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741.
通过分析2002~2011年间陕西省建设用地和碳排放的变化,基于LMDI模型分解方法,探讨了10年间建设用地变化对碳排放增长的影响。结果表明:研究时序内,陕西省建设用地和碳排放量均呈增长态势,建设用地年扩展率1.25%,碳排放年均增长8.84%,建设用地变化与碳排放量正向效应显著,建设用地对碳排放的贡献度为12.36%,对建设用地采取总量控制原则,能有效控制碳排放量,对陕西省实现"十二五"期间碳减排目标具有重大意义。 相似文献
742.
研究并建立了利用TenaxGC管富集、热解吸仪脱附,经HP-5石英毛细管柱分离,气相色谱(具FID)测定空气,9--硫化碳的方法。研究结果为:当采集30L气体时,本方法检出限可达0.03mg/m3,监测浓度范围为0.03—14mg/m3,方法精密度为8.7%;样品在密闭、低温环境中可保存2d。该方法可以满足环境监测要求。 相似文献
743.
Organic Farming and Soil Carbon Sequestration: What Do We Really Know About the Benefits? 总被引:1,自引:0,他引:1
Organic farming is believed to improve soil fertility by enhancing soil organic matter (SOM) contents. An important co-benefit
would be the sequestration of carbon from atmospheric CO2. Such a positive effect has been suggested based on data from field experiments though many studies were not designed to
address the issue of carbon sequestration. The aim of our study was to examine published data in order to identify possible
flaws such as missing a proper baseline, carbon mass measurements, or lack of a clear distinction between conventional and
organic farming practices, thereby attributing effects of specific practices to organic farming, which are not uniquely organic.
A total of 68 data sets were analyzed from 32 peer-reviewed publications aiming to compare conventional with organic farming.
The analysis revealed that after conversion, soil C content (SOC) in organic systems increased annually by 2.2% on average,
whereas in conventional systems SOC did not change significantly. The majority of publications reported SOC concentrations
rather than amounts thus neglecting possible changes in soil bulk density. 34 out of 68 data sets missed a true control with
well-defined starting conditions. In 37 out of 50 cases, the amount of organic fertilizer in the organic system exceeded that
applied in the compared conventional system, and in half of the cases crop rotations differed between systems. In the few
studies where crop rotation and organic fertilization were comparable in both systems no consistent difference in SOC was
found. From this data analysis, we conclude that the claim for beneficial effects of organic farming on SOC is premature and
that reported advantages of organic farming for SOC are largely determined by higher and often disproportionate application
of organic fertilizer compared to conventional farming. 相似文献
744.
Spatial Distribution and Temporal Change of Carbon Storage in Timber Biomass of Two Different Forest Management Units 总被引:2,自引:0,他引:2
Forests make up large ecosystems and can play an important role in mitigating the emissions of CO2, the most important greenhouse gas. However, they are sources of atmospheric carbon when they are disturbed by human or natural
causes. Storage of carbon through expansion and adaptive management of forest ecosystems can assist in reducing carbon concentrations
in atmosphere. This study proposes a methodology to produce spatially explicit estimates of the carbon storages (aboveground
plus belowground) depending on land use/cover changes in two different forest ecosystems during various periods. Carbon storages
for each forest ecosystem were projected according to inventory data, and carbon storages were mapped in a geographic information
system (GIS). Results showed that total carbon stored in above and belowground of both forest ecosystems increased from one
period to other because of especially increase of productive forest areas and decline of degraded forest areas as well as
protection of spruce forests subject to insect attacks. 相似文献
745.
Kazuya Goto Hiromichi Okabe Firoz Alam Chowdhury Shinkichi Shimizu Yuichi Fujioka Masami Onoda 《International Journal of Greenhouse Gas Control》2011,5(5):1214-1219
In order to establish energy-saving technology for CO2 capture from blast furnace gas, novel absorbents were developed in the laboratory and evaluated at a 1 tCO2/d test plant. At first, CO2 absorption and desorption behaviors of single-component amine solvents for simulated blast furnace gas (CO2/N2 = 20%/80%) were investigated through a screening test using a small scrubbing bottle. These amine solvents were additionally analyzed using nuclear magnetic resonance (13C NMR) spectroscopy and reaction calorimetry. The results of the laboratory experiments showed that there was a trade-off between absorption rate and enthalpy of absorption but some absorbents had unique features. For example, 2-isopropylaminoethanol (IPAE) had high absorption rate and small enthalpy of absorption. Then, new IPAE-based amine solvents (RITE solvents: RITE-A and RITE-B) were formulated and evaluated at the 1 tCO2/d test plant. CO2 regeneration energies of the RITE solvents were 3.3 and 3.1 GJ/tCO2, respectively. With certain process conditions and plant specifications optimized, RITE-B was estimated to have the potential to achieve 2.5 GJ/tCO2. 相似文献
746.
Stefan Giljum Eva BurgerFriedrich Hinterberger Stephan LutterMartin Bruckner 《Resources, Conservation and Recycling》2011,55(3):300-308
Many of today's most urgent environmental problems arise from increasing volumes of worldwide production and consumption and the associated use of natural resources, including renewable and non-renewable raw materials, energy, water and land. Solid indicators to measure different dimensions of anthropogenic resource use are essential for designing appropriate policy measures for a sustainable management of these resources. Based on a brief review of the current state of the art of resource use indicators, this paper suggests a new set of complementary resource use indicators, combining existing measures for resource use. The suggested indicator set covers the core resource input categories of materials, water and land area and includes the output category of greenhouse gas emissions. This set can be applied consistently from the micro level of products and companies up to the macro level of countries and world regions. All suggested indicators take a life-cycle wide perspective on production and consumption activities. This set of indicators deals with the issue of the overall scale of the human production and consumption system. It can be regarded as the general indicator framework, based on which more specific indicators, for example, on different environmental impacts related to natural resource use, can be calculated. 相似文献
747.
选取苯系物中的代表性组分苯、甲苯和二甲苯等化合物,通过热脱附、气相色谱质谱条件的优化及方法学考察,建立了热脱附进样-气相色谱-同位素比值质谱(GC-C-IRMS)测定苯系物单体碳同位素比值的方法。结果表明,单体化合物进样量在0.3μg以上均能满足测定要求;与直接进样方式相比,热脱附进样对单体碳同位素比值测定无分馏影响;标准溶液和苯系物土壤样品测定结果的RSD分别为1.0%~1.7%和0.3%~2.6%。 相似文献
748.
济南市环境空气中PM_(2.5)的碳组成与特征分析 总被引:3,自引:0,他引:3
对济南市环境空气中PM2.5中碳组分污染特征的研究结果表明,济南市环境空气细颗粒物中碳主要以有机碳(OC)和元素碳(EC)的形式存在,二者浓度以冬季最高,且变化趋势相同;OC占总碳比例较高;冬季二次有机气溶胶(SOC)浓度最高,与污染源排放及气象条件有关。 相似文献
749.
<正>Nanoparticles(NPs)from anthropogenic sources have applications in several commercial products,including cosmetics,pharmaceuticals,and materials.There is evidence that during their usage and disposal,engineered nanoparticles can and will be released into wastewater(Gottschalk et al.,2013;Pasricha et al.,2012;Westerhoff et al.,2013;Zheng et al.,2015).If water and wastewater treatment plants are inefficient or incapable of removing NPs from water,NPs will be released with the treated effluent,entering drinking water sources and natural aquatic environments,increasing exposure for plants,microorganisms, 相似文献
750.
Policy-makers are interested in cost-effective and socially acceptable ways of encouraging the public to adopt more environmentally-friendly lifestyles. One area which UK policy-makers are focussing on is ‘catalyst behaviour’, the notion that taking-up a new behaviour (such as recycling) may cause people to adopt other pro-environmental behaviours. Yet, evidence for such ‘spill-over’ effects is so far limited, and it is unclear when and how cross-situational motivations (e.g., pro-environmental identity) may predict behaviour and when contextual factors are more important. We report on a postal survey (N = 551) of pro-environmental behaviours amongst the UK public. We assess the influence of pro-environmental self-identify on consistency across a range of behaviours. Pro-environmental values, perceived behavioural control, subjective norm, attitudes, and demographic factors were also measured. Findings show self-identity to be a significant behavioural determinant over and above theory of planned behaviour variables for carbon offsetting behaviour. However, pro-environmental self-identity was only a significant predictor for certain other pro-environmental behaviours; background variables were also important predictors. Limitations of the study, and implications for theory and policy, are discussed. 相似文献