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81.
建立反映环境成本和可持续发展的资源价格体系   总被引:4,自引:0,他引:4  
王玉庆 《环境保护》2005,(11):13-16
10月28日至29日,由国家发展改革委委员会主办的“资源价格改革研讨会”在钓鱼台国宾馆举行。中央政治局委员、国务院副总理曾培炎到会并致开幕辞,财政部、环保总局、国土资源部、水利部、科技部等部门,中石油、中石化等企业的多位高官也纷纷到会,并围绕“资源价格改革”这一内容发表了讲话。会上,王玉庆副局长代表国家环保总局发表了题为《建立反映环境成本和可持续发展的资源价格体系》的讲话,本刊在此全文发表讲话内容。[编者按]  相似文献   
82.
Increasingly, epidemiological evidences indicate chemosynthetic perfluorooctanoic acid (PFOA), an environmental pollutant, induces potential adverse effect on human health after long-term exposure. However, less study has been performed for assessment of acute effect of PFOA exposure on metabolic homeostasis. In experimental designs, PFOA-exposed liver cells in vivo and in vitro were used to discuss underlying mechanism related to PFOA-induced metabolic dysfunction. In serological tests, PFOA-exposed mice showed increased treads of liver functional enzymes in alanine transaminase (ALT), aspartate transaminase (AST), and total bilirubin (T-BIL), trypsinase, low density lipoprotein-cholesterol (LDL-C), and insulin, while blood glucose, high density lipoprotein-cholesterol (HDL-C), and glucagon levels were reduced. In histocytological observations, PFOA-exposed liver showed visible cytoplasmic vesicles, and intact pancreatic islets were observed in PFOA-exposed pancreas. Additionally, increased insulin-positive cells and reduced glucagon-positive cells were detected in PFOA-exposed islets. As shown in immunoassays, PFOA-exposed liver resulted in elevations of cluster of differentiation 36 (CD36)-labeled cells and CD36 protein. In mouse liver cell study, PFOA-exposed cells showed increased cell apoptotic count, and increased phosphorylated levels of Bcl-2 and Bad in the cells. Furthermore, PFOA-exposed liver cells exhibited elevations of CD36-labeled cells and CD36 protein. Taken together, the present data demonstrate that acute exposure to PFOA-impaired liver function is associated with inducting CD36 expression and apoptosis, as well as disrupting key hormones in the pancreas.  相似文献   
83.
Di(2-ethylhexyl) phthalate (DEHP) is an omnipresent environmental chemical with widespread nonoccupational human exposure through multiple ways. Although considerable efforts have been invested to investigate mechanisms of DEHP toxicity, the key metabolic biomarkers of DEHP toxicity remain to be identified. The aim of this study was to assess the urinary metabonomics of dietary DEHP in rats using the technique of ultra-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UPLC/Q-TOF-MS). Fourteen female Wistar rats were divided into two groups and given increasing dietary doses of DEHP for 30 consecutive days. The urinary metabolite profile was studied using ultra-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry. Principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) enabled clusters to be clearly separated. Eleven principal urinary metabolites were identified as contributing to the clusters. The clusters in the positive electrospray ionization (ESI) mode were xanthurenic acid, kynurenic acid, nonate, N6-methyladenosine, and L-isoleucyl-L-proline. The clusters in the negative ESI mode were hippuric acid, tetrahydrocortisol, citric acid, phenylpropionylglycine, cPA(18:2(9Z, 12Z)/0:0), and LysoPC(14:1(9Z)). The urinary metabonomic changes indicated that exposure to dietary DEHP can affect energy-related metabolism, liver and renal function, fatty acid metabolism, and cause DNA damage in rats. The findings of this study on the urinary metabolites and metabolic pathways of DEHP may form the basis for future studies on the mechanisms of toxicity of this commonly found environmental chemical.  相似文献   
84.
Plastic waste is a source of organic contaminants such as hexabromocyclododecanes (HBCDs). HBCDs have been found to cause developmental and reproductive toxicity; it is important to investigate the occurrence and metabolization of HBCDs in the soil environments with plastic waste contamination. This work analyzed HBCDs and their metabolites in soil and plant samples collected from Xinle and Dingzhou—the major plastic waste recycling centers in North China. Results showed that total HBCD concentrations in soils followed the order: plastic waste treatment site (11.0–624 ng/g) > roadside (2.96–85.4 ng/g) ≥ farmland (8.69–55.5 ng/g). HBCDs were detected in all the plant samples with total concentrations ranging from 3.47 to 23.4 ng/g. γ-HBCD was the dominant congener in soils, while α-HBCD was preferentially accumulated in plants. Compositions of HBCD isomers in soils and plants were significantly different (P < 0.05) among sampling sites and among plant species. HBCDs in farmland soil and all plant samples exhibited high enantio-selectivity based on the enantiomeric fractions (EFs). Furthermore, metabolites of pentabromocyclododecenes (PBCDEs) were frequently identified in soils, and mono-OH-HBCDs were the most common ones in plants. This study for the first time provides evidences of HBCD contamination in the soil-plant system caused by plastic waste, their stereo-selectivity, and metabolization behavior, improving our understanding of the environmental behavior and fate of HBCDs.  相似文献   
85.
As a primary factor responsible for lake eutrophication, a deeper understanding of the phosphorus (P) composition and its turnover in sediment is urgently needed. In this study, P species in surface sediments from a Chinese large eutrophic lake (Lake Taihu) were characterized by traditional fractionation and 31P nuclear magnetic resonance (NMR) spectroscopy, and their contributions to the overlying water were also discussed. Fractionation results show that NaOH-P predominated in the algal-dominated zone, accounting for 60.1% to total P in Zhushan Bay. Whereas, refractory fractions including HCl-P and residual-P were the main P burial phases in the macrophyte-dominated zone, the center and lakeshore. Recovery rates of the total P and organic P were greatly improved by using a modified single-step extraction of NaOH-EDTA, ranging from 22.6 to 66.1% and from 15.0 to 54.0%. Ortho-P, monoester-P, and pyro-P are identified as the major P components in the NaOH-EDTA extracts by 31P NMR analysis. Trace amount of DNA-P appeared only in sediments from algal- and macrophyte-dominated zones, ascribing to its biological origin. The relative content of ortho-P is the highest in the algal-dominated zone, while the biogenic P including ester-P and pyro-P is the highest in the macrophyte-dominated zone. Moreover, ortho-P and pyro-P correlated positively with TP and chlorophyll a in the overlying water, whereas only significant relationships were found between monoester-P, biogenic P, and chlorophyll a. These discrepancies imply that inorganic P, mainly ortho-P, plays a vital role in sustaining the trophic level of water body and algal bloom, while biogenic P makes a minor contribution to phytoplankton growth. This conclusion was supported by the results of high proportion of biogenic P in algae, aquatic macrophytes, and suspended particulate from the published literature. This study has significant implication for better understanding of the biogeochemical cycling of endogenous P and its role in affecting lake eutrophication.  相似文献   
86.
Environmental Science and Pollution Research - Rare earth elements (REEs) accumulate in the soil and ecosystem. Cerium (Ce) is one of the main additives in REE-containing fertilizers. However,...  相似文献   
87.
Environmental Science and Pollution Research - High-latitude coral communities have attracted much attention due to their potential as refuges during global climate change. However, this function...  相似文献   
88.

Net embodied petroleum importers face greater petroleum security risks in international trade due to their high foreign dependence. Therefore, paying better attention to the national flows and drivers of embodied petroleum consumption can effectively serve net embodied petroleum importers to avoid petroleum security risks and formulate environmental protection policy. This study utilized the multi-regional input–output model to determine the top five embodied petroleum net importers (i.e., the USA, Japan, Germany, the UK, and France) under the economic globalization, and traced the flows of embodied petroleum consumption through international trade. Combined with the logarithmic mean Divisia index method, this study also deeply investigated the drivers of changes embodied petroleum in net imports. The results show that from the perspective of international trade, the USA was not only the largest importer but also the largest exporter of embodied petroleum. Among the trade flows of embodied petroleum, the largest trade flow was from China to the USA, which indicated that China was the world factory and the USA was the consumer power. The embodied petroleum trade markets of Germany, the UK, and France was mainly distributed in Europe & Eurasia resulted from European economic integration. The largest contributor to the decrease of embodied petroleum imports in the top 4 net importers was the petroleum intensity effect. Meanwhile, the import dependence effect was the largest contributor to the increase of France’s embodied petroleum net imports. In order to further avoid the risk of petroleum security, it is an effective path worth exploring to construct the diversified petroleum product import strategy and improve energy efficiency.

  相似文献   
89.
Environmental Science and Pollution Research - Heavy metal input from the coastal urbanization and industrialization and their potential ecological risks have been a great concern in the northern...  相似文献   
90.
Environmental Science and Pollution Research - The use of cement and fly ash (FA) to prepare cemented tailings backfill (CTB) lowers backfill mining costs while also reducing pollution caused by...  相似文献   
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