The leaf-air transfer of organochlorine pesticides (OCPs) in three kinds of vegetables, namely lettuce, romaine and garlic leaves was investigated. It was found that although the uptake of OCPs by the three selected vegetables was similar under controlled conditions, the depuration varied significantly among chemicals and plant species in terms of elimination rate, final residue of each OCPs, as well as the effect of temperature on the residue of OCPs in the vegetables. The results indicated that neither QCB nor HCB could be trapped tightly by any of the three selected vegetables, in contrast, p,p'-DDT could be retained effectively by all of them; the retainment of alpha-HCH, gamma-HCH, p,p'-DDE, was dependent on the vegetable species, of which the garlic leaf had the biggest ability to trap them. Our work provided insight into the behavior of OCPs in the agroecosystem. 相似文献
The effect of chlorpyrifos added in irrigation water to a red soil from Central South China on the growth of wheat and oilseed rape seedlings, together with its uptake, was studied in a pot experiment. Addition of chlorpyrifos (1-10 microg g-1) in a single irrigation with distilled water resulted in absorption of chlorpyrifos by wheat (0.257-4.50 microg g-1) and also oilseed rape seedlings (0.249-2.02 microg g-1) during 20 d of plant growth. An initial concentration of chlorpyrifos in soil that is equivalent to or below 10 microg g-1 did not significantly influence the growth of wheat seedlings. Similarly, an initial concentration equivalent to or below 5 microg g-1 did not significantly influence the growth of oilseed rape seedlings. The degradation rate of chlorpyrifos was 1.4-4.2 times larger in oilseed rape rhizosphere soil than in unvegetated soil. The numbers of bacteria and fungi in oilseed rape rhizosphere soil were 3.18 times and 1.84 times larger, respectively, than those in unvegetated soil. This helps to explain the difference in degradation rates obtained. 相似文献
Based on the theory of ecological footprint this paper analyzed the ecological economic system in Funing County in the view
of demands of economic system to natural resource and supply of ecosystem for natural resources. It was proposed that the
concept of ecological deficit (ecological remainder) per ten thousands yuan GDP be used to evaluate development of ecological
economic system. With a synthesis appraisement to the ecological economic system using entire-array-polygon method combined
with Ulanowicz development ability and with ecological deficit (ecological remainder) per ten thousands yuan GDP, it provids
a theoretical base for reconstructing and managing of demonstration eco-region. 相似文献
China contributes 23 % of global carbon emissions, of which 26 % originate from the household sector. Due to vast variations in both climatic conditions and the affordability and accessibility of fuels, household carbon emissions (HCEs) differ significantly across China. This study compares HCEs (per person) from urban and rural regions in northern China with their counterparts in southern China. Annual macroeconomic data for the study period 2005 to 2012 were obtained from Chinese government sources, whereas the direct HCEs for different types of fossil fuels were obtained using the IPCC reference approach, and indirect HCEs were calculated by input-output analysis. Results suggest that HCEs from urban areas are higher than those from rural areas. Regardless of the regions, there is a similarity in per person HCEs in urban areas, but the rural areas of northern China had significantly higher HCEs than those from southern China. The reasons for the similarity between urban areas and differences between rural areas and the percentage share of direct and indirect HCEs from different sources are discussed. Similarly, the reasons and solutions to why decarbonising policies are working in urban areas but not in rural areas are discussed.
Environmental Science and Pollution Research - Morphological effect of bismuth vanadate (BiVO4) on visible light-driven catalytic degradation of aqueous paracetamol was carefully investigated using... 相似文献