Life cycle assessment of a pulverized coal power plant with post-combustion capture, transport and storage of CO2

In this study the methodology of life cycle assessment has been used to assess the environmental impacts of three pulverized coal fired electricity supply chains with and without carbon capture and storage (CCS) on a cradle to grave basis. The chain with CCS comprises post-combustion CO₂ capture with monoethanolamine, compression, transport by pipeline and storage in a geological reservoir. The two reference chains represent sub-critical and state-of-the-art ultra supercritical pulverized coal fired electricity generation. For the three chains we have constructed a detailed greenhouse gas (GHG) balance, and disclosed environmental trade-offs and co-benefits due to CO₂ capture, transport and storage. Results show that, due to CCS, the GHG emissions per kWh are reduced substantially to 243 g/kWh. This is a reduction of 78 and 71% compared to the sub-critical and state-of-the-art power plant, respectively. The removal of CO₂ is partially offset by increased GHG emissions in up- and downstream processes, to a small extent (0.7 g/kWh) caused by the CCS infrastructure. An environmental co-benefit is expected following from the deeper reduction of hydrogen fluoride and hydrogen chloride emissions. Most notable environmental trade-offs are the increase in human toxicity, ozone layer depletion and fresh water ecotoxicity potential for which the CCS chain is outperformed by both other chains. The state-of-the-art power plant without CCS also shows a better score for the eutrophication, acidification and photochemical oxidation potential despite the deeper reduction of SO_x and NO_x in the CCS power plant. These reductions are offset by increased emissions in the life cycle due to the energy penalty and a factor five increase in NH₃ emissions.     

Environmental and socioeconomic impacts of cobblestone quarries in Addis Ababa and implication for resource use efficiency,environmental quality,and sustainability of land after‐use

The extraction of construction material in Addis Ababa has been a source of public conflict for many years, especially in terms of quarry operation, displacement of people, rehabilitation of quarry sites, and land after‐use. One of the main reasons for the conflict has been the extraction sector's inability to adjust to the existing laws. This paper reports the findings of a study undertaken to assess the environmental and socioeconomic impacts of quarry mining in Addis Ababa, Ethiopia, and it prescribes interventions that can assist in mitigating the negative impacts of mining. Marked operational, environmental, and socioeconomic impacts have occurred as a result of cobblestone quarrying in Addis Ababa. Improvements in the mitigation of these impacts can be achieved if quarrying operations are planned prior to commencement; resource‐efficient and sustainable mining techniques are employed; stakeholder participation is enhanced; the government provides institutional, organizational, and technical support to the operators; regulations are improved and regulatory implementations receive strict follow‐up; and the provision of the Ethiopian constitution's regarding “rights to development” is respected.     

丹江口水库蓄水后汉江中下游水文时空变化的#br# 定量评估及其生态影响

采用变化范围法（RVA）定量研究了丹江口水库蓄水后汉江中下游水文情势的时空变化,评估出汉江干流变化度最大的江段和水文特征指标类别,分析了其对应的生态影响,并针对汉江流域的四大家鱼和水华问题进行了敏感水文指标的变化度分析。结果显示:丹江口大坝蓄水后,汉江下游河道流量是中变化度占主导,比例范围为47～63%;水位是高变化度占主导,襄阳站和皇庄站高变化度的水文指标所占比例远大于其它站点,依次为53% 和75%,各站水位较蓄水前下降了1～2 m。黄家港站高/低流量脉冲出现的频率减少（变化度为-0.49和 -0.62）,且持续的时间变短（变化度为-0.87和 -0.74）。皇庄站和襄阳站流量和水位的月均值和极值较蓄水前减少,逆转次数在高RVA范围内较蓄水前增加（变化度为1.82）。四大家鱼产卵的敏感水文指标出现频率较蓄水前减少,且为中高变化度。下游河道枯水期流量和水位减小,增加了水华发生几率。     

Evaluation of unmitigated options for municipal waste disposal site in Tehran,Iran using an integrated assessment approach

It can be difficult for assessors and decision-makers to compare different options for a project, and thus come to a reasoned and objective decision concerning the impacts and its sustainability at the local level. Therefore, using integrated assessment becomes crucially important for evaluating proposed different options. In this paper, we apply the Rapid Integrated Sustainability Assessment Method (RISAM) to evaluate the proposed unmitigated options for a municipal waste disposal site in Tehran, Iran. The results obtained showed that all of the alternative unmitigated options to the current method of open dumping were indicated as being consistent with very weak sustainability. The RISAM method demonstrated offers potential considerable benefits with respect to improved efficiency, reduced need for resources, and improved consistency and transparency in evaluation and reporting.     

Modeling the Effects of Tile Drain Placement on the Hydrologic Function of Farmed Prairie Wetlands

The early 2000s saw large increases in agricultural tile drainage in the eastern Dakotas of North America. Agricultural practices that drain wetlands directly are sometimes limited by wetland protection programs. Little is known about the impacts of tile drainage beyond the delineated boundaries of wetlands in upland catchments that may be in agricultural production. A series of experiments were conducted using the well‐published model WETLANDSCAPE that revealed the potential for wetlands to have significantly shortened surface water inundation periods and lower mean depths when tile is placed in certain locations beyond the wetland boundary. Under the soil conditions found in agricultural areas of South Dakota in North America, wetland hydroperiod was found to be more sensitive to the depth that drain tile is installed relative to the bottom of the wetland basin than to distance‐based setbacks. Because tile drainage can change the hydrologic conditions of wetlands, even when deployed in upland catchments, tile drainage plans should be evaluated more closely for the potential impacts they might have on the ecological services that these wetlands currently provide. Future research should investigate further how drainage impacts are affected by climate variability and change.     

Effects of Eastern Hemlock Decline on Large Wood Loads in Streams of the Appalachian Mountains

Evans, Daniel M., C. Andrew Dolloff, W. Michael Aust, and Amy M. Villamagna, 2012. Effects of Eastern Hemlock Decline on Large Wood Loads in Streams of the Appalachian Mountains. Journal of the American Water Resources Association (JAWRA) 48(2): 266‐276. DOI: 10.1111/j.1752‐1688.2011.00610.x Abstract: Eastern hemlock (Tsuga canadensis), a foundation species important to riparian forests of the Appalachian Mountains, is in decline due to the hemlock woolly adelgid (HWA) (Adelges tsugae). The effect of this insect on large wood (LW) production and recruitment to streams is largely unknown. We measured LW load, riparian forest composition, and T. canadensis health in 47 streams from Maine to Alabama and developed a conceptual model that frames the expected forest stand and instream LW response to the disturbance caused by HWA. In stands with HWA, 24.3% of the overstory T. canadensis basal area was stressed and 7.5% was dead, whereas only 3.0% was stressed and 2.0% was dead in stands without HWA. Mean T. canadensis effective LW load was 0.20 m³/100 m² in streams with adjacent stands infested by HWA, almost three times higher than in streams flowing through uninfested stands (p = 0.048). Higher frequencies of LW were found at streams with HWA present and there was a positive association between the percent of dead T. canadensis and T. canadensis LW load (ρ = 0.4468; p = <0.0001). Greater total LW loads were associated with higher stream gradients, lesser bankfull widths, and streams at lower latitudes. Our research supports the hypothesis that HWA infestation of T. canadensis in riparian forest stands has increased LW loads in streams. This episodic disturbance to the riparian forest overstory may have lasting impacts on aquatic ecosystem structure and function.     

Reducing environmental impacts through socioeconomic transitions: critical review and prospects

● Reducing environmental impacts through socioeconomic structural transitions. ● Simulation of looping the dynamic material cycle should be concerned. ● Transboundary effects of socioeconomic transitions need to be analyzed. ● Facilitating interregional cooperation and synergetic control mechanisms. Rapid socioeconomic development has caused numerous environmental impacts. Human production and consumption activities are the underlying drivers of resource uses, environmental emissions, and associated environmental impacts (e.g., ecosystem quality and human health). Reducing environmental impacts requires an understanding of the complex interactions between socioeconomic system and environmental system. Existing studies have explored the relationships among human society, economic system, and environmental system. However, it is unclear about the research progress in the effects of socioeconomic activities on environmental impacts and the potential directions of future research. This critical review finds that existing studies have identified critical regions, sectors, and transmission pathways for resource uses, environmental emissions, and environmental impacts from supply chain perspectives. Moreover, scholars have characterized the impacts of socioeconomic transitions on resource uses and environmental emissions. However, existing studies overlook the dynamic nature of the interconnections among human society, economic system, and environmental system. In addition, the effects of socioeconomic structural transitions on environmental impacts remain unknown. This review proposes four prospects and possible solutions that will contribute to a better understanding of the complex interactions among human society, economic system, and environmental system. They can help identify more effective solutions to reduce environmental impacts through socioeconomic transitions.     

Effects of two sludge application on fractionation and phytotoxicity of zinc and copper in the soil

The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and their phytotoxicity to pakchoi. The loamy soil was mixed with 0%, 20%, 40%, 60% and 80% (by weight) of digested sewage sludge (SS) and composted sludge (SC). The additions of both sludges caused a significant raise in all fractions, resulting in that exchangeable (EXCH) and organic bound (OM) became predominance of Zn and organic bound Cu occupied the largest portion. There was more available amount of Zn and Cu in SS treatments than SC treatments. During the pot experiment, the concentration of Zn in EXCH, carbonate (CAR) and OM and Cu in EXCH and OM fractions decreased in all treatments, so their bioavailability reduced. Germination rate and plant biomass decreased when the addition rate was high and the best yield appeared in 20% mixtures at the harvest of pakchoi. The two sludges increased tissue contents of Zn and Cu especially in the SS treatments. Zn in pakchoi was not only in relationship to ΔEXCH and ΔCAR forms but also in ΔOM forms in the sludge-soil mixtures. Tissue content of Cu in pakchoi grown on SC-soils could not be predicted by ΔEXCH. These correlation rates between Zn and Cu accumulation in pakchoi and variation of different fractions increased with time, which might indicate that sludges represented stronger impacts on the plant in long-term land application.     

Integrating Impacts into Adaptation Measures

A mechanism has been established to improve integration of international climate-related programmes. Known as the Climate Agenda it outlines a programme, that in a cost-effective way, responds to national obligations to respond to international agreements as well as their national needs for social and economic development. The paper briefly describes the Climate Agenda and the incorporation within it of studies of climate impact assessments and response strategies to reduce vulnerability. The need for increased emphasis on climate impact assessment and for the development of effective adaptation measures is emphasised following the elaboration of a Kyoto Protocol to the United Nations Framework Convention on Climate Change (UNFCCC). UNEP's efforts to identify national programmes contributing to the Climate Agenda are described.The response from developing countries has, however, been very disappointing, even from countries where we know work is ongoing through funding by GEF or US Country Studies Program and other bilateral programmes. Initial compilation of information available so far shows that many developed countries are putting a lot into the area of impact assessment of not just climate change, but also climate variability. There remain some research gaps, especially in the area of assessment of climate impacts on ecosystems, hydrological systems, etc. Considerable efforts are presently being directed at reduction of emissions of greenhouse gases and in the case of developing countries, most efforts are being directed towards completing national communications and providing baseline data for future studies.The paper refers to early activities by UNEP in cooperation with other international organizations to undertake integrated assessments of the impacts of climate change on important socio-economic sectors and the later incorporation of lessons learned into the IPCC Guidelines for Assessing Impacts of Climate Change.Later sections outline the development of a handbook on methods for climate change impact assessment and adaptation strategies as a practical approach to national assessments and the development of appropriate and cost-effective response to climate change.The initiation of a GEF-funded project to apply the methods contained in the handbook and improve the results based on national studies is also described for both developed and developing countries.Working in collaboration with a team of international experts under the coordination of the Institute of Environmental Studies at Vrije University (Amsterdam), the goal of this ongoing project is to develop a valuable methodological tool that Parties to the UNFCCC may apply to develop national climate change impact and adaptation assessments. Development of these guidelines was linked to a series of country studies in Antigua and Barbuda, Estonia, Cameroon and Pakistan funded under a UNEP/GEF project. The application of the first version of the UNEP Handbook by national study teams in these four countries is making valuable technical and practical contributions and will ensure that the next version of the Handbook will be a more useful tool for experts in developing countries undertaking similar studies in the future. The methods contained in the Handbook are also the basis for similar assessments funded under bilateral development programmes in other countries. These and similar studies elsewhere are coordinated with the UNEP programme and will eventually aim to create reliable and comparable assessments, a compatible set of tools for such purpose and the identification of realistic adaptation options for incorporation into national planning for adapting to climate change. The paper also addresses how climate impact assessment and response strategies are undertaken as part of national enabling activities carried out in co-operation with UNEP.     

累积影响监测系统初步设计

累积影响监测和适应性管理是减少和改善累积影响评价不确定性的重要途径之一。文章初步探讨了累积影响监测的概念,提出了累积影响监测系统的设计原则,从内容、时空范围、监测指标、监测结果的表达、实施机构、实施程序等多方面对累积影响监测系统进行了初步探讨。