土壤对Pb污染的缓冲特性研究

为了探讨Pb在土壤中的有效性及其对土壤污染的影响,用Pb、Cu、Cd和Zn模拟污染石灰性紫色土、酸性紫色土和黄壤(单一污染和复合污染)后,分析模拟污染土壤中Pb的有效量变化.利用缓冲性指标分析土壤抗铅污染的能力.结果表明,3种土壤对Pb的缓冲能力不同,由大到小顺序为:缓冲能力石灰性紫色土、黄壤和酸性紫色土.3种土壤对铅的缓冲能力随加入的单一污染物或复合污染物Pb、Cd、Cu、Zn的浓度增高而降低.

On the soil's capacity to buffer the lead pollution

The paper aims to present the authors' study on the capability of different soils to alleviate pollution brought about by lead. As is known, heavy metals left over by the industrial sewage to the soil and, particularly, to crop fields, is generally thought of as a kind of harmful pollution. For this purpose, the elements of cadmium, copper, zinc and lead have been taken by the authors to simulate different kinds of contaminated soil, including calcium-polluted purple soil, acidic purple soil and yellow soil, etc. most of which are contaminated by one single element or compounds containing such elements. In doing so, special attention has been paid to the simulated study of the availability variables of lead in the soils, whose capacities of anti-pollution are analyzed by means of their buffer indexes. The results of our analyses indicate that there are three main kinds of soil with different buffer capacities on lead: the calcium purple soil, the acidic purple soil and the yellow soil. Comparing them in accordance with the buffer indexes, it can be found that the calcium purple soil enjoys the strongest buffer capacity whereas the acidic purple soil has the weakest, with the yellow soil standing between. However, all of them enjoy the same tendency to buffer the pollution caused by lead. In addition, the tendency would be reduced with the increase of concentration of the single or compound pollutants, including lead itself.