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61.
An environmentally extended input-output (EE-IO) analysis - environmental impacts of material flows caused by the Finnish economy - was carried out in order to improve data on production and consumption in Finland. The study resulted in the ENVIMAT model, which can be used to analyze the relationship between material flows, environmental impacts and the economy. The model is based on monetary and physical input-output tables and an environmental life-cycle impact assessment. This article summarizes the main methodological aspects and findings regarding the material flows and climate impacts caused by the Finnish economy in 2002 and 2005. The Finnish model has relatively detailed input data with 150 industries and 918 products and the data on imports was assessed according to a mixed approach with the help of life-cycle inventory data. The results of the model showed that the Finnish economy uses imported material resources as much as domestic resources. Life-cycle greenhouse gas (GHG) emissions caused by imports were equivalent to 70-80% of domestic emissions. The GHG emissions embodied in imports (emissions abroad) and exports (emissions within Finland) were of the same magnitude. The analysis showed that the service sector accounted for 44% of GHG emissions caused by the domestic final use of products. Analysis of the results also showed that the indicator of total material requirement (TMR) should not be used for environmental impact comparisons of products and services. In the future, the aim is to use the ENVIMAT model for assessing temporal changes in the economy; for monitoring sustainable development; for planning climate change mitigation; and for identifying important factors in the economy and assessing their impacts.  相似文献   
62.
中国碳排放问题成为世界关注的焦点问题。研究碳排放与经济增长、能源消费关系有助于实现2020年碳减排目标。选取2001~2009年碳排放与能源消费、经济增长数据,运用灰色关联分析模型,分别计算碳排放与能源消费、经济增长的灰色关联度。研究结果表明,无论是从折线的相似程度还是相对于始点变化速率的接近程度来看,碳排放曲线与能源消费曲线、经济增长曲线十分相似,说明碳排放与能源消费、经济增长之间存在紧密联系。  相似文献   
63.
This study reviews the potential use of biochar as soil amendment in afforestation, reforestation, agroforestry, fruit tree orchards, and bio-energy plantations. Implementing this practice could sequester large amounts of carbon (C) over the long-term, potentially offsetting anthropogenic emissions of carbon dioxide, and mitigating climate change. On a global scale, this practice could sequester between 2 and 109.2 Pg biochar-C in 1.75 billion ha of degraded and deforested lands and agroforestry systems. An additional considerable amount could be sequestered in the soil of fruit tree orchards and bio-energy plantations. The anticipated improvement in the quality of the biochar-amended soils is expected to enhance resilience to these land uses, increasing their adaptation capacity to climate change. Yet, specific questions still need to be addressed, for example, the impact of biochar on the availability of nitrogen and potassium for plants in acidic soils and under humid conditions, as well as the impact of biochar on soil and trees in alkaline soils and under Mediterranean or drier conditions. Also, a full assessment of health hazards and environmental risks related to the production of biochar and its application in soil is required. Other questions relate to the environmental and economic costs of biochar application. Therefore, life cycle assessments and economic calculations should be conducted on a site-specific basis and include the practices of feedstock collection, transportation, processing, and spreading. International actions should regulate biochar practice as an eligible means for funding under the C finance mechanism. Specifically, payments should be provided to landowners for accomplishing ecosystem services.  相似文献   
64.
Emission allowances are sometimes distributed for free in an early phase of a cap-and-trade scheme to reduce adverse effects on the profitability of firms. This paper investigates whether grandfathering can also be used to avert the relocation of firms to countries with lower carbon prices. We show that under certain conditions, relocation can be averted in the long run, even if the grandfathering scheme is phased out over time and immediate relocation is profitable in its absence. This requires that the permit price triggers sufficient investments into low-carbon technologies or abatement capital that create a lock-in effect which makes relocation unprofitable.  相似文献   
65.
Solutions for conserving biodiversity lie in changing people's behavior. Ambitious international and national conservation policies frequently fail to effectively mitigate biodiversity loss because they rarely apply behavior-change theories. We conducted a gap analysis of conservation behavior-change interventions advocated in national conservation strategies with the Behavior Change Wheel (BCW), a comprehensive framework for systematically characterizing and designing behavior-change interventions. Using pollinator conservation as a case study, we classified the conservation actions listed in national pollinator initiatives in relation to intervention functions and policy categories of the BCW. We included all national-level policy documents from the European Union available in March 2019 that focused on conservation of pollinators (n = 8). A total of 610 pollinator conservation actions were coded using in-depth directed content analysis, resulting in the identification of 787 intervention function and 766 policy category codes. Overall, these initiatives did not employ the entire breadth of behavioral interventions. Intervention functions most frequently identified were education (23%) and environmental restructuring (19%). Least frequently identified intervention functions were incentivization (3%), and restriction (2%) and coercion were completely absent (0%). Importantly, 41% of all pollinator conservation actions failed to identify whose behavior was to be changed. Building on these analyses, we suggest that reasons for the serious implementation gap in national and international conservation policies is founded in insufficient understanding of which behavioral interventions to employ for most beneficial impacts on biodiversity and how to clearly specify the intervention targets. We recommend that policy advisors engage with behavior-change theory to design effective behavior-change interventions that underpin successful conservation policies.  相似文献   
66.
Global efforts to deliver internationally agreed goals to reduce carbon emissions, halt biodiversity loss, and retain essential ecosystem services have been poorly integrated. These goals rely in part on preserving natural (e.g., native, largely unmodified) and seminatural (e.g., low intensity or sustainable human use) forests, woodlands, and grasslands. To show how to unify these goals, we empirically derived spatially explicit, quantitative, area-based targets for the retention of natural and seminatural (e.g., native) terrestrial vegetation worldwide. We used a 250-m-resolution map of natural and seminatural vegetation cover and, from this, selected areas identified under different international agreements as being important for achieving global biodiversity, carbon, soil, and water targets. At least 67 million km2 of Earth's terrestrial vegetation (∼79% of the area of vegetation remaining) required retention to contribute to biodiversity, climate, soil, and freshwater conservation objectives under 4 United Nations’ resolutions. This equates to retaining natural and seminatural vegetation across at least 50% of the total terrestrial (excluding Antarctica) surface of Earth. Retention efforts could contribute to multiple goals simultaneously, especially where natural and seminatural vegetation can be managed to achieve cobenefits for biodiversity, carbon storage, and ecosystem service provision. Such management can and should co-occur and be driven by people who live in and rely on places where natural and sustainably managed vegetation remains in situ and must be complemented by restoration and appropriate management of more human-modified environments if global goals are to be realized.  相似文献   
67.
本文构建了多部门递归动态可计算一般均衡模型,考虑中国经济发展和碳减排的现实情况,以征收40元/吨碳税且无税收返还为基准情景,分析了碳税对中国经济和碳强度的影响;在此基础上,本文探讨六种税收返还情景(返还清洁能源部门部分碳税、返还服务业部分碳税、返还农村和城镇居民全部碳税、减免企业所得税、减免居民所得税、减免生产税)对碳税负效应的缓解作用,同时探讨税收返还政策下碳税对中国经济增长、社会福利、农村和城镇居民收入消费、各部门产出的影响差异,并从实现2020年和2030年减排目标的角度,比较不同返还情景下碳税对碳排放量、碳强度,以及对非化石能源占一次能源消费结构变化的长期影响。研究结果表明:基准情景下,碳税对经济确实存在负效应;六种返还政策均不同程度地降低碳税负效应,同时也能够保证实现2020年的减排目标且有利于实现2030年的目标;对单一部门(清洁能源部门或服务业)部分返还碳税能够促进相应部门的产出,但力度较小,与其他政策相比影响微弱,但都能够有效地促进这两大部门的发展,因此在制定补贴政策时应当考虑行业差异性,重点扶持符合绿色发展要求的行业;对农村和城镇居民的直接返还均能增加农村和城镇居民收入,刺激了消费进而带动社会经济发展,相比部门返还政策,这一政策更为有效的提高了社会福利,但也会进一步拉大农村与城镇居民之间的收入消费差距;减免企业所得税促进企业投资和产业结构调整;减免居民所得税极大的刺激居民消费;减免生产税促进进口、拉动就业率,降低化石能源部门产出,综合来看,相对于其他返还政策,减免生产税更有效可行。  相似文献   
68.
The paper reviews the current state of knowledge regarding sources of mercury emission in Poland. Due to the large quantities of coal burned at present, as well as taking into account existing reserves, coal remains the main energy source of energy in Poland. The data on coal consumption in Poland in the past, at present and in the future are discussed in the paper. Information on the content of mercury in Polish coals is presented.Coal combustion processes for electricity and heat production are the main source of anthropogenic mercury emission in Poland. It is expected that the current emissions will decrease in the future due to implementation of efficient control measures. These measures for emission reduction are described in the paper. Results of estimated mercury emission from coal-fired power station situated in the Upper Silesia Region, Poland are investigated. A relationship between mercury emission to the air and the mercury content in the consumed coal in power station equipped with the electrostatic precipitators (ESPs) is discussed.  相似文献   
69.
70.
This paper discusses some conceptual fundamentals for the derivation of environmental indicator sets. On the one hand, it defines requirements from environmental politics, environmental management and legislation, reaching from political target hierarchies and sustainable management strategies to holistic protection concepts such as process protection, resource preservation, ecosystem health and ecological integrity. On the other hand, demands from ecosystem theory are described which include the consideration of features such as self-organization, emergence, thermodynamics, gradients and ecological orientors in environmental indicator sets. From that concept, collective and emergent properties are selected and eight holistic ecosystem features are presented that indicate the ecosystemic state as an ensemble. These general indicators of ecosystem integrity are supplemented by variables on structural changes and substance dynamics.  相似文献   
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