围填海对滨海区域土壤重金属污染的影响

发布时间：2018-02-21 09:28

本文关键词： 围填海重金属污染污染现状潜在危害优先格局　出处：《南京大学》2017年硕士论文　论文类型：学位论文

【摘要】：随着人类围填海活动强度和范围的不断增加,滨海区域在过去几十年里的所面临的重金属污染问题日益严峻。重金属污染拥有潜伏性、较差的移动性和较长的滞留时间,它能够致使土壤质量严重下降,破坏生态系统的良性循环,对社会的可持续发展构成较大威胁,甚至严重危害人类的生存,长期以来倍受环境学家的关注。而作为我国重要湿地资源的盐城滨海区域,其土壤的重金属污染问题更是得到了全球范围内的广泛关注。本研究在探讨盐城滨海区域由围填海所产生的不同土地利用类型(自然栖息地(NH),堤坝围封(ER),农田(FL),水产养殖塘(AP)和工业区(IH))中重金属Cd、Cu、Pb、Zn污染现状(全量和污染评价指数)的基础上,运用有效性系数和释放率两个指标分析这些元素的潜在危害。同时本文还采用ArcGIS软件对重金属污染进行空间插值,并与该区域的生态服务价值相结合,运用地统计分析方法筛选出既具有较高生态服务价值又具有较轻重金属污染的区域作为重金属污染控制的优先区域,进而确定重金属污染控制的优先格局,旨在为盐城滨海区域的开发利用和土壤重金属污染的综合治理提供数据支持。相关研究结果表明:(1)在重金属污染现状方面,ER,AP,FL和IH中重金属元素的全量大多比NH中的对应浓度要高,特别是ER和FL中的Cd,AP,FL和IH中的Cu,AP和FL中的Pb以及FL和IH中的Zn,其全量均显著高于NH中的对应浓度。同时,重金属污染评价指数的分析表明,虽然四种重金属元素在各土地利用类型中均呈现出未污染的状态,但是围填海活动仍对FL和ER中的Cd,AP,FL和IH中的Cu,AP和FL中的Pb以及FL和IH中的Zn的污染程度产生了显著影响。(2)对于重金属的潜在危害而言,大多数重金属元素在这五种土地利用类型中的潜在危害都比较低,但是AP,FL中的Cd和ER中的Cu的有效性系数以及AP中的Cd和Zn的释放率都显著高于NH中的对应指标,特别是Cd,其有效性系数在FL(33%)和AP(32%)中甚至超过了 30%,这可能与这两个土地利用类型中相对较低的土壤pH和MnO的含量有关。(3)对于重金属污染的空间分布而言,其呈现出明显的南部区域小于北部区域的趋势,这可能与当地的自然条件和人为活动的干扰有关。此外,在重金属污染控制的优先格局方面,这些优先区域主要集中在北部的丹顶鹤自然保护区和射阳盐场以及南部的大丰麋鹿自然保护区,四卯酉闸和梁垛河闸周边的自然湿地和养殖塘等区域。这些区域具有较高的生态服务价值并且受到的重金属污染较轻,应在滨海区域重金属污染的治理及其土地利用等方面得到较多关注。
[Abstract]:With the increasing intensity and scope of human reclamation activities, the problem of heavy metal pollution in coastal areas has become increasingly serious in the past decades. Heavy metal pollution has latent, poor mobility and long stay time. It can cause a serious decline in soil quality, destroy the virtuous circle of ecosystems, pose a great threat to the sustainable development of society, and even seriously endanger the survival of mankind. For a long time, it has attracted the attention of environmentalists. As an important wetland resource of our country, Yancheng coastal area, The problem of heavy metal pollution in the soil has been paid more and more attention in the whole world. In this study, the different land use types (NH ~ (2 +)) produced by reclamation in the coastal area of Yancheng City (natural habitat), embankment enclosure (ERA), farmland flurries (FL) were studied. On the basis of the pollution status (total quantity and pollution evaluation index) of heavy metal CD ~ (2 +) Cu ~ (2 +) Pb ~ (2 +) Zn in aquiculture ponds (APL) and industrial area (IHN), The potential harm of these elements was analyzed by using the efficiency coefficient and release rate. At the same time, the ArcGIS software was used to carry out spatial interpolation of heavy metal pollution and combined with the ecological service value of the region. The region with high ecological service value and light heavy metal pollution was selected as the priority area for heavy metal pollution control by using the method of geostatistical analysis, and then the priority pattern of heavy metal pollution control was determined. The purpose of this study is to provide data support for the exploitation and utilization of coastal areas of Yancheng City and the comprehensive control of heavy metal pollution in soil. The results show that the total amount of heavy metal elements in FL and IH of Erlang APPU FL and IH is much higher than that in NH in the present situation of heavy metal pollution. The corresponding concentration of. In particular, the total concentrations of CDAPP in ER and FL, Cuanap in IH and Pb in FL and Znin in FL and IH were significantly higher than those in NH. Although the four heavy metal elements show unpolluted state in each land use type, However, reclamation activities still have a significant impact on the potential damage of heavy metals to the pollution levels of FL and ER CDAPA FL and IH Cuanap and FL, and of FL and IH Zn. The potential damage of most heavy metals in these five land use types was relatively low, but the availability coefficients of CD and ER in APFL and the release rate of CD and Zn in AP were significantly higher than those in NH. In particular, the availability coefficients of CDDs in FL-33) and APG32) even exceeded 30%, which may be related to the relatively low soil pH and the content of MnO in the two land use types) for the spatial distribution of heavy metal pollution. It shows an obvious trend that the southern region is smaller than the northern region, which may be related to the local natural conditions and the disturbance of human activities. In addition, in terms of the priority pattern of heavy metal pollution control, These priority areas are mainly concentrated in the Red crowned Crane Nature Reserve in the north and Sheyang Salt Farm and the Dafeng Milu Deer Nature Reserve in the south. Areas such as natural wetlands and breeding ponds around the Simaoyou Gate and the Liangduhe Gate. These areas are of high ecological service value and are less polluted by heavy metals. More attention should be paid to the treatment and land use of heavy metal pollution in coastal areas.
【学位授予单位】：南京大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X53

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