中国环境影响评价管理的现状、问题及展望

文章在客观分析中国环境影响评价的发展历史、现有法规体系、管理体制和主要成绩的基础上,指出了环境影响评价管理中存在的规划环评滞后、监管环节薄弱、公众参与不足以及队伍能力欠缺等主要问题。结合中国环境影响评价管理的特点和相关领域的发展变化,对未来环境影响评价工作的开展进行了展望。认为应该重点加强四个方面的工作,即通过确立环境目标来促进经济增长方式的转变,通过完善空间规划体系为规划环评提供基本依据,通过加强环境监管来促进环保措施落实,通过加强队伍能力建设来提高环评质量。     

Effects of the "Conversion of Cropland to Forest and Grassland Program" on the water budget of the Jinghe River catchment in China

In 1999 China adopted the "Conversion of Cropland to Forest and Grassland Program" (CCFGP), a nationwide ecological recovery program, to minimize wide-scale soil erosion and vegetation degradation in China, as well as to improve water budgeting results. In the 10 yr since implementation, the CCFGP has resulted in the recovery and reforestation of >100,000 km of cropland and bare land, though the quantitative effect of this program on catchment water budget is not entirely clear. Therefore, we used the Soil and Water Assessment Tool to evaluate and quantify the effects of the CCFGP on the water budget of the Jinghe River catchment, a tributary of the Yellow River covering the central region of the Loess Plateau. Our results indicated that precipitation had dropped by 12.0% from the 1970s (611.6 mm) to the 2000s (538 mm) and that there was a corresponding 25.2% decrease in humidity index from 0.48 to 0.36. Before the CCFGP's implementation, forest and grassland had been decreasing, while bare land, cropland, and shrub land had been increasing. After the implementation of the CCFGP, the opposite trend was observed. Moreover, streamflow increased by about 15 and 20% for the upstream and middle stream subbasins, respectively, while soil water content also showed an obvious increase. Over the same period, evapotranspiration decreased by 5.2 and 13.5 mm and runoff decreased by 37.5 and 38.6% in the two subbasins. The same trends were obtained in the downstream subbasin, where changes were even greater. As a result of the reduced runoff and evapotranspiration, utilization of water resources was more efficient and ecological environment was improved under the CCFGP policy. Our results indicate the CCFGP resulted in a favorable ecological impact and should therefore be maintained.     

季节性雪被对青藏高原东缘高寒草甸土壤氮矿化的影响

依据自然雪被分布的差异,在青藏高原东缘高寒草甸中设置3条样带(即深雪、中等厚度雪被和浅雪),于2008年的秋冬过渡期,连续监测各样带中的雪被厚度和土壤温度,并采用原位培养法测定每月的土壤氮素氨化、硝化和矿化速率,以研究不同厚度雪被对高寒草甸土壤氮矿化的影响.结果表明,月均土温、每月日最高土温均值分别与雪被厚度极显著相关,二次函数关系拟合较好(R2=0.576,0.685),且根据每月日最高土温均值与雪被厚度的二次函数关系方程可知,25 cm厚的雪被可以起到较好的隔绝效果;土壤含水量受雪被厚度和土壤温差两个因素的显著影响.在秋冬过渡期末,浅雪梯度下土壤硝态氮含量显著降低,且雪被下的净氮矿化速率与月均土温、每月日最高土温均值、每月日最低土温均值都分别呈极显著相关,二次函数关系拟合较好(R2=0.589,0.541,0.601).研究表明,不同厚度的雪被对土壤温度和含水量影响显著,从而显著地影响着土壤氮的矿化,深雪更有利于氨化、硝化和氮矿化.图7表2参36     

(N-[2-(2-氧-1-咪唑烷基)乙基]-N '-苯基脲(EDU)对环境臭氧胁迫下的水稻和小麦生长的影响

通过对作物定期喷施不同浓度(0、150、300和450 mg·L-1)的N-[2-(2-氧-1-咪唑烷基)乙基]-N'-苯基脲(ethy lenediurea,EDU)溶液,研究EDU对环境O3胁迫下水稻“粤晶丝苗2号”(Oryza sativa L.Yuejingsi 2)和小麦“北农9549”(Triticum a...     

硫酸锰废渣浸出液对斑马鱼的毒性及抗氧化酶活性的影响

已有研究表明,堆积在湘西花垣河河岸的硫酸锰废渣含有多种重金属,可能是导致花垣河河水和沉积物重金属污染的主要原因.为了评价硫酸锰废渣的潜在生态风险和对水生动物的毒性,本研究分析了硫酸锰废渣浸出液中的主要重金属成分,用漫出液对斑马鱼进行了急性毒性实验,观察在急性胁迫下斑马鱼的体征变化,测定了斑马鱼在亚致死浓度下的生化指标的...     

Matrix-bound phosphine and phosphorus fractions in paddy soils

Phosphine (PH(3)) is a natural gaseous carrier of phosphorus (P) in its geochemical cycles, and it might be important to the P balance of natural ecosystems. Paddy fields are thought to be one of the main sources responsible for the production and emission of PH(3) in to the environment. The relationships between matrix-bound PH(3) (MBP) and different P fractions, as well as selected metals were investigated to explore the possible production of MBP and its link to P cycle in the paddy soils. MBP range from 20.8 (-1) to 502 ng kg(-1) with an average of 145 ng kg(-1). Concentrations at the milk stage are significantly higher than at the jointing stage. The total P range from 333 mg kg(-1) to 592 mg kg(-1). Average P fractions decrease in the order: Ca-P (69.9%) > Organic P (16.5%) > occluded P (6.50%) > Fe-P (5.93%) > dissolved P (0.80%) > exchangeable P (0.32%) > Al-P (0.02%). Different levels of nitrogen fertilizer have little effect on the contents of MBP, P fractions and metals. A significant positive correlation between MBP and Ca-P (p = 0.002), as well as between MBP and Ca (p = 0.008) could be observed, suggesting that Ca-P mainly affects the production of MBP in the paddy soils. It is suggested that soil MBP is strongly linked to Ca-P fertilizer use because soil spiked with P-fertilizer produced an additional 758 ± 142 ng of MBP per kg of soil, compared to only 81.7 ± 12.3 ng of MBP per kg of unspiked soil. No correlations are found between MBP and other P fractions, or between MBP and Al, Fe and Mn.     

Fabrication and characterization of lightweight aggregate prepared from steel mill sludge in one step

Journal of Material Cycles and Waste Management - The qualified green lightweight aggregate (LWA) was successfully prepared from steel mill sludge (SMS) and fly ash (FAS) in one step using the...     

制度与市场机制在治理污染中的作用

寻找一种既能促进经济发展又能保护环境的控制环境污染的有效途径具有十分重要的意义。新制度经济理论为环境污染的控制及其政策的制定提供了理论基础。该理论认为,当传统的管制方法不能实现资源最优配置的时候,通过界定产权和进行产权交易的方法是可以得到满意结果的。     

排污权交易是控制环境问题的一种有效途径

排污权交易是解决环境外部不经济性的手段,与传统的控制环境问题手段相比,它具有在确保环境质量目标的前提下,以控制环境污染成本最小化实现资源最优配置的优点,符合我国国情,是我国控制环境问题的有效途径。     

黄淮海湿地系统典型挺水植物对水华藻类的化感效应

利用植物的化感作用可抑制有害藻类生长,控制水华发生,改善水质.文章在考察黄淮海湿地系统的基础上,选取典型挺水植物菖蒲(Acorus calamus)和香蒲(Typha latifolia),用0.1×Hoagland完全培养液进行种植,利用其种植水培养湿地典型水华藻类--铜绿微囊藻(Microcystis aeruginosa Kütz)和鱼腥藻(Anabeana Bory),研究菖蒲和香蒲的种植水对铜绿微囊藻和鱼腥藻生长的影响,评价挺水植物对水华藻类的化感效应.结果显示:菖蒲种植水对铜绿微囊藻的抑制作用较强;而香蒲种植水对鱼腥藻的抑制作用较强,但是对铜绿微囊藻的生长却有促进作用.结果表明两种挺水植物的种植水都含有影响水华藻类生长的化感物质.进一步的研究表明,两种植物种植水对以上两种藻类生长的影响具有显著的体积比浓度效应.因此,保护和恢复湿地挺水植物群落对改善水环境具有重要作用,但利用挺水植物化感效应进行水体环境净化时,应按水体中有害藻类的类型合理选择植物种类.