共查询到20条相似文献,搜索用时 15 毫秒
1.
Due to impacts of albedo on climate change, benefits of afforestation/reforestation regimes are under debate. In this paper we investigate how to incorporate albedo changes in a carbon accounting tool to show the net effect of land use change on the climate. Using a study area in southern Europe, albedo and carbon sequestration modelling results are linked to determine the combined radiative forcing balance. The results show that under specific circumstances afforestation/reforestation measures may not automatically have positive impacts in a global warming context because the cooling effect of most of the carbon sequestered is neutralized by the warming effect of albedo changes. However, sensitivity analyses lead to the conclusion that improved albedo data from satellite images (MODIS) could influence and enhance outputs significantly. The paper points out that accounting based exclusively on GHG units does not, in the case of land use change, reflect the entire picture. It is highly recommended that in future global warming impacts of land use systems and biogenic products (e.g. solid biomass, liquid biofuels) should be studied using life cycle assessments (LCA) and should include these additional—non-GHG effects—on climate change. 相似文献
2.
Forests play an important role in the global carbon cycle as both a source and sink of carbon. The carbon stock in a forest is affected by climate, tree species and forest management. The community forestry program of Nepal has been successful in reviving degraded forest patches in the Mid-hills but there is a lack of information whether mixed or pine plantations store more carbon. This study estimated and compared carbon stocks in mixed and pine-dominated forest stands within the Gwalinidaha Community Forest of Lalitpur District, Central Nepal. Carbon components considered include tree biomass carbon, root biomass carbon, litter biomass carbon and soil organic carbon. Total carbon stock of the forest is estimated to be 2,250.24 tons with average carbon stock of 166.68 tons/ha. Total carbon stock per hectare was found to be higher in the pine-dominated forest as compared to mixed forest due to the larger tree biomass although the litter carbon and soil organic carbon estimates are higher in the latter. The Community Forestry of Nepal has a huge potential for carbon storage and the pine-dominated forest has a greater carbon stock than mixed forest. 相似文献
3.
Pau Brunet-Navarro Frank J. Sterck Jordi Vayreda Jordi Martinez-Vilalta Godefridus M.J. Mohren 《Annals of Forest Science》2016,73(4):1025-1034
Key message
Self-thinning lines are species- and climate-specific, and they should be used when assessing the capacity of different forest stands to increase biomass/carbon storage.Context
The capacity of forests to store carbon can help to mitigate the effects of atmospheric CO2 rise and climate change. The self-thinning relationship (average size measure ~ stand density) has been used to identify the potential capacity of biomass storage at a given density and to evaluate the effect of stand management on stored carbon. Here, a study that shows how the self-thinning line varies with species and climate is presented.Aims
Our main objective is thus testing whether species identity and climate affect the self-thinning line and therefore the potential amount of carbon stored in living biomass.Methods
The Ecological and Forest Inventory of Catalonia was used to calculate the self-thinning lines of four common coniferous species in Catalonia, NE Iberian Peninsula (Pinus halepensis, Pinus nigra, Pinus sylvestris and Pinus uncinata). Quadratic mean diameter at breast height was chosen as the average size measure. The self-thinning lines were used to predict the potential diameter at a given density and study the effect of environmental variability.Results
Species-specific self-thinning lines were obtained. The self-thinning exponent was consistent with the predicted values of ?3/2 and ?4/3 for mass-based scaling for all species except P. sylvestris. Species identity and climatic variability within species affected self-thinning line parameters.Conclusion
Self-thinning lines are species-specific and are affected by climatic conditions. These relationships can be used to refine predictions of the capacity of different forest stands to increase biomass/carbon storage.4.
Bryanna Thiel Maja Krzic Sarah Gergel Christine Terpsma Andrew Black Rachhpal Jassal Sean M. Smukler 《Agroforestry Systems》2017,91(6):1139-1156
Planting hedgerows on farm field edges can help mitigate greenhouse gas (GHG) emissions from agricultural landscapes by sequestering carbon (C) in woody biomass and in soil. Sequestration rates however, must be assessed in terms of their overall global warming potential (GWP) which must also consider GHG emissions. The objectives of this study were to (1) compare carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) emissions from two types of hedgerows and adjacent annual agricultural production fields, and 2) better understand how climate, soil properties and plant species configurations affect hedgerow GHG emissions. At eight study sites in the lower Fraser River delta of British Columbia, we measured emissions from soil in both planted (P-Hedgerow) and remnant hedgerows (R-Hedgerow), as well as in adjacent annual crop production fields over 1 year using a closed-static chamber method. CO2 emissions were 59 % higher in P-Hedgerow than R-Hedgerow, yet there were no significant differences of relative emissions of CH4 and N2O. The environmental variables that explained the variation in emissions differed for the three GHGs. CO2 emissions were significantly correlated with soil temperature. CH4 and N2O and emissions were marginally significantly correlated with soil organic carbon (SOC) and soil water-filled pore space (WFPS), respectively. Emissions were not significantly correlated with hedgerow plant species diversity. While hedgerows sequester carbon in their woody biomass, we demonstrated that it is critical to measure hedgerow emissions to accurately ascertain their overall GHG mitigation potential. Our results show that there are no CO2e emission differences between the management options that plant new diverse hedgerows or conserve existing hedgerows. 相似文献
5.
森林生态系统碳储量及碳通量遥感监测研究进展 总被引:1,自引:2,他引:1
在全球CO2浓度持续增加导致气候变暖的背景下,森林生态系统碳储量及碳通量遥感大尺度监测成为关注热点。文中深入分析了当前国内外卫星遥感观测技术对森林碳循环评估的2种途径:1)基于遥感手段估算森林生物量并推算森林碳储量,通过碳储量变化确定森林生态系统的CO2通量。归纳各类森林生物量遥感估算方法的原理及优缺点,系统评述各类方法在大区域森林碳储量估算中存在的不确定性。2)基于CO2温室气体观测卫星遥感数据,定量监测森林生态系统与大气CO2通量,基于交换的CO2通量推算森林碳储量变化。归纳遥感手段观测森林生态系统与大气CO2通量的主要数据、方法及优缺点,系统评述各类数据及方法在森林CO2通量时空变化特征监测、森林碳储量估算等方面取得的进展,重点分析专用CO2浓度监测卫星数据,尤其是我国自主碳卫星数据在CO2柱浓度反演算法研究以及不同数据源之间的对比、验证和同化研究等方面取得的进展,总结专用温室气体遥感观测数据在森林碳储量及碳通量监测方面的优势。提出利用遥感手段进行森林生态系统碳循环定量监测的研究展望。 相似文献
6.
This article examines alternative forest harvesting regimes when ecosystem services in terms of water quality, biodiversity conservation and climate change mitigation are included in the analysis. The harvesting regimes are whole-tree harvesting with stump removal and conventional stem-only harvesting. The harvesting regimes are evaluated under two alternative climate policy contexts. The first alternative is a carbon neutral bioenergy policy, which assumes the carbon dioxide (CO2) neutrality of bioenergy and produces substitution benefits, as bioenergy replaces fossil fuels. The second alternative climate policy, a carbon non-neutral bioenergy policy, takes into account the fact that bioenergy causes carbon dioxide emissions, producing substitution costs, and that harvested woody biomass affects the ability of a forest to act as a carbon sink. We extend the traditional Faustmann (1849) rotation model to include nutrient load damage, biodiversity benefits, and climate impacts. The empirical analysis is based on Finnish data from a catchment experiment carried out on drained peatland forests. The empirical results show that under a carbon neutral bioenergy policy, whole-tree harvesting with stump removal produces the highest net social benefits. However, if a carbon non-neutral bioenergy policy is assumed, the net social benefits are greater under stem-only harvesting. 相似文献
7.
Gyungsoo Cha 《Journal of Forest Research》1997,2(3):147-152
Change in potential natural vegetation (PNV) distribution associated with climate change due to the doubling atmospheric carbon
dioxide (2×CO2) was estimated with a global natural vegetation mapping system based on the modified Kira scheme to the globe and the continents.
With an input of widely-distributed global climate data, the system interpolates data onto a 1° latitude by 1° longitude grid
over the globe, generates estimates of vegetation type, and produces a composite PNV map. The input climate data corresponding
to the 1×CO2 and 2×CO2 consists of observations prior to AD 1958 at 2,001 weather stations worldwide and the 2×CO2 simulation output from the Japan Meteorological Research Institue's General Circulation Model, respectively. As a result
of the simulated global warming, the vegetation zones expanded mostly from the tropics toward the poles. PNV area changed
by 6.98 billion (G) ha of the total land area (15.04 Gha) and potential forest area corresponding to the closed forest and
open forest (woodland) reached 9.74 Gha with the increase of 1.29 Gha. The potential forest area in Europe had obvious advantages
to the climate change accompanied with the increase of actual forest area. Although the actual forest area has decreased in
North America and Asia, the potential forest area in these continents also benefitted from the climate change. In the end,
the remaining continents tended to bear the brunt of the climate change. 相似文献
8.
9.
10.
R. K. Dixon 《Agroforestry Systems》1995,31(2):99-116
The prominent role of forestry and agroforestry systems in the flux and long-term storage of carbon (C) in the terrestrial biosphere has increased global interest in these land-use options to stabilize greenhouse gas (GHG) emissions. Preliminary assessments suggest that some agroforestry systems (e.g., agrosilvicultural) can be CO2 sinks and temporarily store C, while other systems (e.g., ruminant-based silvopastoral systems) are probably sources of GHG (e.g., CH4).Agroforestry systems can be significant sources of GHG emissions, especially at low latitudes. Practices such as tillage, burning, manuring, chemical fertilization, and frequent disturbance can lead to emission of CO2, CH4, and N2O from soils and vegetation to the atmosphere. Establishment and management of agroforestry systems incompatible with prevailing edaphic and climatic conditions can accelerate soil GHG emissions. Non-sustainable agroforestry systems are quickly degraded, and woody and herbaceous crops can become significant GHG sources. Silvopastoral systems can result in soil compaction and erosion with significant loss of labile C and N compounds to the atmosphere. Ruminant-based silvopastoral systems and rice paddy agrisilvicultural systems are well documented sources of CH4 which significantly contribute to the global CH4 budget.Early assessments of national and global terrestrial CO2 sinks reveal two primary beneficial attributes of agroforestry systems: 1) direct near-term C storage (decades to centuries) in trees and soils, and, 2) potential to offset immediate GHG emissions associated with deforestation and subsequent shifting agriculture. Within the tropical latitudes, it is estimated that one ha of sustainable agroforestry can provide goods and services which potentially offset 5–20 ha of deforestation. At a global scale, agroforestry systems could potentially be established on 585–1275×106 ha of technically suitable land, and these systems could store 12–228 (median 95) Mg C ha–1 under current climate and edaphic conditions.The US Government right to retain a non-exclusive, royalty free licence in and to any copyright is acknowledged. 相似文献
11.
Forest management activities may help reduce global net CO2 concentrations by capturing and storing atmospheric CO2. Research related to carbon sequestration potential of plantations in North America has focused predominantly on conifers, with relatively little emphasis thus far on temperate deciduous forest tree species. American chestnut (Castanea dentata (Marsh.) Borkh.), a former dominant tree species in eastern North America until its demise associated with the introduced chestnut blight (Cryphonectria parasitica (Murr.) Barr.), is a temperate deciduous species that holds promise for future carbon sequestration programs with expected availability of blight-resistant backcross hybrids. We quantified aboveground biomass and bole carbon of American chestnut interplanted with black walnut (Juglans nirga L.) and northern red oak (Quercus rubra L.) across four blight-free experimental sites varying in site quality and/or age (8, 8, 12, and 19 years) isolated from the native American chestnut range in the Coulee Region of southwestern Wisconsin, USA. American chestnut exhibited more rapid growth and greater aboveground biomass and bole carbon than either of the other interplanted species. Aboveground biomass ranged from 46.9, 60.7, 55.0, and 179.9 Mg ha−1 for the 8-, 8-, 12-, and 19-year-old sites, respectively, while bole carbon content ranged from 13.6, 18.6, 14.1, and 60.1 Mg ha−1 for the 8-, 8-, 12-, and 19-year-old sites, respectively. Cross-referencing our data to studies conducted within this same physiographic region using other important forestry species (i.e., Populus tremuloides Michx., Pinus resinosa Ait., and Pinus strobus L.) showed that American chestnut compared favorably in growth and carbon uptake. Incorporating American chestnut into carbon sequestration plantations provides additional ecological and economic benefits associated with consistent production of quality nuts for wildlife, valuable timber, and contribution toward species restoration. Our data lend support to building evidence demonstrating rapid and sustained growth of American chestnut and the potential role of plantation-grown American chestnut in helping to mitigate climate change through carbon sequestration. 相似文献
12.
DAI Guangcui Forestry Economics Development Research Center State Forestry Administration Beijing P.R.China 《中国林业科技(英文版)》2010,(1):8-13
Forests have multiple benefits and functions, including mitigation of climate change. The impacts of forests on the global carbon cycle include forests as carbon sinks, wood-based products as carbon sinks, bio-energy, and production and use of non-timber products. In the past decades, forest cover of China has increased from 8.6% to 18.21% by large-scale afforestation and conversion of cropland into forests. Forest biomass carbon (C) stock increased from 4.3 Pg C (1 Pg C = 1 015 g C) in the early 1980s to 5... 相似文献
13.
研究了传统耕作和保护性耕作2种方式对玉米农田生态系统各碳库的影响规律,结果表明:与传统耕作方式相比,保护性耕作能有效提高玉米各器官生物量,整株生物量平均提高了2.15倍,各器官有机碳含量平均提高了11.4%,单株碳储量提高了2.56倍;保护性耕作能有效提高0~30 cm各土层有机碳储量,对0~10 cm土层范围内土壤有机碳含量影响程度明显,其碳含量较传统耕作提高近1倍;实施保护性耕作后,玉米农田生态系统各碳库碳储量呈现明显的增加趋势,玉米农田生态系统地上碳库、根系碳库、土壤碳库和总碳库碳储量分别达到了1 431.62 kg/hm2、364.79 kg/hm2、27 667 kg/hm2、29 463.66 kg/hm2,比传统耕作分别提高了263.6%、228.6%、62.7%、68.3%。 相似文献
14.
《Scandinavian Journal of Forest Research》2012,27(4):326-335
Accurate biomass measurements and analyses are critical components in quantifying carbon stocks and sequestration rates, assessing potential impacts due to climate change, locating bio-energy processing plants, and mapping and planning fuel treatments. To this end, biomass equations will remain a key component of future carbon measurements and estimation. As researchers in biomass and carbon estimation, we review the present scenario of aboveground biomass estimation, focusing particularly on estimation using tree-level models and identify some cautionary points that we believe will improve the accuracy of biomass and carbon estimates to meet societal needs. In addition, we discuss the critical challenges in developing or calibrating tree biomass models and opportunities for improved biomass. Some of the opportunities to improve biomass estimate include integration of taper and other attributes and combining different data sources. Biomass estimation is a complex process, when possible, we should make use of already available resources such as wood density and forest inventory databases. Combining different data-sets for model development and using independent data-sets for model verification will offer opportunities to improve biomass estimation. Focus should also be made on belowground biomass estimation to accurately estimate the full forest contribution to carbon sequestration. In addition, we suggest developing comprehensive biomass estimation methods that account for differences in site and stand density and improve forest biomass modeling and validation at a range of spatial scales. 相似文献
15.
H. Tømmervik B. Johansen J.Å. Riseth S.R. Karlsen B. Solberg K.A. Høgda 《Forest Ecology and Management》2009
Birch forests cover large areas of the northern Fennoscandia and the mountain birch (Betula pubescens ssp. czerepanovii) often forming the altitudinal and Arctic forest and tree lines. Interpreting the factors leading to landscape changes in mountain birch forest involves disturbance from anthropogenic use and climate as important factors. Using vegetation maps based on aerial photographs and satellite images from 7 years in combination with statistical data and ground estimation data of biomass in the period 1957–2006, we were able to assess the transitions among mountain heaths and different types of forest, the displacement of the altitudinal forest line and hence the change in biomass. The tree biomass as well as the growing stock for birch in Finnmarksvidda doubled in the period 1957–2006. Only lichen biomass has been significantly reduced in the period 1957 to 2000, with a subsequent slight increase of lichen biomass in the period 2000 to 2006. The results presented in this paper show significant and positive relationships between measured tree biomass and the increase in reindeer population in the period 1957–2006 in the study area. The hypothesis concerning the removal of the “lichen barrier effect” by heavy reindeer grazing which leads to increased success for birch seeds to germinate and sprout is therefore considered to be valid. However, also, climate change effects like increased precipitation, moth attacks, freezing and thawing events during winter and long-transported air pollution (e.g. nitrogen) may also have reinforced the changes in biomass. Climatic variables from regional weather stations for the period 1955–2006 did not, however, reveal any consistent change except for that the increased snow depth had a negative impact on the reindeer population while increase in snow depth hindering the reindeer in grazing seemed to have a positive impact on the lichen biomass. The ongoing development of increased forest cover and hence elevated forest line will lead to reduction of open habitats, and hence decreased grazing accessibility for the reindeer. The effects on forestry and carbon sequestration are also discussed, and here one of the suggestions is to let the northern birch forests act as carbon sinks contributing to the reduction of total net emission of CO2 in the Nordic countries. Land use like reindeer husbandry has shown to strongly affect relationships between ecological processes like tree-growth and climate. Moreover, reindeer husbandry is such a widespread human activity in the arctic and boreal region that it might affect the global carbon budget. 相似文献
16.
Carbon storage in evergreen broad-leaf forests in mid-subtropical region of China at four succession stages 总被引:1,自引:0,他引:1
To better understand the effect of forest succession on carbon sequestration, we investigated carbon stock and allocation of evergreen broadleaf forest, a major zonal forest in subtropical China. We so... 相似文献
17.
18.
大气CO2增长和气候变化对森林的影响研究进展 总被引:25,自引:0,他引:25
本文概述了过去10多年中,国内外大气CO2增长对林木影响及气候变化对森林影响方面的研究结果。内容包括:在大气CO2倍增的情况下,净光合作用和生物产量、气孔的水气传导率及水分利用效率的变化;CO2与温度的共同影响及与养分供应的共同影响;暗呼吸,根茎比,光合适应现象。本文还介绍了气候变化对植被带、个别森林影响的宏观研究情况,以及古气候与古植被相互关系的研究。 相似文献
19.
Forest carbon storage in the northeastern United States: Net effects of harvesting frequency,post-harvest retention,and wood products 总被引:1,自引:0,他引:1
Temperate forests are an important carbon sink, yet there is debate regarding the net effect of forest management practices on carbon storage. Few studies have investigated the effects of different silvicultural systems on forest carbon stocks, and the relative strength of in situ forest carbon versus wood products pools remains in question. Our research describes (1) the impact of harvesting frequency and proportion of post-harvest structural retention on carbon storage in northern hardwood-conifer forests, and (2) tests the significance of including harvested wood products in carbon accounting at the stand scale. We stratified Forest Inventory and Analysis (FIA) plots to control for environmental, forest structural and compositional variables, resulting in 32 FIA plots distributed throughout the northeastern U.S. We used the USDA Forest Service's Forest Vegetation Simulator to project stand development over a 160 year period under nine different forest management scenarios. Simulated treatments represented a gradient of increasing structural retention and decreasing harvesting frequencies, including a “no harvest” scenario. The simulations incorporated carbon flux between aboveground forest biomass (dead and live pools) and harvested wood products. Mean carbon storage over the simulation period was calculated for each silvicultural scenario. We investigated tradeoffs among scenarios using a factorial treatment design and two-way ANOVA. Mean carbon sequestration was significantly (α = 0.05) greater for “no management” compared to any of the active management scenarios. Of the harvest treatments, those favoring high levels of structural retention and decreased harvesting frequency stored the greatest amounts of carbon. Classification and regression tree analysis showed that management scenario was the strongest predictor of total carbon storage, though site-specific variables were important secondary predictors. In order to isolate the effect of in situ forest carbon storage and harvested wood products, we did not include the emissions benefits associated with substituting wood fiber for other construction materials or energy sources. Modeling results from this study show that harvesting frequency and structural retention significantly affect mean carbon storage. Our results illustrate the importance of both post-harvest forest structure and harvesting frequency in carbon storage, and are valuable to land owners interested in managing forests for carbon sequestration. 相似文献
20.
Guishan Cui Hanbin Kwak Sungho Choi Moonil Kim Chul-Hee Lim Woo-Kyun Lee Joon-Soon Kim Yeora Chae 《林业研究》2016,27(3):489-503
This study demonstrated a framework to assess vulnerability of forests to climate change. We focused on how alterations of temperature and precipitation might affect forest type distributions and carbon-related functions. In particular, our framework considered three sectors of forest type distribution, net primary production, and soil carbon storage. Future projections were derived from mechanistic models for South Korean forests under the A1B scenarios of the intergovernmental panel on climate change. Forest type distributions were simulated by the Hydrological and thermal analogy group model, while the MAPSS and CENTURY1 models estimated forest carbon flux/storage. We quantified normalized vulnerability indices for each sector. Our results indicate that the overall vulnerability of forest type distribution is greater in the west central regions and southeastern inlands. The vulnerabilities of carbon flux/storage show that net primary production of South Korean forests is relatively less susceptible to climate change, but a highly vulnerable area of soil carbon storage mainly spreads from the west central to the south east region. The spatio-temporal vulnerability map with a synoptic overview from this study might be useful for policy makers in preparing adaptive measures and identifying management priorities. 相似文献