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Greenhouse gas (GHG) mitigation options in the Russian forest sector include: afforestation and reforestation of unforested/degraded land area; enhanced forest productivity; incorporation of nondestructive methods of wood harvesting in the forest industry; establishment of land protective forest stands; increase in stand age of final harvest in the European part of Russia; increased fire control; increased disease and pest control; and preservation of old growth forests in the Russian Far-East, which are presently threatened. Considering the implementation of all of the options presented, the GHG mitigation potential within the forest and agroforestry sectors of Russia is approximately 0.6–0.7 Pg C/yr or one half of the industrial carbon emissions of the United States. The difference between the GHG mitigation potential and the actual level of GHGs mitigated in the Russian forest sector will depend to a great degree on external financing that may be available. One possibility for external financing is through joint implementation (JI). However, under the JI process, each project will be evaluated by considering a number of criteria including also the difference between the carbon emissions or sequestration for the baseline (or reference) and the project case, the permanence of the project, and leakage. Consequently, a project level assessment must appreciate the near-term constraints that will face practitioners who attempt to realize the GHG mitigation potential in the forest and agroforestry sectors of their countries.

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3.
Forests and soils are a major sink of carbon, and land use changes can affect the magnitude of above ground and below ground carbon stores and the net flux of carbon between the land and the atmosphere. Studies on methods for examining the future consequences of changes in patterns of land use change and carbon flux gains importance, as they provide different options for CO2 mitigation strategies. In this study, a simulation approach combining Markov chain processes and carbon pools for forests and soils has been implemented to study the carbon flows over a period of time. Markov chains have been computed by converting the land use change and forestry data of India from 1997 to 1999 into a matrix of conditional probabilities reflecting the changes from one class at time t to another class time t+1. Results from Markov modeling suggested Indian forests as a potential sink for 0.94 Gt carbon, with an increase in dense forest area of about 75.93 Mha and decrease of about 3.4 Mha and 5.0 Mha in open and scrub forests, if similar land use changes that occurred during 1997–1999 would continue. The limiting probabilities suggested 34.27 percent as dense forest, 6.90 as open forest, 0.4 percent mangrove forest, 0.1 percent scrub and 58 percent as non-forest area. Although Indian forests are found to be a potential carbon sink, analysis of results from transition probabilities for different years till 2050 suggests that, the forests will continue to be a source of about 20.59 MtC to the atmosphere. The implications of these results in the context of increasing anthropogenic pressure on open and scrub forests and their contribution to carbon source from land use change and forestry sector are discussed. Some of the mitigation aspects to reduce greenhouse gas emissions from land use change and forestry sector in India are also reviewed in the study.  相似文献   

4.
Greenhouse gas (GHG) mitigation options in the Russian forest sector include: afforestation and reforestation of unforested/degraded land area; enhanced forest productivity; incorporation of nondestructive methods of wood harvesting in the forest industry; establishment of land protective forest stands; increase in stand age of final harvest in the European part of Russia; increased fire control; increased disease and pest control; and preservation of old growth forests in the Russian Far-East, which are presently threatened. Considering the implementation of all of the options presented, the GHG mitigation potential within the forest and agroforestry sectors of Russia is approximately 0.6–0.7 Pg C/yr or one half of the industrial carbon emissions of the United States. The difference between the GHG mitigation potential and the actual level of GHGs mitigated in the Russian forest sector will depend to a great degree on external financing that may be available. One possibility for external financing is through joint implementation (JI). However, under the JI process, each project will be evaluated by considering a number of criteria including also the difference between the carbon emissions or sequestration for the baseline (or reference) and the project case, the permanence of the project, and leakage. Consequently, a project level assessment must appreciate the near-term constraints that will face practitioners who attempt to realize the GHG mitigation potential in the forest and agroforestry sectors of their countries.  相似文献   

5.
Carbon flows and carbon use in the German anthroposphere: An inventory   总被引:2,自引:0,他引:2  
Today, global climate change is one of the most urgent environmental problems. The atmospheric concentration of carbon dioxide (CO2) has to be stabilised by significant reductions of CO2 emissions in the next decades to keep the expected temperature rise within tolerable borders. Efforts exceeding the implemented measures to reduce CO2 emissions in Germany are desirable. An important pre-condition for such measures is a scientific-based inventory of the sources, sinks, and use of carbon.In this paper, we present CarboMoG, i.e. Carbon Flow Model of Germany. CarboMoG is a carbon flow model covering carbon flows, carbon sources and sinks in Germany and the German anthroposphere, showing concurrent energy and non-energy use of carbon sources.The model consists of seven modules in German anthroposphere following the German classification of economic sectors. Carbon flows to and from atmosphere and lithosphere as well as imports and exports were included into the model. The model comprises roughly 220 material flows determined based on material flow procedures for the base year 2000.Main sources of carbon are fossil energy carriers from lithosphere and uptake of CO2 by crops (52% resp. 48% of all carbon sources). The model calculations show that import of energy carriers dominates total carbon import to Germany (82%). Total non-energy use of carbon in Germany is significantly higher than energy use (386 Mt C and 230 Mt C, resp.). Carbon throughput of Industry is greatest (about 224 Mt C input), followed by Energy (about 129 Mt C input). Agriculture and Forestry & Industry show the highest figure for non-energy use of carbon, energy use of carbon is largest in the Energy sector. Emissions of CO2 to atmosphere account for 94% of all carbon flows to sinks in Germany. Carbon accumulates in German anthroposphere 5 Mt C in 2000.  相似文献   

6.

As part of the studies related to the obligations of the UN Framework Convention on Climate Change, the Republic of Kazakhstan started activities to inventory greenhouse gas (GHG) emissions and assess of GHG mitigation options. The objective of this paper is to present an estimate of the possibility of mitigating GHG emissions and determine the mitigation priorities. It presents a compilation of the possible options and their assessment in terms of major criteria and implementation feasibility. Taking into account the structure of GHG emissions in Kazakhstan in 1990, preliminary estimates of the potential for mitigation are presented for eight options for the energy sector and agriculture and forestry sector. The reference scenario prepared by expert assessments assumes a reduction of CO2 emissions in 1996–1998 by about 26% from the 1990 level due to general economic decline, but then emissions increase. It is estimated that the total potential for the mitigation of CO2 emissions for the year 2000 is 3% of the CO2 emissions in the reference scenario. The annual reduction in methane emissions due to the estimated options can amount to 5%–6% of the 1990 level.

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7.
ABSTRACT: There are increasing concerns in the forestry community about global climate change and variability associated with elevated atmospheric CO2. Changes in precipitation and increases in air temperature could impose additional stress on forests during the next century. For a study site in Carteret County, North Carolina, the General Circulation Model, HADCM2, predicts that by the year 2099, maximum air temperature will increase 1.6 to 1.9°C, minimum temperature will increase 2.5 to 2.8°C, and precipitation will increase 0 to 10 percent compared to the mid‐1990s. These changes vary from season to season. We utilized a forest ecosystem process model, PnET‐II, for studying the potential effects of climate change on drainage outflow, evapotranspiration, leaf area index (LAI) and forest Net Primary Productivity (NPP). This model was first validated with long term drainage and LAI data collected at a 25‐ha mature loblolly pine (Pinus taeda L.) experimental watershed located in the North Carolina lower coastal plain. The site is flat with poorly drained soils and high groundwater table. Therefore, a high field capacity of 20 cm was used in the simulation to account for the topographic effects. This modeling study suggested that future climate change would cause a significant increase of drainage (6 percent) and forest productivity (2.5 percent). Future studies should consider the biological feedback (i.e., stomata conductance and water use efficiency) to air temperature change.  相似文献   

8.
Tropical deforestation provides a significant contribution to anthropogenic increases in atmospheric CO2 concentration that may lead to global warming. Forestation and other forest management options to sequester CO2 in the tropical latitudes may fail unless they address local economic, social, environmental, and political needs of people in the developing world. Forest management is discussed in terms of three objectives: carbon sequestration, sustainable development, and biodiversity conservation. An integrated forest management strategy of land-use planning is proposed to achieve these objectives and is centered around: preservation of primary forest, intensified use of nontimber resources, agroforestry, and selective use of plantation forestry. The information in this document has been wholly funded by the US Environmental Protection Agency. It has been subjected to the agency's peer and administrative review and approved for publication of an EPA document. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.  相似文献   

9.
This paper introduces an integrated assessment (IA) approach for a Canada-China joint research project that linked forest carbon sequestration, forest resource management, and local sustainability enhancement. The purpose of the IA was to improve the measurement of carbon in different land uses and vegetation covers, as well as to direct decision makers to those land uses or options as an CO2 emission reduction strategy while supporting rural sustainable development. In this connection, three questions are addressed in this paper:
1)
How will forestry carbon sequestration land use policies affect regional sustainability prospects in rural China?  相似文献   

10.
ABSTRACT: Large deviations in average annual air temperatures and total annual precipitation were observed across the southern United States during the last 50 years, and these fluctuations could become even larger during the next century. We used PnET-IIS, a monthly time-step forest process model that uses soil, vegetation, and climate inputs to assess the influence of changing climate on southern U.S. pine forest water use. After model predictions of historic drainage were validated, the potential influences of climate change on loblolly pine forest water use was assessed across the region using historic (1951 to 1984) monthly precipitation and air temperature which were modified by two general circulation models (GCMs). The GCMs predicted a 3.2°C to 7.2°C increase in average monthly air temperature, a -24 percent to + 31 percent change in monthly precipitation and a -1 percent to + 3 percent change in annual precipitation. As a comparison to the GCMs, a minimum climate change scenario using a constant 2°C increase in monthly air temperature and a 20 percent increase in monthly precipitation was run in conjunction with historic climate data. Predicted changes in forest water drainage were highly dependent on the GCM used. PnET-IIS predicted that along the northern range of loblolly pine, water yield would decrease with increasing leaf area, total evapotranspiration and soil water stress. However, across most of the southern U.S., PnET-IIS predicted decreased leaf area, total evapotranspiration, and soil water stress with an associated increase in water yield. Depending on the GCM and geographic location, predicted leaf area decreased to a point which would no longer sustain loblolly pine forests, and thus indicated a decrease in the southern most range of the species within the region. These results should be evaluated in relation to other changing environmental factors (i.e., CO2 and O3) which are not present in the current model.  相似文献   

11.
The effect of impregnation of activated carbon with Cr2O and Fe2O3 and promotion by Zn2+ on its adsorptive properties of carbon dioxide was studied using a volumetric adsorption apparatus at ambient temperature and low pressures. Slurry and solution impregnation methods were used to compare CO2 capture capacity of the impregnated activated carbon promoted by Zinc. The obtained adsorption isotherms showed that amount of CO2 adsorbed on the samples impregnated by Cr2O was increased about 20% in compare to raw activated carbon. The results also showed that Fe2O3 was not an effective impregnating species for activated carbon modification. Moreover slurry impregnation method showed higher CO2 adsorption capacity in comparison with solution impregnation method. Samples prepared by co-impregnation of two metal species showed more adsorption capacity than samples impregnated by just one metal species individually. Washing the impregnated samples by metal oxide resulted in 15% increase in CO2 adsorption capacities of activated carbons which can be attributed to the metal oxides removal covering the adsorption surface. Decreasing impregnation temperature from 95 to 25 °C in solution method showed a significant increase in CO2 adsorption capacity. Sips equation was found a suitable model fitting to the adsorption data in the range studied.  相似文献   

12.
Due to its compatibility with the current energy infrastructures and the potential to reduce CO2 emissions significantly, CO2 capture and geological storage is recognised as one of the main options in the portfolio of greenhouse gas mitigation technologies being developed worldwide. The CO2 capture technologies offer a number of alternatives, which involve different energy consumption rates and subsequent environmental impacts. While the main objective of this technology is to minimise the atmospheric greenhouse gas emissions, it is also important to ensure that CO2 capture and storage does not aggravate other environmental concerns. This requires a holistic and system-wide environmental assessment rather than focusing on the greenhouse gases only. Life Cycle Assessment meets this criteria as it not only tracks energy and non-energy-related greenhouse gas releases but also tracks various other environmental releases, such as solid wastes, toxic substances and common air pollutants, as well as the consumption of other resources, such as water, minerals and land use. This paper presents the principles of the CO2 capture and storage LCA model developed at Imperial College and uses the pulverised coal post-combustion capture example to demonstrate the methodology in detail. At first, the LCA models developed for the coal combustion system and the chemical absorption CO2 capture system are presented together with examples of relevant model applications. Next, the two models are applied to a plant with post-combustion CO2 capture, in order to compare the life cycle environmental performance of systems with and without CO2 capture. The LCA results for the alternative post-combustion CO2 capture methods (including MEA, K+/PZ, and KS-1) have shown that, compared to plants without capture, the alternative CO2 capture methods can achieve approximately 80% reduction in global warming potential without a significant increase in other life cycle impact categories. The results have also shown that, of all the solvent options modelled, KS-1 performed the best in most impact categories.  相似文献   

13.
This study presents a comparison of different concepts for delivering combined heat and power (CHP) to a refinery in Norway. A reference case of producing high pressure steam from natural gas in boilers and electricity in a combined cycle power plant, is compared to a: (1) natural gas fueled CHP without any CO2 capture; (2) hydrogen fueled CHP with hydrogen produced from steam methane reforming (SMR); (3) hydrogen fueled CHP with hydrogen produced from autothermal reforming (ATR); and finally (4) natural gas fueled CHP with postcombustion CO2 removal. The options are compared on the basis of first law efficiency, emissions of CO2 and a simplified cash flow evaluation. Results show that in terms of efficiency the standard natural gas fueled CHP performs better than the reference case as well as the options with carbon capture. The low carbon options in turn offer lower emissions of greenhouse gases while maintaining the same efficiency as the reference case. The cash flow analysis shows that for any option, a certain mix of prices is required to produce a positive cash flow. As expected, the relationship between natural gas price and electricity price affects all options. Also the value of heat and CO2 emissions plays an important role.  相似文献   

14.
Overview of Contemporary Issues of Forest Research and Management in China   总被引:1,自引:0,他引:1  
With 207 million ha of forest covering 22% of its land area, China ranks fifth in the world in forest area. Rapid economic growth, climate change, and forest disturbances pose new, complex challenges for forest research and management. Progress in meeting these challenges is relevant beyond China, because China’s forests represent 34% of Asia’s forests and 5% of the worlds’ forests. To provide a broader understanding of these management challenges and of research and policies that address them, we organized this special issue on contemporary forest research and management issues in China. At the national level, papers review major forest types and the evolution of sustainable forestry, the development of China’s forest-certification efforts, the establishment of a forest inventory system, and achievements and challenges in insect pest control in China. Papers focused on Northern China address historical, social, and political factors that have shaped the region’s forests; the use of forest landscape models to assess how forest management can achieve multiple objectives; and analysis and modeling of fuels and fire behavior. Papers addressing Central and South China describe the “Grain for Green” program, which converts low productivity cropland to grassland and woodland to address erosion and soil carbon sequestration; the potential effects of climate change on CO2 efflux and soil respiration; and relationships between climate and net primary productivity. China shares many forest management and research issues with other countries, but in other cases China’s capacity to respond to forest management challenges is unique and bears watching by the rest of the world.  相似文献   

15.
Carbon sinks and sources in China's forests during 1901-2001   总被引:1,自引:0,他引:1  
This paper reports the annual carbon (C) balance of China's forests during 1901-2001 estimated using the Integrated Terrestrial Ecosystem C-budget model (InTEC). Annual carbon source and sink distributions are simulated for the same period using various spatial datasets including land cover and leaf area index (LAI) obtained from remote sensing, soil texture, climate, forest age, and nitrogen deposition. During 1901-1949, China's forests were a source of 21.0+/-7.8 Tg C yr(-1) due to disturbances (human activities). Its size increased to 122.3+/-25.3 Tg C yr(-1) during 1950-1987 due to intensified human activities in the late 1950s, early 1960s, 1970s and early 1980s. The forests became large sinks of 176.7+/-44.8 Tg C yr(-1) during 1988-2001, owing to large-scale plantation and forest regrowth in previously disturbed areas as well as growth stimulation by nondisturbance factors such as climatic warming, atmospheric CO(2) fertilization, and N deposition. From 1901 to 2001, China's forests were a small carbon source of 3.32 Pg C, about 32.9+/-22.3 Tg C yr(-1). The overall C balance in biomass from InTEC generally agrees with previous results derived from forest inventories of China's forests. InTEC results also include C stock variation in soils and are therefore more comprehensive than previous results. The uncertainty in InTEC results is still large, but it can be reduced if a detailed forest age map becomes available.  相似文献   

16.
Stable carbon isotopes are important tools to assess potential storage sites for CO2, as they allow the quantification of ionic trapping via isotope mass balances. In deep geological formations high p/T conditions need to be considered, because CO2 dissolution, equilibrium constants and isotope fractionation of dissolved inorganic carbon (DIC) depend on temperature, pressure and solute composition. After reviewing different approaches to account for these dependencies, an expanded scheme is presented for speciation and carbon isotope fractionation of DIC and dissolution of CaCO3 for pCO2 up to 100 bar, pH down to 3 and temperatures of up to 200 °C. The scheme evaluates the influence of respective parameters on isotope ratios during CO2 sequestration. The pCO2 and pH are the dominant controlling factors in the DIC/δ13C/pH system. The fugacity of CO2 has major impact on DIC concentrations at temperatures below 100 °C at high pCO2. Temperature dependency of activities and equilibrium dominates at temperatures above 100 °C. Isotope ratios of DIC are expected to be about 1–2‰ more depleted in 13C compared to the free CO2 at pCO2 values above 10 bar. This depletion is controlled by carbon isotope fractionation between CO2 and H2CO3* which is the dominant species of DIC at the resulting pH below 5.  相似文献   

17.
A possible response to increasing atmospheric CO2 concentration is to attempt to increase the amount of carbon stored in terrestrial vegetation. One approach to increasing the size of the terrestrial carbon sink is to increase the growth of forests by utilizing intensive forest management practices. This article uses data from the literature and from forest growth and yield models to analyze the impact of three management practices on carbon storage: thinning, fertilization, and control of competing vegetation. Using Douglas-fir (Pseudotsuga menziesii) and loblolly pine (Pinus taeda) as example species, results from experiments with computer simulation models suggest that, for these two species, thinning generally does not increase carbon storage and may actually cause a decrease. The exception is thinning of very dense young stands. Fertilization generally increases carbon storage, although the response can be quite variable. The largest gains in carbon storage are likely to come from fertilizing lower-quality sites and from fertilizing thinned or less dense stands. Forests usually show increased growth in response to fertilization over a wide range of ages. Simulation of the growth of loblolly pine indicates that controlling competing vegetation at an early age helps to maximize stand growth and carbon storage. The research described in this article has been funded by the US Environmental Protection Agency. This document has been prepared at the EPA Environmental Research Laboratory in Corvallis, Oregon, through contract number 68-C8-0006 to NSI Technology Inc. It has been subjected to the agency’s peer and administrative review and approved for publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.  相似文献   

18.
The current anthropogenic activities and climate change are increasingly becoming a growing global concern for dry tropical forests. Worldwide, these ecologically important forests have degraded considerably since the past few decades due to such factors. These factors have harmful consequences on the vegetation structure and diversity especially tree seedlings, which may further aggravate climate change. Generally, the vegetation recovery is very slow and unpredictable in the dry tropics due to complex interaction among tree seedling, site (particularly, soil) and climatic conditions. We inculcated that a better understanding of the behavior of individuals of different tree species at seedling stage in dry forests is of immense importance. It is increasingly being recognized for explaining and managing the future composition of plant communities under changing environmental conditions. In this regard, the multi-factorial interaction studies under various resource–disturbance combinations are needed in dry tropical ecosystems to understand the: (1) impact of relative variability in resources and disturbances on the responses of tree seedlings of native species and (2) how the later relates to distinct functional and life history traits of the individual tree species. Most importantly, such studies would improve our limited understanding of how variation (natural and man-made) in nutrient availability, under the influence of other local environmental factors (such as water, light, grass competition, herbivory, fire, allelopathy and enhanced CO2 conditions), would affect the dynamics of dry tropical forest community. It may help in the proper management of these forests. Moreover, it may prove helpful in the current climate change scenario, as change in forest community dynamics may have consequences on soil C sequestration and CO2 efflux at global scale.  相似文献   

19.

The models used to assess greenhouse gas mitigation options for the Czech Republic are discussed and compared with respect to their capabilities and ease of use. The input data and preliminary results are described. According to the projections, Czech CO2 emissions will not exceed their 1990 level until 2010. Assessment of several mitigation options shows that a 6% reduction in CO2 emissions can be achieved using cost-effective technologies. Key areas for mitigation measures are fuel switching from brown coal to natural gas through replacement of boilers, efficiency improvements in household heating, and use of compact fluorescent lamps.

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20.
Ecosystems in the western Mediterranean basin have undergone intense changes in land use throughout the centuries, resulting in areas with severe alterations. Today, most these areas have become sensitive to human activity, prone to profound changes in land-use configuration and ecosystem services. A consensus exists amongst stakeholders that ecosystem services must be preserved but managerial strategies that help to preserve them while ensuring sustainability are often inadequate. To provide a basis for measuring implications of land-use change on carbon sequestration services, changes in land use and associated carbon sequestration potential throughout the 20th century in a rural area at the foothills of the Sierra Nevada range (SE Spain) were explored. We found that forest systems replaced dryland farming and pastures from the middle of the century onwards as a result of agricultural abandonment and afforestation programs. The area has always acted as a carbon sink with sequestration rates ranging from 28,961 t CO2 year?1 in 1921 to 60,635 t CO2 year?1 in 1995, mirroring changes in land use. Conversion from pastures to woodland, for example, accounted for an increase in carbon sequestration above 30,000 t CO2 year?1 by the end of the century. However, intensive deforestation would imply a decrease of approximately 66% of the bulk CO2 fixed. In our study area, woodland conservation is essential to maintain the ecosystem services that underlie carbon sequestration. Our essay could inspire policymakers to better achieve goals of increasing carbon sequestration rates and sustainability within protected areas.  相似文献   

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