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1.
A study was conducted to assess carbon stocks in various forms and land-use types and reliably estimate the impact of land use on C stocks in the Nam Yao sub-watershed (19°05'10"N, 100°37'02"E), Thailand. The carbon stocks of aboveground, soil organic and fine root within primary forest, reforestation and agricultural land were estimated through field data collection. Results revealed that the amount of total carbon stock of forests (357.62 ± 28.51 Mg·ha-1, simplified expression of Mg (carbon)·ha-1) was significantly greater (P< 0.05) than the reforestation (195.25 ±14.38 Mg·ha-1) and the agricultural land (103.10±18.24 Mg·ha-1). Soil organic carbon in the forests (196.24 ±22.81 Mg·ha-1) was also significantly greater (P< 0.05) than the reforestation (146.83± 7.22 Mg·ha-1) and the agricultural land (95.09 ± 14.18 Mg·ha-1). The differences in carbon stocks across land-use types are the primary consequence of variations in the vegetation biomass and the soil organic matter. Fine root carbon was a small fraction of carbon stocks in all land-use types. Most of the soil organic carbon and fine root carbon content was found in the upper 40-cm layer and decreased with soil depth. The aboveground carbon(soil organic carbon: fine root carbon ratios (ABGC: SOC: FRC), was 5:8:1, 2:8:1, and 3:50:1 for the forest, reforestation and agricultural land, respectively. These results indicate that a relatively large proportion of the C loss is due to forest conversion to agricultural land. However, the C can be effectively recaptured through reforestation where high levels of C are stored in biomass as carbon sinks, facilitating carbon dioxide mitigation.  相似文献   

2.
We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,China.According to the definitions of the forest inventory,Henan forests were categorized into five groups: forest stands,economic forests,bamboo forests,open forests,and shrub forests.We estimated biomass carbon in forest stands for each inventory period by using the continuous biomass expansion factor method.We used the mean biomass density method to estimate carbon stocks in economic,bamboo,open and shrub forests.Over the 60-year period,total forest vegetation carbon storage increased from34.6 Tg(1 Tg = 1×10~(12)g) in 1949 to 80.4 Tg in 2008,a net vegetation carbon increase of 45.8 Tg.By stand type,increases were 39.8 Tg in forest stands,5.5 Tg in economic forests,0.6 Tg in bamboo forests,and-0.1 Tg in open forests combine shrub forests.Carbon storageincreased at an average annual rate of 0.8 Tg carbon over the study period.Carbon was mainly stored in young and middle-aged forests,which together accounted for 70–88%of the total forest carbon storage in different inventory periods.Broad-leaved forest was the main contributor to forest carbon sequestration.From 1998 to 2008,during implementation of national afforestation and reforestation programs,the carbon storage of planted forest increased sharply from 3.9 to 37.9 Tg.Our results show that with the growth of young planted forest,Henan Province forests realized large gains in carbon sequestration over a 60-year period that was characterized in part by a nation-wide tree planting program.  相似文献   

3.
Carbon stock estimation was conducted in tree species of Sem Mukhem sacred forest in district Tehri of Garhwal Himalaya, Uttarakhand, India. This forest is dedicated to Nagraj Devta and is dominated by tree species, including Quercus floribunda, Quercus semecarpifolia and Rhododendron arboreum. The highest values of below ground biomass density, total biomass density and total carbon density were (34.81±1.68) Mg·ha?1, (168.26±9.04) Mg·ha?1 and (84.13±4.18) Mg·ha?1 for Pinus wallichiana. Overall values of total biomass density and total carbon density calculated were 1549.704 Mg·ha?1 and 774.77 Mg·ha?1 respectively. Total value of growing stock volume density for all species was 732.56 m3·ha?1 and ranged from (144.97±11.98) m3·ha?1 for Pinus wallichiana to (7.78±1.78) m3·ha?1 for Benthamidia capitata.  相似文献   

4.
A forest carbon (C) sequestration project was conducted to evaluate the economic incentives that would be required by landowners to engage in C trading under different management regimes. Costs associated with joint management for C sequestration and timber would be valuable for establishing sound forest C trading systems. In this study, we calculated the C yield and amortized value of three Wyoming, ponderosa pine stands. The management practices examined were, unmanaged, even-aged (regeneration after clear-cut) and uneven-aged (selectively harvested). Costs and revenues associated with three stands were converted into 2006 real dollars using the all commodity producer price index to facilitate a comparison among the net revenues of three stands. Net revenues were annualized using a conservative annual interest rate of 4.5%. Our even-aged stand had the highest annual average C yield of 2.48 Mg·ha−1·a1, whereas, the uneven-aged stand had the lowest C accumulation (1.98 Mg·ha−1·a−1). Alternatively, the even-aged stand had the highest amortized net return of $276·ha−1·a−1 and the unmanaged stand had the lowest net return of $276·ha−1·a−1 and the unmanaged stand had the lowest net return of 64 ·ha−1·a−1. On the plots examined, an annual payment of $22 for each additional Mg of C sequestered would encourage a change from uneven aged management to an unmanaged stand that sequesters additional C, in the absence of transactions costs.  相似文献   

5.
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   

6.
《Southern Forests》2013,75(4):305-315
Land-use intensification and declines in vegetative cover are considered pervasive threats to forests and biodiversity globally. The small extent and high biodiversity of indigenous forests in South Africa make them particularly important. Yet, relatively little is known about their rates of use and change. From analysis of past aerial photos we quantified rates of forest cover change in the Matiwane forests of the Wild Coast, South Africa, between 1942 and 2007, as well as quantified above and belowground (to 0.5?m depth) carbon stocks based on a composite allometric equation derived for the area. Rates of forest conversion were spatially variable, with some areas showing no change and others more noticeable changes. Overall, the net reduction was 5.2% (0.08% p.a.) over the 65-year period. However, the rate of reduction has accelerated with time. Some of the reduction was balanced by natural reforestation into formerly cleared areas, but basal area, biomass and carbon stocks are still low in the reforested areas. The total carbon stock was highest in intact forests (311.7 ± 23.7 Mg C ha?1), followed by degraded forests (73.5 ± 12.3 Mg C ha?1) and least in regrowth forests (51.2 ± 6.2 Mg C ha?1). The greatest contribution to total carbon stocks was soil carbon, contributing 54% in intact forests, and 78% and 68% in degraded and regrowth forests, respectively. The Matiwane forests store 4.78 Tg C, with 4.7 Tg C in intact forests, 0.06 Tg C in degraded forests and 0.02 Tg C in regrowth forests. The decrease in carbon stocks within the forests as a result of the conversion of the forest area to agricultural fields was 0.19 Tg C and approximately 0.0003 Tg C was released through harvesting of firewood and building timber.  相似文献   

7.
Forest ecosystems play a major role in atmospheric carbon sequestration and emission. Comparable organic carbon stock estimates at temporal and spatial scales for all forest pools are needed for scientific investigations and political purposes. Therefore, we developed a new carbon stock (CS) estimation procedure that combines forest inventory and soil and litter geodatabases at a regional scale (southern Belgium). This procedure can be implemented in other regions and countries on condition that available external carbon soil and litter data can be linked to forest inventory plots. The presented procedure includes a specific CS estimation method for each of the following forest pools and subpools (in brackets): living biomass (aboveground and belowground), deadwood (dead trees and snags, coarse woody debris and stumps), litter, and soil. The total CS of the forest was estimated at 86 Tg (185 Mg ha?1). Soil up to 0.2 m depth, living biomass, litter, and deadwood CSs account, respectively, for 48, 47, 4, and 1 % of the total CS. The analysis of the CS variation within the pools across ecoregions and forest types revealed in particular that: (1) the living biomass CS of broadleaved forests exceeds that of coniferous forests, (2) the soil and litter CSs of coniferous forest exceed those of broadleaved forests, and (3) beech stands come at the top in carbon stocking capacity. Because our estimates differ sometimes significantly from the previous studies, we compared different methods and their impacts on the estimates. We demonstrated that estimates may vary highly, from ?16 to +12 %, depending on the selected methods. Methodological choices are thus essential especially for estimating CO2 fluxes by the stock change approach. The sources of error and the accuracy of the estimates were discussed extensively.  相似文献   

8.
The effect of forest conservation on the organic carbon (C) stock of temperate forest soils is hardly investigated. Coarse woody debris (CWD) represents an important C reservoir in unmanaged forests and potential source of C input to soils. Here, we compared aboveground CWD and soil C stocks at the stand level of three unmanaged and three adjacent managed forests in different geological and climatic regions of Bavaria, Germany. CWD accumulated over 40–100 years and yielded C stocks of 11 Mg C ha?1 in the unmanaged spruce forest and 23 and 30 Mg C ha?1 in the two unmanaged beech–oak forests. C stocks of the organic layer were smaller in the beech–oak forests (8 and 19 Mg C ha?1) and greater in the spruce forest (36 Mg C ha?1) than the C stock of CWD. Elevated aboveground CWD stocks did not coincide with greater C stocks in the organic layers and the mineral soils of the unmanaged forests. However, radiocarbon signatures of the O e and O a horizons differed among unmanaged and managed beech–oak forests. We attributed these differences to partly faster turnover of organic C, stimulated by greater CWD input in the unmanaged forest. Alternatively, the slower turnover of organic C in the managed forests resulted from lower litter quality following thinning or different tree species composition. Radiocarbon signatures of water-extractable dissolved organic carbon (DOC) from the top mineral soils point to CWD as potent DOC source. Our results suggest that 40–100 years of forest protection is too short to generate significant changes in C stocks and radiocarbon signatures of forest soils at the stand level.  相似文献   

9.
Community forests of developing countries are eligible to participate in the Reducing Emissions from Deforestation and Forest Degradation (REDD+) scheme. For this, estimation of carbon stock and the sequestration is essential. The carbon stock in the living biomass of nine community managed Shorea robusta forests of the mid hill regions of central Nepal (managed for 4–29 yr) were estimated. The carbon stock of trees and shrubs was estimated using an allometric equation while the biomass of herbaceous vegetation was estimated by the harvest method. The carbon stock in the living biomass of the studied forests ranged from 70–183 Mg ha?1(mean: 120 Mg ha?1) and it increased with increasing soil organic carbon. However, the carbon stock did not vary significantly with species richness and litter cover. The biomass and carbon stock in the forests managed for >20 yr were significantly higher than in the forests managed for < 20 yr. The carbon stock increased with the management duration (p < .05) with sequestration rate of 2.6 Mg C ha?1 yr?1. The local management has had positive effects on the carbon stock of the forests and thus the community forests have been acting as a sink of the atmospheric CO2. Therefore, the community managed forests of Nepal are eligible to participate in the REDD+ scheme.  相似文献   

10.
Aboveground biomass and carbon stock in the largest sacred grove of Manipur was estimated for trees with diameter [10 cm at 1.37 m height.The aboveground biomass,carbon stock,tree density and basal area of the sacred grove ranged from 962.94 to 1130.79 Mg ha~(-1),481.47 to 565.40 Mg ha~(-1) C,1240 to 1320 stem ha~(-1) and79.43 to 90.64 m~2 ha~(-1),respectively.Trees in diameter class of 30–40 cm contributed the highest proportion of aboveground biomass(22.50–33.73%).The aboveground biomass and carbon stock in research area were higher than reported for many tropical and temperate forests,suggesting a role of spiritual forest conservation for carbon sink management.  相似文献   

11.
湖南主要森林类型碳汇功能及其经济价值评价   总被引:9,自引:0,他引:9  
利用湖南省森林资源主要数据汇编(1999—2003年),依据不同森林类型生物量与蓄积量之间的回归方程,对湖南省几种主要森林类型的生物量和碳贮量进行了推算,分析了不同林龄结构的碳密度以及天然林与人工林的碳贮量,并对整个湖南省的森林经济价值进行估算。结果表明:湖南省主要森林类型的总碳贮量为94.935 Tgc,碳汇总经济价值为70 723.26万元,固定CO2的经济效益达259 554.36万元。阔叶树的碳汇能力最强,其次是杉木和马尾松;湖南省的天然林和人工林的碳贮量相差不大,不同龄组碳密度高低排序的基本规律是:过熟林>成熟林>近熟林>中龄林>幼龄林;而中龄林的碳贮量最多,过熟林碳贮量最少。  相似文献   

12.
Tropical forests store a large part of the terrestrial carbon and play a key role in the global carbon (C) cycle. In parts of Southeast Asia, conversion of natural forest to cacao agroforestry systems is an important driver of deforestation, resulting in C losses from biomass and soil to the atmosphere. This case study from Sulawesi, Indonesia, compares natural forest with nearby shaded cacao agroforests for all major above and belowground biomass C pools (n = 6 plots) and net primary production (n = 3 plots). Total biomass (above- and belowground to 250 cm soil depth) in the forest (approx. 150 Mg C ha?1) was more than eight times higher than in the agroforest (19 Mg C ha?1). Total net primary production (NPP, above- and belowground) was larger in the forest than in the agroforest (approx. 29 vs. 20 Mg dry matter (DM) ha?1 year?1), while wood increment was twice as high in the forest (approx. 6 vs. 3 Mg DM ha?1 year?1). The SOC pools to 250 cm depth amounted to 134 and 78 Mg C ha?1 in the forest and agroforest stands, respectively. Replacement of tropical moist forest by cacao agroforest reduces the biomass C pool by approximately 130 Mg C ha?1; another 50 Mg C ha?1 may be released from the soil. Further, the replacement of forest by cacao agroforest also results in a 70–80 % decrease of the annual C sequestration potential due to a significantly smaller stem increment.  相似文献   

13.
Several studies have been conducted in the past on carbon stock measurements in the tropical forests of Indonesia.This study is the first related research conducted in the New Guinea Island.In a degraded logged-over secondary forest in Manokwari Regency (West Papua,Indonesia),carbon stocks were measured for seven parts,i.e.,above-ground biomass (AGB),below-ground biomass (BGB),under-storey biomass (B u),necromass of dead leaves (N l),necromass of dead trees (N t),litter (L) and soil (S) using appropriate equations and laboratory analysis.Total carbon stocks were measured at 642.8 tC·ha-1 in the low disturbance area,536.9 tC·ha-1 in the moderate disturbance area and 490.4 tC·ha-1 in the high disturbance area.B u,N l and N t were not significant in the carbon stock and were collectively categorized as a total biomass complex.The carbon stock of litter was nearly equal to that of the total biomass complex,while the total carbon stock in the soil was eight times larger than the total biomass complex or the carbon stock of the litter.We confirmed that the average ratio of AGB and BGB to the total biomass (TB) was about 84.7% and 15.3%,respectively.Improvements were made to the equations in the low disturbance logged-over secondary forest area,applying corrections to the amounts of biomass of sample trees,based on representative commercial trees of category one.TB stocks before and after correction were estimated to be 84.4 and 106.7 tC·ha-1,indicating that these corrections added significant amounts of tree biomass (26.4%) during the sampling procedure.In conclusion,the equations for tree biomass developed in this study,will be useful for evaluating total carbon stocks,especially TB stocks in logged-over secondary forests throughout the Papua region.  相似文献   

14.
Abstract

The present study was aimed to anticipate how forest composition, regeneration, biomass production, and carbon storage vary in the ridge top forests of the high mountains of Garhwal Himalaya. For this purpose five major forest types—(a) Pinus wallichiana, (b) Quercus semecarpifolia, (c) Cedrus deodara, (d) Abies spectabilis, and (e) Betula utilis mixed forests—were selected on different ridge tops in the Bhagirathi Catchment Area of the Uttarkashi District of Garhwal Himalaya. The highest species richness (10 species) and stand density (804 ± 184.5 stems ha?1) were recorded in Abies spectabilis forests, whereas lowest species richness (4 species) and species density (428 ± 144.7 stems ha?1) were found in Quercus semecarpifolia forests. The total basal cover (TBC) values were maximum (91.1 ± 24.4 m2 ha?1) in Cedrus deodara forests and minimum (26.5 ± 11.7 m2 ha?1) in Pinus wallichiana forests. The highest total biomass density (TBD) (464.2 ± 152.5 Mg ha?1) and total carbon density (TCD; 208.9 ± 68.6 Mg C ha?1) values were recorded for Cedrus deodara forests; however, lowest TBD (283.4 ± 74.8 Mg ha?1) and TCD (127.5 ± 33.7 Mg C ha?1) values for Quercus semecarpifolia forests. Our study suggests that Abies spectabilis-dominated forests should be encouraged for biodiversity enrichment and reducing carbon emissions on ridge top forests of high mountains.  相似文献   

15.
四川省退耕还林碳汇潜力预测研究   总被引:3,自引:0,他引:3  
通过调研四川省退耕还林工程实施现状,建立模型,预测未来60 a 四川省退耕还林工程的碳汇潜力。采用经由森林清查人工林历史生长数据拟合的里查德方程(Richards equation)进行分树种生长量预测,依据文献调研所得有关参数计算相应的生物碳储量,结合碳排放、碳基线和碳泄漏的分析与估算,得出四川省退耕还林工程未来60 a碳汇量。  相似文献   

16.
Temperate and high-latitude forests are carbon sinks and play pivotal roles in offsetting greenhouse gas emissions of CO_2.However,uncertainty still exists for subtropical forests,especially in monsoon-prevalent eastern Asia.Earlier studies have depended on remote sensing,ecosystem modeling,carbon fluxes,or single period forest surveys to estimate carbon sequestration capacities,and the results vary significantly.This study was designed to utilize multi-period forest survey data to explore spatial-dynamics of biomass storage in subtropical forests of China.Jiangxi province,a region with over 60% subtropical forest cover,was selected as the case study site and is located in central east China.Based on forest inventory data 1984-2013,and the stock-difference and biomass expansion factor methods,the carbon storage and density,of arboreal forests,economic forests,bamboo forests,woodlands and shrubberies were estimated.The results show that carbon storage increased from 159.1 Tg C in 1988 to 276.1 TgC in 2013,making up 3.1-3.8% of carbon stored throughout China.Among the four types of forests,the amount of carbon stored was as follows:arboreal forest economic forest bamboo forest woodland and shrubbery.Arboreal forests accounted for 64.0-79.4% of the total.Forest carbon density increased from 21.2 Mg C ha~(-1) in 1984 to26.2 Mg C ha~(-1) in 2013,equal to 61.2-70.2% of the average carbon density of China's forests in the same period.Forest carbon storage in Jiangxi will reach 355.5 Tg C and 535.8 Tg C in 2020 and 2030,respectively,and forest carbon density is predicted to be 31.9 Mg C ha~(~-1)and 46.4 Mg C ha~(-1),respectively.As one of the few studies using multi-period data tracking biomass dynamics in Jiangxi province,the findings of this study may be used as a reference for other research.Using Jiangxi as a case study underlies the fact that subtropical forests in China have great carbon sequestration potential and have fundamental significance to offset global environmental change effects.  相似文献   

17.
Hurricanes cause abrupt carbon reduction in forests, but silviculture treatment can be an effective means of quickly regenerating and restoring hurricane-damaged sites. This study assessed how silviculture treatments affect carbon balance after hurricane damage in central Hokkaido, Japan. We examined carbon storage in trees and underground vegetation as well as carbon emissions from silviculture operations in 25-year-old stands, where scarification and plantation occurred just after hurricane damage. The amount of carbon stored varied according to silviculture treatment. Among three scarification treatments, a scarified depth of 0 cm (understory vegetation removal) led to the largest amount of carbon stored (64.7 t·ha-1 C). Among four plantation treatments, the largest amount of carbon was stored in a Larix hybrid (L. gmelinii var. japonica × L. kaempferi) plantation (80.3 t·ha-1 C). The plantation of Abies sachalinensis was not successful at accumulating carbon (40.5·ha-1 C). The amount of carbon emitted from silviculture operations was 0.05-0.14 t·ha-1 C, and it marginally affected the net carbon balance of the silviculture project. Results indicate that silviculture treatments should beperformed in an appropriate way to effectively recover the ability of carbon sequestration in hurricane-damaged forests.  相似文献   

18.
Forest floor carbon stocks, which include different components of litter, hemic and sapric materials, have not been empirically quantified in tropical montane forest, although they influence soil carbon (C) pools. To date, the contribution of arbuscular mycorrhizae in C sequestration potentials in tropical montane forests have not been clearly investigated. This study determined the amount of C stocks in the different decomposing layers of forest floor, mainly litter, hemic and sapric materials. The abundance of arbuscular mycorrhizal root colonisation differed among forest floor fractions. Forest floor was measured for depth, area density, dry mass and carbon fraction separately in Sungai Kial Forest Reserve, Pahang, Malaysia to calculate C stocks. Percentages of root colonisation in the hemic and sapric materials were investigated. The results showed that forest floor C stocks were significantly higher in hemic (5 Mg C ha?1) and sapric (7.7 Mg C ha?1) compared with the litter fragments (1.5 Mg C ha?1). Mycorrhizal root colonisation was significantly higher (75%) in the toeslope compared with the summit area in the hemic materials. Segregation of forest floor layers provided greater accuracy in forest floor C stocks reporting.  相似文献   

19.
In the context of global carbon cycle management, accurate knowledge of carbon content in forests is a relevant issue in contemporary forest ecology. We measured the above-ground and soil carbon pools in the darkconiferous boreal taiga. We compared measured carbon pools to those calculated from the forest inventory records containing volume stock and species composition data. The inventory data heavily underestimated the pools in the study area(Stolby State Nature Reserve, central Krasnoyarsk Territory, Russian Federation). The carbon pool estimated from the forest inventory data varied from 25(t ha-1)(low-density stands) to 73(t ha-1)(highly stocked stands). Our estimates ranged from 59(t ha-1)(lowdensity stands) to 147(t ha-1)(highly stocked stands). Our values included living trees, standing deadwood, living cover, brushwood and litter. We found that the proportion of biomass carbon(living trees): soil carbon varied from99:1 to 8:2 for fully stocked and low-density forest stands,respectively. This contradicts the common understanding that the biomass in the boreal forests represents only16–20 % of the total carbon pool, with the balance being the soil carbon pool.  相似文献   

20.
相对准确地计量地带性森林碳库大小是估算区域森林碳汇潜力的前提。根据全市不同森林类型设置样地900个,运用样地清查法估算广州市森林生态系统碳储量和碳密度。结果表明:广州市森林生态系统碳储量为52.16 Tg C。其中,植被层和土壤层碳储量分别为21.97 Tg C和27.16 Tg C。碳储量空间分布主要集中在从化区和增城区;总碳储量的组成中,土壤层碳库比例最大(58%),其次为乔木层碳库比例(40%),而灌木层、草本层、凋落物层和细根(≤ 2.0 mm)的生物量比例大多在1%~2%;天然林碳储量与人工林接近,但是碳密度显著大于人工林(p < 0.05);不同林龄从小到大排序为:幼龄林、中龄林、近熟林、过熟林、成熟林;天然林以阔叶混和它软阔的碳储量最高,阔叶混和黎蒴的碳密度最高。人工林不同林型从大到小排序为:南洋楹 > 黎蒴 > 木荷 > 木麻黄 > 它软阔 > 阔叶混 > 湿地松。森林生态系统碳密度为178.03 t C hm-2,其中,植被层和土壤层碳密度分别为79.61 t C hm-2和98.42 t C hm-2。本研究全面计量了广州市森林生态系统碳库现状,这对评估该地区森林固碳潜力和指导碳汇林经营管理具有重要参考价值。  相似文献   

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