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411.
Wenying Chen Yves-Michel Le Nindre Ruina Xu Delphine Allier Fei Teng Kim Domptail Xing Xiang Laura Guillon Jiyong Chen Lingyan Huang Rongshu Zeng 《International Journal of Greenhouse Gas Control》2010,4(2):341-350
A method, based on spatial analysis of the different criteria to be taken into consideration for building scenarios of CO2 capture and storage (CCS), has been developed and applied to real case studies in the Hebei province. Totally 88 point sources (42 from power sector, 9 from iron and steel, 18 from cement, 16 from ammonia, and 3 from oil refinery) are estimated and their total emission amounts to 231.7 MtCO2/year with power, iron and steel, cement, ammonia and oil refinery sharing 59.13%, 25.03%, 11.44%, 3.5%, and 0.91%, respectively. Storage opportunities can be found in Hebei province, characterised by a strong tectonic subsidence during the Tertiary, with several kilometres of accumulated clastic sediments. Carbon storage potential for 25 hydrocarbon fields selected from the Huabei complex is estimated as 215 MtCO2 with optimistic assumption that all recovered hydrocarbon could be replaced by an equivalent volume of CO2 at reservoir conditions. Storage potential for aquifers in the Miocene Guantao formation is estimated as 747 MtCO2 if closed aquifer assumed or 371 MtCO2 if open aquifer and single highly permeable horizon assumed. Due to poor knowledge on deep hydrogeology and to pressure increase in aquifer, injecting very high rates requested by the major CO2 sources (>10 MtCO2/year) is the main challenge, therefore piezometry and discharge must be carefully controlled. A source sink matching model using ArcGIS software is designed to find the least-cost pathway and to estimate transport route and cost accounting for the additional costs of pipeline construction due to landform and land use. Source sink matching results show that only 15–25% of the emissions estimated for the 88 sources can be sequestrated into the hydrocarbon fields and the aquifers if assuming sinks should be able to accommodate at least 15 years of the emissions of a given source. 相似文献
412.
Renbin Zhu Yashu Liu Hua Xu Tao Huang Jianjun Sun Erdeng Ma Liguang Sun 《Atmospheric environment (Oxford, England : 1994)》2010,44(3):304-311
During the summertime of 2007/2008, carbon dioxide (CO2) and methane (CH4) fluxes across air–water interface were investigated in the littoral zones of Lake Mochou and Lake Tuanjie, east Antarctica, using a static chamber technique. The mean fluxes of CO2 and CH4 were ?70.8 mgCO2 m?2 h?1 and 144.6 μgCH4 m?2 h?1, respectively, in the littoral zone of Lake Mochou; The mean fluxes were ?36.9 mgCO2 m?2 h?1 and 109.8 μgCH4 m?2 h?1, respectively, in the littoral zone of Lake Tuanjie. Their fluxes showed large temporal and spatial dynamics. The CO2 fluxes showed a significantly negative correlation with daily total radiation (DTR) and a weakly negative correlation with air temperature and water temperature, indicating that sunlight intensity controlled the magnitude of CO2 fluxes from the open lakes. The CH4 fluxes significantly correlated with local air temperature, water table and total dissolved solids (TDS), indicating that they were the predominant factors influencing CH4 fluxes. Summertime CO2 budgets in the littoral zones of Lake Mochou and Lake Tuanjie were estimated to be ?152.9 gCO2 m?2 and ?79.7 gCO2 m?2, respectively, and net CH4 emissions were estimated to be 312.3 mgCH4 m?2 and 237.2 mgCH4 m?2, respectively. Our results show that shallow, open, alga-rich lakes might be strong summertime CO2 absorbers and small CH4 emitters during the open water in coastal Antarctica. 相似文献
413.
Richard J. Brazee 《中国人口.资源与环境(英文版)》2010,8(3)
Chinese forest resources have become very scarce in the face of rapid economic growth demand, while the reform of collective forest right system is in full swing across the country. It will directly affect the regeneration level of forest resources and the diverse ecological value functions. In this article, the mainstream model paradigm of forest economics, that is, the basic framework of the Faustmann model and its evolution process are made in a more detailed explanation, especially the extended model in... 相似文献
414.
Crystal Gauvin Emi Uchida Scott Rozelle Jintao Xu Jinyan Zhan 《Environmental management》2010,45(3):488-501
The goal of this article is to understand strategies by which both the environmental and poverty alleviation objectives of
PES programs can be achieved cost effectively. To meet this goal, we first create a conceptual framework to understand the
implications of alternative targeting when policy makers have both environmental and poverty alleviation goals. We then use
the Grain for Green program in China, the largest PES program in the developing world, as a case study. We also use a data set from a survey
that we designed and implemented to evaluate the program. Using the data set we first evaluate what factors determined selection
of program areas for the Grain for Green program. We then demonstrate the heterogeneity of parcels and households and examine the correlations across households and
their parcels in terms of their potential environmental benefits, opportunity costs of participating, and the asset levels
of households as an indicator of poverty. Finally, we compare five alternative targeting criteria and simulate their performance
in terms of cost effectiveness in meeting both the environmental and poverty alleviation goals when given a fixed budget.
Based on our simulations, we find that there is a substantial gain in the cost effectiveness of the program by targeting parcels
based on the “gold standard,” i.e., targeting parcels with low opportunity cost and high environmental benefit managed by
poorer households. 相似文献
415.
416.
石油污染土壤原位生物修复的强化实验研究 总被引:2,自引:0,他引:2
为研究添加营养物质和高效降解石油微生物对油污土壤生物修复的作用,通过分层土柱的方法,连续监测了不同条件下不同土层的含水率、石油烃含量、细菌数量及脱氢酶活性。结果表明:添加营养物质同时接种高效微生物可使降解效果明显改善,降解率比在自然条件下提高近50%,而单纯添加营养物质不接种高效微生物可使降解率比在自然条件下提高约25%。降解初期,上层土壤降解效果较好,而到中后期,中下层降解效果好于上层。微生物数量和脱氢酶活性与石油降解率之间存在良好的相关性,脱氢酶活性比微生物数量更能反映修复过程中微生物的存活状态。添加营养物质和高效降解石油微生物对油污土壤原位生物修复具有强化作用。 相似文献
417.
418.
The combined effects of urea application and simulated acid rain on soil acidification and microbial community structure 总被引:2,自引:0,他引:2
Xingmei Liu Jian Zhou Wanlu Li Jianming Xu Philip C. Brookes 《Environmental science and pollution research international》2014,21(10):6623-6631
Our aim was to test the effects of simulated acid rain (SAR) at different pHs, when applied to fertilized and unfertilized soils, on the leaching of soil cations (K, Ca, Mg, Na) and Al. Their effects on soil pH, exchangeable H+ and Al3+ and microbial community structure were also determined. A Paleudalfs soil was incubated for 30 days, with and without an initial application of urea (200 mg N kg?1soil) as nitrogen (N) fertilizer. The soil was held in columns and leached with SAR at three pH levels. Six treatments were tested: SAR of pH 2.5, 4.0 and 5.6 leaching on unfertilized soil (T1, T2 and T3), and on soils fertilized with urea (T4, T5 and T6). Increasing acid inputs proportionally increased cation leaching in both unfertilized and fertilized soils. Urea application increased the initial Ca and Mg leaching, but had no effect on the total concentrations of Ca, Mg and K leached. There was no significant difference for the amount of Na leached between the different treatments. The SAR pH and urea application had significant effects on soil pH, exchangeable H+ and Al3+. Urea application, SAR treated with various pH, and the interactions between them all had significant impacts on total phospholipid fatty acids (PLFAs). The highest concentration of total PLFAs occurred in fertilized soils with SAR pH5.6 and the lowest in soils leached with the lowest SAR pH. Soils pretreated with urea then leached with SARs of pH 4.0 and 5.6 had larger total PLFA concentrations than soil without urea. Bacterial, fungal, actinomycete, Gram-negative and Gram-positive bacterial PLFAs had generally similar trends to total PLFAs. 相似文献
419.
Yun Kong Pei Zou Lihong Miao Jiaoqin Qi Liming Song Liang Zhu Xiangyang Xu 《Environmental science and pollution research international》2014,21(9):5983-5990
Bioremediation using isolated anti-cyanobacterial microorganism has been widely applied in harmful algal blooms (HABs) control. In order to improve the secretion of activated anti-cyanobacterial substances, and lower the cost, a sequential optimization of the culture medium based on statistical design was employed for enhancing the anti-cyanobacterial substances production and chlorophyll a (Chl a) removal by Streptomyces sp. HJC-D1 in the paper. Sucrose and KNO3 were selected as the most suitable carbon and nitrogen sources based on the one-at-a-time strategy method, and sucrose, KNO3 and initial pH were found as major factors that affected the anti-cyanobacterial ability of the isolated stain via the Plackett–Burman design. Based on the response surface and canonical analysis, the optimum condition of culture medium was obtained at 22.73 g l-1 of sucrose, 0.96 g l-1 of KNO3, and initial pH 8.82, and the Chl a removal efficiency by strain HJC-D1 increased from 63?±?2 % to 78?±?2 % on the optimum conditions. 相似文献
420.
CuO / 过硫酸氢钾体系催化氧化苯酚简 总被引:1,自引:0,他引:1
本论文通过直接沉淀法制备了CuO催化剂,结合过硫酸氢钾,在常温常压下催化氧化处理苯酚模拟废水。采用电子显微镜(SEM)、X射线粉末衍射(XRD)对催化剂进行了表征,并研究了反应过程中各影响因素对降解效率的影响。实验结果表明,在催化剂用量为0.2 g/L,氧化剂浓度为0.25 g/L,pH值为7,反应时间为60 min的条件下,浓度为50 mg/L的苯酚降解率可达100%,TOC去除率达84%。进一步实验表明,催化剂具有良好的重复使用能力。最后,通过自由基捕捉实验,考察了体系中的自由基种类,并根据实验结果,讨论了CuO/过硫酸氢钾体系的催化降解机理。 相似文献