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971.
Hawrot-Paw Małgorzata Koniuszy Adam Mikiciuk Małgorzata Izwikow Monika Stawicki Tomasz Sędłak Paweł 《Environmental science and pollution research international》2017,24(17):15022-15030
Environmental Science and Pollution Research - The purpose of this research was evaluation of the effect of soil contamination with waste coming from biomass gasification on chosen indicators of... 相似文献
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炼油化工废水处理的传统处理工艺中存在一定的弊端。为此,玉门炼油化工总厂对其废水处理设施进行了改建和扩建,其生物处理系统采用了序批式活性污泥法处理工艺。经过 3年运行的结果表明:该系统运行效果良好,处理后的水质可达到《GB8978-1996》(石化)一级排放标准的要求;化学需氧量(COD)和生化需氧量(BOD)分别降低78.6%和91.2%,硫化物去除率为98.2%,挥发酚去除率为99.6%。而且该反应器具有较强的耐冲击负荷能力,进水中COD在600 mg/L以下且有大幅度波动时,该系统仍可稳定地运行,处理后的水可达标排放。 相似文献
975.
Scale Effects on Spatially Varying Relationships Between Urban Landscape Patterns and Water Quality 总被引:2,自引:0,他引:2
Scientific interpretation of the relationships between urban landscape patterns and water quality is important for sustainable urban planning and watershed environmental protection. This study applied the ordinary least squares regression model and the geographically weighted regression model to examine the spatially varying relationships between 12 explanatory variables (including three topographical factors, four land use parameters, and five landscape metrics) and 15 water quality indicators in watersheds of Yundang Lake, Maluan Bay, and Xinglin Bay with varying levels of urbanization in Xiamen City, China. A local and global investigation was carried out at the watershed-level, with 50 and 200 m riparian buffer scales. This study found that topographical features and landscape metrics are the dominant factors of water quality, while land uses are too weak to be considered as a strong influential factor on water quality. Such statistical results may be related with the characteristics of land use compositions in our study area. Water quality variations in the 50 m buffer were dominated by topographical variables. The impact of landscape metrics on water quality gradually strengthen with expanding buffer zones. The strongest relationships are obtained in entire watersheds, rather than in 50 and 200 m buffer zones. Spatially varying relationships and effective buffer zones were verified in this study. Spatially varying relationships between explanatory variables and water quality parameters are more diversified and complex in less urbanized areas than in highly urbanized areas. This study hypothesizes that all these varying relationships may be attributed to the heterogeneity of landscape patterns in different urban regions. Adjustment of landscape patterns in an entire watershed should be the key measure to successfully improving urban lake water quality. 相似文献
976.
Ecotourism development is closely associated with the sustainability of protected natural areas. When facilitated by appropriate management, ecotourism can contribute to conservation and development, as well as the well-being of local communities. As such, ecotourism has been proposed and practiced in different forms in many places, including China. This study assesses ecotourism development at Xingkai Lake National Nature Reserve in Heilongjiang Province, China. Key informant interviews were conducted with representatives from the provincial Forestry Department, the Nature Reserve, and the local community. Observation was undertaken on three site visits and secondary data were collected. The potential for providing quality natural experiences is high and tourism development is occurring rapidly. However, current relationships between people, resources, and tourism have yet to provide mutual benefits necessary for successful ecotourism. The multi-stakeholder management style and the ambiguity of landownership within the nature reserve constitute structural difficulties for ecotourism management and operation. Although participation in ecotourism could provide a livelihood opportunity and interests in involvement in tourism have been identified among the local fishing community, current involvement is limited mainly due to the lack of mechanisms for participation. Therefore, it is recommended that management programs and government policies should be established to provide a platform for community participation in ecotourism. Then, a positive synergistic relationship between tourism, environment, and community could be developed. Planning and policy requirements are discussed for ecotourism development in protected areas in China. 相似文献
977.
利用美国环保局开发的新一代空气质量模式系统Models-3,对2010 年浙江省大气污染物进行数值模拟研究,并对SO2、NO2 和PM10 等大气污染物浓度的模拟结果与监测结果进行了对比分析。结果表明,Models-3 系统能较好地反映浙江省的大气污染情况,模拟值与观测值的变化趋势具有较好的一致性,说明该模式能较好地进行大气污染物的分布特征和变化规律的研究。为定量分析电力行业多污染物协同控制与区域复合型大气污染之间的定量关系,评估不同控制情景下的环境质量效益,应用CMAQ 空气质量模型分别对2010 年基准排放情景和火电行业主要污染物(SO2、NOx 和烟尘)的三套减排控制情景,评价环境空气污染物SO2、NOx、PM2.5 和PM10 状况进行模拟,评价污染物减排的环境效益。三套方案下PM2.5 浓度下降比例分别为0.53%、0.55% 和0.57%,其中重点区域浓度下降比例分别为4.36%、4.38%和5.9%;PM10 浓度下降比例分别为0.40%、0.42% 和0.65%,重点区域下降比例分别为3.42%、5.82% 和8.16%;NOx 浓度下降比例分别为12.4% 和13.3%,重点区域下降比例分别为13.8% 和16.9%;SO2 下降比例平均为11.24%,其中重点区域下降比例为14.4%。SO2、NOx 和烟(粉)尘协同减排对于浙江地区特别是重点区域的环境空气质量改善有着显著意义。 相似文献
978.
抽汲排液存在抽汲设备和工具密封性差,对井场环境污染比较严重的问题,为解决抽汲排液对井场造成的污染,分别对抽汲钢丝绳的选择、试油井口防喷盒的密封以及试油抽汲作业规程及其它方面作了研究和应用,使抽汲排液对井场造成的污染得到了较好控制,符合新疆油田创建"绿色油气田"的要求。 相似文献
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微量元素对双孢蘑菇菌丝生长的影响 总被引:3,自引:0,他引:3
聋用固体平板和液体摇瓶培养试验方法,研究了Zn2+、Cu2+、Co2+、Mo(VI)、Mn2+等5种微量元素对双孢蘑菇2796菌丝生长的影响。通过测定各处理组的菌丝干重、胞内多糖、过氧化物酶活和菌丝生长势等生长参数表明,双孢蘑菇在添加上述5种浓度为20—40mg/L的微量元素时,对菌丝生长势、胞内多糖量和胞外蛋白量等都有促进作用,加入的浓度不同其促进程度也不同。加入Mn2+促进菌丝生长的效果最明显,使菌丝干重达最高值(200mg/100ml),胞内多糖量高达23mg/100ml,分别比对照组增加200%和400%,但添加高浓度的微量元素则会抑制菌丝的生长。 相似文献