【作者】 普锦成；

【导师】 章明奎；

【作者基本信息】 浙江大学 ， 土壤学， 2011， 硕士

【摘要】 在规模化养殖过程中,为了防止畜禽疾病、促进畜禽生长和满足畜禽对营养物质的需要,常常在饲料中加入了Cu等元素的添加剂,这导致了畜禽粪中Cu的富集。长期施用含高量Cu的畜禽粪便可引起农田土壤Cu的污染,甚至危及食品安全。为了了解由长期施用畜禽粪便引起的土壤Cu对农田生态系统的影响,寻求因长期施用畜禽粪便引起的土壤Cu污染的治理对策,本文开展了猪粪对铜在潮土--水稻系统中迁移转化影响和改良剂(粉煤灰、膨润土和磷灰石)对污染潮土中铜的钝化效果的模拟研究,探讨了在施用畜禽粪便的条件下不同污染水平的Cu对土壤Cu的有效性、Cu在水稻不同器官中的积累及对水稻生长的影响；研讨了施用三种不同改良剂对高pH值的潮土中Cu的钝化效果及对小麦、水稻中不同器官中Cu积累和作物生长的影响。目的是为畜禽粪便的合理施用和Cu污染土壤的改良提供依据。通过试验研究,获得的主要结果如下：(1)土壤中Cu的有效性随进入土壤的Cu与土壤作用时间的延长和猪粪施用量的增加而降低。在Cu污染的潮土中施用猪粪,可明显减轻Cu对水稻叶绿素的负影响。但猪粪的施用对水稻分蘖数量和千粒重无明显的影响。Cu在水稻籽粒、分蘖期茎叶、收获期茎叶和根系中的积累量均随猪粪施用量的增加而减少。水稻不同器官部位Cu含量有明显的差异,表现为：根>收获期茎≈分蘖期茎>籽粒。(2)在小麦-潮土系统中,随着Cu污染水平的提高,改良剂对Cu钝化效率逐渐降低。当Cu添加量为200 mg/kg时,三种改良剂均降低了土壤有效Cu,粉煤灰、磷灰石降低了水溶态Cu。但当Cu污染水平为400mg/kg时,对土壤有效Cu的降低作用不明显。三种改良剂施用在一定程度上可降低Cu对小麦根系的毒害,促进了根的伸长和发育,提高了小麦的根重和分蘖数。施用膨润土和磷灰石对籽粒中Cu含量的影响不大。(3)在水稻-潮土系统中,施用改良剂对土壤有效Cu的降低效果在试验前期比后期明显,在低铜添加量时比高铜添加量时明显。施用三种改良剂均可增加200mg/kg的Cu污染水平处理的水稻籽粒Cu含量,但可降低400 mg/kg污染水平的Cu处理的籽粒Cu含量。三种改良剂施用对水稻株高、叶绿素含量和千粒重影响均不明显。总体上,磷灰石在提高水稻的根系重量和穗重量方面的作用要优于粉煤灰和膨润土。(4)在本研究的Cu污染范围内(<800 mg/kg),无论是否施用猪粪和改良剂,潮土上生长的水稻和小麦籽粒中Cu的含量都低于我国食品卫生标准(GB14935-1994)的安全值(≤10 mg/kg)。更多还原

【Abstract】 Intensive confined livestock and poultry production systems generate large quantities of manure by-products, which have the potential for being recycled on land. Protecting the quality of the environment is a major consideration when developing management practices to effectively use manure by-products as a nutrient resource and soil conditioner in agricultural production system. To date, most of the environmental problems associated with land application of manure by-products have centered on the contamination of groundwater and/or surface water with two major nutrients, nitrogen (N) and phosphorus (P). With increasing use of trace elements such as Cu as nutritional supplement in the form of feed additive in intensive animal production industries, manure application has emerged as an important source of certain metals (e.g., Cu, Zn,and As) input in soils. At present, regulations governing livestock and poultry manure by-products are generally based on total N and/or P loading. Manure by-products are applied on land to primarily benefit from their N and/or P content, without regarding to their heavy metals contents. The danger lies in accumulation of manure-borne metals since they virtually don’t degrade with the potential of eventually becoming phytotoxic and thus resulting in problem of food security. In order to reduce the risk of offsite contamination, it is prudent to propose that land application guidelines for manure by-products be developed that consider their total composition rather than just only specific component (i.e., N and/or P). There are little informations on the effect of manure-induced Cu on farmland ecosystem, and the measures to control Cu pollution caused by applying animal manure. Therefore, the present research aims to examine the effects of pig manure application on transfer and transformation of Cu in a fluvio-aquic soil-crop system, and to understand the efficiency of three amendments (bentonite, apatite, and fly ash) to in-situ inactivation of Cu of the soil. The effects of pig manure-induced Cu contamination on accumulation of Cu and amount of available Cu in the soil, and Cu accumulations in different organs of both paddy and wheat were characterized. The effects of pig manure application and Cu pollution on the growth of paddy and wheat were investigated. The inactivation effeciency of the three amendments on Cu in a fluvio-aquic soil-crop system were also studied.The results obtained in the study are summarized as follows:(1)Availability of Cu in the soils decreased with increasing rate of pig manure application and increasing incubation time of added Cu with the soils. In fluvio-aquic soil contaminated with Cu, application of pig manure could reduce Cu contamination-induced negative effect on the chlorophyll content of paddy plant. However, application of pig manure had no significant effects on the tillers and grain weight. The concentrations of Cu in grain, stem and root of paddy plant decreased with increasing application rate of pig manure. The concentration of Cu in different organs of paddy plant decreased in the sequence of root>stem> grain.(2)Inactive effects of amendments on soil Cu decreased with increasing level of Cu contamination in the fluvio-aquic soil-wheat system. All of three amendments decreased the contents of soil available Cu, and fly ash and apatite decreased the water soluble Cu when 200 mg/kg of Cu was added to incubated soil. However, the effects of three amendments on decrease of soil available Cu were not significant when 400 mg/kg of Cu was added to incubated siul. Any of three amendments could reduce toxic hazard of Cu to wheat root in certain extern, promote the growth and root development of wheat and improve the root weight and tillers of wheat. The application of bentonite and apatite have no significant effect on Cu accumulation in grain.(3)In fluvio-aquic soil-paddy system, alleviation effects of the amendments on soil available Cu is more evident at earlier stage of the experiment than at later stage of the experiment. The effects were also more evident in soils contaminated with low level of Cu than those contaminated with high level of Cu. Application of any of three amendments increased Cu accumulation in grain of paddy growing in incubated soils with Cu treatment of 200mg/kg. However, it decreased Cu accumulation in grain of paddy growing in the soils with Cu treatment of 400mg/kg. Application of amendments has no significant effects on height, chlorophyll content and grain weight of paddy plant. In generally, the effects of three amendments on modification of soil physic-chemical property, reducing of Cu toxicity to wheat and paddy, and improvement of crop’s yield decreased in sequence of bentonite> apatite >fly ash. The effect of apatite on increase of root weight and grain weight of paddy was better than those of fly ash and bentonite.(4)At lower than 800 mg/kg of Cu was added in incubated soils under the study, whether applying pig manure and amendments or not, contents of Cu in the grains of paddy and wheat growing in all incubated soil were lower than 10 mg/kg, a food safety standards of China (GB14935-1994).更多还原