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[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]

【Objective】The present paper aimed to grasp the quality status of farmyard manure in Kunming tobacco-growing area and provide important reference for rational utilization and standardized production. 【Method】Farmyard manure samples were collected according to the principle of multi-points and random in Kunming tobacco-growing area,and carry out relevant index detection and comparative analysis according to the standard system of organic fertilizer for tobacco-planting.【Result】The pH value of farmyard manure was 8.27,the contents of organic matter, total nutrient and humic acids were 57.0 %, 5.33 % and 19.0 % respectively, and the volume weight was 0.55 g/cm~3, and the contents of available nitrogen, available phosphorus and available potassium were 0.08 %,0.30 % and 1.91 %,respectively. The farmyard manure had low content of available nitrogen, phosphorus and high content of available potassium, and the comprehensive performance of sheep manure and cattle manure was better than other types. The contents of total Cu, Pb and Cd in ordinary farmyard manure were 61.1, 23.9 and 1.68 mg/kg respectively, and the contents of total Cr, As, Hg and Zn were 24.9, 11.5, 0.19 and 221.5 mg/kg respectively, and the content of chloride ions was 0.42 %. However, in the five kinds of organic fertilizers, only the content of total Zn, Cu obviously exceeded the standard in pig manure. 【Conclusion】The quality of ordinary farmyard manure could meet the requirements of high-quality tobacco production as long as the production process was standardized and safety risks were controlled according to the standard of organic fertilizers. [ABSTRACT FROM AUTHOR]