Qi ZhiPing

Bio: Qi ZhiPing is an academic researcher from Chinese Academy of Tropical Agricultural Sciences. The author has contributed to research in topics: Arable land & Soil conservation. The author has an hindex of 2, co-authored 5 publications receiving 93 citations.

Assessment of Soil Heavy Metal Pollution with Principal Component Analysis and Geoaccumulation Index

Abstract: The assessment of pollution levels of heavy metals soil contamination is significant to human health and environmental management. The purpose of this article is to apply two methods, which are Principal component analysis (PCA) and Geoaccumulation index ( I geo ), to assess heavy metals contamination levels in the area around copper mine tailing, and to compare the results with Hakanson potential ecological risk index techniques (RI). The rank of soil Cd pollution levels, which is assessed using I geo , is consistent with the one by RI, while the PCA assessments result of comprehensive contamination level in soil discrepancy with RI and I geo . PCA concerned with the distribution of all elements in soil, while I geo and RI are mainly determined by the elements with high concentration or big Toxic Response Factor value. The combined application of PCA and I geo can effectively identify the comprehensive and single pollution levels of elements in soil, thus important to the extent determination of heavy metals pollution in soil.

Relationship between paddy soils cadmium pollution and cadmium content in rice.

Abstract: Cadmium(Cd)is important contaminants in agricultural soil and threatening agriculture and human health.With the development of industry and agriculture,the soil heavy metal cadmium pollution becomes more and more serious.In this study,two high-yielding rice cul-tivars currently used in the local production,Boyou 225,Short glutinous treated with five levels of cadmium in a pot experiment was conduct-ed to study the correlation between Cd accumulation of brown rice and that of paddy soils.Results showed that cadmium was not distributed uniformly in each part of rice plants.Most of the absorbed Cd assembled in the root,the upper,the less.The law of distribution of Cd in differ-ent organs of rice was:root stem rice husk kernels.In rice roots and stems and leaves,cadmium was mainly distributed in the cell wall.Soluble components of cells,cell distribution of low cadmium.That is,F1(Cell wall) F3(soluble part) F2(cell organelles and membrane part).The rice varieties exhibited the genetic character on the Cadmium accumulation.The Cadmium contents of the grains increased with the increasing Cd concentration in soil.According to the state limit of cadmium in rice,the standard(GB 2762-2005),Content≤ 0.2 mg.kg-1.In this study,tropical paddy soil total Cd threshold were Boyou225(Cd total)= 2.0 mg.kg-1;Short glutinous(Cd total)= 3.1 mg.kg-1.There-fore,for reducing the risk of the humanity to heavy metal,the rice varieties with the low capability of accumulating heavy metal in grains could be planted in a polluted soil.

Distribution characteristics of zinc in arable land soil of northwestern Hainan.

Abstract: 【Objective】 Zinc distribution in the arable land soil of northwestern Hainan(Danzhou,Baisha,Changjiang,Dongfang) was assayed in order to identify the area with the highest content of zinc and provide references for agricultural planning in Hainan.【Method】 On basis of field sampling and indoor analysis(geo-statistics and spatial analysis),the distribution of zinc in term of spatial and soil profile layers(inc.plow horizon,subsurface layer,waterloggogenic horizon and parent material horizon) was illustrated.【Result】 The results indicated that the content of soil zinc was generally low with the highest content of 85.94 mg/kg only.The spatial distribution varied significantly in all soil horizons.Soils with zinc exceeding 50 mg/kg were mainly distributed in pyroclastic area,northwest Changjiang,and west Dongfang.The content of zinc in parent material horizon was the highest,being 30.30 mg/kg,followed by the waterloggogenic horizon.The content of zinc in soils of plow layer was similar to that of subsurface layer.【Conclusion】 The content of soil zinc was generally low in northwestern Hainan.The distribution of soil zinc was subject to parent material distribution,the soil pH and chemical fertilizers applied to arable land.

Temporal and spatial distribution of soil nutrients in tropical arable land of China - a case study of Dongfang City, Hainan.

Abstract: 【Objective】Spatial and temporal distribution characteristics of soil nutrients in tropical arable land of China and the influencing factors were analyzed in order to provide references for managing soil nutrients in tropical arable land. 【Method】Based on the field survey,soil sampling and nutrient analyzing, soil nutrient status was studied and compared with the results of the Second National Soil Survey. Spatial and temporal distribution characteristics of soil nutrients in tropical arable land were explored. 【Result】The results indicated that the contents of nutrients in cultivated soil varied significantly in Dongfang City. The arable land soil was acidic soil as a whole with pH of 5.49. The concentration of soil organic matters, macronutrients(N,P and K) and medium nutrients(Ca,Mg and S) in arable land soil was relatively lower in Dongfang City. However,the contents of available B and available Zn were sufficient. Compared with the results of the Second National Soil Survey,soil acidification was more evident. The concentration of organic matters decreased significantly,which was 6.0 g/ kg,and the available P content increased by 15.2 mg/kg. 【Conclusion】In Dongfang City, soil nutrients content was not sufficient and distributed unevenly. Soil acidification and variation of soil nutrients were related to climate factors,distribution of soil parent materials and chemical fertilizer application.

Distribution of copper in soil and rice system of Hainan Island, China

Abstract: This research aimed to discover the distribution and the primary influence factors of Cu in the soil-rice systems of tropical farmland. Soil samples of farmland and rice plant (stalk and polished rice) from the western region of Hainan Island were collected and studied. The results showed that the average Cu content in the topsoil of the study area was 15.75 mg kg-1; the highest Cu content (45.92 mg kg-1) was found in the rice fields of the northern area, where pyroclastic parent material is distributed. Thus, there is a potential for Cu contamination of the rice grown in this region. The average contents of Cu in the rice stalks and polished rice were 16.9 and 5.68 mg kg-1, respectively, indicating that the stalks had a larger capacity for Cu bioaccumulation than the polished rice. The bioaccumulation factor (BAF) of Cu in rice was found to decrease with increased Cu contents in the soil. In regards to the northern farmlands with high Cu contents in the soil derived from pyroclastic deposits, an alkaline fertilizer should be used to prevent the risk of Cu pollution in the polished rice, as soil acidification can promote the uptake and accumulation of Cu to some extent.

Pollution indices as useful tools for the comprehensive evaluation of the degree of soil contamination–A review

Abstract: The paper provides a complex, critical assessment of heavy metal soil pollution using different indices. Pollution indices are widely considered a useful tool for the comprehensive evaluation of the degree of contamination. Moreover, they can have a great importance in the assessment of soil quality and the prediction of future ecosystem sustainability, especially in the case of farmlands. Eighteen indices previously described by several authors (Igeo, PI, EF, Cf, PIsum, PINemerow, PLI, PIave, PIVector, PIN, MEC, CSI, MERMQ, Cdeg, RI, mCd and ExF) as well as the newly published Biogeochemical Index (BGI) were compared. The content, as determined by other authors, of the most widely investigated heavy metals (Cd, Pb and Zn) in farmland, forest and urban soils was used as a database for the calculation of all of the presented indices, and this shows, based on statistical methods, the similarities and differences between them. The indices were initially divided into two groups: individual and complex. In order to achieve a more precise classification, our study attempted to further split indices based on their purpose and method of calculation. The strengths and weaknesses of each index were assessed; in addition, a comprehensive method for pollution index choice is presented, in order to best interpret pollution in different soils (farmland, forest and urban). This critical review also contains an evaluation of various geochemical backgrounds (GBs) used in heavy metal soil pollution assessments. The authors propose a comprehensive method in order to assess soil quality, based on the application of local and reference GB.

Cadmium (Cd) distribution and contamination in Chinese paddy soils on national scale.

Abstract: Rice is a staple food by an increasing number of people in China. As more issues have arisen in China due to rice contaminated by cadmium (Cd), Cd contamination in arable soils has become a severe problem. In China, many studies have examined Cd contamination in arable soils on a national scale, but little studies have focused on the distribution of Cd in paddy fields. This study explored the spatial pattern of Cd in paddy soils in China, made a preliminary evaluation of the potential risk, and identified the most critically contaminated regions based on the domestic rough rice trade flow. The results showed that Cd concentrations in paddy soils in China ranged from 0.01 to 5.50 mg/kg, with a median value of 0.23 mg/kg. On average, the highest Cd concentrations were in Hunan (0.73 mg/kg), Guangxi (0.70 mg/kg), and Sichuan (0.46 mg/kg) provinces. Cd concentrations in paddy soils in central and western regions were higher than those in eastern regions, especially the southeastern coastal regions. Of the administrative regions, Cd standard exceedance rate was 33.2 %, and the heavy pollution rate was 8.6 %. Regarding to Cd of paddy soil, soil environmental quality was better in Northeast China Plain than in Yangtze River Basin and southeastern coastal region. Mining activities were the main anthropogenic pollution source of Cd in Chinese paddy soil. Based on rice trade, more of the Chinese population would be exposed to Cd through intake of rice produced in Hunan province. Certain regions that output rice, especially Hunan province, should be given priority in the management and control of Cd contamination in paddy soil.