An integrated assessment model of carbon sequestration benefits: a case study of Liping county, China

This research attempts to model the complexity of planting trees to increase China's CO(2) sequestration potential by using a GIS-based integrated assessment (IA) approach. We use the IA model to assess the impact of China's Grain for Green reforestation and afforestation program on farmer and state incomes as well as CO(2) sequestration in Liping County, Guizhou Province. The IA model consists of five sub-models for carbon sequestration, crop income, timber income, Grain for Green, and carbon credits. It also includes a complementary qualitative module for assessing program impacts by gender and ethnicity. Using four scenarios with various assumptions about types of trees planted, crop incomes by township, CO(2) credit prices, state subsidies, methods for estimating carbon sequestered, and harvesting of trees, we find great variation in the impact of the Grain for Green program on incomes and on carbon sequestered over a 48 year period at both the county and township levels.     

Competing conservation goals, biodiversity or ecosystem services: element losses and species recruitment in a managed moorland-bracken model system

Conservation management in Europe is often geared towards restoring semi-natural ecosystems, where the objective is to reverse succession and re-establish early-successional communities, to comply with national and international conservation targets. At the same time, it is increasingly recognised that ecosystems provide services that contribute to other, possibly conflicting policy requirements. Few attempts have been made to define these conflicts. Here, we assess some potential conflicts using a Calluna vulgaris-dominated moorland invaded by bracken (Pteridium aquilinum) as a model system, where the current policy is to reverse this process and restore moorland. We examined impacts of bracken control treatments on services (stocks and losses of C and mineral nutrients), litter turnover and biodiversity within a designed experiment over 7 years. Bracken litter was >2000 g m(-2) in untreated plots, and treatments reduced this quantity, and its element content, to varying degrees. Cutting twice per year was the most successful treatment in reducing bracken litter and its element content, increasing litter turnover, and increasing both mass and diversity of non-bracken vegetation. Diversity was greatest where bracken litter had been reduced, but species composition was also influenced by light sheep grazing. There was a significant loss of some chemical elements from bracken that could not be accounted for in other pools, and hence potentially lost from the system. In absolute terms large amounts of C and N were lost, but when expressed as a percentage of the total amount in the system, Mg was potentially more important with losses of almost a third of the Mg in the surface soil-vegetation system. There is, therefore, a potential dilemma between controlling a mid-successional invasive species for conservation policy objectives, especially when that species has evolved to sequester nutrients, and the negative effect of increasing environmental costs in terms of carbon accounting required, the potential input of nutrients to aquatic systems, and long-term nutrient loss. There is, therefore, a need to balance conservation goals against potential damage to biogeochemical structure and function.     

Impact of soluble organic matter and particulate organic matter on anammox system: Performance,microbial community and N2O production

In this study,the effects of soluble readily biodegradable COD (sCOD) and particulate slowly biodegradable COD (pCOD) on anammox process were investigated.The results of the longterm experiment indicated that a low sCOD/N ratio of 0.5 could accelerate the anammox and denitrification activity,to reach as high as 84.9%±2.8% TN removal efficiency.Partial denitrification-anammox (PDN/anammox) and denitrification were proposed as the major pathways for nitrogen removal,accounting for 91.3% and 8.7% o...     

Evaluating CO2 reduction strategies in the US

We constructed a model to simulate emissions of CO₂ from electricity generation in the US and, using the model, we developed 20-year projections of emissions under various regulatory scenarios.     

The impacts of local farming system development trajectories on greenhouse gas emissions in the northern mountains of Vietnam

The northern mountain region of Vietnam (NMR) is dominated by swidden/fallow farming systems. The fallow land of these systems is populated by small trees and bushes. Since the 1960s the government of Vietnam has tried to limit or stop swiddening and replace it with permanent upland agricultural fields, paddy, fruit trees and animal husbandry. Discussion in the policy debate and literature focuses on the impacts these changes have on local people’s livelihoods. There have been no attempts to evaluate the impact of these changes on greenhouse gas (GHG) emissions. This paper examines the realities of current farming system changes taking place at the hamlet level and other changes that could take place due to government land use policies and extension programs. The paper answers the following questions: How could farming system changes influence net GHGs? Which farming system changes in the NMR, the trajectories of changes that are currently observed or those that would be followed if farmers adhere strictly to government policies and programs, will have a greater affect on the GHG contributions from agriculture in the region? Could ‘clean development mechanism’ (CDM) projects make a difference in the profitability of the pathways mentioned? Results show: (1) if farming systems in the NMR continue along currently observed change trajectories there will be increases in GHG emissions; (2) if the NMR farming systems change according to government policies and programs there will be a net sequestration of carbon in regrowing vegetation during the initial 20 years; (3) over the longer term, in areas where systems change to fit government policies, increased GHG emissions from other changes in the farming systems (e.g. increased paddy and increased pig raising in sties) will overtake the amounts of carbon sequestered in vegetation; (4) CMD projects only make a difference if (a) maximum biomass potential of regrowing fallow can be reached; (b) a favourable baseline is chosen; (c) timing and length of the accounting period is correct; and (d) farmers do not take compensatory action in response to government policies. Given these conditions it does not appear that currently envisioned clean development mechanisms would be beneficial to farmers in the NMR.     

西南岩溶区生态安全评价研究 ——以广西为例

西南岩溶区是举世公认的典型的生态环境脆弱系统之一,也是我国典型的极贫困代表区域之一.广西处于西南岩溶地区,岩溶面积为9.8×104km2,占广西土地总面积的41%.本文以广西为例,采用生态足迹的理论和方法来测算广西区域生态安全状况,对1990～2003年广西岩溶生态环境的生态足迹、生态承载力、生态盈亏及生态压力指数进行测算分析并提出预测模型.研究结果①广西生态足迹呈不断增加趋势,从1990年的0.601 7 hm2增加到2003年的1.137 8 hm2;②生态承载力呈不断下降趋势,从1990年的0.820 4 hm2减少到2003年的0.653 7 hm2;③生态盈亏从1990年生态盈余的0.218 8 hm2下降到2003年的生态赤字达-0.484 8 hm2,出现严重的生态赤字;④1990～2003年生态足迹压力指数由0.7334增加到1.7406,增长幅度巨大,从临界安全状态到不安全状态.     

Long-term dynamics of terrestrial carbon stocks in Austria: a comprehensive assessment of the time period from 1830 to 2000

This article presents a comprehensive data set on Austria’s terrestrial carbon stocks from the beginnings of industrialization in the year 1830 to the present. It is based on extensive historical and recent land use and forestry data derived from primary sources (cadastral surveys) for the early nineteenth century, official statistics available for later parts of the nineteenth century as well as the twentieth century, and forest inventory data covering the second half of the twentieth century. Total carbon stocks—i.e. aboveground and belowground standing crop and soil organic carbon—are calculated for the entire period and compared to those of potential vegetation. Results suggest that carbon stocks were roughly constant from 1830 to 1880 and have grown considerably from 1880 to 2000, implying that Austria’s vegetation has acted as a carbon sink since the late nineteenth century. Carbon stocks increased by 20% from approximately 1.0 GtC in 1830 and 1880 to approximately 1.2 GtC in the year 2000, a value still much lower than the amount of carbon terrestrial ecosystems are expected to contain in the absence of land use: According to calculations presented in this article, potential vegetation would contain some 2.0 GtC or 162% of the present terrestrial carbon stock, suggesting that the recent carbon sink results from a recovery of biota from intensive use in the past. These findings are in line with the forest transition hypothesis which claims that forest areas are growing in industrialized countries. Growth in forest area and rising carbon stocks per unit area of forests both contribute to the carbon sink. We discuss the hypothesis that the carbon sink is mainly caused by the shift from area-dependent energy sources (biomass) in agrarian societies to the largely area-independent energy system of industrial societies based above all on fossil fuels.     

黑碳监测在博物馆文物环境评价中的应用研究

每个博物馆所处地理环境、气候均有所不同,如何对博物馆展厅环境进行全面监测,最终对陈列展示的文物形成一套完整而有效的保护体系,是文物保护工作人员研究的主要课题。试验采用黑碳监测仪对上海中国航海博物馆展厅内部及馆外空气质量同步进行监测,根据采集到的数据分析,对馆内及周边黑碳的来源、浓度建立了一个初步的环境评价,同时,对博物馆今后文物保护工作所需注意事项也提出了相应的建议。     

乌海市炭素企业沥青烟气的监测分析与治理研究

本文通过对乌海市三家炭素企业排放烟气的监测（重点监测、苯并[a]芘）并进行数据分析。结合炭素生产工艺流程进行研究。提出了对沥青烟气治理所采取的相应措施。为做好乌海市炭素企业沥青烟气监测及改善沥青烟气污染状况提供了一定的参考依据。     

基于生态足迹法的建设项目生态承载力分析研究——以苏州东太湖滨湖新城为例

采用生态足迹模型,以苏州东太湖滨湖新城为例,分析《苏州东太湖滨湖新城规划》零规划期地区生态承载力的赤字盈余情况,是否在区域环境承载力允许范围内;规划实施后的生态承载力的进一步变化情况及原因。研究表明:(1)零规划期(2012年),苏州东太湖滨湖新城的生态需求是生态供给的63倍,已经远远超出地区生态承载力的范围;(2)未来《苏州东太湖滨湖新城规划》实施后,土地利用格局的改变,尤其是耕地的大面积减少,区域生态承载力降低了7 733.816 hm2。建议苏州东太湖滨湖新城开发尽量减少对生产力能力较高的土地占用,同时充分利用已有的天然屏障进行团块分割,同时也要对原有乡镇工业进行整治,通过功能置换实现资源节约利用和对乡镇经济的保护。