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对环境信息的定义进行了表述。环境信息具有空间性、时间性、整体性、科学性、不确定性的特点,可用系统法、用途法和公开法进行分类。环境信息公开中的环境信息经过收集、评估、整理、分析、公开(传播)、使用六个环节形成环境信息循环。 相似文献
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Chen Yang Li Peijun Carlo Lupi Sun Yangzhao Xu Diandou Feng Qian Fu Shasha 《Waste management (New York, N.Y.)》2009,29(6):1996-2004
This paper discusses actions aimed at sustainable management of healthcare wastes (HCW) in China, taking into account the current national situation in this field, as well as the requirements deriving from the Stockholm Convention on Persistent Organic Pollutants and the WHO recommendations. By the end of 2005, there were 149 low-standard HCW disposal facilities in operation in China, distributed throughout different areas. According to the National Hazardous Waste and Healthcare Waste Disposal Facility Construction Plan, 331 modern, high-standard, centralized facilities will be built up in China in municipal level cities. Although incineration is still the main technical option for HCW disposal in China, it is expected that, especially for medium and small size facilities, non-incineration technologies will develop quickly and will soon become the main technical option. The basic management needs – both from the point of view of pollution control and final disposal – have been defined, and a system of technical and environmental standards has been formulated and implemented; however, there are still some shortages. This is particularly true when considering the best available techniques and best environmental practices developed under the Stockholm Convention, with which the present technological and managing situations are not completely compliant. In this framework, the lifecycle (from generation to final disposal of wastes) of HCW and holistic approaches (technology verification, facilities operation, environmental supervision, environmental monitoring, training system, financial mechanism, etc.) towards HCW management are the most important criteria for the sustainable and reliable management of HCW in China. 相似文献
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Adsorption of lambda-cyhalothrin and cypermethrin on two typical Chinese soils as affected by copper
Jun Liu Xiaomeng Lü Jimin Xie Yafei Chu Cheng Sun Qian Wang 《Environmental science and pollution research international》2009,16(4):414-422
Background, aim, and scope Pesticides and heavy metals pollution in soil environment has become a serious problem in many countries including China.
Repeated applications of bordeaux mixture (a blend of copper sulfate and calcium hydroxide) and pyrethroid (Pys) insecticides
have led to elevated copper (Cu) and Pys concentrations in vineyard surface soils. However, few studies focused on the interaction
of Pys and heavy metals in the soil environment. Our previous studies had indicated the combined effect of cypermethrin (CPM)
and Cu on soil catalase activity. Also, we had suggested that the addition of Cu could catalyze photo-degradation of CPM and
lambda-cyhalothrin (λ-CHT) in aqueous solution and restrain their degradation in soil. To better understand the potential
influence of Cu on the fate of Pys in the soil environment, the aim of the present work was to examine the effect of Cu on
the adsorption of λ-CHT and CPM on two typical Chinese soils with different soil characteristics, which was one of the key
processes controlling the fate of Pys, and to provide more information about the potential ecological risk of chemicals on
the soil ecosystem. Fourier transform infrared and point charges analysis using the MOPAC program of the Gaussian system were
also used to reveal the probable adsorption mechanism of λ-CHT and CPM on soils.
Materials and methods Two vineyard soils with different properties were chosen as experimental samples. They were sampled from 0 to 10 cm, dried,
and sieved to 2 mm. Each soil was spiked with copper sulfate solution to obtain the following total soil Cu concentrations:
100, 200, 400, 800, and 1,600 mg·kg−1. The treated soils were incubated for 2 weeks and then dried at 20°C. For each soil sample and at each soil Cu concentration,
the adsorption of λ-CHT and CPM was measured using a batch equilibrium method. The concentration of λ-CHT was determined by
HPLC, and the amount of λ-CHT and CPM adsorbed by the soil sample at equilibrium was determined by the difference between
the initial and equilibrium concentrations in solution corrected by the blank adsorption measurement.
Results Without the addition of Cu, the adsorption of λ-CHT and CPM on Black soil is greater than that on Red soil, while the adsorption
of λ-CHT on both soils is significantly stronger than that of CPM. As the soil Cu concentration increased from 19 (or 18;
background) to 1,600 mg·kg−1, the adsorption coefficient (K
d) of λ-CHT decreased from 12.2 to 5.9 L·kg−1 for Red soil, and from 26.1 to 16.8 L·kg−1 for Black soil, whereas the CPM adsorption coefficient in both soils decreased nearly by 100% (K
d decreased from 9.4 to 0.2 L·kg−1 for Red soil and from 16.2 to 0.5 L·kg−1 for Black soil).
Discussion Pys adsorption is a surface phenomenon which depends on the surface area and the organic matter content. Thus, the Black soil,
having higher organic matter and greater surface area than that of the Red soil, show greater adsorption affinity to λ-CHT
and CPM. In our study, the different adsorption affinity of the two Pys was obtained, which was probably attributed to differences
with respect to their physical–chemical properties. Further comparison upon the two Pys was conducted. The point charges of
halogen atoms in the λ-CHT and CPM were calculated, the differences of which probably lead to the fact that λ-CHT has a stronger
binding capacity to soils than CPM. Also, FTIR spectra show that competitive adsorption occurs between CPM and Cu for the
same adsorption sites, which is responsible for the obtained suppression of CPM adsorption affected by Cu.
Conclusions Lambda-cyhalothrin shows a significantly stronger adsorption than cypermethrin on both soils. This phenomenon may be due to
several reasons: (1) λ-CHT has lower solubility and a higher octanol–water partition coefficient value than CPM; (2) λ-CHT
consists of specific isomers, whereas CPM is mixtures of eight different isomers; (3) the chlorine and fluorine atoms in the
λ-CHT have a negative point charge, whereas the chlorine atoms in the CPM have a positive point charge. As the soil Cu concentrations
increased from 19 (or 18) mg·kg−1 to 1,600 mg·kg−1, the adsorption coefficient of λ-CHT and CPM decreased on both soils. This is mainly due to a competition between Cu and
Pys for occupying the adsorption sites on soils. The information from this study have important implications for vineyard
and orchard soils, which often contain elevated levels of Cu and Pys. These results are also useful in assessing the environmental
fate and health effect of λ-CHT and CPM.
Recommendations and perspectives It is important for environmental scientists and engineers to get a better understanding of soil–metal–organic contaminant
interactions. However, pesticide adsorption involves complex processes, and shortcomings in understanding them still restrict
the ability to predict the fate and behavior of pesticide. Therefore, considerable research should be carried out to understand
the mechanism of interaction between Pys and heavy metal on soils clearly. 相似文献
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