有机肥施用和外源镉添加对土壤理化性质、油菜生长及其镉积累的影响

Effects of Organic Fertilizer Combined with Exogenous Cadmium Addition on Soil Physical and Chemical Properties, Rape Growth and Cadmium Accumulation

  • 摘要: 采用盆栽试验方法,研究了施用鸡粪、牛粪、蚯蚓粪对外源添加不同浓度Cd土壤的酶活性等性状、盆栽作物油菜生长及其Cd吸收积累的影响;试验供试土壤Cd添加浓度为0、1、10、50 mg kg−1,以不施有机肥为对照、3种有机肥用量均为4%。结果表明:施用有机肥使土壤有机质含量、酶活性显著提高,施用鸡粪、牛粪处理土壤脲酶、磷酸酶活性最高,施用蚯蚓粪处理土壤的过氧化氢酶活性最高,但土壤pH值受施用有机肥的影响不明显。外源Cd的添加使土壤酶活性下降、且下降幅度与Cd添加浓度成正比;在高浓度添加Cd(10、50 mg kg−1)土壤,与对照相比三种有机肥处理有机结合态Cd比例提高37.6% ~ 117.3%,交换态Cd比例降低了14.7% ~ 28.3%。在Cd添加浓度为0、1、10 mg kg−1土壤,施用有机肥处理与对照相比,油菜叶片叶绿素含量、产量显著提高,且施用鸡粪和牛粪的效果又好于施用蚯蚓粪;而在Cd添加浓度50 mg kg−1土壤,只有施用蚯蚓粪处理油菜的叶绿素含量和产量提高,较未施用有机肥处理分别提高了38.8%和290%。在Cd添加量为10、50 mg kg−1土壤,施用有机肥处理油菜植株体内Cd浓度较未施有机肥处理下降了14.2% ~ 27.7%,而油菜体内Cd含量的降低效果以施用蚯蚓粪处理最好,优于施用鸡粪、牛粪处理。总之,从降低油菜体内Cd含量和提高油菜产量来看,在添加Cd浓度低于10 mg kg−1的土壤,施用鸡粪、牛粪的效果较好,而在添加Cd浓度达到50 mg kg−1的土壤则以施用蚯蚓粪的效果为更好。

     

    Abstract: Pot experiments were conducted to study the effects of chicken manure, cow manure and earthworm manure (application rate of 4%) on soil enzyme activities, rape growth and Cadmium (Cd) accumulation in soil added with different concentrations (0, 1, 10 and 50 mg kg−1) of exogenous Cd. The results showed that the organic matter content and enzyme activities of soil were significantly increased by the application of organic fertilizer. The activities of urease and phosphatase were the highest in the treatments of chicken manure and cow manure, and the activities of catalase were the highest in the treatment of earthworm manure. The effect of organic fertilizers on soil pH value was not significant. The soil enzyme activities were decreased with the concentration of Cd. Compared with the treatment of no organic fertilizer (CK), the proportion of organic-bound Cd in total Cd was increased by 37.6%-117.3% and that of exchangeable Cd was decreased by 14.7%-28.3% in the treatments of organic fertilizers with high concentration (10, 50 mg kg−1) of Cd addition. Compared with CK, the chlorophyll content and yield of rape were significantly increased by organic fertilizers application with 0, 1 and 10 mg kg−1 Cd addition, and the effect of chicken manure and cow manure was better than that of earthworm manure. In the soil added with Cd concentration of 50 mg kg−1, the chlorophyll content and yield of rape was increased by 38.8% and 290% respectively in the treatment of earthworm manure compared with CK. In the soil added with 10 and 50 mg kg−1 Cd, the Cd concentration of rape plants was decreased by 14.2%-27.7% in the treatments of organic fertilizers compared with CK, and the effect of earthworm manure was better than that of chicken manure and cow manure. In conclusion, chicken manure and cow manure applied to soil with Cd concentration less than 10 mg kg−1, and earthworm manure applied to soil with Cd concentration up to 50 mg kg−1 reduce the content of Cd in rape and increase the yield of rape.

     

/

返回文章
返回