Zhou Shenglu

Accumulation of Heavy Metals in Different Parts of Wheat Plant from the Yangtze River Delta, China

With the rapid economic development and increased human activities, the soil heavy metal pollution has become a serious environmental problem in the world. This study investigated the heavy metal accumulation in soil and bioaccumulation in wheat in the Yangtze River Delta, particularly in Suzhou-Kunshan, to provide theoretical guidance for economic development and pollution control. Wheat plants were collected and divided into four parts: root, stem, leaf, and grain. The concentrations of eight heavy metals (Hg, As, Cr, Cu, Ni, Pb, Zn and Cd, As is a metalloid) in each wheat plant part were evaluated, and the accumulation and relationship of these heavy metals (HMs) were analyzed. Results indicated that the roots had the greatest accumulating capability among the four plant parts, also the roots are the main channel of heavy metal accumulation in wheat plant. The most and least accumulated HMs were Cd and Cr, respectively. Correlation analysis revealed a relationship between heavy metal concentration in the grains and other plant parts of wheat. However, no consistent pattern was found. This result could be attributed in part to the atmosphere-derived HMs in wheat; thus, outer contaminants and reactions might exist in the plants.

The Influence of Socio-economic Development on Soil Heavy Metals Accumulation in a Typical Region of Yangtze River Delta

Apply approach of time-space transfer and take soil covered in different years as a carrier, this paper constructed the historical record of soil heavy metals (HMs) content during 1950 to 2006 in Yixing city, an area with rapid socio-economic development in Yangtze River Delta of China, and discussed the impact of socio-economic development on soil HMs content and pollution indexes with gray correlative analysis model. Results are summarized as follows: (1) Variation in Cu, Ni, Pb, and Zn content showed a shape of stretched “U”, which inflexion point is the late 1970s or the early 1980s; The content of As appeared declining, by contrast, there was a notable accumulation of Cd; Co and Cr content showed comparatively stable oscillation. (2) Each index of socio-economy has a high and stable gray correlation degree with soil HMs content. Total population, usage amount of chemical fertilizer and total cultivated area are the three most important impact factors of soil HMs content, conversely, total freight volume, GDP and value of industry output in rural area have the weakest impact on soil HMs content. (3) Soil HMs pollution indexes showed the same trends as temporal variation in Cu, Ni, Pb, and Zn content. Usage amount of chemical fertilizer, total population and total grain yield are the three most important socio-economic factors that contribute to soil HMs pollution, enterprise amount, total cultivated area, gross value of farming, forestry, animal husbandry and fishery product as well as total freight amount have less impact on soil HMs pollution, last and least impact factors are GDP and value of industry output in rural area.

The Pollution Evaluation and Spatial Distribution of Soil Heavy Metals Surrounding Chemical Industrial Park

On the basis of collecting 39 surface soil samples in Nanjing Liuhe Chemical Industrial Park as well as its surrounding area, and determining the total contents of Cu, As, Pb, Hg, Cd, this article evaluated the pollution index of soil heavy metals with the application of single factor index method and Nemero pollution index method. Meanwhile, the authors used Ordinary Kriging Method to draw the spatial distribution map of heavy metals pollution and then analyzed the influence of chemical industry park on the soil with the difference in distance and wind direction. The result shows that the soil heavy metals pollution produces large harm, and the average composite pollution index which is 1.13 reaches the pollution level. The degree of heavy metal pollution is correlated with the distance from chemical industrial park, which is demonstrated that, the closer the site is to the industrial park, the higher the pollution index is. The influence radii of the different elements rank as Hg>Pb>Cd>Cu>As. Furthermore, the diffusion characteristic of the heavy metals in different directions is consistent with the wind direction, and the pollution index is higher in the downwind southwest and northwest direction.

Research about the Influences of River-Crossing Channel Construction on the Urban Expansion of Riverside City Zones

With Pukou District of Nanjing as an example, the paper introduces SLEUTH cellular automaton model and adopts the Land sat TM/ETM+ remote sensing image (30m*30m) data of five time phases (1988, 1995, 2000, 2004 and 2008) to carry out quantitative research on the influences of river-crossing channel construction on urban expansion from the angle of land use growth. The research shows that, 1) SLEUTH model could well simulate the characteristics of urban land growth in researched area, and could be primely applied to the research on urban expansion; 2) river-crossing channel construction will greatly vitalize the urban growth potential of researched area. The increased land for construction in Pukou District in 2020 and 2030 will reach up to 10,139 and 13,151 hektare, rising by 48.05% and 62.33% respectively over the base period years, 3) river-crossing channel construction could effectively drive the urban growth of researched area, but its contribution is decreasing year by year, especially riverside streets.

Research of Evaluation Information System of Urban Land Reserve Risk Based on GIS

Land reserve is an important mean for the intensive utilization and optimized allocation of land resources. But due to the influences of various uncertain factors in the operation of land reserve, there is some certain deviation between the actual return and expected return of land reserve, and this brings the possibility of sustaining losses. How to correctly evaluate and evade land reserve risks has become a hot-spot issue researched nowadays. At present, domestic related researches mainly make qualitative description of land reserve risks in the form of manual computation and drawing, there is not a quantitative research result, and the errors are relatively serious. The study integrates the spatial database of land reserve risks and the risk evaluation model base effectively in the form of information system, adopts multiple quantitative analysis methods such as mathematical modeling and fuzzy mathematics, etc. to carry out quantitative grading and prediction of various risks with the support of plentiful investigation and statistical data, and makes up the deficiency of previous researches. The result has some certain exploration and instruction meanings, and could assist with the decision making of national land department at some certain degree.

Spatial Variability Characteristic of Soil Heavy Metals Due to Industry Development of Typical Regions in Yangtze River Delta of China

This study attempts to evaluate the spatial variability characteristic of soil heavy metals in different industrial types. Therefore, concentrations of heavy metals in soils with different distances from solid, liquid and gas point source and nonpoint source were measured in Yixing, an area with intensive industrialization in Yangtze River Delta of China. The results show that 1) the enrichment of heavy metals in soils around point source is strong and concentrations of heavy metals in soils around solid point source are the highest, followed by liquid, and gas is relatively low. The types of enrichment element depend on the types of point source. Concentrations of heavy metals in soils with distance are significantly decreased. And affected by the prevailing wind, the area influenced by gas point source is the largest, followed by solid, and liquid is relatively small; 2) compared with point source, the enrichment of heavy metals in soils around nonpoint source is relatively weak, but its element types are complex. There are no significant changes of concentrations of heavy metals in soils with distance, but the influenced area is larger; and 3) affected not only by the prevailing wind direction, but also by industry layout, concentrations of soil heavy metals around nonpoint source are of difference in different directions. Due to the complexity of the enrichment element’s types of soil heavy metals and their combined effect in nonpoint source, the spatial variability is more complex. It means that taking effective measures to control nonpoint source is especially difficult.