【作者】 李明；

【导师】 杨新萍；

【作者基本信息】 南京农业大学 ， 工程硕士（专业学位）， 2018， 硕士

【摘要】 针对南方酸性镉(Cd)污染蔬菜产地食品安全问题,以湖南省湘潭县为例,对Cd污染程度不同(轻度Cd、中度Cd和重度Cd污染)的菜地土壤,采用不同的种植技术,如低Cd蔬菜种类的挑选、农业投入品检测、农艺调控措施、替代种植等,来保证当地生产的蔬菜食品安全,最终提出酸性Cd污染蔬菜产地种植结构调整技术建议,为我国南方酸性Cd污染蔬菜产地种植结构调整提供技术参考。主要研究结果如下:(1)对于酸性轻度Cd污染蔬菜地,建议选种菜苔、白菜、生菜、空心菜、雪里红、韭菜、葱、红薯、莴苣、白萝卜、姜、苦瓜、丝瓜、香瓜、辣椒和豇豆、扁豆、四季豆等低Cd积累蔬菜。(2)对于酸性中度(0.72±0.16 mg.kg-1)和重度(1.06±0.08 mg.kg-1)Cd污染蔬菜地,施用4 500 kg.ha1 CaC03或3 000 kg.ha-1 CaO降低蔬菜可食部位Cd含量的农艺修复措施具有用量少、成本低、效果显著及二次污染小等优势,但施用CaCO3或CaO,提升土壤pH的作用只能维持一年;施用4500、6000以及7500kg.ha-1的商品有机肥没有降低重度酸性Cd污染蔬菜地土壤生产的蔬菜Cd含量。(3)对于酸性中度Cd污染蔬菜地可安全种植菜苔、白菜、葱、白萝卜、苦瓜、丝瓜、香瓜及豇豆、扁豆、四季豆等低Cd积累蔬菜;如需种植香菜、芹菜等其它种类蔬菜,需要施用4 500 kg·ha-1 CaC03或3 000 kg·ha-1 CaO降低蔬菜可食部位Cd含量;对于酸性重度Cd污染蔬菜地可安全种植葱、苦瓜、丝瓜、白萝卜和肛豆、扁豆、四季豆等蔬菜,可以同时施用4 500 kg·ha-1 CaC03或3 000 kg·ha-1 CaO,进一步降低这些蔬菜可食部位Cd含量。(4)在酸性、平均Cd含量为12.5 mg.kg-1的蔬菜地开展替代种植试验,种植瓜萎和称猴桃,瓜萎种子、瓜萎皮及猕猴桃Cd含量分别为0.1 mg·kg-1、0.12mg.kg-1和0.11 mg-kg-1,均超过国家食品安全限值,不宜推广;替代种植非食用麻类作物,长势良好,具有推广可行性。在湖南省湘潭县,针对酸性Cd污染程度不同的蔬菜地,进行修复、替代种植试验,形成了基于土壤-蔬菜污染等级的“清洁农业投入品+施用CaC03或CaO+种植低Cd蔬菜+替代种植”的酸性Cd污染蔬菜地种植结构调整技术。这些措施可以降低湘潭当地居民食用Cd污染蔬菜导致的Cd摄入。更多还原

【Abstract】 Field experiments were conducted in a vegetable land with an elevated cadmium(Cd)concentration in the soil of Xiangtan county,Hunan province.The food safety problems of vegetable planted in area contaminated by Cd in the south of China were investigated.Different planting techniques were used,such as the selection of low Cd-accumulating varieties,agricultural inputs detection,regulation of agronomic measures and substitute planting to ensure the food safety of locally produced vegetable.As a result,an appropriate technology for safe production of vegetable in acidic Cd-polluted farmland was proposed,which provided a technical reference for the adjustment of planting structure on acidic Cd-polluted vegetable-growing land in southern China.The main findings were as follows:(1)It was recommended to plant vegetables with low Cd accumulation,such as flowering stalk,Chinese cabbage,romaine lettuce,water spinach,potherb mustard,leek,onion,sweet potato,lettuce,white radish,ginger,balsam pear,towel gourd,muskmelon,pepper and cowpea,hyacinth bean,kidney bean in low Cd-polluted vegetable land.(2)The application of 4 500 kg·ha-1 CaC03 or 3 000 kg·ha-1 CaO in moderate(0.72±0.16 mg·kg-1)and severe(1.06±0.08 mg·kg-·)Cd-polluted vegetable land had the advantages of low dosage,low cost,significant effect and little secondary pollution.However,the effects of application of CaC03 or CaO in Cd-polluted vegetable land can only be maintained for one year.Compared with the control,the application of 4 500,6 000,7 500 kg·ha-1 commercial organic fertilizer had no obvious effect in severe Cd-polluted vegetable land.(3)Low Cd-accumulated vegetables,such as flowering stalk,Chinese cabbage,onion,white radish,balsam pear,towel gourd,muskmelon,cowpea,hyacinth bean,kidney bean,can be safely planted in the acidic moderate Cd contaminated vegetable land.In contrast,4500 kg·ha-1 CaCO3 or 3 000 kg-ha-1 CaO was required to reduce the Cd concentration in other vegetables,such as coriander and celery.Moreover,low Cd-accumulated vegetables such as onion,balsam pear,towel gourd,white radish,cowpea,hyacinth bean,kidney bean,can be safely planted in acidic severe Cd-polluted vegetable land and 4 500 kg·ha-1 CaCO3 or 3 000 kg·ha-1 CaO can be applied to further reduce Cd concentration in the edible part of vegetable.(4)In the acidic vegetable land with an average Cd concentration of 12.5 mg·kg-1,substitute planting trials were carried out by planting trichosanthes kirilowii and kiwifruit,and the result showed the Cd concentration of the trichosanthes kirilowii seed,trichosanthes kirilowii and kiwifruit were 0.1 mg·kg-1,0.12 mg·kg-1 and 0.11 mg·kg-1,respectively,which exceeded the Chinese maximum permissible limits for Cd and should not be promoted.However,non-edible hemp crops showed a positive growth potential,as compared to the control.It had certain promotion feasibility.In Xiangtan county,Hunan province,remediation and substitute planting trails were carried out in acidic vegetable land with varying degree of Cd contamination.As a result,the appropriate technology for the adjustment of planting structure in the acidic Cd-polluted farmland based on soil-vegetable pollution levels;"clean agricultural inputs+CaCO3 or CaO+low Cd vegetables+ substitute plantings" was established.The feasible mitigation strategies could be applied to reduce the trophic transfer of Cd from contaminated vegetable to local population.更多还原