【作者】 孙蕾；

【导师】 刘惠清；

【作者基本信息】 东北师范大学 ， 自然地理学， 2008， 硕士

【摘要】 农安县作为国家重点商品粮基地县,不但为当地居民生产农副产品,也是省会长春市主要农副产品的供应和加工基地,每年还为国家输送商品粮百万吨。近年来,随着人口的增加和经济的发展,农安县耕地土壤重金属污染日趋严重。研究其耕地土壤重金属污染状况将对农安县今后更有效保护与合理利用现有的耕地资源、加快农业结构调整、发展无公害农产品生产、实现农业生产标准化以及保证粮食和食品安全等都起到十分重要的作用。本文运用环境科学、地理学原理,以及SPSS、地理信息系统(GIS)技术,以农安县为研究区域,全面评价县域内耕地土壤重金属污染状况,深入探讨了重金属空间分异特征及影响机理,取得了以下几点认识:第一,农安县土壤环境质量总体良好。在采集的162个样本中,Pb、As、Cd、Cr的单项污染指数、单因子综合指数和多因子综合污染指数均达到NY/P391-2000标准。Hg单项污染指数有107个样点符合NY/P391-2000标准,157个符合GB/T18407-2001标准,5个不合格;Hg多因子综合污染指数有103个样点符合NY/P391-2000标准的安全、清洁水平,157个样点符合GB/T18407-2001标准的安全、清洁水平,5个样点处于警戒级、尚清洁水平;Hg单因子综合指数有7个乡镇达到NY/P391-2000标准,15个乡镇仅达到GB/T18407-2001标准。第二,农安县耕地土壤中五种重金属的空间变化趋势是:西北与东南部指数值大致都比较高。As的高值集中在中部、西北和东南部;Cd高值集中于北部、西北部及西南部的边缘区;Cr的分布趋势是从东北向西南高低相间分布;Pb的分布趋势是从西向东低高值相间分布;Hg分布与多因子综合污染评价等级图类似,都大致集中在西部、西北部与东南部。第三,农安县耕地土壤重金属污染地域分异与土壤属性、水文分布等自然因素及乡镇、交通、农业生产、土地利用类型等人为因素有关,其中以水文分布、农业生产中的畜禽养殖业等影响为主。所有影响因素的影响力为:水文条件>畜禽养殖业>城镇、交通>农膜用量>土壤属性>土地利用类型>化肥用量>农药用量。更多还原

【Abstract】 Nong’an County, as the key basic County of the State, not only produces agricultural products for local residents, but also supplies and processes the mainly agricultural production for its capital city, Changchun, and it also supplies millions of tons of marketable grains for our Country. In recent years, with the increasing of population and developing of economy, the heavy metal pollution problem in farmland soils in Nong’an County has been increasingly serious. Researching on heavy metal contamination in farmland soils will play a very important role in protecting more effectively and utilizing rationally the existing land resources, speeding up agricultural restructuring, developing pollution-free agricultural production to achieve standardization of agricultural production, and guaranteeing food and grocery security.Based on the environmental science principles, geography principles, and SPSS technology, geographic information system (GIS), taking farmland soils in Nong’an County as study area, the author evaluated roundly the heavy metal contamination in farmland soils, and disscussed deeply the spatial variation of heavy metals and impact mechanism. The following conclusions were drawn from the analysis.Ⅰ.The quality of the most soil environment was good in Nong’an County. In the 162 soil samples, the single pollution indexes, single-factor composite indexes and multi-factor integrated indexes of Pb, As, Cd, Cr all reached NY/P391-2000 standard. As for Hg, the single index is that 107 samples met NY/P391-2000 standard, 157 samples met GB/T18407-2001 standard and 5 samples failed; the multi-factor integrated index is that 103 samples met NY/P391-2000, in the safe and clean level, 157 samples met GB/T18407-2001, in the safe and clean level, and 5 samples failed, in the alert level but still clean; the single-factor composite index is that 7 townships met NY/P391-2000 standard, 15 townships only met GB/T18407-2001 standard.Ⅱ.The spatial variation trend of five heavy metals in farmland soils, Nong’an County, was that the index values of five heavy metals were mainly high in northwest and southeast. The high value of As concentrated in the central, northwest and southeast; Cd focued on the edge of north, northwest and southwest area; the distribution trend of Cr was interphase from the northeast to southwest; the distribution trend of Pb was interphase from west to east with low and high value; the distribution of Hg was similar to the multi-factor integrated pollution ratings map, which generally concentrated on the west, northwest and southeast.Ⅲ.The regional differentiation rules of heavy metal contamination in Nong’an County farmland soils related natural factors (the soil attribute, hydrological distribution) and human factors (rural townships, transportation, agricultural production, land use types), which were mainly affected by hydrological distribution and the livestock and poultry breeding in the agricultural production. The influence order of all influencing factors was: hydrological distribution>livestock and poultry industry>urban, transportation>plastic sheeting>soil attributes>land use types>fertilizer>pesticide.更多还原