Search

[Objective] Urbanization is currently one of the most significant features in China. In the progress of urbanization, some lands in the newly-built city that not developed currently are left for planting crops, while the change of land use poses new threat for farming, especially the soil heavy metal (SHM) pollution. In the present paper, taking Chenggong New District, Kunming as an example, we investigated the status of SHM pollution across 28 farmlands in Chenggong. [Method] The contents of soil Cu, Ni, Pb, and Zn were analyzed. Single factor pollution index (Cu, Ni, Pb, Zn), Nemerow integrated pollution index and Hankanson potential ecological risk index for each farmland were calculated. Spatial autocorrelation for each heavy metal was investigated based on Moran' s I. [Result] N emerow integrated pollution index ranged from 1. 39 - 3. 43, indicated the different extent of SHM pollution. The potential ecological risk index was small due to the low toxicological factors across the investigated heavy metals. The average Cu content was 2. 8 times for the background value and 1. 68 times for the national soil quality standard (II), besides, strong spatial autocorrelation and variation across the samples indicated the possible human influence. [Conclusion]These types of farmlands should be regulated and some heavy polluted lands should be prohibited for agricultural production to ensure the quality and safety of agricultural products. [ABSTRACT FROM AUTHOR]