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1.
Climate change is projected to impact forest ecosystems, including biodiversity and Net Primary Productivity (NPP). National level carbon forest sector mitigation potential estimates are available for India; however impacts of projected climate change are not included in the mitigation potential estimates. Change in NPP (in gC/m2/yr) is taken to represent the impacts of climate change. Long term impacts of climate change (2085) on the NPP of Indian forests are available; however no such regional estimates are available for short and medium terms. The present study based on GCM climatology scenarios projects the short, medium and long term impacts of climate change on forest ecosystems especially on NPP using BIOME4 vegetation model. We estimate that under A2 scenario by the year 2030 the NPP changes by (−5) to 40% across different agro-ecological zones (AEZ). By 2050 it increases by 15% to 59% and by 2070 it increases by 34 to 84%. However, under B2 scenario it increases only by 3 to 25%, 3.5 to 34% and (−2.5) to 38% respectively, in the same time periods. The cumulative mitigation potential is estimated to increase by up to 21% (by nearly 1 GtC) under A2 scenario between the years 2008 and 2108, whereas, under B2 the mitigation potential increases only by 14% (646 MtC). However, cumulative mitigation potential estimates obtained from IBIS—a dynamic global vegetation model suggest much smaller gains, where mitigation potential increases by only 6% and 5% during the period 2008 to 2108.  相似文献   

2.
Short rotation bioenergy crops for energy production are considered an effective means to mitigate the greenhouse effect, mainly due to their ability to substitute fossil fuels. Alternatively, carbon can be sequestered and stored in the living biomass. This paper compares the two land use categories (forest land and non-forest land) for two management practices (short rotation vs. long rotation) to study mitigation potential of afforestation and fossil fuel substitution as compared to carbon storage. Significant carbon benefit can be obtained in the long run from using lands for growing short rotation energy crops and substituting fossil fuels by the biomass thus produced, as opposed to sequestering carbon in the biomass of the trees. When growth rates are high and harvest is used in a sustainable manner (i.e., replanting after every harvest), the opportunities for net carbon reductions appear to be fossil fuel substitution, rather than storage in ecosystem biomass. Our results suggest that at year 100 a total of 216 Mg C ha−1 is sequestered for afforestation/reforestation using long rotation sal (Shorea robusta Gaertn.f) species, as opposed to offset of 412 Mg C ha−1 for carbon storage and fossil fuel substitution for short rotation poplar (Populus Deltoides Marsh) plantations. The bioenergy option results in a continuous stream of about 3 Mg C ha−1 yr−1 of carbon benefits per year on forest land and 4 Mg C ha−1 yr−1 on non-forest land. Earlier studies have shown that in India waste land availability for establishing energy plantations is in the range of 9.6 to 36.5 Mha. Thus, using the 758 Tg biomass per year generated from 9.6 Mha waste land gives a mitigation potential in the range of 227 to 303 Tg C per year for carbon storage and fossil fuel substitution from poplar plantation for substituting coal based power generation. Depending upon the land availability for plantation, the potential for energy generation is in the range of 11,370 PJ, possibly amounting to a bioenergy supply of 43% of the total projected energy consumption in 2015. Further studies are needed to estimate the mitigation potential of other species with different productivities for overall estimation of the economic feasibility and social acceptability in a tropical country like India.  相似文献   

3.
Algal biofuel production and mitigation potential in India   总被引:1,自引:1,他引:0  
Energy and energy services are the backbone of growth and development in India and is increasingly dependent upon the use of fossil based fuels that lead to greenhouse gases (GHG) emissions and related concerns. Algal biofuels are being evolved as carbon (C)-neutral alternative biofuels. Algae are photosynthetic microorganisms that convert sunlight, water and carbon dioxide (CO2) to various sugars and lipids Tri-Acyl-Glycols (TAG) and show promise as an alternative, renewable and green fuel source for India. Compared to land based oilseed crops algae have potentially higher yields (5?C12 g/m2/d) and can use locations and water resources not suited for agriculture. Within India, there is little additional land area for algal cultivation and therefore needs to be carried out in places that are already used for agriculture, e.g. flooded paddy lands (20 Mha) with village level technologies and on saline wastelands (3 Mha). Cultivating algae under such conditions requires novel multi-tier, multi-cyclic approaches of sharing land area without causing threats to food and water security as well as demand for additional fertilizer resources by adopting multi-tier cropping (algae-paddy) in decentralized open pond systems. A large part of the algal biofuel production is possible in flooded paddy crop land before the crop reaches dense canopies, in wastewaters (40 billion litres per day), in salt affected lands and in nutrient/diversity impoverished shallow coastline fishery. Mitigation will be achieved through avoidance of GHG, C-capture options and substitution of fossil fuels. Estimates made in this paper suggest that nearly half of the current transportation petro-fuels could be produced at such locations without disruption of food security, water security or overall sustainability. This shift can also provide significant mitigation avenues. The major adaptation needs are related to socio-technical acceptance for reuse of various wastelands, wastewaters and waste-derived energy and by-products through policy and attitude change efforts.  相似文献   

4.
Setting a baseline for carbon stock changes in forest and land use sector mitigation projects is an essential step for assessing additionality of the project. There are two approaches for setting baselines namely, project-specific and regional baseline. This paper presents the methodology adopted for estimating the land available for mitigation, for developing a regional baseline, transaction cost involved and a comparison of project-specific and regional baseline. The study showed that it is possible to estimate the potential land and its suitability for afforestation and reforestation mitigation projects, using existing maps and data, in the dry zone of Karnataka, southern India. The study adopted a three-step approach for developing a regional baseline, namely: (i) identification of likely baseline options for land use, (ii) estimation of baseline rates of land-use change, and (iii) quantification of baseline carbon profile over time. The analysis showed that carbon stock estimates made for wastelands and fallow lands for project-specific as well as the regional baseline are comparable. The ratio of wasteland Carbon stocks of a project to regional baseline is 1.02, and that of fallow lands in the project to regional baseline is 0.97. The cost of conducting field studies for determination of regional baseline is about a quarter of the cost of developing a project-specific baseline on a per hectare basis. The study has shown the reliability, feasibility and cost-effectiveness of adopting regional baseline for forestry sector mitigation projects.
N. H. RavindranathEmail:
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5.
The global land area required to meet the German consumption of agricultural products for food and non-food use was quantified, and the related greenhouse gas (GHG) emissions, particularly those induced by land-use changes in tropical countries, were estimated. Two comprehensive business-as-usual scenarios describe the development corridor of biomass for non-food use in terms of energetic and non-energetic purposes. In terms of land use, Germany was already a net importer of agricultural land in 2004, and the net additional land required by 2030 is estimated to comprise 2.5–3.4 Mha. This is mainly due to biofuel demand driven by current policy targets. Meeting the required biodiesel import demand would result in an additional GWP of 23–37 Tg of CO2 equivalents through direct and indirect land-use changes. Alternative scenario elements outline the potential options for reducing Germany's land requirement, which reflect future global per capita availability.  相似文献   

6.
India occupies 2.4% of the world’s geographical area with a large percentage of its land under agriculture. About 228 Million hectares (Mha) of its geographical area (nearly 69%) fall within the dryland (arid, semi-arid and dry sub-humid) region. Of the total cultivated area of 142 Mha, major part of agriculture in the country is rainfed, extending to over 97 Mha and constituting nearly 68% of the net cultivated area, therefore making the agricultural sector vulnerable and exposed to the vagaries of weather conditions. Climate change adds to this dimension of stress. A strong need is felt for targeting programmes in these areas that address issues related to employing suitable soil and water conservation measures. In this context this paper seeks to examine the case for watershed development as an adaptive strategy. An examination of the possibility of fortifying the existing programme with a view to adapting to expected changes in climate in future is undertaken. Also, the possibility of watershed development integrating into a suitable mitigation strategy for the country is assessed.
Preety M. BhandariEmail:
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7.
This paper addresses methodological issues in estimating carbon (C) sequestration potential, baseline determination, additionality and leakage in Khammam district, Andhra Pradesh, southern part of India. Technical potential for afforestation on cultivable wastelands, fallow, and marginal croplands was considered for Eucalyptus clonal plantations. Field studies for aboveground and belowground biomass, woody litter, and soil organic carbon for baseline and project scenarios were conducted to estimate the carbon sequestration potential. The baseline carbon stock was estimated to be 45.3 t C/ha, predominately in soils. The additional carbon sequestration potential under the project scenario for 30 years is estimated to be 12.8 t C/ha/year inclusive of harvest regimes and carbon emissions due to biomass burning and fertilizer application. Considering carbon storage in harvested wood, an additional 45% carbon benefit can be accounted. The project scenario has a higher benefit/cost ratio compared to the baseline scenario. The initial investment cost requirement, however, is high and lack of access to investment is a significant barrier for adoption of agroforestry in the district.
N. H. RavindranathEmail:
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8.
The Regional Greenhouse Gas Initiative for the northeastern states of the U.S. allows for terrestrial carbon (C) sequestration offsets generated by afforestation activities only. This paper estimates the maximum potential quantity and associated costs of increasing the storage of carbon by afforestation of existing agricultural land in the 11 states of the Northeast United States. The focus of the work was to describe location, the quantity, and at what cost it would be economically attractive to shift agricultural production to afforestation to increase carbon storage in the region. Widely available data sets were used to (1) identify spatially-explicit areas for lower costs carbon offsets and (2) estimate carbon supply curves related to afforestation of agricultural land over three time periods (10, 20, and 40 years). Carbon accumulation and total carbon offset project costs were estimated at a county scale and combined to identify expected costs per ton of carbon dioxide equivalents (CO2e). Large variation in estimated costs per ton of CO2e are driven by varying carbon accumulation potentials and opportunity costs of taking land out of agricultural production, as well as the duration of the project activity. Results show that the lowest cost carbon offset projects will be in certain counties of Maine, Vermont, and New York. Pasture land, with lower opportunity costs, generally presents the opportunity for lower cost carbon offset projects relative to cropland. This analysis estimates that afforestation of pasture land in the northeast will not become economically attractive until the price rises above 10 per metric tonne (MT) CO < sub > 2 < /sub > e and that up to 583 million MT could be economically sequestered if the price were to rise to10 per metric tonne (MT) CO2e and that up to 583 million MT could be economically sequestered if the price were to rise to 50 per MT CO2e, based on a 40-year project life. With regard to cropland in the northeast, afforestation does not become economically advantageous for land owners until the price rises above $40 per MT CO2e. It is estimated that up to 487,000 MT could be sequestered from cropland if the price were to rise to $40 per MT CO2e. It is estimated that up to 487,000 MT could be sequestered from cropland if the price were to rise to 50 per MT CO2e, based on a 40-year project life.  相似文献   

9.
There is a need to assess climate change mitigation opportunities in forest sector in India in the context of methodological issues such as additionality, permanence, leakage and baseline development in formulating forestry mitigation projects. A case study of forestry mitigation project in semi-arid community grazing lands and farmlands in Kolar district of Karnataka, was undertaken with regard to baseline and project scenario development, estimation of carbon stock change in the project, leakage estimation and assessment of cost-effectiveness of mitigation projects. Further, the transaction costs to develop project, and environmental and socio-economic impact of mitigation project was assessed. The study shows the feasibility of establishing baselines and project C-stock changes. Since the area has low or insignificant biomass, leakage is not an issue. The overall mitigation potential in Kolar for a total area of 14,000 ha under various mitigation options is 278,380 t C at a rate of 20 t C/ha for the period 2005–2035, which is approximately 0.67 t C/ha/year inclusive of harvest regimes under short rotation and long rotation mitigation options. The transaction cost for baseline establishment is less than a rupee/t C and for project scenario development is about Rs. 1.5–3.75/t C. The project enhances biodiversity and the socio-economic impact is also significant.
N. H. RavindranathEmail:
  相似文献   

10.
Forests are believed to be a major sink for atmospheric carbon dioxide. There are 158.94 million hectares (Mha) of forests in China, accounting for 16.5% of its land area. These extensive forests may play a vital role in the global carbon (C) cycle as well as making a large contribution to the country’s economic and environmental well-being. Currently there is a trend towards increased development in the forests. Hence, accounting for the role and potential of the forests in the global carbon budget is very important.In this paper, we attempt to estimate the carbon emissions and sequestration by Chinese forests in 1990 and make projections for the following 60 years based on three scenarios, i.e. “baseline”, “trend” and “planning”. A computer model F-CARBON 1.0, which takes into account the different biomass density and growth rates for the forests in different age classes, the life time for biomass oxidation and decomposition, and the change in soil carbon between harvesting and reforestation, was developed by the authors and used to make the calculations and projections. Climate change is not modelled in this exercise.We calculate that forests in China annually accumulate 118.1 Mt C in growth of trees and 18.4 Mt in forest soils, and release 38.9 Mt, resulting in a net sequestration of 97.6 Mt C, corresponding to 16.8% of the national CO2 emissions in 1990. From 1990 to 2050, soil carbon accumulation was projected to increase slightly while carbon emissions increases by 73, 77 and 84%, and net carbon sequestration increases by −21, 52 and 90% for baseline, trend and planning scenarios, respectively. Carbon sequestration by China’s forests under the planning scenario in 2000, 2010, 2030 and 2050 is approximately 20, 48, 111 and 142% higher than projected by the baseline scenario, and 8, 18, 34 and 26% higher than by the trend scenario, respectively. Over 9 Gt C is projected to accumulate in China’s forests from 1990 to 2050 under the planning scenario, and this is 73 and 23% larger than projected for the baseline and trend scenarios, respectively. During the period 2008–2012, Chinese forests are likely to have a net uptake of 667, 565 and 452 Mt C, respectively, for the planning, trend and baseline scenarios. We conclude that China’s forests have a large potential for carbon sequestration through forest development. Sensitivity analysis showed that the biggest uncertainty in the projection by the F-CARBON model came from the release coefficient of soil carbon between periods after harvesting and before reforestation.  相似文献   

11.
In this paper, forest protection, short- and long-rotation plantations, forestregeneration, agroforestry and other activities for carbon (C) sequestration wereevaluated. China may be divided into five sub-regions, of which three fallin the main forested areas of China, i.e., the northeast, the southeast andthe southwest regions. The forestry mitigation potential in these threeregions is the subject of this paper. The Comprehensive Mitigation AssessmentProcess (COMAP) model is used to calculatethe potential for carbon mitigation and the cost-effectiveness of eachmitigation option, assuming that 60 percent of the goals of long-termforestry plans of the Chinese government could be realized. The resultsshow that the total sequestered C by the mitigation scenario between2000 and 2030 for the three regions of China will be 2093 × 106 Mg C, ofwhich 281 × 106 Mg C will occur between 2008 and 2012. The total netbiomass sequestration (difference of mitigation and baseline scenarios) from2000 to 2030 and from 2008 to 2012 is 496 × 106 Mg C and 59 × 106 Mg Crespectively. The C sequestration potential could be higher if othertwo regions are included since the forest area of the two regions amount to26.5% of total forested area, in particular, the land area suitable forforestation in the northwest accounts for 45% of the total. The activitywith least investment cost per unit of C is forest regeneration, followedby long-rotation plantation and forest conservation. The mostinvestment-intensive activity is bioenergy. The total investment for all themitigation activities is US $12.7 billion. The above figures between2008–2012 provide an upper bound on the potential for early startprojects that might be eligible for the Clean Development Mechanism(CDM). The authors would like to note that the mitigation potential andcost-effectiveness of agroforestry and bioenergy projects need to be furtherstudied.  相似文献   

12.
The role of forestry projects in carbon conservation and sequestration is receiving much attention because of their role in the mitigation of climate change. The main objective of the study is to analyze the potential of the Upper Magat Watershed for a carbon sequestration project. The three main development components of the project are forest conservation: tree plantations, and agroforestry farm development. At Year 30, the watershed can attain a net carbon benefit of 19.5 M tC at a cost of US$ 34.5 M. The potential leakage of the project is estimated using historical experience in technology adoption in watershed areas in the Philippines and a high adoption rate. Two leakage scenarios were used: baseline and project leakage scenarios. Most of the leakage occurs in the first 10 years of the project as displacement of livelihood occurs during this time. The carbon lost via leakage is estimated to be 3.7 M tC in the historical adoption scenario, and 8.1 M tC under the enhanced adoption scenario.  相似文献   

13.
Old growth mangroves in existing protected areas store more carbon than restored forests or plantations. Carbon storage in such forests has economic value independent of additionality, offering opportunities for policy makers to ensure their maintenance, and inclusion in climate change mitigation strategies. Mangrove forests of the Everglades National Park (ENP), South Florida, though protected, face external stressors such as hydrological alterations because of flooding control structures and agriculture impacts and saltwater intrusion as a result of increasing sea level rise. Moreover, decreased funding of Everglades’ restoration activities following the recent economic crisis (beginning 2008) threatens the restoration of the Greater Everglades including mangrove dominated coastal regions. We evaluate several economic and ecological challenges confronting the economic valuation of total (vegetation plus soil) organic carbon (TOC) storage in the ENP mangroves. Estimated TOC storage for this forested wetland ranges from 70 to 537 Mg C/ha and is higher than values reported for tropical, boreal, and temperate forests. We calculate the average abatement cost of C specific for ENP mangroves to value the TOC from $2–$3.4 billion; estimated unit area values are $13,859/ha–$23,728/ha. The valuation of the stored/legacy carbon is based on the: 1) ecogeomorphic attributes, 2) regional socio-economic milieu, and 3) status of the ENP mangroves as a protected area. The assessment of C storage estimates and its economic value can change public perception about how this regulating ecosystem service of ENP mangrove wetlands (144,447 ha) supports human well-being and numerous economic activities. This perception, in turn, can contribute to future policy changes such that the ENP mangroves, the largest mangrove area in the continental USA, can be included as a potential alternative in climate change mitigation strategies.  相似文献   

14.
We examine carbon (C) reference and mitigation scenarios for the Mexicanforest sector between the year 2000 and 2030. Estimates are presentedseparately for the period 2008–2012.Future C emissions and capture are estimated using a simulation modelthat: a) allocates the country land use/land cover classes among differentfuture uses and categories using demand-based scenarios for forestryproducts; b) estimates the total C densities associated to each land usecategory, and c) determines the net carbon implications of the process ofland use/cover change according to the different scenarios.The options analyzed include both afforestation/reforestation, such ascommercial, bionenergy and restoration plantations, and agroforestrysystems, and forest conservation, through the sustainable management ofnative forests and forest protection.The total mitigation potential, estimated as the difference between the totallong-term carbon stock in the reference and the mitigation scenario reaches300 × 106 Mg C in the year 2012 and increases to 1,382 × 106 Mg C in 2030. The average net sequestration in the 30 year period is 46 × 106 Mg C yr-1, or 12.5 × 106 Mg C yr-1 within the period 2008 to 2012. The costs of selected mitigation options range from 0.7–3.5 Mg C-1 to 35 Mg C-1. Some options are cost effective.  相似文献   

15.
The forest sector in the Philippines has the potential to be amajor sink for carbon (C). The present study was conducted to evaluatepotential forestry mitigation options in the Philippines using the Comprehensive Mitigation Assessment Process (COMAP)model. The baseline scenario (BAU) assumes that current trends continue upto the year 2030 (`business-as-usual'). Two mitigation scenarios wereevaluated: high scenario (HS) and low scenario (LS). The former ispatterned largely from the government's forest master plan while thelatter assumes a 50% lower success rate of the master plan.The results of the analyses show that by 2030, the total C stock of thePhilippine forest sector in the baseline scenario decreases to 814× 106 Mg C,down by 37% compared to the 1990 level. The C stocks of the HS andLS mitigation scenarios were 22% and 18% higher than the BAU,respectively. Of the mitigation options assessed, long rotation plantationsand forest protection activities produce the greatest C gain (199 and 104× 106 Mg, respectively under HS). The not present value (NPV)of benefits is highest in the bioenergyoption with $24.48 per Mg C (excluding opportunity costs) at a realdiscount rate of 12%. However, the investment and life cycle costs arealso highest using bioenergy.The study also estimated potential investments needed under the mitigationscenarios. The investment requirement for the LS amounts to $263× 106 while for the HS it is $748 × 106. Finally, policy issues anddecisions that may be useful for the Philippines to evaluate LULUCFmitigation options under the UNFCCC Kyoto Protocol, are identified anddiscussed.  相似文献   

16.
Land use, land-use change and forestry (LULUCF) projects may becomeeligible under Article 12 of the United Nations Framework Convention onClimate Change (UNFCCC) Kyoto Protocol's Clean DevelopmentMechanism (CDM). Some of the issues, which need to be addressed,include identifying the types of greenhouse gas (GHG) mitigation activitiesin LULUCF, which could be undertaken as CDM projects. Other issuesinvolve evaluating the mitigation potential and cost effectiveness of theactivities, as well as their likely socio-economic impacts and their influenceon the national carbon (C) stock. Three broad categories of mitigationactivities in LULUCF analyzed in this study include managing Cstorage, C conservation and carbon substitution. The C intensityof the activities was estimated to range from 37 to 218 Mg C per ha. The highest is in reforested land with slow growing species and the lowestin short-rotation plantations. At a real discount rate of 10%, investmentcosts required to implement the mitigation activities ranged from US$0.07 to 0.88 per Mg C, with life cycle costs ranging from US$ 0.07to 3.87 per Mg C, and benefits ranging from US$ –0.81 to 6.57 perMg C. Mitigation options with negative benefits are forest protection,reforestation, reduced impact logging and enhanced natural regeneration,while those with positive benefits are short rotation timber plantation, andbio-energy. Reforestation gave negative benefit since no revenue fromwood as trees are left in the forest for conservation, while Reduced ImpactLogging (RIL) and Enhanced Natural Regeneration (ENR)gave negative benefits because additional cost required to implement theoptions could not be compensated by the increase in round-hardwoodyield. Other factor is that the local price of round-hardwood is very low,i.e. US$ 160 per m3, while FOB price is between 250–400 US$ per m3. Total area available for implementing mitigationoptions (planting trees) in 1997 was 31 million hectares (× 106ha) (about 40% are critical lands, 35% grasslands and 25%unproductive lands).Total area being considered for implementing the options under baseline,government-plans and mitigation scenarios in the period 2000–2030 is12.6, 16.3 and 23.6 × 106 ha respectively. Furthermore, total area of production forest being considered for implementing reduced impactlogging and enrichment planting under the tree scenarios is 9, 26 and 16 × 106 ha respectively, and that for forest protection is 2.1, 3.7, 3.1× 106 ha respectively. The cumulative investment for implementingall mitigation activities in the three scenarios was estimated at 595, 892and 1026 million US$ respectively. National C stock under thebaseline scenario will continuously decline through 2030, while undergovernment-plans and mitigation scenarios the carbon stock increases. In2030, national C stock of the government and mitigation scenarios isalmost the same, 13% higher than that of baseline. However, the increasein national carbon stock in both scenarios could not offset carbon emissionsdue to deforestation.  相似文献   

17.
The methodologies for forest mitigation projects still present challenges to project developers for fulfillment of criteria within the Clean Development Mechanism (CDM) or other such mechanisms for the purpose of earning carbon credits. This paper systematically approaches the process of establishing carbon (C) stocks for baseline (BSL) and mitigation scenario (MSL) for two case studies i.e., community and farm forestry projects in Uttaranchal, India. The analysis of various interventions shows that both projects present high carbon mitigation potential. However, the C reversibility risk is lower in long-rotation pine and mixed species plantation on community lands. The project is financially viable though not highly lucrative but the carbon mitigation potential in this ‘restoration of degraded lands’ type of project is immense provided challenges in the initial phase are adequately overcome. C revenue is an essential driver for investors in community projects. The short-rotation timber species such as Eucalyptus (Eucalyptus), Poplar (Populus) have high internal rates of return (IRR) and high carbon benefit reversibility potential due to fluctuations in market prices of commodities produced. The land holdings are small and bundling is desired for projects to achieve economies of scale. The methodological concerns such as sampling intensities, monitoring methodologies, sharing of benefits with communities and bundling arrangements for projects need further research to make these projects viable.  相似文献   

18.
In this study we used high resolution (20 m) land cover maps to derive detailed information on land cover structure within the classes of a regional medium resolution (500 m) land cover map. This enabled improved biomass estimation for the medium resolution land cover classes. Although our results suggested that land cover maps based merely on medium resolution remote sensing data can be used to monitor the extent of forest cover, they also showed that these maps alone are not sufficient to produce reliable regional estimates on above ground biomass in insular Southeast Asia. A quarter of the study area was covered by sub-pixel size (500 m) mosaic of various land cover types containing 14% of biomass. In total, non-forest areas covered over 60% of the study area and included 43% of biomass. In these areas, highly fragmented within class land cover structure was shown to significantly affect biomass estimates. Therefore we conclude that forest/land cover monitoring based merely on medium resolution remote sensing data can no longer be used to sufficiently quantify carbon fluxes connected to land cover changes in insular Southeast Asia, but multi-resolution approaches are needed to perform this task.  相似文献   

19.
研究土地利用时空演变对生态系统碳储量的影响,对研究区未来的国土空间规划以及减排增汇提供理论依据.基于1985、1995、2005、2015和2020年这5期土地利用数据,结合InVEST模型分析了研究区碳储量时空变化,运用PLUS模型预测研究区2035年自然发展情景、耕地保护情景、生态保护情景以及耕地和生态双保护情景土地利用变化并估算不同情景下的生态系统碳储量.结果表明:①1985~2020年研究区耕地面积持续减少,2015~2020年土地利用变化较快,综合土地利用动态度达到了34.62 %;②1985~2020年碳储量呈下降趋势,减少1.55×105 t,其中在2005~2015年间,碳储量减少了1.22×105 t,年均减少量达1.22×104 t;③碳储量较高区域分布在研究区的东部,碳储量较低区域分布在研究区中部和西北部;耕地碳储量占比从66.89 %下降到57.73 %,但耕地仍是研究区最主要的碳库;其他地类向草地和林地转化有利于生态系统碳储量的增加;④2035年,自然发展情景、耕地保护情景、生态保护情景以及双保护情景下的碳储量分别为81.77×105 、82.45×105、82.82×105和82.51×105 t.  相似文献   

20.
There was a widespread misconception about the causes of vegetation and land fires in Indonesia. At a certain point, the public perceived that fires and the associated haze pollution were primarily caused by smallholders' agricultural activities. In fact, there was a variety of land-use activities including large-scale land clearing following deforestation for further land development. El Niño events and the associated dry weather were sometimes quoted by officials and the media as the cause of fires. The fire episodes from 1980 to 2000 were analysed in connection with climate anomalies and the implementation of land-use policies related to forest conversions. The analysis employs long-term climatic and sea surface temperature data to reconstruct climate distributions and anomalies including Southern Oscillation Index (SOI), Sea Surface Temperature (SST) and Outgoing Long-wave Radiation (OLR). In this study, the terrestrial carbon emissions from vegetation fires were estimated based on official statistical data on area burnt. The possible incentives for sustainable land management were discussed in the light of fire prevention. The underlying cause neglected in the discussion of Indonesian vegetation fires was forest and land development policy. Legitimated in the early 1980s, it drove massive forest conversions and the use of fires for land clearing. El Niño Southern Oscillation (ENSO) provided dry weather suitable for biomass burning and widespread fire, but it was hardly the cause of fires. The estimate of area burnt in the big fires in 1997 was about 11.6 Mha, resulting in carbon release of 1.45 Gt, equivalent to 0.73 ppmv of CO2, or almost half the annual global atmospheric CO2 growth. Based on the current carbon market price such emissions by the 1997 fire episode were worth around US$ 3.6 billion.  相似文献   

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