本文關(guān)鍵詞：珠三角稻田銅、鎘和砷有效性的地球化學(xué)機(jī)制　出處：《廣西大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 重金屬 理化性質(zhì) 形態(tài) 富集系數(shù) 空間變異 水稻

【摘要】：本論文研究區(qū)域以廣東省珠三角為主,對(duì)研究區(qū)內(nèi)采集的191個(gè)樣品利用GIS、空間分析方法對(duì)土壤重金屬(Cd、Cu、As)含量、形態(tài)和稻米重金屬含量以及土壤理化性質(zhì)進(jìn)行分析；研究了珠三角地區(qū)土壤-水稻系統(tǒng)重金屬含量在空間上的分異情況。探討了土壤理化性質(zhì)對(duì)水稻重金屬跟土壤重金屬形態(tài),以及土壤重金屬形態(tài)對(duì)水稻重金屬關(guān)系。本文主要的結(jié)論如下：1、珠三角土壤中銅、鎘、砷都受不同程度污染,Cd的污染程度超過(guò)背景值0.09mg.kg-1的2.5倍。珠三角地區(qū)水稻Cd、As的超標(biāo)率分別為22.51%、21.47%；土壤-水稻系統(tǒng)中銅、鎘變異都具有強(qiáng)烈的空間相關(guān)性,但As變異還受一部分人為活動(dòng)因素影響。2、珠三角地區(qū)的土壤重金屬Cu、Cd、As含量空間分布特征沿著珠江流域高于其他區(qū)域；稻米重金屬總量空間分布特征顯示,Cu、Cd沿著珠江流域濃度高于其他區(qū)域。稻米As與土壤中As含量空間分布相對(duì)立。3、土壤理化性質(zhì)與土壤中的重金屬形態(tài)相關(guān),土壤有機(jī)質(zhì)含量、酸堿度、粘粒含量的增加,土壤中相對(duì)穩(wěn)定形態(tài)的重金屬含量增加。4、水稻對(duì)重金屬的富集作用不同,且CdCuAs;土壤中不同形態(tài)重金屬的生物有效性為HC1CaC12≈NaHAOcDCB。5、土壤中游離態(tài)和無(wú)定型態(tài)鐵對(duì)水稻不同器官的Cu、Cd吸收具有促進(jìn)作用,對(duì)稻米、稻殼、稻桿對(duì)As吸收具有抑制作用。
[Abstract]:In this paper, the Pearl River Delta of Guangdong Province is the main area of study, 191 samples collected in the study area using the GIS-spatial analysis method for the content of heavy metals in the soil. Morphology, heavy metal content of rice and physical and chemical properties of soil were analyzed. The spatial differentiation of heavy metals in the soil-rice system in the Pearl River Delta region was studied. The effects of soil physical and chemical properties on heavy metals and soil heavy metal forms in rice were studied. The main conclusions of this paper are as follows: 1, Cu, CD, as in Pearl River Delta soil are polluted by different degrees. The pollution degree of CD was 2.5 times higher than that of background value of 0.09 mg 路kg ~ (-1). In the Pearl River Delta region, the exceeding rate of CD ~ (2 +) as was 22.51g 路kg ~ (-1) and 21.47%, respectively. The variation of Cu and CD in soil-rice system has strong spatial correlation, but as variation is also affected by some artificial activity factors. The spatial distribution of as content is higher than that of other regions along the Pearl River Basin. The spatial distribution characteristics of total heavy metals in rice indicated that the concentration of as in rice was higher than that in other regions along the Pearl River valley, and the spatial distribution of as in rice was opposite to that in soil. The physical and chemical properties of soil were related to the heavy metal forms in soil. The contents of organic matter, pH, clay and the relative stable form of heavy metals in soil increased by 4. 4. The enrichment of heavy metals in rice was different, and CdCuAs. The bioavailability of different forms of heavy metals in soil was HC1CaC12 鈮，

本文編號(hào)：1403307