量。

In order to screen suitable organic fertilizer for paddy and upland crops in cadmium-polluted farmland,the typical cadmium-polluted farmland soil in Hunan Province was selected,and the effects of bamboo charcoal organic fertilizer on the growth and cadmium accumulation in rice and Chinese cabbage were studied by laboratory culture experiments.The results show that an appropriate application of bamboo charcoal organic fertilizer significantly increases the biomass of rice and Chinese cabbage.Specifically,the application of 0.66 g/kg of bamboo charcoal organic fertilizer leads to a 97%increase in rice biomass compared with the control(CK).Moreover,cadmium content in the roots,stems,and leaves of rice drops by 38.8%and 18.8%,respectively.The height of Chinese cabbage increases compared with the CK,and cadmium content in Chinese cabbage decreases by 34%.As the application rate of bamboo charcoal organic fertilizer increases by 0.5 g/kg,soil pH increases by 0.1 unit.Furthermore,effective cadmium content in soil decreases with the increasing application of organic fertilizer,with a 9.2%reduction observed under the treatment of 1.33 g/kg bamboo charcoal organic fertilizer.The combination treatment of bamboo charcoal organic fertilizer and calcium oxide can effectively reduce cadmium accumulation in rice.However,the application method in dry farmland requires further improvement.The research shows that the application of bamboo charcoal organic fertilizer can increase crop yield and reduce the migration efficiency of cadmium in soil-paddy and upland crop systems,thus reducing the cadmium accumulation in crops.