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1.
The Kyoto Protocol provides for the involvement of developing countries in an atmospheric greenhouse gas reduction regime under its Clean Development Mechanism (CDM). Carbon credits are gained from reforestation and afforestation activities in developing countries. Bangladesh, a densely populated tropical country in South Asia, has a huge degraded forestland which can be reforested by CDM projects. To realize the potential of the forestry sector in developing countries for full-scale emission mitigation, the carbon sequestration potential of different species in different types of plantations should be integrated with the carbon trading system under the CDM of the Kyoto Protocol. This paper discusses the prospects and problems of carbon trading in Bangladesh, in relation to the CDM, in the context of global warming and the potential associated consequences. The paper analyzes the effects of reforestation projects on carbon sequestration in Bangladesh, in general, and in the hilly Chittagong region, in particular, and concludes by demonstrating the carbon trading opportunities. Results showed that tree tissue in the forests of Bangladesh stored 92tons of carbon per hectare (tC/ha), on average. The results also revealed a gross stock of 190tC/ha in the plantations of 13 tree species, ranging in age from 6 to 23 years. The paper confirms the huge atmospheric CO(2) offset by the forests if the degraded forestlands are reforested by CDM projects, indicating the potential of Bangladesh to participate in carbon trading for both its economic and environmental benefit. Within the forestry sector itself, some constraints are identified; nevertheless, the results of the study can expedite policy decisions regarding Bangladesh's participation in carbon trading through the CDM.  相似文献   

2.
Large but feasible increases that have been projected for the production of wood energy in the United States can be expected to significantly alter the current carbon storage patterns in US forest vegetation. The 1976 net wood increment left after forest cutting equals about 136 × 106 tons of carbon/year, with about 60% of the increment found in merchantable trees, and the remainder in nonmerchantable components.Achieving 5–10 quads of wood energy beyond 1976 levels by the year 2010 can significantly change current carbon storage patterns with the magnitude of change dependent on the extent of residue harvest to meet energy goals, and the rate of future forest growth. Complete loss of the apparent net wood increment is a possible outcome.Although the future growth and harvest situation cannot be known now, a range of possible scenarios suggests that US forests in the year 2010 will store much less carbon than today, thus significantly changing their role in the global carbon cycle.  相似文献   

3.
Changes in forest and agricultural land management practices have the potential to increase carbon (C) storage by terrestrial systems, thus offsetting C emissions to the atmosphere from energy production. This study assesses that potential for three terrestrial management practices within the state of Virginia, USA: afforestation of marginal agricultural lands; afforestation of riparian agricultural lands; and changing tillage practices for row crops; each was evaluated on a statewide basis and for seven regions within the state. Lands eligible for each practice were identified, and the C storage potential of each practice on those lands was estimated through a modeling procedure that utilized land-resource characteristics represented in Geographic Information System databases. Marginal agricultural lands’ afforestation was found to have the greatest potential (1.4 Tg C yr−1, on average, over the first 20 years) if applied on all eligible lands, followed by riparian afforestation (0.2 Tg C yr−1 over 20 years) and tillage conversion (0.1 Tg C yr−1 over 14 years). The regions with the largest potentials are the Ridge and Valley of western Virginia (due to extensive areas of steep, shallow soils) and in the Mid-Atlantic Coastal Plain in eastern Virginia (wet soils). Although widespread and rapid implementation of the three modeled practices could be expected to offset only about 3.4% of Virginia’s energy-related CO2 emissions over the following 20 years (equivalent to about 8.5% of a Kyoto Treaty–based target), they could contribute to achievement of C-management goals if implemented along with other mitigation measures.  相似文献   

4.
The study deals with the problem of evaluating management strategies for pure stands of Norway spruce (Picea abies Karst) to balance adaptation to and mitigation of climate change, taking into account multiple objectives of a forest owner. A simulation and optimization approach was used to evaluate the management of a 1000 ha model Age-Class forest, representing the age-class distribution of an area of 66,000 ha of pure Norway spruce forests in the Black Forest region of Southwest Germany. Eight silvicultural scenarios comprising five forest conversion schemes which were interpreted as “adaptation” strategies which aims at increasing the proportion of Beech, that is expected to better cope with climate change than the existing Norway spruce, and three conventional strategies including a “Do-nothing” alternative classified as “mitigation”, trying to keep rather higher levels of growing stock of spruce, were simulated using the empirical growth simulator BWINPro-S. A linear programming approach was adapted to simultaneously maximize the net present values of carbon sequestration and timber production subject to the two constraints of wood even flow and partial protection of the oldest (nature protection). The optimized plan, with the global utility of 11,687 €/ha in forty years, allocated a combination of silvicultural scenarios to the entire forest area. Overall, strategies classified as “mitigation” were favored, while strategies falling into the “adaptation”-category were limited to the youngest age-classes in the optimal solution. Carbon sequestration of the “Do-nothing” alternative was between 1.72 and 1.85 million tons higher than the other alternatives for the entire forest area while the differences between the adaptation and mitigation approaches were approximately 133,000 tons. Sensitivity analysis showed that a carbon price of 21 €/t is the threshold at which carbon sequestration is promoted, while an interest rate of above 2% would decrease the amount of carbon.  相似文献   

5.
Afforestation of agricultural lands has been one of the major land use changes in China in recent decades. To better understand the effect of such land use change on soil quality, we investigated selected soil physical, chemical and microbial properties (0–15 cm depth) in marginal agricultural land and a chronosequence of poplar (Populus euramericana cv. ‘N3016’) plantations (5-, 10-, 15- and 20-years old) in a semi-arid area of Northeast China. Soil bulk density significantly declined after conversion of agricultural lands to poplar plantations. Soil total organic carbon (TOC) and nitrogen (TN) concentrations, microbial biomass C (MBC) and potential N mineralization rate (PNM) decreased initially following afforestation of agricultural lands, and then increased with stand development. However, soil metabolic quotient (qCO2) exhibited a reverse trend. In addition, soil particulate organic matter C (POM-C) and N (POM-N) concentrations showed no significant changes in the first 10 years following afforestation, and then increased with stand age. These findings demonstrated that soil quality declined initially following afforestation of agricultural lands in semi-arid regions, and then recovered with stand development. Following 15 years of afforestation, many soil quality parameters recovered to the values found in agricultural land. We propose that change in soil quality with stand age should be considered in determining optimum rotation length of plantations and best management practices for afforestation programs.  相似文献   

6.
This study explores the economic attractiveness of afforestation as a strategy for the joint production of fibre, carbon storage and biosolids (treated municipal sewage sludge) disposal for municipalities in Southern and Central Ontario, Canada. We use a spatial, stochastic model, the Canadian Forest Service Afforestation Feasibility Model (CFS-AFM), to simulate a range of spatial biosolids application scenarios in hybrid poplar afforestation projects. Results suggest that such joint afforestation strategies could be financially attractive. Significant cost savings can be expected through decreases in transportation distances and avoided waste disposal fees. Sensitivity analysis is used to examine the effects of variations in critical model parameters on net present values. Our findings indicate that waste disposal savings from application of biosolids on hybrid poplar plantations combined with incentives for landowners to sequester carbon can easily compete with agricultural land rental values in some regions of Ontario. Social acceptance of this kind of activity, however, may be an impediment to adoption.  相似文献   

7.
The United States Climate Change Initiative includes improvements to the U.S. Department of Energy's Voluntary Greenhouse Gas Reporting Program. The program includes specific accounting rules and guidelines for reporting and registering forestry activities that reduce atmospheric CO2 by increasing carbon sequestration or reducing emissions. In the forestry sector, there is potential for the economic value of emissions credits to provide increased income for landowners, to support rural development, to facilitate the practice of sustainable forest management, and to support restoration of ecosystems. Forestry activities with potential for achieving substantial reductions include, but are not limited to: afforestation, mine land reclamation, forest restoration, agroforestry, forest management, short-rotation biomass energy plantations, forest protection, wood production, and urban forestry. To be eligible for registration, the reported reductions must use methods and meet standards contained in the guidelines. Forestry presents some unique challenges and opportunities because of the diversity of activities, the variety of practices that can affect greenhouse gases, year-to-year variability in emissions and sequestration, the effects of activities on different forest carbon pools, and accounting for the effects of natural disturbance.  相似文献   

8.
Climate change involves increasing atmospheric carbon dioxide concentration which is driven by anthropogenic emissions. Afforestation, which is the establishment of forests on previously non‐forested lands, could be a suitable climate change mitigation strategy. The aim of this research is to evaluate the carbon sequestration capability of the Eucalyptus and Prosopis species in the Reza‐Abad afforestation park in western Iran. For this aim, three stands of any species were selected. For quantitative assessment, a transect was implemented at the length of 100 m. In trees located of transects, the general characteristics of species were measured. Also, for estimating the amount of litter, a sample plot has been measured at the center of the quadrate. These samples were taken from the afforested area, the control area inside the afforested area and another control area outside. In each stand, species were selected randomly and one‐eighth of the whole stand was taken for calculating the percentage of carbon and aerial biomass. Then the aboveground organs were weighted and after the transfer of different plant organs to the laboratory, the conversion factor of carbon sequestration of the plant organs was determined individually by combustion method. Also, soil samples were also collected from two depths of 0–15 and 15–30 cm in each of the cultivated and control parts. The results showed that there is a significant difference between the species and Prosopis has higher carbon sequestration than Eucalyptus. The carbon sequestration among different organs showed a significant difference, carbon sequestration was 19.24 t/ha for Eucalyptus and 18.43 t/ha for Prosopis. After an economic calculation, it was concluded that afforestation has a positive effect on the reduction of atmospheric carbon dioxide. Hence, these results allow decision makers to change land use from desert area to forest, and planting the Prosopis species is more recommendable than Eucalyptus for afforestation in such areas which are economically profitable.  相似文献   

9.
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   

10.
To test the effectiveness of the 404 permit program in preventing a net loss of wetland resources, 75 Section 404 projects permitted in the years 1987–1989 and located in a portion of southern California were evaluated. From this group of projects, 80.47 ha of wetlands were affected by Section 404 permits and the Army Corps of Engineers required 111.62 ha of wetland mitigation. To verify the successful completion of each mitigation project, all 75 project sites were visited and evaluated based on the amount of dead vegetation, growth and coverage, and the number of invasive species. Based on the field verification results, the actual amount of completed mitigation area was 77.33 ha, resulting in a net loss of 3.14 ha of wetland resources in the years 1987–1989. By comparing the types of wetlands lost to the types of wetlands mitigated, it is apparent that, in particular, freshwater wetlands are experiencing a disproportionately greater loss of area and that riparian woodland wetlands are most often used in mitigation efforts. The net result of these accumulated actions is an overall substitution of wetland types throughout the region. Results also indicate that, typically, large-scale mitigation projects are more successful compared to smaller projects and that successful compliance efforts are not evenly distributed throughout the region. We recommend that better monitoring, mitigation in-kind, mitigation banking, and planning on a regional or watershed scale could greatly improve the effectiveness of the Section 404 permitting program.  相似文献   

11.
A carbon budget was calculated for Tompkins County, NY, a semi-rural upstate county with a population density of 78 pp/km2. The costs and potential for several carbon mitigation options were analyzed in four categories: terrestrial C sequestration, local power generation, transportation, and energy end-use efficiency. This study outlines a methodology for conducting this type of local-scale analysis, including sources and calculations adaptable to different localities. Effective carbon mitigation strategies for this county based on costs/Mg C and maximum potential include reforestation of abandoned agricultural lands, biomass production for residential heating and co-firing in coal power plants, changes in personal behavior related to transportation (e.g., public transportation), installation of residential energy efficient products such as programmable thermostats or compact fluorescent light bulbs, and development of local wind power. The total county emissions are about 340 Gg C/year, with biomass sequestration rates of 121 Gg C/year. The potential for mitigation, assuming full market penetration, amounts to about 234 Gg C/year (69%), with 100 Gg C/year (29%) at no net cost to the consumer. The development of local-scale C mitigation plans based on this sort of model of analysis is feasible and would be useful for guiding investments in climate change prevention.  相似文献   

12.

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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13.
Biomass production and carbon storage in short-rotation poplar plantations over 10 years were evaluated at the Hanyuan Forestry Farm, Baoying County, China. Experimental treatments applied in a split-plot design included four planting densities (1111, 833, 625 and 500 stems ha(-1)) and three poplar clones (NL-80351, I-69 and I-72). Based on the model of total biomass production developed, total plantation biomass production was significantly different in the plantations. The ranking of the plantation biomass production by planting density was 1111>833 more more than 625>500 stems ha(-1), and by components was stem>root>or=branch>leaf for all plantations. At 10 years, the highest total biomass in the plantation of 1111 stems ha(-1) reached about 146 t ha(-1), which was 5.3%, 11.6% and 24.2% higher than the plantations of 833, 625 and 500 stems ha(-1), respectively. The annual increment of biomass production over 10 years differed significantly among initial planting densities and stand ages (p<0.01), but no significant difference was observed from age 7 to 10. Mean carbon concentration among all biomass components ranged from 42-50%, with the highest carbon concentrations in stems and the lowest in leaves. Over the study period, the dynamic pattern of total plantation carbon storage by planting density was similar to that of total biomass production. At age 10, the highest total plantation carbon storage in the plantation of 1111 stems ha(-1) reached about 72.0 t ha(-1), which was 5.4%, 11.9% and 24.8% higher than in the plantations of 833, 625 and 500 stems ha(-1), respectively. The annual carbon storage increment over 10 years differed significantly among initial planting densities and stand ages (p<0.01), and it showed a pattern similar to the annual biomass production increment of the plantations. The results suggest that biomass production and carbon storage potential were highest for planting densities of 1111 and 833 stems ha(-1) grown over 5- and 6-year cutting cycles, respectively. If 3- or 4-year cutting cycles are used, the planting density should be higher than 1111 stems ha(-1) (e.g., 1667 or 2500 stems ha(-1)). Based on the mean annual carbon storage for the plantation of 625 stems ha(-1), as an estimation, the mean carbon storage in the biomass of poplar plantations (excluding leaves) amounts to 3.75x10(7) t ha(-1)yr(-1) in China.  相似文献   

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Coastal wetlands are dynamic ecosystems subject to the manipulative powers of both humans and sea. Areal changes in the tidal wetlands of Delaware were monitored over a six year period with color and color infrared aerial photography. Wetland changes were interpreted directly from the photography and were classified according to natural and legal categories of change. Human activities in tidal wetlands destroyed an average 8.1 ha of wetlands annually from 1973 to 1979. During the same period 3.9 ha of wetlands were eroded and 2.8 ha of wetlands were formed annually by natural processes. A total net loss of 55.1 ha of wetlands was estimated for the six year period. The enactment of state and federal legislation protecting wetlands in 1972–1973 resulted in a decrease of wetlands loss in Delaware from an average of 179.7 ha yr?1 from 1954 to 1971 to the 8.1 ha yr?1 determined by this study. The dynamic nature of these wetlands exemplifies the need for frequent monitoring and remapping, if an effective and accurate management program is to remain in operation  相似文献   

16.
One of the largest changes in US forest type areas over the last half-century has involved pine types in the South. The area of planted pine has increased more than 10-fold since 1950, mostly on private lands. Private landowners have responded to market incentives and government programs, including subsidized afforestation on marginal agricultural land. Timber harvest is a crucial disturbance affecting planted pine area, as other forest types are converted to planted pine after harvest. Conversely, however, many harvested pine plantations revert to other forest types, mainly due to passive regeneration behavior on nonindustrial private timberlands. We model land use and land cover changes as a basis for projecting future changes in planted pine area, to aid policy analysts concerned with mitigation activities for global climate change. Projections are prepared in two stages. Projected land use changes include deforestation due to pressures to develop rural land as the human population expands, which is a larger area than that converted from other rural lands (e.g., agriculture) to forestry. In the second stage, transitions among forest types are projected on land allocated to forestry. We consider reforestation, influences of timber harvest, and natural succession and disturbance processes. Baseline projections indicate a net increase of about 5.6 million ha in planted pine area in the South over the next 50 years, with a notable increase in sequestered carbon. Additional opportunities to expand pine plantation area warrant study of landowner behavior to aid in designing more effective incentives for inducing land use and land cover changes to help mitigate climate change and attain other goals.  相似文献   

17.
Pine plantations are an alternative to marginal agriculture in many countries, and are often presented as an option that improves biodiversity. However, these plantations can have adverse environmental effects if improperly managed. To evaluate the effect of forest management practices on biodiversity, the diversity, species richness, dominance and frequency of understory woody plant species in different forests of the Basque Country (northern Spain) were compared. Plantations of exotic conifers (Pinus radiata [D.] Don) of different ages were compared with deciduous forests of Quercus robur L. and Fagus sylvatica L. The effects of different types and intensities of management were taken into account. The differences observed were mainly conditioned by the intensity of forestry management, although the response varied according to forest type and age. In unmanaged pine plantations, the diversity and species richness of the understory increased rapidly after planting (while dominance decreased), remained stable in the intermediate age range, and reached a maximum in plantations more than 25 years of age. Management practices resulted in decreased understory diversity and species richness, as well as greater dominance. This was more pronounced in younger than in older stands. Moderate management, however, favored a greater diversity of the understory in deciduous forests. The species composition of the plantations and deciduous forests were different, the latter having a wider range of characteristic species. Knowledge of how forestry practices influence biodiversity (in terms of diversity, richness, dominance, and species composition) may allow predictions to be made about the diversity achievable with different management systems.  相似文献   

18.
Tropical deforestation is a significant contributor to accumulation of greenhouse gases (GHGs) in the atmosphere. GHG emissions from deforestation in the tropics were in the range of 1 to 2 Pg C yr(-1) for the 1990s, which is equivalent to as much as 25% of global anthropogenic GHG emissions. While there is growing interest in providing incentives to avoid deforestation and consequently reduce net carbon emissions, there is limited information available on the potential costs of these activities. This paper uses a global forestry and land use model to analyze the potential marginal costs of reducing net carbon emissions by avoiding deforestation in tropical countries. Our estimates suggest that about 0.1 Pg C yr(-1) of emissions reductions could be obtained over the next 30 to 50 yr for $5 per Mg C, and about 1.6 Pg C yr(-1) could be obtained over the same time frame for $100 per Mg C. In addition, the effects of carbon incentives on land use could be substantial. Relative to projected baseline conditions, we find that there would be around 3 million additional hectares (ha) of forestland in 2055 at $5 per Mg C and 422 million ha at $100 per Mg C. Estimates of reductions in area deforested, GHG mitigation potential, and annual land rental payments required are presented, all of which vary by region, carbon price paid, and time frame of mitigation.  相似文献   

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