Zhang Xue-lin

SPATIAL-TEMPORAL VARIATION OF HEAVY METAL ELEMENTS CONTENT IN COVERING SOIL OF RECLAMATION AREA IN FUSHUN COAL MINE

Grid method is employed for sampling covering soil at the test field, which is reclamation area filled by coal mining wastes for cropland in the Fushun coal mine, Liaoning Province, the Northeast China. The soil samples are taken at different locations, including three kinds of covering soil, three different depths of soil layers and four different covering ages of covering soil. The spatial-temporal variation of heavy metal element content in reclamation soil is studied. The results indicate that the content of heavy metal elements is decreasing year after year; the determinant reason why the content of heavy metal elements at 60cm depth layer is higher than that at 30cm depth layer and surface is fertilizer and manure application; the metal elements mainly come from external environment; there is no metal pollution coming from mother material (coal mining wastes) in plough layer of covering soil.

Regional ecological risk assessment of selenium in Jilin province, China

Integrating the biokinetic model of selenium with Monte Carlo analysis, this article carries out a quantitative study on ecological risk assessment in blood selenium levels of residents in Jilin province. The result shows that the established biokinetic model can be employed to predict the blood selenium levels of residents in a region. The predicted average blood selenium is 0.044 microg/ml and standard deviation is 0.013 microg/ml. Compared with the determined average blood selenium (0.043 microg/ml) and standard deviation (0.019 microg/ml), there was no obvious difference between each other (P > 0.05). The predictive risk degree (19.8%) is also similar to that of the Keshan disease occurrence (16.4%) of residents in Jilin province. The advance of the ecological risk assessment model of selenium offers a good example for the study on predictive models of other trace elements in the human body.

Ecotoxicity of Cadmium to Maize and Soybean Seedling in Black Soil

Ecotoxicity and bioavailability of cadmium (Cd) to the maize (Zea mays L.) and the soybean (Glycine max (L.) Merr.) were investigated by acute toxicity experiment in the laboratory with black soil. Ecotoxicity and bioavailability of Cd were quantified by calculating the median effective concentration (EC50) and bioaccumulation factor (BAF). The measurement endpoints used were seed germination and seedling growth (shoot and root). The results showed that concentrations of Cd in the soil had adverse effect on the growth of roots and shoots. Seed germination was not the sensitive indicator for the ecotoxicity of Cd in the soil, while the growth of roots was the most sensitive measurement endpoint. Absorbability and transport of Cd in plants depended on the test crop species and Cd concentrations in the soil. The maize retains more Cd in its roots, while the soybean transports more Cd to the shoots from roots.

Assessment of sustainable development system in Suihua City, China

Sustainable development is a complex and systemic issue. It is essential to study it by the component analysis method from the view of system science. The urban developmental sustainability is one of focuses that people has paid more attention to, however, little common understanding how to measure and evaluate the sustainability has been gotten. In this paper, a framework is designed to evaluate the developmental sustainability of Suihua City, Heilongjiang Province in China from the aspects of economy, society, population, resources and environment. We adopt the Principal Components Analysis (PCA) to decrease dimensions and simplify the original indexes into 12 indexes. Also, the hierarchy and comprehensive multiple-criterion evaluative methods are employed to assess the sustainable development system in Suihua City. Then, the weights of indexes are attained by Analytic Hierarchy Process (AHP) method. Furthermore, urban comprehensive development level, developmental sustainability, coordinate degree are calculated and analyzed. By analyzing, we know the fluctuation of development level of subsystem, especially resources and environment subsystem, is acute. The comprehensive development level of sustainable development system in Suihua has been on the rise since 1999. That results from the effect of traditional economic development mode with high energy-consumed being decreased in the city after 1999. At the same time, it is obvious that there was an instability of development level in Suihua City during 1990–2002, with a turn in 1998, and the development could be sustainable, the status trend was more harmonious in 1999–2002.