广东省东南部菜地水田砷含量空间分布

发布时间：2018-12-14 21:17

【摘要】：针对稀疏采样条件下农用地土壤砷含量空间分布难以高效准确识别的问题,以广东省东南部农用地为例,采集表层土壤(0~20 cm)样本104个,借助空间分析与多元回归建模手段,分菜地、水田和果园3类农用地分析土壤砷含量统计特征、模拟揭示土壤砷含量空间分异的成因与空间分布格局。结果表明:1)研究区农用地土壤砷含量总体上达标,但个别样点土壤砷含量值高达137.80 mg/kg,显著高于国家土壤环境质量二级标准(GB156182-1995);2)3类农用地中菜地土壤砷含量最高、水田次之、果园相对较低,均值分别为11.04、9.89和2.54 mg/kg;3)各类农用地土壤砷污染来源不同,菜地砷污染主要在不同地形条件下,受河流污水灌溉和烟囱排放的废气沉降随地表径流累积影响,在空间上呈现北部偏高、其他地区偏低的分布格局;4)水田砷污染受河流污水灌溉影响显著,空间上呈现南北部偏高、中部地区偏低的污染格局。研究结果对在稀疏采样监测地区开展农用地土壤重金属污染制图与精细防控策略的制定提供了一种行之有效的方法。
[Abstract]:In order to solve the problem that the spatial distribution of arsenic content in agricultural land is difficult to identify efficiently and accurately under sparse sampling conditions, 104 samples of surface soil (0 ~ 20 cm) were collected by spatial analysis and multivariate regression modeling, taking agricultural land in the southeast of Guangdong Province as an example. The statistical characteristics of arsenic content in soil were analyzed by three types of agricultural land, namely vegetable field, paddy field and orchard, and the spatial distribution pattern and cause of spatial differentiation of arsenic content in soil were revealed by simulation. The results showed that: 1) the arsenic content of agricultural land in the study area was up to the standard on the whole, but the value of arsenic content in the soil reached 137.80 mg/kg, significantly higher than that of the second grade national standard for soil environmental quality (GB156182-1995); 2) the content of arsenic in vegetable soil was the highest in the three types of agricultural land, followed by paddy field, and the orchard was relatively low, with the mean values of 11.04 mg/kg; and 2.54 mg/kg;, respectively. 3) the sources of arsenic pollution in different agricultural land are different. The arsenic pollution of vegetable land is mainly affected by the accumulation of surface runoff by river sewage irrigation and exhaust gas deposition of chimney discharge under different topographic conditions, and the north side of the soil is relatively high in space. Low distribution pattern in other areas; 4) arsenic pollution in paddy fields was significantly affected by river sewage irrigation, and the spatial distribution of arsenic pollution was higher in the north and south and lower in the central region. The results provide an effective method for mapping and fine control strategies of heavy metal pollution in agricultural soil in sparse sampling monitoring area.
【作者单位】：中南大学有色金属成矿预测与地质环境监测教育部重点实验室;中南大学冶金与环境学院国家重金属污染防治工程技术研究中心;
【基金】：中南大学‘创新驱动计划’项目(2015CXS005) 中国博士后科学基金特别资助项目(2013T60780)
【分类号】：X53

【相似文献】