WorldWideScience

Sample records for carbon stock influenced

  1. THE Eucalyptus sp. AGE PLANTATIONS INFLUENCING THE CARBON STOCKS

    Directory of Open Access Journals (Sweden)

    Charlote Wink

    2013-06-01

    Full Text Available http://dx.doi.org/10.5902/198050989279The tree growth and biomass accumulation, as well as the maintenance of forest residue at the soil surface can act in the removal of carbon from the atmosphere through the cycling process of plant material. The objective was to study the influence of Eucalyptus sp. Plantations with 20, 44 and 240 months of age on the variation of carbon in soil and biomass. The carbon in the soil depth was determined by CHNS auto-analyzer and carbon in the vegetation was determined by the biomass in each forest, considering a factor of 0.45 of the dry mass. We determined the density and particle size distribution of soil. For the comparison between plantations, there was analysis of variance and comparison of means of carbon in vegetation and soil, considering the 5% level of probability. The carbon content and stock in the soil were low, indicating that a natural feature of the category of Paleuldt, or the growth of eucalyptus forests, replacing the field native vegetation did not aggregate a significant increase in the carbon. Although, there was a significant increase carbon in aboveground biomass. It includes forest biomass and litter. So, despite the values ​​of carbon stocks are low, it identified a greater average total in the soil compared to the stock aboveground. Furthermore, this increase aboveground (tree and litter compartments can be considered significant between the eucalyptus plantations of different ages.

  2. Influence of the Tussock Growth Form on Arctic Ecosystem Carbon Stocks

    Science.gov (United States)

    Curasi, S.; Rocha, A. V.; Sonnentag, O.; Wullschleger, S. D.; Myers-Smith, I. H.; Fetcher, N.; Mack, M. C.; Natali, S.; Loranty, M. M.; Parker, T.

    2015-12-01

    The influence of plant growth forms on ecosystem carbon (C) cycling has been under appreciated. In arctic tundra, environmental factors and plant traits of the sedge Eriophorum vaginatum cause the formation of mounds that are dense amalgamations of belowground C called tussocks. Tussocks have important implications for arctic ecosystem biogeochemistry and C stocks, but the environmental and biological factors controlling their size and distribution across the landscape are poorly understood. In order to better understand how landscape variation in tussock size and density impact ecosystem C stocks, we formed the Carbon in Arctic Tussock Tundra (CATT) network and recruited an international team to sample locations across the arctic. The CATT network provided a latitudinal and longitudinal gradient along which to improve our understanding of tussocks' influence on ecosystem structure and function. CATT data revealed important insights into tussock formation across the arctic. Tussock density generally declined with latitude, and tussock size exhibited substantial variation across sites. The relationship between height and diameter was similar across CATT sites indicating that both biological and environmental factors control tussock formation. At some sites, C in tussocks comprised a substantial percentage of ecosystem C stocks that may be vulnerable to climate change. It is concluded that the loss of this growth form would offset C gains from projected plant functional shifts from graminoid to shrub tundra. This work highlights the role of plant growth forms on the magnitude and retention of ecosystem C stocks.

  3. Soil organic carbon stocks in rangelands of SW Iberian Peninsula as influenced by land degradation

    Science.gov (United States)

    Pulido-Fernández, Manuel; Schnabel, Susanne; Francisco Lavado-Contador, Joaquín

    2014-05-01

    stocking rates ranging from 0.19 to 15.76 LU ha-1. SOC stock was estimated from 48 soil profiles. The study included measurement of a large number of soil properties and degradation indicators, including the assessment of erosion features. The reference soils showed SOC stocks of 71.5 T ha-1, as compared to the 22 grazed units which had an average of 31.1 T ha-1, ranging from 9.7 to 63.6 T ha-1. The units more strongly affected by soil erosion presented lower SOC stocks (26.5 T ha-1) as compared to those presenting few or absence of erosion features (35.1 T ha-1). Remarkable are also the relationships found between SOC stock and other variables such as tree density, soil depth, Ah-horizon thickness and livestock density. Results suggest that soils from dehesas with high tree density store considerable amounts of organic carbon. However excessive stocking rates may lead to land degradation processes, such as water erosion, provoking topsoil losses, where most of SOC is concentrated. Furthermore, the results indicate a complex relationship between SOC and livestock, existing presumably a positive feedback with low to moderate livestock densities and a negative one with high animal density. Further research is necessary to be able to draw definitive conclusions about the influence of domestic animals on carbon stock.

  4. Influence of windthrows and tree species on forest soil plant biomass and carbon stocks

    Science.gov (United States)

    Veselinovic, B.; Hager, H.

    2012-04-01

    The role of forests has generally been recognized in climate change mitigation and adaptation strategies and policies (e.g. Kyoto Protocol within articles 3.3 and 3.4, RES-E Directive of EU, Country Biomass Action Plans etc.). Application of mitigation actions, to decrease of CO2-emissions and, as the increase of carbon(C)-stocks and appropriate GHG-accounting has been hampered due to a lack of reliable data and good statistical models for the factors influencing C-sequestration in and its release from these systems (e.g. natural and human induced disturbances). Highest uncertainties are still present for estimation of soil C-stocks, which is at the same time the second biggest C-reservoir on earth. Spruce monocultures have been a widely used management practice in central Europe during the past century. Such stands are in lower altitudes (e.g. submontane to lower montane elevation zone) and on heavy soils unstable and prone to disturbances, especially on blowdown. As the windthrow-areas act as CO2-source, we hypothesize that conversion to natural beech and oak forests will provide sustainable wood supply and higher stability of stands against blowdown, which simultaneously provides the long-term belowground C-sequestration. This work focuses on influence of Norway spruce, Common beech and Oak stands on belowground C-dynamics (mineral soil, humus and belowground biomass) taking into consideration the increased impact of windthrows on spruce monocultures as a result of climate change. For this purpose the 300-700m altitude and pseudogley (planosols/temporally logged) soils were chosen in order to evaluate long-term impacts of the observed tree species on belowground C-dynamics and human induced disturbances on secondary spruce stands. Using the false chronosequence approach, the C-pools have been estimated for different compartments and age classes. The sampling of forest floor and surface vegetation was done using 30x30 (homogenous plots) and 50x50cm (inhomogeneous

  5. Carbon Stock and Carbon Cycle of Wetland Ecosystem

    OpenAIRE

    Zeng, Zhangquan; Zhang, Canming; LI, JIAO; Yang, Nan; Li, Xiquan; Niu, Yandong; Wu, Zijian

    2014-01-01

    Wetland ecosystem is an essential ecosystem in the world. Its organic carbon stock and carbon cycle are important basis of global carbon cycle researches and also major contents of global climate change researches. Researches have shown that wetland protection and restoration can promote carbon accumulation and reduce emission of greenhouse gases. This paper discussed influence of carbon stock and carbon balance of wetland ecosystem and emission of greenhouse gases, as well as the relationshi...

  6. Carbon Stock and Carbon Cycle of Wetland Ecosystem

    Institute of Scientific and Technical Information of China (English)

    Zhangquan; ZENG; Canming; ZHANG; Jiao; LI; Nan; YANG; Xihao; LI; Yandong; NIU; Zijian; WU

    2014-01-01

    Wetland ecosystem is an essential ecosystem in the world. Its organic carbon stock and carbon cycle are important basis of global carbon cycle researches and also major contents of global climate change researches. Researches have shown that wetland protection and restoration can promote carbon accumulation and reduce emission of greenhouse gases. This paper discussed influence of carbon stock and carbon balance of wetland ecosystem and emission of greenhouse gases,as well as the relationship between wetland and global climate changes. Finally,it made prospect on researches about carbon cycle of Dongting Lake.

  7. Relatively stable carbon stocks in China's grasslands

    Institute of Scientific and Technical Information of China (English)

    FANG ChangMing

    2011-01-01

    Global climate change has been predicted to profoundly influence carbon (C) processes and C stock dynamics in terrestrial ecosystems [1].Three papers recently published in Science China Life Science [2-4] studied various aspects of C stock dynamics at different scales in the northern grasslands of China (including the Tibetan alpine meadow).They reported that there has been no significant trend of variation in ecosystem C stocks in Tibetan meadow and temperate grassland since the late 1980s,or significant correlation between variations in C stocks and warming or precipitation.The response of ecosystem C processes and C stocks to global climate change featuring a significant temperature rise was insignificant.

  8. Biomass Carbon Stock

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Biomass carbon includes carbon stored in above- and below-ground live plant components (such as leaf, branch, stem and root) as well as in standing and down dead...

  9. Soil Organic Carbon Stock

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Soil organic carbon (SOC) is the carbon held within soil organic constituents (i.e., products produced as dead plants and animals decompose and the soil microbial...

  10. Total Ecosystem Carbon Stock

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Total ecosystem carbon includes above- and below-ground live plant components (such as leaf, branch, stem and root), dead biomass (such as standing dead wood, down...

  11. Spatial distribution of soil organic carbon stocks in France

    Directory of Open Access Journals (Sweden)

    M. P. Martin

    2011-05-01

    Full Text Available Soil organic carbon plays a major role in the global carbon budget, and can act as a source or a sink of atmospheric carbon, thereby possibly influencing the course of climate change. Changes in soil organic carbon (SOC stocks are now taken into account in international negotiations regarding climate change. Consequently, developing sampling schemes and models for estimating the spatial distribution of SOC stocks is a priority. The French soil monitoring network has been established on a 16 km × 16 km grid and the first sampling campaign has recently been completed, providing around 2200 measurements of stocks of soil organic carbon, obtained through an in situ composite sampling, uniformly distributed over the French territory.

    We calibrated a boosted regression tree model on the observed stocks, modelling SOC stocks as a function of other variables such as climatic parameters, vegetation net primary productivity, soil properties and land use. The calibrated model was evaluated through cross-validation and eventually used for estimating SOC stocks for mainland France. Two other models were calibrated on forest and agricultural soils separately, in order to assess more precisely the influence of pedo-climatic variables on SOC for such soils.

    The boosted regression tree model showed good predictive ability, and enabled quantification of relationships between SOC stocks and pedo-climatic variables (plus their interactions over the French territory. These relationships strongly depended on the land use, and more specifically, differed between forest soils and cultivated soil. The total estimate of SOC stocks in France was 3.260 ± 0.872 PgC for the first 30 cm. It was compared to another estimate, based on the previously published European soil organic carbon and bulk density maps, of 5.303 PgC. We demonstrate that the present estimate might better represent the actual SOC stock distributions of France, and consequently that the

  12. Spatial distribution of soil organic carbon stocks in France

    Science.gov (United States)

    Martin, M. P.; Wattenbach, M.; Smith, P.; Meersmans, J.; Jolivet, C.; Boulonne, L.; Arrouays, D.

    2011-05-01

    Soil organic carbon plays a major role in the global carbon budget, and can act as a source or a sink of atmospheric carbon, thereby possibly influencing the course of climate change. Changes in soil organic carbon (SOC) stocks are now taken into account in international negotiations regarding climate change. Consequently, developing sampling schemes and models for estimating the spatial distribution of SOC stocks is a priority. The French soil monitoring network has been established on a 16 km × 16 km grid and the first sampling campaign has recently been completed, providing around 2200 measurements of stocks of soil organic carbon, obtained through an in situ composite sampling, uniformly distributed over the French territory. We calibrated a boosted regression tree model on the observed stocks, modelling SOC stocks as a function of other variables such as climatic parameters, vegetation net primary productivity, soil properties and land use. The calibrated model was evaluated through cross-validation and eventually used for estimating SOC stocks for mainland France. Two other models were calibrated on forest and agricultural soils separately, in order to assess more precisely the influence of pedo-climatic variables on SOC for such soils. The boosted regression tree model showed good predictive ability, and enabled quantification of relationships between SOC stocks and pedo-climatic variables (plus their interactions) over the French territory. These relationships strongly depended on the land use, and more specifically, differed between forest soils and cultivated soil. The total estimate of SOC stocks in France was 3.260 ± 0.872 PgC for the first 30 cm. It was compared to another estimate, based on the previously published European soil organic carbon and bulk density maps, of 5.303 PgC. We demonstrate that the present estimate might better represent the actual SOC stock distributions of France, and consequently that the previously published approach at the

  13. Community monitoring of carbon stocks for REDD+

    DEFF Research Database (Denmark)

    Brofeldt, Søren; Theilade, Ida; Burgess, Neil David;

    2014-01-01

    Reducing emissions from deforestation and forest degradation in developing countries, and the role of conservation, sustainable management of forests, and enhancement of forest carbon stocks in developing countries (REDD+) is a potentially powerful international policy mechanism that many tropica...

  14. Ecosystem carbon stock influenced by plantation practice: implications for planting forests as a measure of climate change mitigation.

    Science.gov (United States)

    Liao, Chengzhang; Luo, Yiqi; Fang, Changming; Li, Bo

    2010-01-01

    Uncertainties remain in the potential of forest plantations to sequestrate carbon (C). We synthesized 86 experimental studies with paired-site design, using a meta-analysis approach, to quantify the differences in ecosystem C pools between plantations and their corresponding adjacent primary and secondary forests (natural forests). Totaled ecosystem C stock in plant and soil pools was 284 Mg C ha(-1) in natural forests and decreased by 28% in plantations. In comparison with natural forests, plantations decreased aboveground net primary production, litterfall, and rate of soil respiration by 11, 34, and 32%, respectively. Fine root biomass, soil C concentration, and soil microbial C concentration decreased respectively by 66, 32, and 29% in plantations relative to natural forests. Soil available N, P and K concentrations were lower by 22, 20 and 26%, respectively, in plantations than in natural forests. The general pattern of decreased ecosystem C pools did not change between two different groups in relation to various factors: stand age ( or = 25 years), stand types (broadleaved vs. coniferous and deciduous vs. evergreen), tree species origin (native vs. exotic) of plantations, land-use history (afforestation vs. reforestation) and site preparation for plantations (unburnt vs. burnt), and study regions (tropic vs. temperate). The pattern also held true across geographic regions. Our findings argued against the replacement of natural forests by the plantations as a measure of climate change mitigation. PMID:20523733

  15. Major Factors influences the 2008 Stock Market

    Institute of Scientific and Technical Information of China (English)

    Chun; Yi

    2008-01-01

      2007 was an unusual year for China's stock market, as the index climbed from 2675 points up to 6124 by the end of the year, setting new records again and again throughout 2007. What will happen to the stock market in the coming 2008? Let's havea look at some of the main factors that will influence the stock market this year, perhaps we can find out if 2008 will be another memorable year full of surprises.……

  16. Major Factors influences the 2008 Stock Market

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ 2007 was an unusual year for China's stock market, as the index climbed from 2675 points up to 6124 by the end of the year, setting new records again and again throughout 2007. What will happen to the stock market in the coming 2008? Let's havea look at some of the main factors that will influence the stock market this year, perhaps we can find out if 2008 will be another memorable year full of surprises.

  17. Influence of different tree-harvesting intensities on forest soil carbon stocks in boreal and northern temperate forest ecosystems

    DEFF Research Database (Denmark)

    Clarke, Nicholas; Gundersen, Per; Jönsson-Belyazid, Ulrika; Kjønaas, O. Janne; Persson, Tryggve; Sigurdsson, Bjarni D.; Stupak, Inge; Vesterdal, Lars

    2015-01-01

    ) stocks. This paper reviews the findings in the scientific literature concerning the effects of harvesting of different intensities on SOC stocks and fluxes in boreal and northern temperate forest ecosystems to evaluate the evidence for significant SOC losses following biomass removal. An overview of...... SOC stocks in boreal and northern temperate forest ecosystems, which is in any case species-, site- and practice-specific. Properly conducted long-term experiments are therefore necessary to enable us to clarify the relative importance of different harvesting practices on the SOC stores, the key...

  18. Influence network in Chinese stock market

    CERN Document Server

    Gao, Ya-Chun; Cai, Shi-Min

    2015-01-01

    In a stock market, the price fluctuations are interactive, that is, one listed company can influence others. In this paper, we seek to study the influence relationships among listed companies by constructing a directed network on the basis of Chinese stock market. This influence network shows distinct topological properties, particularly, a few large companies that can lead the tendency of stock market are recognized. Furthermore, by analyzing the subnetworks of listed companies distributed in several significant economic sectors, it is found that the influence relationships are totally different from one economic sector to another, of which three types of connectivity as well as hub-like listed companies are identified. In addition, the rankings of listed companies obtained from the centrality metrics of influence network are compared with that according to the assets, which gives inspiration to uncover and understand the importance of listed companies in the stock market. These empirical results are meaning...

  19. Environmental analyse of soil organic carbon stock changes in Slovakia

    Science.gov (United States)

    Koco, Š.; Barančíková, G.; Skalský, R.; Tarasovičová, Z.; Gutteková, M.; Halas, J.; Makovníková, J.; Novákova, M.

    2012-04-01

    The content and quality of soil organic matter is one of the basic soil parameters on which soil production functioning depends as well as it is active in non production soil functions like an ecological one especially. Morphologic segmentation of Slovakia has significant influence of structure in using agricultural soil in specific areas of our territory. Also social changes of early 90´s of 20´th century made their impact on change of using of agricultural soil (transformation from large farms to smaller ones, decreasing the number of livestock). This research is studying changes of development of soil organic carbon stock (SOC) in agricultural soil of Slovakia as results of climatic as well as social and political changes which influenced agricultury since last 40 years. The main goal of this research is an analysis of soil organic carbon stock since 1970 until now at specific agroclimatic regions of Slovakia and statistic analysis of relation between modelled data of SOC stock and soil quality index value. Changes of SOC stock were evaluated on the basis SOC content modeling using RothC-26.3 model. From modeling of SOC stock results the outcome is that in that time the soil organic carbon stock was growing until middle 90´s years of 20´th century with the highest value in 1994. Since that year until new millennium SOC stock is slightly decreasing. After 2000 has slightly increased SOC stock so far. According to soil management SOC stock development on arable land is similar to overall evolution. In case of grasslands after slight growth of SOC stock since 1990 the stock is in decline. This development is result of transformational changes after 1989 which were specific at decreasing amount of organic carbon input from organic manure at grassland areas especially. At warmer agroclimatic regions where mollic fluvisols and chernozems are present and where are soils with good quality and steady soil organic matter (SOM) the amount of SOC in monitored time is

  20. Influence network in the Chinese stock market

    Science.gov (United States)

    Gao, Ya-Chun; Zeng, Yong; Cai, Shi-Min

    2015-03-01

    In a stock market, the price fluctuations are interactive, that is, one listed company can influence others. In this paper, we seek to study the influence relationships among listed companies by constructing a directed network on the basis of the Chinese stock market. This influence network shows distinct topological properties. In particular, a few large companies that can lead the tendency of the stock market are recognized. Furthermore, by analyzing the subnetworks of listed companies distributed in several significant economic sectors, it is found that the influence relationships are totally different from one economic sector to another, of which three types of connectivity as well as hub-like listed companies are identified. In addition, the rankings of listed companies obtained from the centrality metrics of the influence network are compared with those according to the assets, which gives inspiration to uncover and understand the importance of listed companies on the stock market. These empirical results are meaningful in providing these topological properties of the Chinese stock market and economic sectors as well as revealing the interactive influence relationships among listed companies.

  1. Analysis on the Influence of Stock Index Futures on Chinese Stock Market

    Institute of Scientific and Technical Information of China (English)

    王钊

    2014-01-01

    As the first product of financial futures in China, CSI 300 Stock Index Futures is a symbol of the continual improvement and development of Chinese capital market system. So it would be bound to generate immeasurable influence on Chinese capital market and financial system. Starting from introducing the relevant summaries of stock index futures, this paper analyzes the influence of the stock index futures on the fluctuation in the international stock market;then, it analyzes influence of the stock index futures on the fluctuation in Chinese stock market, in order to propose some suggestions to the policies for developing Chinese stock index futures.

  2. Stocks of organic carbon in Estonian soils

    Directory of Open Access Journals (Sweden)

    Kõlli, Raimo

    2009-06-01

    Full Text Available The soil organic carbon (SOC stocks (Mg ha–1 ofautomorphic mineral (9 soil groups, hydromorphic mineral (7, and lowland organic soils (4 are given for the soil cover or solum layer as a whole and also for its epipedon (topsoil layer. The SOC stocks for forest, arable lands, and grasslands and for the entire Estonian soil cover were calculated on the basis of the mean SOC stock and distribution area of the respective soil type. In the Estonian soil cover (42 400 km2, a total of 593.8 ± 36.9 Tg of SOC is retained, with 64.9% (385.3 ± 27.5 Tg in the epipedon layer (O, H, and A horizons and 35.1% in the subsoil (B and E horizons. The pedo-ecological regularities of SOC retention in soils are analysed against the background of the Estonian soil ordination net.

  3. Influence of soil sampling approaches in the evaluation of soil organic carbon stocks under different land uses in a Mediterranean area

    Science.gov (United States)

    Francaviglia, Rosa; Doro, Luca; Ledda, Luigi; Parras-Alcántara, Luis; Lozano-García, Beatriz

    2016-04-01

    crop (Hc), Pasture (P), Cork oak forest (Cof), former vineyards revegetated by Scrublands (Sfv), Mediterranean Maquis (Mmfv), and Helichrysum meadows (Hmfv). Average total SOCs were 128.0 and 140.6 Mg ha‑1with the ESP and SCS approaches respectively if the coarse fraction is not included in the equation, 79.0 and 90.4 Mg ha‑1when the coarse fraction is included. This indicates the importance to consider the coarse fraction when estimating SOC stocks, and an overestimation of SOCs when SCS sampling approach is adopted equal to about 16%. References Francaviglia, R., Benedetti, A., Doro, L., Madrau, S., Ledda, S., 2014. Influence of land use on soil quality and stratification ratios under agro-silvo-pastoral Mediterranean management systems. Agriculture, Ecosystems and Environment 183, 86-92. Intergovernmental Panel on Climate Change (IPCC), 2003. In: Penman, J., Gytarsky, M., Hiraishi, T., Krug, T., Kruger, D., Pipatti, R., Buendia, L., Miwa, K., Ngara, T., Tanabe, K., Wagner, F. (Eds.), Good Practice Guidance for Land Use, Land Use Change and Forestry. IPCC/OECD/IEA/IGES, Hayama, Japan. IUSS Working Group WRB, 2006.World reference base for soil resources 2006.World Soil Resources Reports No. 103. FAO, Rome. Muñoz-Rojas, M., Doro, L., Ledda, L., Francaviglia, R., 2015. Application of CarboSOIL model to predict the effects of climate change on soil organic carbon stocks in agro-silvo-pastoral Mediterranean management systems. Agriculture, Ecosystems and Environment 202, 8-16. Parras-Alcántara, L., Lozano-García, B., Brevik, E. C., Cerdá, A., 2015a. Soil organic carbon stocks quanti?cation in Mediterranean natural areas, a trade-off between entire soil pro?les and soil control sections. EGU General Assembly. Geophysical Research Abstracts Vol. 17, 2015-9865. Parras-Alcántara, L., Lozano-García, B., Brevik, E., C., Cerdá, A., 2015b. Soil organic carbon stocks assessment in Mediterranean natural areas: A comparison of entire soil profiles and soil control

  4. Soil Organic Carbon Stocks in Depositional Landscapes of Bavaria

    Science.gov (United States)

    Kriegs, Stefanie; Schwindt, Daniel; Völkel, Jörg; Kögel-Knabner, Ingrid

    2016-04-01

    Erosion leads to redistribution and accumulation of soil organic matter (SOM) within agricultural landscapes. These fluvic and colluvic deposits are characterized by a highly diverse vertical structure and can contain high amounts of soil organic carbon (SOC) over the whole soil profile. Depositional landscapes are therefore not only productive sites for agricultural use but also influence carbon dynamics which is of great interest with regard on the recent climate change debate. The aim of our study is to elucidate the spatial distribution of organic carbon stocks, as well as its depth function and the role of these landscapes as a reservoir for SOM. Therefore we compare two representative depositional landscapes in Bavaria composed of different parent materials (carbonate vs. granitic). We hypothesize that the soils associated with different depositional processes (fluvial vs. colluvial) differ in SOC contents and stocks, also because of different hydromorphic regimes in fluvic versus colluvic soil profiles. Sampling sites are located in the Alpine Foreland (quaternary moraines with carbonatic parent material) and the foothills of the Bavarian Forest (Granite with Loess) with the main soil types Fluvisols, Gleysols and Luvisols. At both sites we sampled twelve soil profiles up to 150 cm depth, six in the floodplain and six along a vertical slope transect. We took undisturbed soil samples from each horizon and analyzed them for bulk density, total Carbon (OC and IC) and total Nitrogen (N) concentrations. This approach allows to calculate total OC contents and OC stocks and to investigate vertical and horizontal distribution of OC stocks. It will also reveal differences in OC stocks due to the location of the soil profile in fluvic or colluvic deposition scenarios.

  5. Calculating Organic Carbon Stock from Forest Soils

    Directory of Open Access Journals (Sweden)

    Lucian Constantin DINCĂ

    2015-12-01

    Full Text Available The organic carbon stock (SOC (t/ha was calculated in different approaches in order to enhance the differences among methods and their utility regarding specific studies. Using data obtained in Romania (2000-2012 from 4,500 profiles and 9,523 soil horizons, the organic carbon stock was calculated for the main forest soils (18 types using three different methods: 1 on pedogenetical horizons, by soil bulk density and depth class/horizon thickness; 2 by soil type and standard depths; 3 using regression equations between the quantity of organic C and harvesting depths. Even though the same data were used, the differences between the values of C stock obtained from the three methods were relatively high. The first method led to an overvaluation of the C stock. The differences between methods 1 and 2 were high (and reached 33% for andosol, while the differences between methods 2 and 3 were smaller (a maximum of 23% for rendzic leptosol. The differences between methods 2 and 3 were significantly lower especially for andosol, arenosol and vertisol. A thorough analysis of all three methods concluded that the best method to evaluate the organic C stock was to distribute the obtained values on the following standard depths: 0 - 10 cm; 10 - 20 cm; 20 - 40 cm; > 40 cm. For each soil type, a correlation between the quantity of organic C and the sample harvesting depth was also established. These correlations were significant for all types of soil; however, lower correlation coefficients were registered for rendzic leptosol, haplic podzol and fluvisol.

  6. Soil carbon stocks in Sarawak, Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    Padmanabhan, E., E-mail: Eswaran_padmanabhan@petronas.com.my [Department of Geosciences, Faculty of Geosciences and Petroleum Engineering, Universiti Teknologi PETRONAS, Tronoh, 31750, Perak (Malaysia); Eswaran, H.; Reich, P.F. [USDA-Natural Resources Conservation Service, Washington, DC 20250 (United States)

    2013-11-01

    The relationship between greenhouse gas emission and climate change has led to research to identify and manage the natural sources and sinks of the gases. CO{sub 2}, CH{sub 4}, and N{sub 2}O have an anthropic source and of these CO{sub 2} is the least effective in trapping long wave radiation. Soil carbon sequestration can best be described as a process of removing carbon dioxide from the atmosphere and relocating into soils in a form that is not readily released back into the atmosphere. The purpose of this study is to estimate carbon stocks available under current conditions in Sarawak, Malaysia. SOC estimates are made for a standard depth of 100 cm unless the soil by definition is less than this depth, as in the case of lithic subgroups. Among the mineral soils, Inceptisols tend to generally have the highest carbon contents (about 25 kg m{sup −2} m{sup −1}), while Oxisols and Ultisols rate second (about 10–15 kg m{sup −2} m{sup −1}). The Oxisols store a good amount of carbon because of an appreciable time-frame to sequester carbon and possibly lower decomposition rates for the organic carbon that is found at 1 m depths. Wet soils such as peatlands tend to store significant amounts of carbon. The highest values estimated for such soils are about 114 kg m{sup −2} m{sup −1}. Such appreciable amounts can also be found in the Aquepts. In conclusion, it is pertinent to recognize that degradation of the carbon pool, just like desertification, is a real process and that this irreversible process must be addressed immediately. Therefore, appropriate soil management practices should be instituted to sequester large masses of soil carbon on an annual basis. This knowledge can be used effectively to formulate strategies to prevent forest fires and clearing: two processes that can quickly release sequestered carbon to the atmosphere in an almost irreversible manner. - Highlights: • Soil carbon stocks in different soils in Sarawak • In depth discussion of

  7. Spatial distribution of soil organic carbon stocks in France

    Directory of Open Access Journals (Sweden)

    M. P. Martin

    2010-11-01

    Full Text Available Soil organic carbon plays a major role in the global carbon budget, and can act as a source or a sink of atmospheric carbon, whereby it can influence the course of climate change. Changes in soil organic soil stocks (SOCS are now taken into account in international negotiations regarding climate change. Consequently, developing sampling schemes and models for estimating the spatial distribution of SOCS is a priority. The French soil monitoring network has been established on a 16 km × 16 km grid and the first sampling campaign has recently been completed, providing circa 2200 measurements of stocks of soil organic carbon, obtained through an in situ composite sampling, uniformly distributed over the French territory.

    We calibrated a boosted regression tree model on the observed stocks, modelling SOCS as a function of other variables such as climatic parameters, vegetation net primary productivity, soil properties and land use. The calibrated model was evaluated through cross-validation and eventually used for estimating SOCS for the whole of metropolitan France. Two other models were calibrated on forest and agricultural soils separately, in order to assess more precisely the influence of pedo-climatic variables on soil organic carbon for such soils.

    The boosted regression tree model showed good predictive ability, and enabled quantification of relationships between SOCS and pedo-climatic variables (plus their interactions over the French territory. These relationship strongly depended on the land use, and more specifically differed between forest soils and cultivated soil. The total estimate of SOCS in France was 3.260 ± 0.872 PgC for the first 30 cm. It was compared to another estimate, based on the previously published European soil organic carbon and bulk density maps, of 5.303 PgC. We demonstrate that the present estimate might better represent the actual SOCS distributions of France, and consequently that the previously

  8. Influence of cover crops and crop residue treatment on soil organic carbon stocks evaluated in Swedish long-term field experiments

    Science.gov (United States)

    Poeplau, Christopher; Bolinder, Martin A.; Börjesson, Gunnar; Kätterer, Thomas

    2015-04-01

    Soil organic carbon (SOC) stocks in agricultural soils are strongly controlled by management. In this study we quantified the effect of cover crops and crop residue management on SOC stocks in Swedish long-term experiments. Eight pairs of cover crop (undersown ryegrass) vs. no cover crop were investigated in Swedish long-term field experiments (16 to 24 years). Yields of the main crop were not affected by the cover crop. Cover crops significantly increased SOC stocks, with a mean carbon sequestration rate in all experiments (excluding one) of 0.32±0.29 Mg C ha-1 yr-1. Interestingly, this sequestration is similar to that estimated for a U.S.experiment, where ryegrass growth is much less temperature- and light-limited than under Swedish conditions. This sequestration rate is also the same as that recently reported for many other cover crops in a global meta-analysis but less than SOC changes in ley-dominated rotations which under Nordic conditions were shown to accumulate in average 0.5 Mg C ha-1 yr-1 more carbon compared to exclusively annual cropping systems. Thus, originally introduced in agricultural rotations to reduce nitrate leaching, cover crops are also an effective practice to increase SOC stocks, even at relatively high latitudes. The effect of crop residue treatment was studied in 16 pairs of straw incorporated (SI) vs. straw removed (SR) treatments in six Swedish long-term field experiments. Data series on SOC with 5-28 sampling dates during 27-53 years were analysed using ICBM, a dynamic SOC model. At five out of six sites, the humification coefficient for straw (hlitter; the fraction of straw C that is entering the slow C pool) was much smaller (0-0.09) than the ICBM default h-value for plant material estimated in previous studies (0.125). The derived hlitter-values and thus the stabilization of straw-derived carbon increased significantly with clay content. For an Italian site (with five pairs of SI vs. SR) that was used for model validation we found

  9. Blue carbon stocks in Baltic Sea eelgrass (Zostera marina) meadows

    OpenAIRE

    Röhr, Maria Emilia; Boström, Christoffer; Canal-Vergés, Paula; Holmer, Marianne

    2016-01-01

    Although seagrasses cover only a minor fraction of the ocean seafloor, their carbon sink capacity account for nearly one-fifth of the oceanic carbon burial and thus play a critical structural and functional role in many coastal ecosystems. We sampled 10 eelgrass (Zostera marina) meadows in Finland and 10 in Denmark to explore the seagrass carbon stocks (Corg stock) and the carbon accumulation (Corg accumulation) in the Baltic Sea area. The study sites represent a gradient from sheltered to ex...

  10. Black Carbon Contribution to Organic Carbon Stocks in Urban Soil.

    Science.gov (United States)

    Edmondson, Jill L; Stott, Iain; Potter, Jonathan; Lopez-Capel, Elisa; Manning, David A C; Gaston, Kevin J; Leake, Jonathan R

    2015-07-21

    Soil holds 75% of the total organic carbon (TOC) stock in terrestrial ecosystems. This comprises ecosystem-derived organic carbon (OC) and black carbon (BC), a recalcitrant product of the incomplete combustion of fossil fuels and biomass. Urban topsoils are often enriched in BC from historical emissions of soot and have high TOC concentrations, but the contribution of BC to TOC throughout the urban soil profile, at a regional scale is unknown. We sampled 55 urban soil profiles across the North East of England, a region with a history of coal burning and heavy industry. Through combined elemental and thermogravimetic analyses, we found very large total soil OC stocks (31-65 kg m(-2) to 1 m), exceeding typical values reported for UK woodland soils. BC contributed 28-39% of the TOC stocks, up to 23 kg C m(-2) to 1 m, and was affected by soil texture. The proportional contribution of the BC-rich fraction to TOC increased with soil depth, and was enriched in topsoil under trees when compared to grassland. Our findings establish the importance of urban ecosystems in storing large amounts of OC in soils and that these soils also capture a large proportion of BC particulates emitted within urban areas. PMID:26114917

  11. Community monitoring of carbon stocks for REDD+

    DEFF Research Database (Denmark)

    Brofeldt, Søren; Theilade, Ida; Burgess, Neil David; Danielsen, Finn; Poulsen, Michael K.; Adrian, Teis; Bang, Tran Ngyen; Budiman, Arif; Jensen, Jan; Jensen, Arne E.; Kurniawan, Yuyun; Lægaard, Simon B.L.; Mingxu, Zhao; van Noordwijk, Meine; Rahayu, Subekti; Rutishauser, Ervan; Schmidt-Vogt, Dietrich; Warta, Zulfira; Widayati, Atiek

    2014-01-01

    Reducing emissions from deforestation and forest degradation in developing countries, and the role of conservation, sustainable management of forests, and enhancement of forest carbon stocks in developing countries (REDD+) is a potentially powerful international policy mechanism that many tropical...... countries are working towards implementing. Thus far, limited practical consideration has been paid to local rights to forests and forest resources in REDD+ readiness programs, beyond noting the importance of these issues. Previous studies have shown that community members can reliably and cost......-effectively monitor forest biomass. At the same time, this can improve local ownership and forge important links between monitoring activities and local decision-making. Existing studies have, however, been static assessments of biomass at one point in time. REDD+ programs will require repeated surveys of biomass...

  12. Biomass and Carbon Stocks of Sofala Bay Mangrove Forests

    OpenAIRE

    Almeida A. Sitoe; Luís Júnior Comissário Mandlate; Benard S. Guedes

    2014-01-01

    Mangroves could be key ecosystems in strategies addressing the mitigation of climate changes through carbon storage. However, little is known regarding the carbon stocks of these ecosystems, particularly below-ground. This study was carried out in the mangrove forests of Sofala Bay, Central Mozambique, with the aim of quantifying carbon stocks of live and dead plant and soil components. The methods followed the procedures developed by the Center for International Forestry Research (CIFOR) for...

  13. Ecosystem Carbon Stocks of Intertidal Wetlands in Singapore

    Science.gov (United States)

    Phang, V. X. H.; Friess, D.; Chou, L. M.

    2014-12-01

    Mangrove forests and seagrass meadows provide numerous ecosystem services, with huge recent interest in their carbon sequestration and storage value. Mangrove forests and seagrass meadows as well as mudflats and sandbars form a continuum of intertidal wetlands, but studies that consider these spatially-linked habitats as a whole are limited. This paper presents the results of a field-based and remote sensing carbon stock assessment, including the first study of the ecosystem carbon stocks of these adjacent habitats in the tropics. Aboveground, belowground and soil organic carbon pools were quantified at Chek Jawa, an intertidal wetland in Singapore. Total ecosystem carbon stocks averaged 499 Mg C ha-1 in the mangrove forest and 140 Mg C ha-1 in the seagrass meadow. Soil organic carbon dominated the total storage in both habitats. In the adjacent mudflats and sandbars, soil organic carbon averaged 143 and 124 Mg C ha-1 respectively. High amount of carbon stored in soil demonstrate the role of intertidal wetlands in sequestering large amount of carbon in sediments accumulated over millennia. High-resolution remote sensing imagery was used to create spatial models that upscaled field-based carbon measurements to the national scale. Field-based data and spatial modeling of ecosystem carbon stocks to the entire island through remote sensing provides a large-scale and holistic carbon stock value, important for the understanding and management of these threatened intertidal ecosystems.

  14. TOTAL CARBON STOCK IN AGRICULTURAL SYSTEM HAVING CROP ROTATION IN TARAI REGION OF NORTHERN INDIA

    OpenAIRE

    Kavita Tariyal

    2014-01-01

    Soil organic carbon pools are important in maintaining soil productivity and influencing the CO2 loading into the atmosphere. Agricultural soils can mitigate the problem of carbon concentration increase in atmosphere if proper management practices are involved. In the present study, total carbon stock in crops and soil was analyzed for two years along with crop rotation practice to observe its impact on the carbon pool. For that two agricultural fields C12 and D7 were incorporated with differ...

  15. Digital Mapping of Soil Organic Carbon Contents and Stocks in Denmark

    OpenAIRE

    Kabindra Adhikari; Hartemink, Alfred E.; Budiman Minasny; Rania Bou Kheir; Mette B Greve; Greve, Mogens H.

    2014-01-01

    Estimation of carbon contents and stocks are important for carbon sequestration, greenhouse gas emissions and national carbon balance inventories. For Denmark, we modeled the vertical distribution of soil organic carbon (SOC) and bulk density, and mapped its spatial distribution at five standard soil depth intervals (0-5, 5-15, 15-30, 30-60 and 60-100 cm) using 18 environmental variables as predictors. SOC distribution was influenced by precipitation, land use, soil type, wetland, elevation, ...

  16. Soil carbon stock change following afforestation in Northern Europe

    DEFF Research Database (Denmark)

    Bárcena, Teresa G; Kiær, Lars Pødenphant; Vesterdal, Lars;

    2014-01-01

    Northern Europe supports large soil organic carbon (SOC) pools and has been subjected to high frequency of land-use changes during the past decades. However, this region has not been well represented in previous large-scale syntheses of land-use change effects on SOC, especially regarding effects...... of afforestation. Therefore, we conducted a meta-analysis of SOC stock change following afforestation in Northern Europe. Response ratios were calculated for forest floors and mineral soils (0–10 cm and 0–20/30 cm layers) based on paired control (former land use) and afforested plots. We analyzed the...... influence of forest age, former land-use, forest type, and soil textural class. Three major improvements were incorporated in the meta-analysis: analysis of major interaction groups, evaluation of the influence of nonindependence between samples according to study design, and mass correction. Former land...

  17. Linking soil functions to carbon fluxes and stocks

    Science.gov (United States)

    Olesen, Jørgen E.

    2014-05-01

    Farming practices causing declining returns and inputs of carbon (C) to soils pose threats to sustainable soil functioning by reducing availability of organic matter for soil microbial activities and by affecting soil structure, and soil C stocks that contribute to regulating greenhouse gas emissions. Declines in soil C also affect availability and storage capacity of a range of essential plant nutrients thus affecting needs for external inputs. Soil degradation is considered a serious problem in Europe and a large part of the degradation is caused by agricultural activity with intensive cultivation in arable and mixed farming system contributing to several soil threats. About 45% of European soils are estimated to have low SOM content, principally in southern Europe, but also in areas of France, UK and Germany. The European SOC stocks follow a clear north to south gradient with cooler temperatures favouring higher stocks. However, SOC stocks strongly depend on soil and land management, and there is thus a potential to both increase and lose SOC, although the potential to increase SOC strongly depends on incentives and structures for implementing improved management. Understanding the role of soil C may be better conceptualised by using a soil C flow and stocks concept to assess the impact of C management on crop productivity, soil organic C stocks and other ecosystem services. This concept distinguishes C flows and stocks, which may be hypothesized to have distinctly different effects on biological, chemical and physical soil functions. By separating the roles of carbon flows from the role of carbon stocks, it may become possible to better identify critical levels not only of soil carbon stocks, but also critical levels of carbon inputs, which directly relate to needs for crop and soil management measures. Such critical soil carbon stocks may be linked to soil mineralogy through complexed organic carbon on clay and silt surfaces. Critical levels of soil carbon

  18. THE STUDY OF INFLUENCE ON SUPPLY AND DEMAND OF WOOD AND CARBON STOCK CHANGING WOODEN HOUSE LIFE - CASE STUDY FOR WAKAYAMA PREFECTURE USING GEOGRAPHICAL INFORMATION -

    Science.gov (United States)

    Arikawa, Miho; Taenaka, Sayuri; Tanikawa, Hiroki

    The study evaluated the influence of supply and demand of residential wood on the amounts of carbon fixation and CO2 absorption by forests. The residential wood occupies most of all wood demand. The result of the analysis revealed that both the amounts of carbon fixation in the forest and the residence decreased. Moreover, it was clarified that the wood utilization for long-lived houses made the amounts of carbon fixation in the forests and residences the maximum. On the other hand, the amounts of CO2 absorption by the man-made forest would decrease in the future. However, the study showed the possibility of the increase in CO2 absorption admitted in the Kyoto Protocol.

  19. Does Stock Market Performance Influence Retirement Intentions?

    OpenAIRE

    Gopi Shah Goda; John B. Shoven; Sita Nataraj Slavov

    2012-01-01

    Media reports predicted that the stock market decline in October 2008 would cause changes in retirement intentions, due to declines in retirement assets. We use panel data from the Health and Retirement Study to investigate the relationship between stock market performance and retirement intentions during 1998-2008, a period that includes the recent crisis. While we find a weak negative correlation between stock returns and retirement intentions, further investigation suggests that this relat...

  20. Benchmark values for forest soil carbon stocks in Europe

    DEFF Research Database (Denmark)

    De Vos, Bruno; Cools, Nathalie; Ilvesniemi, Hannu;

    2015-01-01

    Soil organic carbon (SOC) stocks in forest floors and in mineral and peat forest soils were estimated at the European scale. The assessment was based on measured C concentration, bulk density, coarse fragments and effective soil depth data originating from 4914 plots in 22 EU countries belonging to...... the UN/ECE ICP Forests 16 × 16 km Level I network. Plots were sampled and analysed according to harmonized methods during the 2nd European Forest Soil Condition Survey. Using continuous carbon density depth functions, we estimated SOC stocks to 30-cm and 1-m depth, and stratified these stocks...... according to 22 WRB Reference Soil Groups (RSGs) and 8 humus forms to provide European scale benchmark values. Average SOC stocks amounted to 22.1 t C ha− 1 in forest floors, 108 t C ha− 1 in mineral soils and 578 t C ha− 1 in peat soils, to 1 m depth. Relative to 1-m stocks, the vertical SOC distribution...

  1. Does Stock Market Performance Influence Retirement Intentions?

    Science.gov (United States)

    Goda, Gopi Shah; Shoven, John B.; Slavov, Sita Nataraj

    2012-01-01

    Media reports predicted that the stock market decline in October 2008 would cause changes in retirement intentions, due to declines in retirement assets. We use panel data from the Health and Retirement Study to investigate the relationship between stock market performance and retirement intentions during 1998-2008, a period that includes the…

  2. What are the effects of agricultural management on soil organic carbon (SOC) stocks?

    DEFF Research Database (Denmark)

    Söderström, Bo; Hedlund, Katarina; Jackson, Louise E.;

    2014-01-01

    Changes in soil organic carbon (SOC) stocks significantly influence the atmospheric C concentration. Agricultural management practices that increase SOC stocks thus may have profound effects on climate mitigation. Additional benefits include higher soil fertility since increased SOC stocks improve...... the physical and biological properties of the soil. Intensification of agriculture and land-use change from grasslands to croplands are generally known to deplete SOC stocks. The depletion is exacerbated through agricultural practices with low return of organic material and various mechanisms, such as...... oxidation/mineralization, leaching and erosion. However, a systematic review comparing the efficacy of different agricultural management practices to increase SOC stocks has not yet been produced. Since there are diverging views on this matter, a systematic review would be timely for framing policies not...

  3. Ecosystem-Level Carbon Stocks in Costa Rican Mangrove Forests

    Science.gov (United States)

    Cifuentes, M.

    2012-12-01

    Tropical mangroves provide a wide variety of ecosystem services, including atmospheric carbon sequestration. Because of their high rates of carbon accumulation, the large expected size of their total stocks (from 2 to 5 times greater than those of upland tropical forests), and the alarming rates at which they are being converted to other uses (releasing globally from 0.02 to 0.12 Pg C yr-1), mangroves are receiving increasing attention as additional tools to mitigate climate change. However, data on whole ecosystem-level carbon in tropical mangroves is limited. Here I present the first estimate of ecosystem level carbon stocks in mangrove forests of Central America. I established 28, 125 m-long, sampling transects along the 4 main rivers draining the Térraba-Sierpe National Wetland in the southern Pacific coast of Costa Rica. This area represents 39% of all remaining mangroves in the country (48300 ha). A circular nested plot was placed every 25 m along each transect. Carbon stocks of standing trees, regeneration, the herbaceous layer, litter, and downed wood were measured following internationally-developed methods compatible with IPCC "Good Practice Guidelines". In addition, total soil carbon stocks were determined down to 1 m depth. Together, these carbon estimates represent the ecosystem-carbon stocks of these forests. The average aboveground carbon stocks were 72.5 ± 3.2 MgC ha-1 (range: 9 - 241 MgC ha-1), consistent with results elsewhere in the world. Between 74 and 92% of the aboveground carbon is stored in trees ≥ 5cm dbh. I found a significant correlation between basal area of trees ≥ 5cm dbh and total aboveground carbon. Soil carbon stocks to 1 m depth ranged between 141 y 593 MgC ha-1. Ecosystem-level carbon stocks ranged from 391 MgC ha-1 to 438 MgC ha-1, with a slight increase from south to north locations. Soil carbon stocks represent an average 76% of total ecosystem carbon stocks, while trees represent only 20%. These Costa Rican mangroves

  4. Effects of Deforestation and Forest Degradation on Forest Carbon Stocks in Collaborative Forests, Nepal

    Directory of Open Access Journals (Sweden)

    Ram Asheshwar MANDAL

    2012-12-01

    Full Text Available There are some key drivers that favor deforestation and forest degradation. Consequently, levels of carbon stock are affected in different parts of same forest types. But the problem lies in exploring the extent of the effects on level of carbon stocking. This paper highlights the variations in levels of carbon stocks in three different collaborative forests of same forest type i.e. tropical sal (Shorea robusta forest in Mahottari district of the central Terai in Nepal. Three collaborative forests namely Gadhanta-Bardibas Collaborative Forest (CFM, Tuteshwarnath CFM and Banke- Maraha CFM were selected for research site. Interview and workshops were organized with the key informants that include staffs, members and representatives of CFMs to collect the socio-economic data and stratified random sampling was applied to collect the bio-physical data to calculate the carbon stocks. Analysis was carried out using statistical tools. It was found five major drivers namely grazing, fire, logging, growth of invasive species and encroachment. It was found highest carbon 269.36 ton per ha in Gadhanta- Bardibash CFM. The findings showed that the levels of carbon stocks in the three studied CFMs are different depending on how the drivers of deforestation and forest degradation influence over them.

  5. Carbon stock of seagrass community in Barranglompo Island Makassar

    OpenAIRE

    Supriadi,Supriadi; Kaswadji, Richardus F; Bengen, Dietrich G; Hutomo, Malikusworo

    2014-01-01

    Blue carbon concept as introduced by UNEP, FAO and UNESCO in 2009 included seagrass beds as one ecosystem having a significant role in global carbon absorption. Absorbed carbon was stored and distributed in various compartments such as in sediments, herbivores, water column, other ecosystems and in form of biomass. The research was conducted in Barranglompo Island, Makassar City to analyze the potency of carbon stock that stored within seagrass biomass. Seagrass density was sampled using quad...

  6. TOTAL CARBON STOCK IN AGRICULTURAL SYSTEM HAVING CROP ROTATION IN TARAI REGION OF NORTHERN INDIA

    Directory of Open Access Journals (Sweden)

    Kavita Tariyal

    2014-06-01

    Full Text Available Soil organic carbon pools are important in maintaining soil productivity and influencing the CO2 loading into the atmosphere. Agricultural soils can mitigate the problem of carbon concentration increase in atmosphere if proper management practices are involved. In the present study, total carbon stock in crops and soil was analyzed for two years along with crop rotation practice to observe its impact on the carbon pool. For that two agricultural fields C12 and D7 were incorporated with different crop rotations for two years and on the basis of this SOC, Total Carbon, soil respiration and carbon stock were measured. In the end of the study C12 showed higher biomass carbon stock (2.61 t ha-1 as compared to D7 (1.98 t ha-1 and also higher total carbon stock (plant+soil (40.09 t ha-1 as compared to D7 (38.30 t ha-1. Results prove that agriculture can not only be the source but also an effective sink if it is properly managed with different crop rotation practices and also with no-till practice.

  7. Predators help protect carbon stocks in blue carbon ecosystems

    Science.gov (United States)

    Atwood, Trisha B.; Connolly, Rod M.; Ritchie, Euan G.; Lovelock, Catherine E.; Heithaus, Michael R.; Hays, Graeme C.; Fourqurean, James W.; Macreadie, Peter I.

    2015-12-01

    Predators continue to be harvested unsustainably throughout most of the Earth's ecosystems. Recent research demonstrates that the functional loss of predators could have far-reaching consequences on carbon cycling and, by implication, our ability to ameliorate climate change impacts. Yet the influence of predators on carbon accumulation and preservation in vegetated coastal habitats (that is, salt marshes, seagrass meadows and mangroves) is poorly understood, despite these being some of the Earth's most vulnerable and carbon-rich ecosystems. Here we discuss potential pathways by which trophic downgrading affects carbon capture, accumulation and preservation in vegetated coastal habitats. We identify an urgent need for further research on the influence of predators on carbon cycling in vegetated coastal habitats, and ultimately the role that these systems play in climate change mitigation. There is, however, sufficient evidence to suggest that intact predator populations are critical to maintaining or growing reserves of 'blue carbon' (carbon stored in coastal or marine ecosystems), and policy and management need to be improved to reflect these realities.

  8. Organic carbon concentrations and stocks in Romanian mineral forest soils

    OpenAIRE

    Lucian C. Dincă; Gheorghe Spârchez; Maria Dincă; Viorel N. B. Blujdea

    2012-01-01

    Estimating soils organic carbon stock and its change in time is an actual concern for scientists and climate change policy makers. The present article firstly focus on determination of C stocks in Romania on forest soil types, as well as development of the spatial distribution mapping using a Geographic Information System (GIS) and also the secondly on the quantification of uncertainty associated with currently available data on C concentration on forest soils geometrical layers. Determinatio...

  9. Temporal Assessment of Growing Stock, Biomass and Carbon Stock of Indian Forests

    Energy Technology Data Exchange (ETDEWEB)

    Manhas, R.K.; Negi, J.D.S.; Chauhan, P.S. [Forest Ecology and Environment Division, Forest Research Institute, Dehradun, 248 006, Uttaranchal (India); Kumar, R. [Forest Survey of India, Dehradun, 248 001, Uttaranchal (India)

    2006-01-15

    The dynamics of terrestrial ecosystems depends on interactions between carbon, nutrient and hydrological cycles. Terrestrial ecosystems retain carbon in live biomass (aboveground and belowground), decomposing organic matter, and soil. Carbon is exchanged naturally between these systems and the atmosphere through photosynthesis, respiration, decomposition, and combustion. Human activities change carbon stock in these pools and exchanges between them and the atmosphere through land-use, land-use change, and forestry. In the present study we estimated the wood (stem) biomass, growing stock (GS) and carbon stock of Indian forests for 1984 and 1994. The forest area, wood biomass, GS, and carbon stock were 63.86 Mha, 4327.99 Mm{sup 3}, 2398.19 Mt and 1085.06 Mt respectively in 1984 and with the reduction in forest area, 63.34 Mha, in 1994, wood biomass (2395.12 Mt) and carbon stock (1083.69 Mt) also reduced subsequently. The Conifers, of temperate region, stocked maximum carbon in their woods, 28.88 to 65.21 t C/ha, followed by Mangrove forests, 28.24 t C/ha, Dipterocarp forests, 28.00 t C/ha, and Shorea robusta forests, 24.07 t C/ha. Boswellia serrata, with 0.22 Mha forest area, stocked only 3.91 t C/ha. To have an idea of rate of carbon loss the negative changes (loss of forest area) in forest area occurred during 1984-1994 (10yrs) and 1991-1994 (4yrs) were also estimated. In India, land-use changes and fuelwood requirements are the main cause of negative change. Total 24.75 Mt C was lost during 1984-1994 and 21.35 Mt C during 1991-94 at a rate of 2.48 Mt C/yr and 5.35 Mt C/yr respectively. While in other parts of India negative change is due to multiple reasons like fuelwood, extraction of non-wood forest products (NWFPs), illicit felling etc., but in the northeastern region of the country shifting cultivation is the only reason for deforestation. Decrease in forest area due to shifting cultivation accounts for 23.0% of the total deforestation in India, with an annual

  10. Deadwood biomass: an underestimated carbon stock in degraded tropical forests?

    Science.gov (United States)

    Pfeifer, Marion; Lefebvre, Veronique; Turner, Edgar; Cusack, Jeremy; Khoo, MinSheng; Chey, Vun K.; Peni, Maria; Ewers, Robert M.

    2015-04-01

    Despite a large increase in the area of selectively logged tropical forest worldwide, the carbon stored in deadwood across a tropical forest degradation gradient at the landscape scale remains poorly documented. Many carbon stock studies have either focused exclusively on live standing biomass or have been carried out in primary forests that are unaffected by logging, despite the fact that coarse woody debris (deadwood with ≥10 cm diameter) can contain significant portions of a forest’s carbon stock. We used a field-based assessment to quantify how the relative contribution of deadwood to total above-ground carbon stock changes across a disturbance gradient, from unlogged old-growth forest to severely degraded twice-logged forest, to oil palm plantation. We measured in 193 vegetation plots (25 × 25 m), equating to a survey area of >12 ha of tropical humid forest located within the Stability of Altered Forest Ecosystems Project area, in Sabah, Malaysia. Our results indicate that significant amounts of carbon are stored in deadwood across forest stands. Live tree carbon storage decreased exponentially with increasing forest degradation 7-10 years after logging while deadwood accounted for >50% of above-ground carbon stocks in salvage-logged forest stands, more than twice the proportion commonly assumed in the literature. This carbon will be released as decomposition proceeds. Given the high rates of deforestation and degradation presently occurring in Southeast Asia, our findings have important implications for the calculation of current carbon stocks and sources as a result of human-modification of tropical forests. Assuming similar patterns are prevalent throughout the tropics, our data may indicate a significant global challenge to calculating global carbon fluxes, as selectively-logged forests now represent more than one third of all standing tropical humid forests worldwide.

  11. Modeling the uncertainty of estimating forest carbon stocks in China

    Science.gov (United States)

    Yue, T. X.; Wang, Y. F.; Du, Z. P.; Zhao, M. W.; Zhang, L. L.; Zhao, N.; Lu, M.; Larocque, G. R.; Wilson, J. P.

    2015-12-01

    Earth surface systems are controlled by a combination of global and local factors, which cannot be understood without accounting for both the local and global components. The system dynamics cannot be recovered from the global or local controls alone. Ground forest inventory is able to accurately estimate forest carbon stocks at sample plots, but these sample plots are too sparse to support the spatial simulation of carbon stocks with required accuracy. Satellite observation is an important source of global information for the simulation of carbon stocks. Satellite remote-sensing can supply spatially continuous information about the surface of forest carbon stocks, which is impossible from ground-based investigations, but their description has considerable uncertainty. In this paper, we validated the Lund-Potsdam-Jena dynamic global vegetation model (LPJ), the Kriging method for spatial interpolation of ground sample plots and a satellite-observation-based approach as well as an approach for fusing the ground sample plots with satellite observations and an assimilation method for incorporating the ground sample plots into LPJ. The validation results indicated that both the data fusion and data assimilation approaches reduced the uncertainty of estimating carbon stocks. The data fusion had the lowest uncertainty by using an existing method for high accuracy surface modeling to fuse the ground sample plots with the satellite observations (HASM-SOA). The estimates produced with HASM-SOA were 26.1 and 28.4 % more accurate than the satellite-based approach and spatial interpolation of the sample plots, respectively. Forest carbon stocks of 7.08 Pg were estimated for China during the period from 2004 to 2008, an increase of 2.24 Pg from 1984 to 2008, using the preferred HASM-SOA method.

  12. Analysing the uncertainty of estimating forest carbon stocks in China

    Science.gov (United States)

    Yue, Tian Xiang; Wang, Yi Fu; Du, Zheng Ping; Zhao, Ming Wei; Li Zhang, Li; Zhao, Na; Lu, Ming; Larocque, Guy R.; Wilson, John P.

    2016-07-01

    Earth surface systems are controlled by a combination of global and local factors, which cannot be understood without accounting for both the local and global components. The system dynamics cannot be recovered from the global or local controls alone. Ground forest inventory is able to accurately estimate forest carbon stocks in sample plots, but these sample plots are too sparse to support the spatial simulation of carbon stocks with required accuracy. Satellite observation is an important source of global information for the simulation of carbon stocks. Satellite remote sensing can supply spatially continuous information about the surface of forest carbon stocks, which is impossible from ground-based investigations, but their description has considerable uncertainty. In this paper, we validated the Kriging method for spatial interpolation of ground sample plots and a satellite-observation-based approach as well as an approach for fusing the ground sample plots with satellite observations. The validation results indicated that the data fusion approach reduced the uncertainty of estimating carbon stocks. The data fusion had the lowest uncertainty by using an existing method for high-accuracy surface modelling to fuse the ground sample plots with the satellite observations (HASM-S). The estimates produced with HASM-S were 26.1 and 28.4 % more accurate than the satellite-based approach and spatial interpolation of the sample plots respectively. Forest carbon stocks of 7.08 Pg were estimated for China during the period from 2004 to 2008, an increase of 2.24 Pg from 1984 to 2008, using the preferred HASM-S method.

  13. Northern peatland carbon stocks and dynamics: a review

    Directory of Open Access Journals (Sweden)

    Z. C. Yu

    2012-10-01

    Full Text Available Peatlands contain a large belowground carbon (C stock in the biosphere, and their dynamics have important implications for the global carbon cycle. However, there are still large uncertainties in C stock estimates and poor understanding of C dynamics across timescales. Here I review different approaches and associated uncertainties of C stock estimates in the literature, and on the basis of the literature review my best estimate of C stocks and uncertainty is 500 ± 100 (approximate range gigatons of C (Gt C in northern peatlands. The greatest source of uncertainty for all the approaches is the lack or insufficient representation of data, including depth, bulk density and carbon accumulation data, especially from the world's large peatlands. Several ways to improve estimates of peat carbon stocks are also discussed in this paper, including the estimates of C stocks by regions and further utilizations of widely available basal peat ages.

    Changes in peatland carbon stocks over time, estimated using Sphagnum (peat moss spore data and down-core peat accumulation records, show different patterns during the Holocene, and I argue that spore-based approach underestimates the abundance of peatlands in their early histories. Considering long-term peat decomposition using peat accumulation data allows estimates of net carbon sequestration rates by peatlands, or net (ecosystem carbon balance (NECB, which indicates more than half of peat carbon (> 270 Gt C was sequestrated before 7000 yr ago during the Holocene. Contemporary carbon flux studies at 5 peatland sites show much larger NECB during the last decade (32 ± 7.8 (S.E. g C m−2 yr–1 than during the last 7000 yr (∼ 11 g C m−2 yr–1, as modeled from peat records across northern peatlands. This discrepancy highlights the urgent need for carbon accumulation data and process understanding, especially at decadal and centennial timescales

  14. Factors Influencing the Zimbabwe Stock Exchange Performance (2002-2007)

    OpenAIRE

    Kosmas Njanike; Pension Katsuro; Michael Mudzura

    2009-01-01

    This paper assesses the factors that influenced the Zimbabwe Stock Exchange’s performance from 2002 to 2007. The study seeks to identify and define the major drivers of the bourse during this period and use them to guide an investor on the ZSE or any other stock exchange in a developing economy. Despite the shrinking of the economy since 2000, the stock market inversely reacted to the factors that affected the economy negatively. The ZSE was driven mainly by speculation as investors sought to...

  15. Carbon Stocks in Harran Plain Soils, Sanliurfa, Turkey

    Directory of Open Access Journals (Sweden)

    Erdal SAKIN

    2010-12-01

    Full Text Available Soils are an important component of the global carbon cycle and can be net sources or sinks of atmospheric carbon dioxide (CO2. The goals of the present study were to analyze the soil organic carbon (SOC and soil inorganic carbon (SIC content of Harran Plain soil in Sanliurfa, Turkey, part of the Southeast Anatolia region (SAR, and to estimate carbon stocks (CSs in soil series that are representative of arid and semiarid lands. To this end, soil samples were collected from 16 profiles in the Harran Plain at depths of 100, 120, and 160 cm of the genetic horizons, and the SOC stocks in the three soil depths were estimated. The carbon stock was 56.41 Tg of C in the 0-100 cm layer, 67.80 Tg of C in the 0-120 cm layer and 87.91 Tg of C in the 0-160 cm layer. For the three soil depths 100, 120, and 160 cm, the SOC content ranged from 6.33 to 11.04, 7.11 to 11.98 and 8.72 to 16.53 kg of C m-2, respectively, and the soil inorganic carbon content ranged from 8.83 to 19.26, 11.00 to 23.34 and 14.82 to 32.64 kg of C m-2, respectively.

  16. Carbon stocks in Portuguese maritime pine stands

    OpenAIRE

    Nunes, Luís; Patrício, Maria do Sameiro; Tomé, José; Tomé, Margarida

    2010-01-01

    One of the Pan-European Criteria for the Sustainable Forest Management is the Maintenance and Appropriate Enhancement of Forest Resources and their Contribution to Global Carbon Cycles. Carbon dioxide (CO2) is the most important anthropogenic greenhouse gas. Its annual emissions increased by about 80% between 1970 and 2004 according to the 2007 report from IPCC, being the main responsible for the changes in the world climate. Today, the carbon sequestration is among the most important service...

  17. Biodiversity, carbon stocks and community monitoring in traditional agroforestry practices

    DEFF Research Database (Denmark)

    Hartoyo, Adisti Permatasari Putri; Siregar, Iskandar Z.; Supriyanto;

    2016-01-01

    Traditional agroforestry practices in Berau, East Kalimantan, are suitable land use types to conserve that potentially support the implementation of REDD+. The objectives of this research are to assess biodiversity and carbon stock in various traditional agroforestry practices, also to determine ...

  18. Climate change mitigation by carbon stocking

    DEFF Research Database (Denmark)

    Lykke, Anne Mette; Barfod, Anders S.; Svendsen, Gert Tinggaard;

    2009-01-01

    Semi-arid West Africa has not been integrated into the afforestation/reforestation (AR) carbon market. Most projects implemented under the Clean Development Mechanism (CDM) have focused on carbon emission reductions from industry and energy consumption, whereas only few (only one in West Africa) ...

  19. How accurately can soil organic carbon stocks and stock changes be quantified by soil inventories?

    Directory of Open Access Journals (Sweden)

    M. Schrumpf

    2011-05-01

    Full Text Available Precise determination of changes in organic carbon (OC stocks is prerequisite to understand the role of soils in the global cycling of carbon and to verify changes in stocks due to management. A large dataset was collected to form base to repeated soil inventories at 12 CarboEurope sites under different climate and land-use, and with different soil types. Concentration of OC, bulk density (BD, and fine earth fraction were determined to 60 cm depth at 100 sampling points per site. We investigated (1 time needed to detect changes in soil OC, assuming future re-sampling of 100 cores; (2 the contribution of different sources of uncertainties to OC stocks; (3 the effect of OC stock calculation on mass rather than volume base for change detection; and (4 the potential use of pedotransfer functions (PTF for estimating BD in repeated inventories.

    The period of time needed for soil OC stocks to change strongly enough to be detectable depends on the spatial variability of soil properties, the depth increment considered, and the rate of change. Cropland sites, having small spatial variability, had lower minimum detectable differences (MDD with 100 sampling points (105 ± 28 gC m−2 for the upper 10 cm of the soil than grassland and forest sites (206 ± 64 and 246 ± 64 gC m−2 for 0–10 cm, respectively. Expected general trends in soil OC indicate that changes could be detectable after 2–15 yr with 100 samples if changes occurred in the upper 10 cm of stone-poor soils. Error propagation analyses showed that in undisturbed soils with low stone contents, OC concentrations contributed most to OC stock variability while BD and fine earth fraction were more important in upper soil layers of croplands and in stone rich soils. Though the calculation of OC stocks based on equivalent soil masses slightly decreases the chance to detect changes with time at most sites except for the croplands, it is still recommended to

  20. How accurately can soil organic carbon stocks and stock changes be quantified by soil inventories?

    Directory of Open Access Journals (Sweden)

    M. Schrumpf

    2011-01-01

    Full Text Available Precise determination of changes in organic carbon (OC stocks is prerequisite to understand the role of soils in the global cycling of carbon and to verify changes in stocks due to management. A large dataset was collected to form base to repeated soil inventories at 12 CarboEurope sites under different climate and land-use, and with different soil types. Concentration of OC, bulk density (BD, and fine earth fraction were determined to 60 cm depth at 100 sampling points per site. We investigated (1 time needed to detect changes in soil OC, assuming future re-sampling of 100 cores; (2 the contribution of different sources of uncertainties to OC stocks; (3 the effect of OC stock calculation on mass rather than volume base for change detection; and (4 the potential use of pedotransfer functions (PTF for estimating BD in repeated inventories.

    The period of time needed for soil OC stocks to change strongly enough to be detectable depends on the spatial variability of soil properties, the depth increment considered, and the rate of change. Cropland sites, having small spatial variability, had lower minimum detectable differences (MDD with 100 sampling points (105 ± 28 kg C m−2 for the upper 10 cm of the soil than the grassland (206 ± 64 kg C m−2 and forest (246 ± 64 kg C m−2 sites. Expected general trends in soil OC indicate that changes could be detectable after 2–15 years with 100 samples if changes occurred in the upper 10 cm of stone-poor soils. Error propagation analyses showed that in undisturbed soils with low stone contents, OC concentrations contributed most to OC stock variability while BD and fine earth fraction were more important in upper soil layers of croplands and in stone rich soils. Though the calculation of OC stocks based on equivalent soil masses slightly decreases the chance to detect changes with time at most sites except for the croplands, it is still recommended to account

  1. Northern peatland carbon stocks and dynamics: a review

    Directory of Open Access Journals (Sweden)

    Z. Yu

    2012-04-01

    Full Text Available Here I review different approaches and associated uncertainties of estimates in the literature of carbon stocks and found that there is most likely 500 (± 100 range gigatons of carbon (Gt C in northern peatlands. The greatest uncertainty for all the approaches is the lack or insufficient representation of data, including depth, bulk density and carbon accumulation data, especially from the world's large peatlands. Several ways to improve estimates of peat carbon stocks were also discussed in this paper. Changes in peatland carbon stocks over time, estimated using Sphagnum (peat moss spore data and down-core peat accumulation records, show different patterns during the Holocene. Considering long-term peat decomposition using peat accumulation data allows estimates of net carbon sequestration rates by peatlands, or net ecosystem carbon balance (NECB, which indicates more than half of peat carbon (> 270 Gt C was sequestrated before 7000 yr ago during the Holocene. Contemporary carbon flux studies at 5 peatland sites show much larger NECB during the last decade (32 ± 7.8 (S.E. g C m−2 yr−1 than during the last 7000 yr (~ 11 g C m−2 yr−1 as modeled from peat records across northern peatlands. This discrepancy highlights the urgent need for carbon accumulation data and process understanding, especially at decadal and centennial timescales, that would bridge current knowledge gaps and facilitate comparisons of NECB across all timescales.

  2. Drivers of organic carbon stock of agricultural soils in eastern Australia

    Science.gov (United States)

    Rabbi, Sheikh M. F.; Tighe, Matthew; Delgado-Baquerizo, Manuel; Cowie, Annette; Robertson, Fiona; Dalal, Ram; Page, Kathryn; Crawford, Doug; Wilson, Brian; Schwenke, Graeme; Mcleod, Malem; Badgery, Warwick; Dang, Yash; Bell, Mike; Baldock, Jeff

    2015-04-01

    Assessing the factors that control carbon storage is the key to formulating conservation policies and sustainable soil management under changing environments. Here, we evaluate the major drivers of soil organic carbon storage in eastern Australia. To do this, we used a regional dataset including 1482 sites and targeting key land uses and soil management practices on major soils of New South Wales (NSW), Queensland (QLD) and Victoria (VIC). Structural equation modeling (SEM) and conditional inference tree (CTREE) analyses were performed to evaluate the relative importance of climate, topography, soil properties, land use and soil management practices on soil organic carbon stocks in 0-30 cm. The results showed that aridity, the most important factor controlling carbon storage, had a strong negative (r = -0.82, pstock. Only a small portion (stock could be explained by land use. The results of CTREE analysis showed that pastures, and pasture dominant crop-pasture rotations had positive influence on soil carbon stocks. The CTREE results also indicated that aridity regulates the amount of carbon present in the soil under different land uses. Using a novel multivariate technique the current work identified that aridity and clay content of soil are the main drivers of carbon storage at a regional scale over others factors such as land uses and soil management practices.

  3. Carbon Stocks and Sequestration: How much do we know?

    Science.gov (United States)

    Mathabane, N.; Kelsey, K.; Neff, J. C.

    2012-12-01

    As anthropogenic CO¬¬2 emissions in America increase, both Washington D.C. and state governments look for ways to offset those carbon increases. Our forests provide an opportunity for carbon sequestration, assuming well-informed and deliberate management practices. Accurate spatial and temporal estimates of carbon stocks are integral to developing wise management practices. Spatial carbon stock estimates are often represented in carbon maps while temporal estimates are calculated using computer models. These maps and models come from a variety of sources such as the United States Department of Agriculture (USDA), the Forest Service (FS), and independent researchers. Here we evaluate the Forest Service's Forest Vegetation Simulator (FVS) to determine its sensitivity to input changes as well as its predictive ability over time. We analyze field data collected from a site in the San Juan National Forest. This site was clearcut in 1920, allowing us to model a complete regrowth over 90 years. Using biomass-to-carbon equations, we compare present-day carbon storage to FVS model projections. Finally, we look at the Forest Inventory and Analysis (FIA) database and a spatial carbon map developed by researchers at the University of Colorado to assess the validity of landscape-scale estimates. Results indicate that the four spatial carbon estimates we use vary by only 25% while the temporal carbon estimates diverge radically from field data. Knowledge of carbon uptake rates is one of the most pressing questions in atmospheric and ecological science. It is imperative that carbon models be improved to achieve this goal. Spatial and temporal comparisons such as the one conducted here are needed to provide the groundwork for model development. Carbon estimates for Shearer Creek in the San Juan National Forest based on four different methods: the Forest Vegetation Simulator, the USDA Forest Inventory and Analysis Database, a spatial carbon map from the University of Colorado

  4. Spatial optimization of carbon-stocking projects across Africa integrating stocking potential with co-benefits and feasibility

    Science.gov (United States)

    Greve, Michelle; Reyers, Belinda; Mette Lykke, Anne; Svenning, Jens-Christian

    2013-12-01

    Carbon offset projects through forestation are employed within the emissions trading framework to store carbon. Yet, information about the potential of landscapes to stock carbon, essential to the design of offset projects, is often lacking. Here, based on data on vegetation carbon, climate and soil, we quantify the potential for carbon storage in woody vegetation across tropical Africa. The ability of offset projects to produce co-benefits for ecosystems and people is then quantified. When co-benefits such as biodiversity conservation are considered, the top-ranked sites are sometimes different to sites selected purely for their carbon-stocking potential, although they still possess up to 92% of the latter carbon-stocking potential. This work provides the first continental-scale assessment of which areas may provide the greatest direct and indirect benefits from carbon storage reforestation projects at the smallest costs and risks, providing crucial information for prioritization of investments in carbon storage projects.

  5. Digital mapping of soil organic carbon contents and stocks in Denmark.

    Science.gov (United States)

    Adhikari, Kabindra; Hartemink, Alfred E; Minasny, Budiman; Bou Kheir, Rania; Greve, Mette B; Greve, Mogens H

    2014-01-01

    Estimation of carbon contents and stocks are important for carbon sequestration, greenhouse gas emissions and national carbon balance inventories. For Denmark, we modeled the vertical distribution of soil organic carbon (SOC) and bulk density, and mapped its spatial distribution at five standard soil depth intervals (0-5, 5-15, 15-30, 30-60 and 60-100 cm) using 18 environmental variables as predictors. SOC distribution was influenced by precipitation, land use, soil type, wetland, elevation, wetness index, and multi-resolution index of valley bottom flatness. The highest average SOC content of 20 g kg(-1) was reported for 0-5 cm soil, whereas there was on average 2.2 g SOC kg(-1) at 60-100 cm depth. For SOC and bulk density prediction precision decreased with soil depth, and a standard error of 2.8 g kg(-1) was found at 60-100 cm soil depth. Average SOC stock for 0-30 cm was 72 t ha(-1) and in the top 1 m there was 120 t SOC ha(-1). In total, the soils stored approximately 570 Tg C within the top 1 m. The soils under agriculture had the highest amount of carbon (444 Tg) followed by forest and semi-natural vegetation that contributed 11% of the total SOC stock. More than 60% of the total SOC stock was present in Podzols and Luvisols. Compared to previous estimates, our approach is more reliable as we adopted a robust quantification technique and mapped the spatial distribution of SOC stock and prediction uncertainty. The estimation was validated using common statistical indices and the data and high-resolution maps could be used for future soil carbon assessment and inventories. PMID:25137066

  6. Digital mapping of soil organic carbon contents and stocks in Denmark.

    Directory of Open Access Journals (Sweden)

    Kabindra Adhikari

    Full Text Available Estimation of carbon contents and stocks are important for carbon sequestration, greenhouse gas emissions and national carbon balance inventories. For Denmark, we modeled the vertical distribution of soil organic carbon (SOC and bulk density, and mapped its spatial distribution at five standard soil depth intervals (0-5, 5-15, 15-30, 30-60 and 60-100 cm using 18 environmental variables as predictors. SOC distribution was influenced by precipitation, land use, soil type, wetland, elevation, wetness index, and multi-resolution index of valley bottom flatness. The highest average SOC content of 20 g kg(-1 was reported for 0-5 cm soil, whereas there was on average 2.2 g SOC kg(-1 at 60-100 cm depth. For SOC and bulk density prediction precision decreased with soil depth, and a standard error of 2.8 g kg(-1 was found at 60-100 cm soil depth. Average SOC stock for 0-30 cm was 72 t ha(-1 and in the top 1 m there was 120 t SOC ha(-1. In total, the soils stored approximately 570 Tg C within the top 1 m. The soils under agriculture had the highest amount of carbon (444 Tg followed by forest and semi-natural vegetation that contributed 11% of the total SOC stock. More than 60% of the total SOC stock was present in Podzols and Luvisols. Compared to previous estimates, our approach is more reliable as we adopted a robust quantification technique and mapped the spatial distribution of SOC stock and prediction uncertainty. The estimation was validated using common statistical indices and the data and high-resolution maps could be used for future soil carbon assessment and inventories.

  7. Aboveground carbon in Quebec forests: stock quantification at the provincial scale and assessment of temperature, precipitation and edaphic properties effects on the potential stand-level stocking.

    Science.gov (United States)

    Duchesne, Louis; Houle, Daniel; Ouimet, Rock; Lambert, Marie-Claude; Logan, Travis

    2016-01-01

    Biological carbon sequestration by forest ecosystems plays an important role in the net balance of greenhouse gases, acting as a carbon sink for anthropogenic CO2 emissions. Nevertheless, relatively little is known about the abiotic environmental factors (including climate) that control carbon storage in temperate and boreal forests and consequently, about their potential response to climate changes. From a set of more than 94,000 forest inventory plots and a large set of spatial data on forest attributes interpreted from aerial photographs, we constructed a fine-resolution map (∼375 m) of the current carbon stock in aboveground live biomass in the 435,000 km(2) of managed forests in Quebec, Canada. Our analysis resulted in an area-weighted average aboveground carbon stock for productive forestland of 37.6 Mg ha(-1), which is lower than commonly reported values for similar environment. Models capable of predicting the influence of mean annual temperature, annual precipitation, and soil physical environment on maximum stand-level aboveground carbon stock (MSAC) were developed. These models were then used to project the future MSAC in response to climate change. Our results indicate that the MSAC was significantly related to both mean annual temperature and precipitation, or to the interaction of these variables, and suggest that Quebec's managed forests MSAC may increase by 20% by 2041-2070 in response to climate change. Along with changes in climate, the natural disturbance regime and forest management practices will nevertheless largely drive future carbon stock at the landscape scale. Overall, our results allow accurate accounting of carbon stock in aboveground live tree biomass of Quebec's forests, and provide a better understanding of possible feedbacks between climate change and carbon storage in temperate and boreal forests. PMID:26966680

  8. Carbon stock loss from deforestation through 2013 in Brazilian Amazonia.

    Science.gov (United States)

    Nogueira, Euler Melo; Yanai, Aurora M; Fonseca, Frederico O R; Fearnside, Philip Martin

    2015-03-01

    The largest carbon stock in tropical vegetation is in Brazilian Amazonia. In this ~5 million km(2) area, over 750,000 km(2) of forest and ~240,000 km(2) of nonforest vegetation types had been cleared through 2013. We estimate current carbon stocks and cumulative gross carbon loss from clearing of premodern vegetation in Brazil's 'Legal Amazonia' and 'Amazonia biome' regions. Biomass of 'premodern' vegetation (prior to major increases in disturbance beginning in the 1970s) was estimated by matching vegetation classes mapped at a scale of 1 : 250,000 and 29 biomass means from 41 published studies for vegetation types classified as forest (2317 1-ha plots) and as either nonforest or contact zones (1830 plots and subplots of varied size). Total biomass (above and below-ground, dry weight) underwent a gross reduction of 18.3% in Legal Amazonia (13.1 Pg C) and 16.7% in the Amazonia biome (11.2 Pg C) through 2013, excluding carbon loss from the effects of fragmentation, selective logging, fires, mortality induced by recent droughts and clearing of forest regrowth. In spite of the loss of carbon from clearing, large amounts of carbon were stored in stands of remaining vegetation in 2013, equivalent to 149 Mg C ha(-1) when weighted by the total area covered by each vegetation type in Legal Amazonia. Native vegetation in Legal Amazonia in 2013 originally contained 58.6 Pg C, while that in the Amazonia biome contained 56 Pg C. Emissions per unit area from clearing could potentially be larger in the future because previously cleared areas were mainly covered by vegetation with lower mean biomass than the remaining vegetation. Estimates of original biomass are essential for estimating losses to forest degradation. This study offers estimates of cumulative biomass loss, as well as estimates of premodern carbon stocks that have not been represented in recent estimates of deforestation impacts. PMID:25380507

  9. Mountain pine beetle impacts on vegetation and carbon stocks

    Science.gov (United States)

    Hawbaker, Todd J.; Briggs, Jennifer S.; Caldwell, Megan K.; Stitt, Susan

    2013-01-01

    In the Southern Rocky Mountains, an epidemic outbreak of mountain pine beetle (Dendroctonus ponderosae; MPB) has caused levels of tree mortality unprecedented in recorded history. The impacts of this mortality on vegetation composition, forest structure, and carbon stocks have only recently received attention, although the impacts of other disturbances such as fires and land-use/land-cover change are much better known. This study, initiated in 2010, aims to increase our understanding of MPB outbreaks and their impacts. We have integrated field-collected data with vegetation simulation models to assess and quantify how long-term patterns of vegetation and carbon stocks have and may change in response to MPB outbreaks and other disturbances.

  10. Biomass and Carbon Stocks of Sofala Bay Mangrove Forests

    Directory of Open Access Journals (Sweden)

    Almeida A. Sitoe

    2014-08-01

    Full Text Available Mangroves could be key ecosystems in strategies addressing the mitigation of climate changes through carbon storage. However, little is known regarding the carbon stocks of these ecosystems, particularly below-ground. This study was carried out in the mangrove forests of Sofala Bay, Central Mozambique, with the aim of quantifying carbon stocks of live and dead plant and soil components. The methods followed the procedures developed by the Center for International Forestry Research (CIFOR for mangrove forests. In this study, we developed a general allometric equation to estimate individual tree biomass and soil carbon content (up to 100 cm depth. We estimated the carbon in the whole mangrove ecosystem of Sofala Bay, including dead trees, wood debris, herbaceous, pneumatophores, litter and soil. The general allometric equation for live trees derived was [Above-ground tree dry weight (kg = 3.254 × exp(0.065 × DBH], root mean square error (RMSE = 4.244, and coefficient of determination (R2 = 0.89. The average total carbon storage of Sofala Bay mangrove was 218.5 Mg·ha−1, of which around 73% are stored in the soil. Mangrove conservation has the potential for REDD+ programs, especially in regions like Mozambique, which contains extensive mangrove areas with high deforestation and degradation rates.

  11. Carbon stock changes in forest soils under warming

    Czech Academy of Sciences Publication Activity Database

    Janouš, Dalibor; Pavelka, Marian; Macků, J.; Havránková, Kateřina; Dařenová, Eva; Marek, Michal V.

    Vídeň: European Geosciences Union, 2010. s. 11107-11107. [EGU General Assembly 2010. 03.05.2010-07.05.2010, Vídeň] R&D Projects: GA MŽP(CZ) SP/1A6/108/07; GA MŠk OC08021; GA MŠk 2B06068 Institutional research plan: CEZ:AV0Z60870520 Keywords : forest * carbon stock * warming Subject RIV: GK - Forestry

  12. Underestimation of boreal soil carbon stocks by mathematical soil carbon models linked to soil nutrient status

    Science.gov (United States)

    Ťupek, Boris; Ortiz, Carina A.; Hashimoto, Shoji; Stendahl, Johan; Dahlgren, Jonas; Karltun, Erik; Lehtonen, Aleksi

    2016-08-01

    Inaccurate estimate of the largest terrestrial carbon pool, soil organic carbon (SOC) stock, is the major source of uncertainty in simulating feedback of climate warming on ecosystem-atmosphere carbon dioxide exchange by process-based ecosystem and soil carbon models. Although the models need to simplify complex environmental processes of soil carbon sequestration, in a large mosaic of environments a missing key driver could lead to a modeling bias in predictions of SOC stock change.We aimed to evaluate SOC stock estimates of process-based models (Yasso07, Q, and CENTURY soil sub-model v4) against a massive Swedish forest soil inventory data set (3230 samples) organized by a recursive partitioning method into distinct soil groups with underlying SOC stock development linked to physicochemical conditions.For two-thirds of measurements all models predicted accurate SOC stock levels regardless of the detail of input data, e.g., whether they ignored or included soil properties. However, in fertile sites with high N deposition, high cation exchange capacity, or moderately increased soil water content, Yasso07 and Q models underestimated SOC stocks. In comparison to Yasso07 and Q, accounting for the site-specific soil characteristics (e. g. clay content and topsoil mineral N) by CENTURY improved SOC stock estimates for sites with high clay content, but not for sites with high N deposition.Our analysis suggested that the soils with poorly predicted SOC stocks, as characterized by the high nutrient status and well-sorted parent material, indeed have had other predominant drivers of SOC stabilization lacking in the models, presumably the mycorrhizal organic uptake and organo-mineral stabilization processes. Our results imply that the role of soil nutrient status as regulator of organic matter mineralization has to be re-evaluated, since correct SOC stocks are decisive for predicting future SOC change and soil CO2 efflux.

  13. Mapping organic carbon stocks of Swiss forest soil

    Science.gov (United States)

    Nussbaum, M.; Papritz, A.; Baltensweiler, A.; Walthert, L.

    2012-04-01

    Carbon (C) sequestration into forest sinks offsets greenhouse gas emissions under the Kyoto protocol. Therefore, quantifying C stocks and fluxes in forest ecosystems is of interest for reporting greenhouse gas emissions. In Switzerland, the National Forest Inventory offers comprehensive data to quantify the above ground forest biomass and its change in time. Estimating stocks of soil organic C (SOC) in forests is more difficult because of its high spatial variability. To date the greenhouse gas inventory relies only on sparse data and regionally differentiated predictions of SOC stocks in forest soils are currently not possible. Recently, more soil data and new explanatory variables for statistical modeling like high resolution elevation data and satellite images became available. Based on data from 1'033 sites, we modeled SOC stocks to a depth of 1 m including the organic layer for the Swiss forested area. We used a novel robust restricted maximum likelihood method to fit a linear regression model with spatially correlated errors to the C stock data. For the regression analysis we used a broad range of covariates derived from climate data (precipitation, temperature, radiation), two elevation models (resolutions 25 and 2 m) and spectral variables representing vegetation. Furthermore, the main cartographic categories of an overview soil map were used to broadly represent the parent material. The numerous covariates, that partly correlated strongly, were reduced to a first subset using LASSO (Least Absolute Shrinkage and Selection Operator). This subset of covariates was then further reduced based on cross validation of the robustly fitted spatial model. The levels of categorical covariates were partly aggregated during this process and interactions between covariates were explored to account for nonlinear dependence of C stocks on the covariates. Using the final model, robust kriging prediction and error maps were computed with a resolution of one hectare.

  14. Effect of tree species on carbon stocks in forest floor and mineral soil and implications for soil carbon inventories

    NARCIS (Netherlands)

    Schulp, C.J.E.; Nabuurs, G.J.; Verburg, P.H.; Waal, de R.W.

    2008-01-01

    Forest soil organic carbon (SOC) and forest floor carbon (FFC) stocks are highly variable. The sampling effort required to assess SOC and FFC stocks is therefore large, resulting in limited sampling and poor estimates of the size, spatial distribution, and changes in SOC and FFC stocks in many count

  15. Windthrows increase soil carbon stocks in a central Amazon forest

    Science.gov (United States)

    dos Santos, Leandro T.; Magnabosco Marra, Daniel; Trumbore, Susan; de Camargo, Plínio B.; Negrón-Juárez, Robinson I.; Lima, Adriano J. N.; Ribeiro, Gabriel H. P. M.; dos Santos, Joaquim; Higuchi, Niro

    2016-03-01

    Windthrows change forest structure and species composition in central Amazon forests. However, the effects of widespread tree mortality associated with wind disturbances on soil properties have not yet been described in this vast region. We investigated short-term effects (7 years after disturbance) of widespread tree mortality caused by a squall line event from mid-January of 2005 on soil carbon stocks and concentrations in a central Amazon terra firme forest. The soil carbon stock (averaged over a 0-30 cm depth profile) in disturbed plots (61.4 ± 8.2 Mg ha-1, mean ±95 % confidence interval) was marginally higher (p = 0.09) than that from undisturbed plots (47.7 ± 13.6 Mg ha-1). The soil organic carbon concentration in disturbed plots (2.0 ± 0.17 %) was significantly higher (p < 0.001) than that from undisturbed plots (1.36 ± 0.24 %). Moreover, soil carbon stocks were positively correlated with soil clay content (r2 = 0.332, r = 0.575 and p = 0.019) and with tree mortality intensity (r2 = 0.257, r = 0.506 and p = 0.045). Our results indicate that large inputs of plant litter associated with large windthrow events cause a short-term increase in soil carbon content, and the degree of increase is related to soil clay content and tree mortality intensity. The higher carbon content and potentially higher nutrient availability in soils from areas recovering from windthrows may favor forest regrowth and increase vegetation resilience.

  16. Degradation in carbon stocks near tropical forest edges

    OpenAIRE

    Chaplin-Kramer, Rebecca; Ramler, Ivan; Sharp, Richard; Haddad, Nick M.; Gerber, James S.; West, Paul C.; Mandle, Lisa; Engstrom, Peder; Baccini, Alessandro; Sim, Sarah; Mueller, Carina; King, Henry

    2015-01-01

    Carbon stock estimates based on land cover type are critical for informing climate change assessment and landscape management, but field and theoretical evidence indicates that forest fragmentation reduces the amount of carbon stored at forest edges. Here, using remotely sensed pantropical biomass and land cover data sets, we estimate that biomass within the first 500 m of the forest edge is on average 25% lower than in forest interiors and that reductions of 10% extend to 1.5 km from the for...

  17. Biomass and carbon stock in Jatropha curcas L.

    OpenAIRE

    Carlos Moreira Miquelino Eleto Torres; Laércio Antônio Gonçalves Jacovine; Diego de Paula Toledo; Carlos Pedro Boechat Soares; Sabina Cerruto Ribeiro; Maria Cristina Martins

    2011-01-01

    This study aims to quantify the biomass and carbon stock in a crop of physic nut Jatropha curcas in Viçosa-MG at age three years. For biomass quantification, the direct or destructive method was applied to sample plants selected according to height, crown diameter and number of branches. For the determination of dry biomass in the field, the proportionality method was used. The determination of total carbon content was done in the Laboratory of Forest Soils of the Federal University of Viçosa...

  18. Estimating carbon stock in secondary forests: decisions and uncertainties associated with allometric biomass models.

    NARCIS (Netherlands)

    Breugel, van M.; Ransijn, J.; Craven, D.; Bongers, F.; Hall, J.

    2011-01-01

    Secondary forests are a major terrestrial carbon sink and reliable estimates of their carbon stocks are pivotal for understanding the global carbon balance and initiatives to mitigate CO2 emissions through forest management and reforestation. A common method to quantify carbon stocks in forests is t

  19. Land use change and carbon stock dynamics in Sub-Saharan Africa - Case study of Western Africa - Ghana

    Science.gov (United States)

    Grieco, E.; Chiti, T.; Valentini, R.

    2012-04-01

    currently reports data on soil carbon, although emissions from soils following deforestation are likely to be significant in many cases. Despite the common understanding about the effects of deforestation on different compartments in terms of carbon stocks (e.g. disappearance of biomass ) variations in soil carbon are much less perceptible, even after a radical change in land use . This study brings in the spotlight the soil reaction to radical land use change in the long run demonstrating that it is not so trifle as commonly believed. Importance of considering soil carbon stock for accounting land use change dynamics is not properly recognized in the international deforestation policies and its influence in mitigating climate change is nowadays neglected but it is really not negligible.

  20. Biomass and carbon stock in Jatropha curcas L.

    Directory of Open Access Journals (Sweden)

    Carlos Moreira Miquelino Eleto Torres

    2011-09-01

    Full Text Available This study aims to quantify the biomass and carbon stock in a crop of physic nut Jatropha curcas in Viçosa-MG at age three years. For biomass quantification, the direct or destructive method was applied to sample plants selected according to height, crown diameter and number of branches. For the determination of dry biomass in the field, the proportionality method was used. The determination of total carbon content was done in the Laboratory of Forest Soils of the Federal University of Viçosa, and the estimation of CO2 equivalent was based on the 3.67 factor. The carbon stock found in the third year of cultivation was 4.182 tC.ha-1 (15.349 tCO2-e.ha-1 and the mean annual increment (MAI was 1.394 tC.ha-1.year-1. Results revealed that the potential carbon increment in the physic nut crop is similar to values found in other crops and natural forests yet lower than in eucalyptus crops.

  1. Clay content drives carbon stocks in soils under a plantation of Eucalyptus saligna Labill. in southern Brazil

    Directory of Open Access Journals (Sweden)

    Tanise Luisa Sausen

    2014-06-01

    Full Text Available Soil carbon accumulation is largely dependent on net primary productivity. To our knowledge, there have been no studies investigating the dynamics of carbon accumulation in weathered subtropical soils, especially in managed eucalyptus plantations. We quantified the seasonal input of leaf litter, the leaf decomposition rate and soil carbon stocks in an commercial plantation of Eucalyptus saligna Labill. in southern Brazil. Our goal was to evaluate, through multiple linear regression, the influence that certain chemical characteristics of litter, as well as chemical and physical characteristics of soil, have on carbon accumulation in soil organic matter fractions. Variables related to the chemical composition of litter were not associated with the soil carbon stock in the particulate and mineral fractions. However, certain soil characteristics were significantly associated with the carbon stock in both fractions. The concentrations of nutrients associated with plant growth and productivity, such as phosphorus, sulfur, copper and zinc, were associated with variations in the labile carbon pool (particulate fraction. Clay content was strongly associated with the carbon stock in the mineral fraction. The carbon accumulation and stabilization in weathered subtropical Ultisol seems to be mainly associated with the intrinsic characteristics of the soil, particularly clay content, rather than with the quantity, chemical composition or decomposition rate of the litter.

  2. Effects of land management on large trees and carbon stocks

    Directory of Open Access Journals (Sweden)

    P. E. Kauppi

    2014-02-01

    Full Text Available Large trees are important and unique organisms in forests, providing ecosystem services including carbon dioxide removal from the atmosphere and long-term storage. There is concern about reports of global decline of big trees. Based on observations from Finland and the United States we report that trends of big trees during recent decades have been surprisingly variable among regions. In southern Finland, the growing stock volume of trees larger than 30 cm at breast height increased nearly five-fold during the second half of the 20th century, yet more recently ceased to expand. In the United States, large hardwood trees have become increasingly common since the 1950s, while large softwood trees declined until the mid 1990's as a consequence of harvests in the Pacific region, and then rebounded when harvesting there was reduced. We conclude that in the regions studied, the history of land use and forest management governs changes of tree populations especially with reference to large trees. Large trees affect greatly the carbon density of forests and usually have deeper roots and relatively lower mortality than small trees. An accumulating stock of large trees in forests may have negligible direct biophysical effects on climate because from changes in transpiration or forest albedo. Large trees have particular ecological importance and often constitute an unusually large proportion of biomass carbon stocks in a forest. Understanding the changes in big tree distributions in different regions of the world and the demography of tree populations makes a contribution to estimating the past impact and future potential of the role of forests in the global carbon budget.

  3. Influence of fish behaviour on fish stock abundance estimations

    OpenAIRE

    Fréon, Pierre; Gerlotto, François

    1988-01-01

    A new methodolgy is proposed for studying fish school behaviour, allowing to quantify its influence on stock abundance estimations. Observations are collected in open sea or inside a large net set in shallow waters. Preliminary results concerning fish reactions show a modification of the school structure under a research vessel using acoustic devices for abundance measurements. The school structure, even when the fish is not disturbed, shows an irregular density distribution in opposition to ...

  4. The uncertainty of modeled soil carbon stock change for Finland

    Science.gov (United States)

    Lehtonen, Aleksi; Heikkinen, Juha

    2013-04-01

    Countries should report soil carbon stock changes of forests for Kyoto Protocol. Under Kyoto Protocol one can omit reporting of a carbon pool by verifying that the pool is not a source of carbon, which is especially tempting for the soil pool. However, verifying that soils of a nation are not a source of carbon in given year seems to be nearly impossible. The Yasso07 model was parametrized against various decomposition data using MCMC method. Soil carbon change in Finland between 1972 and 2011 were simulated with Yasso07 model using litter input data derived from the National Forest Inventory (NFI) and fellings time series. The uncertainties of biomass models, litter turnoverrates, NFI sampling and Yasso07 model were propagated with Monte Carlo simulations. Due to biomass estimation methods, uncertainties of various litter input sources (e.g. living trees, natural mortality and fellings) correlate strongly between each other. We show how original covariance matrices can be analytically combined and the amount of simulated components reduce greatly. While doing simulations we found that proper handling correlations may be even more essential than accurate estimates of standard errors. As a preliminary results, from the analysis we found that both Southern- and Northern Finland were soil carbon sinks, coefficient of variations (CV) varying 10%-25% when model was driven with long term constant weather data. When we applied annual weather data, soils were both sinks and sources of carbon and CVs varied from 10%-90%. This implies that the success of soil carbon sink verification depends on the weather data applied with models. Due to this fact IPCC should provide clear guidance for the weather data applied with soil carbon models and also for soil carbon sink verification. In the UNFCCC reporting carbon sinks of forest biomass have been typically averaged for five years - similar period for soil model weather data would be logical.

  5. Accounting for biomass carbon stock change due to wildfire in temperate forest landscapes in Australia.

    Directory of Open Access Journals (Sweden)

    Heather Keith

    Full Text Available Carbon stock change due to forest management and disturbance must be accounted for in UNFCCC national inventory reports and for signatories to the Kyoto Protocol. Impacts of disturbance on greenhouse gas (GHG inventories are important for many countries with large forest estates prone to wildfires. Our objective was to measure changes in carbon stocks due to short-term combustion and to simulate longer-term carbon stock dynamics resulting from redistribution among biomass components following wildfire. We studied the impacts of a wildfire in 2009 that burnt temperate forest of tall, wet eucalypts in south-eastern Australia. Biomass combusted ranged from 40 to 58 tC ha(-1, which represented 6-7% and 9-14% in low- and high-severity fire, respectively, of the pre-fire total biomass carbon stock. Pre-fire total stock ranged from 400 to 1040 tC ha(-1 depending on forest age and disturbance history. An estimated 3.9 TgC was emitted from the 2009 fire within the forest region, representing 8.5% of total biomass carbon stock across the landscape. Carbon losses from combustion were large over hours to days during the wildfire, but from an ecosystem dynamics perspective, the proportion of total carbon stock combusted was relatively small. Furthermore, more than half the stock losses from combustion were derived from biomass components with short lifetimes. Most biomass remained on-site, although redistributed from living to dead components. Decomposition of these components and new regeneration constituted the greatest changes in carbon stocks over ensuing decades. A critical issue for carbon accounting policy arises because the timeframes of ecological processes of carbon stock change are longer than the periods for reporting GHG inventories for national emissions reductions targets. Carbon accounts should be comprehensive of all stock changes, but reporting against targets should be based on human-induced changes in carbon stocks to incentivise

  6. Accounting for biomass carbon stock change due to wildfire in temperate forest landscapes in Australia.

    Science.gov (United States)

    Keith, Heather; Lindenmayer, David B; Mackey, Brendan G; Blair, David; Carter, Lauren; McBurney, Lachlan; Okada, Sachiko; Konishi-Nagano, Tomoko

    2014-01-01

    Carbon stock change due to forest management and disturbance must be accounted for in UNFCCC national inventory reports and for signatories to the Kyoto Protocol. Impacts of disturbance on greenhouse gas (GHG) inventories are important for many countries with large forest estates prone to wildfires. Our objective was to measure changes in carbon stocks due to short-term combustion and to simulate longer-term carbon stock dynamics resulting from redistribution among biomass components following wildfire. We studied the impacts of a wildfire in 2009 that burnt temperate forest of tall, wet eucalypts in south-eastern Australia. Biomass combusted ranged from 40 to 58 tC ha(-1), which represented 6-7% and 9-14% in low- and high-severity fire, respectively, of the pre-fire total biomass carbon stock. Pre-fire total stock ranged from 400 to 1040 tC ha(-1) depending on forest age and disturbance history. An estimated 3.9 TgC was emitted from the 2009 fire within the forest region, representing 8.5% of total biomass carbon stock across the landscape. Carbon losses from combustion were large over hours to days during the wildfire, but from an ecosystem dynamics perspective, the proportion of total carbon stock combusted was relatively small. Furthermore, more than half the stock losses from combustion were derived from biomass components with short lifetimes. Most biomass remained on-site, although redistributed from living to dead components. Decomposition of these components and new regeneration constituted the greatest changes in carbon stocks over ensuing decades. A critical issue for carbon accounting policy arises because the timeframes of ecological processes of carbon stock change are longer than the periods for reporting GHG inventories for national emissions reductions targets. Carbon accounts should be comprehensive of all stock changes, but reporting against targets should be based on human-induced changes in carbon stocks to incentivise mitigation activities

  7. Organic carbon concentrations and stocks in Romanian mineral forest soils

    Directory of Open Access Journals (Sweden)

    Lucian C. Dincă

    2012-11-01

    Full Text Available Estimating soils organic carbon stock and its change in time isan actual concern for scientists and climate change policy makers. Thepresent article firstly focus on determination of C stocks in Romania on forest soil types, as well as development of the spatial distribution mapping using a Geographic Information System (GIS and also the secondly on the quantification of uncertainty associated with currently available data on C concentration on forest soils geometrical layers. Determination of C stock was done based on forest management plans database created over 2000-2006. Unlike original database, the data for this study was harmonized on following depths: 0-10 cm, 10-20 cm, 20-40 cm, and > 40 cm. Then, the obtained values were grouped by soil types, resulting average values for the main forest soils from Romania. A soil area weighted average value of 137 t/ha is calculated for Romania, in the range of estimationsfor other European geographic and climatic areas. The soils that have the largest amount of organic carbon are andosols, vertisols, entic and haplic podzols, whereas the ones that have the smallest values of organic carbon are solonetz and solonchaks. Although current assessment relies on very large number of samples from the forest management planning database, the variability of C concentration remains very large, ~40-50% for coefficient the variation and ~100% of the average, when defining the range of 95% of entire soil population, rather showing the variability than uncertainty of the average estimated. Best fit for C concentration on geometric layersin any forest soil is asymmetric, associated with log-normal distributions.

  8. Organic carbon concentrations and stocks in Romanian mineral forest soils

    Directory of Open Access Journals (Sweden)

    Lucian C. Dincă

    2012-12-01

    Full Text Available Estimating soils organic carbon stock and its change in time is an actual concern for scientists and climate change policy makers. The present article firstly focus on determination of C stocks in Romania on forest soil types, as well as development of the spatial distribution mapping using a Geographic Information System (GIS and also the secondly on the quantification of uncertainty associated with currently available data on C concentration on forest soils geometrical layers. Determination of C stock was done based on forest management plans database created over 2000-2006. Unlike original database, the data for this study was harmonized on following depths: 0-10 cm, 10-20 cm, 20-40 cm, and > 40 cm. Then, the obtained values were grouped by soil types, resulting average values for the main forest soils from Romania. A soil area weighted average value of 137 t/ha is calculated for Romania, in the range of estimations for other European geographic and climatic areas. The soils that have the largest amount of organic carbon are andosols, vertisols, entic and haplic podzols, whereas the ones that have the smallest values of organic carbon are solonetz and solonchaks. Although current assessment relies on very large number of samples from the forest management planning database, the variability of C concentration remains very large, ~40-50% for coefficient the variation and ~100% of the average, when defining the range of 95% of entire soil population, rather showing the variability than uncertainty of the average estimated. Best fit for C concentration on geometric layers in any forest soil is asymmetric, associated with log-normal distributions.

  9. Carbon stocks of intact mangroves and carbon emissions arising from their conversion in the Dominican Republic.

    Science.gov (United States)

    Kauffman, J Boone; Heider, Chris; Norfolk, Jennifer; Payton, Frederick

    2014-04-01

    Mangroves are recognized to possess a variety of ecosystem services including high rates of carbon sequestration and storage. Deforestation and conversion of these ecosystems continue to be high and have been predicted to result in significant carbon emissions to the atmosphere. Yet few studies have quantified the carbon stocks or losses associated with conversion of these ecosystems. In this study we quantified the ecosystem carbon stocks of three common mangrove types of the Caribbean as well as those of abandoned shrimp ponds in areas formerly occupied by mangrove-a common land-use conversion of mangroves throughout the world. In the mangroves of the Montecristi Province in Northwest Dominican Republic we found C stocks ranged from 706 to 1131 Mg/ha. The medium-statured mangroves (3-10 m in height) had the highest C stocks while the tall (> 10 m) mangroves had the lowest ecosystem carbon storage. Carbon stocks of the low mangrove (shrub) type (carbon-rich soils as deep as 2 m. Carbon stocks of abandoned shrimp ponds were 95 Mg/ha or approximately 11% that of the mangroves. Using a stock-change approach, the potential emissions from the conversion of mangroves to shrimp ponds ranged from 2244 to 3799 Mg CO2e/ha (CO2 equivalents). This is among the largest measured C emissions from land use in the tropics. The 6260 ha of mangroves and converted mangroves in the Montecristi Province are estimated to contain 3,841,490 Mg of C. Mangroves represented 76% of this area but currently store 97% of the carbon in this coastal wetland (3,696,722 Mg C). Converted lands store only 4% of the total ecosystem C (144,778 Mg C) while they comprised 24% of the area. By these metrics the replacement of mangroves with shrimp and salt ponds has resulted in estimated emissions from this region totaling 3.8 million Mg CO2e or approximately 21% of the total C prior to conversion. Given the high C stocks of mangroves, the high emissions from their conversion, and the other important

  10. Impact of seagrass loss and subsequent revegetation on carbon sequestration and stocks

    OpenAIRE

    Marbà, Núria; Arias-Ortiz, Ariane; Masqué, Pere; Kendrick, Gary A.; Mazarrasa, Inés; Bastyan, Geoff R.; García-Orellana, Jordi; Duarte, Carlos M.

    2015-01-01

    © 2015 British Ecological Society. Seagrass meadows are sites of high rates of carbon sequestration and they potentially support 'blue carbon' strategies to mitigate anthropogenic CO2 emissions. Current uncertainties on the fate of carbon stocks following the loss or revegetation of seagrass meadows prevent the deployment of 'blue carbon' strategies. Here, we reconstruct the trajectories of carbon stocks associated with one of the longest monitored seagrass restoration projects globally. We d...

  11. Carbon Stocks of Tropical Coastal Wetlands within the Karstic Landscape of the Mexican Caribbean

    OpenAIRE

    Maria Fernanda Adame; J Boone Kauffman; Israel Medina; Gamboa, Julieta N.; Olmo Torres; Caamal, Juan P.; Miriam Reza; Herrera-Silveira, Jorge A.

    2013-01-01

    Coastal wetlands can have exceptionally large carbon (C) stocks and their protection and restoration would constitute an effective mitigation strategy to climate change. Inclusion of coastal ecosystems in mitigation strategies requires quantification of carbon stocks in order to calculate emissions or sequestration through time. In this study, we quantified the ecosystem C stocks of coastal wetlands of the Sian Ka'an Biosphere Reserve (SKBR) in the Yucatan Peninsula, Mexico. We stratified the...

  12. Land-cover effects on soil organic carbon stocks in a European city

    OpenAIRE

    Edmondson, Jill L.; Davies, Zoe G; McCormack, Sarah A.; Gaston, Kevin J.; Leake, Jonathan R.

    2014-01-01

    Soil is the vital foundation of terrestrial ecosystems storing water, nutrients, and almost three-quarters of the organic carbon stocks of the Earth's biomes. Soil organic carbon (SOC) stocks vary with land-cover and land-use change, with significant losses occurring through disturbance and cultivation. Although urbanisation is a growing contributor to land-use change globally, the effects of urban land-cover types on SOC stocks have not been studied for densely built cities. Additionally, th...

  13. Modelling soil organic carbon stocks along topographic transects under climate change scenarios using CarboSOIL

    Science.gov (United States)

    Kotb Abd-Elmabod, Sameh; Muñoz-Rojas, Miriam; Jordán, Antonio; Anaya-Romero, María; de la Rosa, Diego

    2014-05-01

    CarboSOIL is a land evaluation model for soil organic carbon (SOC) accounting under global change scenarios (Muñoz-Rojas et al., 2013a; 2013b) and is a new component of the MicroLEIS Decision Support System. MicroLEIS is a tool for decision-makers dealing with specific agro-ecological problems as, for example, soil contamination risks (Abd-Elmabod et al., 2010; Abd-Elmabod et al., 2012)which has been designed as a knowledge-based approach incorporating a set of interlinked data bases. Global change and land use changes in recent decades have caused relevant impacts in vegetation carbon stocks (Muñoz-Rojas et al., 2011) and soil organic carbon stocks, especially in sensible areas as the Mediterranean region (Muñoz-Rojas et al., 2012a; 2012b). This study aims to investigate the influence of topography, climate, land use and soil factors on SOC stocks by the application of CarboSOIL in a representative area of the Mediterranean region (Seville, Spain). Two topographic transects (S-N and W-E oriented) were considered, including 63 points separated 4 km each. These points are associated to 41 soil profiles extracted from the SDBm soil data base (De la Rosa et al., 2001) and climatic information (average minimum temperature, average maximum temperature and average rainfall per month) extracted from raster data bases (Andalusian Environmental Information Network, REDIAM). CarboSOIL has been applied along topographic transects at different soil depths and under different climate change scenarios. Climate scenarios have been calculated according to the global climate model (CNRMCM3) by extracting spatial climate data under IPCC A1B scenario for the current period (average data from 1960-2000), 2040, 2070 and 2100. In the current scenario, results show that the highest SOC stock values located on Typic Haploxeralfs under olive groves for soil sections 0-25 cm and for 25-50 cm, but the highest values were determined on fruit-cropped Rendolic Xerothent in the 50-75cm

  14. Impact of mooring activities on carbon stocks in seagrass meadows

    KAUST Repository

    Serrano, O.

    2016-03-16

    Boating activities are one of the causes that threaten seagrass meadows and the ecosystem services they provide. Mechanical destruction of seagrass habitats may also trigger the erosion of sedimentary organic carbon (Corg) stocks, which may contribute to increasing atmospheric CO2. This study presents the first estimates of loss of Corg stocks in seagrass meadows due to mooring activities in Rottnest Island, Western Australia. Sediment cores were sampled from seagrass meadows and from bare but previously vegetated sediments underneath moorings. The Corg stores have been compromised by the mooring deployment from 1930s onwards, which involved both the erosion of existing sedimentary Corg stores and the lack of further accumulation of Corg. On average, undisturbed meadows had accumulated ~6.4 Kg Corg m−2 in the upper 50 cm-thick deposits at a rate of 34 g Corg m−2 yr−1. The comparison of Corg stores between meadows and mooring scars allows us to estimate a loss of 4.8 kg Corg m−2 in the 50 cm-thick deposits accumulated over ca. 200 yr as a result of mooring deployments. These results provide key data for the implementation of Corg storage credit offset policies to avoid the conversion of seagrass ecosystems and contribute to their preservation.

  15. Impact of mooring activities on carbon stocks in seagrass meadows

    Science.gov (United States)

    Serrano, O.; Ruhon, R.; Lavery, P. S.; Kendrick, G. A.; Hickey, S.; Masqué, P.; Arias-Ortiz, A.; Steven, A.; Duarte, C. M.

    2016-03-01

    Boating activities are one of the causes that threaten seagrass meadows and the ecosystem services they provide. Mechanical destruction of seagrass habitats may also trigger the erosion of sedimentary organic carbon (Corg) stocks, which may contribute to increasing atmospheric CO2. This study presents the first estimates of loss of Corg stocks in seagrass meadows due to mooring activities in Rottnest Island, Western Australia. Sediment cores were sampled from seagrass meadows and from bare but previously vegetated sediments underneath moorings. The Corg stores have been compromised by the mooring deployment from 1930s onwards, which involved both the erosion of existing sedimentary Corg stores and the lack of further accumulation of Corg. On average, undisturbed meadows had accumulated ~6.4 Kg Corg m‑2 in the upper 50 cm-thick deposits at a rate of 34 g Corg m‑2 yr‑1. The comparison of Corg stores between meadows and mooring scars allows us to estimate a loss of 4.8 kg Corg m‑2 in the 50 cm-thick deposits accumulated over ca. 200 yr as a result of mooring deployments. These results provide key data for the implementation of Corg storage credit offset policies to avoid the conversion of seagrass ecosystems and contribute to their preservation.

  16. Implication of Forest-Savanna Dynamics on Biomass and Carbon Stock: Effectiveness of an Amazonian Ecological Station

    Science.gov (United States)

    Couto-Santos, F. R.; Luizao, F. J.

    2014-12-01

    The forests-savanna advancement/retraction process seems to play an important role in the global carbon cycle and in the climate-vegetation balance maintenance in the Amazon. To contribute with long term carbon dynamics and assess effectiveness of a protected area in reduce carbon emissions in Brazilian Amazon transitional areas, variations in forest-savanna mosaics biomass and carbon stock within Maraca Ecological Station (MES), Roraima/Brazil, and its outskirts non-protected areas were compared. Composite surface soil samples and indirect methods based on regression models were used to estimate aboveground tree biomass accumulation and assess vegetation and soil carbon stock along eleven 0.6 ha transects perpendicular to the forest-savanna limits. Aboveground biomass and carbon accumulation were influenced by vegetation structure, showing higher values within protected area, with great contribution of trees above 40 cm in diameter. In the savanna environments of protected areas, a higher tree density and carbon stock up to 30 m from the border confirmed a forest encroachment. This pointed that MES acts as carbon sink, even under variations in soil fertility gradient, with a potential increase of the total carbon stock from 9 to 150 Mg C ha-1. Under 20 years of fire and disturbance management, the results indicated the effectiveness of this protected area to reduce carbon emissions and mitigate greenhouse and climate change effects in a forest-savanna transitional area in Brazilian Northern Amazon. The contribution of this study in understanding rates and reasons for biomass and carbon variation, under different management strategies, should be considered the first approximation to assist policies of reducing emissions from deforestation and forest degradation (REDD) from underresearched Amazonian ecotone; despite further efforts in this direction are still needed. FINANCIAL SUPPORT: Boticário Group Foundation (Fundação Grupo Boticário); National Council for

  17. Estimation of Total Carbon Stocks in Soil and Vegetation of Tropical Peat Forest in Indonesia

    OpenAIRE

    Ujang Suwarna; Elias; Istomo .

    2012-01-01

    The study was conducted in the forest concession area of PT. Diamond Raya Timber, Riau Province, Indonesia.  Measurement and calculation carbon stocks in soil and vegetation of tropical peat forest should be done accurately to anticipate carbon trading.  The objective of the study is to estimate carbon stocks in soil and vegetation in 4 forest conditions.  The study found that biomass and carbon stocks in the soil was 8 times higher than in the vegetation in primary forest condition, and 10 t...

  18. Cointegration analysis and influence rank—A network approach to global stock markets

    Science.gov (United States)

    Yang, Chunxia; Chen, Yanhua; Niu, Lei; Li, Qian

    2014-04-01

    In this paper, cointegration relationships among 26 global stock market indices over the periods of sub-prime and European debt crisis and their influence rank are investigated by constructing and analyzing directed and weighted cointegration networks. The obtained results are shown as follows: the crises have changed cointegration relationships among stock market indices, their cointegration relationship increased after the Lehman Brothers collapse, while the degree of cointegration gradually decreased from the sub-prime to European debt crisis. The influence of US, Japan and China market indices are entirely distinguished over different periods. Before European debt crisis US stock market is a ‘global factor’ which leads the developed and emerging markets, while the influence of US stock market decreased evidently during the European debt crisis. Before sub-prime crisis, there is no significant evidence to show that other stock markets co-move with China stock market, while it becomes more integrated with other markets during the sub-prime and European debt crisis. Among developed and emerging stock markets, the developed stock markets lead the world stock markets before European debt crisis, while due to the shock of sub-prime and European debt crisis, their influences decreased and emerging stock markets replaced them to lead global stock markets.

  19. Is tree species diversity or tree species identity the most important driver of European forest soil carbon stocks?

    Science.gov (United States)

    Vesterdal, Lars; Muhie Dawud, Seid; Raulund-Rasmussen, Karsten; Finér, Leena; Domisch, Timo

    2016-04-01

    Land management includes the selection of specific tree species and tree species mixtures for European forests. Studies of functional species diversity effects have reported positive effects for aboveground carbon (C) sequestration, but the question remains whether higher soil C stocks could also result from belowground niche differentiation including more efficient root exploitation of soils. We studied topsoil C stocks in tree species diversity gradients established within the FunDivEurope project to explore biodiversity-ecosystem functioning relationships in six European forest types in Finland, Poland, Germany, Romania, Spain and Italy. In the Polish forest type we extended the sampling to also include subsoils. We found consistent but modest effects of species diversity on total soil C stocks (forest floor and 0-20 cm) across the six European forest types. Carbon stocks in the forest floor alone and in the combined forest floor and mineral soil layers increased with increasing tree species diversity. In contrast, there was a strong effect of species identity (broadleaf vs. conifer) and its interaction with site-related factors. Within the Polish forest type we sampled soils down to 40 cm and found that species identity was again the main factor explaining total soil C stock. However, species diversity increased soil C stocks in deeper soil layers (20-40 cm), while species identity influenced C stocks significantly within forest floors and the 0-10 cm layer. Root biomass increased with diversity in 30-40 cm depth, and a positive relationship between C stocks and root biomass in the 30-40 cm layer suggested that belowground niche complementarity could be a driving mechanism for higher root carbon input and in turn a deeper distribution of C in diverse forests. We conclude that total C stocks are mainly driven by tree species identity. However, modest positive diversity effects were detected at the European scale, and stronger positive effects on subsoil C stocks

  20. Spatial patterns of soil organic carbon stocks in Estonian arable soils

    Science.gov (United States)

    Suuster, Elsa; Astover, Alar; Kõlli, Raimo; Roostalu, Hugo; Reintam, Endla; Penu, Priit

    2010-05-01

    Soil organic carbon (SOC) determines ecosystem functions, influencing soil fertility, soil physical, chemical and biological properties and crop productivity. Therefore the spatial pattern of SOC stocks and its appropriate management is important at various scales. Due to climate change and the contribution of carbon store in the soils, the national estimates of soil carbon stocks should be determined. Estonian soils have been well studied and mapped at a scale 1:10,000. Previous studies have estimated SOC stocks based on combinations of large groups of Estonian soils and the mean values of the soil profile database, but were not embedded into the geo-referenced databases. These studies have estimated SOC stocks of Estonian arable soils 122.3 Tg. Despite of available soil maps and databases, this information is still very poorly used for spatial soil modelling. The aim of current study is to assess and model spatial pattern of SOC stocks of arable soils on a pilot area Tartu County (area 3089 sq km). Estonian digital soil map and soil monitoring databases are providing a good opportunity to assess SOC stocks at various scales. The qualitative nature of the initial data from a soil map prohibits any straightforward use in modelling. Thus we have used several databases to construct models and linkages between soil properties that can be integrated into soil map. First step was to reorganize the soil map database (44,046 mapping units) so it can be used as an input to modelling. Arable areas were distinguished by a field layer of Agricultural Registers and Information Board, which provides precise information of current land use as it is the basis of paying CAP subsidies. The estimates of SOC content were found by using the arable land evaluation database of Tartu from the Estonian Land Board (comprising 950 sq km and 31,226 fields), where each soil type was assessed separately and average SOC content grouped by texture was derived. SOC content of epipedon varies in

  1. Spatial modeling of the carbon stock of forest trees in Heilongjiang Province, China

    Institute of Scientific and Technical Information of China (English)

    Chang Liu; Lianjun Zhang; Fengri Li; Xingji Jin

    2014-01-01

    Heilongjiang province is the largest forest zone in China and the forest coverage rate is 46%. Forests of Heilongjiang province play an important role in the forest ecosystem of China. In this study we investi-gated the spatial distribution of forest carbon storage in Heilongjiang province using 3083 plots sampled in 2010. We attempted to fit two global models, ordinary least squares model (OLS) , linear mixed model (LMM), and a local model, geographically weighted regression model (GWR), to the relationship between forest carbon content and stand, environment, and climate factors. Five predictors significantly affected forest carbon storage and spatial distribution, viz. average diameter of stand (DBH), number of trees per hectare (TPH), elevation (Elev), slope (Slope) and the product of precipitation and temperature (Rain_Temp). The GWR model outperformed the two global models in both model fitting and prediction because it successfully reduced both spatial auto-correlation and heterogeneity in model residuals. More importantly, the GWR model provided localized model coefficients for each location in the study area, which allowed us to evaluate the influences of local stand conditions and topographic features on tree and stand growth, and forest carbon stock. It also helped us to better understand the impacts of silvi-cultural and management activities on the amount and changes of forest carbon storage across the province. The detailed information can be readily incorporated with the mapping ability of GIS software to provide excellent tools for assessing the distribution and dynamics of the for-est-carbon stock in the next few years.

  2. A large-scale field assessment of carbon stocks in human-modified tropical forests.

    Science.gov (United States)

    Berenguer, Erika; Ferreira, Joice; Gardner, Toby Alan; Aragão, Luiz Eduardo Oliveira Cruz; De Camargo, Plínio Barbosa; Cerri, Carlos Eduardo; Durigan, Mariana; Cosme De Oliveira Junior, Raimundo; Vieira, Ima Célia Guimarães; Barlow, Jos

    2014-12-01

    Tropical rainforests store enormous amounts of carbon, the protection of which represents a vital component of efforts to mitigate global climate change. Currently, tropical forest conservation, science, policies, and climate mitigation actions focus predominantly on reducing carbon emissions from deforestation alone. However, every year vast areas of the humid tropics are disturbed by selective logging, understory fires, and habitat fragmentation. There is an urgent need to understand the effect of such disturbances on carbon stocks, and how stocks in disturbed forests compare to those found in undisturbed primary forests as well as in regenerating secondary forests. Here, we present the results of the largest field study to date on the impacts of human disturbances on above and belowground carbon stocks in tropical forests. Live vegetation, the largest carbon pool, was extremely sensitive to disturbance: forests that experienced both selective logging and understory fires stored, on average, 40% less aboveground carbon than undisturbed forests and were structurally similar to secondary forests. Edge effects also played an important role in explaining variability in aboveground carbon stocks of disturbed forests. Results indicate a potential rapid recovery of the dead wood and litter carbon pools, while soil stocks (0-30 cm) appeared to be resistant to the effects of logging and fire. Carbon loss and subsequent emissions due to human disturbances remain largely unaccounted for in greenhouse gas inventories, but by comparing our estimates of depleted carbon stocks in disturbed forests with Brazilian government assessments of the total forest area annually disturbed in the Amazon, we show that these emissions could represent up to 40% of the carbon loss from deforestation in the region. We conclude that conservation programs aiming to ensure the long-term permanence of forest carbon stocks, such as REDD+, will remain limited in their success unless they effectively

  3. Biomass models to estimate carbon stocks for hardwood tree species

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-Peinado, R.; Montero, G.; Rio, M. del

    2012-11-01

    To estimate forest carbon pools from forest inventories it is necessary to have biomass models or biomass expansion factors. In this study, tree biomass models were developed for the main hardwood forest species in Spain: Alnus glutinosa, Castanea sativa, Ceratonia siliqua, Eucalyptus globulus, Fagus sylvatica, Fraxinus angustifolia, Olea europaea var. sylvestris, Populus x euramericana, Quercus canariensis, Quercus faginea, Quercus ilex, Quercus pyrenaica and Quercus suber. Different tree biomass components were considered: stem with bark, branches of different sizes, above and belowground biomass. For each species, a system of equations was fitted using seemingly unrelated regression, fulfilling the additivity property between biomass components. Diameter and total height were explored as independent variables. All models included tree diameter whereas for the majority of species, total height was only considered in the stem biomass models and in some of the branch models. The comparison of the new biomass models with previous models fitted separately for each tree component indicated an improvement in the accuracy of the models. A mean reduction of 20% in the root mean square error and a mean increase in the model efficiency of 7% in comparison with recently published models. So, the fitted models allow estimating more accurately the biomass stock in hardwood species from the Spanish National Forest Inventory data. (Author) 45 refs.

  4. Soil carbon stocks of Jordan and projected changes upon improved management of croplands

    NARCIS (Netherlands)

    Batjes, N.H.

    2006-01-01

    Inventories of carbon stocks and projected changes at national scale are needed in the context of the Framework Convention on Climate Change (UNFCCC), but uncertainties in the necessary soil data remain large. Soil organic carbon (SOC) and inorganic carbon (SIC) reserves in Jordan were estimated usi

  5. High-resolution forest carbon stocks and emissions in the Amazon

    OpenAIRE

    Gregory P. Asner; Powell, George V. N.; Mascaro, Joseph; Knapp, David E; Clark, John K.; Jacobson, James; Kennedy-Bowdoin, Ty; Balaji, Aravindh; Paez-Acosta, Guayana; Victoria, Eloy; Secada, Laura; Valqui, Michael; Hughes, R. Flint

    2010-01-01

    Efforts to mitigate climate change through the Reduced Emissions from Deforestation and Degradation (REDD) depend on mapping and monitoring of tropical forest carbon stocks and emissions over large geographic areas. With a new integrated use of satellite imaging, airborne light detection and ranging, and field plots, we mapped aboveground carbon stocks and emissions at 0.1-ha resolution over 4.3 million ha of the Peruvian Amazon, an area twice that of all forests in Costa Rica, to reveal the ...

  6. Spatial optimization of carbon-stocking projects across Africa integrating stocking potential with co-benefits and feasibility

    DEFF Research Database (Denmark)

    Greve, Michelle; Reyers, Belinda; Lykke, Anne Mette;

    2013-01-01

    Carbon (C) offset projects through forestation are employed within the emissions trading framework to store C. Yet, information about the potential of landscapes to stock C, essential to the design of offset projects, is often lacking. Based on data on vegetation C, climate and soil we quantified...... costs and risks, providing crucial information for prioritization of investments in C storage projects.......Carbon (C) offset projects through forestation are employed within the emissions trading framework to store C. Yet, information about the potential of landscapes to stock C, essential to the design of offset projects, is often lacking. Based on data on vegetation C, climate and soil we quantified...... the potential for C storage in woody vegetation across tropical Africa. The ability for offset projects to produce co-benefits for ecosystems and local communities was also investigated. When co-benefits such as biodiversity conservation were considered, the top-ranked sites were often different to...

  7. Carbon Stocking in the Natural Forests – The Case of Malaysia

    OpenAIRE

    Jegatheswaran RATNASINGAM; Geetha RAMASAMY; Weiching TOONG; Florin IORAS; Cristina Maria CANJA; Mirabela Ioana LUPU; Ioan Vasile ABRUDAN

    2015-01-01

    Forested land in the world is about 28% of the global land area, accounting for 80% of the terrestrial carbon stored as biomass and soil organic carbon. Human activities, namely fossil fuel combustion and deforestation resulted in anthropogenic emissions into the atmosphere. Deforestation is being focused in this study in view of the role of forests as carbon stocks. Carbon is normally referred to as biomass of the tree. Several studies revealed that carbon is mostly sequestered in the aboveg...

  8. Accurate assessment of Congo basin forest carbon stocks requires forest type specific assessments

    Science.gov (United States)

    Moonen, Pieter C. J.; Van Ballaert, Siege; Verbist, Bruno; Boyemba, Faustin; Muys, Bart

    2014-05-01

    Due to a limited number of field-based studies estimations of carbon stocks in the Central Congo Basin remain highly uncertain. In particular, more information is needed about the variation in stocks between forest types and on the factors explaining these differences. This study presents results from biomass and soil carbon inventories in 46 0.25ha old-growth forest plots located in three study sites in Tshopo District, Democratic Republic of Congo. Four forest community types were identified using cluster and indicator species analysis based on the plots' large tree (>30cm DBH) species composition. Carbon stocks were calculated using newly established forest type specific tree height-diameter relationships to prevent errors related to the use of inappropriate regional relationships from literature. Using the Akaike criterion it became clear that for one site and a few forest types separate tree height-diameter relationships gave a robust and significant better fit, showing that there was a clear and significant interaction effect between sites and forest type. Mean above-ground carbon stocks were estimated at 165 ±44 Mg ha-1. Significant differences were found between forest types, but not between sites for a given forest type. Largest stocks were found in monodominant Gilbertiodendron dewevrei forests (187 ± 37 Mg C ha-1), which occurred in all sites. Smallest stocks (91 ± 14 Mg C ha-1) were found in the Margaritaria discoidea mixed forest type, which occurred only in one site, while two other mixed forest types showed intermediate stocks (148 ± 28 Mg C ha-1 and 160 ± 36 Mg C ha-1 respectively). The observed differences in aboveground stocks between forest types could be explained by forest structure related variables including number of large trees (DBH>70cm), average wood density and dominant height. When comparing the G. dewevrei monodominant type with mixed forest types within each study site, the former showed equal basal area and sometimes higher

  9. Carbon stocks and potential carbon storage in the mangrove forests of China.

    Science.gov (United States)

    Liu, Hongxiao; Ren, Hai; Hui, Dafeng; Wang, Wenqing; Liao, Baowen; Cao, Qingxian

    2014-01-15

    Mangrove forests provide important ecosystem services, and play important roles in terrestrial and oceanic carbon (C) cycling. Although the C stocks or storage in terrestrial ecosystems in China have been frequently assessed, the C stocks in mangrove forests have often been overlooked. In this study, we estimated the C stocks and the potential C stocks in China's mangrove forests by combining our own field data with data from the National Mangrove Resource Inventory Report and from other published literature. The results indicate that mangrove forests in China store about 6.91 ± 0.57 Tg C, of which 81.74% is in the top 1 m soil, 18.12% in the biomass of mangrove trees, and 0.08% in the ground layer (i.e. mangrove litter and seedlings). The potential C stocks are as high as 28.81 ± 4.16 Tg C. On average, mangrove forests in China contain 355.25 ± 82.19 Mg C ha(-1), which is consistent with the global average of mangrove C density at similar latitudes, but higher than the average C density in terrestrial forests in China. Our results suggest that C storage in mangroves can be increased by selecting high C-density species for afforestation and stand improvement, and even more by increasing the mangrove area. The information gained in this study will facilitate policy decisions concerning the restoration of mangrove forests in China. PMID:24374165

  10. Increasing organic carbon stocks in Swedish agricultural soils due to unexpected socio-economic drivers

    Science.gov (United States)

    Poeplau, Christopher; Bolinder, Martin A.; Eriksson, Jan O.; Lundblad, Mattias; Kätterer, Thomas

    2015-04-01

    Management changes can induce significant alterations of soil organic carbon (SOC) stocks. Including trends in SOC within a certain land-use category can thus strongly influence the annual national inventory reports for greenhouse gas emissions. In 2013, the European Union has therefore decided that all member states shall report the evolvement of SOC within agricultural soils to increase the incentives to mitigate climate change by improving the management of those soils. Here, we present the country and county-wise SOC trends in Swedish agricultural mineral soils on the basis of three soil inventories conducted between 1988 and 2013. In the past two decades, the average topsoil (0-20 cm) SOC content of the whole country increased from 2.48% to 2.67% representing a relative change of 7.7% or 0.38% yr-1. This is in contrast to trends observed in neighboring countries such as Norway and Finland. We attributed this positive SOC trend to the increasing cultivation of leys throughout the country. Indeed, the below-ground carbon input of perennial grasses is up to fourfold as compared to cereals, which leads to a significant soil carbon sequestration potential under cropping systems with ley. The increase in ley proportion was significantly correlated to the increase in horse population in each county (R2=0.71), which has more than doubled in the past three decades. Due to subsidies introduced in the early 1990s, the area as long-term set-aside land (mostly old leys) also contributed to an increase in leys. This discloses the strong impact of rather local socio-economic trends on soil carbon storage, which also need to be considered in larger-scale model applications. This database is used in the continuous validation process of the Swedish national system for reporting changes in SOC stocks.

  11. Investigating cultural influences on investment process in stock exchange

    Directory of Open Access Journals (Sweden)

    Shamsodin Nazemi

    2012-09-01

    Full Text Available Cultural variety is a behavioral characteristic of investors and evaluating the cultural influences in the area of financial management on the decisions of investors plays an important role. In fact, different behaviors and decisions are required in various cultures facing the prices, price fluctuations and important or non-important published news of portfolio. In this paper, a questionnaire was designed including 22 cultural items in three criteria of values, facilities and behavior in order to measure the cultural factors affecting investment in stock exchange. Experts’ comments were used on the design of items and quintet Likert spectrum was applied for the answers. Structural equation modeling, or multivariable analysis with latent variables, is a comprehensive statistical approach for testing the hypotheses about relationships between observed and latent variables. Such analyzes have been done by LISREL software and the results showed that there was a significant relationship between investment and its triple factors and also between the items and triple factors affecting on investment.

  12. Organic carbon stock in topsoil of Jiangsu Province, China, and the recent trend of carbon sequestration

    Institute of Scientific and Technical Information of China (English)

    PAN Gen-xing; LI Lian-qing; ZHANG Qi; WANG Xu-kui; SUN Xing-bin; XU Xiao-bo; JIANG Ding-an

    2005-01-01

    Data collection of soil organic carbon(SOC) of 154 soil series of Jiangsu, China from the second provincial soil survey and of recent changes in SOC from a number of field pilot experiments across the province were collected. Statistical analysis of SOC contents and soil properties related to organic carbon storage were performed. The provincial total topsoil SOC stock was estimated to be 0.1 Pg with an extended pool of 0.4 Pg taking soil depth of 1 m, being relatively small compared to its total land area of 101700 km2 . One quarter of this topsoil stock was found in the soils of the Taihu Lake region that occupied 1/6 of the provincial arable area. Paddy soils accounted for over 50% of this stock in terms of SOC distribution among the soil types in the province. Experimental data from experimental farms widely distributed in the province showed that SOC storage increased consistently over the last 20 years despite a previously reported decreasing tendency during the period between 1950-1970. The evidence indicated that agricultural management practices such as irrigation, straw return and rotation of upland crops with rice or wheat crops contributed significantly to the increase in SOC storage. The annual carbon sequestration rate in the soils was in the range of 0.3-3.5 tC/( hm2 · a), depending on cropping systems and other agricultural practices. Thus, the agricultural production in the province, despite the high input, could serve as one of the practical methods to mitigate the increasing air CO2.

  13. INFLUENCE THE STOCKS ON YIELD AND QUALITY OF GRAPES AND ALIGOTE WINE

    Directory of Open Access Journals (Sweden)

    Chausov V. M.

    2016-01-01

    Full Text Available The article presents results of the six-year study of the effect of stocks Riparia × Rupestris 101-14 and Berlandieri × Riparia Kober 5BB on yield, quality of grapes and Aligote wine in the central zone of the Krasnodar region. Effect of stock on scion strongly depends on the annual weather conditions. In a given year, there is a stock better adapted to the weather conditions. Stocks of Riparia × Rupestris 101-14 increase winter hardiness, and the stock Berlandieri × Riparia Kober 5BB - drought-resistant varieties of Aligote. On average, during six years the stock has not been resulted in significant differences between the percentages of developed into shoots buds and fertile shoots shown in the coefficients of fruiting and fruitbearing shoots of Aligote. Among all the influencing factors, the degree of influence of stocks on the percentage of buds have evolved to 16,4 %, by the percentage of productive shoots 19,8 %, a factor of the fruiting shoots and fruitfulness of 3,9 % and 2,7 %, respectively. Some differences in forming of generative organs of wintering buds along the fruiting twig under the influence of stocks do not lead to the significant difference in biological terms of fruiting varieties in the whole piece. On average, six years of significant differences in the influence of rootstocks on the number of berries in bunches, hundred berries weight, an average weight of bunches and yield is not defined - the degree of influence of stocks on mentioned indicators is 0,1-9,7 %. A significant impact of stocks on the dynamics of sugar accumulation in berries has not been discovered. The degree of influence of stocks onto the final sugar content and acidity of berries is 2.9 and 1.0%, respectively. The wine produced from Aligote berries on a stock Riparia × Rupestris 101-14 has the better tasting score than on the stock Berlandieri × Riparia Kober 5BB (7.9 and 7.8 points, respect vely. The main influence on fruiting of the variety

  14. Geo-pedological control of soil organic carbon and nitrogen stocks at the landscape scale

    Science.gov (United States)

    Barré, Pierre; Durand, Hermine; Chenu, Claire; Meunier, Patrick; Montagne, David; Castel, Géraldine; Billiou, Daniel; Cécillon, Lauric

    2015-04-01

    Geo-pedology, here defined as soil type (or Reference Soil Group) and parent material, can have a major impact on ecosystem (vegetation and soil) functioning. Geo-pedology can therefore deeply influence soil organic matter (SOM) stock. Nonetheless, the effect of geo-pedology on soil organic C (SOC) and N stocks has seldom been investigated. Indeed, factors known to influence SOM stocks such as land use and climate frequently co-vary with geo-pedology, so that testing the influence on SOM stocks of the factor "geo-pedology" alone is challenging. In this work, we studied SOM stocks of forest and cropland soils in a small landscape (17 km²) of the Paris basin (AgroParisTech domain, Thiverval-Grignon, France). We collected soil samples (0-30 cm) in 50 forest and cropland plots, located in five geo-pedological contexts: Luvisols developed on loess deposit, Cambisols developed on hard limestone, Cambisols developed on shelly limestone, Cambisols developed on chalk and Cambisols developed on calcareous clay deposits. We then determined SOM stocks (organic C and total N) and SOM distribution across different particle size fractions (coarse sand, fine sand and silt-clay). As expected, SOC stocks were much higher in forests (~ 83 tC ha-1) than in cultivated soils (~ 49 tC ha-1). Interestingly, Cambisols had higher SOC stocks than Luvisols (69 vs 56 tC ha-1) and the difference between SOC stocks in forest and cultivated soils was much higher for Cambisols compared to Luvisols. Within Cambisols, parent material did not influence SOC stocks but the interaction between parent material and land use was significant, indicating that the effect of land use on SOC stocks was modulated by parent material. Similar trends were observed for soil N stocks. Conversely, soil type and parent material did not control SOM distribution in soil size fractions, while forest soils showed a higher distribution of SOC and N in the sand-size fraction than cropland soils. Overall, our study evidenced

  15. Carbon stock in Kolli forests, Eastern Ghats (India) with emphasis on aboveground biomass, litter, woody debris and soils

    OpenAIRE

    Mohanraj R; Saravanan J; Dhanakumar S

    2011-01-01

    The efficacy of tropical forest sinks in India continues to diminish in spite of several conservation efforts carried out at both governmental and non-governmental level. Lack of proper periodical and complete spatial inventory of carbon stock in India is a disturbing aspect at this aim. Carbon stock assessments are available only for few patches of Western Ghats of India, while assessment is almost negligible for Eastern Ghats. This paper focuses on estimation of existing carbon stock in the...

  16. Spatial variability of soil carbon stock in the Urucu river basin, Central Amazon-Brazil

    International Nuclear Information System (INIS)

    The Amazon Forest plays a major role in C sequestration and release. However, few regional estimates of soil organic carbon (SOC) stock in this ecoregion exist. One of the barriers to improve SOC estimates is the lack of recent soil data at high spatial resolution, which hampers the application of new methods for mapping SOC stock. The aims of this work were: (i) to quantify SOC stock under undisturbed vegetation for the 0–30 and the 0–100 cm under Amazon Forest; (ii) to correlate the SOC stock with soil mapping units and relief attributes and (iii) to evaluate three geostatistical techniques to generate maps of SOC stock (ordinary, isotopic and heterotopic cokriging). The study site is located in the Central region of Amazon State, Brazil. The soil survey covered the study site that has an area of 80 km2 and resulted in a 1:10,000 soil map. It consisted of 315 field observations (96 complete soil profiles and 219 boreholes). SOC stock was calculated by summing C stocks by horizon, determined as a product of BD, SOC and the horizon thickness. For each one of the 315 soil observations, relief attributes were derived from a topographic map to understand SOC dynamics. The SOC stocks across 30 and 100 cm soil depth were 3.28 and 7.32 kg C m−2, respectively, which is, 34 and 16%, lower than other studies. The SOC stock is higher in soils developed in relief forms exhibiting well-drained soils, which are covered by Upland Dense Tropical Rainforest. Only SOC stock in the upper 100 cm exhibited spatial dependence allowing the generation of spatial variability maps based on spatial (co)-regionalization. The CTI was inversely correlated with SOC stock and was the only auxiliary variable feasible to be used in cokriging interpolation. The heterotopic cokriging presented the best performance for mapping SOC stock. - Highlights: • The SOC stocks across 30 and 100 cm depth were 3.28 and 7.32 kg C m−2, respectively. • SOC stocks were 34 and 16%, respectively, lower

  17. Spatial variability of soil carbon stock in the Urucu river basin, Central Amazon-Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Ceddia, Marcos Bacis, E-mail: marcosceddia@gmail.com [Department of Soil, Institute of Agronomy, Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropédica, RJ 23890-000 (Brazil); Villela, André Luis Oliveira [Colégio Técnico da UFRRJ, RJ, Seropédica 23890-000 (Brazil); Pinheiro, Érika Flávia Machado [Department of Soil, Institute of Agronomy, Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropédica, RJ 23890-000 (Brazil); Wendroth, Ole [Department of Plant & Soil Sciences, University of Kentucky, College of Agriculture, Lexington, KY (United States)

    2015-09-01

    The Amazon Forest plays a major role in C sequestration and release. However, few regional estimates of soil organic carbon (SOC) stock in this ecoregion exist. One of the barriers to improve SOC estimates is the lack of recent soil data at high spatial resolution, which hampers the application of new methods for mapping SOC stock. The aims of this work were: (i) to quantify SOC stock under undisturbed vegetation for the 0–30 and the 0–100 cm under Amazon Forest; (ii) to correlate the SOC stock with soil mapping units and relief attributes and (iii) to evaluate three geostatistical techniques to generate maps of SOC stock (ordinary, isotopic and heterotopic cokriging). The study site is located in the Central region of Amazon State, Brazil. The soil survey covered the study site that has an area of 80 km{sup 2} and resulted in a 1:10,000 soil map. It consisted of 315 field observations (96 complete soil profiles and 219 boreholes). SOC stock was calculated by summing C stocks by horizon, determined as a product of BD, SOC and the horizon thickness. For each one of the 315 soil observations, relief attributes were derived from a topographic map to understand SOC dynamics. The SOC stocks across 30 and 100 cm soil depth were 3.28 and 7.32 kg C m{sup −2}, respectively, which is, 34 and 16%, lower than other studies. The SOC stock is higher in soils developed in relief forms exhibiting well-drained soils, which are covered by Upland Dense Tropical Rainforest. Only SOC stock in the upper 100 cm exhibited spatial dependence allowing the generation of spatial variability maps based on spatial (co)-regionalization. The CTI was inversely correlated with SOC stock and was the only auxiliary variable feasible to be used in cokriging interpolation. The heterotopic cokriging presented the best performance for mapping SOC stock. - Highlights: • The SOC stocks across 30 and 100 cm depth were 3.28 and 7.32 kg C m{sup −2}, respectively. • SOC stocks were 34 and 16

  18. Carbon Stocking in the Natural Forests – The Case of Malaysia

    Directory of Open Access Journals (Sweden)

    Jegatheswaran RATNASINGAM

    2015-04-01

    Full Text Available Forested land in the world is about 28% of the global land area, accounting for 80% of the terrestrial carbon stored as biomass and soil organic carbon. Human activities, namely fossil fuel combustion and deforestation resulted in anthropogenic emissions into the atmosphere. Deforestation is being focused in this study in view of the role of forests as carbon stocks. Carbon is normally referred to as biomass of the tree. Several studies revealed that carbon is mostly sequestered in the aboveground part of biomass. As Southeast Asia has the highest level of deforestation, this study focused on observing carbon stocks in Malaysian forests. The conducted estimation of forest carbon stocks reveals carbon stock increment owing to the increment in the forested land. Yet, the forest transition process necessary for expanding the areas of forested land appears to be difficult to achieve. The economic development in the agricultural sector, land conversion for industrialization and settlement, expansion of wood-based industry and employment opportunities in the wood-based sector may hamper forest transition.

  19. Using basal area to estimate aboveground carbon stocks in forests: La Primavera Biosphere's Reserve, Mexico

    NARCIS (Netherlands)

    Balderas Torres, A.; Lovett, J.C.

    2012-01-01

    Increasing use of woody plants for greenhouse gas mitigation has led to demand for rapid, cost-effective estimation of forest carbon stocks. Bole diameter is readily measured and basal area can be correlated to biomass and carbon through application of allometric equations. We explore different form

  20. Temporal dynamics and sPatial variations of forest vegetation carbon stock in Liaoning Province, China

    Institute of Scientific and Technical Information of China (English)

    LI Qing; TANG Li-Na; REN Yin

    2011-01-01

    There are many uncertainties in the estimation of forest carbon sequestration in China,especially in Liaoning Province where various forest inventory data have not been fully utilized.By using forest inventory data,we estimated forest vegetation carbon stock of Liaoning Province between 1993 and 2005.Results showed that forest biomass carbon stock increased from 68.91 Tg C in 1993 to 97.51 Tg C in 2005,whereas mean carbon density increased from 18.48 Mg.ha-1 C to 22.33 Mg·ha-1 C.The carbon storage of young- and middle-aged forests increased by 22.1 Tg C and 5.95 Tg C,but that of mature forests has decreased by 0.25 Tg C.The carbon stock and density of forests in Liaoning Province varied greatly in space:larger carbon storage and higher carbon density were primarily found in the east area.The spatial distribution of carbon density was determined by many factors,of which human activities played an important role.The forests in Liauning Province played a positive role as a sink of atmospheric carbon dioxide.The carbun fixation ability of forests in this area was primarily derived from forest plantation and the total forest carbon sequestration can be enhanced by expanding young- and middle-aged forests.

  1. Imputing forest carbon stock estimates from inventory plots to a nationally continuous coverage

    OpenAIRE

    Wilson Barry Tyler; Woodall Christopher W; Griffith Douglas M

    2013-01-01

    Abstract The U.S. has been providing national-scale estimates of forest carbon (C) stocks and stock change to meet United Nations Framework Convention on Climate Change (UNFCCC) reporting requirements for years. Although these currently are provided as national estimates by pool and year to meet greenhouse gas monitoring requirements, there is growing need to disaggregate these estimates to finer scales to enable strategic forest management and monitoring activities focused on various ecosyst...

  2. A Framework for Assessing Global Change Risks to Forest Carbon Stocks in the United States

    OpenAIRE

    Christopher W Woodall; Grant M Domke; Riley, Karin L.; Christopher M Oswalt; Crocker, Susan J.; Yohe, Gary W.

    2013-01-01

    Among terrestrial environments, forests are not only the largest long-term sink of atmospheric carbon (C), but are also susceptible to global change themselves, with potential consequences including alterations of C cycles and potential C emission. To inform global change risk assessment of forest C across large spatial/temporal scales, this study constructed and evaluated a basic risk framework which combined the magnitude of C stocks and their associated probability of stock change in the c...

  3. Quantifying the Spatial-temporal Variability in Carbon Stocks in a California Vineyard

    OpenAIRE

    Morande, Jorge Andres

    2015-01-01

    Quantifying terrestrial carbon (C) stocks in vineyards represents an important opportunity for estimating C sequestration in perennial cropping systems. Considering ~230,000 ha in California (8.2% of total land cultivated in CA) are dedicated to wine grape production, annual C capture and storage in woody biomass is substantial. In this study, destructive sampling was used to measure C stocks in the woody biomass of a 15-year-old Cabernet Sauvignon vines from a California Northern San Joaquin...

  4. Estimating litter carbon stocks on forest land in the United States.

    Science.gov (United States)

    Domke, Grant M; Perry, Charles H; Walters, Brian F; Woodall, Christopher W; Russell, Matthew B; Smith, James E

    2016-07-01

    Forest ecosystems are the largest terrestrial carbon sink on earth, with more than half of their net primary production moving to the soil via the decomposition of litter biomass. Therefore, changes in the litter carbon (C) pool have important implications for global carbon budgets and carbon emissions reduction targets and negotiations. Litter accounts for an estimated 5% of all forest ecosystem carbon stocks worldwide. Given the cost and time required to measure litter attributes, many of the signatory nations to the United Nations Framework Convention on Climate Change report estimates of litter carbon stocks and stock changes using default values from the Intergovernmental Panel on Climate Change or country-specific models. In the United States, the country-specific model used to predict litter C stocks is sensitive to attributes on each plot in the national forest inventory, but these predictions are not associated with the litter samples collected over the last decade in the national forest inventory. Here we present, for the first time, estimates of litter carbon obtained using more than 5000 field measurements from the national forest inventory of the United States. The field-based estimates mark a 44% reduction (2081±77Tg) in litter carbon stocks nationally when compared to country-specific model predictions reported in previous United Framework Convention on Climate Change submissions. Our work suggests that Intergovernmental Panel on Climate Change defaults and country-specific models used to estimate litter carbon in temperate forest ecosystems may grossly overestimate the contribution of this pool in national carbon budgets. PMID:27017077

  5. On the rebound: soil organic carbon stocks can bounce back to near forest levels when agroforests replace agriculture in southern India

    Science.gov (United States)

    Hombegowda, H. C.; van Straaten, O.; Köhler, M.; Hölscher, D.

    2016-01-01

    Tropical agroforestry has an enormous potential to sequester carbon while simultaneously producing agricultural yields and tree products. The amount of soil organic carbon (SOC) sequestered is influenced by the type of the agroforestry system established, the soil and climatic conditions, and management. In this regional-scale study, we utilized a chronosequence approach to investigate how SOC stocks changed when the original forests are converted to agriculture, and then subsequently to four different agroforestry systems (AFSs): home garden, coffee, coconut and mango. In total we established 224 plots in 56 plot clusters across 4 climate zones in southern India. Each plot cluster consisted of four plots: a natural forest reference, an agriculture reference and two of the same AFS types of two ages (30-60 years and > 60 years). The conversion of forest to agriculture resulted in a large loss the original SOC stock (50-61 %) in the top meter of soil depending on the climate zone. The establishment of home garden and coffee AFSs on agriculture land caused SOC stocks to rebound to near forest levels, while in mango and coconut AFSs the SOC stock increased only slightly above the agriculture SOC stock. The most important variable regulating SOC stocks and its changes was tree basal area, possibly indicative of organic matter inputs. Furthermore, climatic variables such as temperature and precipitation, and soil variables such as clay fraction and soil pH were likewise all important regulators of SOC and SOC stock changes. Lastly, we found a strong correlation between tree species diversity in home garden and coffee AFSs and SOC stocks, highlighting possibilities to increase carbon stocks by proper tree species assemblies.

  6. Quantification of parameters controlling the carbon stocks in German agricultural soils

    Science.gov (United States)

    Vos, Cora; Don, Axel; Freibauer, Annette; Heidkamp, Arne; Prietz, Roland

    2016-04-01

    Within the framework of UNFCCC, Germany is obligated to report on its greenhouse gas emissions from soils. This also includes the emissions in the agricultural sector. Changes in soil carbon stocks are a major source of CO2 that need to be reported. Until now there are only regional inventories of the soil carbon stocks in the agricultural sector while for the forestry sector a repeated national inventory exists. In order to report on changes in soil carbon stocks in agricultural soils, a consistent, representative and quantitative dataset of agricultural soil properties, especially on carbon stocks and management data is necessary. In the course of the German Agricultural Soil Inventory 3109 agricultural sites are examined. Up to January 2016, 2450 sites were sampled. The sites are sampled in five depth increments and all samples are analyzed in the same laboratory. Of the sampled sites the laboratory analyses are completed for 1312 sites. The samples of all depth increments were analyzed for their texture, bulk density, pH, electric conductivity, stone and root content, organic and inorganic carbon content and nitrogen content. The data are coupled with management data covering the past ten years and with climate data. They are analyzed with multivariate statistical techniques (e.g. mixed effects models, additive models, random forest) to quantify the parameters that control the carbon stocks in German agricultural soils. First descriptive results show that the mean soil carbon stocks down to a depth of 100 cm are 126.1 t ha‑1 (range 8.9-1158.9 t ha‑1). The mean stocks only for croplands are 102.6 t ha‑1 (range 8.9-1158.9 t ha‑1), while for grasslands the mean stock is 184.1 t ha‑1 (range 19.4-937.8 t ha‑1). In total the soil scientists found a surprisingly high proportion of disturbed and unusual soil profiles, indicating intensive human modifications of agricultural soils through e.g. deep ploughing. The data set of the German Agricultural Soil

  7. Estimating Forest Carbon Stock Dynamics from Forest Inventories, Disturbance Data and Simulation Models: An Integrated Analysis for British Columbia

    Science.gov (United States)

    Kurz, W. A.; Beukema, S. J.; Robinson, D. C.; Apps, M. J.

    2001-12-01

    Forest inventories and growth and yield projection systems are an integral part of modern forest management. This information is commonly used for the long-term planning of annual allowable cuts and timber supply analysis. A strategy for the use of such information in a comprehensive, regional carbon budget model was developed and implemented for British Columbia, Canada. Data readily accessible from forest information systems include the area, stratification and attributes (including merchantable volume) of forests. Growth and yield tables or empirical models provide the required information on stand dynamics. Disturbance statistics (harvest, fire, insects) describe the dynamics of the forest area. Temporary and permanent sample plots provide millions of tree measurements that were used in the conversion of volume to biomass estimates. Methods previously developed for the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS2) were used to calculate belowground biomass and to establish the various dead organic matter pools. Inventory data are nearly complete, except for a small portion of the total forest area. Land-use change statistics are available for forest roads, but not yet for other causes of land-use change. A modified version of the CBM-CFS2 was used to calculate C stocks and stock changes for the period 2000 to 2032. Results indicate that ecosystem C stocks in the timber harvest land base are changing very little, with between-year variability of - 20 to + 20 Tg C / year. In contrast, ecosystem C stocks in the non-timber harvest land base are increasing at a rate of about 100 Tg C / year, largely because of the absence of harvesting and the assumed rates of future fire and insect disturbances, which could be the result of protection efforts. Actual disturbance rates, observed in future years, could have large impacts on C stock changes. Annual changes in C stocks will also be influenced by climate variability. Growth and yield models predict

  8. Digital Mapping of Soil Organic Carbon Contents and Stocks in Denmark

    DEFF Research Database (Denmark)

    Adhikari, Kabindra; Hartemink, Alfred E.; Minasny, Budiman;

    2014-01-01

    Estimation of carbon contents and stocks are important for carbon sequestration, greenhouse gas emissions and national carbon balance inventories. For Denmark, we modeled the vertical distribution of soil organic carbon (SOC) and bulk density, and mapped its spatial distribution at five standard...... the top 1 m there was 120 t SOC ha21. In total, the soils stored approximately 570 Tg C within the top 1 m. The soils under agriculture had the highest amount of carbon (444 Tg) followed by forest and semi-natural vegetation that contributed 11% of the total SOC stock. More than 60% of the total SOC...... and high-resolution maps could be used for future soil carbon assessment and inventories....

  9. Profiles of carbon stocks in forest, reforestation and agricultural land, Northern Thailand

    Institute of Scientific and Technical Information of China (English)

    P. Pibumrung; N. Gajaseni; A. Popan

    2008-01-01

    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.

  10. Carbon stocks of tropical coastal wetlands within the karstic landscape of the Mexican Caribbean.

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Adame

    Full Text Available Coastal wetlands can have exceptionally large carbon (C stocks and their protection and restoration would constitute an effective mitigation strategy to climate change. Inclusion of coastal ecosystems in mitigation strategies requires quantification of carbon stocks in order to calculate emissions or sequestration through time. In this study, we quantified the ecosystem C stocks of coastal wetlands of the Sian Ka'an Biosphere Reserve (SKBR in the Yucatan Peninsula, Mexico. We stratified the SKBR into different vegetation types (tall, medium and dwarf mangroves, and marshes, and examined relationships of environmental variables with C stocks. At nine sites within SKBR, we quantified ecosystem C stocks through measurement of above and belowground biomass, downed wood, and soil C. Additionally, we measured nitrogen (N and phosphorus (P from the soil and interstitial salinity. Tall mangroves had the highest C stocks (987±338 Mg ha(-1 followed by medium mangroves (623±41 Mg ha(-1, dwarf mangroves (381±52 Mg ha(-1 and marshes (177±73 Mg ha(-1. At all sites, soil C comprised the majority of the ecosystem C stocks (78-99%. Highest C stocks were measured in soils that were relatively low in salinity, high in P and low in N∶P, suggesting that P limits C sequestration and accumulation potential. In this karstic area, coastal wetlands, especially mangroves, are important C stocks. At the landscape scale, the coastal wetlands of Sian Ka'an covering ≈172,176 ha may store 43.2 to 58.0 million Mg of C.

  11. Carbon stocks of tropical coastal wetlands within the karstic landscape of the Mexican Caribbean.

    Science.gov (United States)

    Adame, Maria Fernanda; Kauffman, J Boone; Medina, Israel; Gamboa, Julieta N; Torres, Olmo; Caamal, Juan P; Reza, Miriam; Herrera-Silveira, Jorge A

    2013-01-01

    Coastal wetlands can have exceptionally large carbon (C) stocks and their protection and restoration would constitute an effective mitigation strategy to climate change. Inclusion of coastal ecosystems in mitigation strategies requires quantification of carbon stocks in order to calculate emissions or sequestration through time. In this study, we quantified the ecosystem C stocks of coastal wetlands of the Sian Ka'an Biosphere Reserve (SKBR) in the Yucatan Peninsula, Mexico. We stratified the SKBR into different vegetation types (tall, medium and dwarf mangroves, and marshes), and examined relationships of environmental variables with C stocks. At nine sites within SKBR, we quantified ecosystem C stocks through measurement of above and belowground biomass, downed wood, and soil C. Additionally, we measured nitrogen (N) and phosphorus (P) from the soil and interstitial salinity. Tall mangroves had the highest C stocks (987±338 Mg ha(-1)) followed by medium mangroves (623±41 Mg ha(-1)), dwarf mangroves (381±52 Mg ha(-1)) and marshes (177±73 Mg ha(-1)). At all sites, soil C comprised the majority of the ecosystem C stocks (78-99%). Highest C stocks were measured in soils that were relatively low in salinity, high in P and low in N∶P, suggesting that P limits C sequestration and accumulation potential. In this karstic area, coastal wetlands, especially mangroves, are important C stocks. At the landscape scale, the coastal wetlands of Sian Ka'an covering ≈172,176 ha may store 43.2 to 58.0 million Mg of C. PMID:23457583

  12. Assessment of soil organic carbon stocks under future climate and land cover changes in Europe.

    Science.gov (United States)

    Yigini, Yusuf; Panagos, Panos

    2016-07-01

    Soil organic carbon plays an important role in the carbon cycling of terrestrial ecosystems, variations in soil organic carbon stocks are very important for the ecosystem. In this study, a geostatistical model was used for predicting current and future soil organic carbon (SOC) stocks in Europe. The first phase of the study predicts current soil organic carbon content by using stepwise multiple linear regression and ordinary kriging and the second phase of the study projects the soil organic carbon to the near future (2050) by using a set of environmental predictors. We demonstrate here an approach to predict present and future soil organic carbon stocks by using climate, land cover, terrain and soil data and their projections. The covariates were selected for their role in the carbon cycle and their availability for the future model. The regression-kriging as a base model is predicting current SOC stocks in Europe by using a set of covariates and dense SOC measurements coming from LUCAS Soil Database. The base model delivers coefficients for each of the covariates to the future model. The overall model produced soil organic carbon maps which reflect the present and the future predictions (2050) based on climate and land cover projections. The data of the present climate conditions (long-term average (1950-2000)) and the future projections for 2050 were obtained from WorldClim data portal. The future climate projections are the recent climate projections mentioned in the Fifth Assessment IPCC report. These projections were extracted from the global climate models (GCMs) for four representative concentration pathways (RCPs). The results suggest an overall increase in SOC stocks by 2050 in Europe (EU26) under all climate and land cover scenarios, but the extent of the increase varies between the climate model and emissions scenarios. PMID:27082446

  13. Analysis of Terrestrial Carbon Stocks in a Small Catchment of Northeastern Siberia

    Science.gov (United States)

    Heard, K.; Natali, S.; Bunn, A. G.; Loranty, M. M.; Kholodov, A. L.; Schade, J. D.; Berner, L. T.; Spektor, V.; Zimov, N.; Alexander, H. D.

    2015-12-01

    As arctic terrestrial ecosystems comprise about one-third of the global terrestrial ecosystem carbon total, understanding arctic carbon cycling and the feedback of terrestrial carbon pools to accelerated warming is an issue of global concern. For this research, we examined above- and belowground carbon stocks in a larch-dominated catchment underlain by yedoma and located within the Kolyma River watershed in northeastern Siberia. We quantified carbon stocks in vegetation, active layer, and permafrost, and we assessed the correlation between plant and active layer carbon pools and four environmental correlates — slope, solar insolation, canopy density, and leaf area index ­— at 20 sites. Carbon in the active layer was approximately four times greater than aboveground carbon pools (972 g C m-2), and belowground carbon to 1 m depth was approximately 18 times greater than aboveground carbon pools. Canopy density and slope had a robust positive association with aboveground carbon pools, and soil moisture was positively related to %C in organic, thawed mineral and permafrost soil. Thaw depth was negatively correlated with moss cover and larch biomass, highlighting the importance of vegetation and surface characteristics on permafrost carbon vulnerability. These data suggest that landscape and ecosystem characteristics affect carbon accumulation and storage, but they also play an important role in stabilizing permafrost carbon pools.

  14. Carbon stock of oil palm plantations and tropical forests in Malaysia

    DEFF Research Database (Denmark)

    Kho, Lip Khoon; Jepsen, Martin Rudbeck

    2015-01-01

    In Malaysia, the main land change process is the establishment of oil palm plantations on logged-over forests and areas used for shifting cultivation, which is the traditional farming system. While standing carbon stocks of old-growth forest have been the focus of many studies, this is less the...... case for Malaysian fallow systems and oil palm plantations. Here, we collate and analyse Malaysian datasets on total carbon stocks for both above- and below-ground biomass. We review the current knowledge on standing carbon stocks of 1) different forest ecosystems, 2) areas subject to shifting...... cultivation (fallow forests) and 3) oil palm plantations. The forest ecosystems are classified by successional stage and edaphic conditions and represent samples along a forest succession continuum spanning pioneer species in shifting cultivation fallows to climax vegetation in old-growth forests. Total...

  15. Carbon stocks and soil sequestration rates of riverine mangroves and freshwater wetlands

    Science.gov (United States)

    Adame, M. F.; Santini, N. S.; Tovilla, C.; Vázquez-Lule, A.; Castro, L.

    2015-01-01

    Deforestation and degradation of wetlands are important causes of carbon dioxide emissions to the atmosphere. Accurate measurements of carbon (C) stocks and sequestration rates are needed for incorporating wetlands into conservation and restoration programs with the aim for preventing carbon emissions. Here, we assessed whole ecosystem C stocks (trees, soil and downed wood) and soil N stocks of riverine wetlands (mangroves, marshes and peat swamps) within La Encrucijada Biosphere Reserve in the Pacific coast of Mexico. We also estimated soil C sequestration rates of mangroves on the basis of soil accumulation. We hypothesized that riverine wetlands have large C stocks, and that upland mangroves have larger C and soil N stocks compared to lowland mangroves. Riverine wetlands had large C stocks with a mean of 784.5 ± 73.5 Mg C ha-1 for mangroves, 722.2 ± 83.4 Mg C ha-1 for peat swamps, and 336.5 ± 38.3 Mg C ha-1 for marshes. C stocks and soil N stocks were in general larger for upland (833.0 ± 7.2 Mg C ha-1; 26.4 ± 0.5 Mg N ha-1) compared to lowland mangroves (659.5 ± 18.6 Mg C ha-1; 13.8 ± 2.0 Mg N ha-1). Soil C sequestration values were 1.3 ± 0.2 Mg C ha-1 yr-1. The Reserve stores 32.5 Mtons of C or 119.3 Mtons of CO2, with mangroves sequestering (via soil accumulation) 27 762 ± 0.5 Mg C ha-1 every year.

  16. Carbon stocks and soil sequestration rates of riverine mangroves and freshwater wetlands

    Directory of Open Access Journals (Sweden)

    M. F. Adame

    2015-01-01

    Full Text Available Deforestation and degradation of wetlands are important causes of carbon dioxide emissions to the atmosphere. Accurate measurements of carbon (C stocks and sequestration rates are needed for incorporating wetlands into conservation and restoration programs with the aim for preventing carbon emissions. Here, we assessed whole ecosystem C stocks (trees, soil and downed wood and soil N stocks of riverine wetlands (mangroves, marshes and peat swamps within La Encrucijada Biosphere Reserve in the Pacific coast of Mexico. We also estimated soil C sequestration rates of mangroves on the basis of soil accumulation. We hypothesized that riverine wetlands have large C stocks, and that upland mangroves have larger C and soil N stocks compared to lowland mangroves. Riverine wetlands had large C stocks with a mean of 784.5 ± 73.5 Mg C ha-1 for mangroves, 722.2 ± 83.4 Mg C ha-1 for peat swamps, and 336.5 ± 38.3 Mg C ha-1 for marshes. C stocks and soil N stocks were in general larger for upland (833.0 ± 7.2 Mg C ha-1; 26.4 ± 0.5 Mg N ha-1 compared to lowland mangroves (659.5 ± 18.6 Mg C ha-1; 13.8 ± 2.0 Mg N ha-1. Soil C sequestration values were 1.3 ± 0.2 Mg C ha-1 yr-1. The Reserve stores 32.5 Mtons of C or 119.3 Mtons of CO2, with mangroves sequestering (via soil accumulation 27 762 ± 0.5 Mg C ha-1 every year.

  17. The Moderating Influence of Supermarket Satisfaction on Out-of-Stock Store Switching Behaviour

    DEFF Research Database (Denmark)

    Hansen, Torben; Beckmann, Suzanne C.; Solgaard, Hans Stubbe

    Consumer store switching behaviour – going to another store to buy an item that is out-of-stock is often considered to be associated with high brand loyalty in combination with low store loyalty, making a study of the causes for such behaviour highly important to both store and brand managers...... variables on out-of-stock store switching. The results indicate that whereas preferred supermarket satisfaction negatively moderates the relation between quality consciousness and out-of-stock store switching, preferred supermarket satisfaction positively moderates the relation between price consciousness...... and out-of-stock store switching. In addition, it is demonstrated that quality consciousness, price consciousness, and pre-planning propensity positively influence consumer out-of-stock store switching behaviour....

  18. Climate change mitigation by carbon stock - the case of semi-arid West Africa

    Science.gov (United States)

    Lykke, A. M.; Barfod, A. S.; Tinggaard Svendsen, G.; Greve, M.; Svenning, J.-C.

    2009-11-01

    Semi-arid West Africa has not been integrated into the afforestation/reforestation (AR) carbon market. Most projects implemented under the Clean Development Mechanism (CDM) have focused on carbon emission reductions from industry and energy consumption, whereas only few (only one in West Africa) have been certified for AR carbon sequestration. A proposed mechanism, Reducing Emissions from Deforestation and Degradation (REDD) to be discussed under COP15 aims to reduce emissions by conserving already existing forests. REDD has high potential for carbon stocking at low costs, but focuses primarily on rain forest countries and excludes semi-arid West Africa from the preliminary setup. African savannas have potential to store carbon in the present situation with degrading ecosystems and relatively low revenues from crops and cattle, especially if it is possible to combine carbon stocking with promotion of secondary crops such as food resources and traditional medicines harvested on a sustainable basis. Methods for modelling and mapping of potential carbon biomass are being developed, but are still in a preliminary state. Although economic benefits from the sale of carbon credits are likely to be limited, carbon stocking is an interesting option if additional benefits are considered such as improved food security and protection of biodiversity.

  19. Climate change mitigation by carbon stock - the case of semi-arid West Africa

    International Nuclear Information System (INIS)

    Semi-arid West Africa has not been integrated into the afforestation/reforestation (AR) carbon market. Most projects implemented under the Clean Development Mechanism (CDM) have focused on carbon emission reductions from industry and energy consumption, whereas only few (only one in West Africa) have been certified for AR carbon sequestration. A proposed mechanism, Reducing Emissions from Deforestation and Degradation (REDD) to be discussed under COP15 aims to reduce emissions by conserving already existing forests. REDD has high potential for carbon stocking at low costs, but focuses primarily on rain forest countries and excludes semi-arid West Africa from the preliminary setup. African savannas have potential to store carbon in the present situation with degrading ecosystems and relatively low revenues from crops and cattle, especially if it is possible to combine carbon stocking with promotion of secondary crops such as food resources and traditional medicines harvested on a sustainable basis. Methods for modelling and mapping of potential carbon biomass are being developed, but are still in a preliminary state. Although economic benefits from the sale of carbon credits are likely to be limited, carbon stocking is an interesting option if additional benefits are considered such as improved food security and protection of biodiversity.

  20. Wall-to-wall assessment of carbon stock and flux consequences of forest disturbances in the Pacific Northwest United States using remote sensing and forest inventory data

    Science.gov (United States)

    Gu, H.; Williams, C. A.; Collatz, G. J.; Masek, J. G.; Moisen, G.; Schleeweis, K.; Ghimire, B.; Zhao, F. A.; Huang, C.; Saatchi, S. S.

    2015-12-01

    Disturbances profoundly alter the structure and function of forests, imposing long lasting carbon legacies and strongly influencing rates of terrestrial carbon exchange with the atmosphere. Disturbance legacies vary across ecoregions, by forest types, and with disturbance severity and type. The complexity presents a significant challenge for observing and modeling carbon exchange, and hinders assessments of current and likely future states of the global carbon cycle. We demonstrate how carbon legacies vary following harvest, fire and bark beetle for forests in Pacific Norwest (PNW) United States, and how these processes influence carbon stocks and fluxes at pixel and regional scales. This study involves the use of satellite and aerial remote sensing products to characterize the frequency and severity of fire, harvest and insects over the past three decades. We use forest inventory data (FIA) to parameterize a carbon cycle model to represent post-disturbance carbon trajectories of carbon pools and fluxes for harvest, fire and bark beetle disturbances of varying severity across forest types and site productivity. We infer forest stand age and associated uncertainty based on maps of aboveground biomass, disturbance and forest types derived from remote sensing data, as well as carbon stock trajectories and stand productivity map derived from FIA. We then apply the group of carbon flux trajectories to the forest stand age map throughout the study area. Finally, we summarize the net carbon uptake as a consequence of disturbance and regrowth at pixel and regional scales. As such, this study represents a first demonstration of a spatially explicit assessment of carbon stock and flux responses to disturbances by linking remote sensing disturbance products, biomass maps and forest inventory data in a carbon cycle modeling framework. The methodology will be further applied across the conterminous US to provide a comprehensive forest carbon budget assessment.

  1. Sampling protocol recommendations for measuring soil organic carbon stocks in the tropics

    Science.gov (United States)

    van Straaten, Oliver; Veldkamp, Edzo; Corre, Marife D.

    2013-04-01

    In the tropics, there is an urgent need for cost effective sampling approaches to quantify soil organic carbon (SOC) changes associated with land-use change given the lack of reliable data. The tropics are especially important considering the high deforestation rates, the huge belowground carbon pool and the fast soil carbon turnover rates. In the framework of a pan-tropic (Peru, Cameroon and Indonesia) land-use change study, some highly relevant recommendations on the SOC stocks sampling approaches have emerged. In this study, where we focused on deeply weathered mineral soils, we quantified changes in SOC stock following land-use change (deforestation and subsequent establishment of other land-uses). We used a space-for-time substitution sampling approach, measured SOC stocks in the top three meters of soil and compared recently converted land-uses with adjacent reference forest plots. In each respective region we investigated the most predominant land-use trajectories. In total 157 plots were established across the three countries, where soil samples were taken to a depth of three meters from a central soil pit and from the topsoil (to 0.5m) from 12 pooled composite samples. Finding 1 - soil depth: despite the fact that the majority of SOC stock from the three meter profile is found below one meter depth (50 to 60 percent of total SOC stock), the significant changes in SOC were only measured in the top meter of soil, while the subsoil carbon stock remained relatively unchanged by the land-use conversion. The only exception was for older (>50 yrs) cacao plantations in Cameroon where significant decreases were found below one meter. Finding 2 - pooled composite samples taken across the plot provided more spatially representative estimates of SOC stocks than samples taken from the central soil pit.

  2. Forest carbon stocks and fluxes in physiographic zones of India

    OpenAIRE

    Sheikh Mehraj A; Kumar Munesh; Bussman Rainer W; Todaria NP

    2011-01-01

    Abstract Background Reducing carbon Emissions from Deforestation and Degradation (REDD+) is of central importance to combat climate change. Foremost among the challenges is quantifying nation's carbon emissions from deforestation and degradation, which requires information on forest carbon storage. Here we estimated carbon storage in India's forest biomass for the years 2003, 2005 and 2007 and the net flux caused by deforestation and degradation, between two assessment periods i.e., Assessmen...

  3. Mapping of soil organic carbon stocks for spatially explicit assessments of climate change mitigation potential

    International Nuclear Information System (INIS)

    Current methods for assessing soil organic carbon (SOC) stocks are generally not well suited for understanding variations in SOC stocks in landscapes. This is due to the tedious and time-consuming nature of the sampling methods most commonly used to collect bulk density cores, which limits repeatability across large areas, particularly where information is needed on the spatial dynamics of SOC stocks at scales relevant to management and for spatially explicit targeting of climate change mitigation options. In the current study, approaches were explored for (i) field-based estimates of SOC stocks and (ii) mapping of SOC stocks at moderate to high resolution on the basis of data from four widely contrasting ecosystems in East Africa. Estimated SOC stocks for 0–30 cm depth varied both within and between sites, with site averages ranging from 2 to 8 kg m−2. The differences in SOC stocks were determined in part by rainfall, but more importantly by sand content. Results also indicate that managing soil erosion is a key strategy for reducing SOC loss and hence in mitigation of climate change in these landscapes. Further, maps were developed on the basis of satellite image reflectance data with multiple R-squared values of 0.65 for the independent validation data set, showing variations in SOC stocks across these landscapes. These maps allow for spatially explicit targeting of potential climate change mitigation efforts through soil carbon sequestration, which is one option for climate change mitigation and adaptation. Further, the maps can be used to monitor the impacts of such mitigation efforts over time. (letter)

  4. The influence of environment on stock assessment : an approach with surplus production models

    OpenAIRE

    Fréon, Pierre

    1995-01-01

    Conventional global production models are not suitable for some stocks because fishing effort variations only explain only a small part of the total variability of annual catches. Often the residual variability originates from the influence of environmental phenomena, which affects either the abundance or the catchability of a stock from one year to the next. Therefore an additional environmental variable has been inserted into conventional models in order to improve their accuracy. These var...

  5. Estimation of soil organic carbon stocks and stock changes in Croatia (1980–2006) – use of national soil database and the Corine Land Cover

    OpenAIRE

    Pilaš, Ivan; Kušan, Vladimir; Medved, Ivan; MEDAK, JASNICA; Bakšić, Nikolina; Marjanović, Hrvoje

    2013-01-01

    Background and Purpose: In this study, estimation of soil organic carbon (SOC) stocks for the LULUCF categories is provided together with assessment of spatial and temporal trend of soil carbon density (SCD) for the 1980–2006 period in Croatia. Materials andMethods: Calculations of soil carbon stockswas based on data of soil organic carbon from the national (pedon) database of Croatian soils that consisted of 2351 soil profiles and Corine Land Cover inventories in 1980, 1990, 2000 a...

  6. Landscape patterns and soil organic carbon stocks in agricultural bocage landscapes

    Science.gov (United States)

    Viaud, Valérie; Lacoste, Marine; Michot, Didier; Walter, Christian

    2014-05-01

    Soil organic carbon (SOC) has a crucial impact on global carbon storage at world scale. SOC spatial variability is controlled by the landscape patterns resulting from the continuous interactions between the physical environment and the society. Natural and anthropogenic processes occurring and interplaying at the landscape scale, such as soil redistribution in the lateral and vertical dimensions by tillage and water erosion processes or spatial differentiation of land-use and land-management practices, strongly affect SOC dynamics. Inventories of SOC stocks, reflecting their spatial distribution, are thus key elements to develop relevant management strategies to improving carbon sequestration and mitigating climate change and soil degradation. This study aims to quantify SOC stocks and their spatial distribution in a 1,000-ha agricultural bocage landscape with dairy production as dominant farming system (Zone Atelier Armorique, LTER Europe, NW France). The site is characterized by high heterogeneity on short distance due to a high diversity of soils with varying waterlogging, soil parent material, topography, land-use and hedgerow density. SOC content and stocks were measured up to 105-cm depth in 200 sampling locations selected using conditioned Latin hypercube sampling. Additive sampling was designed to specifically explore SOC distribution near to hedges: 112 points were sampled at fixed distance on 14 transects perpendicular from hedges. We illustrate the heterogeneity of spatial and vertical distribution of SOC stocks at landscape scale, and quantify SOC stocks in the various landscape components. Using multivariate statistics, we discuss the variability and co-variability of existing spatial organization of cropping systems, environmental factors, and SOM stocks, over landscape. Ultimately, our results may contribute to improving regional or national digital soil mapping approaches, by considering the distribution of SOC stocks within each modeling unit and

  7. Climatic regions as an indicator of forest coarse and fine woody debris carbon stocks in the United States

    Directory of Open Access Journals (Sweden)

    Liknes Greg C

    2008-06-01

    Full Text Available Abstract Background Coarse and fine woody debris are substantial forest ecosystem carbon stocks; however, there is a lack of understanding how these detrital carbon stocks vary across forested landscapes. Because forest woody detritus production and decay rates may partially depend on climatic conditions, the accumulation of coarse and fine woody debris carbon stocks in forests may be correlated with climate. This study used a nationwide inventory of coarse and fine woody debris in the United States to examine how these carbon stocks vary by climatic regions and variables. Results Mean coarse and fine woody debris forest carbon stocks vary by Köppen's climatic regions across the United States. The highest carbon stocks were found in regions with cool summers while the lowest carbon stocks were found in arid desert/steppes or temperate humid regions. Coarse and fine woody debris carbon stocks were found to be positively correlated with available moisture and negatively correlated with maximum temperature. Conclusion It was concluded with only medium confidence that coarse and fine woody debris carbon stocks may be at risk of becoming net emitter of carbon under a global climate warming scenario as increases in coarse or fine woody debris production (sinks may be more than offset by increases in forest woody detritus decay rates (emission. Given the preliminary results of this study and the rather tenuous status of coarse and fine woody debris carbon stocks as either a source or sink of CO2, further research is suggested in the areas of forest detritus decay and production.

  8. Soil carbon under perennial pastures; benchmarking the influence of pasture age and management

    Science.gov (United States)

    Orgill, Susan E.; Spoljaric, Nancy; Kelly, Georgina

    2015-07-01

    This paper reports baseline soil carbon stocks from a field survey of 19 sites; 8 pairs/triplet in the Monaro region of New South Wales. Site comparisons were selected by the Monaro Farming Systems group to demonstrate the influence of land management on soil carbon, and included: nutrient management, liming, pasture age and cropping history. Soil carbon stocks varied with parent material and with land management. The fertilised (phosphorus) native perennial pasture had a greater stock of soil carbon compared with the unfertilised site; 46.8 vs 40.4 Mg.C.ha to 0.50 m. However, the introduced perennial pasture which had been limed had a lower stock of soil carbon compared with the unlimed site; 62.8 vs 66.7 Mg.C.ha to 0.50 m. There was a greater stock of soil carbon under two of the three younger (35 yr old) pastures. Cropped sites did not have lower soil carbon stocks at all sites; however, this survey was conducted after three years of above average annual rainfall and most sites had been cropped for less than three years. At all sites more than 20% of the total carbon stock to 0.50 m was in the 0.30 to 0.50 m soil layer highlighting the importance of considering this soil layer when investigating the implications of land management on soil carbon. Our baseline data indicates that nutrient management may increase soil carbon under perennial pastures and highlights the importance of perennial pastures for soil carbon sequestration regardless of age.

  9. A blue carbon soil database: Tidal wetland stocks for the US National Greenhouse Gas Inventory

    Science.gov (United States)

    Feagin, R. A.; Eriksson, M.; Hinson, A.; Najjar, R. G.; Kroeger, K. D.; Herrmann, M.; Holmquist, J. R.; Windham-Myers, L.; MacDonald, G. M.; Brown, L. N.; Bianchi, T. S.

    2015-12-01

    Coastal wetlands contain large reservoirs of carbon, and in 2015 the US National Greenhouse Gas Inventory began the work of placing blue carbon within the national regulatory context. The potential value of a wetland carbon stock, in relation to its location, soon could be influential in determining governmental policy and management activities, or in stimulating market-based CO2 sequestration projects. To meet the national need for high-resolution maps, a blue carbon stock database was developed linking National Wetlands Inventory datasets with the USDA Soil Survey Geographic Database. Users of the database can identify the economic potential for carbon conservation or restoration projects within specific estuarine basins, states, wetland types, physical parameters, and land management activities. The database is geared towards both national-level assessments and local-level inquiries. Spatial analysis of the stocks show high variance within individual estuarine basins, largely dependent on geomorphic position on the landscape, though there are continental scale trends to the carbon distribution as well. Future plans including linking this database with a sedimentary accretion database to predict carbon flux in US tidal wetlands.

  10. Dynamics of organic carbon stock of Estonian arable and grassland peat soils

    Science.gov (United States)

    Kauer, Karin; Tammik, Kerttu; Penu, Priit

    2016-04-01

    Peat soils represent globally a major reserve of soil organic carbon (SOC). Estimation of changes in SOC stocks is important for understanding soil carbon sequestration and dynamics of greenhouse gas emissions. The aim of this study was to estimate the SOC stock of Estonian agricultural peat soils and SOC stock change depending on land use type (arable land and long-term grasslands (over 5 years)). The soils were classified as Histosols according to WRB classification. Generally the arable land was used for growing cereals, oilseed rape, legumes and used as ley in crop rotation. The main technique of soil cultivation was ploughing. During 2002-2015 the soil samples of 0-20 cm soil layer (one average soil sample per 1-5 ha) were collected. The SOC content was measured by NIRS method. The SOC stock was calculated by assuming that soil mean bulk density is 0.3 g cm-3. The SOC stock change in arable land was estimated during 3-13 years (N=91) and in grassland 4-13 year (N=163). The average SOC content of peat soils varied from 150.6 to 549.0 mg g-1. The initial SOC stock of arable land was 271.3 t ha-1 and of grassland 269.3 t ha-1. The SOC stock declined in arable peat soils faster (-2.57 t ha-1 y-1) compared to the changes in grassland peat soils (-0.67 t ha-1 y-1). According to the length of the study period the SOC stock change per year varied from -5.14 to 6.64 t ha-1 y-1 in grasslands and from -14.78 to 0.83 t ha-1 y-1 in arable land, although there was no clear relationship between the SOC stock change and the length of the study period. More detailed information about the properties of agricultural land and land use history is needed to analyse the causes of the SOC stock changes in agricultural peat soils. However, from the current research we can conclude that the SOC stock of arable and grassland peat soils is declining during the cultivation. These decreases are important to specify when considering the role of peat soils in atmospheric greenhouse gas

  11. Total and pyrogenic carbon stocks in black spruce forest floors from eastern Canada

    Science.gov (United States)

    Soucemarianadin, Laure; Quideau, Sylvie; MacKenzie, M. Derek; Munson, Alison; Boiffin, Juliette; Bernard, Guy; Wasylishen, Roderick

    2016-04-01

    In boreal forests, pyrogenic carbon (PyC), a by-product of recurrent wildfires, is an important component of the global soil C pool, although precise assessment of boreal PyC stock is scarce. In this study including 14 fire sites spreading over 600 km in the Quebec province, our aim was to better estimate total C stock and PyC stock in forest floors of Eastern Canada boreal forests. We also investigated the environmental conditions controlling the stocks and characterized the composition of the various forest floor layers. We analyzed the forest floor samples that were collected from mesic black spruce sites recently affected by fire (3-5 years) using elemental analysis and solid state 13C nuclear magnetic resonance (NMR) spectroscopy. PyC content was further estimated using a molecular mixing model on the 13C NMR data. Total C stock in forest floors averaged 5.7 ± 2.9 kg C/m2 and PyC stock 0.6 ± 0.3 kg C/m2. Total C stock was under control of the position in the landscape, with a greater accumulation of organic material on northern aspects and lower slope positions. In addition, total stock was significantly higher in spruce-dominated forest floors than in stands where jack pine was dominant. The PyC stock was significantly related to the atomic H/C ratio (R2 = 0.84) of the different organic layers. 13C NMR spectroscopy revealed a large increase in aromatic carbon in the deepest forest floor layer (humified H horizon) at the organic-mineral soil interface. The majority of the PyC stock was located in this horizon and had been formed during past high severity fires rather than during the most recent fire event. Conversely, the superficial "fresh" PyC layer, produced by early-season wildfires in 2005-2007, had NMR spectra fairly similar to unburned forest floors and comparatively low PyC stocks.

  12. Organic carbon stocks and sequestration rates of forest soils in Germany.

    Science.gov (United States)

    Grüneberg, Erik; Ziche, Daniel; Wellbrock, Nicole

    2014-08-01

    The National Forest Soil Inventory (NFSI) provides the Greenhouse Gas Reporting in Germany with a quantitative assessment of organic carbon (C) stocks and changes in forest soils. Carbon stocks of the organic layer and the mineral topsoil (30 cm) were estimated on the basis of ca. 1.800 plots sampled from 1987 to 1992 and resampled from 2006 to 2008 on a nationwide grid of 8 × 8 km. Organic layer C stock estimates were attributed to surveyed forest stands and CORINE land cover data. Mineral soil C stock estimates were linked with the distribution of dominant soil types according to the Soil Map of Germany (1 : 1 000 000) and subsequently related to the forest area. It appears that the C pool of the organic layer was largely depending on tree species and parent material, whereas the C pool of the mineral soil varied among soil groups. We identified the organic layer C pool as stable although C was significantly sequestered under coniferous forest at lowland sites. The mineral soils, however, sequestered 0.41 Mg C ha(-1) yr(-1) . Carbon pool changes were supposed to depend on stand age and forest transformation as well as an enhanced biomass input. Carbon stock changes were clearly attributed to parent material and soil groups as sandy soils sequestered higher amounts of C, whereas clayey and calcareous soils showed small gains and in some cases even losses of soil C. We further showed that the largest part of the overall sample variance was not explained by fine-earth stock variances, rather by the C concentrations variance. The applied uncertainty analyses in this study link the variability of strata with measurement errors. In accordance to other studies for Central Europe, the results showed that the applied method enabled a reliable nationwide quantification of the soil C pool development for a certain period. PMID:24616061

  13. Conservation tillage versus conventional tillage on carbon stock in a Mediterranean dehesa (southern Spain)

    Science.gov (United States)

    Parras-Alcántara, Luis; Lozano-García, Beatriz

    2014-05-01

    determined were: soil particle size, bulk density, SOC, TN, C:N ratio, stocks and SR. The statistical significance of the differences in the variables between management practices was tested using the Anderson-Darling test at each horizon or a combination of horizons for each soil type. RESULTS The SOC-S was greater in CM (75.64 Mg ha-1) than in LP (44.01 Mg ha-1). SOC-S was very similar in OF and CT (CM [74.90 Mg ha-1-CT; 76.39 Mg ha-1-OF] and LP [44.77 Mg ha-1-CT; 43.25 Mg ha-1-OF]). Data analysis showed that management practices had little effect on SOC storage. Significant differences between soil types and management practices were found in SOC content for different horizons. The SR index was >2 in both soils types (CM and LP) and management systems (OF and CT). These results indicate that the soil is of high quality and that management practices have little influence on SOC-S (Parras-Alcántara et al., 2014) and do not affect SOC storage. REFERENCES Parras-Alcántara, L., Díaz-Jaimes, L., Lozano-García, B., Fernández Rebollo, P., Moreno Elcure, F., Carbonero Muñoz, M.D. 2014. Organic farming has little effect on carbon stock in a Mediterranean dehesa (southern Spain). Catena, 113: 9-17.

  14. INFLUENCE OF INVESTORS’ ATTENTION ON STOCK RETURN, LIQUIDITY, AND RETURN VOLATILITY COMPARISON BETWEEN MANUFACTURE COMPANIES IN INDONESIA AND INDIA

    OpenAIRE

    Puspita Sari, Noviana Icha

    2014-01-01

    This research aims to examine the influence of investors’ attention of company stock on stock return, liquidity, and return volatility comparison between manufacture companies in Indonesia and India in the year of 2011-2013. Investors’ attention is measured by a direct proxy which is Google Search Volume Index from Google trends. This research uses secondary data and processed by regression analysis. The samples are gathered from Indonesia stock exchange and India stock exchange. The result o...

  15. Developing Cost-Effective Field Assessments of Carbon Stocks in Human-Modified Tropical Forests.

    Directory of Open Access Journals (Sweden)

    Erika Berenguer

    Full Text Available Across the tropics, there is a growing financial investment in activities that aim to reduce emissions from deforestation and forest degradation, such as REDD+. However, most tropical countries lack on-the-ground capacity to conduct reliable and replicable assessments of forest carbon stocks, undermining their ability to secure long-term carbon finance for forest conservation programs. Clear guidance on how to reduce the monetary and time costs of field assessments of forest carbon can help tropical countries to overcome this capacity gap. Here we provide such guidance for cost-effective one-off field assessments of forest carbon stocks. We sampled a total of eight components from four different carbon pools (i.e. aboveground, dead wood, litter and soil in 224 study plots distributed across two regions of eastern Amazon. For each component we estimated survey costs, contribution to total forest carbon stocks and sensitivity to disturbance. Sampling costs varied thirty-one-fold between the most expensive component, soil, and the least, leaf litter. Large live stems (≥10 cm DBH, which represented only 15% of the overall sampling costs, was by far the most important component to be assessed, as it stores the largest amount of carbon and is highly sensitive to disturbance. If large stems are not taxonomically identified, costs can be reduced by a further 51%, while incurring an error in aboveground carbon estimates of only 5% in primary forests, but 31% in secondary forests. For rapid assessments, necessary to help prioritize locations for carbon- conservation activities, sampling of stems ≥20cm DBH without taxonomic identification can predict with confidence (R2 = 0.85 whether an area is relatively carbon-rich or carbon-poor-an approach that is 74% cheaper than sampling and identifying all the stems ≥10cm DBH. We use these results to evaluate the reliability of forest carbon stock estimates provided by the IPCC and FAO when applied to human

  16. Developing Cost-Effective Field Assessments of Carbon Stocks in Human-Modified Tropical Forests.

    Science.gov (United States)

    Berenguer, Erika; Gardner, Toby A; Ferreira, Joice; Aragão, Luiz E O C; Camargo, Plínio B; Cerri, Carlos E; Durigan, Mariana; Oliveira Junior, Raimundo C; Vieira, Ima C G; Barlow, Jos

    2015-01-01

    Across the tropics, there is a growing financial investment in activities that aim to reduce emissions from deforestation and forest degradation, such as REDD+. However, most tropical countries lack on-the-ground capacity to conduct reliable and replicable assessments of forest carbon stocks, undermining their ability to secure long-term carbon finance for forest conservation programs. Clear guidance on how to reduce the monetary and time costs of field assessments of forest carbon can help tropical countries to overcome this capacity gap. Here we provide such guidance for cost-effective one-off field assessments of forest carbon stocks. We sampled a total of eight components from four different carbon pools (i.e. aboveground, dead wood, litter and soil) in 224 study plots distributed across two regions of eastern Amazon. For each component we estimated survey costs, contribution to total forest carbon stocks and sensitivity to disturbance. Sampling costs varied thirty-one-fold between the most expensive component, soil, and the least, leaf litter. Large live stems (≥10 cm DBH), which represented only 15% of the overall sampling costs, was by far the most important component to be assessed, as it stores the largest amount of carbon and is highly sensitive to disturbance. If large stems are not taxonomically identified, costs can be reduced by a further 51%, while incurring an error in aboveground carbon estimates of only 5% in primary forests, but 31% in secondary forests. For rapid assessments, necessary to help prioritize locations for carbon- conservation activities, sampling of stems ≥20cm DBH without taxonomic identification can predict with confidence (R2 = 0.85) whether an area is relatively carbon-rich or carbon-poor-an approach that is 74% cheaper than sampling and identifying all the stems ≥10cm DBH. We use these results to evaluate the reliability of forest carbon stock estimates provided by the IPCC and FAO when applied to human-modified forests

  17. Developing Cost-Effective Field Assessments of Carbon Stocks in Human-Modified Tropical Forests

    Science.gov (United States)

    Berenguer, Erika; Gardner, Toby A.; Ferreira, Joice; Aragão, Luiz E. O. C.; Camargo, Plínio B.; Cerri, Carlos E.; Durigan, Mariana; Oliveira Junior, Raimundo C.; Vieira, Ima C. G.; Barlow, Jos

    2015-01-01

    Across the tropics, there is a growing financial investment in activities that aim to reduce emissions from deforestation and forest degradation, such as REDD+. However, most tropical countries lack on-the-ground capacity to conduct reliable and replicable assessments of forest carbon stocks, undermining their ability to secure long-term carbon finance for forest conservation programs. Clear guidance on how to reduce the monetary and time costs of field assessments of forest carbon can help tropical countries to overcome this capacity gap. Here we provide such guidance for cost-effective one-off field assessments of forest carbon stocks. We sampled a total of eight components from four different carbon pools (i.e. aboveground, dead wood, litter and soil) in 224 study plots distributed across two regions of eastern Amazon. For each component we estimated survey costs, contribution to total forest carbon stocks and sensitivity to disturbance. Sampling costs varied thirty-one-fold between the most expensive component, soil, and the least, leaf litter. Large live stems (≥10 cm DBH), which represented only 15% of the overall sampling costs, was by far the most important component to be assessed, as it stores the largest amount of carbon and is highly sensitive to disturbance. If large stems are not taxonomically identified, costs can be reduced by a further 51%, while incurring an error in aboveground carbon estimates of only 5% in primary forests, but 31% in secondary forests. For rapid assessments, necessary to help prioritize locations for carbon- conservation activities, sampling of stems ≥20cm DBH without taxonomic identification can predict with confidence (R2 = 0.85) whether an area is relatively carbon-rich or carbon-poor—an approach that is 74% cheaper than sampling and identifying all the stems ≥10cm DBH. We use these results to evaluate the reliability of forest carbon stock estimates provided by the IPCC and FAO when applied to human-modified forests

  18. Spatial variation in soil carbon stocks under a miscanthus crop

    OpenAIRE

    Hayes, Ciara

    2010-01-01

    Soils play an important role in the sequestration of soil carbon. Land management uses such as afforestation, grassland management etc can play a vital role in the mitigation of carbon from the atmosphere. Bioenergy crops are not only considered carbon neutral but may enhance the amount of C sequestered in the soils over time. In Ireland, field trials conducted using Miscanthus grass have estimated the soil organic carbon sequestration rate to be 0.6 t C ha-1.This study aims to investigate th...

  19. Increasing carbon sinks in European forests: effect of afforestation and changes in mean growing stock volume

    NARCIS (Netherlands)

    Vilén, T.; Cienciala, E.; Schelhaas, M.; Verkerk, P.J.; Lindner, M.; Peltola, H.

    2015-01-01

    In Europe, both forest area and growing stock have increased since the 1950s, and European forests have acted as a carbon sink during the last six decades. However, the contribution of different factors affecting the sink is not yet clear. In this study, historical inventory data were combined with

  20. Estimation of Biomass and Carbon Stocks in Rubber Plantation Using Thaichote Satellite Imagery

    Science.gov (United States)

    Charoenjit, Kitsanai; Zuddas, Pierpaolo; Allemand, Pascal

    2014-05-01

    This goal of study is to improve model for estimate biomass and carbon stocks of rubber plantation (clone RRIM 600) in sub-basin of mae num prasae, East Thailand with total area is 232 Km2. We mapped 2011 of the biomass and carbon stocks with the used of integrated Thaichote satellite imagery and field data. In order to tree girth prediction and tree density population, we applied the objected based image analysis (OBIA) which include image mining and modeling by linear multiple regression, then estimate biomass and carbon stocks in rubber plantation. The image mining includes spectral, vegetation, textural and mask information for modeling construction. We found an parameters of the Global Environmental Monitoring Index (GEMI) and texture of homogeneity, dissimilarity, contrast and variance were accepted relationship of tree girt prediction with R2 0.865. The total amount of biomass and carbon stocks in study area is 2,227 Kt and 991.5 KtC respectively. For summary of study area, the annual sequestered in 2011 is 121.3 tCO2 from the atmosphere and the rubber plantation at mature age stage (25 years) had highest capacity of sequestered at 33.53 tCO2 ha-1 yr-1.

  1. Aboveground carbon stocks in oil palm plantations and the threshold for carbon-neutral vegetation conversion on mineral soils

    NARCIS (Netherlands)

    Khasanah, N.; Noordwijk, van M.; Ningsih, H.

    2015-01-01

    The carbon (C) footprint of palm oil production is needed to judge emissions from potential biofuel use. Relevance includes wider sustainable palm oil debates. Within life cycle analysis, aboveground C debt is incurred if the vegetation replaced had a higher C stock than oil palm plantations. Our st

  2. Critical carbon input to maintain current soil organic carbon stocks in global wheat systems

    Science.gov (United States)

    Wang, Guocheng; Luo, Zhongkui; Han, Pengfei; Chen, Huansheng; Xu, Jingjing

    2016-01-01

    Soil organic carbon (SOC) dynamics in croplands is a crucial component of global carbon (C) cycle. Depending on local environmental conditions and management practices, typical C input is generally required to reduce or reverse C loss in agricultural soils. No studies have quantified the critical C input for maintaining SOC at global scale with high resolution. Such information will provide a baseline map for assessing soil C dynamics under potential changes in management practices and climate, and thus enable development of management strategies to reduce C footprint from farm to regional scales. We used the soil C model RothC to simulate the critical C input rates needed to maintain existing soil C level at 0.1° × 0.1° resolution in global wheat systems. On average, the critical C input was estimated to be 2.0 Mg C ha-1 yr-1, with large spatial variability depending on local soil and climatic conditions. Higher C inputs are required in wheat system of central United States and western Europe, mainly due to the higher current soil C stocks present in these regions. The critical C input could be effectively estimated using a summary model driven by current SOC level, mean annual temperature, precipitation, and soil clay content.

  3. Influence of information systems on stock management in little and middle sized supermarkets

    Directory of Open Access Journals (Sweden)

    Valdir Luis Pick

    2011-05-01

    Full Text Available This paper aims at presenting a multiple case study in which was analyzed the influence of information systems usage on the stock management processes in medium and little-sized retailers. We assessed four supermarkets from the inner land of Rio Grande do Sul, with different status in information systems development. The performance in stock management was appraised with the aid of five numerical indicators, defined in focus group sections with experts, led by researcher. The main observed influences were: average inventory, stock cycle, percentage of shortages and GM-ROI. WE observed high negative correlations between these variables and the level of usage of information systems: the more the company uses it, the less the variables grew, what is a desirable behavior. We do not found influence of the information system on sales volumes.

  4. The carbon copy of human activities : how long-term land use explains spatial variability of soil organic carbon stocks at multiple scales

    NARCIS (Netherlands)

    Schulp, C.J.E.

    2009-01-01

    Invloed van landgebruik, landgebruik-geschiedenis en management op de koolstofvoorraad in de bodem in Nederland.The carbon copy of human activities - how long-term land use explains spatial variability of soil organic carbon stocks at multiple scales.

  5. Modelling the effect of agricultural management practices on soil organic carbon stocks: does soil erosion matter?

    Science.gov (United States)

    Nadeu, Elisabet; Van Wesemael, Bas; Van Oost, Kristof

    2014-05-01

    Over the last decades, an increasing number of studies have been conducted to assess the effect of soil management practices on soil organic carbon (SOC) stocks. At regional scales, biogeochemical models such as CENTURY or Roth-C have been commonly applied. These models simulate SOC dynamics at the profile level (point basis) over long temporal scales but do not consider the continuous lateral transfer of sediment that takes place along geomorphic toposequences. As a consequence, the impact of soil redistribution on carbon fluxes is very seldom taken into account when evaluating changes in SOC stocks due to agricultural management practices on the short and long-term. To address this gap, we assessed the role of soil erosion by water and tillage on SOC stocks under different agricultural management practices in the Walloon region of Belgium. The SPEROS-C model was run for a 100-year period combining three typical crop rotations (using winter wheat, winter barley, sugar beet and maize) with three tillage scenarios (conventional tillage, reduced tillage and reduced tillage in combination with additional crop residues). The results showed that including soil erosion by water in the simulations led to a general decrease in SOC stocks relative to a baseline scenario (where no erosion took place). The SOC lost from these arable soils was mainly exported to adjacent sites and to the river system by lateral fluxes, with magnitudes differing between crop rotations and in all cases lower under conservation tillage practices than under conventional tillage. Although tillage erosion plays an important role in carbon redistribution within fields, lateral fluxes induced by water erosion led to a higher spatial and in-depth heterogeneity of SOC stocks with potential effects on the soil water holding capacity and crop yields. This indicates that studies assessing the effect of agricultural management practices on SOC stocks and other soil properties over the landscape should

  6. Geospatial assessment of long-term changes in carbon stocks and fluxes in forests of India (1930-2013)

    Science.gov (United States)

    Reddy, C. Sudhakar; Rakesh, F.; Jha, C. S.; Athira, K.; Singh, Sonali; Alekhya, V. V. L. Padma; Rajashekar, G.; Diwakar, P. G.; Dadhwal, V. K.

    2016-08-01

    The present study has estimated spatial distribution of biomass carbon density from satellite remote sensing data, historical archives and collateral data from 1930 to 2013. The spatial forest canopy density datasets for 1930, 1975, 1985, 1995, 2005 and 2013 were analysed to obtain biomass carbon pools at 5 km grid level. The overall loss of forest cover was 28% from 1930 to 2013. Analysis of change in the forest canopy density indicates that the dense forest cover reduced from 419,175 km2 in 1975 to 390,966 km2 in 2013. The total above ground biomass carbon stock of Indian forest was calculated as 3070.27 Tg C in 2013. Standing biomass carbon stocks varied significantly during different steps of time periods. There are a total 67,184 grid cells with loss of carbon stocks during 1930-1975 followed by 55,742 cells during 1975-1985. The annual carbon loss in the above ground biomass showed the highest decrease during the period of 1930 to 1975 and estimated as 2168.50 Tg C while the net annual loss of carbon is 48.19 Tg C. The maximum observed net annual loss of carbon stocks was 53.97 Tg C during 2005 to 2013. Carbon content for various states shows that maximum carbon stocks were stored in the forests of Arunachal Pradesh (11.27%) in 2013. State-wise change analysis indicates the highest loss of carbon stocks in Tripura (80.99%) from 1930 to 2013. Overall reduction in carbon stock in Indian forests has been estimated as 3079.98 Tg C (50.08%) from 1930 to 2013. The spatial characterization of distribution and changes in carbon stocks can provide useful information for planning and strategic management of resources and fulfilling global initiatives to conserve forest biodiversity.

  7. Impact of vegetation types on soil organic carbon stocks SOC-S in Mediterranean natural areas

    Science.gov (United States)

    Parras-Alcántara, Luis; Lozano-García, Beatriz; Cantudo-Pérez, Marta

    2015-04-01

    Soils play a key role in the carbon geochemical cycle because they can either emit large quantities of CO2 or on the contrary they can act as a store for carbon. Agriculture and forestry are the only activities that can achieve this effect through photosynthesis and the carbon incorporation into carbohydrates (Parras-Alcántara et al., 2013). The Mediterranean evergreen oak Woodland (MEOW - dehesa) is a type of pasture with scattered evergreen and deciduous oak stands in which cereals are often grown under the tree cover. It is a system dedicated to the combined production of Iberian swine, sheep, fuel wood, coal and cork as well as to hunting. These semi-natural areas still preserve some of the primitive vegetation of the Mediterranean oak forests. The dehesa is a pasture where the herbaceous layer is comprised of either cultivated cereals such as oat, barley and wheat or native vegetation dominated by annual species, which are used as grazing resources. These Iberian open woodland rangelands (dehesas) have been studied from different points of view: hydrologically, with respect to soil organic matter content, as well as in relation to gully erosion, topographical thresholds, soil erosion and runoff production, soil degradation and management practices…etc, among others. The soil organic carbon stock capacity depends not only on abiotic factors such as the mineralogical composition and the climate, but also on soil use and management (Parras et al., 2014 and 2015). In Spanish soils, climate, use and management strongly affect the carbon variability, mainly in soils in dry Mediterranean climates characterized by low organic carbon content, weak structure and readily degradable soils. Hontoria et al. (2004) emphasized that the climate and soil use are two factors that greatly influence carbon content in the Mediterranean climate. This research sought to analyze the SOC stock (SOCS) variability in MEOW - dehesa with cereals, olive grove and Mediterranean oak forest

  8. Analysis of Factors influence Non Performing Loan (NPL) at Go Public Bank at Indonesia Stock Exchange

    OpenAIRE

    Sitorus, Vera Yohana

    2015-01-01

    This research entitled “Analysis of Factors influence Non Performing Loan (NPL) at Go Public Bank at Indonesia Stock Exchange”. This research aims to respond any questions about factors influence the Non Performing Loan at the go public bank at Indonesia Stock Exchange. The bad loan is always found in banking loan activity. Therefore the bank always minimizes the bad loan to fulfill the requirement of Central Bank as the bank supervisors. The bad loan is total debt loan plus the doubt loan an...

  9. High-resolution mapping of forest carbon stocks in the Colombian Amazon

    Directory of Open Access Journals (Sweden)

    G. P. Asner

    2012-07-01

    Full Text Available High-resolution mapping of tropical forest carbon stocks can assist forest management and improve implementation of large-scale carbon retention and enhancement programs. Previous high-resolution approaches have relied on field plot and/or light detection and ranging (LiDAR samples of aboveground carbon density, which are typically upscaled to larger geographic areas using stratification maps. Such efforts often rely on detailed vegetation maps to stratify the region for sampling, but existing tropical forest maps are often too coarse and field plots too sparse for high-resolution carbon assessments. We developed a top-down approach for high-resolution carbon mapping in a 16.5 million ha region (> 40% of the Colombian Amazon – a remote landscape seldom documented. We report on three advances for large-scale carbon mapping: (i employing a universal approach to airborne LiDAR-calibration with limited field data; (ii quantifying environmental controls over carbon densities; and (iii developing stratification- and regression-based approaches for scaling up to regions outside of LiDAR coverage. We found that carbon stocks are predicted by a combination of satellite-derived elevation, fractional canopy cover and terrain ruggedness, allowing upscaling of the LiDAR samples to the full 16.5 million ha region. LiDAR-derived carbon maps have 14% uncertainty at 1 ha resolution, and the regional map based on stratification has 28% uncertainty in any given hectare. High-resolution approaches with quantifiable pixel-scale uncertainties will provide the most confidence for monitoring changes in tropical forest carbon stocks. Improved confidence will allow resource managers and decision makers to more rapidly and effectively implement actions that better conserve and utilize forests in tropical regions.

  10. High-resolution Mapping of Forest Carbon Stocks in the Colombian Amazon

    Directory of Open Access Journals (Sweden)

    G. P. Asner

    2012-03-01

    Full Text Available High-resolution mapping of tropical forest carbon stocks can assist forest management and improve implementation of large-scale carbon retention and enhancement programs. Previous high-resolution approaches have relied on field plot and/or Light Detection and Ranging (LiDAR samples of aboveground carbon density, which are typically upscaled to larger geographic areas using stratification maps. Such efforts often rely on detailed vegetation maps to stratify the region for sampling, but existing tropical forest maps are often too coarse and field plots too sparse for high resolution carbon assessments. We developed a top-down approach for high-resolution carbon mapping in a 16.5 million ha region (>40 % of the Colombian Amazon – a remote landscape seldom documented. We report on three advances for large-scale carbon mapping: (i employing a universal approach to airborne LiDAR-calibration with limited field data; (ii quantifying environmental controls over carbon densities; and (iii developing stratification- and regression-based approaches for scaling up to regions outside of LiDAR coverage. We found that carbon stocks are predicted by a combination of satellite-derived elevation, fractional canopy cover and terrain ruggedness, allowing upscaling of the LiDAR samples to the full 16.5 million ha region. LiDAR-derived carbon mapping samples had 14.6 % uncertainty at 1 ha resolution, and regional maps based on stratification and regression approaches had 25.6 % and 29.6 % uncertainty, respectively, in any given hectare. High-resolution approaches with reported local-scale uncertainties will provide the most confidence for monitoring changes in tropical forest carbon stocks. Improved confidence will allow resource managers and decision-makers to more rapidly and effectively implement actions that better conserve and utilize forests in tropical regions.

  11. US Forest Service Forest Carbon Stocks Contiguous United States

    Data.gov (United States)

    US Forest Service, Department of Agriculture — Through application of a nearest-neighbor imputation approach, mapped estimates of forest carbon density were developed for the contiguous United States using the...

  12. Forest conversion to poplar plantation in a Lombardy floodplain (Italy: effects on soil organic carbon stock

    Directory of Open Access Journals (Sweden)

    C. Ferré

    2014-06-01

    Full Text Available Effects of forest conversion to poplar plantation on soil organic carbon (SOC stocks were investigated by sampling paired plots in an alluvial area of the Ticino river in Northern Italy. According to land registers and historical aerial photographs, the two sites were part of a larger area of a 200 years-old natural forest that was partly converted to poplar plantation in 1973. The soil sampling of three layers down to a depth of 100 cm was performed at 90 and 70 points in the natural forest (NF and in the nearby poplar plantation (PP, respectively. The substitution of the natural forest with the poplar plantation strongly modified soil C stock down to a depth of 55 cm, although the management practices at PP were not intensive. By evaluation of equivalent soil masses, the comparison of C stocks (organic layer included between the different land uses showed a decrease in SOC of 5.7 kg m−2 after 37 years of poplar cultivation, corresponding to more than 1/3 of the initial organic carbon content. The land use change from NF to PP not only affected the stock but also the vertical distribution of SOC: ploughing led to the transfer of SOC from soil surface into the deeper layers resulting in a more uniform allocation of organic carbon in the ploughed layer and disappearance of the SOC stratification observed in the forest.

  13. Mapping organic carbon stocks in eucalyptus plantations of the central highlands of Madagascar : a multiple regression approach

    OpenAIRE

    Razakamanarivo, R. H.; Grinand, Clovis; Razafindrakoto, M. A.; Bernoux, Martial; Albrecht, Alain

    2011-01-01

    Recent concerns about global warming have resulted in more concerted studies on quantification and modeling of carbon (C) storage in different ecosystems. The aim of this study was to assess and map the carbon stocks in above (ABG), below-ground (BLG) biomass and soil organic carbon contained in the 30 centimeter top-layer (SOC) in coppices of eucalyptus plantations in the central highlands of Madagascar in an area of 1590 ha. Relationships between C stock and various biophysical (stool or sh...

  14. Land use change and management effects on soil organic carbon stock and soil quality in Mediterranean areas

    Science.gov (United States)

    Lozano-García, Beatriz; Parras-Alcántara, Luis

    2016-04-01

    INTRODUCTION Both land use and management affects to soil properties and soil quality. On the one hand, land use change from natural vegetation to agricultural land often is a key factor that influences to soil. On the other hand, under semiarid climatic conditions, intensive tillage increases soil organic matter losses, reduces soil quality, and contributes to climate change due to increased CO2 emissions. MATERIAL AND METHODS A field study was conducted to determine the land use change [Mediterranean evergreen oak woodland (MEOW-dehesa) to olive grove (OG) and cereal (C), all of them managed under conventional tillage and under conservationist practices] effects on soil organic carbon (SOC) stocks and the soil quality [through Stratification Ratios (SR)] in Los Pedroches valley, southern Spain. RESULTS Results for the present study indicate that in MEOW-dehesa management practices had little effect on SOC storage. The stratification ratio was >2 in both management systems, so, soils under MEOW-dehesa had high quality. Nevertheless, in OG and C conservationist practices increased SOC stocks. Therefore, conservationist practices contributed to a better soil quality and to increased carbon sequestration and, consequently, this management is an excellent alternative to conventional tillage. A change in land use from MEOW-dehesa to OG or C under conservationist practices appeared to increase the SOC. When calculated for the total soil profile these differences were equivalent to 20-25 Mg ha‑1 of SOC. This is potentially very important for many agricultural soils in the Mediterranean area which are typically very poor in organic matter. These differences in the SOC stock were not apparent when the change in land use occurred under conventional tillage; even in the land use change from MEOW-dehesa to C the SOC stock was reduced. This suggests that management in addition to change in land use is an important consideration and particularly the degree of soil disturbance

  15. Carbon stock and carbon turnover in boreal and temperate forests - Integration of remote sensing data and global vegetation models

    Science.gov (United States)

    Thurner, Martin; Beer, Christian; Carvalhais, Nuno; Forkel, Matthias; Tito Rademacher, Tim; Santoro, Maurizio; Tum, Markus; Schmullius, Christiane

    2016-04-01

    Long-term vegetation dynamics are one of the key uncertainties of the carbon cycle. There are large differences in simulated vegetation carbon stocks and fluxes including productivity, respiration and carbon turnover between global vegetation models. Especially the implementation of climate-related mortality processes, for instance drought, fire, frost or insect effects, is often lacking or insufficient in current models and their importance at global scale is highly uncertain. These shortcomings have been due to the lack of spatially extensive information on vegetation carbon stocks, which cannot be provided by inventory data alone. Instead, we recently have been able to estimate northern boreal and temperate forest carbon stocks based on radar remote sensing data. Our spatially explicit product (0.01° resolution) shows strong agreement to inventory-based estimates at a regional scale and allows for a spatial evaluation of carbon stocks and dynamics simulated by global vegetation models. By combining this state-of-the-art biomass product and NPP datasets originating from remote sensing, we are able to study the relation between carbon turnover rate and a set of climate indices in northern boreal and temperate forests along spatial gradients. We observe an increasing turnover rate with colder winter temperatures and longer winters in boreal forests, suggesting frost damage and the trade-off between frost adaptation and growth being important mortality processes in this ecosystem. In contrast, turnover rate increases with climatic conditions favouring drought and insect outbreaks in temperate forests. Investigated global vegetation models from the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), including HYBRID4, JeDi, JULES, LPJml, ORCHIDEE, SDGVM, and VISIT, are able to reproduce observation-based spatial climate - turnover rate relationships only to a limited extent. While most of the models compare relatively well in terms of NPP, simulated

  16. Spatial Variability of Soil Carbon Stocks in a Subtropical Mangrove in Hong Kong

    Science.gov (United States)

    Lai, D. Y. F.; Neogi, S.; Law, M. S. M.; Xu, J.; Glatzel, S.; Buczko, U.; Karstens, S.

    2015-12-01

    "Blue carbon", a term used for carbon (C) sequestered in vegetated coastal wetlands, has received increasing attention recently as a potential option for mitigating future climate change. While coastal mangrove is considered as one of the most carbon-rich ecosystems of the world, there is a need to better characterize and compare the magnitude of carbon storage among mangroves in different geographical regions. In this study, we quantified the spatial variability of soil carbon stocks in a subtropical mangrove wetland in Hong Kong, and examined the effects of land cover change on soil carbon storage. Bare mudflats contained significantly lower amount of carbon than mangroves in the top 1 m soils (94.7 vs. 130.7-163.8 Mg C ha-1), indicating the importance of vegetation in enhancing C sequestration. Moreover, we observed higher soil C storage in sites dominated by Avicennia marina than those dominated by Kandelia obovata. Conversion of natural mangroves into freshwater marshes and brackish ponds with shallow islands significantly reduced the amount of C stored in the top 30 cm soils by 24-58%, when compared to sites dominated by mangrove trees. Our findings suggest that consideration should be given to plant species and land cover type in determining the overall magnitude of carbon stocks in subtropical mangrove soils.

  17. Evaluating the Potential of Commercial Forest Inventory Data to Report on Forest Carbon Stock and Forest Carbon Stock Changes for REDD+ under the UNFCCC

    OpenAIRE

    Danae Maniatis; Yadvinder Malhi; Laurent Saint André; Danilo Mollicone; Nicolas Barbier; Sassan Saatchi; Matieu Henry; Laurent Tellier; Mathieu Schwartzenberg; Lee White

    2011-01-01

    In the context of the adoption at the 16th Conference of the Parties in 2010 on the REDD+ mitigation mechanism, it is important to obtain reliable data on the spatiotemporal variation of forest carbon stocks and changes (called Emission Factor, EF). A re-occurring debate in estimating EF for REDD+ is the use of existing field measurement data. We provide an assessment of the use of commercial logging inventory data and ecological data to estimate a conservative EF (REDD+ phase 2) or to report...

  18. Convergent modeling of past soil organic carbon stocks but divergent projections

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    Z. Luo

    2015-03-01

    Full Text Available Soil carbon models are important tool to understand soil carbon balance and project carbon stocks in terrestrial ecosystems, particularly under global change. The initialization and/or parameterization of soil carbon models can vary among studies even when the same model and dataset are used, causing potential uncertainties in projections. Although a few studies have assessed such uncertainties, it is yet unclear what these uncertainties are correlated with and how they change across varying environmental and management conditions. Here, applying a process-based biogeochemical model to 90 individual field experiments (ranging from 5 to 82 years of experimental duration across the Australian cereal-growing regions, we demonstrated that well-designed calibration procedures enabled the model to accurately simulate changes in measured carbon stocks, but did not guarantee convergent forward projections (100 years. Major causes of the projection uncertainty were due to insufficient understanding of how microbial processes and soil carbon composition change to modulate carbon turnover. For a given site, the uncertainty significantly increased with the magnitude of future carbon input and years of the projection. Across sites, the uncertainty correlated positively with temperature, but negatively with rainfall. On average, a 331% uncertainty in projected carbon sequestration ability can be inferred in Australian agricultural soils. This uncertainty would increase further if projections were made for future warming and drying conditions. Future improvement in soil carbon modeling should focus on how microbial community and its carbon use efficiency change in response to environmental changes, better quantification of composition of soil carbon and its change, and how the soil carbon composition will affect its turnover time.

  19. An increased understanding of soil organic carbon stocks and changes in non-temperate areas : National and global implications

    OpenAIRE

    Milne, E; K. Paustian; Easter, M; Sessay, M.; Al Adamat, R.; Batjes, N.H.; Bernoux, Martial; Bhattacharyya, T; Cerri, C. C.,; Cerri, C. E. P.,; Coleman, K.; Falloon, P.; Feller, Christian; Gicheru, P.; Kamoni, P.

    2007-01-01

    National and sub-national scale estimates of soil organic carbon (SOC) stocks and changes can provide information land degradation risk, C sequestration possibilities and the potential sustainability of proposed land management plans. Under a GEF co-financed project, 'The GEFSOC Modelling System' was used to determine SOC stocks and projected stock change rates for four case study areas; The Brazilian Amazon, The Indo-Gangetic Plains of India, Kenya and Jordan. Each case study represented soi...

  20. Alaskan soil carbon stocks: spatial variability and dependence on environmental factors

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    U. Mishra

    2012-05-01

    Full Text Available The direction and magnitude of soil organic carbon (SOC changes in response to climate change depend on the spatial and vertical distributions of SOC. We estimated spatially-resolved SOC stocks from surface to C horizon, distinguishing active-layer and permafrost-layer stocks, based on geospatial analysis of 472 soil profiles and spatially referenced environmental variables for Alaska. Total Alaska state-wide SOC stock was estimated to be 77 Pg, with 61% in the active-layer, 27% in permafrost, and 12% in non-permafrost soils. Prediction accuracy was highest for the active-layer as demonstrated by highest ratio of performance to deviation (1.5. Large spatial variability was predicted, with whole-profile, active-layer, and permafrost-layer stocks ranging from 1–296 kg C m−2, 2–166 kg m−2, and 0–232 kg m−2, respectively. Temperature and soil wetness were found to be primary controllers of whole-profile, active-layer, and permafrost-layer SOC stocks. Secondary controllers, in order of importance, were: land cover type, topographic attributes, and bedrock geology. The observed importance of soil wetness rather than precipitation on SOC stocks implies that the poor representation of high-latitude soil wetness in Earth System Models may lead to large uncertainty in predicted SOC stocks under future climate change scenarios. Under strict caveats described in the text and assuming temperature changes from the A1B Intergovernmental Panel on Climate Change emissions scenario, our geospatial model indicates that the equilibrium average 2100 Alaska active-layer depth could deepen by 11 cm, resulting in a thawing of 13 Pg C currently in permafrost. The equilibrium SOC loss associated with this warming would be highest under continuous permafrost (31%, followed by discontinuous (28%, isolated (24.3%, and sporadic (23.6% permafrost areas. Our high resolution mapping of soil carbon stock reveals the potential

  1. Alaskan soil carbon stocks: spatial variability and dependence on environmental factors

    Directory of Open Access Journals (Sweden)

    U. Mishra

    2012-09-01

    Full Text Available The direction and magnitude of soil organic carbon (SOC changes in response to climate change depend on the spatial and vertical distributions of SOC. We estimated spatially resolved SOC stocks from surface to C horizon, distinguishing active-layer and permafrost-layer stocks, based on geospatial analysis of 472 soil profiles and spatially referenced environmental variables for Alaska. Total Alaska state-wide SOC stock was estimated to be 77 Pg, with 61% in the active-layer, 27% in permafrost, and 12% in non-permafrost soils. Prediction accuracy was highest for the active-layer as demonstrated by highest ratio of performance to deviation (1.5. Large spatial variability was predicted, with whole-profile, active-layer, and permafrost-layer stocks ranging from 1–296 kg C m−2, 2–166 kg m−2, and 0–232 kg m−2, respectively. Temperature and soil wetness were found to be primary controllers of whole-profile, active-layer, and permafrost-layer SOC stocks. Secondary controllers, in order of importance, were found to be land cover type, topographic attributes, and bedrock geology. The observed importance of soil wetness rather than precipitation on SOC stocks implies that the poor representation of high-latitude soil wetness in Earth system models may lead to large uncertainty in predicted SOC stocks under future climate change scenarios. Under strict caveats described in the text and assuming temperature changes from the A1B Intergovernmental Panel on Climate Change emissions scenario, our geospatial model indicates that the equilibrium average 2100 Alaska active-layer depth could deepen by 11 cm, resulting in a thawing of 13 Pg C currently in permafrost. The equilibrium SOC loss associated with this warming would be highest under continuous permafrost (31%, followed by discontinuous (28%, isolated (24.3%, and sporadic (23.6% permafrost areas. Our high-resolution mapping of soil carbon stock reveals the

  2. Modeling soil organic carbon stocks and changes in Spain using the GEFSOC system

    Science.gov (United States)

    Álvaro-Fuentes, Jorge; Easter, Mark; Cantero-Martínez, Carlos; Paustian, Keith

    2010-05-01

    Currently, there is little information about soil organic carbon (SOC) stocks in Spain. To date the effects of land-use and soil management on SOC stocks in Spain have been evaluated in experimental fields under certain soil and climate conditions. However, these field experiments do not account for the spatial variability in management, cropping systems and soil and climate characteristics that exist in the whole territory. More realistic approaches like ecosystem-level dynamic simulation systems linked to geographic information systems (GIS) allow better assessments of SOC stocks at a regional or national level. The Global Environmental Facility Soil Organic Carbon (GEFSOC) system was recently built for this purpose (Milne et al., 2007) and it incorporates three widely used models for estimating SOC dynamics: (a) the Century ecosystem model; (b) the RothC soil C decomposition model; and (c) the Intergovernmental Panel on Climate Change (IPCC) method for assessing soil C at regional scales. We modeled 9.5 Mha in northeast Spain using the GEFSOC system to predict SOC stocks and changes comprising: pasture, forest, cereal-fallow, cereal monoculture, orchards, rice, irrigated land and grapes and olives. The spatial distribution of the different land use categories and their change over time was obtained from the European Corine database and from Spanish census data on land use from 1926 to 2007. At the same time, current and historical management information was collected from different sources in order to have a fairly well picture of changes in land use and management for this area. Soil parameters needed by the system were obtained from the European soil map (1 km x 1 km) and climate data was produced by the Meteorology State Agency (Ministry of the Environment and Rural and Marine Environs of Spain). The SOC stocks simulated were validated with SOC values from the European SOC map and from other national studies. Modeled SOC results suggested that spatial

  3. Soil organic carbon pools and stocks in permafrost-affected soils on the tibetan plateau.

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    Corina Dörfer

    Full Text Available The Tibetan Plateau reacts particularly sensitively to possible effects of climate change. Approximately two thirds of the total area is affected by permafrost. To get a better understanding of the role of permafrost on soil organic carbon pools and stocks, investigations were carried out including both discontinuous (site Huashixia, HUA and continuous permafrost (site Wudaoliang, WUD. Three organic carbon fractions were isolated using density separation combined with ultrasonic dispersion: the light fractions (1.6 g cm(-3 of mineral associated organic matter (MOM. The fractions were analyzed for C, N, and their portion of organic C. FPOM contained an average SOC content of 252 g kg(-1. Higher SOC contents (320 g kg(-1 were found in OPOM while MOM had the lowest SOC contents (29 g kg(-1. Due to their lower density the easily decomposable fractions FPOM and OPOM contribute 27% (HUA and 22% (WUD to the total SOC stocks. In HUA mean SOC stocks (0-30 cm depth account for 10.4 kg m(-2, compared to 3.4 kg m(-2 in WUD. 53% of the SOC is stored in the upper 10 cm in WUD, in HUA only 39%. Highest POM values of 36% occurred in profiles with high soil moisture content. SOC stocks, soil moisture and active layer thickness correlated strongly in discontinuous permafrost while no correlation between SOC stocks and active layer thickness and only a weak relation between soil moisture and SOC stocks could be found in continuous permafrost. Consequently, permafrost-affected soils in discontinuous permafrost environments are susceptible to soil moisture changes due to alterations in quantity and seasonal distribution of precipitation, increasing temperature and therefore evaporation.

  4. Modelling soil carbon flows and stocks following a carbon balance approach at regional scale for the EU-27

    Science.gov (United States)

    Lesschen, Jan Peter; Sikirica, Natasa; Bonten, Luc; Dibari, Camilla; Sanchez, Berta; Kuikman, Peter

    2014-05-01

    Soil Organic Carbon (SOC) is a key parameter to many soil functions and services. SOC is essential to support water retention and nutrient buffering and mineralization in the soil as well as to enhance soil biodiversity. Consequently, loss of SOC or low SOC levels might threaten soil productivity or even lead to a collapse of a farming system. Identification of areas in Europe with critically low SOC levels or with a negative carbon balance is a challenge in order to apply the appropriate strategies to restore these areas or prevent further SOC losses. The objective of this study is to assess current soil carbon flows and stocks at a regional scale; we follow a carbon balance approach which we developed within the MITERRA-Europe model. MITERRA-Europe is an environmental impact assessment model and calculates nitrogen and greenhouse emission on a deterministic and annual basis using emission and leaching factors at regional level (NUTS2, comparable to province level) in the EU27. The model already contained a soil carbon module based on the IPCC stock change approach. Within the EU FP7 SmartSoil project we developed a SOC balance approach, for which we quantified the input of carbon (manure, crop residues, other organic inputs) and the losses of carbon (decomposition, leaching and erosion). The calculations rules from the Roth-C model were used to estimate SOC decomposition. For the actual soil carbon stocks we used the data from the LUCAS soil sample survey. LUCAS collected soil samples in 2009 at about 22000 locations across the EU, which were analysed for a range of soil properties. Land management practices are accounted for, based on data from the EU wide Survey on Agricultural Production Methods in the 2010 Farm Structure Survey. The survey comprises data on the application of soil tillage, soil cover, crop rotation and irrigation. Based on the simulated soil carbon balance and the actual carbon stocks from LUCAS we now can identify regions within the EU that

  5. Effects of Successive Rotation Regimes on Carbon Stocks in Eucalyptus Plantations in Subtropical China Measured over a Full Rotation.

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    Xiaoqiong Li

    Full Text Available Plantations play an important role in carbon sequestration and the global carbon cycle. However, there is a dilemma in that most plantations are managed on short rotations, and the carbon sequestration capacities of these short-rotation plantations remain understudied. Eucalyptus has been widely planted in the tropics and subtropics due to its rapid growth, high adaptability, and large economic return. Eucalyptus plantations are primarily planted in successive rotations with a short rotation length of 6~8 years. In order to estimate the carbon-stock potential of eucalyptus plantations over successive rotations, we chose a first rotation (FR and a second rotation (SR stand and monitored the carbon stock dynamics over a full rotation from 1998 to 2005. Our results showed that carbon stock in eucalyptus trees (TC did not significantly differ between rotations, while understory vegetation (UC and soil organic matter (SOC stored less carbon in the SR (1.01 vs. 2.76 Mg.ha(-1 and 70.68 vs. 81.08 Mg. ha(-1, respectively and forest floor carbon (FFC conversely stored more (2.80 vs. 2.34 Mg. ha(-1. The lower UC and SOC stocks in the SR stand resulted in 1.13 times lower overall ecosystem carbon stock. Mineral soils and overstory trees were the two dominant carbon pools in eucalyptus plantations, accounting for 73.77%~75.06% and 20.50%~22.39%, respectively, of the ecosystem carbon pool. However, the relative contribution (to the ecosystem pool of FFC stocks increased 1.38 times and that of UC decreased 2.30 times in the SR versus FR stand. These carbon pool changes over successive rotations were attributed to intensive successive rotation regimes of eucalyptus plantations. Our eight year study suggests that for the sustainable development of short-rotation plantations, a sound silvicultural strategy is required to achieve the best combination of high wood yield and carbon stock potential.

  6. INFLUENCE OF TRANSPORT FACTOR ON STOCKS IN LOGISTICS CHAINS OF RESOURCE BEHAVIOU

    Directory of Open Access Journals (Sweden)

    I. A. Lebedeva

    2014-11-01

    Full Text Available The paper considers behaviour of material flows at stages of complicated  logistic industrial and transport systems. Key parameters of logistic delivery schemes are analyzed in the paper. The paper estimates an influence of a time parameter on the level of transport and logistics costs and, as a consequence, on  a final finished product.While determining a stock level it is necessary to know not only an intensity of material resource consumption by manufacturing process  for a concrete period of time, but also a probability of non-observance of   transport service terms and cost of stock storage. Stocks of mass cargoes are basically formed at first stages of industrial and transport system and cost of their storage is relatively insignificant. However deficit presence of the given resources influences on functioning of all subsequent interrelated stages of the industrial and transport system.Thus, a risk of deficit occurrence of the given resources can be probably reduced by creating a high stock rate. There is a processing of hi-tech component items (or half-finished products at last stages of the industrial and transport system. Expenses on storage of such resources  are usually high and possibility of their substitution by analogous ones is insignificant. At last stages a mobilization of facilities for provision of on-time delivery is more profitable that allows to save on stock arrangement.

  7. Soil organic carbon stock changes in the contiguous United States from 1920s to 2010s

    Science.gov (United States)

    Cao, B.; Grunwald, S.; Ferguson, H. J.; Hempel, J. W.; Xiong, X.; Patarasuk, R.; Ross, C. W.

    2014-12-01

    To investigate the changes of soil organic carbon (SOC) stocks is of great importance to understand soil carbon dynamics and develop greenhouse gas mitigation and adaptation strategies. There are research gaps in understanding how natural environmental and anthropogenic factors (such as socio-cultural and political/legislative) have provided positive and negative feedbacks on SOC stocks since the 1920s at continental scale. The objectives of this study were to 1) determine the temporal trends in SOC storage across the contiguous U.S.; 2) explore the factors that can explain if soils have acted as a carbon source or sink during the period from 1920s to 2010. We used two soil datasets: 1) National Characterization Soil Survey Database (NCSS) from 1924 to 2010, which includes a total of 14,493 site observations with mutiple soil horizons within 0-100 cm; 2) The data from the Rapid Carbon Assessment (RaCA) Project, containing a total of 6,409 site observations to the maximum depth of 100 cm (2010-2012). We also extracted environmental covariates (space-time layers) covering the U.S. from various sources (remote sensing, National Elevation Dataset, climate data from PRISM project, etc.) to those sites. Results show a fluctuating trend of SOC stocks from 4 kg m-2 in 1920-1930 to 6 kg m-2 in 2010 in the 0-20 cm profile, and from 9 kg m-2 in 1920-1930 to 17 kg m-2 in 2010 in the 0-100 cm profile, respectively. However, there had been a decrease of SOC stock from 1975 to 1985 in both the 0-20 cm and 0-100 cm profiles. Our analysis reveals relationships between SOC storage and major pivotal political/legislative and socio-cultural events as well as environmental factors. The variation of SOC across the contiguous U.S. was affected in some periods by environmental legislation while in others natural effects predominated. The SOC stock change assessment can be used to infer on the magnitude and past trends; and thus, allows some insight how past natural and anthropogenic

  8. Comparison of the carbon stock in forest soil of sessile oak and beech forests

    Science.gov (United States)

    Horváth, Adrienn; Bene, Zsolt; Bidló, András

    2016-04-01

    Forest ecosystems are the most important carbon sinks. The forest soils play an important role in the global carbon cycle, because the global climate change or the increase of atmospheric CO2 level. We do not have enough data about the carbon stock of soils and its change due to human activities, which have similar value to carbon content of biomass. In our investigation we measured the carbon stock of soil in 10 stands of Quercus petraea and Fagus sylvatica. We took a 1.1 m soil column with soil borer and divided to 11 samples each column. The course organic and root residues were moved. After evaluation, we compared our results with other studies and the carbon stock of forests to each other. Naturally, the amount of SOC was the highest in the topsoil layers. However, we found significant difference between forest stands which stayed on the same homogenous bedrock, but very close to each other (e.g. distance was 1 or 2 km). We detected that different forest utilizations and tree species have an effect on the forest carbon as the litter as well (amount, composition). In summary, we found larger amount (99.1 C t/ha on average) of SOC in soil of stands, where sessile oak were the main stand-forming tree species. The amount of carbon was the least in turkey oak-sessile oak stands (85.4 C t/ha on average). We found the highest SOC (118.3 C t/ha) in the most mixed stand (silver lime-beech-red oak). In the future, it will be very important: How does climate change affect the spread of tree species or on carbon storage? Beech is more sensitive, but even sessile oak. These species are expected to replace with turkey oak, which is less sensitive to drought. Thus, it is possible in the future that we can expect to decrease of forest soil carbon stock capacity, which was confirmed by our experiment. Keywords: carbon sequestration, mitigation, Fagus sylvatica, Quercus petraea, litter Acknowledgements: Research is supported by the "Agroclimate.2" (VKSZ_12-1-2013-0034) EU

  9. The soil classification and the subsurface carbon stock estimation with a ground-penetrating radar

    International Nuclear Information System (INIS)

    One of the serious problems of the Kyoto Protocol is that we have no effective method to estimate the carbon stock of the subsurface. To solve this problem, we propose the application of ground-penetrating radar (GPR) to the subsurface soil survey. As a result, it is shown that GPR can detect the soil horizons, stones and roots. The fluctuations of the soil horizons in the forest are cleanly indicated as the reflection pattern of the microwaves. Considering the fact that the physical, chemical, and biological characteristics of each soil layer is almost unique, GPR results can be used to estimate the carbon stock in soil by combining with the vertical soil sample survey at one site. Then as a trial, we demonstrate to estimate the carbon content fixed in soil layers based on the soil samples and GPR survey data. we also compare this result with the carbon stock for the flat horizon case. The advantages of GPR usage for this object are not only the reduction of uncertainty and the cost, but also the environmental friendliness of survey manner. Finally, we summarize the adaptabilities of various antennas having different predominant frequencies for the shallow subsurface zone. (author)

  10. Aboveground biomass and carbon stocks modelling using non-linear regression model

    Science.gov (United States)

    Ain Mohd Zaki, Nurul; Abd Latif, Zulkiflee; Nazip Suratman, Mohd; Zainee Zainal, Mohd

    2016-06-01

    Aboveground biomass (AGB) is an important source of uncertainty in the carbon estimation for the tropical forest due to the variation biodiversity of species and the complex structure of tropical rain forest. Nevertheless, the tropical rainforest holds the most extensive forest in the world with the vast diversity of tree with layered canopies. With the usage of optical sensor integrate with empirical models is a common way to assess the AGB. Using the regression, the linkage between remote sensing and a biophysical parameter of the forest may be made. Therefore, this paper exemplifies the accuracy of non-linear regression equation of quadratic function to estimate the AGB and carbon stocks for the tropical lowland Dipterocarp forest of Ayer Hitam forest reserve, Selangor. The main aim of this investigation is to obtain the relationship between biophysical parameter field plots with the remotely-sensed data using nonlinear regression model. The result showed that there is a good relationship between crown projection area (CPA) and carbon stocks (CS) with Pearson Correlation (p order to quantify the AGB and carbon stocks for a larger sample area of the lowland Dipterocarp forest.

  11. Biomass Stock and Carbon Sequestration in a Chronosequence of Pinus massoniana Plantations in the Upper Reaches of the Yangtze River

    Directory of Open Access Journals (Sweden)

    Meta Francis Justine

    2015-10-01

    Full Text Available Planted forest plays a significant role in carbon sequestration and climate change mitigation; however, little information has been available on the distribution patterns of carbon pools with stand ages in Pinus massoniana Plantations. We investigated the biomass stock and carbon sequestration across a chronosequence (3-, 5-, 7-, 9-, 12-, 15-, 19-, 29-, 35- and 42-year of stands with the main objectives: (1 to determine the biomass and carbon stock of the forest ecosystem; and (2 to identify factors influencing their distribution across the age series. Simple random sampling was used for collecting field data in the ten (10 stand ages. Three 20 × 20 m standard plots were laid out in February 2015 across the chronosequence. The diameter at breast height (DBH and tree height (H of each tree within each plot were measured using calipers and height indicator. Sub-plots of 2 × 2 m were established in each main plot for collecting soil samples at a 0–30- and 30–60-cm depth. Plantation biomass increased with increasing stand ages, ranging from 0.84 tonnes per hectare (t·ha−1 in the three-year stand to 252.35 t·ha−1 in the 42-year stand. The aboveground biomass (AGB contributed 86.51%; the maximum value is 300-times the minimum value. Carbon concentrations and storage in mineral soil decreased with increasing soil depth, but were controlled by the management history of the ecosystem. The total ecosystem carbon storage varies with stand ages, ranging from 169.90 t·ha−1 in the five-year plantation to 326.46 t·ha−1 in the 42-year plantation, of which 80.29% comes from the mineral soil carbon and 19.71% from the vegetation. The ratio of the total carbon sequestration by the 42-year to the three-year stand was 1.70, implying substantial amounts of carbon accumulation during the transition period from young to mature-aged trees. The forest ecosystem had the capacity of storing up to 263.16 t·ha−1 carbon, assisting in mitigating climate

  12. Soil and vegetation carbon stocks in Brazilian Western Amazonia: relationships and ecological implications for natural landscapes.

    Science.gov (United States)

    Schaefer, C E G R; do Amaral, E F; de Mendonça, B A F; Oliveira, H; Lani, J L; Costa, L M; Fernandes Filho, E I

    2008-05-01

    The relationships between soils attributes, soil carbon stocks and vegetation carbon stocks are poorly know in Amazonia, even at regional scale. In this paper, we used the large and reliable soil database from Western Amazonia obtained from the RADAMBRASIL project and recent estimates of vegetation biomass to investigate some environmental relationships, quantifying C stocks of intact ecosystem in Western Amazonia. The results allowed separating the western Amazonia into 6 sectors, called pedo-zones: Roraima, Rio Negro Basin, Tertiary Plateaux of the Amazon, Javari-Juruá-Purus lowland, Acre Basin and Rondonia uplands. The highest C stock for the whole soil is observed in the Acre and in the Rio Negro sectors. In the former, this is due to the high nutrient status and high clay activity, whereas in the latter, it is attributed to a downward carbon movement attributed to widespread podzolization and arenization, forming spodic horizons. The youthful nature of shallow soils of the Javari-Juruá-Purus lowlands, associated with high Al, results in a high phytomass C/soil C ratio. A similar trend was observed for the shallow soils from the Roraima and Rondonia highlands. A consistent east-west decline in biomass carbon in the Rio Negro Basin sector is associated with increasing rainfall and higher sand amounts. It is related to lesser C protection and greater C loss of sandy soils, subjected to active chemical leaching and widespread podzolization. Also, these soils possess lower cation exchangeable capacity and lower water retention capacity. Zones where deeply weathered Latosols dominate have a overall pattern of high C sequestration, and greater than the shallower soils from the upper Amazon, west of Madeira and Negro rivers. This was attributed to deeper incorporation of carbon in these clayey and highly pedo-bioturbated soils. The results highlight the urgent need for refining soil data at an appropriate scale for C stocks calculations purposes in Amazonia. There

  13. How can soil organic carbon stocks in agriculture be maintained or increased?

    Science.gov (United States)

    Don, Axel; Leifeld, Jens

    2015-04-01

    CO2 emissions from soils are 10 times higher than anthropogenic CO2 emissions from fossil burning with around 60 Pg C a-1. At the same time around 60 Pg of carbon is added to the soils as litter from roots and leaves. Thus, the balance between both fluxes is supposed to be zero for the global earth system in steady state without human perturbations. However, the global carbon flux has been altered by humans since thousands of years by extracting biomass carbon as food, feed and fiber with global estimate of 40% of net primary productivity (NPP). This fraction is low in forests but agricultural systems, in particular croplands, are systems with a high net exported carbon fraction. Soils are mainly input driven systems. Agricultural soils depend on input to compensate directly for i) respiration losses, ii) extraction of carbon (and nitrogen) and depletion (e.g. via manure) or indirectly via enhances NPP (e.g. via fertilization management). In a literature review we examined the role of biomass extraction and carbon input via roots, crop residues and amendments (manure, slurry etc.) to agricultural soil's carbon stocks. Recalcitrance of biomass carbon was found to be of minor importance for long-term carbon storage. Thus, also the impact of crop type on soil carbon dynamics seems mainly driven by the amount of crop residuals of different crop types. However, we found distinct differences in the efficiency of C input to refill depleted soil C stocks between above ground C input or below ground root litter C input, with root-C being more efficient due to slower turnover rates. We discuss the role of different measures to decrease soil carbon turnover (e.g. decreased tillage intensity) as compared to measures that increase C input (e.g. cover crops) in the light of global developments in agricultural management with ongoing specialization and segregation between catch crop production and dairy farms.

  14. A cost-efficient method to assess carbon stocks in tropical peat soil

    Directory of Open Access Journals (Sweden)

    M. W. Warren

    2012-06-01

    Full Text Available Estimation of soil carbon stocks in tropical wetlands requires costly laboratory analyses and suitable facilities, which are often lacking in developing nations where most tropical wetlands are found. It is therefore beneficial to develop simple yet robust analytical tools to assess soil carbon stocks where financial and technical limitations are common. Here we use published and original data to describe soil carbon density (gC cm−3; Cd as a function of bulk density (g dry soil cm−3; Bd, which can be used to estimate belowground carbon storage using Bd measurements only. Predicted carbon densities and stocks are compared with those obtained from direct carbon analysis for ten peat swamp forest stands in three national parks of Indonesia. Analysis of soil carbon density and bulk density from the literature indicated a strong linear relationship (Cd = Bd × 0.49 + 4.61, R2 = 0.96, n = 94 for soils with an organic C content >40%. As organic C content decreases, the relationship between Cd and Bd becomes less predictable as soil texture becomes an important determinant of Cd. The equation predicted soil C stocks to within 0.39% to 7.20% of observed values. When original data were included in the analysis, the revised equation: Cd = Bd × 0.48 + 4.28, R2 = 0.96, n = 678 was well within the 95% confidence intervals of the original equation, and tended to decrease Cd estimates slightly. We recommend this last equation for a rapid estimation of soil C stocks for well developed peat soils where C content >40%.

  15. What Influences Stock Market Reaction to Sukuk Issues? The Impact of Scholars and Sukuk Types

    OpenAIRE

    Christophe Godlewski; Rima Turk-Ariss; Laurent Weill

    2014-01-01

    Sukuk, the shari’a-compliant alternative mode of financing to conventional bonds, have considerably expanded over the last decade. We analyze the stock market reaction to two key features of sukuk: type and characteristics of the shari’a scholar certifying the issue. We use the event study methodology to measure abnormal returns for a sample of 131 sukuk from eight countries over the period 2006-2013 and find that Ijara sukuk structures exert a positive influence on the stock price of the iss...

  16. Soil organic carbon of European forest soils: current stock and projections under climate change conditions

    Science.gov (United States)

    Caddeo, Antonio; Marras, Serena; Spano, Donatella; Sirca, Costantino

    2016-04-01

    Soil organic carbon (SOC) represents the largest terrestrial carbon pool, and it is subjected to climate change impacts. In Europe, a limited number of studies makes a wide-scale comparison of SOC stock and changes under climate change conditions, and most of them are related to agricultural soils. In this work, the SOC stock of the forested areas of Europe (obtained from the CORINE 2006 Land Use Map) was assessed at 1 km resolution using the agro-ecosystem SOC model CENTURY. The results of the model were compared with independent observational datasets (i.e. LUCAS Topsoil Survey Database). In addition, climate simulations (RCPs 4.5 and 8.5) using the CMCC (Euro-Mediterranean Centre on Climate Change) and the CORDEX dataset were used to estimate the SOC changes of these areas under climate change conditions.

  17. Soil Carbon and Nitrogen Stocks of Different Hawaiian Sugarcane Cultivars

    Directory of Open Access Journals (Sweden)

    Rebecca Tirado-Corbalá

    2015-06-01

    Full Text Available Sugarcane has been widely used as a biofuel crop due to its high biological productivity, ease of conversion to ethanol, and its relatively high potential for greenhouse gas reduction and lower environmental impacts relative to other derived biofuels from traditional agronomic crops. In this investigation, we studied four sugarcane cultivars (H-65-7052, H-78-3567, H-86-3792 and H-87-4319 grown on a Hawaiian commercial sugarcane plantation to determine their ability to store and accumulate soil carbon (C and nitrogen (N across a 24-month growth cycle on contrasting soil types. The main study objective establish baseline parameters for biofuel production life cycle analyses; sub-objectives included (1 determining which of four main sugarcane cultivars sequestered the most soil C and (2 assessing how soil C sequestration varies among two common Hawaiian soil series (Pulehu-sandy clay loam and Molokai-clay. Soil samples were collected at 20 cm increments to depths of up to 120 cm using hand augers at the three main growth stages (tillering, grand growth, and maturity from two experimental plots at to observe total carbon (TC, total nitrogen (TN, dissolved organic carbon (DOC and nitrates (NO−3 using laboratory flash combustion for TC and TN and solution filtering and analysis for DOC and NO−3. Aboveground plant biomass was collected and subsampled to determine lignin and C and N content. This study determined that there was an increase of TC with the advancement of growing stages in the studied four sugarcane cultivars at both soil types (increase in TC of 15–35 kg·m2. Nitrogen accumulation was more variable, and NO−3 (<5 ppm were insignificant. The C and N accumulation varies in the whole profile based on the ability of the sugarcane cultivar’s roots to explore and grow in the different soil types. For the purpose of storing C in the soil, cultivar H-65-7052 (TC accumulation of ~30 kg·m−2 and H-86-3792 (25 kg·m−2 rather H-78

  18. Changes in soil carbon stocks in Brazil due to land use: paired site comparisons and a regional pasture soil survey

    Science.gov (United States)

    Assad, E. D.; Pinto, H. S.; Martins, S. C.; Groppo, J. D.; Salgado, P. R.; Evangelista, B.; Vasconcellos, E.; Sano, E. E.; Pavão, E.; Luna, R.; Camargo, P. B.; Martinelli, L. A.

    2013-10-01

    In this paper we calculated soil carbon stocks in Brazil studying 17 paired sites where soil stocks were determined in native vegetation, pastures and crop-livestock systems (CPS), and in other regional samplings encompassing more than 100 pasture soils, from 6.58 to 31.53° S, involving three major Brazilian biomes: Cerrado, Atlantic Forest, and the Pampa. The average native vegetation soil carbon stocks at 10, 30 and 60 cm soil depth were equal to approximately 29, 64, and 92 Mg ha-1, respectively. In the paired sites, carbon losses of 7.5 Mg ha-1 and 11.6 Mg ha-1 in CPS systems were observed at 10 cm and 30 cm soil depths, respectively. In pasture soils, carbon losses were similar and equal to 7.5 Mg ha-1 and 11.0 Mg ha-1 at 10 cm and 30 cm soil depths, respectively. Differences at 60 cm soil depth were not significantly different between land uses. The average soil δ13C under native vegetation at 10 and 30 cm depth were equal to -25.4‰ and -24.0‰, increasing to -19.6‰ and -17.7‰ in CPS, and to -18.9‰, and -18.3‰ in pasture soils, respectively; indicating an increasing contribution of C4 carbon in these agrosystems. In the regional survey of pasture soils, the soil carbon stock at 30 cm was equal to approximately 51 Mg ha-1, with an average δ13C value of -19.67‰. Key controllers of soil carbon stock in pasture sites were sand content and mean annual temperature. Collectively, both could explain approximately half of the variance of soil carbon stocks. When pasture soil carbon stocks were compared with the average soil carbon stocks of native vegetation estimated for Brazilian biomes and soil types by Bernoux et al. (2002) there was a carbon gain of 6.7 Mg ha-1, which is equivalent to a carbon gain of 15% compared to the carbon soil stock of the native vegetation. The findings of this study are consistent with differences found between regional comparisons like our pasture sites and plot-level paired study sites in estimating soil carbon stocks

  19. Consolidating and updating estimates of northern peatland extents and carbon stocks

    Science.gov (United States)

    Hugelius, G.; Loisel, J.; MacDonald, G. M.; Jackson, R. B.; Treat, C. C.; Turetsky, M. R.; Yu, Z.

    2015-12-01

    Conditions favoring peat accumulation have been particularly prevalent in boreal and subarctic regions. The large pool of organic carbon accumulated in Northern peatlands has been an important component in the global carbon cycle throughout the Holocene. All northern peatlands store an estimated 440 Pg organic carbon while a separate study estimates that permafrost region peatlands store ca. 300 Pg organic carbon. However, the degree of overlap between these studies remains unclear and there are differences in methodologies and definitions which prevent direct harmonization of estimates. Here we address this problems by (1) compiling several different databases of field observation data and by (2) comparing previously estimated northern peatland areal extents to the extents of organic soils estimated from compiled harmonized regional and national soil maps from the northern mid and high latitudes. Organic soils are by definition peatlands with >40 cm of near surface peat. The combined estimated extent of organic soils in these maps is 3.44 million km2. This is very similar to the spatial extents of Northern peatlands derived from various national peat resource inventories as reported by previous studies. Our results show that roughly one third of this organic soil area is in permafrost. Based on newly compiled databases we provide spatially distributed estimates of peatland depth and stocks of peat carbon across different biomes. These analyses reveal significant differences in peat depth and carbon stocks between peatland regions and between non-permafrost and permafrost peatlands.

  20. The microbe-mediated mechanisms affecting topsoil carbon stock in Tibetan grasslands

    OpenAIRE

    Yue, Haowei; Wang, Mengmeng; Wang, Shiping; Gilbert, Jack A.; Sun, Xin; Wu, Linwei; Lin, Qiaoyan; Hu, Yigang; Li, Xiangzhen; He, Zhili; Zhou, Jizhong; Yang, Yunfeng

    2015-01-01

    Warming has been shown to cause soil carbon (C) loss in northern grasslands owing to accelerated microbial decomposition that offsets increased grass productivity. Yet, a multi-decadal survey indicated that the surface soil C stock in Tibetan alpine grasslands remained relatively stable. To investigate this inconsistency, we analyzed the feedback responses of soil microbial communities to simulated warming by soil transplant in Tibetan grasslands. Whereas microbial functional diversity decrea...

  1. An inventory-based approach for estimating the managed China's forest biomass carbon stock

    Science.gov (United States)

    Huang, M.; Yu, G.; Yue, X.; Wang, J.

    2014-12-01

    China's forests cover a large area and have the characteristics of young age thus have the potential for a major role in mitigate the rate of global climate change. On the basis of forest inventory data and spatial distribution of forest stand age and forest type, we developed an approach for estimating yearly China's forest biomass carbon stocks change. Using this approach, we estimated the changes of forest carbon stock due to management practice and forest age structure change, respectively, and predicted China's future carbon potential based on national forest expansion plan. We also discussed sustainable harvesting intensity for the expanded forest of 2020. The spatial pattern of forest biomass carbon density in 2001 showed high in southwestern and northeastern areas, and low in the other regions, meanwhile the high C sinks appeared in the southwestern and northeastern young-aged forests and low in the southwestern and northeastern old-aged forests. The total forest biomass C stock of China increased from 6.06 Pg C in 2001 to 7.88 Pg C in 2013, giving a total increase of 1.82 Pg C, in which 0.45 Pg C is caused by forest expansion. The average C sink during 2002-2013 was 151.83 Tg C, in which 75.5% is the results of forest growth and 24.5% is caused by forest expansion. With the assumption of China's forest area will expand by 40 million hectares from 2006 to 2020, the forest C stock in 2020 is predicted as 9.04 Pg C. Harvesting intensity experiments conducted on the expanded forest of 2020 shown higher harvesting level will lead to decline in forest biomass in long term. The harvesting level of 2% is an optimal harvesting intensity for sustainable development of China's forest resources.

  2. Effect of sugarcane harvesting systems on soil carbon stocks in Brazil : an examination of existing data

    OpenAIRE

    Cerri, C. C.; Galdos, M. V.,; Maia, S. M. F.; Bernoux, Martial; Feigl, B. J.,; Powlson, D.; Cerri, C. E. P.

    2011-01-01

    Agricultural management practices that promote net carbon (C) accumulation in the soil have been considered as an important potential mitigation option to combat global warming. The change in the sugarcane harvesting system, to one which incorporates C into the soil from crop residues, is the focus of this work. The main objective was to assess and discuss the changes in soil organic C stocks caused by the conversion of burnt to unburnt sugarcane harvesting systems in Brazil, when considering...

  3. 110 Years of change in urban tree stocks and associated carbon storage

    OpenAIRE

    Díaz-Porras, D.F; Evans, K.L.; Gaston, K J

    2014-01-01

    Understanding the long-term dynamics of urban vegetation is essential in determining trends in the provision of key resources for biodiversity and ecosystem services and improving their management. Such studies are, however, extremely scarce due to the lack of suitable historical data. We use repeat historical photographs from the 1900s, 1950s, and 2010 to assess general trends in the quantity and size distributions of the tree stock in urban Sheffield and resultant aboveground carbon storage...

  4. Estimation of biomass and carbon stocks: the case of the Atlantic Forest

    OpenAIRE

    Vieira, Simone Aparecida; Alves, Luciana Ferreira; Aidar, Marcos; Araujo, Luciana Spinelli; Baker, Tim; Batista, Joao Luis Ferreira; Campos, Mariana Cruz; Camargo, Plinio Barbosa; Chave, Jerome; Delitti, Welington Braz Carvalho; Higuchi, Niro; Honorio, Euridice; Joly, Carlos Alfredo; Keller, Michael; Martinelli, Luiz Antonio

    2008-01-01

    The main objective of this paper is to present and discuss the best methods to estimate live above ground biomass in the Atlantic Forest. The methods presented and conclusions are the products of a workshop entitled "Estimation of Biomass and Carbon Stocks: the Case of Atlantic Rain Forest". Aboveground biomass (AGB) in tropical forests is mainly contained in trees. Tree biomass is a function of wood volume, obtained from the diameter and height, architecture and wood density (dry weight per ...

  5. The Intergenerational Transfer of Solar Radiation Management Capabilities and Atmospheric Carbon Stocks

    OpenAIRE

    Goeschl, Timo; Heyen, Daniel; Moreno-Cruz, Juan

    2013-01-01

    Solar radiation management (SRM) technologies are considered one of the likeliest forms of geoengineering. If developed, a future generation could deploy them to limit the damages caused by the atmospheric carbon stock inherited from the current generation, despite their negative side effects. Should the current generation develop these geoengi-neering capabilities for a future generation? And how would a decision to develop SRM impact on the current generation's abatement efforts? Natural sc...

  6. Impact of tropical land use change on soil organic carbon stocks ? a meta-analysis

    OpenAIRE

    Don, Axel; Schumacher, Jens; Freibauer, Annette

    2010-01-01

    Abstract Land use changes are the second largest source of human induced greenhouse gas emission, mainly due to deforestation in the tropics and sub-tropics. CO2 emissions result from biomass and soil organic carbon (SOC) losses and may be offset with afforestation programs. However, the effect of land use changes on SOC is poorly quantified due to insufficient data quality (only SOC concentrations and no SOC stocks, shallow sampling depth) and representativeness. In a global meta-...

  7. Ground cover rice production system facilitates soil carbon and nitrogen stocks at regional scale

    Directory of Open Access Journals (Sweden)

    M. Liu

    2015-02-01

    Full Text Available Rice production is increasingly challenged by irrigation water scarcity, however covering paddy rice soils with films (ground cover rice production system: GCRPS can significantly reduce water demand as well as overcome temperature limitations at the beginning of the vegetation period resulting in increased grain yields in colder regions of rice production with seasonal water shortages. It has been speculated that the increased soil aeration and temperature under GCRPS may result in losses of soil organic carbon and nitrogen stocks. Here we report on a regional scale experiment, conducted by sampling paired adjacent Paddy and GCRPS fields at 49 representative sites in the Shiyan region, which is typical for many mountainous areas across China. Parameters evaluated included soil C and N stocks, soil physical and chemical properties, potential carbon mineralization rates, fractions of soil organic carbon and stable carbon isotopic composition of plant leaves. Furthermore, root biomass was quantified at maximum tillering stage at one of our paired sites. Against expectations the study showed that: (1 GCRPS significantly increased soil organic C and N stocks 5–20 years following conversion of production systems, (2 there were no differences between GCRPS and Paddy in soil physical and chemical properties for the various soil depths with the exception of soil bulk density, (3 GCRPS had lower mineralization potential for soil organic C compared with Paddy over the incubation period, (4 GCRPS showed lower δ15N in the soils and plant leafs indicating less NH3 volatilization in GCRPS than in Paddy; and (5 GCRPS increased yields and root biomass in all soil layers down to 40 cm depth. Our results suggest that GCRPS is an innovative rice production technique that not only increases yields using less irrigation water, but that it also is environmentally beneficial due to increased soil C and N stocks at regional scale.

  8. Influence of the Investor's Behavior on the Complexity of the Stock Market

    Science.gov (United States)

    Atman, A. P. F.; Gonçalves, Bruna Amin

    2012-04-01

    One of the pillars of the finance theory is the efficient-market hypothesis, which is used to analyze the stock market. However, in recent years, this hypothesis has been questioned by a number of studies showing evidence of unusual behaviors in the returns of financial assets ("anomalies") caused by behavioral aspects of the economic agents. Therefore, it is time to initiate a debate about the efficient-market hypothesis and the "behavioral finances." We here introduce a cellular automaton model to study the stock market complexity, considering different behaviors of the economical agents. From the analysis of the stationary standard of investment observed in the simulations and the Hurst exponents obtained for the term series of stock index, we draw conclusions concerning the complexity of the model compared to real markets. We also investigate which conditions of the investors are able to influence the efficient market hypothesis statements.

  9. Ecosystem carbon stocks and their changes in China’s grasslands

    Institute of Scientific and Technical Information of China (English)

    Anwar; MOHAMMAT

    2010-01-01

    The knowledge of carbon(C) stock and its dynamics is crucial for understanding the role of grassland ecosystems in China’s terrestrial C cycle.To date,a comprehensive assessment on C balance in China’s grasslands is still lacking.By reviewing published literature,this study aims to evaluate ecosystem C stocks(both vegetation biomass and soil organic C) and their changes in China’s grasslands.Our results are summarized as follows:(1) biomass C density(C stock per area) of China’s grasslands differed greatly among previous studies,ranging from 215.8 to 348.1 g C m-2 with an average of 300.2 g C m-2.Likewise,soil C density also varied greatly between 8.5 and 15.1 kg C m-2.In total,ecosystem C stock in China’s grasslands was estimated at 29.1 Pg C.(2) Both the magnitude and direction of ecosystem C changes in China’s grasslands differed greatly among previous studies.According to recent reports,neither biomass nor soil C stock in China’s grasslands showed a significant change during the past 20 years,indicating that grassland ecosystems are C neutral.(3) Spatial patterns and temporal dynamics of grassland biomass were closely correlated with precipitation,while changes in soil C stocks exhibited close associations with soil moisture and soil texture.Human activities,such as livestock grazing and fencing could also affect ecosystem C dynamics in China’s grasslands.

  10. A framework for assessing global change risks to forest carbon stocks in the United States.

    Directory of Open Access Journals (Sweden)

    Christopher W Woodall

    Full Text Available Among terrestrial environments, forests are not only the largest long-term sink of atmospheric carbon (C, but are also susceptible to global change themselves, with potential consequences including alterations of C cycles and potential C emission. To inform global change risk assessment of forest C across large spatial/temporal scales, this study constructed and evaluated a basic risk framework which combined the magnitude of C stocks and their associated probability of stock change in the context of global change across the US. For the purposes of this analysis, forest C was divided into five pools, two live (aboveground and belowground biomass and three dead (dead wood, soil organic matter, and forest floor with a risk framework parameterized using the US's national greenhouse gas inventory and associated forest inventory data across current and projected future Köppen-Geiger climate zones (A1F1 scenario. Results suggest that an initial forest C risk matrix may be constructed to focus attention on short- and long-term risks to forest C stocks (as opposed to implementation in decision making using inventory-based estimates of total stocks and associated estimates of variability (i.e., coefficient of variation among climate zones. The empirical parameterization of such a risk matrix highlighted numerous knowledge gaps: 1 robust measures of the likelihood of forest C stock change under climate change scenarios, 2 projections of forest C stocks given unforeseen socioeconomic conditions (i.e., land-use change, and 3 appropriate social responses to global change events for which there is no contemporary climate/disturbance analog (e.g., severe droughts in the Lake States. Coupling these current technical/social limits of developing a risk matrix to the biological processes of forest ecosystems (i.e., disturbance events and interaction among diverse forest C pools, potential positive feedbacks, and forest resiliency/recovery suggests an operational

  11. Whole-island carbon stocks in the tropical Pacific: implications for mangrove conservation and upland restoration.

    Science.gov (United States)

    Donato, D C; Kauffman, J B; Mackenzie, R A; Ainsworth, A; Pfleeger, A Z

    2012-04-30

    Management of forest carbon (C) stocks is an increasingly prominent land-use issue. Knowledge of carbon storage in tropical forests is improving, but regional variations are still poorly understood, and this constrains forest management and conservation efforts associated with carbon valuation mechanisms (e.g., carbon markets). This deficiency is especially pronounced in tropical islands and low-lying coastal areas where climate change impacts are expected to be among the most severe. This study presents the first field estimate of island-wide carbon storage in ecosystems of Oceania, with special attention to the regional role of coastal mangroves, which occur on islands and coastal zones throughout the tropics. On two island groups of Micronesia (Yap and Palau), we sampled all above- and belowground C pools, including soil and vegetation, in 24 sites distributed evenly among the three major vegetation structural types: mangroves, upland forests, and open savannas (generally on degraded lands formerly forested). Total C stocks were estimated to be 3.9 and 15.2 Tg C on Yap and Palau, respectively. Mangroves contained by far the largest per-hectare C pools (830-1218 Mg C ha(-1)), with deep organic-rich soils alone storing more C (631-754 Mg C ha(-1)) than all pools combined in upland systems. Despite covering just 12-13% of land area, mangroves accounted for 24-34% of total island C stocks. Savannas (156-203 Mg C ha(-1)) contained significantly lower C stocks than upland forests (375-437 Mg C ha(-1)), suggesting that reforesting savannas where appropriate has high potential for carbon-based funding to aid restoration objectives. For mangroves, these results demonstrate the key role of these systems within the broader context of C storage in island and coastal landscapes. Sustainable management of mangrove forests and their large C stocks is of high importance at the regional scale, and climate change mitigation programs such as REDD+ could play a large role in

  12. Soil type-depending effect of paddy management: Organic carbon distribution and stocks

    Science.gov (United States)

    Kölbl, Angelika; Drechsler, Susanne; Wissing, Livia; Schad, Peter; Rahayu Utami, Sri; Cao, Zhihong; Kögel-Knabner, Ingrid

    2013-04-01

    Paddy soils may originate from many different types of soil but are highly modified by human activities. These soils are mostly managed under submerged conditions, a management which is assumed to favour carbon sequestration. Therefore, the present study aims to investigate the impact of paddy management on soil organic carbon distributions and stocks in major soil types that are typically used for rice cultivation in Asia. Fluvisol and Acrisol sites (sub-tropical monsoon climate, PR China) as well as Andosol, Vertisol and Ferralsol sites (tropical climate of Java, Indonesia) were compared, as they represent a large range of soil properties to be expected in Asian paddy fields. Paddy rice at all of these sites is cultivated under flooded conditions followed by an upland crop. To evaluate the impact of paddy management, paddy soils as well as adjacent agricultural soils which are not used for paddy rice production (non-paddy soils) were chosen. At each site, three soil profiles of paddy and non-paddy soils were sampled horizontally. All samples were analysed for bulk density and organic carbon (OC) concentrations, and the corresponding OC stocks were calculated. Paddy soils derived from Fluvisols and Acrisols(PR China) showed clearly higher OC concentrations in the topsoils, leading to higher cumulative OC stocks in paddy soils compared to the respective non-paddy soils. However, other soil types did not show the expected higher OC sequestration under paddy management. For example, paddy soils derived from Ferralsols and Vertisols of Java are characterised by very similar OC concentrations and OC stocks as compared to their respective non-paddy soils. Also paddy and non-paddy soils derived from Andosols (Java) showed similar OC concentrations and depth distributions; only the slightly higher bulk density values under paddy management lead to slightly higher OC stocks in these soils. As clearly shown by our results, we cannot necessarily assume that rice production

  13. Carbon stock and humification index of organic matter affected by sugarcane straw and soil management

    Directory of Open Access Journals (Sweden)

    Aline Segnini

    2013-10-01

    Full Text Available The maintenance of sugarcane (Saccharum spp. straw on a soil surface increases the soil carbon (C stocks, but at lower rates than expected. This fact is probably associated with the soil management adopted during sugarcane replanting. This study aimed to assess the impact on soil C stocks and the humification index of soil organic matter (SOM of adopting no-tillage (NT and conventional tillage (CT for sugarcane replanting. A greater C content and stock was observed in the NT area, but only in the 0-5 cm soil layer (p < 0.05. Greater soil C stock (0-60 cm was found in soil under NT, when compared to CT and the baseline. While C stock of 116 Mg ha-1 was found in the baseline area, in areas under CT and NT systems the values ranged from 120 to 127 Mg ha-1. Carbon retention rates of 0.67 and 1.63 Mg C ha-1 year-1 were obtained in areas under CT and NT, respectively. Laser-Induced Fluorescence Spectroscopy showed that CT makes the soil surface (0-20 cm more homogeneous than the NT system due to the effect of soil disturbance, and that the SOM humification index (H LIF is larger in CT compared to NT conditions. In contrast, NT had a gradient of increasing H LIF, showing that the entry of labile organic material such as straw is also responsible for the accumulation of C in this system. The maintenance of straw on the soil surface and the adoption of NT during sugarcane planting are strategies that can increase soil C sequestration in the Brazilian sugarcane sector.

  14. Carbon Stock Assessment Using Remote Sensing and Forest Inventory Data in Savannakhet, Lao PDR

    Directory of Open Access Journals (Sweden)

    Phutchard Vicharnakorn

    2014-06-01

    Full Text Available Savannakhet Province, Lao People’s Democratic Republic (PDR, is a small area that is connected to Thailand, other areas of Lao PDR, and Vietnam via road No. 9. This province has been increasingly affected by carbon dioxide (CO2 emitted from the transport corridors that have been developed across the region. To determine the effect of the CO2 increases caused by deforestation and emissions, the total above-ground biomass (AGB and carbon stocks for different land-cover types were assessed. This study estimated the AGB and carbon stocks (t/ha of vegetation and soil using standard sampling techniques and allometric equations. Overall, 81 plots, each measuring 1600 m2, were established to represent samples from dry evergreen forest (DEF, mixed deciduous forest (MDF, dry dipterocarp forest (DDF, disturbed forest (DF, and paddy fields (PFi. In each plot, the diameter at breast height (DBH and height (H of the overstory trees were measured. Soil samples (composite n = 2 were collected at depths of 0–30 cm. Soil carbon was assessed using the soil depth, soil bulk density, and carbon content. Remote sensing (RS; Landsat Thematic Mapper (TM image was used for land-cover classification and development of the AGB estimation model. The relationships between the AGB and RS data (e.g., single TM band, various vegetation indices (VIs, and elevation were investigated using a multiple linear regression analysis. The results of the total carbon stock assessments from the ground data showed that the MDF site had the highest value, followed by the DEF, DDF, DF, and PFi sites. The RS data showed that the MDF site had the highest area coverage, followed by the DDF, PFi, DF, and DEF sites. The results indicated significant relationships between the AGB and RS data. The strongest correlation was found for the PFi site, followed by the MDF, DDF, DEF, and DF sites.

  15. Carbon stock changes of forest land in Finland under different levels of wood use and climate change

    OpenAIRE

    Sievänen, Risto; Salminen, Olli; Lehtonen, Aleksi; Ojanen, Paavo; Liski, Jari; Ruosteenoja, Kimmo; Tuomi, Mikko

    2014-01-01

    & Context Prediction of the effect of harvests and climate change (CC) on the changes in carbon stock of forests is necessary both for CC mitigation and adaptation purposes. & Aims We assessed the impact of roundwood and fuelwood removals and climate change (CC) on the changes in carbon stock of Finnish forests during 2007–2042. We considered three harvest scenarios: two based on the recent projections of roundwood and fuelwood demand, and the third reflecting the maximum sustainable cutting ...

  16. A comparison of soil organic carbon stock in ancient and modern land use systems in Denmark

    DEFF Research Database (Denmark)

    Breuning-Madsen, Henrik; Elberling, Bo; Balstrøm, Thomas;

    2009-01-01

    comparison of the organic matter content in these mound cores and the plough layer in modern farmland offers an opportunity to compare the soil organic carbon (SOC) stocks in ancient and modern land use systems and to evaluate the long-term trends in carbon (C) sequestration in relation to modern farmland......During the South Scandinavian Early Bronze Age about 3300 years ago, thousands of burial mounds were constructed of sods from fallow ground used for grazing in Denmark and northern Germany. In some of these mounds a wet, anaerobic core developed, preventing the decomposition of organic matter. A...

  17. Carbon Stock Potential of Oak and Pine Forests in Garhwal Region in Indian Central Himalayas

    OpenAIRE

    Nanda Nautiyal; Vir Singh

    2013-01-01

    Oak (Quercus leucotichophora) and pine (Pinus roxburghii) are the two most dominant forest types occurring in Indian Central Himalayas. CO2 mitigation potential of these two forest types was observed in the present study. Carbon stock densities for AGTB, BB, LHG, DWS, AGSB and SOC were estimated and higher values were recorded in oak forest stands. Total carbon density estimated was 2420.54 Mg/ha for oak forest of Gopeshwar and 986.93 Mg/ha for pine forest of Nandprayag. CO2 mitigation potent...

  18. The impact of bryophytes on the carbon stocks of northern boreal forest soils

    Science.gov (United States)

    Hagemann, U.; Moroni, M. T.; Shaw, C. H.; Kurz, W. A.

    2012-04-01

    Dead organic matter (DOM), organic layer, and mineral soil carbon (C) dynamics in cool and humid northern boreal forests are expected to differ from those of drier or warmer boreal forests, because processes such as paludification and woody debris (WD) burial within the organic layer by overgrowing moss are more pronounced in regions with low average temperatures, vigorous moss layers, and long fire-return intervals. However, very few studies have provided field-measured data for these mostly remote regions. Hence, C cycling models such as the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3) have rarely been validated with field data from northern boreal forest soils, resulting in large uncertainties for estimated C stocks in a large proportion of the boreal forest ecozone. We present (i) measured data on organic layer and mineral soil (0-45 cm) C stocks in 18 old-growth and disturbed high-boreal black spruce stands in Labrador, Canada; (ii) a comparison of field-measured soil C stocks with those predicted using the CBM-CFS3; and (iii) special characteristics of the DOM and soil C dynamics of northern boreal forest soils that require modifications of model parameters and structure. Measured organic layer C stocks (30.4-47.4 Mg C ha-1) were within the range reported for other boreal forests. However, mineral soil C stocks (121.5-208.1 Mg C ha-1) contributed 58-76% to total ecosystem C stocks. Mineral soil C stocks were thus considerably higher than observed in other upland boreal forests in drier or warmer regions, but similar to values reported for black spruce on poorly drained sites and peat soils. In addition, large amounts of deadwood C (4.7-18.2 Mg C ha-1) were found to be buried within the organic layer, contributing up to 31% to total organic layer C stocks. The comparison of field-measured and CBM-CFS3 modeled C stocks showed that organic layer and mineral soil DOM in Labrador black spruce stands likely decays at lower rates than assumed by CBM

  19. Refining soil organic carbon stock estimates for China’s palustrine wetlands

    Science.gov (United States)

    Ma, Kun; Liu, Junguo; Zhang, Ying; Parry, Lauren E.; Holden, Joseph; Ciais, Philippe

    2015-12-01

    Palustrine wetlands (PWs) include all bogs, fens, swamps and marshes that are non-saline and which are not lakes or rivers. They therefore form a highly important group of wetlands which hold large carbon stocks. If these wetlands are not protected properly they could become a net carbon source in the future. Compilation of spatially explicit wetland databases, national inventory data and in situ measurement of soil organic carbon (SOC) could be useful to better quantify SOC and formulate long-term strategies for mitigating global climate change. In this study, a synergistic mapping approach was used to create a hybrid map for PWs for China and to estimate their SOC content. Total SOC storage in PWs was estimated to be 4.3 ± 1.4 Pg C, with a SOC density of 31.17 (±10.55) kg C m-2 in the upper 1 m of the soil layer. This carbon stock is concentrated in Northeast China (49%) and the Qinghai-Tibet Plateau (41%). Given the large pool of carbon stored in PWs compared to other soil types, we suggest that urgent monitoring programmes on SOC should be established in regions with very few datasets, but where PWs appear to be common such as the Tibet region and Northwest China.

  20. Ground cover rice production systems increase soil carbon and nitrogen stocks at regional scale

    Science.gov (United States)

    Liu, M.; Dannenmann, M.; Lin, S.; Saiz, G.; Yan, G.; Yao, Z.; Pelster, D. E.; Tao, H.; Sippel, S.; Tao, Y.; Zhang, Y.; Zheng, X.; Zuo, Q.; Butterbach-Bahl, K.

    2015-08-01

    Rice production is increasingly limited by water scarcity. Covering paddy rice soils with films (so-called ground cover rice production system: GCRPS) can significantly reduce water demand as well as overcome temperature limitations at the beginning of the growing season, which results in greater grain yields in relatively cold regions and also in those suffering from seasonal water shortages. However, it has been speculated that both increased soil aeration and temperature under GCRPS result in lower soil organic carbon and nitrogen stocks. Here we report on a regional-scale experiment conducted in Shiyan, a typical rice-producing mountainous area of China. We sampled paired adjacent paddy and GCRPS fields at 49 representative sites. Measured parameters included soil carbon (C) and nitrogen (N) stocks (to 1 m depth), soil physical and chemical properties, δ15N composition of plants and soils, potential C mineralization rates, and soil organic carbon (SOC) fractions at all sampling sites. Root biomass was also quantified at one intensively monitored site. The study showed that: (1) GCRPS increased SOC and N stocks 5-20 years following conversion from traditional paddy systems; (2) there were no differences between GCRPS and paddy systems in soil physical and chemical properties for the various soil depths, with the exception of soil bulk density; (3) GCRPS increased above-ground and root biomass in all soil layers down to a 40 cm depth; (4) δ15N values were lower in soils and plant leaves indicating lower NH3 volatilization losses from GCRPS than in paddy systems; and (5) GCRPS had lower C mineralization potential than that observed in paddy systems over a 200-day incubation period. Our results suggest that GCRPS is an innovative production technique that not only increases rice yields using less irrigation water, but that it also increases SOC and N stocks.

  1. 110 Years of change in urban tree stocks and associated carbon storage.

    Science.gov (United States)

    Díaz-Porras, Daniel F; Gaston, Kevin J; Evans, Karl L

    2014-04-01

    Understanding the long-term dynamics of urban vegetation is essential in determining trends in the provision of key resources for biodiversity and ecosystem services and improving their management. Such studies are, however, extremely scarce due to the lack of suitable historical data. We use repeat historical photographs from the 1900s, 1950s, and 2010 to assess general trends in the quantity and size distributions of the tree stock in urban Sheffield and resultant aboveground carbon storage. Total tree numbers declined by a third from the 1900s to the 1950s, but increased by approximately 50% from the 1900s-2010, and by 100% from the 1950s-2010. Aboveground carbon storage in urban tree stocks had doubled by 2010 from the levels present in the 1900s and 1950s. The initial decrease occurred at a time when national and regional tree stocks were static and are likely to be driven by rebuilding following bombing of the urban area during the Second World War and by urban expansion. In 2010, trees greater than 10 m in height comprised just 8% of those present. The increases in total tree numbers are thus largely driven by smaller trees and are likely to be associated with urban tree planting programmes. Changes in tree stocks were not constant across the urban area but varied with the current intensity of urbanization. Increases from 1900 to 2010 in total tree stocks, and smaller sized trees, tended to be greatest in the most intensely urbanized areas. In contrast, the increases in the largest trees were more marked in areas with the most green space. These findings emphasize the importance of preserving larger fragments of urban green space to protect the oldest and largest trees that contribute disproportionately to carbon storage and other ecosystem services. Maintaining positive trends in urban tree stocks and associated ecosystem service provision will require continued investment in urban tree planting programmes in combination with additional measures, such as

  2. A cost-efficient method to assess carbon stocks in tropical peat soil

    Directory of Open Access Journals (Sweden)

    M. W. Warren

    2012-11-01

    Full Text Available Estimation of belowground carbon stocks in tropical wetland forests requires funding for laboratory analyses and suitable facilities, which are often lacking in developing nations where most tropical wetlands are found. It is therefore beneficial to develop simple analytical tools to assist belowground carbon estimation where financial and technical limitations are common. Here we use published and original data to describe soil carbon density (kgC m−3; Cd as a function of bulk density (gC cm−3; Bd, which can be used to rapidly estimate belowground carbon storage using Bd measurements only. Predicted carbon densities and stocks are compared with those obtained from direct carbon analysis for ten peat swamp forest stands in three national parks of Indonesia. Analysis of soil carbon density and bulk density from the literature indicated a strong linear relationship (Cd = Bd × 495.14 + 5.41, R2 = 0.93, n = 151 for soils with organic C content > 40%. As organic C content decreases, the relationship between Cd and Bd becomes less predictable as soil texture becomes an important determinant of Cd. The equation predicted belowground C stocks to within 0.92% to 9.57% of observed values. Average bulk density of collected peat samples was 0.127 g cm−3, which is in the upper range of previous reports for Southeast Asian peatlands. When original data were included, the revised equation Cd = Bd × 468.76 + 5.82, with R2 = 0.95 and n = 712, was slightly below the lower 95% confidence interval of the original equation, and tended to decrease Cd estimates. We recommend this last equation for a rapid estimation of soil C stocks for well-developed peat soils where C content > 40%.

  3. Responses of aboveground and belowground forest carbon stocks to disturbances in boreal forests of Northeastern China

    Science.gov (United States)

    Huang, Chao; He, Hong S.; Hawbaker, Todd J.; Liang, Yu; Gong, Peng; Wu, Wuzhiwei; Zhu, Zhiliang

    2016-04-01

    Boreal forests represents about 1/3 of forest area and 1/3 of forest carbon on earth. Carbon dynamics of boreal forests are sensitive to climate change, natural (e.g., fire) and anthropogenic (e.g., harvest) disturbances. Field-based studies suggest that disturbances alter species composition, stand structure, and litter decomposition, and have significant effects on boreal forest carbon dynamics. Most of these studies, however, covered a relatively short period of time (e.g., few decades), which is limited in revealing such long-term effects of disturbances. Models are therefore developed as important tools in exploring the long-term (e.g., hundreds of years) effects of disturbances on forest carbon dynamics. In this study, we applied a framework of coupling forest ecosystem and landscape model to evaluating the effect of fire, harvest and their interactions on carbon stocks in a boreal forest landscape of Northeastern China. We compared the simulation results under fire, harvest and fire-harvest interaction scenarios with the simulated value of succession scenario at 26 landtypes over 150 years at a 10-year time step. Our results suggest that aboveground and belowground carbon are significantly reduced by fire and harvest over 150years. Fire reduced aboveground carbon by 2.3±0.6 ton/ha, harvest by 6.0±1.4 ton/ha, and fire and harvest interaction by 8.0±1.9 tons/ha. Fire reduced belowground carbon by 4.6±3.4 ton/ha, harvest by 5.0±3.5 ton/ha, and fire-harvest interaction by 5.7±3.7 tons/ha. The divergent response of carbon stocks among landtypes and between disturbance scenarios was due to the spatial interactions between fire, harvest, and species composition. Our results indicated that boreal forests carbon stocks prediction needs to consider the effects of fire and harvest for improving the estimation accuracy.

  4. Carbon stocks of different land uses in the Kumrat valley, Hindu Kush Region of Pakistan

    Institute of Scientific and Technical Information of China (English)

    Adnan Ahmad; Syed Moazzam Nizami

    2015-01-01

    Changes in land use cover, particularly from forest to agriculture, is a major contributing factor in increasing carbon dioxide (CO2) level in the atmosphere. Using satellite images of 1999 and 2011, land use and land use changes in the Kumrat valley KPK, Pakistan, were determined:a net decrease of 11.56 and 7.46%occurred in forest and rangeland, while 100% increase occurred in agriculture land (AL). Biomass in different land uses, forest land (FL), AL, and range land (RL) was determined by field inventory. From the biomass data, the amount of carbon was calculated, considering 50%of the biomass as carbon. Soil carbon was also determined to a depth of 0–15 and 16–30 cm. The average carbon stocks (C stocks) in all land uses ranged from 28.62 ± 13.8 t ha-1 in AL to 486.6 ± 32.4 t ha-1 in pure Cedrus deodara forest. The results of the study confirmed that forest soil and vegeta-tion stored the maximum amount of carbon followed by RL. Conversion of FL and RL to AL not only leads to total loss of about 56% (from FL conversion) and 37% (RL conversion) of soil carbon in the last decades but also the loss of a valuable carbon sink. In order to meet the emis-sions reduction obligations of the Kyoto Protocol, Con-servation of forest and RL in the mountainous regions of the Hindu Kush will help Pakistan to meet its emissions reduction goals under the Kyoto Protocol.

  5. Temperature response functions introduce high uncertainty in modelled carbon stocks in cold temperature regimes

    Directory of Open Access Journals (Sweden)

    H. Portner

    2009-08-01

    Full Text Available Models of carbon cycling in terrestrial ecosystems contain formulations for the dependence of respiration on temperature, but the sensitivity of predicted carbon pools and fluxes to these formulations and their parameterization is not understood. Thus, we made an uncertainty analysis of soil organic matter decomposition with respect to its temperature dependency using the ecosystem model LPJ-GUESS.

    We used five temperature response functions (Exponential, Arrhenius, Lloyd-Taylor, Gaussian, Van't Hoff. We determined the parameter uncertainty ranges of the functions by nonlinear regression analysis based on eight experimental datasets from northern hemisphere ecosystems. We sampled over the uncertainty bounds of the parameters and run simulations for each pair of temperature response function and calibration site. The uncertainty in both long-term and short-term soil carbon dynamics was analyzed over an elevation gradient in southern Switzerland.

    The function of Lloyd-Taylor turned out to be adequate for modelling the temperature dependency of soil organic matter decomposition, whereas the other functions either resulted in poor fits (Exponential, Arrhenius or were not applicable for all datasets (Gaussian, Van't Hoff. There were two main sources of uncertainty for model simulations: (1 the uncertainty in the parameter estimates of the response functions, which increased with increasing temperature and (2 the uncertainty in the simulated size of carbon pools, which increased with elevation, as slower turn-over times lead to higher carbon stocks and higher associated uncertainties. The higher uncertainty in carbon pools with slow turn-over rates has important implications for the uncertainty in the projection of the change of soil carbon stocks driven by climate change, which turned out to be more uncertain for higher elevations and hence higher latitudes, which are of key importance for the global terrestrial carbon

  6. The Ability Of Mangrove Areas To Conserves Carbon Stock In Semi Arid Region

    Directory of Open Access Journals (Sweden)

    Aah Ahmad Almulqu

    2015-02-01

    Full Text Available ABSTRACT Above ground trees and poles biomass was estimated in Avicennie marina Rhizophora stylosa and Sonneratia alba of mangrove forest in Oebelo Central Kupang Regency East Nusa Tenggara Indonesia. The research was conducted from January 2013 to July 2013 and undestructive method was used trees and poles which having a diameter of less than 5 cm and over. Choosing the allometric equation based on the difficulties and practicality to get variable in the field become considerations. Results shows that carbon stock pattern different between all of trees and poles and increasing ranging of diameter will followed of biomass and carbon stock in all trees and poles. Species that contributed the largest amount of carbon was Sonneratia alba with the total carbon stored in all individuals of this species of about 59 of the total biomass stored on the research areas. This species had high number of individuals high average of diameter and height. At areas of research Sonneratia alba shared a maximum of 59 of the total biomass while Rhizophora stylosa and Avicennia marina shared 38 and 3 respectively.

  7. Current and potential carbon stocks in Moso bamboo forests in China.

    Science.gov (United States)

    Li, Pingheng; Zhou, Guomo; Du, Huaqiang; Lu, Dengsheng; Mo, Lufeng; Xu, Xiaojun; Shi, Yongjun; Zhou, Yufeng

    2015-06-01

    Bamboo forests provide important ecosystem services and play an important role in terrestrial carbon cycling. Of the approximately 500 bamboo species in China, Moso bamboo (Phyllostachys pubescens) is the most important one in terms of distribution, timber value, and other economic values. In this study, we estimated current and potential carbon stocks in China's Moso bamboo forests and in their products. The results showed that Moso bamboo forests in China stored about 611.15 ± 142.31 Tg C, 75% of which was in the top 60 cm soil, 22% in the biomass of Moso bamboos, and 3% in the ground layer (i.e., bamboo litter, shrub, and herb layers). Moso bamboo products store 10.19 ± 2.54 Tg C per year. The potential carbon stocks reach 1331.4 ± 325.1 Tg C, while the potential C stored in products is 29.22 ± 7.31 Tg C a(-1). Our results indicate that Moso bamboo forests and products play a critical role in C sequestration. The information gained in this study will facilitate policy decisions concerning carbon sequestration and management of Moso bamboo forests in China. PMID:25836664

  8. Carbon and Nitrogen Stocks in the Salt Lake Valley Urban Ecosystem

    Science.gov (United States)

    Williamson, J. C.; Dennison, P. E.; Ehleringer, J. R.

    2008-12-01

    Water availability exerts a fundamental control over primary production processes in both managed and unmanaged arid land ecosystems. Societal interest in converting grasslands to urban forest has likely increased primary productivity in many western US cities. The changes in primary productivity have the potential to alter C and N stocks of urban soils. Here, we report on trends in soil C and N storage observed along an urban age gradient spanning a century in the Salt Lake Valley, USA metropolitan area. Our results indicate substantial accumulation of soil organic C and total N beneath residential lawns in this semi-arid region. Soil organic C and total N stocks in the upper 20 cm of lawn soils increased as much as 3-fold following long-term residential use. Average tree biomass of residential parcels increased quickly with age, creating urban forests with standing biomass values similar to nearby coniferous forests. Anthropogenic influence emerged as the dominant source of variation in these stocks across our study area, eclipsing site characteristics such as soil texture and elevation that are commonly important in natural settings. While US cities are prominent exporters of atmospheric C and reactive N, significant gains in C and N stocks may offset a portion of these outputs in well-irrigated cities in dry climates. Observations of regional C and N storage in western US cities should lead to better estimates of sequestration capacities and provide insights into the potential consequence of future water-use policies, including xeriscaping.

  9. Environmental controls on soil organic carbon and nitrogen stocks in the high-altitude arid western Qinghai-Tibetan Plateau permafrost region

    Science.gov (United States)

    Wu, Xiaodong; Zhao, Lin; Fang, Hongbing; Zhao, Yuguo; Smoak, Joseph M.; Pang, Qiangqiang; Ding, Yongjian

    2016-01-01

    While permafrost in the circum-Artic has great influence on soil organic carbon (SOC) and total nitrogen (TN) stocks, this might not be the case in low-latitude arid permafrost regions. We test this hypothesis in the western Qinghai-Tibetan Plateau (QTP) permafrost region. Fifty-nine soil profiles were analyzed to examine the SOC and TN distribution and the controlling factors in western QTP, which is a desert steppe ecoregion. Mean stocks of SOC (5.29 kg m-2) and TN (0.56 kg m-2) for the top 200 cm in this area were lower than those of the east QTP and circum-Arctic regions. The SOC and TN stocks under vegetative cover with permafrost conditions were significantly higher than those of desert conditions. The SOC and TN stocks for the layers of different depths were related to the content of clay, silt, and moisture. Although the active layer thickness (ALT) had a significant negative correlation to soil moisture, the ALT explained little or no variance in the SOC and TN stocks. The results showed that in the vast permafrost regions of the western QTP, the SOC and TN stocks are very low, and the main controlling factors for the SOC and TN are soil texture, moisture, and vegetation type. The SOC pool in this area may not be as vulnerable to degradation associated with climate warming and thus not emit greenhouse gases at the same rate as other permafrost regions. The different response of the SOC in this region should be considered in carbon cycling models.

  10. Implications of Using USDA-NCSS Bulk Density to Estimate Carbon Stocks in Forest Soils Across the Southeastern United States

    Science.gov (United States)

    Bacon, A. R.; Akers, K.; Cucinella, J.; Grunwald, S.; Jokela, E. J.; Markewitz, D.; Laviner, M. A.; Vogel, J. G.; Martin, T.; Fox, T. D.; Kane, M.; Peter, G. F.; Davis, J. M.; Ross, C. W.

    2015-12-01

    Estimates of soil bulk density (Db) are critical for accurate estimates of soil carbon (C) stocks, and thus, greatly influence the balance and interpretation of soil C budgets at plot, regional, and national scales. Large scale soil C investigations in the United States (US) almost always utilize a compilation of more than 20,000 Db observations across the US within the USDA-NRCS National Cooperative Soil Survey (NCSS) database. NCSS observations can be manually extracted as point data and then stratified or modeled by a variety of soil taxonomic, geographic, and environmental factors to estimate Db across large scales. NCSS observations also underpin the popular Soil Survey Geographic (SSURGO) database which provides continuous Db estimates across most of the US. Here, for the first time, we evaluate the precision and accuracy with which NCSS data can estimate forest soil Db across the southeastern United States and explore how using these observations impacts soil C budgets in forests across the region. We analyze and compare nearly 3,000 Db observations from the NCSS database to nearly 1,500 Db observations from the PINEMAP Tier II Network (325 experimental forest plots) across the southeastern US. We model all NCSS observations and 70% of the PINEMAP Tier II observations (a calibration dataset) separately with Random Forest algorithms to create a variety of Db predictive models at 0-10, 10-20, 20-50, and 50-100 cm depths. We validate all models against 30% of the PINEMAP Tier II observations (a validation dataset). As indexed by the mean prediction error (MPE), NCSS observations tend to over predict forest soil Db across the validation dataset by an average of 0.20 g/cc. Incorporating this positive bias of NCSS Db predictions into C stock estimates in the top 100 cm of soil across the PINEMAP Tier II network inflates C stock estimates by an average of 13 Mg/ha. Our findings identify significant potential for NCSS observations to over predict soil Db, and thus

  11. Conventional tillage vs. organic farming in relation to soil organic carbon stock in olive groves in Mediterranean rangelands (Southern Spain

    Directory of Open Access Journals (Sweden)

    L. Parras-Alcántara

    2014-01-01

    Full Text Available Soil organic carbon (SOC concentration is a soil variable subject to changes. In agricultural soils, the management system is a key factor that influence to these changes. For determine the management system effects on SOC stocks (SOC-S in olive groves, 114 soil profiles were studied in the Los Pedroches Valley (Mediterranean rangelands – southern Spain for long-term (20 yr. The management practices were conventional tillage (CT and organic farming (OF in four soil types: Cambisols (CM, Regosols (RG, Luvisols (LV and Leptosols (LP. Soil properties were statistically analyzed by management techniques, soil types and horizons. The principal components analyses identified four factors that explained 65% of the variance. Also, significant differences (p p 2 in all studied soils. These results indicate high soils quality, and that management practices affect to SOC store in the Los Pedroches Valley.

  12. Land-cover effects on soil organic carbon stocks in a European city.

    Science.gov (United States)

    Edmondson, Jill L; Davies, Zoe G; McCormack, Sarah A; Gaston, Kevin J; Leake, Jonathan R

    2014-02-15

    Soil is the vital foundation of terrestrial ecosystems storing water, nutrients, and almost three-quarters of the organic carbon stocks of the Earth's biomes. Soil organic carbon (SOC) stocks vary with land-cover and land-use change, with significant losses occurring through disturbance and cultivation. Although urbanisation is a growing contributor to land-use change globally, the effects of urban land-cover types on SOC stocks have not been studied for densely built cities. Additionally, there is a need to resolve the direction and extent to which greenspace management such as tree planting impacts on SOC concentrations. Here, we analyse the effect of land-cover (herbaceous, shrub or tree cover), on SOC stocks in domestic gardens and non-domestic greenspaces across a typical mid-sized U.K. city (Leicester, 73 km(2), 56% greenspace), and map citywide distribution of this ecosystem service. SOC was measured in topsoil and compared to surrounding extra-urban agricultural land. Average SOC storage in the city's greenspace was 9.9 kg m(-2), to 21 cm depth. SOC concentrations under trees and shrubs in domestic gardens were greater than all other land-covers, with total median storage of 13.5 kg m(-2) to 21 cm depth, more than 3 kg m(-2) greater than any other land-cover class in domestic and non-domestic greenspace and 5 kg m(-2) greater than in arable land. Land-cover did not significantly affect SOC concentrations in non-domestic greenspace, but values beneath trees were higher than under both pasture and arable land, whereas concentrations under shrub and herbaceous land-covers were only higher than arable fields. We conclude that although differences in greenspace management affect SOC stocks, trees only marginally increase these stocks in non-domestic greenspaces, but may enhance them in domestic gardens, and greenspace topsoils hold substantial SOC stores that require protection from further expansion of artificial surfaces e.g. patios and driveways. PMID

  13. Sustainable influence of social media on volatility of stock prices. State of art

    OpenAIRE

    Dubko Anna Vladimirovna; Boissier Quentin

    2015-01-01

    The paper introduces the growing interest toward social media from investment funds. Article discusses the most vivid examples of social media influence on volatility of stock prices that stimulated the practical interest toward the problem. Also the paper reviews the existing academic researches. In the end it presents the authors’ model of the factors, defining the influential power of the message in the social media.

  14. Soil carbon and nitrogen stocks in forests along an altitudinal gradient in the eastern Himalayas and a meta-analysis of global data.

    Science.gov (United States)

    Tashi, Sonam; Singh, Balwant; Keitel, Claudia; Adams, Mark

    2016-06-01

    High-altitude soils potentially store a large pool of carbon (C) and nitrogen (N). The assessment of total C and N stocks in soils is vital to understanding the C and N dynamics in terrestrial ecosystems. In this study, we examined effects of altitude and forest composition on soil C and N along a transect from 317 to 3300 m a.s.l. in the eastern Himalayas. We used meta-analysis to establish the context for our results on the effects of altitude on soil C, including variation with depth. Total C and N contents of soils significantly increased with altitude, but decreased with soil depth. Carbon and N were similarly correlated with altitude and temperature, and temperature was seemingly the main driver of soil C along the altitudinal gradient. Altitude accounted for 73% of the variation in C and 47% of the variation in N stocks. Soil pH and cation exchange capacity were correlated with both soil C and N stocks. Increases in soil C and N stocks were related to forest composition, forest basal area as well as quantity of leaf litter that were in turn influenced by altitude and temperature. Concentrations of C in foliage increased by 2.1% for every 1000 m rise in altitude, while that in leaf litter increased by 2.3%. PMID:26840803

  15. Taking Stock of Circumboreal Forest Carbon With Ground Measurements, Airborne and Spaceborne LiDAR

    Science.gov (United States)

    Neigh, Christopher S. R.; Nelson, Ross F.; Ranson, K. Jon; Margolis, Hank A.; Montesano, Paul M.; Sun, Guoqing; Kharuk, Viacheslav; Naesset, Erik; Wulder, Michael A.; Andersen, Hans-Erik

    2013-01-01

    The boreal forest accounts for one-third of global forests, but remains largely inaccessible to ground-based measurements and monitoring. It contains large quantities of carbon in its vegetation and soils, and research suggests that it will be subject to increasingly severe climate-driven disturbance. We employ a suite of ground-, airborne- and space-based measurement techniques to derive the first satellite LiDAR-based estimates of aboveground carbon for the entire circumboreal forest biome. Incorporating these inventory techniques with uncertainty analysis, we estimate total aboveground carbon of 38 +/- 3.1 Pg. This boreal forest carbon is mostly concentrated from 50 to 55degN in eastern Canada and from 55 to 60degN in eastern Eurasia. Both of these regions are expected to warm >3 C by 2100, and monitoring the effects of warming on these stocks is important to understanding its future carbon balance. Our maps establish a baseline for future quantification of circumboreal carbon and the described technique should provide a robust method for future monitoring of the spatial and temporal changes of the aboveground carbon content.

  16. Species diversity, biomass, and carbon stock assessments of a natural mangrove forest in palawan, philippines

    International Nuclear Information System (INIS)

    Philippines claims international recognition for its mangrove-rich ecosystem which play significant functions from the viewpoint of ecosystem services and climate change mitigation. In this study, we assessed the species diversity of the natural mangrove forest of Bahile, Puerto Princesa City, Palawan and evaluated its potential to sequester and store carbon. Sixteen plots with a size of 10 m * 10 m were established using quadrat sampling technique to identify, record, and measure the trees. Diversity index and allometric equations were utilized to determine species diversity, and biomass and carbon stocks. Sediment samples in undisturbed portions using a 30 cm high and 5 cm diameter corer were collected in all plots to determine near-surface sediment carbon. The diversity index (H = 0.9918) was very low having a total of five true mangrove species identified dominated by Rhizophora apiculata Bl. with an importance value index of 148.1%. Among the stands, 74% of the total biomass was attributed to the above-ground (561.2 t ha-1) while 26% was credited to the roots (196.5 t ha-1). The total carbon sequestered and stored in the above-ground and root biomass were 263.8 t C ha-1 (50%) and 92.3 t C ha-1 (17%), respectively. Sediments contained 33% (173.75 t C ha-1) of the mangrove C-stocks. Stored carbon was equivalent to 1944.5 t CO/sub 2/ ha-1. These values suggest that Bahile natural mangrove forest has a potential to sequester and store substantial amounts of atmospheric carbon, hence the need for sustainable management and protection of this important coastal ecosystem. (author)

  17. Organic carbon and total nitrogen stocks in soils of the Lena River Delta

    Directory of Open Access Journals (Sweden)

    S. Zubrzycki

    2012-12-01

    Full Text Available The Lena River Delta, which is the largest delta in the Arctic, extends over an area of 32 000 km2 and likely holds more than half of the entire soil organic carbon mass stored in the seven major deltas in the northern permafrost regions. The geomorphic units of the Lena River Delta which were formed by true deltaic sedimentation processes are a Holocene river terrace and the active floodplains. Their mean soil organic carbon stocks for the upper 1 m of soils were estimated at 29 kg m−2 ± 10 kg m−2 and at 14 kg m−2 ± 7 kg m−2, respectively. For the depth of 1 m, the total soil organic carbon pool of the Holocene river terrace was estimated at 121 Tg ± 43 Tg, and the soil organic carbon pool of the active floodplains was estimated at 120 Tg ± 66 Tg. The mass of soil organic carbon stored within the observed seasonally thawed active layer was estimated at about 127 Tg assuming an average maximum active layer depth of 50 cm. The soil organic carbon mass which is stored in the perennially frozen ground below 50 cm soil depth, which is excluded from intense biogeochemical exchange with the atmosphere, was estimated at 113 Tg. The mean nitrogen (N stocks for the upper 1 m of soils were estimated at 1.2 kg m−2 ± 0.4 kg m−2 for the Holocene river terrace and at 0.9 kg m−2 ± 0.4 kg m−2 for the active floodplain levels, respectively. For the depth of 1 m, the total N pool of the river terrace was estimated at 4.8 Tg ± 1.5 Tg, and the total N pool of the floodplains was estimated at 7.7 Tg ± 3.6 Tg. Considering the projections for deepening of the seasonally thawed active layer up to 120 cm in the Lena River Delta region within the 21st century, these large carbon and nitrogen stocks could become increasingly available for decomposition and mineralization processes.

  18. Estimating Forest Carbon Stock in Alpine and Arctic Ecotones of the Urals

    Directory of Open Access Journals (Sweden)

    V. A. Usoltsev

    2014-10-01

    Full Text Available This paper reports on measured carbon stocks in the forests of two tree line ecotones of the Ural region where climate change might improve growing conditions. The first is an alpine ecotone that is represented by an altitudinal gradient of the spruce-dominated forests on the Western slope of the Tylaiskii Kamen Mountain (Western part of the Konzhakovskii-Tylaiskii-Serebryanskii Mountain system, 59°30′N, 59°00′E, at the alpine timber line that has risen from 864 to 960 m above sea level in the course of the last 100 years. The second is an arctic ecotone in larch-dominated forests at the lower course of the Pur river (67°N, 78°E, at the transition zone between closed floodplain forests and open or island-like communities of upland forests on tundra permafrost. According to our results, there are large differences in the carbon of the aboveground biomass of both ecotones across environmental gradients. In the alpine tree line ecotone, a 19-fold drop of the carbon stocks was detected between the lower and higher altitudinal levels. In the arctic ecotone the aboveground biomass carbon stock of forests of similar densities (1300 to 1700 trees per ha was 7 times as much in the river flood bed, and 5 times as much in mature, dense forests as the low density forests at higher elevations. Twelve regression equations describing dependencies of the aboveground tree biomass (stems, branches, foliage, total aboveground part upon stem diameter of the tree are proposed, which can be used to estimating the biological productivity (carbon of spruce and larch forests on Tylaiskii Kamen Mountain and the lower Pur river and on surrounding areas on the base of traditional forest mensuration have been proposed. In order to reduce the labor intensity of a coming determination of forest biomass the average values of density and dry matter content in the biomass fractions are given that were obtained by taking our sample trees.The results can be useful in

  19. Regional estimation of soil C stocks and CO2 emissions as influenced by cropping systems and soil type

    Science.gov (United States)

    Farina, Roberta; Marchetti, Alessandro; Di Bene, Claudia

    2015-04-01

    Soil organic matter (SOM) is of crucial importance for agricultural soil quality and fertility. At global level soil contains about three times the carbon stored in the vegetation and about twice that present in the atmosphere. Soil could act as source and sink of carbon, influencing the balance of CO2 concentration and consequently the global climate. The sink/source ratio depends on many factors that encompass climate, soil characteristics and different land management practices. Thus, the relatively large gross exchange of GHGs between atmosphere and soils and the significant stocks of carbon in soils, may have significant impact on climate and on soil quality. To quantify the dynamics of C induced by land cover change and the spatial and temporal dynamics of C sources and sinks at regional and, potentially, at national and global scales, we propose a methodology, based on a bio-physical model combined with a spatial explicit database to estimate C stock changes and emissions/removals. The study has been conducted in a pilot region in Italy (Apulia, Foggia province), considering the typical cropping systems of the area, namely rainfed cereals, tomato, vineyard and olives. For this purpose, the model RothC10N (Farina et al., 2013), that simulates soil C dynamics, has been modified to work directly in batch using data of climate, soil (over 290 georeferenced soil profiles), annual agriculture land use (1200 observations) The C inputs from crops have been estimated using statistics and data from literature. The model was run to equilibrium for each point of soil, in order to make all the data homogeneous in terms of time. The obtained data were interpolate with geostatisical procedures, obtaining a set of 30x30 km grid with the initial soil C. The new layer produced, together with soil and land use layers, were used for a long-term run (12 years). Results showed that olive groves and vineyards were able to stock a considerable amount of C (from 0.4 to 1.5 t ha-1 y

  20. A comparison of soil organic carbon stocks in Viking Age and modern land use systems in Denmark

    DEFF Research Database (Denmark)

    Breuning-Madsen, Henrik; Kristensen, J. Aa.; Holst, Mads Kähler;

    2013-01-01

    A comparison of the organic matter content in anaerobic soil horizons in burial mounds and the plough layer in modern farmlands offers a unique opportunity to compare the soil organic carbon (SOC) stocks in ancient and modern land use systems and to evaluate the long term carbon sequestration in...... manure, contain a SOC stock of roughly 60% of the level in the loamy Viking Age soils. The carbon loss since the Viking Age in the surrounding soils is believed to be due to liming and drainage that has increased the decomposition of organic matter in the soils. This loss can be balanced by present day...... ancient sandy soils, loamy soils surrounding the mounds and nation-wide soil surveys representing modern land use systems with low and high inputs of manure. Results show that within the upper 0.28 m of the soil, which is the average depth of present day plough-layers in Denmark, the carbon stock in the...

  1. The Dynamics, Ecological Variability and Estimated Carbon Stocks of Mangroves in Mahajamba Bay, Madagascar

    Directory of Open Access Journals (Sweden)

    Trevor G. Jones

    2015-08-01

    Full Text Available Mangroves are found throughout the tropics, providing critical ecosystem goods and services to coastal communities and supporting rich biodiversity. Globally, mangroves are being rapidly degraded and deforested at rates exceeding loss in many tropical inland forests. Madagascar contains around 2% of the global distribution, >20% of which has been deforested since 1990, primarily from over-harvest for forest products and conversion for agriculture and aquaculture. While historically not prominent, mangrove loss in Madagascar’s Mahajamba Bay is increasing. Here, we focus on Mahajamba Bay, presenting long-term dynamics calculated using United States Geological Survey (USGS national-level mangrove maps contextualized with socio-economic research and ground observations, and the results of contemporary (circa 2011 mapping of dominant mangrove types. The analysis of the USGS data indicated 1050 hectares (3.8% lost from 2000 to 2010, which socio-economic research suggests is increasingly driven by commercial timber extraction. Contemporary mapping results permitted stratified sampling based on spectrally distinct and ecologically meaningful mangrove types, allowing for the first-ever vegetation carbon stock estimates for Mahajamba Bay. The overall mean carbon stock across all mangrove classes was estimated to be 100.97 ± 10.49 Mg C ha−1. High stature closed-canopy mangroves had the highest average carbon stock estimate (i.e., 166.82 ± 15.28 Mg C ha−1. These estimates are comparable to other published values in Madagascar and elsewhere in the Western Indian Ocean and demonstrate the ecological variability of Mahajamba Bay’s mangroves and their value towards climate change mitigation.

  2. Soil organic carbon stock change by short rotation coppice cultivation on croplands

    Science.gov (United States)

    Walter, Katja; Don, Axel; Flessa, Heinz

    2013-04-01

    Bioenergy is a means to climate mitigation if the overall greenhouse gas balance of the respective crop is better than that of the replaced fossil fuel. The change in soil organic carbon (SOC) by land use change to bioenergy has to be integrated into the greenhouse gas balance. One promising way to provide biomass for energy purposes is the cultivation of fast growing trees in short rotation coppices (SRC), because their energy input is low compared to their energy output. Moreover, due to high litter input and no-till management we hypothesize that SOC is accumulating in SRC on the long term. To study this long term effect 18 old poplar and willow SRC plantations and adjacent croplands with the same land use history were sampled throughout Germany using a standardized sampling protocol with a sampling depth down to 80 cm. The age of SRC ranged from 8 to 35 years and they were harvested every 3 to 15 years. Soil organic carbon content, bulk density, pH value and texture were determined. The SOC stocks were calculated and corrected for equivalent soil masses. In the top 10 cm, SOC increased under poplar and willow plantations at all sites by 4.8 +/- 3.2 Mg ha-1, which is an accumulation rate of 0.3 Mg ha-1 a-1. Regarding the whole profile to 80 cm depth, the SOC change was not significant with 0.8 +/- 13.5 Mg ha-1. At 8 sites SOC stocks increased compared to the respective cropland, at 10 sites SOC stocks decreased (-18 Mg C ha-1 to +30 Mg C ha-1). The litter accumulation was low compared to afforestations, ranging from 0.4 Mg C ha-1 to 3.2 Mg C ha-1 which is a litter C accumulation rate of 0.2 Mg ha-1 a-1. Including the respective litter carbon, the average SOC accumulation rate was 0.1 ± 0.8 Mg C ha-1 a-1. Taking into account the large scatter of SOC stock changes among different sites, the hypothesis of long-term SOC accumulation by SRC cannot generally be confirmed. Nevertheless, SRC may substantially increase SOC if installed on carbon depleted croplands and

  3. Estimating Forest Carbon Stock in Alpine and Arctic Ecotones of the Urals

    OpenAIRE

    V. A. Usoltsev; V. P. Chasovskikh; О. А. Bogoslovskaya; Yu. V. Noritsina; V. А. Galako; G. G. Terekhov

    2014-01-01

    This paper reports on measured carbon stocks in the forests of two tree line ecotones of the Ural region where climate change might improve growing conditions. The first is an alpine ecotone that is represented by an altitudinal gradient of the spruce-dominated forests on the Western slope of the Tylaiskii Kamen Mountain (Western part of the Konzhakovskii-Tylaiskii-Serebryanskii Mountain system, 59°30′N, 59°00′E), at the alpine timber line that has risen from 864 to 960 m above sea level in t...

  4. Comparisons of allometric and climate-derived estimates of tree coarse root carbon stocks in forests of the United States

    OpenAIRE

    Russell, Matthew B.; Domke, Grant M.; Woodall, Christopher W; D’Amato, Anthony W.

    2015-01-01

    Background Refined estimation of carbon (C) stocks within forest ecosystems is a critical component of efforts to reduce greenhouse gas emissions and mitigate the effects of projected climate change through forest C management. Specifically, belowground C stocks are currently estimated in the United States’ national greenhouse gas inventory (US NGHGI) using nationally consistent species- and diameter-specific equations applied to individual trees. Recent scientific evidence has pointed to the...

  5. Soil, vegetation and total organic carbon stock development in self-restoring abandoned vineyards

    Science.gov (United States)

    József Novák, Tibor; Incze, József; Spohn, Marie; Giani, Luise

    2016-04-01

    Abandoned vineyard's soil and vegetation development was studied on Tokaj Nagy-Hill, which is one of the traditional wine-producing regions of Hungary, it is declared as UNESCO World Heritage site as cultural landscape. Spatial distribution and pattern of vineyards were changing during the last several hundreds of years, therefore significant part of abandoned vineyards were subjected to long-term spontaneous secondary succession of vegetation and self-restoration of soils in absence of later cultivation. Two chronosequences of spontaneously regenerating vineyard abandonments, one on south (S-sequence) and one on southwest (SW-sequence) slope with differing times since their abandonment (193, 142, 101, 63, 39 and 14 years), were compiled and studied. The S-sequence was 25-35% sloped and strongly eroded, and the SW-sequence was 17-25% sloped and moderately eroded. The sites were investigated in respect of vegetation characteristics, soil physico-chemical characteristics, total organic carbon stocks (TOC stocks), accumulation rates of total organic carbon (TOC accumulation rates), and soil profiles, which were classified according to the World Reference Base (WRB) 2014. Vegetation development resulted in shrub-grassland mosaics, supplemented frequently by protected forb species and forest development at the earliest abandonment in S-sequence, and predominantly to forest vegetation in SW-sequence, where trees were only absent at the 63 and 14 years old abandonment sites. In all sites soils on level of reference groups according to WRB were classified, and Cambisols, Regosols, Calcisols, Leptosols, Chernozems and Phaeozems were found. Soils of the S-sequence show shallow remnants of loess cover with colluvic and redeposited soil materials containing 15-65% skeletal volcanic rock of weathering products coated by secondary calcium carbonates. The SW-sequence profiles are developed on deep loess or loess derivatives. The calcium-carbonate content was higher in profiles of

  6. Soil carbon stock and soil characteristics at Tasik Chini Forest Reserve, Pahang, Malaysia

    Science.gov (United States)

    Nur Aqlili Riana, R.; Sahibin A., R.

    2015-09-01

    This study was carried out to determine soil carbon stock and soil characteristic at Tasik Chini Forest Reserve (TCFR), Pahang. A total of 10 (20 m x 25 m) permanent sampling plot was selected randomly within the area of TCFR. Soil samples were taken from all subplots using dutch auger based on soil depth of 0-20cm, 20-40cm, 40-60cm. Soil parameters determined were size distribution, soil water content, bulk density, organic matter, organic carbon content, pH and electrical conductivity. All parameters were determined following their respective standard methods. Results obtained showed that the soil in TCFR was dominated by clay texture (40%), followed by sandy clay loam (30%), loam (20%). Silty clay, clay loam and sandy loam constitutes about 10% of the soil texture. Range of mean percentage of organic matter and bulk density are from 2.42±0.06% to 11.64±0.39% and 1.01 to 1.04 (gcm-ł), respectively. Soil pH are relatively very acidic and mean of electrical conductivity is low. Soil carbon content ranged from 0.83±0.03 to 1.87±0.41%. All soil parameter showed a decreasing trend with depth except electrical conductivity. ANOVA test of mean percentage of organic matter, soil water content, soil pH and electrical conductivity showed a significant difference between plot (p0.05). There are no significant difference in mean percentage of soil water content, organic matter and bulk density between three different depth (p>0.05). There were a significant difference on percentage of soil carbon organic between plots and depth. The mean of soil organic carbon stock in soil to a depth of 60 cm calculated was 35.50 t/ha.

  7. Modelling carbon stocks and fluxes in the wood product sector: a comparative review.

    Science.gov (United States)

    Brunet-Navarro, Pau; Jochheim, Hubert; Muys, Bart

    2016-07-01

    In addition to forest ecosystems, wood products are carbon pools that can be strategically managed to mitigate climate change. Wood product models (WPMs) simulating the carbon balance of wood production, use and end of life can complement forest growth models to evaluate the mitigation potential of the forest sector as a whole. WPMs can be used to compare scenarios of product use and explore mitigation strategies. A considerable number of WPMs have been developed in the last three decades, but there is no review available analysing their functionality and performance. This study analyses and compares 41 WPMs. One surprising initial result was that we discovered the erroneous implementation of a few concepts and assumptions in some of the models. We further described and compared the models using six model characteristics (bucking allocation, industrial processes, carbon pools, product removal, recycling and substitution effects) and three model-use characteristics (system boundaries, model initialization and evaluation of results). Using a set of indicators based on the model characteristics, we classified models using a hierarchical clustering technique and differentiated them according to their increasing degrees of complexity and varying levels of user support. For purposes of simulating carbon stock in wood products, models with a simple structure may be sufficient, but to compare climate change mitigation options, complex models are needed. The number of models has increased substantially over the last ten years, introducing more diversity and accuracy. Calculation of substitution effects and recycling has also become more prominent. However, the lack of data is still an important constraint for a more realistic estimation of carbon stocks and fluxes. Therefore, if the sector wants to demonstrate the environmental quality of its products, it should make it a priority to provide reliable life cycle inventory data, particularly regarding aspects of time and

  8. Carbon stock assessment of three selected agroforestry systems in Bukidnon, Philippines

    Directory of Open Access Journals (Sweden)

    Mildred M. Labata

    2012-06-01

    Full Text Available Climate change, caused by global warming, is a phenomenon partly resulting from abundance of carbon dioxide in the atmosphere.It is the most pressing environmental problem of the world today. It persists, and it cannot be stopped. Rather, it can be mitigated. Agroforestrysystems as land use can reduce the atmospheric concentration of carbon dioxide. This study therefore aimed to generate data on the carbonstocks of three selected agroforestry systems located within the Province of Bukidnon. The methodologies used include measurement of treesat diameter breast height (dbh and sampling of herbaceous vegetation, litter, and soil for carbon content determination and farmer interview.Results showed that carbon accumulation of agroforestry systems goes along with the following order: taungya agroforestry system (174 MgCha-1 > mixed multistorey system (162 MgC ha-1 > falcata-coffee multistorey system (92 MgC ha-1. Carbon was stored in the various pools inthe following order of magnitude: soil (77-92% > trees (7-22% > herbaceous vegetation and litter (1%. Compared with natural forests, theseselected agroforestry systems represents 23-44% of the total carbon stock. Policy programs promoting the establishment of agroforestry systemsin idle lands in Bukidnon should be considered.

  9. Biomass carbon stocks and their changes in northern China’s grasslands during 1982-2006

    Institute of Scientific and Technical Information of China (English)

    Anwar; MOHAMMAT

    2010-01-01

    Grassland covers approximately one-third of the area of China and plays an important role in the global terrestrial carbon(C) cycle.However,little is known about biomass C stocks and dynamics in these grasslands.During 2001-2005,we conducted five consecutive field sampling campaigns to investigate above-and below-ground biomass for northern China’s grasslands.Using measurements obtained from 341 sampling sites,together with a NDVI(normalized difference vegetation index) time series dataset over 1982-2006,we examined changes in biomass C stock during the past 25 years.Our results showed that biomass C stock in northern China’s grasslands was estimated at 557.5 Tg C(1 Tg=1012 g),with a mean density of 39.5 g C m-2 for above-ground biomass and 244.6 g C m-2 for below-ground biomass.An increasing rate of 0.2 Tg C yr-1 has been observed over the past 25 years,but grassland biomass has not experienced a significant change since the late 1980s.Seasonal rainfall(January-July) was the dominant factor driving temporal dynamics in biomass C stock;however,the responses of grassland biomass to climate variables differed among various grassland types.Biomass in arid grasslands(i.e.,desert steppe and typical steppe) was significantly associated with precipitation,while biomass in humid grasslands(i.e.,alpine meadow) was positively correlated with mean January-July temperatures.These results suggest that different grassland ecosystems in China may show diverse responses to future climate changes.

  10. Soil carbon stocks and their rates of accumulation and loss in a boreal forest landscape

    Science.gov (United States)

    Rapalee, G.; Trumbore, S.E.; Davidson, E.A.; Harden, J.W.; Veldhuis, H.

    1998-01-01

    Boreal forests and wetlands are thought to be significant carbon sinks, and they could become net C sources as the Earth warms. Most of the C of boreal forest ecosystems is stored in the moss layer and in the soil. The objective of this study was to estimate soil C stocks (including moss layers) and rates of accumulation and loss for a 733 km2 area of the BOReal Ecosystem-Atmosphere Study site in northern Manitoba, using data from smaller-scale intensive field studies. A simple process-based model developed from measurements of soil C inventories and radiocarbon was used to relate soil C storage and dynamics to soil drainage and forest stand age. Soil C stocks covary with soil drainage class, with the largest C stocks occurring in poorly drained sites. Estimated rates of soil C accumulation or loss are sensitive to the estimated decomposition constants for the large pool of deep soil C, and improved understanding of deep soil C decomposition is needed. While the upper moss layers regrow and accumulate C after fires, the deep C dynamics vary across the landscape, from a small net sink to a significant source. Estimated net soil C accumulation, averaged for the entire 733 km2 area, was 20 g C m-2 yr-1 (28 g C m-2 yr-1 accumulation in surface mosses offset by 8 g C m-2 yr-1 lost from deep C pools) in a year with no fire. Most of the C accumulated in poorly and very poorly drained soils (peatlands and wetlands). Burning of the moss layer in only 1% of uplands would offset the C stored in the remaining 99% of the area. Significant interannual variability in C storage is expected because of the irregular occurrence of fire in space and time. The effects of climate change and management on fire frequency and on decomposition of immense deep soil C stocks are key to understanding future C budgets in boreal forests.

  11. Modelling the Carbon Stocks Estimation of the Tropical Lowland Dipterocarp Forest Using LIDAR and Remotely Sensed Data

    Science.gov (United States)

    Zaki, N. A. M.; Latif, Z. A.; Suratman, M. N.; Zainal, M. Z.

    2016-06-01

    Tropical forest embraces a large stock of carbon in the global carbon cycle and contributes to the enormous amount of above and below ground biomass. The carbon kept in the aboveground living biomass of trees is typically the largest pool and the most directly impacted by the anthropogenic factor such as deforestation and forest degradation. However, fewer studies had been proposed to model the carbon for tropical rain forest and the quantification still remain uncertainties. A multiple linear regression (MLR) is one of the methods to define the relationship between the field inventory measurements and the statistical extracted from the remotely sensed data which is LiDAR and WorldView-3 imagery (WV-3). This paper highlight the model development from fusion of multispectral WV-3 with the LIDAR metrics to model the carbon estimation of the tropical lowland Dipterocarp forest of the study area. The result shown the over segmentation and under segmentation value for this output is 0.19 and 0.11 respectively, thus D-value for the classification is 0.19 which is 81%. Overall, this study produce a significant correlation coefficient (r) between Crown projection area (CPA) and Carbon stocks (CS); height from LiDAR (H_LDR) and Carbon stocks (CS); and Crown projection area (CPA) and height from LiDAR (H_LDR) were shown 0.671, 0.709 and 0.549 respectively. The CPA of the segmentation found to be representative spatially with higher correlation of relationship between diameter at the breast height (DBH) and carbon stocks which is Pearson Correlation p = 0.000 (p DBH predictors to improve the inventory estimates of carbon using multiple linear regression method. The study concluded that the integration of WV-3 imagery with the CHM raster based LiDAR were useful in order to quantify the AGB and carbon stocks for a larger sample area of the Lowland Dipterocarp forest.

  12. Differences on soil organic carbon stock estimation according to sampling type in Mediterranean areas

    Science.gov (United States)

    Parras-Alcántara, Luis; Lozano-García, Beatriz

    2016-04-01

    Soil organic carbon (SOC) is an important part of the global carbon (C) cycle. In addition, SOC is a soil property subject to changes and highly variable in space and time. Consequently, the scientific community is researching the fate of the organic carbon in the ecosystems. In this line, soil organic matter configuration plays an important role in the Soil System (Parras-Alcántara and Lozano García, 2014). Internationally it is known that soil C sequestration is a strategy to mitigate climate change. In this sense, many soil researchers have studied this parameter (SOC). However, many of these studies were carried out arbitrarily using entire soil profiles (ESP) by pedogenetic horizons or soil control sections (SCS) (edaphic controls to different thickness). As a result, the indiscriminate use of both methodologies implies differences with respect to SOC stock (SOCS) quantification. This scenario has been indicated and warned for different researchers (Parras-Alcántara et al., 2015a; Parras-Alcántara et al., 2015b). This research sought to analyze the SOC stock (SOCS) variability using both methods (ESP and SCS) in the Cardeña and Montoro Natural Park (Spain). This nature reserve is a forested area with 385 km2 in southern Spain. Thirty-seven sampling points were selected in the study zone. Each sampling point was analyzed in two different ways, as ESP (by horizons) and as SCS with different depth increments (0-25, 25-50, 50-75 and 75-100 cm). The major goal of this research was to study the SOCS variability at regional scale. The studied soils were classified as Phaeozems, Cambisols, Regosols and Leptosols. The results obtained show an overestimation of SOCS when SCS sampling approach is used compared to ESP. This supports that methodology selection is very important to SOCS quantification. This research is an assessment for modeling SOCS at the regional level in Mediterranean natural areas. References Parras-Alcántara, L., Lozano-García, B., 2014

  13. Carbon stocks, tree diversity and their relation to soil properties in a Neotropical rainforest of South-East Mexico

    Science.gov (United States)

    Navarrete-Segueda, Armando; Siebe-Grabach, Christina; Ibarra-Manríquez, Guillermo; Martínez-Ramos, Miguel; Vázquez-Selem, Lorenzo

    2015-04-01

    Site heterogeneity at the local scale is an important factor for the generation of ecosystem services across the landscape. Several investigations at regional or local scale have identified the important role of soil properties and topography to determine tree diversity and productivity in tropical forests. We studied how the characteristics of soils affect the tree richness and carbon storage in the tropical rain forest of south-east Mexico. We compared carbon stocks on above-ground dry biomass of living trees, litter and soil organic carbon in 9 plots of 5000 m2 distributed in three contrasting soil-topographic units in neotropical forest (Floodplains/Low altitude hills/Steep slopes) all under the same climate. In each plot, landform features and soil properties to rooting depths were determined. We obtained richness and biomass values of trees with diameter at breast height (DBH) ≥ 10 cm. In each plot, litter and soil samples were taken for quantifying carbon in laboratory and allometric equations were applied to relate tree biomass (root and aerial) with carbon. We used cluster analysis as classification technique to compare richness between units. The relationship between soil properties and tree richness was obtained based on a canonical correspondence analysis. Both the classification and ordination techniques showed that plant diversity and richness respond to soil conditions. The variation was positively correlated with pH, total nitrogen, soil aeration, water retention capacity and exchange aluminum. The richness is smaller in floodplains, but this unit, with higher water and nutrient storage capacity, shows the largest carbon stocks. In contrast, limiting site for tree growth have less total carbon. Low altitude hills are much more heterogeneous in soil properties but also richer in tree species. The soil in this land unit has small rooting depth and available water holding capacity. Additionally, in this soil carbon stock is greater than the carbon

  14. Changes in Biomass Carbon and Soil Organic Carbon Stocks following the Conversion from a Secondary Coniferous Forest to a Pine Plantation.

    Science.gov (United States)

    Li, Shuaifeng; Su, Jianrong; Liu, Wande; Lang, Xuedong; Huang, Xiaobo; Jia, Chengxinzhuo; Zhang, Zhijun; Tong, Qing

    2015-01-01

    The objectives of this study were to estimate changes of tree carbon (C) and soil organic carbon (SOC) stock following a conversion in land use, an issue that has been only insufficiently addressed. For this study, we examined a chronosequence of 2 to 54-year-old Pinus kesiya var. langbianensis plantations that replaced the original secondary coniferous forest (SCF) in Southwest China due to clearing. C stocks considered here consisted of tree, understory, litter, and SOC (0-1 m). The results showed that tree C stocks ranged from 0.02±0.001 Mg C ha-1 to 141.43±5.29 Mg C ha-1, and increased gradually with the stand age. Accumulation of tree C stocks occurred in 20 years after reforestaion and C stock level recoverd to SCF. The maximum of understory C stock was found in a 5-year-old stand (6.74±0.7 Mg C ha-1) with 5.8 times that of SCF, thereafter, understory C stock decreased with the growth of plantation. Litter C stock had no difference excluding effects of prescribed burning. Tree C stock exhibited a significant decline in the 2, 5-year-old stand following the conversion to plantation, but later, increased until a steady state-level in the 20, 26-year-old stand. The SOC stocks ranged from 81.08±10.13 Mg C ha-1 to 160.38±17.96 Mg C ha-1. Reforestation significantly decreased SOC stocks of plantation in the 2-year-old stand which lost 42.29 Mg C ha-1 in the 1 m soil depth compared with SCF by reason of soil disturbance from sites preparation, but then subsequently recovered to SCF level. SOC stocks of SCF had no significant difference with other plantation. The surface profile (0-0.1 m) contained s higher SOC stocks than deeper soil depth. C stock associated with tree biomass represented a higher proportion than SOC stocks as stand development proceeded. PMID:26397366

  15. Carbon Stock Potential of Oak and Pine Forests in Garhwal Region in Indian Central Himalayas

    Directory of Open Access Journals (Sweden)

    Nanda Nautiyal

    2013-05-01

    Full Text Available Oak (Quercus leucotichophora and pine (Pinus roxburghii are the two most dominant forest types occurring in Indian Central Himalayas. CO2 mitigation potential of these two forest types was observed in the present study. Carbon stock densities for AGTB, BB, LHG, DWS, AGSB and SOC were estimated and higher values were recorded in oak forest stands. Total carbon density estimated was 2420.54 Mg/ha for oak forest of Gopeshwar and 986.93 Mg/ha for pine forest of Nandprayag. CO2 mitigation potential of oak forest of Gopeshwar was recorded to be 8,713.94 CO2e and of pine forests 3552.95 CO2e.

  16. Soil carbon stock change in the forests of Denmark between 1990 and 2008

    DEFF Research Database (Denmark)

    Callesen, Ingeborg; Stupak, Inge; Georgiadis, Petros;

    2015-01-01

    . SOC stocks decreased with increasing initial SOC content (except calcareous mineral soils), consistently with reports from other inventories of SOC change. Unlike coarse and medium textured soils, fine-textured soils (> 10% clay in subsoil) with less than 4.1% C in the 0–25 cm layer gained 2.1 ± 1......Soils of the forests in Denmark were sampled in permanent plots in 1990 (t1) and resampled (N = 124) in 2007–9 (t2). The soils were classified according to the carbon concentration in the uppermost mineral soil horizon (0–25 cm) at t1, and according to subsoil texture and presence or absence of Ca......CO3 in the subsoil. Soil organic carbon (SOC) stocks in forest floor + mineral soil (0–100 cm) at t2 had a median of 15.9 kg C m− 2 (range 4.1–68.9 kg C m− 2). There was no detectable overall change in SOC during the 18-year period, but different trends were observed within the subsoil texture classes...

  17. Landscape-scale analysis of aboveground tree carbon stocks affected by mountain pine beetles in Idaho

    Science.gov (United States)

    Bright, B. C.; Hicke, J. A.; Hudak, A. T.

    2012-12-01

    Bark beetle outbreaks kill billions of trees in western North America, and the resulting tree mortality can significantly impact local and regional carbon cycling. However, substantial variability in mortality occurs within outbreak areas. Our objective was to quantify landscape-scale effects of beetle infestations on aboveground carbon (AGC) stocks using field observations and remotely sensed data across a 5054 ha study area that had experienced a mountain pine beetle outbreak. Tree mortality was classified using multispectral imagery that separated green, red, and gray trees, and models relating field observations of AGC to LiDAR data were used to map AGC. We combined mortality and AGC maps to quantify AGC in beetle-killed trees. Thirty-nine per cent of the forested area was killed by beetles, with large spatial variability in mortality severity. For the entire study area, 40-50% of AGC was contained in beetle-killed trees. When considered on a per-hectare basis, 75-89% of the study area had >25% AGC in killed trees and 3-6% of the study area had >75% of the AGC in killed trees. Our results show that despite high variability in tree mortality within an outbreak area, bark beetle epidemics can have a large impact on AGC stocks at the landscape scale.

  18. Landscape-scale analysis of aboveground tree carbon stocks affected by mountain pine beetles in Idaho

    International Nuclear Information System (INIS)

    Bark beetle outbreaks kill billions of trees in western North America, and the resulting tree mortality can significantly impact local and regional carbon cycling. However, substantial variability in mortality occurs within outbreak areas. Our objective was to quantify landscape-scale effects of beetle infestations on aboveground carbon (AGC) stocks using field observations and remotely sensed data across a 5054 ha study area that had experienced a mountain pine beetle outbreak. Tree mortality was classified using multispectral imagery that separated green, red, and gray trees, and models relating field observations of AGC to LiDAR data were used to map AGC. We combined mortality and AGC maps to quantify AGC in beetle-killed trees. Thirty-nine per cent of the forested area was killed by beetles, with large spatial variability in mortality severity. For the entire study area, 40–50% of AGC was contained in beetle-killed trees. When considered on a per-hectare basis, 75–89% of the study area had >25% AGC in killed trees and 3–6% of the study area had >75% of the AGC in killed trees. Our results show that despite high variability in tree mortality within an outbreak area, bark beetle epidemics can have a large impact on AGC stocks at the landscape scale. (letter)

  19. Ecosystem carbon stocks and sequestration potential of federal lands across the conterminous United States.

    Science.gov (United States)

    Tan, Zhengxi; Liu, Shuguang; Sohl, Terry L; Wu, Yiping; Young, Claudia J

    2015-10-13

    Federal lands across the conterminous United States (CONUS) account for 23.5% of the CONUS terrestrial area but have received no systematic studies on their ecosystem carbon (C) dynamics and contribution to the national C budgets. The methodology for US Congress-mandated national biological C sequestration potential assessment was used to evaluate ecosystem C dynamics in CONUS federal lands at present and in the future under three Intergovernmental Panel on Climate Change Special Report on Emission Scenarios (IPCC SRES) A1B, A2, and B1. The total ecosystem C stock was estimated as 11,613 Tg C in 2005 and projected to be 13,965 Tg C in 2050, an average increase of 19.4% from the baseline. The projected annual C sequestration rate (in kilograms of carbon per hectare per year) from 2006 to 2050 would be sinks of 620 and 228 for forests and grasslands, respectively, and C sources of 13 for shrublands. The federal lands' contribution to the national ecosystem C budget could decrease from 23.3% in 2005 to 20.8% in 2050. The C sequestration potential in the future depends not only on the footprint of individual ecosystems but also on each federal agency's land use and management. The results presented here update our current knowledge about the baseline ecosystem C stock and sequestration potential of federal lands, which would be useful for federal agencies to decide management practices to achieve the national greenhouse gas (GHG) mitigation goal. PMID:26417074

  20. Carbon stock and its compartments in a subtropical oxisol under long-term tillage and crop rotation systems

    Directory of Open Access Journals (Sweden)

    Ben-Hur Costa de Campos

    2011-06-01

    Full Text Available Soil organic matter (SOM plays a crucial role in soil quality and can act as an atmospheric C-CO2 sink under conservationist management systems. This study aimed to evaluate the long-term effects (19 years of tillage (CT-conventional tillage and NT-no tillage and crop rotations (R0-monoculture system, R1-winter crop rotation, and R2- intensive crop rotation on total, particulate and mineral-associated organic carbon (C stocks of an originally degraded Red Oxisol in Cruz Alta, RS, Southern Brazil. The climate is humid subtropical Cfa 2a (Köppen classification, the mean annual precipitation 1,774 mm and mean annual temperature 19.2 ºC. The plots were divided into four segments, of which each was sampled in the layers 0-0.05, 0.05-0.10, 0.10-0.20, and 0.20-0.30 m. Sampling was performed manually by opening small trenches. The SOM pools were determined by physical fractionation. Soil C stocks had a linear relationship with annual crop C inputs, regardless of the tillage systems. Thus, soil disturbance had a minor effect on SOM turnover. In the 0-0.30 m layer, soil C sequestration ranged from 0 to 0.51 Mg ha-1 yr-1, using the CT R0 treatment as base-line; crop rotation systems had more influence on soil stock C than tillage systems. The mean C sequestration rate of the cropping systems was 0.13 Mg ha-1 yr-1 higher in NT than CT. This result was associated to the higher C input by crops due to the improvement in soil quality under long-term no-tillage. The particulate C fraction was a sensitive indicator of soil management quality, while mineral-associated organic C was the main pool of atmospheric C fixed in this clayey Oxisol. The C retention in this stable SOM fraction accounts for 81 and 89 % of total C sequestration in the treatments NT R1 and NT R2, respectively, in relation to the same cropping systems under CT. The highest C management index was observed in NT R2, confirming the capacity of this soil management practice to improve the soil C

  1. It’s more about the Content than the Users! The Influence of Social Broadcasting on Stock Markets

    DEFF Research Database (Denmark)

    Benthaus, Janek; Beck, Roman

    2015-01-01

    a large amount of stock-related information. This data is increasingly analyzed by research and practice to predict stock market developments. Insights from social broadcasting networks are used to support the decision-making process of investors and are integrated into automatic trading algorithms...... to react quickly to broadcasted information. However, a comprehensive understanding about the influence of social broadcasting networks on stock markets is missing. In this study, we address this gap by conceptualizing and empirically testing a model incorporating three dimensions of social...... broadcasting networks: users, messages, and discussion. We analyze 1.84 million stock-related Twitter messages concerning the S&P 100 companies between January and April 2014 and corresponding intraday stock market data from NYSE and NASDAQ. Our research model is constructed applying factor analyses and tested...

  2. Site Productivity and Forest Carbon Stocks in the United States: Analysis and Implications for Forest Offset Project Planning

    OpenAIRE

    Smith, James E.; Coeli M. Hoover

    2012-01-01

    The documented role of United States forests in sequestering carbon, the relatively low cost of forest-based mitigation, and the many co-benefits of increasing forest carbon stocks all contribute to the ongoing trend in the establishment of forest-based carbon offset projects. We present a broad analysis of forest inventory data using site quality indicators to provide guidance to managers planning land acquisition for forest-based greenhouse gas mitigation projects. Specifically, we summariz...

  3. Soil organic carbon stocks in estuarine and marine mangrove ecosystems are driven by nutrient colimitation of P and N.

    Science.gov (United States)

    Weiss, Christian; Weiss, Joanna; Boy, Jens; Iskandar, Issi; Mikutta, Robert; Guggenberger, Georg

    2016-07-01

    Mangroves play an important role in carbon sequestration, but soil organic carbon (SOC) stocks differ between marine and estuarine mangroves, suggesting differing processes and drivers of SOC accumulation. Here, we compared undegraded and degraded marine and estuarine mangroves in a regional approach across the Indonesian archipelago for their SOC stocks and evaluated possible drivers imposed by nutrient limitations along the land-to-sea gradients. SOC stocks in natural marine mangroves (271-572 Mg ha(-1) m(-1)) were much higher than under estuarine mangroves (100-315 Mg ha(-1) m(-1)) with a further decrease caused by degradation to 80-132 Mg ha(-1) m(-1). Soils differed in C/N ratio (marine: 29-64; estuarine: 9-28), δ (15)N (marine: -0.6 to 0.7‰; estuarine: 2.5 to 7.2‰), and plant-available P (marine: 2.3-6.3 mg kg(-1); estuarine: 0.16-1.8 mg kg(-1)). We found N and P supply of sea-oriented mangroves primarily met by dominating symbiotic N2 fixation from air and P import from sea, while mangroves on the landward gradient increasingly covered their demand in N and P from allochthonous sources and SOM recycling. Pioneer plants favored by degradation further increased nutrient recycling from soil resulting in smaller SOC stocks in the topsoil. These processes explained the differences in SOC stocks along the land-to-sea gradient in each mangrove type as well as the SOC stock differences observed between estuarine and marine mangrove ecosystems. This first large-scale evaluation of drivers of SOC stocks under mangroves thus suggests a continuum in mangrove functioning across scales and ecotypes and additionally provides viable proxies for carbon stock estimations in PES or REDD schemes. PMID:27547332

  4. How do soil organic carbon stocks change after cropland abandonment in Mediterranean humid mountain areas?

    Science.gov (United States)

    Nadal-Romero, E; Cammeraat, E; Pérez-Cardiel, E; Lasanta, T

    2016-10-01

    The effects of land use changes on soil carbon stocks are a matter of concern stated in international policy agendas on the mitigation of greenhouse emissions. Afforestation is increasingly viewed as an environmental restorative land use change prescription and is considered one of the most efficient carbon sequestration strategies currently available. Given the large quantity of CO2 that soils release annually, it is important to understand disturbances in vegetation and soil resulting from land use changes. The main objective of this study is to assess the effects of land abandonment, land use change and afforestation practices on soil organic carbon (SOC) dynamics. For this aim, five different land covers (bare soil, permanent pastureland, secondary succession, Pinus sylvestris (PS) and Pinus nigra (PN) afforestation), in the Central Spanish Pyrenees, were analysed. SOC dynamics have been studied in the bulk soil, and in the fractions separated according to two methodologies: (i) aggregate size distribution, and (ii) density fractionation, and rates of carbon mineralization have been determined by measuring CO2 evolution using an automated respirometer. The results showed that: (i) SOC contents were higher in the PN sites in the topsoil (10cm), (ii) when all the profiles were considered no significant differences were observed between pastureland and PN, (iii) SOC accumulation under secondary succession is a slow process, and (iv) pastureland should also be considered due to the relative importance in SOC stocks. The first step of SOC stabilization after afforestation is the formation of macro-aggregates promoted by large inputs of SOC, with a high contribution of labile organic matter. However, our respiration experiments did not show evidence of SOC stabilization. SOC mineralization was higher in the top layers and values decreased with depth. These results gain insights into which type of land management is most appropriate after land abandonment for SOC

  5. Impact of 40 years poplar cultivation on soil carbon stocks and greenhouse gas fluxes

    Directory of Open Access Journals (Sweden)

    C. Ferré

    2005-08-01

    Full Text Available Within the JRC Kyoto Experiment in the Regional Park and UN-Biosphere Reserve "Parco Ticino" (North-Italy, near Pavia, the soil carbon stocks and fluxes of CO2, N2O, and CH4 were measured in a poplar plantation in comparison with a natural mesohygrophilous deciduous forest nearby, which represents the pristine land cover of the area. Soil fluxes were measured using the static and dynamic closed chamber techniques for CH4 N2O, and CO2, respectively. We made further a pedological study to relate the spatial variability found with soil parameters.

    Annual emission fluxes of N2O and CO2 and deposition fluxes of CH4 were calculated for the year 2003 for the poplar plantation and compared to those measured at the natural forest site. N2O emissions at the poplar plantation were 0.15$plusmn;0.1 g N2O m-2 y-1 and the difference to the emissions at the natural forest of 0.07±0.06 g N2O m-2 y-1 are partly due to a period of high emissions after the flooding of the site at the end of 2002. CH4 consumption at the natural forest was twice as large as at the poplar plantation. In comparison to the relict forest, carbon stocks in the soil under the poplar plantation were depleted by 61% of surface (10 cm carbon and by 25% down the profile under tillage (45 cm. Soil respiration rates were not significant different at both sites with 1608±1053 and 2200±791 g CO2 m-2 y-1 at the poplar plantation and natural forest, respectively, indicating that soil organic carbon is much more stable in the natural forest. In terms of the greenhouse gas budget, the non-CO2 gases contributed minor to the overall soil balance with only 0.9% (N2O and -0.3% (CH4 of CO2-eq emissions in the

  6. Mapping soil organic carbon stocks by robust geostatistical and boosted regression models

    Science.gov (United States)

    Nussbaum, Madlene; Papritz, Andreas; Baltensweiler, Andri; Walthert, Lorenz

    2013-04-01

    Carbon (C) sequestration in forests offsets greenhouse gas emissions. Therefore, quantifying C stocks and fluxes in forest ecosystems is of interest for greenhouse gas reporting according to the Kyoto protocol. In Switzerland, the National Forest Inventory offers comprehensive data to quantify the aboveground forest biomass and its change in time. Estimating stocks of soil organic C (SOC) in forests is more difficult because the variables needed to quantify stocks vary strongly in space and precise quantification of some of them is very costly. Based on data from 1'033 plots we modeled SOC stocks of the organic layer and the mineral soil to depths of 30 cm and 100 cm for the Swiss forested area. For the statistical modeling a broad range of covariates were available: Climate data (e. g. precipitation, temperature), two elevation models (resolutions 25 and 2 m) with respective terrain attributes and spectral reflectance data representing vegetation. Furthermore, the main mapping units of an overview soil map and a coarse scale geological map were used to coarsely represent the parent material of the soils. The selection of important covariates for SOC stocks modeling out of a large set was a major challenge for the statistical modeling. We used two approaches to deal with this problem: 1) A robust restricted maximum likelihood method to fit linear regression model with spatially correlated errors. The large number of covariates was first reduced by LASSO (Least Absolute Shrinkage and Selection Operator) and then further narrowed down to a parsimonious set of important covariates by cross-validation of the robustly fitted model. To account for nonlinear dependencies of the response on the covariates interaction terms of the latter were included in model if this improved the fit. 2) A boosted structured regression model with componentwise linear least squares or componentwise smoothing splines as base procedures. The selection of important covariates was done by the

  7. Biomass Accumulation and Carbon Stocks in 13 Different Clones of Teak (Tectona Grandis Linn. F.) in Odisha, India

    OpenAIRE

    Manoj Kumar Behera; Nilima Priyadarshini Mohapatra

    2015-01-01

    The rate of biomass accumulation and carbon stocks of 13 different clones of Teak in Odisha were studied to identify the promising genotypes suitable for massive clonal plantations in Odisha. ORANP2 produced highest biomass among the 13 clones of teak i.e. 223.72m3/ha, while ORANP1 registered lowest value of 64.05m3/ha in regards to biomass accumulation. The total carbon stock values were found in the range of 32.02-111.86t/ha for 13 different clones of teak. The Mean Annual Increment (MAI) v...

  8. Underestimation of soil carbon stocks by Yasso07, Q, and CENTURY models in boreal forest linked to overlooking site fertility

    Science.gov (United States)

    Ťupek, Boris; Ortiz, Carina; Hashimoto, Shoji; Stendahl, Johan; Dahlgren, Jonas; Karltun, Erik; Lehtonen, Aleksi

    2016-04-01

    The soil organic carbon stock (SOC) changes estimated by the most process based soil carbon models (e.g. Yasso07, Q and CENTURY), needed for reporting of changes in soil carbon amounts for the United Nations Framework Convention on Climate Change (UNFCCC) and for mitigation of anthropogenic CO2 emissions by soil carbon management, can be biased if in a large mosaic of environments the models are missing a key factor driving SOC sequestration. To our knowledge soil nutrient status as a missing driver of these models was not tested in previous studies. Although, it's known that models fail to reconstruct the spatial variation and that soil nutrient status drives the ecosystem carbon use efficiency and soil carbon sequestration. We evaluated SOC stock estimates of Yasso07, Q and CENTURY process based models against the field data from Swedish Forest Soil National Inventories (3230 samples) organized by recursive partitioning method (RPART) into distinct soil groups with underlying SOC stock development linked to physicochemical conditions. These models worked for most soils with approximately average SOC stocks, but could not reproduce higher measured SOC stocks in our application. The Yasso07 and Q models that used only climate and litterfall input data and ignored soil properties generally agreed with two third of measurements. However, in comparison with measurements grouped according to the gradient of soil nutrient status we found that the models underestimated for the Swedish boreal forest soils with higher site fertility. Accounting for soil texture (clay, silt, and sand content) and structure (bulk density) in CENTURY model showed no improvement on carbon stock estimates, as CENTURY deviated in similar manner. We highlighted the mechanisms why models deviate from the measurements and the ways of considering soil nutrient status in further model development. Our analysis suggested that the models indeed lack other predominat drivers of SOC stabilization

  9. The influence of financial ratios on different sectors : A Multivariate Regression of OMXS stocks to determine what financial ratios influence stock growth in different sectors most

    OpenAIRE

    Ma, San-San; TRUONG, Patrick

    2015-01-01

    Financial ratios are used to indicate a stocks performance. This thesis aims to clarify if there are any differences in how sectors respond to financial ratios. By doing an deductive research this thesis establishes that the most prominent financial ratios are different in the various sectors while also establishing that financial ratios account only for a small part of the stock growth. The thesis also contains a qualitative study which attempts to discuss the forces behind stock growth. The...

  10. The interaction between biogeophysical and biogeochemical processes and their feedback on permafrost soil carbon stocks

    Science.gov (United States)

    ElMasri, B.; Barman, R.; Jain, A. K.

    2013-12-01

    , instead we emphasis on the importance of biogeophysical and biophysical processes and feedbacks between them in modeling permafrost carbon stocks.

  11. Global assessment of soil organic carbon stocks and spatial distribution of histosols: the Machine Learning approach

    Science.gov (United States)

    Hengl, Tomislav

    2016-04-01

    Preliminary results of predicting distribution of soil organic soils (Histosols) and soil organic carbon stock (in tonnes per ha) using global compilations of soil profiles (about 150,000 points) and covariates at 250 m spatial resolution (about 150 covariates; mainly MODIS seasonal land products, SRTM DEM derivatives, climatic images, lithological and land cover and landform maps) are presented. We focus on using a data-driven approach i.e. Machine Learning techniques that often require no knowledge about the distribution of the target variable or knowledge about the possible relationships. Other advantages of using machine learning are (DOI: 10.1371/journal.pone.0125814): All rules required to produce outputs are formalized. The whole procedure is documented (the statistical model and associated computer script), enabling reproducible research. Predicted surfaces can make use of various information sources and can be optimized relative to all available quantitative point and covariate data. There is more flexibility in terms of the spatial extent, resolution and support of requested maps. Automated mapping is also more cost-effective: once the system is operational, maintenance and production of updates are an order of magnitude faster and cheaper. Consequently, prediction maps can be updated and improved at shorter and shorter time intervals. Some disadvantages of automated soil mapping based on Machine Learning are: Models are data-driven and any serious blunders or artifacts in the input data can propagate to order-of-magnitude larger errors than in the case of expert-based systems. Fitting machine learning models is at the order of magnitude computationally more demanding. Computing effort can be even tens of thousands higher than if e.g. linear geostatistics is used. Many machine learning models are fairly complex often abstract and any interpretation of such models is not trivial and require special multidimensional / multivariable plotting and data mining

  12. Estimating national forest carbon stocks and dynamics: combining models and remotely sensed information

    Science.gov (United States)

    Smallman, Luke; Williams, Mathew

    2016-04-01

    Forests are a critical component of the global carbon cycle, storing significant amounts of carbon, split between living biomass and dead organic matter. The carbon budget of forests is the most uncertain component of the global carbon cycle - it is currently impossible to quantify accurately the carbon source/sink strength of forest biomes due to their heterogeneity and complex dynamics. It has been a major challenge to generate robust carbon budgets across landscapes due to data scarcity. Models have been used but outputs have lacked an assessment of uncertainty, making a robust assessment of their reliability and accuracy challenging. Here a Metropolis Hastings - Markov Chain Monte Carlo (MH-MCMC) data assimilation framework has been used to combine remotely sensed leaf area index (MODIS), biomass (where available) and deforestation estimates, in addition to forest planting and clear-felling information from the UK's national forest inventory, an estimate of soil carbon from the Harmonized World Database (HWSD) and plant trait information with a process model (DALEC) to produce a constrained analysis with a robust estimate of uncertainty of the UK forestry carbon budget between 2000 and 2010. Our analysis estimates the mean annual UK forest carbon sink at -3.9 MgC ha‑1yr‑1 with a 95 % confidence interval between -4.0 and -3.1 MgC ha‑1 yr‑1. The UK national forest inventory (NFI) estimates the mean UK forest carbon sink to be between -1.4 and -5.5 MgC ha‑1 yr‑1. The analysis estimate for total forest biomass stock in 2010 is estimated at 229 (177/232) TgC, while the NFI an estimated total forest biomass carbon stock of 216 TgC. Leaf carbon area (LCA) is a key plant trait which we are able to estimate using our analysis. Comparison of median estimates for LCA retrieved from the analysis and a UK land cover map show higher and lower values for LCA are estimated areas dominated by needle leaf and broad leaf forests forest respectively, consistent with

  13. Ecological Variability and Carbon Stock Estimates of Mangrove Ecosystems in Northwestern Madagascar

    Directory of Open Access Journals (Sweden)

    Trevor G. Jones

    2014-01-01

    Full Text Available Mangroves are found throughout the tropics, providing critical ecosystem goods and services to coastal communities and supporting rich biodiversity. Despite their value, world-wide, mangroves are being rapidly degraded and deforested. Madagascar contains approximately 2% of the world’s mangroves, >20% of which has been deforested since 1990 from increased extraction for charcoal and timber and conversion to small to large-scale agriculture and aquaculture. Loss is particularly prominent in the northwestern Ambaro and Ambanja bays. Here, we focus on Ambaro and Ambanja bays, presenting dynamics calculated using United States Geological Survey (USGS national-level mangrove maps and the first localized satellite imagery derived map of dominant land-cover types. The analysis of USGS data indicated a loss of 7659 ha (23.7% and a gain of 995 ha (3.1% from 1990–2010. Contemporary mapping results were 93.4% accurate overall (Kappa 0.9, with producer’s and user’s accuracies ≥85%. Classification results allowed partitioning mangroves in to ecologically meaningful, spectrally distinct strata, wherein field measurements facilitated estimating the first total carbon stocks for mangroves in Madagascar. Estimates suggest that higher stature closed-canopy mangroves have average total vegetation carbon values of 146.8 Mg/ha (±10.2 and soil organic carbon of 446.2 (±36.9, supporting a growing body of studies that mangroves are amongst the most carbon-dense tropical forests.

  14. Past and Prospective Carbon Stocks of United States Forests: Implications for Research Priorities and Mitigation Policies

    Science.gov (United States)

    Birdsey, R.; Pan, Y.; McGuire, A. D.; Zhang, F.; Chen, J. M.

    2014-12-01

    United States forests and wood products have been a significant and persistent carbon sink of 100-200 million tons annually since 1950, currently offsetting about 12% of U.S. emissions of CO2. This carbon sink is caused by recovery of forest C stocks following timber harvest and abandonment of agricultural land over the last 150 years, and more recently the growth-enhancing effects of N deposition, increasing atmospheric CO2, and climate variability. The forest carbon sink would have been significantly larger if not for continued losses of forest to other land uses such as urban development, and increasing impacts from natural disturbances such as fire and insect outbreaks. Projections of the future U.S. C sink have raised concerns that it may disappear in a few decades because of slower growth, continued losses of forest area, and increasing demand for timber products especially bioenergy. However, continuing atmospheric and climate changes may delay this projected decline in the sink strength for another 50 years or longer. Research is urgently needed to improve projections of land-use changes and demand for timber, quantify the large-scale effects of atmospheric change and climate variability, and develop modeling approaches that can effectively integrate these multiple factors. Policy decisions to meet emissions reduction targets are partially dependent on assumptions about the magnitude of the future forest carbon sink; therefore, it is important to have convincing projections about how these various driving factors will affect forests in the future.

  15. Disclosure, Conservatism and their Influence on Cost of Capital of the Companies Accepted by Tehran Stock Exchange (TSE)

    OpenAIRE

    Zare, R.; Heidari, Z; Salehi, M.; H. Jourkesh

    2013-01-01

    This study attempts to examine the relevance of Disclosure, conservatism and their influence on cost of capital of the companies accepted by Tehran Stock Exchange (TSE) and Compare the relative information content of them. Based on sampling, 113 firms from Tehran Stock Exchange (TSE) were selected and examined during 2003 to 2009. The results support the priority of accounting figures over dividend policy. The results show there is some significant relation between the conservatism rate and c...

  16. The carbon cycle in Mexico: past, present and future of C stocks and fluxes

    Directory of Open Access Journals (Sweden)

    G. Murray-Tortarolo

    2015-08-01

    Full Text Available We modelled the carbon (C cycle in Mexico with a process-based approach. We used different available products (satellite data, field measurements, models and flux towers to estimate C stocks and fluxes in the country at three different time frames: present (defined as the period 2000–2005, the past century (1901–2000 and the remainder of this century (2010–2100. Our estimate of the gross primary productivity (GPP for the country was 2137 ± 1023 Tg C yr−1 and a total C stock of 34 506 ± 7483 Tg C, with 20 347 ± 4622 Pg C in vegetation and 14 159 ± 3861 in the soil. Contrary to other current estimates for recent decades, our results showed that Mexico was a C sink over the period 1990–2009 (+31 Tg C yr−1 and that C accumulation over the last century amounted to 1210 ± 1040 Tg C. We attributed this sink to the CO2 fertilization effect on GPP, which led to an increase of 3408 ± 1060 Tg C, while both climate and land use reduced the country C stocks by −458 ± 1001 and −1740 ± 878 Tg C, respectively. Under different future scenarios the C sink will likely continue over 21st century, with decreasing C uptake as the climate forcing becomes more extreme. Our work provides valuable insights on relevant driving processes of the C-cycle such as the role of drought in marginal lands (e.g. grasslands and shrublands and the impact of climate change on the mean residence time of C in tropical ecosystems.

  17. The carbon cycle in Mexico: past, present and future of C stocks and fluxes

    Science.gov (United States)

    Murray-Tortarolo, G.; Friedlingstein, P.; Sitch, S.; Jaramillo, V. J.; Murguía-Flores, F.; Anav, A.; Liu, Y.; Arneth, A.; Arvanitis, A.; Harper, A.; Jain, A.; Kato, E.; Koven, C.; Poulter, B.; Stocker, B. D.; Wiltshire, A.; Zaehle, S.; Zeng, N.

    2016-01-01

    We modeled the carbon (C) cycle in Mexico with a process-based approach. We used different available products (satellite data, field measurements, models and flux towers) to estimate C stocks and fluxes in the country at three different time frames: present (defined as the period 2000-2005), the past century (1901-2000) and the remainder of this century (2010-2100). Our estimate of the gross primary productivity (GPP) for the country was 2137 ± 1023 TgC yr-1 and a total C stock of 34 506 ± 7483 TgC, with 20 347 ± 4622 TgC in vegetation and 14 159 ± 3861 in the soil.Contrary to other current estimates for recent decades, our results showed that Mexico was a C sink over the period 1990-2009 (+31 TgC yr-1) and that C accumulation over the last century amounted to 1210 ± 1040 TgC. We attributed this sink to the CO2 fertilization effect on GPP, which led to an increase of 3408 ± 1060 TgC, while both climate and land use reduced the country C stocks by -458 ± 1001 and -1740 ± 878 TgC, respectively. Under different future scenarios, the C sink will likely continue over the 21st century, with decreasing C uptake as the climate forcing becomes more extreme. Our work provides valuable insights on relevant driving processes of the C cycle such as the role of drought in drylands (e.g., grasslands and shrublands) and the impact of climate change on the mean residence time of soil C in tropical ecosystems.

  18. Towards integrating the influence of erosion on within field variability of C input, stock and stability in regional SOC estimates

    Science.gov (United States)

    Meersmans, J.; Quine, T. A.

    2013-12-01

    Improved management of the SOC pool has become an important issue for policymakers in order to maintain soil quality and reduce climate change. Hence, there exists an increased interest in accurate mapping of SOC at the regional scale. Most of these studies are limited to topsoil, consider only factors present at the landscape scale (e.g. climate, land use, soil type) and are at rather coarse resolution. Consequently, the variability of SOC at smaller scales in complex terrain driven by soil erosion, such as stable subsoil carbon buried in depositional areas, is still rather understudied and is not (well) presented in these estimates. Nevertheless, incorporating this smaller level of spatial detail will most probably have a major influence on regional SOC stock dynamics' calculations and mapping. In the present study we aim to unravel the variation in quantity and quality of SOC depth distributions along typical hillslope transects under cropland (Devon, UK) and relate these to soil redistribution rates and variations in C input, i.e. below and above ground biomass productivity. The radionuclide isotope Caesium-137 (137Cs) was used as proxy for erosion. The results show contrasting vertical patterns in SOC stock and stability depending on the rate and type of erosion. For example, sites characterized by deposition due to water erosion (i.e. foot slope) have much higher SOC values near the surface, but show a fast decline with depth, while sites characterized by deposition due to tillage erosion (i.e. most concave position) have moderated SOC surface values that stay constant until a depth of 50 cm, but with increasing stability with depth. The above ground biomass productivity is most linked to water erosion, since we found lowest above ground biomass at the steepest slope position and the highest above ground biomass at the foot slopes. Furthermore, root biomass in the most concave section is significantly higher as compared to any other topo-position. The present

  19. CARBON STOCK DETERMINATION IN TEAK (Tectona grandis L. f. AT DIFFERENT AGES

    Directory of Open Access Journals (Sweden)

    Eleusa Maria Almeida

    2010-12-01

    Full Text Available The objective of this study was to evaluate the quantity of carbon in teak (Tectona grandis L.f., with 0.5; 1.5; 2.5; 3.5 and 5.5 years of age, during one year. The teak evaluated belonged to the BRASTECA AGROFLORESTAL LTDA company, located in the municipality of Santo Antônio of Leverger, Mato Grosso, Brazil. The carbon stock for each age was assessed every 90 days by determining the amount of litter dry mass, organic carbon proportion in the soil, root density in the soil and the volume of the staff and crown in the three teak trees randomly selected for harvest. The assessment of the plant size, as height, diameter at chest height and crown projection, was carried out with twenty preserved plants at each age. The dry mass of the roots was determined from the relation between the soil volume and the density of roots of the three plants per age, by making four perforations per plant, with six samples for each, up to 0.90 m of depth. The carbon proportion in the soil and in the litter was obtained by age at each collection through laboratory analysis. The average carbon found per hectare was 122.5 t of C at 0.5 years; 104.3 t of C at 1.5 years; 180.8 t of C at 2.5 years; 303.1 t of C at 3.5 years and 322.3 t of C at 5.5 years, considering the numbers of plants per hectare at the different ages. Afterward, the average distribution of carbon per system component was found to be 90.8% in the soil, 5.04% to the aerial part, 3.04% in the roots and 1.21% in the litter.

  20. The impact of land afforestation on carbon stocks surrounding Tehran, Iran

    Institute of Scientific and Technical Information of China (English)

    Saeid Varamesh; Seyyed Mohsen Hosseini; Farshad Keivan Behjou; Ebrahim Fataei

    2014-01-01

    The city of Tehran, like many polluted metropolises of the world, has higher emissions of greenhouse gases than other cities in Iran, due to heavy consumption of fossil fuel and landuse changes. To estimate carbon sequestration in two 40 year-old stands of plantedCupressus arizonica andFraxinus rotundifolia in degraded lands surrounding Tehran , sampling of above- and below- ground biomass, soil (at two depths of 0-15 and 15-30 cm), and leaf litter was done by systematic random sampling. The total carbon stocks ofC. arizonica and F. rotundifolia stands were respectively 328.20 and 150.69 Mg·ha-1. The aboveground biomass with 233.16(71%) Mg·ha-1 inC. arizonica and 88.16 (58.50%) Mg·ha-1 inF. rotundifolia contributed the most shares to carbon sequestration. The diameter at breast height, total height, basal area, total volume, and biomass ofC. arizonica were significantly (p <0.01) higher than those ofF. rotundifolia. Also the depth of 0-30 cm of soil contributed between 18.29 % and 32.15 % of total ecosystem carbon, respectively. The economic value of carbon sequestration in the two stands in 2011 was calculated at 3.5 and 2.5 million dollars, respectively. Our results indicate that afforestation of the degraded land surrounding Tehran would sequester more carbon than would continuously degraded land, the current status quo. These stands can absorb atmospheric CO2at different rates, thus tree species selection and stand development should be considered in planning future afforestation projects.

  1. Changes in carbon stocks of Danish agricultural mineral soils between 1986 and 2009

    DEFF Research Database (Denmark)

    Taghizadeh-Toosi, Arezoo; Olesen, Jørgen E; Kristensen, Kristian;

    2014-01-01

    To establish a national inventory of soil organic carbon (SOC) stocks and their change over time, soil was sampled in 1986, 1997 and 2009 in a Danish nation-wide 7-km grid and analysed for SOC content. The average SOC stock in 0–100-cm depth soil was 142 t C ha−1, with 63, 41 and 38 t C ha−1 in the...... 0–25, 25–50 and 50–100 cm depths, respectively. Changes at 0–25 cm were small. During 1986–97, SOC in the 25–50-cm layer increased in sandy soils while SOC decreased in loam soils. In the subsequent period (1997–2009), most soils showed significant losses of SOC. From 1986 to 2009, SOC at 0–100 cm...... decreased in loam soils and tended to increase in sandy soils. This trend is ascribed to dairy farms with grass leys being abundant on sandy soils while cereal cropping dominates on loamy soils. A statistical model including soil type, land use and management was applied separately to 0–25, 25–50 and 50...

  2. The microbe-mediated mechanisms affecting topsoil carbon stock in Tibetan grasslands.

    Science.gov (United States)

    Yue, Haowei; Wang, Mengmeng; Wang, Shiping; Gilbert, Jack A; Sun, Xin; Wu, Linwei; Lin, Qiaoyan; Hu, Yigang; Li, Xiangzhen; He, Zhili; Zhou, Jizhong; Yang, Yunfeng

    2015-09-01

    Warming has been shown to cause soil carbon (C) loss in northern grasslands owing to accelerated microbial decomposition that offsets increased grass productivity. Yet, a multi-decadal survey indicated that the surface soil C stock in Tibetan alpine grasslands remained relatively stable. To investigate this inconsistency, we analyzed the feedback responses of soil microbial communities to simulated warming by soil transplant in Tibetan grasslands. Whereas microbial functional diversity decreased in response to warming, microbial community structure did not correlate with changes in temperature. The relative abundance of catabolic genes associated with nitrogen (N) and C cycling decreased with warming, most notably in genes encoding enzymes associated with more recalcitrant C substrates. By contrast, genes associated with C fixation increased in relative abundance. The relative abundance of genes associated with urease, glutamate dehydrogenase and ammonia monoxygenase (ureC, gdh and amoA) were significantly correlated with N2O efflux. These results suggest that unlike arid/semiarid grasslands, Tibetan grasslands maintain negative feedback mechanisms that preserve terrestrial C and N pools. To examine whether these trends were applicable to the whole plateau, we included these measurements in a model and verified that topsoil C stocks remained relatively stable. Thus, by establishing linkages between microbial metabolic potential and soil biogeochemical processes, we conclude that long-term C loss in Tibetan grasslands is ameliorated by a reduction in microbial decomposition of recalcitrant C substrates. PMID:25689025

  3. How do soil properties and soil carbon stocks change after land abandonment in Mediterranean mountain areas?

    Science.gov (United States)

    Nadal Romero, Estela; Cammeraat, Erik; Pérez Cardiel, Estela; Lasanta, Teodoro

    2016-04-01

    Land abandonment and subsequent revegetation processes (due to secondary succession and afforestation practices) are global issues with important implications in Mediterranean mountain areas. Moreover, the effects of land use changes on soil carbon stocks are a matter of concern stated in international policy agendas on the mitigation of greenhouse emissions, and afforestation practices are increasingly viewed as an environmental restorative land use change prescription and are considered one of the most efficient carbon sequestration strategies currently available. The MED-AFFOREST project aims to gain more insight into the discussion by exploring the following central research questions: (i) what is the impact of land abandonment on soil properties? and (ii) how do soil organic carbon change after land abandonment? The main objective of this study is to assess the effects of land abandonment, land use change and afforestation practices on soil properties and soil organic carbon (SOC) dynamics. For this aim, five different land covers (bare soil, meadows, secondary succession, Pinus sylvestris (PS) and Pinus nigra (PN) afforestation), in the Central Spanish Pyrenees were analysed. Results showed that changes in soil properties after land abandonment were limited, even if afforestation practices were carried out and no differences were observed between natural succession and afforestation. The results on SOC dynamics showed that: (i) SOC contents were higher in the PN sites in the topsoil (10 cm), (ii) when all the profile was considered no significant differences were observed between meadows and PN, (iii) SOC accumulation under secondary succession is a slow process, and (iv) meadows should also be considered due to the relative importance in SOC stocks. The first step of SOC stabilization after afforestation is the formation of macro-aggregates promoted by large inputs of SOC, with a high contribution of labile organic matter. However, our respiration

  4. Forest Biomass, Carbon Stocks, and Macrofungal Dynamics: A Case Study in Costa Rica

    Directory of Open Access Journals (Sweden)

    Carlos Rojas

    2014-01-01

    Full Text Available There are few published studies providing information about macrofungal biology in a context of forest dynamics in tropical areas. For this study, a characterization of above-ground standing tree biomass and carbon stocks was performed for four different forest subtypes within two life zones in Costa Rica. Fungal productivity and reproductive success were estimated and analyzed in the context of the forest systems studied and results showed fungal dynamics to be a complex and challenging topic. In the present study, fungal productivity was higher in forest patches with more tree density but independent from life zones, whereas fungal biomass was higher in premontane areas with ectomycorrhizal dominant trees. Even though some observed patterns could be explained in terms of climatic differences and biotic relationships, the high fungal productivity observed in dry forests was an interesting finding and represents a topic for further studies.

  5. Soil Carbon Stocks in a Shifting Ecosystem; Climate Induced Migration of Mangroves into Salt Marsh

    Science.gov (United States)

    Simpson, L.; Osborne, T.; Feller, I. C.

    2015-12-01

    Across the globe, coastal wetland vegetation distributions are changing in response to climate change. The increase in global average surface temperature has already caused shifts in the structure and distribution of many ecological communities. In parts of the southeastern United States, increased winter temperatures have resulted in the poleward range expansion of mangroves at the expense of salt marsh habitat. Our work aims to document carbon storage in the salt marsh - mangrove ecotone and any potential changes in this reservoir that may ensue due to the shifting range of this habitat. Differences in SOM and C stocks along a latitudinal gradient on the east coast of Florida will be presented. The gradient studied spans 342 km and includes pure mangrove habitat, the salt marsh - mangrove ecotone, and pure salt marsh habitat.This latitudinal gradient gives us an exceptional opportunity to document and investigate ecosystem soil C modifications as mangroves transgress into salt marsh habitat due to climatic change.

  6. Factors influencing the alignment of accounting information systems of accepted manufacturing firms in Tehran Stock Exchange

    Directory of Open Access Journals (Sweden)

    Fazel Tamoradi

    2014-03-01

    Full Text Available The primary objective of this paper is to detect factors influencing the alignment of accounting information systems for firms in manufacturing sector listed on Tehran Stock Exchange. The concept of alignment has been investigated for many years, and strategic alignment plays essential role in increasing company performance. This paper investigates different levels of alignment and studies the factors, which influence alignment. More specifically, the work concentrates on the alignment between the requirements for accounting information (AIS requirements and the capacity of accounting systems (AIS capacity to build the information, in the specific context of manufacturing in Iran. The research sample consists of 216 companies over the period 2011-2007. The fit between these two sets was explored based on the moderation method and evidences indicate that AIS alignment in some firms was high. In addition, the relationship between the dependent variable and independent variables through multiple regressions yields a positive relationship between these variables.

  7. Simulating Soil Organic Carbon Stock Changes in Agro-ecosystems using CQESTR, DayCent, and IPCC Tier 1 Methods

    Science.gov (United States)

    Models are often used to quantify how land use change and management impact soil organic carbon (SOC) stocks because it is often not feasible to use direct measuring methods. Because models are simplifications of reality, it is essential to compare model outputs with measured values to evaluate mode...

  8. Impact of tree species on soil carbon stocks and soil acidity in southern Sweden

    International Nuclear Information System (INIS)

    The impact of tree species on soil carbon stocks and acidity in southern Sweden was studied in a non-replicated plantation with monocultures of 67-year-old ash (Fraxinus excelsior L.), beech (Fagus silvatica L.), elm (Ulmus glabra Huds.), hornbeam (Carpinusbetulus L.), Norway spruce (Picea abies L.) and oak (Quercus robur L.). The site was characterized by a cambisol on glacial till. Volume-determined soil samples were taken from the O-horizon and mineral soil layers to 20 cm. Soil organic carbon (SOC), total nitrogen (TN), pH (H2O), cation-exchange capacity and base saturation at pH 7 and exchangeable calcium, magnesium, potassium and sodium ions were analysed in the soil fraction hornbeam > oak > beech > ash > elm. The pH in the O-horizon ranged in the order elm > ash > hornbeam > beech > oak > spruce. In the mineral soil, SOC and TN ranged in the order elm > oak > ash = hornbeam > spruce > beech, i.e. partly reversed, and pH ranged in the same order as for the O-horizon. It is suggested that spruce is the best option for fertile sites in southern Sweden if the aim is a high carbon sequestration rate, whereas elm, ash and hornbeam are the best solutions if the aim is a low soil acidification rate

  9. Stock, turnover and functions of carbon in heavily weathered soils under lowland rainforest transformation systems

    Science.gov (United States)

    Guillaume, Thomas; Kuzyakov, Yakov

    2013-04-01

    Tropical rainforest are experiencing worldwide a strong lost through deforestation and transformation into agricultural systems. Land use changes in such ecosystems leads to major modifications of soils properties and processes. One indication of it are the losses of organic carbon content (Corg); an important soil fertility parameter in heavily weathered soil. Between 1985 and 2007, Sumatra (Indonesia) has lost half of his remaining natural rainforest, which currently covers only 30% the island. The deforestation is still ongoing and the main drivers of deforestation are oil palm, rubber and timber industries. Our study aims to identify and quantify the impacts of lowland rainforest transformation systems (TS): oil palm, rubber and jungle rubber plantations on soil organic carbon (SOC) and nitrogen (SON) quality, turnover and stocks and so, on soil fertility and functions. We hypothesize that transformation of natural lowland rainforest changes not only C stock and budget throughout quantity and quality of C input, but also DOM production and water consumption by vegetation, leading to a relocation of C in the subsoil. This should be reflected in C and N content in soil profile horizons as well as their δ13C and δ15N isotopic signatures. We will evaluate also C stability through biological, thermal and chemical stability in bulk soil and aggregate fractions. The TS investigated, including lowland rainforest as reference sites, are located in Jambi Province (Sumatra). Soil has been described and sampled per horizon on 4 replicates of each TS in 2 different regions (32 sites) in Autumn 2012. As hypothesized, first results show strong effects of forest transformation on C and N content, as well as on isotopic signatures of soil. Those results will also be used further to select DOM sampling depths and adequate horizons to perform sorption and incubation experiments.

  10. The effect of cassava-based bioethanol production on above-ground carbon stocks: A case study from Southern Mali

    International Nuclear Information System (INIS)

    Increasing energy use and the need to mitigate climate change make production of liquid biofuels a high priority. Farmers respond worldwide to this increasing demand by converting forests and grassland into biofuel crops, but whether biofuels offer carbon savings depends on the carbon emissions that occur when land use is changed to biofuel crops. This paper reports the results of a study on cassava-based bioethanol production undertaken in the Sikasso region in Southern Mali. The paper outlines the estimated impacts on above-ground carbon stocks when land use is changed to increase cassava production. The results show that expansion of cassava production for bioethanol will most likely lead to the conversion of fallow areas to cassava. A land use change from fallow to cassava creates a reduction in the above-ground carbon stocks in the order of 4–13 Mg C ha−1, depending on (a) the age of the fallow, (b) the allometric equation used and (c) whether all trees are removed or the larger, useful trees are preserved. This ‘carbon debt’ associated with the above-ground biomass loss would take 8–25 years to repay if fossil fuels are replaced with cassava-based bioethanol. - Highlights: ► Demands for biofuels make production of cassava-based bioethanol a priority. ► Farmers in Southern Mali are likely to convert fallow areas to cassava production. ► Converting fallow to cassava creates reductions in above-ground carbon stocks. ► Estimates of carbon stock reductions include that farmers preserve useful trees. ► The carbon debt associated with above-ground biomass loss takes 8–25 years to repay.

  11. The inventory of the carbon stocks in sub tropical forests of Pakistan for reporting under Kyoto Protocol

    Institute of Scientific and Technical Information of China (English)

    Syed Moazzam Nizami

    2012-01-01

    The United Nations Framework Convention on Climate Change (UNFCCC) requires reporting net carbon stock changes and anthropogenic greenhouse gas emissions,including those related to forests.This paper describes the status of carbon stocks in sub tropical forests of Pakistan.There are two major sub types in subtropical forests of Pakistan viz a viz Subtropical Chir Pine and Subtropical broadleaved forests.A network of sample plots was laid out in four selected site.Two sites were selected from sub tropical Chit Pine (Pinus roxburghii) forests and two from Subtropical broadleaved forests.Measurement and data acquisition protocols were developed specifically for the inventory carried out from 2005 to 2010.In total 261 plots (each of lha.) were established.Estimation of diameter,basal area,height,volume and biomass was carried out to estimate carbon stocks in each of the four carbon pools of above- and below-ground live biomass.Soil carbon stocks were also determined by doing soil sampling.In mature (~100 years old) pine forest stand at Ghoragali and Lehterar sites,a mean basal area of 30.38and 26.11 m2·ha-1 represented mean volume of 243 and 197 m3·ha-1,respectively.The average biomass (t·ha-1) was 237 in Ghoragali site and 186 t.ha-1in Lehterar site,which is equal to 128 and 100 t C ha-1 including soil C.However,on average basis both the forests have 114.5± 2.26 t·ha-1 of carbon stock which comprises of 92% in tree biomass and only 8% in the top soils.In mixed broadleaved evergreen forests a mean basal area (m2·ha-1) was 3.06 at Kherimurat with stem volume of 12.86 and 2.65 at Sohawa with stem volume of 1 1.40 m3·ha-1.The average upper and under storey biomass (t·ha-1) was 50.93 in Kherimurat site and 40.43 t·ha-1in Sohawa site,which is equal to 31.18 and 24.36 t C ha-1 including soil C stocks.This study provides a protocol and valuable baseline data for monitoring biomass and carbon stocks in Pakistan's managed and unmanaged sub-tropical forests.

  12. Ten Year Evaluation of Carbon Stock in Mangrove Plantation Reforested from an Abandoned Shrimp Pond

    Directory of Open Access Journals (Sweden)

    Jirasak Chukwamdee

    2012-06-01

    Full Text Available Forest carbon stocks—both in terms of the standing biomass and the soil organic carbon (OC—were monitored in the mangrove plantation reforested from an abandoned shrimp pond for the 10 years following land excavation. Excavation to a level of 25 cm below the existing ground level increased the inundation time of tidal water from 463 to 7,597 hours per year, resulting in a significant increase of survival/growth rates for planted mangrove species, Rhizophora mucronata (RM and Bruguiera cylindrica (BC, and of carbon stocks as well. RM showed high rates of standing biomass accumulation with 98.7 ton/ha while 28.8 ton/ha for BC was measured over 10 years in the excavated area. In contrast, the unexcavated area showed low rates of biomass accumulation, 1.04 ton/ha for RM and 0.53 ton/ha for BC in the same period. The excavated area recorded a twofold increase of soil OC in the upper 5 cm of the surface soil from 71.8 to 154.8 ton/ha in 10 years, however it decreased to 68.3 ton/ha in the unexcavated area where soil OC is susceptible to decomposition. These results imply that the potential of carbon sinks in reforested land from abandoned areas cannot be developed unless hydraulic conditions are properly recovered. The fast growing species Avicennia marina (AM grew quickly for the first two years after colonization but its growth slowed down afterwards, showing a limited ability of carbon capture.

  13. Plant growth controls short-term changes in soil organic carbon (SOC) stocks of croplands - new insights from the CarboZALF experiment

    Science.gov (United States)

    Hoffmann, Mathias; Jurisch, Nicole; Garcia Alba, Joana; Albiac Borraz, Elisa; Schmidt, Marten; Verch, Gernot; Sommer, Michael; Augustin, Jürgen

    2016-04-01

    The long-term influence of crop rotations, climate conditions or soil type on soil organic carbon stock (SOC) patterns and gaseous C emissions of agricultural landscapes is widely recognized. However, the question of short-term seasonal changes in SOC within these areas remains unclear. A main reason for this is the detection problem of temporal and spatial variability in gaseous C exchange and thus, changes in SOC stocks (ΔSOC) in a high resolution. This study introduces dynamic C balances as a method to obtain seasonal changes in SOC stocks. Dynamic C balances were calculated by a combination of automatic chamber CO2 exchange measurements and empirical biomass models. Measurements were performed for three consecutive years at a colluvial depression (Colluvic Regosol) in the hummocky ground moraine landscape of NE Germany (CarboZALF experimental site). The investigated crop rotation was maize, winter fodder rye, maize, winter fodder rye, and sudangrass. The site is characterized by a gradient in ground water level (GWL) and related spatial heterogeneity in soil properties, such as SOC as well as soil nitrogen (Nt) stocks. Modelled dynamic C balances reveal that up to 79% of the standard deviation of estimated annual ΔSOC between single chambers emerged during the main period of crop growth (three months in summer). No significant changes in ΔSOC were detected outside the growing season. Instead, differences between chambers remain constant despite ΔSOC dynamics. Environmental variables (Nt stocks of Ap horizon and GWL), affecting plant-mediated C sequestration, explained up to 95% of temporal and spatial variability in CO2 exchange and ΔSOC. Thus, plant activities were the major catalyst for small scale differences in annual ΔSOC of croplands.

  14. The Impact of Afforestation on the Carbon Stocks of Mineral Soils Across the Republic of Ireland.

    Science.gov (United States)

    Wellock, M.; Laperle, C.; Kiely, G.; Reidy, B.; Duffy, C.; Tobin, B.

    2009-04-01

    At the beginning of the twentieth century forests accounted for only 1% of the total Irish land cover (Pilcher & Mac an tSaoir, 1995). However, due to the efforts of successive governments there has been rapid afforestation since the 1960s resulting in a 10.0% forest land cover as of 2007 (The Department of Agriculture, Fisheries, and Food, 2007). A large proportion of this afforestation took place after the mid-1980s and was fueled by government grant incentive schemes targeted at private landowners (Renou & Farrell 2005). Consequently, 54% of forests are less than 20 years old (Byrne, 2006). This specific land use change provides an opportunity for Ireland to meet international obligations set forth by the United Nations Framework Convention on Climate Change (UNFCCC, 1992). These obligations include the limitation of greenhouse gas emissions to 13% above 1990 levels. In order to promote accountability for these commitments, the UNFCCC treaty and the Kyoto Protocol (Kyoto Protocol, 1997) mandate signatories to publish greenhouse gas (GHG) emissions inventories for both greenhouse gas sources and removals by sinks. Article 3.3 of the Kyoto Protocol allows changes in C stocks due to afforestation, reforestation, and deforestation since 1990 to be used to offset inventory emissions. Therefore, due to the rapid rate of afforestation and its increased carbon sequestration since 1990, Ireland has the potential to significantly offset GHG emissions. There is little known as to the impacts of afforestation on the carbon stocks in soils over time, and even less known about the impact on Irish soils. The FORESTC project aims to analyse this impact by undertaking a nationwide study using a method similar to that of the paired plot method in Davis and Condron, 2002. The study will examine 42 forest sites across Ireland selected randomly from the National Forest Inventory (National Forest Inventory, 2007). These 42 sites will be grouped based on the forest type which includes

  15. Effects of bark beetle outbreaks and wildfire in the western US on carbon stocks during recent decades

    Science.gov (United States)

    Hicke, J. A.; Meddens, A. J.; Allen, C. D.

    2012-12-01

    Bark beetle outbreaks and wildfires are significant forest disturbances that respond strongly to climate and affect future climate through carbon cycling. Extensive tree mortality has occurred in western North America as a result of these disturbances. Here we present an analysis that quantifies impacts of these two disturbances to tree carbon stocks. Mortality area from bark beetles was derived from aerial surveys in 1997-2010 in the western US and 2001-2010 in British Columbia that were converted to mortality area by multiplying by species-specific crown areas and, in the case of the US, adjusted for underestimation. We summed moderate- and high-severity burned areas in forests from the Monitoring Trends in Burn Severity (MTBS) database from 1984-2009 to estimate mortality area from forest fires. Mortality area was then combined with spatially explicit maps of carbon stocks to estimate the amount of carbon in killed trees. Notable findings include that the mortality area from bark beetle outbreaks in the western US was comparable to the mortality area in British Columbia during the last few decades. In the western US, mortality area from bark beetles was similar to or exceeded that from forest fires. Carbon stocks in trees killed by these two disturbance types (beetles and fire) had similar spatial and temporal patterns as tree mortality, illustrating the importance of each of these disturbances in governing regional forest carbon fluxes.

  16. Content and carbon stocks in labile and recalcitrant organic matter of the soil under crop-livestock integration in Cerrado

    Directory of Open Access Journals (Sweden)

    Itaynara Batista

    2013-12-01

    Full Text Available The study of organic matter and its compartments and their relationship with management, aims to develop strategies for increasing their levels in soils and better understanding of its dynamics. This work aimed to evaluate the fractions of soil organic matter and their carbon stocks in different soil cover system in crop-livestock integration and native Cerrado vegetation. The study was conducted at the farm Cabeceira, Maracajú – MS, sample area have the following history: soybean/corn + brachiaria/cotton/oat + pasture/soybean/formation of pasture/grazing, sampling was carried out in two seasons, dry (May/2009 and rainy (March 2010, in the dry season, crops present were: pasture, corn and cotton + brachiaria and in the rainy season were corn, cotton and soybeans, so the areas in the two evaluation periods were: pasture / maize + brachiaria / cotton, cotton / soybean area and a native of Savanna. Was performed to determine the exchangeable cations, particle size analysis, bulk density, organic carbon, particle size fractionation of organic matter of the soil with the quantification of particulate organic carbon (POC and organic carbon associated with minerals (OCam. Was also quantified the carbon stock and size fractions. The area of pasture / maize showed higher carbon stock in the particulate fraction in the topsoil. The area of cotton / soy due to its lower clay, showed the greatest loss of carbon. Because of the areas have the same history, the stock of more recalcitrant fraction was not sensitive to variations in coverage. The POC fraction appears more sensitive to different soil covers and seasonality.

  17. Ability of LANDSAT-8 Oli Derived Texture Metrics in Estimating Aboveground Carbon Stocks of Coppice Oak Forests

    Science.gov (United States)

    Safari, A.; Sohrabi, H.

    2016-06-01

    The role of forests as a reservoir for carbon has prompted the need for timely and reliable estimation of aboveground carbon stocks. Since measurement of aboveground carbon stocks of forests is a destructive, costly and time-consuming activity, aerial and satellite remote sensing techniques have gained many attentions in this field. Despite the fact that using aerial data for predicting aboveground carbon stocks has been proved as a highly accurate method, there are challenges related to high acquisition costs, small area coverage, and limited availability of these data. These challenges are more critical for non-commercial forests located in low-income countries. Landsat program provides repetitive acquisition of high-resolution multispectral data, which are freely available. The aim of this study was to assess the potential of multispectral Landsat 8 Operational Land Imager (OLI) derived texture metrics in quantifying aboveground carbon stocks of coppice Oak forests in Zagros Mountains, Iran. We used four different window sizes (3×3, 5×5, 7×7, and 9×9), and four different offsets ([0,1], [1,1], [1,0], and [1,-1]) to derive nine texture metrics (angular second moment, contrast, correlation, dissimilar, entropy, homogeneity, inverse difference, mean, and variance) from four bands (blue, green, red, and infrared). Totally, 124 sample plots in two different forests were measured and carbon was calculated using species-specific allometric models. Stepwise regression analysis was applied to estimate biomass from derived metrics. Results showed that, in general, larger size of window for deriving texture metrics resulted models with better fitting parameters. In addition, the correlation of the spectral bands for deriving texture metrics in regression models was ranked as b4>b3>b2>b5. The best offset was [1,-1]. Amongst the different metrics, mean and entropy were entered in most of the regression models. Overall, different models based on derived texture metrics

  18. Greater carbon stocks and faster turnover rates with increasing agricultural productivity

    Science.gov (United States)

    Sanderman, J.; Fallon, S.; Baisden, T. W.

    2013-12-01

    H.H. Janzen (2006) eloquently argued that from an agricultural perspective there is a tradeoff between storing carbon as soil organic matter (SOM) and the soil nutrient and energy benefit provided during SOM mineralization. Here we report on results from the Permanent Rotation Trial at the Waite Agricultural Institute, South Australia, indicating that shifting to an agricultural management strategy which returns more carbon to the soil, not only leads to greater carbon stocks but also increases the rate of carbon cycling through the soil. The Permanent Rotation Trial was established on a red Chromosol in 1925 with upgrades made to several treatments in 1948. Decadal soil samples were collected starting in 1963 at two depths, 0-10 and 10-22.5 cm, by compositing 20 soil cores taken along the length of each plot. We have chosen to analyze five trials representing a gradient in productivity: permanent pasture (Pa), wheat-pasture rotation (2W4Pa), continuous wheat (WW), wheat-oats-fallow rotation (WOF) and wheat-fallow (WF). For each of the soil samples (40 in total), the radiocarbon activity in the bulk soil as well as size-fractionated samples was measured by accelerator mass spectrometry at ANU's Radiocarbon Dating Laboratory (Fallon et al. 2010). After nearly 70 years under each rotation, SOC stocks increased linearly with productivity data across the trials from 24 to 58 tC ha-1. Importantly, these differences were due to greater losses over time in the low productivity trials rather than gains in SOC in any of the trials. Uptake of the bomb-spike in atmospheric 14C into the soil was greatest in the trials with the greatest productivity. The coarse size fraction always had greater Δ14C values than the bulk soil samples. Several different multi-pool steady state and non-steady state models were used to interpret the Δ14C data in terms of SOC turnover rates. Regardless of model choice, either the decay rates of all pools needed to increase or the allocation of C to

  19. ORGANIC CARBON CONTENTS AND STOCKS IN PARTICLE SIZE FRACTIONS OF A TYPIC HAPLUDOX FERTILIZED WITH PIG SLURRY AND SOLUBLE FERTILIZER

    OpenAIRE

    Maria Sueli Heberle Mafra; Paulo Cezar Cassol; Jackson Adriano Albuquerque; Marco André Grohskopf; Andreia Patrícia Andrade; Luiz Paulo Rauber; Augusto Friederichs

    2015-01-01

    The use of pig slurry (PS) as fertilizer can affect the soil quality and increase total stocks of soil organic carbon (TOC). However, the effects of PS on TOC amount and forms in the soil are not fully understood, particularly in areas under no-tillage (NT). The purpose of this study was to determine TOC contents and stocks in the particulate (POC) and mineral-associated C fractions (MAC) of an Oxisol after nine years of maize-oat rotation under NT, with annual applications of PS, soluble fer...

  20. Local spatial structure of forest biomass and its consequences for remote sensing of carbon stocks

    Directory of Open Access Journals (Sweden)

    M. Réjou-Méchain

    2014-04-01

    Full Text Available Advances in forest carbon mapping have the potential to greatly reduce uncertainties in the global carbon budget and to facilitate effective emissions mitigation strategies such as REDD+. Though broad scale mapping is based primarily on remote sensing data, the accuracy of resulting forest carbon stock estimates depends critically on the quality of field measurements and calibration procedures. The mismatch in spatial scales between field inventory plots and larger pixels of current and planned remote sensing products for forest biomass mapping is of particular concern, as it has the potential to introduce errors, especially if forest biomass shows strong local spatial variation. Here, we used 30 large (8–50 ha globally distributed permanent forest plots to quantify the spatial variability in aboveground biomass (AGB at spatial grains ranging from 5 to 250 m (0.025–6.25 ha, and we evaluate the implications of this variability for calibrating remote sensing products using simulated remote sensing footprints. We found that the spatial sampling error in AGB is large for standard plot sizes, averaging 46.3% for 0.1 ha subplots and 16.6% for 1 ha subplots. Topographically heterogeneous sites showed positive spatial autocorrelation in AGB at scales of 100 m and above; at smaller scales, most study sites showed negative or nonexistent spatial autocorrelation in AGB. We further show that when field calibration plots are smaller than the remote sensing pixels, the high local spatial variability in AGB leads to a substantial "dilution" bias in calibration parameters, a bias that cannot be removed with current statistical methods. Overall, our results suggest that topography should be explicitly accounted for in future sampling strategies and that much care must be taken in designing calibration schemes if remote sensing of forest carbon is to achieve its promise.

  1. Imputing forest carbon stock estimates from inventory plots to a nationally continuous coverage

    Directory of Open Access Journals (Sweden)

    Wilson Barry Tyler

    2013-01-01

    Full Text Available Abstract The U.S. has been providing national-scale estimates of forest carbon (C stocks and stock change to meet United Nations Framework Convention on Climate Change (UNFCCC reporting requirements for years. Although these currently are provided as national estimates by pool and year to meet greenhouse gas monitoring requirements, there is growing need to disaggregate these estimates to finer scales to enable strategic forest management and monitoring activities focused on various ecosystem services such as C storage enhancement. Through application of a nearest-neighbor imputation approach, spatially extant estimates of forest C density were developed for the conterminous U.S. using the U.S.’s annual forest inventory. Results suggest that an existing forest inventory plot imputation approach can be readily modified to provide raster maps of C density across a range of pools (e.g., live tree to soil organic carbon and spatial scales (e.g., sub-county to biome. Comparisons among imputed maps indicate strong regional differences across C pools. The C density of pools closely related to detrital input (e.g., dead wood is often highest in forests suffering from recent mortality events such as those in the northern Rocky Mountains (e.g., beetle infestations. In contrast, live tree carbon density is often highest on the highest quality forest sites such as those found in the Pacific Northwest. Validation results suggest strong agreement between the estimates produced from the forest inventory plots and those from the imputed maps, particularly when the C pool is closely associated with the imputation model (e.g., aboveground live biomass and live tree basal area, with weaker agreement for detrital pools (e.g., standing dead trees. Forest inventory imputed plot maps provide an efficient and flexible approach to monitoring diverse C pools at national (e.g., UNFCCC and regional scales (e.g., Reducing Emissions from Deforestation and Forest

  2. Estimating Carbon Stocks and Atmospheric Exchange of Depressional Marshes on the Central Florida Landscape

    Science.gov (United States)

    Benscoter, B.; McClellan, M. D.; Benavides, V.; Harshbarger, D.; Comas, X.

    2014-12-01

    Depressional marshes are ubiquitous throughout central and south Florida. Often distributed within a matrix of sandy pine flatwoods and hammocks, these wetlands have a seasonally variable water table, alternating between inundation and complete drydown. Though these landforms are typically small individually, they comprise a substantial component of the landscape and provide vital habitat for an array of flora and fauna. Given their fluctuating hydrology, conditions for soil and plant carbon (C) exchange mechanisms can vary greatly both spatially and temporally. In this study, we are developing a C budget for depressional marsh landforms by assessing ecosystem carbon exchange along an ecotone gradient and quantifying belowground C stocks using non-invasive geophysical methods (ground penetrating radar, GPR) at the Disney Wilderness Preserve (DWP) in Kissimmee, FL, USA. Using a series of closed chambers transecting the marsh from the center outward into the surrounding flatwoods, we are quantifying the effects of seasonal water table change on the magnitude of C exchange. Three dimensional GPR surveys were used to quantify peat layer thickness, and were constrained with direct core sampling to verify subsurface lithology and to assess peat C content. Using the relationship between landform surface area and belowground C volume, we assessed the cumulative C storage in depressional marshes across the DWP landscape. In conjunction with a nearby eddy covariance tower and seasonal hydrologic data, these response functions will help to evaluate the contribution of these small but widespread landscape features on regional C cycling.

  3. Carbon stock in Korean larch plantations along a chronosequence in the Lesser Khingan Mountains, China

    Institute of Scientific and Technical Information of China (English)

    Wei MA; Yan-hong LIU; Yu-jun SUN; Jason Grabosky

    2014-01-01

    Carbon (C) dynamics are central to understanding ecosystem restoration effects within the context of Grain for Green Project (GGP). GGP stared in China since 2003 to improve the environment. Despite its importance, how total forest ecosystem C stock (FECS) develops fol-lowing land-use changes from cropland to plantation is poorly under-stood, in particular the relationship of C allocation to pools. We quanti-fied C pools in a chronosequence ranging from 0 to 48 years, using com-plete above-and below-ground harvests based on detailed field inventory. Stands were chosen along a succession sequence in managed plantations of Korean larch (Larix olgensis Henry.), a native planting species in the Lesser Khingan Mountains, Northeast of China. The FECS of Korean larch plantation (KLP) were dynamic across stand development, chang-ing from 88.2 Mg·ha-1 at cropland, to 183.9 Mg·ha-1 as an average of forest C from 7-through 48-year-old plantation. In a 48-year-old mature KLP, vegetation comprises 48.63%of FECS and accounts for 67.66%of annual net C increment (ANCI). Soil is responsible for 38.19% and 13.53% of those, and with the remainders of 13.18% and 18.81% in down woody materials. Based on comparisons of our estimate to those of others, we conclude that afforestation of Korean larch plantation is a valid approach to sequester carbon.

  4. Conventional tillage vs. organic farming in relation to soil organic carbon stock in olive groves in Mediterranean rangelands (Southern Spain)

    Science.gov (United States)

    Parras-Alcántara, L.; Lozano-García, B.

    2014-01-01

    Soil organic carbon (SOC) concentration is a soil variable subject to changes. In agricultural soils, the management system is a key factor that influence to these changes. For determine the management system effects on SOC stocks (SOC-S) in olive groves, 114 soil profiles were studied in the Los Pedroches Valley (Mediterranean rangelands - southern Spain) for long-term (20 yr). The management practices were conventional tillage (CT) and organic farming (OF) in four soil types: Cambisols (CM), Regosols (RG), Luvisols (LV) and Leptosols (LP). Soil properties were statistically analyzed by management techniques, soil types and horizons. The principal components analyses identified four factors that explained 65% of the variance. Also, significant differences (p soil types and management techniques. Equally was observed that the management system affected to SOC-S. In addition, the total SOC-S for 20 yr increased in OF with respect to CT by 72% and 66% in CM and LV respectively. The SOC showed significant differences for horizons (p 2 in all studied soils. These results indicate high soils quality, and that management practices affect to SOC store in the Los Pedroches Valley.

  5. An investigation on important factors influencing on forecasted earnings adjustment: Evidence from Tehran Stock Exchange

    Directory of Open Access Journals (Sweden)

    Fatemeh Babakhani

    2014-01-01

    Full Text Available This paper presents an empirical investigation to detect important factors influencing earning adjustment on firms selected on Tehran Stock Exchange over the period 2006-2011. There are four independent variables associated with the proposed study of this paper including Proportion of shares owned by institutional investors, Return on assets, Profit change and Market value to book value. In addition, Investment restructuring is considered as control variable. The results of the implementation of regression analysis indicate that there was a reverse relationship between earning forecasted adjustment and two independent variables including size of firm as well as the ratio of market value to book value. However, Net profit has a direct and positive relationship with earning forecast adjustment.

  6. Carbon stocks of trees killed by bark beetles and wildfire in the western United States

    International Nuclear Information System (INIS)

    Forests are major components of the carbon cycle, and disturbances are important influences of forest carbon. Our objective was to contribute to the understanding of forest carbon cycling by quantifying the amount of carbon in trees killed by two disturbance types, fires and bark beetles, in the western United States in recent decades. We combined existing spatial data sets of forest biomass, burn severity, and beetle-caused tree mortality to estimate the amount of aboveground and belowground carbon in killed trees across the region. We found that during 1984–2010, fires killed trees that contained 5–11 Tg C year−1 and during 1997–2010, beetles killed trees that contained 2–24 Tg C year−1, with more trees killed since 2000 than in earlier periods. Over their periods of record, amounts of carbon in trees killed by fires and by beetle outbreaks were similar, and together these disturbances killed trees representing 9% of the total tree carbon in western forests, a similar amount to harvesting. Fires killed more trees in lower-elevation forest types such as Douglas-fir than higher-elevation forest types, whereas bark beetle outbreaks also killed trees in higher-elevation forest types such as lodgepole pine and Engelmann spruce. Over 15% of the carbon in lodgepole pine and spruce/fir forest types was in trees killed by beetle outbreaks; other forest types had 5–10% of the carbon in killed trees. Our results document the importance of these natural disturbances in the carbon budget of the western United States. (letter)

  7. Carbon stocks of trees killed by bark beetles and wildfire in the western United States

    Science.gov (United States)

    Hicke, Jeffrey A.; Meddens, Arjan J.H.; Allen, Craig D.; Kolden, Crystal A.

    2013-01-01

    Forests are major components of the carbon cycle, and disturbances are important influences of forest carbon. Our objective was to contribute to the understanding of forest carbon cycling by quantifying the amount of carbon in trees killed by two disturbance types, fires and bark beetles, in the western United States in recent decades. We combined existing spatial data sets of forest biomass, burn severity, and beetle-caused tree mortality to estimate the amount of aboveground and belowground carbon in killed trees across the region. We found that during 1984-2010, fires killed trees that contained 5-11 Tg C year-1 and during 1997-2010, beetles killed trees that contained 2-24 Tg C year-1, with more trees killed since 2000 than in earlier periods. Over their periods of record, amounts of carbon in trees killed by fires and by beetle outbreaks were similar, and together these disturbances killed trees representing 9% of the total tree carbon in western forests, a similar amount to harvesting. Fires killed more trees in lower-elevation forest types such as Douglas-fir than higher-elevation forest types, whereas bark beetle outbreaks also killed trees in higher-elevation forest types such as lodgepole pine and Engelmann spruce. Over 15% of the carbon in lodgepole pine and spruce/fir forest types was in trees killed by beetle outbreaks; other forest types had 5-10% of the carbon in killed trees. Our results document the importance of these natural disturbances in the carbon budget of the western United States.

  8. How surface fire in Siberian Scots pine forests affects soil organic carbon in the forest floor: Stocks, molecular structure, and conversion to black carbon (charcoal)

    OpenAIRE

    Czimczik, Claudia I; Preston, Caroline M; Schmidt, Michael W I; Schulze, Ernst-Detlef

    2003-01-01

    [1] In boreal forests, fire is a frequent disturbance and converts soil organic carbon (OC) to more degradation-resistant aromatic carbon, i.e., black carbon (BC) which might act as a long-term atmospheric-carbon sink. Little is known on the effects of fires on boreal soil OC stocks and molecular composition. We studied how a surface fire affected the composition of the forest floor of Siberian Scots pine forests by comparing the bulk elemental composition, molecular structure (13C-MAS NMR), ...

  9. Alpine grassland soil organic carbon stock and its uncertainty in the three rivers source region of the Tibetan Plateau.

    Directory of Open Access Journals (Sweden)

    Xiaofeng Chang

    Full Text Available Alpine grassland of the Tibetan Plateau is an important component of global soil organic carbon (SOC stocks, but insufficient field observations and large spatial heterogeneity leads to great uncertainty in their estimation. In the Three Rivers Source Region (TRSR, alpine grasslands account for more than 75% of the total area. However, the regional carbon (C stock estimate and their uncertainty have seldom been tested. Here we quantified the regional SOC stock and its uncertainty using 298 soil profiles surveyed from 35 sites across the TRSR during 2006-2008. We showed that the upper soil (0-30 cm depth in alpine grasslands of the TRSR stores 2.03 Pg C, with a 95% confidence interval ranging from 1.25 to 2.81 Pg C. Alpine meadow soils comprised 73% (i.e. 1.48 Pg C of the regional SOC estimate, but had the greatest uncertainty at 51%. The statistical power to detect a deviation of 10% uncertainty in grassland C stock was less than 0.50. The required sample size to detect this deviation at a power of 90% was about 6-7 times more than the number of sample sites surveyed. Comparison of our observed SOC density with the corresponding values from the dataset of Yang et al. indicates that these two datasets are comparable. The combined dataset did not reduce the uncertainty in the estimate of the regional grassland soil C stock. This result could be mainly explained by the underrepresentation of sampling sites in large areas with poor accessibility. Further research to improve the regional SOC stock estimate should optimize sampling strategy by considering the number of samples and their spatial distribution.

  10. Alpine grassland soil organic carbon stock and its uncertainty in the three rivers source region of the Tibetan Plateau.

    Science.gov (United States)

    Chang, Xiaofeng; Wang, Shiping; Cui, Shujuan; Zhu, Xiaoxue; Luo, Caiyun; Zhang, Zhenhua; Wilkes, Andreas

    2014-01-01

    Alpine grassland of the Tibetan Plateau is an important component of global soil organic carbon (SOC) stocks, but insufficient field observations and large spatial heterogeneity leads to great uncertainty in their estimation. In the Three Rivers Source Region (TRSR), alpine grasslands account for more than 75% of the total area. However, the regional carbon (C) stock estimate and their uncertainty have seldom been tested. Here we quantified the regional SOC stock and its uncertainty using 298 soil profiles surveyed from 35 sites across the TRSR during 2006-2008. We showed that the upper soil (0-30 cm depth) in alpine grasslands of the TRSR stores 2.03 Pg C, with a 95% confidence interval ranging from 1.25 to 2.81 Pg C. Alpine meadow soils comprised 73% (i.e. 1.48 Pg C) of the regional SOC estimate, but had the greatest uncertainty at 51%. The statistical power to detect a deviation of 10% uncertainty in grassland C stock was less than 0.50. The required sample size to detect this deviation at a power of 90% was about 6-7 times more than the number of sample sites surveyed. Comparison of our observed SOC density with the corresponding values from the dataset of Yang et al. indicates that these two datasets are comparable. The combined dataset did not reduce the uncertainty in the estimate of the regional grassland soil C stock. This result could be mainly explained by the underrepresentation of sampling sites in large areas with poor accessibility. Further research to improve the regional SOC stock estimate should optimize sampling strategy by considering the number of samples and their spatial distribution. PMID:24819054

  11. A National, Detailed Map of Forest Aboveground Carbon Stocks in Mexico

    Directory of Open Access Journals (Sweden)

    Oliver Cartus

    2014-06-01

    Full Text Available A spatially explicit map of aboveground carbon stored in Mexico’s forests was generated from empirical modeling on forest inventory and spaceborne optical and radar data. Between 2004 and 2007, the Mexican National Forestry Commission (CONAFOR established a network of ~26,000 permanent inventory plots in the frame of their national inventory program, the Inventario Nacional Forestal y de Suelos (INFyS. INFyS data served as model response for spatially extending the field-based estimates of carbon stored in the aboveground live dry biomass to a wall-to-wall map, with 30 × 30 m2 pixel posting using canopy density estimates derived from Landsat, L-Band radar data from ALOS PALSAR, as well as elevation information derived from the Shuttle Radar Topography Mission (SRTM data set. Validation against an independent set of INFyS plots resulted in a coefficient of determination (R2 of 0.5 with a root mean square error (RMSE of 14 t∙C/ha in the case of flat terrain. The validation for different forest types showed a consistently low estimation bias (<3 t∙C/ha and R2s in the range of 0.5 except for mangroves (R2 = 0.2. Lower accuracies were achieved for forests located on steep slopes (>15° with an R2 of 0.34. A comparison of the average carbon stocks computed from: (a the map; and (b statistical estimates from INFyS, at the scale of ~650 km2 large hexagons (R2 of 0.78, RMSE of 5 t∙C/ha and Mexican states (R2 of 0.98, RMSE of 1.4 t∙C/ha, showed strong agreement.

  12. Impacts of Jatropha-based biodiesel production on above and below-ground carbon stocks: A case study from Mozambique

    International Nuclear Information System (INIS)

    The need to mitigate climate change makes production of liquid biofuels a high priority. Substituting fossil fuels by biodiesel produced from Jatropha curcas has gained widespread attention as Jatropha cultivation is claimed to offer green house gas emission reductions. Farmers respond worldwide to this increasing demand by converting forests into Jatropha, but whether Jatropha-based biodiesel offers carbon savings depends on the carbon emissions that occur when land use is changed to Jatropha. This paper provides an impact assessment of a small-scale Jatropha project in Cabo Delgado, Mozambique. The paper outlines the estimated impacts on above and below-ground carbon stocks when land use is changed to increase Jatropha production. The results show that expansion of Jatropha production will most likely lead to the conversion of miombo forest areas to Jatropha, which implies a reduction in above and below-ground carbon stocks. The carbon debts created by the land use change can be repaid by replacing fossil fuels with Jatropha-based biodiesel. A repayment time of almost two centuries is found with optimistic estimates of the carbon debt, while the use of pessimistic values results in a repayment time that approaches the millennium. - Highlights: ► Demands for biofuels make production of Jatropha-based biodiesel a priority. ► Farmers in Northern Mozambique are likely to convert un-logged miombo to Jatropha. ► Converting miombo to Jatropha creates reductions in above and below-ground carbon. ► It takes 187–966 years to repay emissions from above and below-ground carbon stocks.

  13. A new baseline of organic carbon stock in European agricultural soils using a modelling approach.

    Science.gov (United States)

    Lugato, Emanuele; Panagos, Panos; Bampa, Francesca; Jones, Arwyn; Montanarella, Luca

    2014-01-01

    Proposed European policy in the agricultural sector will place higher emphasis on soil organic carbon (SOC), both as an indicator of soil quality and as a means to offset CO2 emissions through soil carbon (C) sequestration. Despite detailed national SOC data sets in several European Union (EU) Member States, a consistent C stock estimation at EU scale remains problematic. Data are often not directly comparable, different methods have been used to obtain values (e.g. sampling, laboratory analysis) and access may be restricted. Therefore, any evolution of EU policies on C accounting and sequestration may be constrained by a lack of an accurate SOC estimation and the availability of tools to carry out scenario analysis, especially for agricultural soils. In this context, a comprehensive model platform was established at a pan-European scale (EU + Serbia, Bosnia and Herzegovina, Croatia, Montenegro, Albania, Former Yugoslav Republic of Macedonia and Norway) using the agro-ecosystem SOC model CENTURY. Almost 164 000 combinations of soil-climate-land use were computed, including the main arable crops, orchards and pasture. The model was implemented with the main management practices (e.g. irrigation, mineral and organic fertilization, tillage) derived from official statistics. The model results were tested against inventories from the European Environment and Observation Network (EIONET) and approximately 20 000 soil samples from the 2009 LUCAS survey, a monitoring project aiming at producing the first coherent, comprehensive and harmonized top-soil data set of the EU based on harmonized sampling and analytical methods. The CENTURY model estimation of the current 0-30 cm SOC stock of agricultural soils was 17.63 Gt; the model uncertainty estimation was below 36% in half of the NUTS2 regions considered. The model predicted an overall increase of this pool according to different climate-emission scenarios up to 2100, with C loss in the south and east of the area

  14. Biomass and Soil Carbon Stocks in Wet Montane Forest, Monteverde Region, Costa Rica: Assessments and Challenges for Quantifying Accumulation Rates

    Directory of Open Access Journals (Sweden)

    Lawrence H. Tanner

    2016-01-01

    Full Text Available We measured carbon stocks at two forest reserves in the cloud forest region of Monteverde, comparing cleared land, experimental secondary forest plots, and mature forest at each location to assess the effectiveness of reforestation in sequestering biomass and soil carbon. The biomass carbon stock measured in the mature forest at the Monteverde Institute is similar to other measurements of mature tropical montane forest biomass carbon in Costa Rica. Local historical records and the distribution of large trees suggest a mature forest age of greater than 80 years. The forest at La Calandria lacks historical documentation, and dendrochronological dating is not applicable. However, based on the differences in tree size, above-ground biomass carbon, and soil carbon between the Monteverde Institute and La Calandria sites, we estimate an age difference of at least 30 years of the mature forests. Experimental secondary forest plots at both sites have accumulated biomass at lower than expected rates, suggesting local limiting factors, such as nutrient limitation. We find that soil carbon content is primarily a function of time and that altitudinal differences between the study sites do not play a role.

  15. Carbon and biomass stocks in a fragment of cerradão in Minas Gerais state, Brazil

    Directory of Open Access Journals (Sweden)

    Vinícius Augusto Morais

    2013-06-01

    Full Text Available This study aimed at quantifying carbon (C and biomass stocks in shoot portion, leaf litter, roots and soil within a fragment of dense savanna 'cerradão', 158.5 ha in area, located in Minas Gerais state. Measures were quantified using dendrometric parameters obtained during the forest inventory and collection of leaf litter, root and soil samples. Furrows were dug in the soil each 100 cm long, 50 cm wide and 100 cm deep in order to collect root samples at depths of 0-30 cm, 30-50 cm and 50-100 cm, and soil samples from the layers 0-10 cm, 10-20 cm, 20-40 cm, 40-60 cm and 60-100 cm, as well as any leaf litter from the surrounding surface. Analyses were performed in the Organic Matter Study Laboratory (DCS/UFLA to determine C contents in the above matrices, using an Elementar analyzer model Vario TOC Cube. Higher C contents and stocks and lower density were noted in topmost soil layers. In cerradão, shoot portion was found to be the matrix contributing the most to biomass production, followed by roots and leaf litter. Carbon stock in the fragment was 139.7 Mg ha-1. Soil was the matrix contributing the most to stocked C (64.8%, followed by the shoot portion (26.3%, roots (5.2% and leaf litter (3.7%.

  16. Impacts of a changing fire frequency on soil carbon stocks in interior Alaskan boreal forests

    Science.gov (United States)

    Hoy, E.; Kasischke, E. S.

    2011-12-01

    spruce forests it will be possible to better model carbon stocks throughout the region.

  17. CARBON STOCK IN SOIL UNDER DIFFERENT FOREST FORMATIONS, CHAPECÓ, SANTA CATARINA STATE

    Directory of Open Access Journals (Sweden)

    Rosiane Berenice Nicoloso Denardin

    2014-03-01

    Full Text Available http://dx.doi.org/10.5902/1980509813323The adoption of management practices that ensure the stability of soil organic matter also maintain the stabilityor quantitative increase of carbon (C in the lithosphere, reducing the amount of CO2 in theatmosphere. You can also minimize the losses of C to the atmosphere by using conservation practices,or using cover crops to keep the soil C stocks, and the forest cover are considered great abductionand forest systems considered large reservoirs of C. This work was performed on a property located inChapecó, Santa Catarina state, where soils were sampled from different forest formations distributedin a homogeneous soil range. The local climate is mesothermal, rainy, and the soil was characterizedas an association Cambissolo Háplico/Neossolo Litólico. The objectives were to estimate the C stocksin soils and estimate the C losses occurred due to the change of soil cover. It was evaluated soils undernatural forest (FN, of secondary stage, with a high degree of preservation; planted forest of eucalyptus(Eucalyptus saligna (PE, with eight years of cultivation, preceded by 17 years under crop conventionaltillage; and a planted forest of herb mate (Ilex paraguariensis (EM, with 25 years of cultivation underconventional system (cutting interval of 18 months, with removal of all waste produced and maintenanceof the ground without cover, with periodic use of herbicide - glyphosate. In each area were opened fourtrenches with 50 cm deep, where soil samples were collected in depths of: 0-5 cm, 5-10 cm, 10-20 cm,20-30 cm, 30-40 cm, and 40-50 cm, with kopeck rings. It was possible to determine the bulk density (Mgm-3, the soil volume per layer (depth and per hectare, and the concentration of soil C in the differentstudied areas. To quantify the C stocks equal amounts of soil were used for each depth evaluated. Itwas observed higher densities of soils and under PE and EM, to FN the lowest density are explained bythe

  18. Ecuador's mangrove forest carbon stocks: A spatiotemporal analysis of living carbon holdings and their depletion since the advent of commercial aquaculture

    CERN Document Server

    Hamilton, Stuart

    2014-01-01

    In this paper we estimate the living carbon lost from Ecuador's mangrove forests since the advent of export-focused shrimp aquaculture. We use remote sensing techniques to delineate the extent of mangroves and aquaculture at approximately decadal periods since the arrival of aquaculture in each Ecuadorian estuary. We then spatiotemporally calculate the carbon values of the mangrove forests and estimate the amount of carbon lost due to direct displacement by aquaculture. Additionally, we calculate the new carbon stocks generated due to mangrove reforestation or afforestation. This research introduces time and land use / land cover change (LUCC) into the tropical forest carbon literature and examines forest carbon loss at a higher spatiotemporal resolution than in many earlier analyses. We find that 80%, or 7,014,517 t of the living carbon lost in Ecuadorian mangrove forests can be attributed to direct displacement of mangrove forests by shrimp aquaculture. We also find that Intergovernmental Panel on Climate C...

  19. Community Monitoring of Carbon Stocks for REDD+: Does Accuracy and Cost Change over Time?

    Directory of Open Access Journals (Sweden)

    Søren Brofeldt

    2014-07-01

    Full Text Available Reducing emissions from deforestation and forest degradation in developing countries, and the role of conservation, sustainable management of forests, and enhancement of forest carbon stocks in developing countries (REDD+ is a potentially powerful international policy mechanism that many tropical countries are working towards implementing. Thus far, limited practical consideration has been paid to local rights to forests and forest resources in REDD+ readiness programs, beyond noting the importance of these issues. Previous studies have shown that community members can reliably and cost-effectively monitor forest biomass. At the same time, this can improve local ownership and forge important links between monitoring activities and local decision-making. Existing studies have, however, been static assessments of biomass at one point in time. REDD+ programs will require repeated surveys of biomass over extended time frames. Here, we examine trends in accuracy and costs of local forest monitoring over time. We analyse repeated measurements by community members and professional foresters of 289 plots over two years in four countries in Southeast Asia. This shows, for the first time, that with repeated measurements community members’ biomass measurements become increasingly accurate and costs decline. These findings provide additional support to available evidence that community members can play a strong role in monitoring forest biomass in the local implementation of REDD+.

  20. Scenarios of Future Climate and Land-Management Effects on Carbon Stocks in Northern Patagonian Shrublands

    Science.gov (United States)

    Carrera, Analia; Ares, Jorge; Labraga, Juan; Thurner, Stephanie; Bertiller, Mónica

    2007-12-01

    We analyzed the possible effects of grazing management and future climate change on carbon (C) stocks in soils of northern Patagonian shrublands. To this aim, we coupled the outputs of three (HadCM3, CSIRO Mk2, and CCSR/NIES) global climate models to the CENTURY (v5.3) model of terrestrial C balance. The CENTURY model was initialized with long-term field data on local biome physiognomy, seasonal phenologic trends, and prevailing land-management systems and was validated with recent sequences of 1-km Normalized Difference Vegetation Index (MODIS-Terra) images and soil C data. In the tested scenarios, the predicted climate changes would result in increased total C in soil organic matter (SOMTC). Maximum SOMTC under changed climate forcing would not differ significantly from that expected under baseline conditions (8 kg m-2). A decrease in grazing intensity would result in SOMTC increases of 11% to 12% even if climate changes did not occur. Climate change would account for SOMTC increases of 5% to 6%.

  1. Site Productivity and Forest Carbon Stocks in the United States: Analysis and Implications for Forest Offset Project Planning

    Directory of Open Access Journals (Sweden)

    James E. Smith

    2012-06-01

    Full Text Available The documented role of United States forests in sequestering carbon, the relatively low cost of forest-based mitigation, and the many co-benefits of increasing forest carbon stocks all contribute to the ongoing trend in the establishment of forest-based carbon offset projects. We present a broad analysis of forest inventory data using site quality indicators to provide guidance to managers planning land acquisition for forest-based greenhouse gas mitigation projects. Specifically, we summarize two condition class indicators of site productivity within the FIA forest inventory database—physclcd and siteclcd—as they relate to current aboveground live tree carbon stocks. Average carbon density is higher on more productive sites, but compared to the overall variability among sites, the differences are relatively small for all but the highest and lowest site classes. Some minor differences in eastern- versus western-forests were apparent in terms of how carbon on the least productive sites differed from most other forest land over time. Overall results suggest that xeric sites in most regions as well as sites that correspond to the lowest, non-productive classifications of forest land should preferentially not be used forestry-based greenhouse gas mitigation projects, but all other forest areas appear to be suitable.

  2. Chemical attributes, total organic carbon stock and humified fractions of organic matter soil submitted to different systems of sugarcane management

    OpenAIRE

    Jean Sérgio Rosset; Jolimar Antonio Schiavo; Ricardo Augusto Rezende Atanázio

    2014-01-01

    Mechanized harvesting maintenance of trash from cane sugar and soil application of waste as vinasse and filter cake can improve the system of crop yield. Thus, this study aimed to evaluate the changes in the chemical, the stock of total organic carbon and humified organic matter fractions in an Oxisol cultivated with cane sugar with the following management systems: with sugarcane vinasse application (CCV), without application of burnt cane waste (CQS), with burnt cane vinasse application (CQ...

  3. Content and carbon stocks in labile and recalcitrant organic matter of the soil under crop-livestock integration in Cerrado

    OpenAIRE

    Itaynara Batista; Marcos Gervasio Pereira; Maria Elizabeth Fernandes Correia; Wanderlei Bieluczyk; Jolimar Antônio Schiavo; Janaína Ribeiro Costa Rows

    2013-01-01

    The study of organic matter and its compartments and their relationship with management, aims to develop strategies for increasing their levels in soils and better understanding of its dynamics. This work aimed to evaluate the fractions of soil organic matter and their carbon stocks in different soil cover system in crop-livestock integration and native Cerrado vegetation. The study was conducted at the farm Cabeceira, Maracajú – MS, sample area have the following history: soybean/corn + brac...

  4. Development of carbon stocks in post-agrogenic, self-restorating soils of different climatic zones of Russia

    Science.gov (United States)

    Kalinina, Olga; Goryachkin, Sergey; Lyuri, Dmitriy; Giani, Luise

    2013-04-01

    The focus of this chronosequential study was on dynamics of soil organic carbon (SOC) stocks of post-agrogenic soils under self-restoration of Russia: Podzols and Stagnic Albeluvisols of the taiga, Chernozems of the forest-steppe, Calcisols and Solonetz of the dry steppe. The sites of each chronosequence were comparable in climate, texture, and land-use history, but differed in duration of self-restoration. In the Podzol and Stagnic Albeluvisol chronosequences, the carbon stocks showed a distinct redistribution within different soil sections. Hence, during 170 years of a Podzol chronosequence, the carbon (C) accumulated in the organic surface layers up to 3.3 kg m-2, but C decreased in 0 - 0.2m of the mineral topsoils from 4.3 to 3.1 kg m-2 and in 0.2 - 0.5m of the mineral topsoils from 4.6 to 2.1 kg m-2. Decreasing SOC stocks of the mineral soils were overcompensated by increasing SOC stores of the organic surface layers, thus showing an increasing SOC sink functioning. During 68 years of a Stagnic Albeluvisol self-restoration, C accumulated in the organic surface layers up to 0.8 kg m-2 and in 0 - 0.2m of the mineral topsoils from 2.2 to 3.2 kg m-2, but C decreased in 0.2 - 0.5m of the mineral topsoils from 2.2 to 0.7 kg m-2. Decreasing SOC stocks of 0.2 - 0.5m sections of the mineral soils were compensated by increasing SOC stores of the organic surface layers and 0 - 0.2m section of the mineral topsoils. This indicates a tendency of an increasing SOM sink functioning at long terms. An increasing C sink was determined for the other chronosequences. Hence, during 59 years of Chernozem self-restoration, SOC stocks increased from 6.2 to 9.4 kg m-2 in the upper 0.2m and from 17.7 to 24.2 kg m-2 in the upper 0.5m and reached 76% and 95% of the C stocks of the natural Chernozem, respectively. During 42 years of Calcisol chronosequence, SOC stocks increased from 1.1 to 1.3 kg m-2 in the upper 0.2m and from 2.0 to 3.5 in the upper 0.5m and reached 42 and 79% of the C

  5. Estimating urban trees and carbon stock potentials for mitigating climate change in Lagos: Case of Ikeja Government Reserved Area (GRA)

    Science.gov (United States)

    Elias, P. O.; Faderin, A.

    2014-12-01

    Urban trees are a component of the urban infrastructure which offers diverse services including environmental, aesthetic and economic. The accumulation of carbon in the atmosphere resulting from the indiscriminate distribution of human populations and urban activities with the unsustainable consumption of natural resources contributes to global environmental change especially in coastal cities like Lagos. Carbon stocks and sequestration by urban trees are increasingly recognized to play significant roles for mitigating climate change. This paper focuses on the estimation of carbon stock and sequestration through biomass estimation and quantification in Ikeja GRA, Lagos. Ikeja possesses a characteristic feature as a microcosm of Lagos due to the wide range of land uses. A canopy assessment of tree population was carried out using itree canopy software. A GPS survey was used to collect an inventory of all trees showing their location, spatial distribution and other attributes. The analysis of the carbon storage and sequestration potential of both actual and potential tree planting sites involved biomass estimations from tree allometry equations. Trees were identified at species level and measurements of their dendrometric values were recorded and integrated into the GIS database to estimate biomass of trees and carbon storage. The trees in the study area were estimated to have a biomass of 441.9 mg and carbon storage of 221.395 kg/tree. By considering the potential tree planting sites the estimated carbon stored increased to 11,352.73 kg. Carbon sequestration value in the study area was found to be 1.6790 tonnes for the existing trees and 40.707 tonnes for the potential tree planting sites (PTPS). The estimation of carbon storage and sequestration values of trees are important incentives for carbon accounting/footprints and monitoring of climate change mitigation which has implications for evaluation and monitoring of urban ecosystem.

  6. Ecuador's mangrove forest carbon stocks: a spatiotemporal analysis of living carbon holdings and their depletion since the advent of commercial aquaculture.

    Science.gov (United States)

    Hamilton, Stuart E; Lovette, John

    2015-01-01

    In this paper we estimate the living carbon lost from Ecuador's mangrove forests since the advent of export-focused shrimp aquaculture. We use remote sensing techniques to delineate the extent of mangroves and aquaculture at approximately decadal periods since the arrival of aquaculture in each Ecuadorian estuary. We then spatiotemporally calculate the carbon values of the mangrove forests and estimate the amount of carbon lost due to direct displacement by aquaculture. Additionally, we calculate the new carbon stocks generated due to mangrove reforestation or afforestation. This research introduces time and LUCC (land use / land cover change) into the tropical forest carbon literature and examines forest carbon loss at a higher spatiotemporal resolution than in many earlier analyses. We find that 80 percent, or 7,014,517 t of the living carbon lost in Ecuadorian mangrove forests can be attributed to direct displacement of mangrove forests by shrimp aquaculture. We also find that IPCC (Intergovernmental Panel on Climate Change) compliant carbon grids within Ecuador's estuaries overestimate living carbon levels in estuaries where substantial LUCC has occurred. By approaching the mangrove forest carbon loss question from a LUCC perspective, these findings allow for tropical nations and other intervention agents to prioritize and target a limited set of land transitions that likely drive the majority of carbon losses. This singular cause of transition has implications for programs that attempt to offset or limit future forest carbon losses and place value on forest carbon or other forest good and services. PMID:25738286

  7. Ecuador's mangrove forest carbon stocks: a spatiotemporal analysis of living carbon holdings and their depletion since the advent of commercial aquaculture.

    Directory of Open Access Journals (Sweden)

    Stuart E Hamilton

    Full Text Available In this paper we estimate the living carbon lost from Ecuador's mangrove forests since the advent of export-focused shrimp aquaculture. We use remote sensing techniques to delineate the extent of mangroves and aquaculture at approximately decadal periods since the arrival of aquaculture in each Ecuadorian estuary. We then spatiotemporally calculate the carbon values of the mangrove forests and estimate the amount of carbon lost due to direct displacement by aquaculture. Additionally, we calculate the new carbon stocks generated due to mangrove reforestation or afforestation. This research introduces time and LUCC (land use / land cover change into the tropical forest carbon literature and examines forest carbon loss at a higher spatiotemporal resolution than in many earlier analyses. We find that 80 percent, or 7,014,517 t of the living carbon lost in Ecuadorian mangrove forests can be attributed to direct displacement of mangrove forests by shrimp aquaculture. We also find that IPCC (Intergovernmental Panel on Climate Change compliant carbon grids within Ecuador's estuaries overestimate living carbon levels in estuaries where substantial LUCC has occurred. By approaching the mangrove forest carbon loss question from a LUCC perspective, these findings allow for tropical nations and other intervention agents to prioritize and target a limited set of land transitions that likely drive the majority of carbon losses. This singular cause of transition has implications for programs that attempt to offset or limit future forest carbon losses and place value on forest carbon or other forest good and services.

  8. What moves the primary stock and bond markets? Influence of macroeconomic factors on bond and equity issues in Malaysia and Korea

    OpenAIRE

    Ameer, Rashid

    2007-01-01

    This paper examines the impact of macroeconomic factors on the stock and bond market activities in two Asian countries. We examine the influence of interest rate changes, expected inflation rate, and stock market returns on aggregate stock and bond issuance in Malaysia and Korea. Using vector autoregressive models (VARs) and variance decomposition techniques, our result show that dynamics of equity and bond issuance in both countries vary significantly. Our findings show that there has been a...

  9. ORGANIC CARBON CONTENTS AND STOCKS IN PARTICLE SIZE FRACTIONS OF A TYPIC HAPLUDOX FERTILIZED WITH PIG SLURRY AND SOLUBLE FERTILIZER

    Directory of Open Access Journals (Sweden)

    Maria Sueli Heberle Mafra

    2015-08-01

    Full Text Available The use of pig slurry (PS as fertilizer can affect the soil quality and increase total stocks of soil organic carbon (TOC. However, the effects of PS on TOC amount and forms in the soil are not fully understood, particularly in areas under no-tillage (NT. The purpose of this study was to determine TOC contents and stocks in the particulate (POC and mineral-associated C fractions (MAC of an Oxisol after nine years of maize-oat rotation under NT, with annual applications of PS, soluble fertilizer and combined fertilization (pig slurry + soluble fertilizer. The experiment was initiated in 2001 in Campos Novos, Santa Catarina, with the following treatments: PS at rates of 0 (without fertilization - PS0; 25 (PS25; 50 (PS50; 100 (PS100; and 200 m3 ha-1yr-1 (PS200; fertilization with soluble fertilizer (SF; and mixed fertilization (PS + SF. The TOC content was determined in samples of six soil layers to a depth of 40 cm, and the POC and MAC contents in four layers to a depth of 20 cm. From the rate of 50 m3 ha-1yr-1 and upwards, the soil TOC content and stock increased according to the PS rates in the layers to a depth of 10 cm. The POC and MAC contents and stocks were higher in the surface layers, with a clear predominance of the second fraction, but a greater relative amplitude in the contents of the first fraction.

  10. Influences of Stocking Salmon Carcass Analogs on Salmonids in Klickitat River Tributaries, 2001-2005 Completion Report.

    Energy Technology Data Exchange (ETDEWEB)

    Zendt, Joe; Sharp, Bill (Yakama Nation Fisheries, Toppenish, WA)

    2006-09-01

    This report describes the work completed by the Yakama Nation Fisheries Program (YNFP) in the Klickitat subbasin in south-central Washington under BPA innovative project No.200105500--Influences of stocking salmon carcass analogs on salmonids in Columbia River Tributaries. Salmon carcasses historically provided a significant source of marine-derived nutrients to many stream systems in the Columbia basin, and decreased run sizes have led to a loss of this nutrient source in many streams. Partners in this project developed a pathogen-free carcass analog and stocked the analogs in streams with the following objectives: restoring food availability to streams with reduced anadromous salmon returns; mimicking the natural pathways and timing of food acquisition by salmonids; minimizing unintended negative ecological effects; and increasing the growth and survival of salmonids. In the Klickitat subbasin, carcass analogs were stocked in two streams in 2002 and 2003; a third stream was used as a control. Salmonid fish abundance, growth, and stomach contents were monitored in all three streams before and after carcass analog placement. Fish, invertebrate, and periphyton samples were also collected for stable isotope analysis (to determine if nutrients from carcass analogs were incorporated into the stream food web). Water quality samples were also collected to determine if nutrient overloading occurred in streams. Significant differences in growth were found between fish in treated and untreated stream reaches. Fish in treatment reaches exhibited higher instantaneous growth rates approximately one month after the first carcass analog stocking. Stomach contents sampling indicated that salmonid fish routinely consumed the carcass analog material directly, and that stomach fullness of fish in treatment reaches was higher than in untreated reaches in the first few weeks following carcass analog stockings. No significant differences were detected in fish abundance between

  11. INFLUENCE OF TRIBOSYSTEMS MODIFICATION OF DIESEL SPECIAL POWER-OPERATED ROLLING STOCK ON THEIR INTENSITY OF ABRADING ACTION

    Directory of Open Access Journals (Sweden)

    S. V. Myamlin

    2010-09-01

    Full Text Available It is proved in a theory that the wear intensity of tribosystem of diesels of the special-purpose self-propelled railway rolling stock at laser modification will diminish at growth of concentration of surplus vacancies in superficial layers. Thus there will be the process of crawling over the vacancies and dislocations in the adjacent superficial layers of diesel tribosystems, i.e. running the processes of self-organization. The latter can be achieved at application of discrete laser modification of working surfaces of diesel tribosystems with carbon as a basic element in the form of carbon dioxide or natural graphite with niobium.

  12. Impacts of vinasse and methods of sugarcane harvesting on the availability of K and carbon stock of an Argisol

    Directory of Open Access Journals (Sweden)

    Claudinei Alberto Cardin

    2016-02-01

    Full Text Available ABSTRACT Soils of tropical regions are more weathered and in need of conservation managements to maintain and improve the quality of its components. The objective of this study was to evaluate the availability of K, the organic matter content and the stock of total carbon of an Argisol after vinasse application and manual and mechanized harvesting of burnt and raw sugarcane, in western São Paulo.The data collection was done in the 2012/2013 harvest, in a bioenergy company in Presidente Prudente/SP. The research was arranged out following a split-plot scheme in a 5x5 factorial design, characterized by four management systems: without vinasse application and harvest without burning; with vinasse application and harvest without burning; with vinasse application and harvest after burning; without vinasse application and harvest after burning; plus native forest, and five soil sampling depths (0-10 10-20, 20-30, 30-40, 40-50 cm, with four replications. In each treatment, the K content in the soil and accumulated in the remaining dry biomass in the area, the levels of organic matter, organic carbon and soil carbon stock were determined. The mean values were compared by Tukey test. The vinasse application associated with the harvest without burning increased the K content in soil layers up to 40 cm deep. The managements without vinasse application and manual harvest after burning, and without vinasse application with mechanical harvesting without burning did not increase the levels of organic matter, organic carbon and stock of total soil organic carbon, while the vinasse application and harvest after burning and without burning increased the levels of these attributes in the depth of 0-10 cm.

  13. Ecosystem Carbon Stock Loss after Land Use Change in Subtropical Forests in China

    Directory of Open Access Journals (Sweden)

    Shaohui Fan

    2016-07-01

    Full Text Available Converting secondary natural forests (SFs to Chinese fir plantations (CFPs represents one of the most important (8.9 million ha land use changes in subtropical China. This study estimated both biomass and soil C stocks in a SF and a CFP that was converted from a SF, to quantify the effects of land use change on ecosystem C stock. After the forest conversion, biomass C in the CFP (73 Mg·ha−1 was significantly lower than that of the SF (114 Mg·ha−1. Soil organic C content and stock decreased with increasing soil depth, and the soil C stock in the 0–10 cm layer accounted for more than one third of the total soil C stock over 0–50 cm, emphasizing the importance of management of the top soil to reduce the soil C loss. Total ecosystem C stock of the SF and the CFP was 318 and 200 Mg·ha−1, respectively, 64% of which was soil C for both stands (205 Mg·ha−1 for the SF and 127 Mg·ha−1 for the CFP. This indicates that land use change from the SF to the CFP significantly decreased ecosystem C stock and highlights the importance of managing soil C.

  14. Do stocking rate and a simple run management practice influence the infection of laying hens with gastrointestinal helminths?

    Science.gov (United States)

    Heckendorn, F; Häring, D A; Amsler, Z; Maurer, V

    2009-01-22

    The aim of this experiment conducted at four sites in Switzerland was to investigate the transmission and infectivity of the two main helminth parasite species of poultry (Ascaridia galli and Heterakis gallinarum) in outdoor runs with two different stocking rates. Additionally, the influence of a simple management practice (mowing of run) on helminth transmission was studied. Three run types were created on each site: runs C served as control (stocking rate 10 m(2)/hen, no management), runs B corresponded to runs C but were managed (10 m(2)/hen, management). In runs A stocking rates were doubled compared to control runs (5m(2)/hen, no management). During two subsequent layer flocks, a set of parasitological parameters (faecal egg counts (FECs), prevalence, worm burdens in hens and in tracer animals, helminth eggs in soil) as well as parameters describing the run vegetation were determined. The increased stocking rate (runs A) led to a larger proportion of bare soil and to a reduction of the average vegetation height. In runs with a lower stocking rate (B and C), the proportion of bare soil did not increase during the experimental period. Irrespective of the run type, numbers of helminth eggs in the soil decreased significantly with an increasing distance to the hen houses, while the percentage of ground coverage as well as vegetation height increased. However, across runs the correlation between the percentage of ground cover and the values of eggs per gram soil between runs was very low (r(2)=0.0007, P=0.95) indicating a non-causal relationship. Significant differences in FEC were found in flock 2 (Pgalli and H. gallinarum and repeated mowing of runs did not reduce helminth infections. Lower stocking rates, however, led to a substantial improvement of the run vegetation. PMID:19019546

  15. Temporal-Spatial Variability of Soil Organic Carbon Stocks in a Rehabilitating Ecosystem

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shi-Rong; SUN Bo; ZHAO Qi-Guo; XIAO Peng-Fei; SHU Jian-Ying

    2004-01-01

    In global change research, changes of soil organic carbon (SOC) reservoirs in tropical and subtropical regions are still unknown. The temporal-spatial variability of SOC stocks was determined in a basin of over 579 km2 in subtropical China from 1981 to 2002. ArcGIS8.1 software was utilized for spatial analysis of semivariance, ordinary kriging (OK),and probability kriging (PK). Grid and hierarchical approaches were employed for the sampling scenario in 2002 with 106Global Position System (GPS) established spots sampled. Bulk topsoil samples (0-30 cm) were collected at three random sites on each spot. The SOC content for 1981 came from the SOC map of the Second National Soil Survey. Geostatistical results of the nugget to sill ratio (0.215-0.640) in the rehabilitating ecosystem indicated a moderate spatial dependence for SOC on this large scale. The range of SOC changed from 2.04 km in 1981 to 7.15 km in 2002. The mean topsoil SOC increased by 4.6% from 10.63 g kg-1 (1981) to 11.12 g kg-1 (2002). However, during this 21-year period 25.2%of the total basin area experienced a decrease in SOC. Also, the probability kriging results showed that the geometric mean probabilities of SOC ≤ 6.0 g kg-1, ≤ 11.0 g kg-1 and > 15.0 g kg-1 were 0.188, 0.534 and 0.378, respectively in 2002, comparing to 0.234, 0.416 and 0.234 in that order in 1981, respectively. The SOC storage in the topsoil increased by 17.0% during this time with the main increase occurring in forests and cultivated land, which amounted to 82.5% and 17.0% of the total increase, respectively.

  16. Temporal-Spatial Pattern of Carbon Stocks in Forest Ecosystems in Shaanxi, Northwest China.

    Directory of Open Access Journals (Sweden)

    Gaoyang Cui

    Full Text Available The precise and accurate quantitative evaluation of the temporal and spatial pattern of carbon (C storage in forest ecosystems is critical for understanding the role of forests in the global terrestrial C cycle and is essential for formulating forest management policies to combat climate change. In this study, we examined the C dynamics of forest ecosystems in Shaanxi, northwest China, based on four forest inventories (1989-1993, 1994-1998, 1999-2003, and 2004-2008 and field-sampling measurements (2012. The results indicate that the total C storage of forest ecosystems in Shaanxi increased by approximately 29.3%, from 611.72 Tg in 1993 to 790.75 Tg in 2008, partially as a result of ecological restoration projects. The spatial pattern of C storage in forest ecosystems mainly exhibited a latitude-zonal distribution across the province, increasing from north (high latitude to south (low latitude generally, which signifies the effect of environmental conditions, chiefly water and heat related factors, on forest growth and C sequestration. In addition, different data sources and estimation methods had a significant effect on the results obtained, with the C stocks in 2008 being considerably overestimated (864.55 Tg and slightly underestimated (778.07 Tg when measured using the mean C density method and integrated method, respectively. Overall, our results demonstrated that the forest ecosystem in Shaanxi acted as a C sink over the last few decades. However, further studies should be carried out with a focus on adaption of plants to environmental factors along with forest management for vegetation restoration to maximize the C sequestration potential and to better cope with climate change.

  17. Comparison of carbon-stock changes, eddy-covariance carbon fluxes and model estimates in coastal Douglas-fir stands in British Columbia

    OpenAIRE

    Colin J. Ferster; JA (Tony) Trofymow; Nicholas C Coops; Baozhang Chen; Thomas Andrew Black

    2015-01-01

    Background The global network of eddy-covariance (EC) flux-towers has improved the understanding of the terrestrial carbon (C) cycle, however, the network has a relatively limited spatial extent compared to forest inventory data and plots. Developing methods to use inventory-based and EC flux measurements together with modeling approaches is necessary evaluate forest C dynamics across broad spatial extents. Methods Changes in C stock change (ΔC) were computed based on repeated meas...

  18. Quantifying the sampling error in tree census measurements by volunteers and its effect on carbon stock estimates.

    Science.gov (United States)

    Butt, Nathalie; Slade, Eleanor; Thompson, Jill; Malhi, Yadvinder; Riutta, Terhi

    2013-06-01

    A typical way to quantify aboveground carbon in forests is to measure tree diameters and use species-specific allometric equations to estimate biomass and carbon stocks. Using "citizen scientists" to collect data that are usually time-consuming and labor-intensive can play a valuable role in ecological research. However, data validation, such as establishing the sampling error in volunteer measurements, is a crucial, but little studied, part of utilizing citizen science data. The aims of this study were to (1) evaluate the quality of tree diameter and height measurements carried out by volunteers compared to expert scientists and (2) estimate how sensitive carbon stock estimates are to these measurement sampling errors. Using all diameter data measured with a diameter tape, the volunteer mean sampling error (difference between repeated measurements of the same stem) was 9.9 mm, and the expert sampling error was 1.8 mm. Excluding those sampling errors > 1 cm, the mean sampling errors were 2.3 mm (volunteers) and 1.4 mm (experts) (this excluded 14% [volunteer] and 3% [expert] of the data). The sampling error in diameter measurements had a small effect on the biomass estimates of the plots: a volunteer (expert) diameter sampling error of 2.3 mm (1.4 mm) translated into 1.7% (0.9%) change in the biomass estimates calculated from species-specific allometric equations based upon diameter. Height sampling error had a dependent relationship with tree height. Including height measurements in biomass calculations compounded the sampling error markedly; the impact of volunteer sampling error on biomass estimates was +/- 15%, and the expert range was +/- 9%. Using dendrometer bands, used to measure growth rates, we calculated that the volunteer (vs. expert) sampling error was 0.6 mm (vs. 0.3 mm), which is equivalent to a difference in carbon storage of +/- 0.011 kg C/yr (vs. +/- 0.002 kg C/yr) per stem. Using a citizen science model for monitoring carbon stocks not only has

  19. Rapid carbon turnover beneath shrub and tree vegetation is associated with low soil carbon stocks at a subarctic treeline.

    Science.gov (United States)

    Parker, Thomas C; Subke, Jens-Arne; Wookey, Philip A

    2015-05-01

    Climate warming at high northern latitudes has caused substantial increases in plant productivity of tundra vegetation and an expansion of the range of deciduous shrub species. However significant the increase in carbon (C) contained within above-ground shrub biomass, it is modest in comparison with the amount of C stored in the soil in tundra ecosystems. Here, we use a 'space-for-time' approach to test the hypothesis that a shift from lower-productivity tundra heath to higher-productivity deciduous shrub vegetation in the sub-Arctic may lead to a loss of soil C that out-weighs the increase in above-ground shrub biomass. We further hypothesize that a shift from ericoid to ectomycorrhizal systems coincident with this vegetation change provides a mechanism for the loss of soil C. We sampled soil C stocks, soil surface CO2 flux rates and fungal growth rates along replicated natural transitions from birch forest (Betula pubescens), through deciduous shrub tundra (Betula nana) to tundra heaths (Empetrum nigrum) near Abisko, Swedish Lapland. We demonstrate that organic horizon soil organic C (SOCorg ) is significantly lower at shrub (2.98 ± 0.48 kg m(-2) ) and forest (2.04 ± 0.25 kg m(-2) ) plots than at heath plots (7.03 ± 0.79 kg m(-2) ). Shrub vegetation had the highest respiration rates, suggesting that despite higher rates of C assimilation, C turnover was also very high and less C is sequestered in the ecosystem. Growth rates of fungal hyphae increased across the transition from heath to shrub, suggesting that the action of ectomycorrhizal symbionts in the scavenging of organically bound nutrients is an important pathway by which soil C is made available to microbial degradation. The expansion of deciduous shrubs onto potentially vulnerable arctic soils with large stores of C could therefore represent a significant positive feedback to the climate system. PMID:25367088

  20. Soil carbon and nitrogen stocks in traditional agricultural and agroforestry systems in the semiarid region of Brazil

    Directory of Open Access Journals (Sweden)

    José Augusto Amorim Silva do Sacramento

    2013-06-01

    Full Text Available In the semiarid region of Brazil, inadequate management of cropping systems and low plant biomass production can contribute to reduce soil carbon (C and nitrogen (N stocks; therefore, management systems that preserve C and N must be adopted. This study aimed to evaluate the changes in soil C and N stocks that were promoted by agroforestry (agrosilvopastoral and silvopastoral and traditional agricultural systems (slash-and-burn clearing and cultivation for two and three years and to compare these systems with the natural Caatinga vegetation after 13 years of cultivation. The experiment was carried out on a typical Ortic Chromic Luvisol in the municipality of Sobral, Ceará, Brazil. Soil samples were collected (layers 0-6, 6-12, 12-20, 20-40 and 40-60 cm with four replications. The plain, convex and concave landforms in each study situation were analyzed, and the total organic C, total N and densities of the soil samples were assessed. The silvopastoral system promoted the greatest long-term reductions in C and N stocks, while the agrosilvopastoral system promoted the smallest losses and therefore represents a sustainable alternative for soil C and N sequestration in these semiarid conditions. The traditional agricultural system produced reductions of 58.87 and 9.57 Mg ha-1 in the organic C and total N stocks, respectively, which suggests that this system is inadequate for these semiarid conditions. The organic C stocks were largest in the concave landform in the agrosilvopastoral system and in the plain landform in the silvopastoral system, while the total N values were highest in the concave landform in the native, agrosilvopastoral and silvopastoral systems.

  1. Net Primary Production and Carbon Stocks for Subarctic Mesic-Dry Tundras with Contrasting Microtopography, Altitude, and Dominant Species

    DEFF Research Database (Denmark)

    Campioli, Matteo; Michelsen, Anders; Demey, A; Vermeulen, Annemie; Samson, R; Lemeur, R

    2009-01-01

    production was obtained from average species growth rates, previously assessed at the sites. Results showed that aboveground vascular NPP (15-270 g m-2), annual NPP (214-282 g m-2 or 102-137 g C m-2) and vegetation biomass (330-2450 g m-2) varied greatly among communities. Vegetation dominated by Empetrum...... hermaphroditum is more productive than Cassiope tetragona vegetation. Although the large majority of the apical NPP occurred in early-mid season (85%), production of stems and evergreen leaves proceeded until about 2 weeks before senescence. Most of the vascular vegetation was belowground (80%), whereas most of......Mesic-dry tundras are widespread in the Arctic but detailed assessments of net primary production (NPP) and ecosystem carbon (C) stocks are lacking. We addressed this lack of knowledge by determining the seasonal dynamics of aboveground vascular NPP, annual NPP, and whole-ecosystem C stocks in five...

  2. Chemical attributes, total organic carbon stock and humified fractions of organic matter soil submitted to different systems of sugarcane management

    Directory of Open Access Journals (Sweden)

    Jean Sérgio Rosset

    2014-10-01

    Full Text Available Mechanized harvesting maintenance of trash from cane sugar and soil application of waste as vinasse and filter cake can improve the system of crop yield. Thus, this study aimed to evaluate the changes in the chemical, the stock of total organic carbon and humified organic matter fractions in an Oxisol cultivated with cane sugar with the following management systems: with sugarcane vinasse application (CCV, without application of burnt cane waste (CQS, with burnt cane vinasse application (CQV, with application of burnt cane filter cake (CQTF and burnt cane with joint application of vinasse and filter cake (CQVTF. For reference we used an area of natural vegetation (NV, Cerrado sensu stricto. Treatment CQVTF showed improvement in soil chemical properties, increased inventory levels of total organic carbon – TOC (values ranging from 21.28 to 40.02 Mg ha-1 and humified fractions of soil organic matter in relation to other treatments. The CQS area at a depth of 0-0.05 m, showed the greatest losses of soil TOC stocks (56.3% compared to NV. The adoption of management presented CCV and chemical attributes of the soil TOC stocks equivalent to those observed in areas with CQV CQTF and despite the short period of adoption (3 years. The TOC correlated with the sum of bases (r = 0.76 **, cation exchange capacity (r = 0.59 ** and base saturation (r = 0.63 **, while the humic acids (r = 0.40 ** fulvic acids (r = 0.49 ** and humin (r = 0.59 ** correlated with the cation exchange capacity of the soil. These results indicate that the preservation of trash in the management of cane sugar added to the application of vinasse and filter cake increases the TOC stocks promoting improvement in soil chemical properties.

  3. Kitting versus line stocking in the automotive assembly industry: the influence of part characteristics

    OpenAIRE

    Limère, Veronique; Van Landeghem, Hendrik; Aghezzaf, El-Houssaine

    2011-01-01

    Kitting and line stocking are two part feeding methods that are common in industry. Each system has particular operational benefits and disadvantages but there is a lack of research investigating the trade-offs between both systems. A mathematical cost model is presented for the assignment of individual parts to the materials supply method which is most cost effective for the overall materials delivery system (kitting or line stocking). The model is tested on realistic datasets. Results are p...

  4. ROMANIAN COMPANIES INCREASING PERFORMANCE UNDER THE INFLUENCE OF THEIER CAPITALIZATION STOCK

    OpenAIRE

    Assoc. Prof. Dalia Simion Ph. D, Assoc. Prof. Elena Tob Ph. D, Asist. Sabin Armelu Ph. D Student

    2011-01-01

    These Increasing importance and usefulness of the capital market mechanism functioning market economy of our country was emphasized more than ever lately, because it contributes to the achievement of two major objectives namely: financing economic activity and ensure mobility capital on economic efficiency principles. Using the stock market as a form of mobilization of capital resources and financing activities of a company, is a common practice in mature stock markets, many of these developi...

  5. Is it true that Indian gold price influenced by Indian stock market reaction?

    OpenAIRE

    Somnath Mukhuti; Amalendu Bhunia

    2013-01-01

    The present study investigates the reaction of Indian stock market index (Sensex and Nifty) on Indian gold price or the relationship between Indian gold price and Indian stock market index (Sensex and Nifty) for the period of study between 2nd January 1991 and 10th August 2012 using daily time series data with the application of bivariate and multivariate cointegration test. In times of national crisis, bank failures, rupee depreciation, and in case of negative real interest rate, people cons...

  6. Estimating Carbon STOCK Changes of Mangrove Forests Using Satellite Imagery and Airborne LiDAR Data in the South Sumatra State, Indonesia

    Science.gov (United States)

    Maeda, Y.; Fukushima, A.; Imai, Y.; Tanahashi, Y.; Nakama, E.; Ohta, S.; Kawazoe, K.; Akune, N.

    2016-06-01

    The purposes of this study were 1) to estimate the biomass in the mangrove forests using satellite imagery and airborne LiDAR data, and 2) to estimate the amount of carbon stock changes using biomass estimated. The study area is located in the coastal area of the South Sumatra state, Indonesia. This area is approximately 66,500 ha with mostly flat land features. In this study, the following procedures were carried out: (1) Classification of types of tree species using Satellite imagery in the study area, (2) Development of correlation equations between spatial volume based on LiDAR data and biomass stock based on field survey for each types of tree species, and estimation of total biomass stock and carbon stock using the equation, and (3) Estimation of carbon stock change using Chronological Satellite Imageries. The result showed the biomass and the amount of carbon stock changes can be estimated with high accuracy, by combining the spatial volume based on airborne LiDAR data with the tree species classification based on satellite imagery. Quantitative biomass monitoring is in demand for projects related to REDD+ in developing countries, and this study showed that combining airborne LiDAR data with satellite imagery is one of the effective methods of monitoring for REDD+ projects.

  7. Simulating carbon stocks and fluxes of an African tropical montane forest with an individual-based forest model.

    Directory of Open Access Journals (Sweden)

    Rico Fischer

    Full Text Available Tropical forests are carbon-dense and highly productive ecosystems. Consequently, they play an important role in the global carbon cycle. In the present study we used an individual-based forest model (FORMIND to analyze the carbon balances of a tropical forest. The main processes of this model are tree growth, mortality, regeneration, and competition. Model parameters were calibrated using forest inventory data from a tropical forest at Mt. Kilimanjaro. The simulation results showed that the model successfully reproduces important characteristics of tropical forests (aboveground biomass, stem size distribution and leaf area index. The estimated aboveground biomass (385 t/ha is comparable to biomass values in the Amazon and other tropical forests in Africa. The simulated forest reveals a gross primary production of 24 tcha(-1 yr(-1. Modeling above- and belowground carbon stocks, we analyzed the carbon balance of the investigated tropical forest. The simulated carbon balance of this old-growth forest is zero on average. This study provides an example of how forest models can be used in combination with forest inventory data to investigate forest structure and local carbon balances.

  8. Simulating Carbon Stocks and Fluxes of an African Tropical Montane Forest with an Individual-Based Forest Model

    Science.gov (United States)

    Fischer, Rico; Ensslin, Andreas; Rutten, Gemma; Fischer, Markus; Schellenberger Costa, David; Kleyer, Michael; Hemp, Andreas; Paulick, Sebastian; Huth, Andreas

    2015-01-01

    Tropical forests are carbon-dense and highly productive ecosystems. Consequently, they play an important role in the global carbon cycle. In the present study we used an individual-based forest model (FORMIND) to analyze the carbon balances of a tropical forest. The main processes of this model are tree growth, mortality, regeneration, and competition. Model parameters were calibrated using forest inventory data from a tropical forest at Mt. Kilimanjaro. The simulation results showed that the model successfully reproduces important characteristics of tropical forests (aboveground biomass, stem size distribution and leaf area index). The estimated aboveground biomass (385 t/ha) is comparable to biomass values in the Amazon and other tropical forests in Africa. The simulated forest reveals a gross primary production of 24 tcha-1yr-1. Modeling above- and belowground carbon stocks, we analyzed the carbon balance of the investigated tropical forest. The simulated carbon balance of this old-growth forest is zero on average. This study provides an example of how forest models can be used in combination with forest inventory data to investigate forest structure and local carbon balances. PMID:25915854

  9. Improving the ISBACC land surface model simulation of water and carbon fluxes and stocks over the Amazon forest

    Science.gov (United States)

    Joetzjer, E.; Delire, C.; Douville, H.; Ciais, P.; Decharme, B.; Carrer, D.; Verbeeck, H.; De Weirdt, M.; Bonal, D.

    2015-06-01

    We evaluate the ISBACC (Interaction Soil Biosphere Atmosphere Carbon Cycle) land surface model (LSM) over the Amazon forest, and propose a revised parameterization of photosynthesis, including new soil water stress and autotrophic respiration (RA) functions. The revised version allows the model to better capture the energy, water and carbon fluxes when compared to five Amazonian flux towers. The performance of ISBACC is slightly site dependent although similar to the widely evaluated LSM ORCHIDEE (Organizing Carbon and Hydrology In Dynamic Ecosystems - version 1187), which is based on different assumptions. Changes made to the autotrophic respiration functions, including a vertical profile of leaf respiration, lead to yearly simulated carbon use efficiency (CUE) and carbon stocks which is consistent with an ecophysiological meta-analysis conducted on three Amazonian sites. Despite these major improvements, ISBACC struggles to capture the apparent seasonality of the carbon fluxes derived from the flux tower estimations. However, there is still no consensus on the seasonality of carbon fluxes over the Amazon, stressing a need for more observations as well as a better understanding of the main drivers of autotrophic respiration.

  10. Soil Organic and Inorganic Carbon Stocks in Yanqi Basin of Northwestern China: A Study of Land Use Impact

    Science.gov (United States)

    Wang, J.; Wang, X.; Zhang, J.

    2011-12-01

    Soil carbon storage is an important element in the global carbon budgets. Although soil organic carbon (SOC) is low on arid land, there is evidence of a large amount of soil inorganic carbon (SIC). Here, we present a study of soil carbon dynamics, which was carried out in the central Xinjiang, i.e., the Yanqi Basin. The objective of this study is to examine the effect of land use on both SOC and SIC. We sampled 20 profiles to 100 cm depth, which are covered with little vegetation (i.e., desert land), shrub, crop and grass. We used three methods to measure SOC and SIC contents. Soil organic C content are determined using the automated CNS analyzer, the traditional Walkleyand Black method and Loss-on-ignition at 375°C for 17 hours, and soil inorganic C content by the automated CNS analyzer, pressure calimeter method and Loss-on-ignition from 375°C to 800°C. There are high correlations in both SOC and SIC among all three methods (Figure 1). Our results show that both SOC and SIC follow an order: desert land 10 kg m-2, to >50 kg m-2, respectively, for the 0-100 cm profile. On average, SIC counts >75% of the total soil carbon stock across all the land use types (Figure 2). Our study suggests that agricultural development on desert and shrub land is likely to increase soil organic/inorganic carbon storage.

  11. Unravelling the influence of soil erosion on the within-field vertical heterogeneity of SOC stock and stability

    Science.gov (United States)

    Meersmans, Jeroen; Quine, Tim; Hartley, Iain

    2014-05-01

    Intensified agro-management since the green revolution (from halfway the 20th century) significantly increased soil erosion and its associated lateral fluxes of soil properties within agricultural catchments. During this relatively short period of time considerably large amounts of fertile topsoil have been removed from erosional sites and have accumulated in depositional zones. As a consequence, the associated three dimensional spatial distribution of SOC has been modified significantly, especially within croplands under conventional tillage. As on the one hand erosion affects the stability of soil organic matter (i.e. breakdown of soil aggregates during transport process) and on the other hand organic carbon in depositional zones is assumed to be stored in stable environments, the increased within-field differences in SOC probably cause a major change in regional SOC dynamics. Nevertheless, the variability of SOC at smaller scales in complex terrain driven by soil erosion, such as stable subsoil carbon buried in depositional areas, is still rather understudied and is not (well) represented in current regional C estimates. In the present study we aim to unravel the variation in quantity and quality of SOC depth distributions along typical hillslope transects under cropland (Devon, UK) and to relate these to soil redistribution rates and variations in C input, i.e. below and above ground biomass productivity. The radionuclide isotope Caesium-137 (137Cs) was used as proxy for soil erosion. SOC stability has been studied in a depth specific context by running long-term incubation experiments. Moreover, the effect of potential increased C input has been tested by applying different rates of glucose additions on some of the incubated soil samples. The results show contrasting vertical patterns in SOC stock and stability depending on the rate and type of erosion. For example, sites characterized by deposition due to water erosion (i.e. footslope) have much higher SOC

  12. Assessing land-use and carbon stock in slash-and-burn ecosystems in tropical mountain of Laos based on time-series satellite images

    Science.gov (United States)

    Inoue, Yoshio; Kiyono, Yoshiyuki; Asai, Hidetoshi; Ochiai, Yukihito; Qi, Jiaguo; Olioso, Albert; Shiraiwa, Tatsuhiko; Horie, Takeshi; Saito, Kazuki; Dounagsavanh, Linkham

    2010-08-01

    In the tropical mountains of Southeast Asia, slash-and-burn (S/B) agriculture is a widely practiced and important food production system. The ecosystem carbon stock in this land-use is linked not only to the carbon exchange with the atmosphere but also with food and resource security. The objective of this study was to provide quantitative information on the land-use and ecosystem carbon stock in the region as well as to infer the impacts of alternative land-use and ecosystem management scenarios on the carbon sequestration potential at a regional scale. The study area was selected in a typical slash-and-burn region in the northern part of Laos. The chrono-sequential changes of land-use such as the relative areas of community age and cropping (C) + fallow (F) patterns were derived from the analysis of time-series satellite images. The chrono-sequential analysis showed that a consistent increase of S/B area during the past three decades and a rapid increase after 1990. Approximately 37% of the whole area was with the community age of 1-5 years, whereas 10% for 6-10 years in 2004. The ecosystem carbon stock at a regional scale was estimated by synthesizing the land-use patterns and semi-empirical carbon stock model derived from in situ measurements where the community age was used as a clue to the linkage. The ecosystem carbon stock in the region was strongly affected by the land-use patterns; the temporal average of carbon stock in 1C + 10F cycles, for example, was greater by 33 MgC ha -1 compared to that in 1C + 2F land-use pattern. The amount of carbon lost from the regional ecosystems during 1990-2004 periods was estimated to be 42 MgC ha -1. The study approach proved to be useful especially in such regions with low data-availability and accessibility. This study revealed the dynamic change of land-use and ecosystem carbon stock in the tropical mountain of Laos as affected by land-use. Results suggest the significant potential of carbon sequestration through

  13. Assessing land-use and carbon stock in slash-and-burn ecosystems in tropical mountain of Laos based on time-series satellite images

    OpenAIRE

    Inoue, Yoshio; Kiyono, Yoshiyuki; Asai, Hidetoshi; Ochiai, Yukihito; Qi, Jiaguo; Olioso, Albert; Shiraiwa, Tatsuhiko; HORIE,TAKESHI; Saito, Kazuki; Dounagsavanh, Linkham

    2010-01-01

    In the tropical mountains of Southeast Asia, slash-and-burn (S/B) agriculture is a widely practiced and important food production system. The ecosystem carbon stock in this land-use is linked not only to the carbon exchange with the atmosphere but also with food and resource security. The objective of this study was to provide quantitative information on the land-use and ecosystem carbon stock in the region as well as to infer the impacts of alternative land-use and ecosystem management scen...

  14. Ecosystem Disturbance Effects on Land Surface Temperature, Forest Carbon Stocks, and Primary Productivity in the Western United States

    Science.gov (United States)

    Cooper, L. A.; Ballantyne, A.; Holden, Z. A.; Landguth, E.

    2015-12-01

    Disturbance plays an important role in the structure, composition, and nutrient cycling of forest ecosystems. Climate change is resulting in an increase in disturbance frequency and intensity, making it critical that we quantify the physical and chemical impacts of disturbances on forests. The impacts of disturbance are thought to vary widely depending on disturbance type, location, and climate. More specifically, fires, insect infestations, and other types of disturbances differ in their timing, extent, and intensity making it difficult to assess the true impact of disturbances on local energy budgets and carbon cycling. Here, we provide a regional analysis of the impacts of fire, insect attack, and other disturbances on land surface temperature (LST), carbon stocks, and gross primary productivity (GPP). Using disturbances detected with MODIS Enhanced Vegetation Index (EVI) time series between 2002 and 2012, we find that the impacts of disturbance on LST, carbon stocks, and GPP vary widely according to local climate, vegetation, and disturbance type and intensity. Fires resulted in the most distinct impacts on all response variables. Forest responses to insect epidemics were more varied in their magnitude and timing. The results of this study provide an important estimation of the variability of climate and ecosystem responses to disturbance across a large and heterogeneous landscape. With disturbance projected to increase in both frequency and intensity around the globe in the coming years, this information is vitally important to effectively manage forests into the future.

  15. Evaluating Public Plantation and Community Planted Forests under the CDM and REDD+ Mechanism for Carbon Stock in Nepal

    Directory of Open Access Journals (Sweden)

    Ram Asheshwar MANDAL

    2013-09-01

    Full Text Available Public plantations (PPs and Community planted forests (CPFs are inimitable types of participatory forest management practices in Nepal, but their eligibility issues under the framework of clean development mechanism (CDM and reducing emission from the deforestation and forest degradation mechanism (REDD+ are not evaluated. So, to explore the management system of PP and CPF, we compared forest carbon stocks in plantations and evaluated these plantations under these mechanisms as objectives of this research. The relevant documents were revised and altogether 55 samples were collected from Shreepur, Banauta and Bisbity PPs and Sita, Ramnagar and Jogikuti CPFs, in Mahottary district, Nepal. The equation of Chave et al was used to calculate the biomass, which was further converted into carbon. Meanwhile, management practices were evaluated under the framework of CDM and REDD+. The PPs are public land managed, especially by disadvantaged communities, while CPFs are the patches of national forest managed by users. The variation in carbon stock was found to be highest (148.89 ton ha-1 in Sita CPF and lowest (30.34 ton ha-1 in Bisbitty PP. In fact, it is difficult to certify plantations under CDM, due to its complexity, but they can easily be candidate to the REDD+ mechanism, if they are bundled with large forest blocks.

  16. Impacts of Land Use Change, Nitrogen Deposition and Nitrogen Fertilizers on Carbon and Nitrogen Stocks of Plants and Soils

    Science.gov (United States)

    Jain, A. K.; Yang, X.; Liang, M.; Barman, R.; Meiyappan, P.

    2010-12-01

    Changes in Earth’s vegetation cover have a potential to alter regional and global climate through changes in the biophysical and biogeochemical characteristics of the Earth’s surface. Historically, land-use change (LUC) activities have generally released carbon (C) to the atmosphere through the conversion of forests to croplands and pastures, but in recent decades C stocks in forest ecosystems have increased through reforestation, afforestation and forest regrowth on abandoned land. The accumulation of C stocks can be constrained if the LUCs occur in nitrogen (N) limited regions. However, soil N supply through N fertilizer application and N deposition could reduce, or even remove the N limitation on C uptake. These additional sources of N in soils are a major source of nitrous oxide (N2O) through nitrification and denitrification processes. Therefore, the terrestrial ecosystem responses to LUCs have a potential to change the concentrations of CO2 and N2O, two important greenhouse gases, and climate. In this study, an existing terrestrial coupled C-N cycle model, the Integrated Science Assessment Model (ISAM), is used to examine the response of terrestrial C and N stocks to historical LUC and the interactions with atmospheric CO2, climate, N deposition and N fertilizer. The ISAM biogeochemical cycles consist of fully prognostic C and N dynamics associated with changes in LUCs, vegetation, litter decomposition, and soil organic matter. The ISAM biophysical model accounts for water and energy processes in the vegetation and soil column. By quantifying the spatial distribution of C and N sources and sinks, this study will help us more accurately determine how much carbon is being stored or released. This is particularly important in the context of the Kyoto protocol, which allows a country to apply the carbon stored in its forests and other ecosystems toward its budgeted reduction in CO2 and other greenhouse gases.

  17. Carbon and biomass stocks in a fragment of cerradão in Minas Gerais state, Brazil

    OpenAIRE

    Vinícius Augusto Morais; José Roberto Soares Scolforo; Carlos Alberto Silva; José Marcio de Mello; Lucas Rezende Gomide; Antônio Donizette de Oliveira

    2013-01-01

    This study aimed at quantifying carbon (C) and biomass stocks in shoot portion, leaf litter, roots and soil within a fragment of dense savanna 'cerradão', 158.5 ha in area, located in Minas Gerais state. Measures were quantified using dendrometric parameters obtained during the forest inventory and collection of leaf litter, root and soil samples. Furrows were dug in the soil each 100 cm long, 50 cm wide and 100 cm deep in order to collect root samples at depths of 0-30 cm, 30-50 cm and 50-10...

  18. Seasonal variability in biological carbon biomass standing stocks and production in the surface layers of the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaiah, N.; Fernandes, V.; Paul, J.T.; Jyothibabu, R.; Gauns, M.; Jayraj, E.A.

    of Marine Sciences Vol. 39(3), September 2010, pp. 369-379 Seasonal variability in biological carbon biomass standing stocks and production in the surface layers of the Bay of Bengal N Ramaiah1*, V Fernandes1, J T Paul1, R Jyothibabu2, G... Mangesh1& E A Jayraj2 1National Institute of Oceanography, Dona Paula, Goa 403004, India 2Regional Centre of NIO, Kochi 682 018. India [Email: ramaiah@nio.org] Received 9 June 2010; revised 13 October 2010 As a part of the Bay of Bengal Process Study...

  19. Phosphorus fertilisation under nitrogen limitation can deplete soil carbon stocks - evidence from Swedish meta-replicated long-term field experiments

    Science.gov (United States)

    Poeplau, C.; Bolinder, M. A.; Kirchmann, H.; Kätterer, T.

    2015-10-01

    Increasing soil organic carbon (SOC) in agricultural soils can mitigate atmospheric CO2 concentration and also contribute to increase soil fertility and ecosystem resilience. The role of major nutrients on SOC dynamics is complex, due to simultaneous effects on net primary productivity (NPP) that influence crop residue carbon inputs and on the rate of heterotrophic respiration (carbon outputs). This study investigated the effect on SOC stocks of three different levels of phosphorus and potassium (PK) fertilisation rates in the absence of nitrogen fertilisation and of three different levels of nitrogen in the absence of PK. This was done by analysing data from 10 meta-replicated Swedish long-term field experiments (> 45 years). With N fertilisation, SOC stocks followed yield increases. However, for all PK levels, we found average SOC losses ranging from -0.04 ± 0.09 Mg ha-1 yr-1 (ns) for the lowest to -0.09 ± 0.07 Mg ha-1 yr-1 (p = 0.008) for the highest application rate, while crop yields as a proxy for carbon input increased significantly with PK fertilization by 1, 10 and 15 %. We conclude that SOC dynamics are mainly output-driven in the PK fertilised regime but mostly input-driven in the N fertilised regime, due to the much more pronounced response of NPP to N than to PK fertilisation. It has been established that P rather than K is the element affecting ecosystem carbon fluxes, where P fertilisation has been shown to: (i) stimulate heterotrophic respiration, (ii) reduce the abundance of arbuscular mycorrhizal fungi and (iii) decrease crop root : shoot ratio, leading to lower root-derived carbon input. The higher export of N in the PK fertilised plots in this study could (iv) have led to increased N mining and thus mineralisation of organic matter. More integrated experiments are needed to gain a better understanding of the relative importance of each of the above-mentioned mechanisms leading to SOC losses after P addition.

  20. Phosphorus fertilisation under nitrogen limitation can deplete soil carbon stocks: evidence from Swedish meta-replicated long-term field experiments

    Science.gov (United States)

    Poeplau, Christopher; Bolinder, Martin A.; Kirchmann, Holger; Kätterer, Thomas

    2016-02-01

    Increasing soil organic carbon (SOC) in agricultural soils can mitigate atmospheric CO2 concentration and also contribute to increased soil fertility and ecosystem resilience. The role of major nutrients in SOC dynamics is complex, due to simultaneous effects on net primary productivity (NPP) that influence crop residue carbon inputs and in the rate of heterotrophic respiration (carbon outputs). This study investigated the effect on SOC stocks of three different levels of phosphorus and potassium (PK) fertilisation rates in the absence of nitrogen fertilisation and of three different levels of nitrogen fertiliser in the absence of PK fertiliser. This was done by analysing data from 10 meta-replicated Swedish long-term field experiments (> 45 years). With N fertilisation, SOC stocks followed yield increases. However, for all PK levels, we found average SOC losses ranging from -0.04 ± 0.09 Mg ha-1 yr-1 (ns) for the lowest to -0.09 ± 0.07 Mg ha-1 yr-1 (p = 0.008) for the highest application rate, while crop yields as a proxy for carbon input increased significantly with PK fertilisation by 1, 10 and 15 %. We conclude that SOC dynamics are mainly output-driven in the PK-fertilised regime but mostly input-driven in the N-fertilised regime, due to the much more pronounced response of NPP to N than to PK fertilisation. It has been established that P rather than K is the element affecting ecosystem carbon fluxes, where P fertilisation has been shown to (i) stimulate heterotrophic respiration, (ii) reduce the abundance of arbuscular mycorrhizal fungi and (iii) decrease the crop root : shoot ratio, leading to higher root-derived carbon input. The higher export of N in the PK-fertilised plots in this study could (iv) have led to increased N mining and thus mineralisation of organic matter. More integrated experiments are needed to gain a better understanding of the relative importance of each of the above-mentioned mechanisms leading to SOC losses after P addition.

  1. Organic carbon stocks in permafrost-affected soils from Admiralty Bay, Antarctica

    Science.gov (United States)

    Simas, F.N.B.; Schaefer, C.E.G.R.; Mendonça, E.S.; Silva, I.R.; Santana, R.M.; Ribeiro, A.S.S.

    2007-01-01

    Recent works show that organic matter accumulation in some soils from coastal Antarctica is higher than previously expected. The objective of the present work was to estimate the organic C stocks for soils from maritime Antarctica. Cryosols from subpolar desert landscapes presented the lowest organic C stocks. Ornithogenic soils are the most important C reservoirs in terrestrial ecosystems in this part of Antarctica. Although these soils correspond to only 2.5 % of the ice-free areas at Admiralty Bay, they contain approximately 20 % of the estimated C stock. Most of the organic C in the studied soils is stored in the active layer but in some cases the C is also stored in the permafrost.

  2. Is Tree Species Diversity or Species Identity the More Important Driver of Soil Carbon Stocks, C/N Ratio, and pH?

    DEFF Research Database (Denmark)

    Dawud, Seid Muhie; Raulund-Rasmussen, Karsten; Domisch, Timo;

    2016-01-01

    stocks and C/N ratios in the 20–40 cm layer, whereas identity in terms of conifer proportion increased C stocks and C/N ratios only in forest floors. A positive relationship between C stocks and root biomass in the 30–40 cm layer suggested that belowground niche complementarity could be a driving...... mechanism for higher root carbon input and in turn a deeper distribution of C in diverse forests. Diversity and identity affected soil pH in topsoil with positive and negative impacts, respectively. More diverse forests would lead to higher soil nutrient status as reflected by higher topsoil pH, but there...

  3. Stocks and sources of carbon buried in the salt marshes and seagrass beds of Patos Lagoon Estuary, Southern Brazil

    Science.gov (United States)

    Patterson, Elizabeth; Johnson, Beverly; Dostie, Philip; Copertino, Margareth

    2016-04-01

    This project investigates carbon stocks in salt marshes and seagrass beds in the Patos Lagoon estuary, the largest choked lagoon in the world, located in Southern Brazil. The study was conducted in the mesohaline region, at three shallow shoals. At each shoal, three sediment cores (50 cm deep) and plant biomass samples (above and belowground) were collected along a transect line, spanning from the marsh to seagrass beds (total = 9 sediment cores). The 50cm cores were subsampled and analyzed for organic carbon (C) and nitrogen (N) content, C/N ratios, and the isotope ratios of 13C/12C, and 15N/14N. The organic carbon content of these sediments ranged between 10% (in surface sediments) and 1% (deeper in the core), suggesting that both the salt marshes and seagrass beds in this region are sequestering carbon. Early results indicate that cores taken in marsh dominated by C3 plants (Scirpus maritimus) tended to be the most depleted in 13C with δ13C values around -25‰. Cores taken in marsh dominated by C4 plants (Spartina alterniflora, Spartina densiflora), seagrass beds (Ruppia maritima) , and non vegetated areas were generally isotopically heavier with δ13C values ranging -20‰ to -15‰, indicating a mix of organic sources in the sediments. The δ15N values and C/N ratios both varied with most values falling in a range of 2-8‰ and 7-20 respectively. Analysis of the δ 34S isotope composition of the sediments is currently underway and may provide better information on the relative contributions of macro and micro algae in the sediments. The present data will reveal the carbon stock size, as well as the types and history of organic matter deposition in Patos Lagoon estuary.

  4. How QFII Influence Chinese Stock Market Liberalization? Compare with Taiwan's Experience

    OpenAIRE

    Chan, Oi Yee, Iris

    2008-01-01

    QFII (Qualified Foreign Institutional Investors) announced in November, 2002 and formally implemented in 1st of December, 2002. It is the initial stock market liberalization policy adopted by Chinese authorizes after the accession of WTO. Stock market liberalization is a decision to allow foreign investors to purchase domestic share. In this dissertation, the major improvements on Chinese QFIIÃ�Â�Ã�¢Ã�Â�Ã�Â�Ã�Â�Ã�Â�s entry criteria and investment quota are recommended from the TaiwanÃ�Â...

  5. Land use and land management effects on soil organic carbon stock in Mediterranean agricultural areas (Southern Spain)

    Science.gov (United States)

    Parras-Alcántara, Luis; Lozano-García, Beatriz

    2014-05-01

    INTRODUCTION Soils play a key role in the carbon geochemical cycle. Agriculture contributes to carbon sequestration through photosynthesis and the incorporation of carbon into carbohydrates. Soil management is one of the best tools for climate change mitigation. Small increases or decreases in soil carbon content due to changes in land use or management practices, may result in a significant net exchange of carbon between the soil carbon pool and the atmosphere. In the last decades arable crops (AC) have been transformed into olive grove cultivations (OG) or vineyards (V) in Mediterranean areas. A field study was conducted to determine long-term effects of land use change (LUC) (AC by OG and V) on soil organic carbon (SOC), total nitrogen (TN), C:N ratio and their stratification in Calcic-Chromic Luvisols (LVcc/cr) in Mediterranean conditions. MATERIAL AND METHODS An unirrigated farm in Montilla-Moriles (Córdoba, Spain) cultivated under conventional tillage (animal power with lightweight reversible plows and non-mineral fertilization or pesticides) was selected for study in 1965. In 1966, the farm was divided into three plots with three different uses (AC, OG and V). The preliminary analyses were realized in 1965 for AC (AC1), and the second analyses were realized in 2011 for AC (AC2 - winter crop rotation with annual wheat and barley, receiving mineral fertilization or pesticides), OG (annual passes with disk harrow and cultivator in the spring, followed by a tine harrow in the summer receiving mineral fertilization and weed control with residual herbicides), and V (with three or five chisel passes a year from early spring to early autumn with mineral fertilization or pesticides.). In all cases (AC1, AC2, OG and V) were collected soil entire profiles. Soil properties determined were: soil particle size, bulk density, SOC, TN, C:N ratio, stocks and SRs. The statistical significance of the differences in the variables between land use practices was tested using the

  6. Estimating Carbon Stocks Along Depressional Wetlands Using Ground Penetrating Radar (GPR) in the Disney Wilderness Preserve (Orlando, Florida)

    Science.gov (United States)

    McClellan, M. D.; Comas, X.; Wright, W. J.; Mount, G. J.

    2014-12-01

    Peat soils store a large fraction of the global carbon (C) in soil. It is estimated that 95% of carbon in peatlands is stored in the peat soil, while less than 5% occurs in the vegetation. The majority of studies related to C stocks in peatlands have taken place in northern latitudes leaving the tropical and subtropical latitudes clearly understudied. In this study we use a combination of indirect non-invasive geophysical methods (mainly ground penetrating radar, GPR) as well as direct measurements (direct coring) to calculate total C stocks within subtropical depressional wetlands in the Disney Wilderness Preserve (DWP, Orlando, FL). A set of three-dimensional (3D) GPR surveys were used to detect variability of the peat layer thickness and the underlying peat-sand mix layer across several depressional wetlands. Direct samples collected at selected locations were used to confirm depth of each interface and to estimate C content in the laboratory. Layer thickness estimated from GPR and direct C content were used to estimate total peat volume and C content for the entire depressional wetland. Through the use of aerial photos a relationship between surface area along the depressional wetlands and total peat thickness (and thus C content) was established for the depressions surveyed and applied throughout the entire preserve. This work shows the importance of depressional wetlands as critical contributors of the C budget at the DWP.

  7. Carbon stocks quantification in agricultural systems employing succession and rotation of crops in Rio Grande do Sul State, Brazil.

    Science.gov (United States)

    Walter, Michele K. C.; Marinho, Mara de A.; Denardin, José E.; Zullo, Jurandir, Jr.; Paz-González, Antonio

    2013-04-01

    Soil and vegetation constitute respectively the third and the fourth terrestrial reservoirs of Carbon (C) on Earth. C sequestration in these reservoirs includes the capture of the CO2 from the atmosphere by photosynthesis and its storage as organic C. Consequently, changes in land use and agricultural practices affect directly the emissions of the greenhouse gases and the C sequestration. Several studies have already demonstrated that conservation agriculture, and particularly zero tillage (ZT), has a positive effect on soil C sequestration. The Brazilian federal program ABC (Agriculture of Low Carbon Emission) was conceived to promote agricultural production with environmental protection and represents an instrument to achieve voluntary targets to mitigate emissions or NAMAS (National Appropriated Mitigation Actions). With financial resources of about US 1.0 billion until 2020 the ABC Program has a target of expand ZT in 8 million hectares of land, with reduction of 16 to 20 million of CO2eq. Our objective was to quantify the C stocks in soil, plants and litter of representative grain crops systems under ZT in Rio Grande do Sul State, Brazil. Two treatments of a long term experimental essay (> 20 years) were evaluated: 1) Crop succession with wheat (Triticum aestivum L.)/soybean (Glycine max (L.) Merril); 2) Crop rotation with wheat/soybean (1st year), vetch (Vicia sativa L.)/soybean (2nd year), and white oat (Avena sativa L.)/sorghum (Sorghum bicolor L.) (3rd year). C quantification in plants and in litter was performed using the direct method of biomass quantification. The soil type evaluated was a Humic Rhodic Hapludox, and C quantification was executed employing the method referred by "C mass by unit area". Results showed that soybean plants under crop succession presented greater C stock (4.31MgC ha-1) comparing with soybean plants cultivated under crop rotation (3.59 MgC ha-1). For wheat, however, greater C stock was quantified in plants under rotation

  8. Influence of soil C stocks and interannual climatic variability on the CO2 and CH4 exchange of maize cultivated on mineral and organic soils in NE Germany

    Science.gov (United States)

    Pohl, Madlen; Hagemann, Ulrike; Hoffmann, Mathias; Giebels, Michael; Albiac-Borraz, Elisa; Sommer, Michael; Augustin, Jürgen

    2014-05-01

    Due to its glacially influenced genesis and land use history, the soils of the Great Plain Region of NE-Germany show large differences in groundwater levels and soil carbon (C) stocks over short distances. Although generally featuring a rather dry climate, trace gas exchange at individual sites may be influenced by i) interannual climatic variability, particularly with respect to precipitation; as well as by ii) variability of soil C stocks. However, it is still unclear how these factors affect fluxes of CO2 and CH4, and if there is any positive or negative feedback on the C source or sink function of different soil types. We present measured and modeled CO2 and CH4 fluxes of minerally fertilized grain maize for three sites located near Paulinenaue, within the so-called Rhin-Havelluch, a shallow and drained paludification mire complex in NE Germany. The sites are characterized by a distinct gradient of 0-1 m soil organic C stocks: i) Arenosol (AR: mineral soil/distant groundwater; 8 000 g C m-2), ii) Gleysol (GL: organic soil/groundwater-dependent; 35 000 g C m-2), and iii) Histosol (HS: organic soil/near groundwater; 45 000 g C m-2). CO2 flux measurements of ecosystem respiration (Reco), net ecosystem exchange (NEE) and gross primary production (GPP; calculated as difference between NEE and Reco) were conducted every four weeks using a flow-through non-steady-state closed chamber system. Measurement gaps of Reco and NEE were filled by using temperature or radiation-based models, respectively. CH4 fluxes were measured bi-weekly using a static closed chamber system with interval sampling, with gap filling via linear interpolation. Cumulated fluxes of CO2-C (Reco, GPP, NEE) and CH4-C were calculated for a period of four consecutive years (2007-2010). The intensity of CO2-C fluxes increased with growing soil organic C stocks (AR < GL < HS). Mean annual values of the years 2008-2010 for Reco ranged between 1 500 g C m-2 and 2 000 g C m-2; annual GPP fluxes ranged from

  9. The influence of stocking density on the growth of common carp, Cyprinus carpio, in a recirculating aquaculture system

    Directory of Open Access Journals (Sweden)

    Ionica Enache

    2011-04-01

    Full Text Available The paper presents some aspects regarding the influence of stocking density on the breeding of the common carp in a recirculating aquaculture system (RAS. The experiment covered a 30 dayperiod. It was conducted in four aquaculture tanks, 500 L/tank, in the recirculating aquaculture pilot system of “Dunarea de Jos” University of Galați. Two kind of stocking density variants were compared: 64 kg/m3 in V1 (B1, B3 and 32 kg/m3 in V2 (B2, B4. The stocking density was: 491 fish in B1, average weight - 65 g/ fish; 245 fish in B2, average weight - 66 g/ fish; 211 fish in B3, average weight - 152 g/fish; 107 fish in B4, average weight - 150 g/fish. The technological indicators obtained revealed the following: the specific growth rate (SGR, calculated as a mean value on the two repetitions, was 1.28%/day in V1 and 1.49 %/day in V2, indicating better growth in V2; the food conversion ratio (FCR, calculated as the mean value of the two repetitions, was 1.28 in V1 and 1.06 in V2, expressing a higher efficiency in capitalization of food in V2. The mean biomass gain in V1 was 30.46 kg/m3 as compared to 18.55 kg/m3 in V2, almost perfectly correlated with the stocking density. The daily growth rate (DGR varied in a similar way, from 494.57 to 520.90 g/day in V1 and 302.4 to 315.9 g/day in V2. The experiment demonstrated a remarkable technological plasticity in both experimental variants, whereas, in terms of technological performance indicators, it was found that the application of lower stocking densities lead to higher crop biomass. The high stocking density means, therefore, large amounts of metabolic waste, removed from the breeding units through their effluent, the recirculating flow of which is 4m3/h, enough to ensure the whole volume of water in a growth tank to be changed every half hour.

  10. Microbially influenced corrosion of carbon steels

    Energy Technology Data Exchange (ETDEWEB)

    White, D.C.; Jack, R.F.; Dowling, N.J.E.; Franklin, M.J.; Nivens, D.E.; Brooks, S.; Mittelman, M.W.; Vass, A.A. (Tennessee Univ., Knoxville, TN (USA). Inst. for Applied Microbiology); Isaacs, H.S. (Brookhaven National Lab., Upton, NY (USA))

    1990-01-01

    Microbially influenced corrosion of pipeline steels is an economically important problem. Microbes form tubercles which block fluid flow and can facilitate localized corrosion leading to through-wall penetrations. Microbes of diverse physiological types and metabolic potentialities have been recovered from fresh tubercles or under-deposit corrosion and have been characterized. In tests utilizing sterilizable flow-through systems containing pipeline steel coupons, corrosion rates determined by nondestructive electrochemical means have indicated that increasing the number of physiological types of microbes inoculated into the system generally increased the severity of the microbially influenced corrosion (MIC). This study reports the MIC of monocultures and combinations of monocultures in an aerobic fresh water system with low sulfate and an anaerobic saline system. In both the aerobic and anaerobic systems, the combination of microbes induced greater MIC responses than the monocultures. In tests involving a combination of microbes in both systems in which one member was a sulfate-reducing bacteria (SRB), the corrosion mechanism was different for the control and the monocultures. This difference was indicated by the phase shift in the electrochemical impedance spectra (EIS). The localization of corrosion, that in many cases is the hallmark of MIC, may be initiated by the inhomogeneities of supposedly smooth metal surfaces. The scanning vibrating electrode technique (SVET) demonstrated non-uniform current densities over carbon steel electrodes polished to a 600 grit finish suggesting pitting and repassivation of pits in sterile medium.

  11. Effects of tree species, stand age and land-use change on soil carbon and nitrogen stock rates in northwestern Turkey

    Directory of Open Access Journals (Sweden)

    Sariyildiz T

    2016-02-01

    Full Text Available Effects of tree species, stand age and land-use change on soil carbon and nitrogen stock rates were investigated in the northwest of Turkey using 4 common tree species as black pine (Pinus nigra Arnold., Scots pine (Pinus sylvestris L., Oriental beech (Fagus orientalis Lipsky and Uludag fir (Abies nordmanniana ssp. bornmuelleriana. Three tree species (black pine, Scots pine and Oriental beech were used to investigate the differences in soil C and N among tree species. Old and young Uludag fir stands and adjacent grassland were used to study the differences in soil C and N with stand age and land-use change. Mineral soil samples were taken from 0-10 cm and 10-20 cm soil depths, and analyzed for pH, soil texture, bulk density, total soil carbon and total nitrogen. The total soil carbon and total nitrogen pools were then calculated by multiplying soil volume, soil bulk density, and the total soil carbon or total nitrogen content. Results showed significant differences in soil carbon and nitrogen contents, carbon/nitrogen ratios and stock rates among the three species, and between old and young fir stands and grassland. In general, when 0-20 cm soil depth was considered, mean soil carbon stock rate was the highest under black pine (79 Mg C ha-1 followed by Scots pine (73 Mg C ha-1 and beech (67 Mg C ha-1, whereas mean soil nitrogen stock rate was the highest under beech (9.57 Mg N ha-1 followed by Scots pine (5.77 Mg N ha-1 and black pine (4.20 Mg N ha-1. Young fir stands showed lower soil carbon stock, but higher soil nitrogen stock rates compared to old fir stands and grassland. Our results demonstrated that tree species, stand tree age and land-use change can have significant effects on soil carbon and nitrogen content and stocks rates. These findings can help to enhance forest management activities, such as selection of tree species for carbon sequestration in plantation systems, design of sustainable agroforestry systems, and improvement of

  12. Individual Investors’ Stock Trading Behavior at Amman Stock Exchange

    OpenAIRE

    Abdel-Raheem F. Fares; Faisal G. Khamis

    2011-01-01

    Many studies investigated the factors that affect investments in stock trading in developed and developing countries, but the investors' characteristics are still not well documented. The Amman Stock Exchange being a small exchange does not use stock trading programs that require advanced mathematical models. Most stock trading is executed the traditional face-to-face way. Therefore, stock trading depends on individual traders’ judgments. Investors’ trading behavior is influenced by several b...

  13. The influence of stocking density on the growth of common carp, Cyprinus carpio, in a recirculating aquaculture system

    OpenAIRE

    Ionica Enache; Victor Cristea; Tudor Ionescu; Săndita Ion

    2011-01-01

    The paper presents some aspects regarding the influence of stocking density on the breeding of the common carp in a recirculating aquaculture system (RAS). The experiment covered a 30 dayperiod. It was conducted in four aquaculture tanks, 500 L/tank, in the recirculating aquaculture pilot system of “Dunarea de Jos” University of Galați. Two kind of stocking density variants were compared: 64 kg/m3 in V1 (B1, B3) and 32 kg/m3 in V2 (B2, B4). The stocking density was: 491 fish in B1, avera...

  14. Organic carbon stocks in Mediterranean soil types under different land uses (Southern Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Munoz-Rojas, M. [CSIC Spin-off, Instituto de Recursos Naturales y Agrobiologia de Sevilla (CSIC), Seville (Spain). Evenor-Tech; Sevilla Univ. (Spain). MED Soil Research Group; Jordan, A.; Zavala, L.M. [Sevilla Univ. (Spain). MED Soil Research Group; Rosa, D. de la [Instituto de Recursos Naturales y Agrobiologia de Sevilla (CSIC), Seville (Spain); Abd-Elmabod, S.K. [Instituto de Recursos Naturales y Agrobiologia de Sevilla (CSIC), Seville (Spain); National Research Centre, Cairo (Egypt). Dept. of Soil and Water Use; Anaya-Romero, M. [CSIC Spin-off, Instituto de Recursos Naturales y Agrobiologia de Sevilla (CSIC), Seville (Spain). Evenor-Tech

    2012-07-01

    Soil C sequestration through changes in land use and management is one of the sustainable and long-term strategies to mitigate climate change. This research explores and quantifies the role of soil and land use as determinants of the ability of soils to store C along Mediterranean systems. Detailed studies of soil organic C (SOC) dynamics are necessary in order to identify factors determining fluctuations and intensity of changes. In this study, SOC contents from different soil and land use types have been investigated in Andalusia (Southern Spain). We have used soil information from different databases, as well as land use digital maps, climate databases and digital elevation models. The average SOC content for each soil control section (0-25, 25-50 and 50-75 cm) was determined and SOC stocks were calculated for each combination of soil and land use type, using soil and land cover maps. The total organic C stocks in soils of Andalusia is 415 Tg for the upper 75 cm, with average values ranging from 15.9 MgC ha{sup -1} (Solonchaks under ''arable land'') to 107.6 MgC ha{sup -1} (Fluvisols from ''wetlands''). Up to 55% of SOC accumulates in the top 25 cm of soil (229.7 Tg). This research constitutes a preliminary assessment for modelling SOC stock under scenarios of land use and climate change. (orig.)

  15. Influence of Carbon on the Electrical Properties of Crustal Rocks

    Energy Technology Data Exchange (ETDEWEB)

    Mathez, E. A.

    2002-11-19

    The report summarizes work to determine the nature and distribution of carbon on microcracks in crystalline rocks by time-of-flight secondary ion mass spectroscopy. It also summarizes the results of a workshop devoted to investigating how carbon in rocks influences electrical conductivity and whether carbon on fracture surfaces can account for the electrical conductivity structure of the crust.

  16. Improved model calculation of atmospheric CO2 increment in affecting carbon stock of tropical mangrove forest

    OpenAIRE

    Jana, Tapan Kumar; Ray, Raghab; Chowdhury, Chumki; Majumder, Natasha; Dutta, Manab Kumar; Mukhopadhyay, Sandip Kumar

    2013-01-01

    Because of the difficulties in setting up arrangements in the intertidal zone for free-air carbon dioxide enrichment experimentation, the responses to increasing atmospheric carbon dioxide in mangrove forests are poorly studied. This study applied box model to overcome this limitation, and the relative changes in present level of reservoirs organic carbon contents in response to the future increase of atmospheric carbon dioxide were examined in the Avicennia-dominated mangrove forest at the l...

  17. Carbon Stocks and Soil C Dynamics: an Investigation of C Sequestration Potential in a Eucalyptus grandis Plantation in Hawaii

    Science.gov (United States)

    Reeves, M. I.; Crow, S. E.; Yost, R.; Turn, S.

    2012-12-01

    Tropical forests are important for many reasons, one of which is their ability to transfer large quantities of CO2 from the atmosphere to living biomass thereby potentially offsetting climate change. If the biomass is then harvested for commercial use, the stored carbon (C) is released back to the atmosphere and as a result, rotational forestry is generally considered C neutral. However, the growth and harvest of forests also affects the soil C cycle through inputs of below ground biomass (BG) in proportion to above ground biomass (ABG). With sustainable management practices, soil can be a long-term sink for C, and provide a climate offset. This study examines the C stocks and dynamics of a E. grandis plantation located in Hawaii. There are two parts: 1) A snapshot of C resources in the plantation, including live biomass C (both BG and ABG) as well as soil C stock, and 2) An investigation of change in soil C stock and pool size with afforestation in E. grandis plantation. ABG C was calculated using published allometric equations and from measurements of the E. grandis trees and ranged from 41-68 Mg C/ha, while BG C ranged from 7-12 Mg C/ha. Added together, the biomass C stocks constitute a mere ≈10% of the soil C stock. To identify the effect of E. grandis afforestation on changes in soil C stock and pools, we compared adjacent pastureland and forested plots in a paired design. Soil C stocks were measured by taking five 1m soil cores in each of the plots. In the pasture, soil C ranged from 431-723 Mg C/ha, while in the E. grandis, it ranged from 544-692 Mg C/ha, an average percent change of 16%. In all plots, soil C decreased by depth. As expected, the surface (0-18) cm cores in the pasture contained more C on average, as grasses tend to input larger amounts of root biomass C in the surface soil. However, in the 20-70 cm depth, the E. grandis plots contained 20-30% more soil C. It is hypothesized that this is due to large differences in rooting depth. The greater

  18. The Influence of information asymmetry on the return and volatility of value and growth stock portfolios

    OpenAIRE

    Max Leandro Ferreira Tavares; Claudio Henrique da Silveira Barbedo; Gustavo Silva Araujo

    2014-01-01

    This article investigates whether the information asymmetry component imbedded in the bid-ask spread helps explain the difference in returns between portfolios composed of value versus growth stocks in the Brazilian market. Additionally, we test whether the portfolios’ volatility has any relation with asymmetry. In this way, we incorporate an element from the market microstructure literature, the information asymmetry component, in the classic asset pricing theory. The results obtained for ...

  19. The influence of stock market listing on human resource management: evidence for France and Britain

    OpenAIRE

    Conway, Neil; Deakin, S.; Suzanne J. Konzelmann; Petit, H; Rebérioux, A.; Wilkinson, F

    2008-01-01

    We use data from REPONSE 2004 and WERS 2004 to analyse whether approaches to HRM differ according to whether an establishment is part of a company with a stock exchange listing. In both countries we find that listing is positively associated with teamworking and performance-related pay, while in France, but not in Britain, it is also linked to worker autonomy and training. Our findings are inconsistent with the claim that shareholder pressure operates as a constraint on the adoption of hig...

  20. Are soils of Iowa USA currently a carbon sink or source? Simulated changes in SOC stock from 1972 to 2007

    Science.gov (United States)

    Liu, S.; Tan, Z.; Li, Z.; Zhao, S.; Yuan, W.

    2011-01-01

    Upscaling the spatial and temporal changes in carbon (C) stocks and fluxes from sites to regions is a critical and challenging step toward improving our understanding of the dynamics of C sources and sinks over large areas. This study simulated soil organic C (SOC) dynamics within 0-100cm depth of soils across the state of Iowa in the USA from 1972 to 2007 using the General Ensemble biogeochemical Modeling System (GEMS). The model outputs with variation coefficient were analyzed and assembled from simulation unit to the state scale based upon major land use types at annual step. Results from this study indicate that soils (within a depth of 0-100cm) in Iowa had been a SOC source at a rate of 190??380kg Cha-1yr-1. This was likely caused by the installation of a massive drainage system which led to the release of SOC from deep soil layers previously protected under poor drainage conditions. The annual crop rotation was another major force driving SOC variation and resulted in spatial variability of annual budgets in all croplands. Annual rate of change of SOC stocks in all land types depended significantly on the baseline SOC levels; soils with higher SOC levels tended to be C sources, and those with lower levels tended to be C sinks. Management practices (e.g., conservation tillage and residue management practices) slowed down the C emissions from Iowa soils, but could not reverse the general trend of net SOC loss in view of the entire state due mainly to a high level of baseline SOC stocks. ?? 2010 Elsevier B.V.

  1. Interactive state-parameter estimation of a crop carbon mass balance model through the assimilation of observed winter wheat carbon flux and stock data

    Science.gov (United States)

    Sus, O.; Williams, M. D.; Gruenwald, T.

    2010-12-01

    Next to the consideration of land management practises, modelling the carbon balance of croplands requires a crop carbon budget model that realistically simulates photosynthesis, ecosystem respiration, soil carbon dynamics, and phenology dependant on crop-specific parameters and carbon allocation patterns. A crop carbon mass balance model is a tool which can aid to answer questions related to cropland carbon sequestration potential, best-practise recommendations, seasonal patterns and amplitude of net carbon exchange (NEE), and prediction of biomass growth and crop yield. However, land management complicates modelling of cropland NEE by largely determining the onset and length of the growing season of agricultural areas. Human decision making on crop cultivars, sowing and harvest dates, and management practices is difficult to simulate, and corresponding reliable data for larger spatial and temporal scales is still sparse. Crop carbon budget models require a specific set of parameters, some of which are poorly understood and are thus of empirical rather than mechanistic nature. Here, we present a study that deals with the assimilation of observations of both carbon flux and stock data into a crop C budget model (SPAc). Our data assimilation procedure (the Ensemble Kalman Filter, EnKF) aims at updating both model states and parameters, so that we will gain insight into optimized parameter values and carbon stock/flux estimates within quantified confidence limits. We obtained measured data of NEE, LAI, and leaf, root, stem, and storage organ dry mass for a winter wheat season in 2005/2006 from the CarboEurope Fluxnet site at Klingenberg/Germany. We conducted several model experiments, for each of which we assimilated a unique combination of data sources. We find that the assimilation of NEE data leads to reduced model error (observed vs. modelled NEE) compared to a model run without data assimilation (a reduction of ~15-20% of RMSE). The assimilated dry mass data on

  2. Soil carbon stocks in response to management changes due to vinasse application in sugarcane production in southeast of Brazil

    Science.gov (United States)

    Fernandes Zani, Caio; Simoes Barneze, Arlete; Clemente Cerri, Carlos

    2014-05-01

    Brazilian commodities, such as ethanol, are looking for sustainable production to suit the international market demands. Thus, studies about variations in soil carbon (C) stocks on the ethanol production are essential. Researches in relation of land use change are already been developed; however information about management changes on the sugarcane production is needed. According to Six et al. (2004) changing the management to conservationist practices can provide an organic matter accumulation to the soil and in a long-term, can increase the soil C stocks. The vinasse is a waste product of the sugarcane industry fuel which contains potassium and considerable quantities of other mineral nutrients. It is estimated that for each litre of ethanol produced is generated approximately 13 L of vinasse. Nowadays, almost all vinasse is applied to the soil as fertigation (Soares et al., 2009). The aim of this study was to evaluate the changes in soil C stocks after the management change with or without vinasse application into sugarcane production in southeast Brazil. The soil sampling was carried out in a fuel industry located in São Paulo state, on July 2013. This area was always used a conventional management at least 34 years with application of mineral fertilizer. However, in the mid of 1990, one part of this area started to use vinasse as source of potassium in sugarcane production. In view of this, we conducted the experiment in these two areas of conventional management: i) without vinasse and ii) with vinasse application. Soil samples were collected in the nine trenches in each site: three trenches at 1 m soil depth and six mini-trenches up to 0.3 m. Samples were used to calculate the bulk density using the undisturbed method with a steel cylinder. Total C was measured by dry combustion on Carbon Analyzer - LECO® CN 2000®. The results showed that C content was a decrease with an increase soil depth. Soil C stocks for areas without vinasse application and vinasse

  3. Toward an integrated monitoring framework to assess the effects of tropical forest degradation and recovery on carbon stocks and biodiversity.

    Science.gov (United States)

    Bustamante, Mercedes M C; Roitman, Iris; Aide, T Mitchell; Alencar, Ane; Anderson, Liana O; Aragão, Luiz; Asner, Gregory P; Barlow, Jos; Berenguer, Erika; Chambers, Jeffrey; Costa, Marcos H; Fanin, Thierry; Ferreira, Laerte G; Ferreira, Joice; Keller, Michael; Magnusson, William E; Morales-Barquero, Lucia; Morton, Douglas; Ometto, Jean P H B; Palace, Michael; Peres, Carlos A; Silvério, Divino; Trumbore, Susan; Vieira, Ima C G

    2016-01-01

    Tropical forests harbor a significant portion of global biodiversity and are a critical component of the climate system. Reducing deforestation and forest degradation contributes to global climate-change mitigation efforts, yet emissions and removals from forest dynamics are still poorly quantified. We reviewed the main challenges to estimate changes in carbon stocks and biodiversity due to degradation and recovery of tropical forests, focusing on three main areas: (1) the combination of field surveys and remote sensing; (2) evaluation of biodiversity and carbon values under a unified strategy; and (3) research efforts needed to understand and quantify forest degradation and recovery. The improvement of models and estimates of changes of forest carbon can foster process-oriented monitoring of forest dynamics, including different variables and using spatially explicit algorithms that account for regional and local differences, such as variation in climate, soil, nutrient content, topography, biodiversity, disturbance history, recovery pathways, and socioeconomic factors. Generating the data for these models requires affordable large-scale remote-sensing tools associated with a robust network of field plots that can generate spatially explicit information on a range of variables through time. By combining ecosystem models, multiscale remote sensing, and networks of field plots, we will be able to evaluate forest degradation and recovery and their interactions with biodiversity and carbon cycling. Improving monitoring strategies will allow a better understanding of the role of forest dynamics in climate-change mitigation, adaptation, and carbon cycle feedbacks, thereby reducing uncertainties in models of the key processes in the carbon cycle, including their impacts on biodiversity, which are fundamental to support forest governance policies, such as Reducing Emissions from Deforestation and Forest Degradation. PMID:26390852

  4. The Influence of Low Carbon Economy on Corporate Social Responsibility

    OpenAIRE

    Jin Lv; Jing Ma; Jianting Li

    2010-01-01

    Under low carbon economy environment, as the pioneer of implementing low carbon economy, corporations have to follow current tendency, change ideas, and take their social responsibility actively, so as to win new competitiveness and achieve sustainable development per se. Firstly, we illustrate the positive influence of low carbon economy on corporate social responsibility through elaborating the internal and external pressure that low carbon economy brings to corporations. Then we propose th...

  5. Improved estimates show large circumpolar stocks of permafrost carbon while quantifying substantial uncertainty ranges and identifying remaining data gaps

    Directory of Open Access Journals (Sweden)

    G. Hugelius

    2014-03-01

    Full Text Available Soils and other unconsolidated deposits in the northern circumpolar permafrost region store large amounts of soil organic carbon (SOC. This SOC is potentially vulnerable to remobilization following soil warming and permafrost thaw, but stock estimates are poorly constrained and quantitative error estimates were lacking. This study presents revised estimates of the permafrost SOC pool, including quantitative uncertainty estimates, in the 0–3 m depth range in soils as well as for deeper sediments (>3 m in deltaic deposits of major rivers and in the Yedoma region of Siberia and Alaska. The revised estimates are based on significantly larger databases compared to previous studies. Compared to previous studies, the number of individual sites/pedons has increased by a factor ×8–11 for soils in the 1–3 m depth range,, a factor ×8 for deltaic alluvium and a factor ×5 for Yedoma region deposits. Upscaled based on regional soil maps, estimated permafrost region SOC stocks are 217 ± 15 and 472 ± 34 Pg for the 0–0.3 m and 0–1 m soil depths, respectively (±95% confidence intervals. Depending on the regional subdivision used to upscale 1–3 m soils (following physiography or continents, estimated 0–3 m SOC storage is 1034 ± 183 Pg or 1104 ± 133 Pg. Of this, 34 ± 16 Pg C is stored in thin soils of the High Arctic. Based on generalised calculations, storage of SOC in deep deltaic alluvium (>3 m to ≤60 m depth of major Arctic rivers is estimated to 91 ± 39 Pg (of which 69 ± 34 Pg is in permafrost. In the Yedoma region, estimated >3 m SOC stocks are 178 +140/−146 Pg, of which 74 +54/−57 Pg is stored in intact, frozen Yedoma (late Pleistocene ice- and organic-rich silty sediments with the remainder in refrozen thermokarst deposits (±16/84th percentiles of bootstrapped estimates. A total estimated mean storage for the permafrost region of ca. 1300–1370 Pg with an uncertainty range of 930–1690 Pg encompasses the combined revised

  6. Taking Stock of Carbon Rights in REDD+ Candidate Countries: Concept Meets Reality

    OpenAIRE

    Lasse Loft; Ashwin Ravikumar; Maria Fernanda Gebara; Thu Thuy Pham; Ida Aju Pradnja Resosudarmo; Samuel Assembe; Jazmín Gonzales Tovar; Esther Mwangi; Krister Andersson

    2015-01-01

    In the discourses on who should benefit from national REDD+ implementation, rights-based approaches are prominent across various countries. Options on how to create viable property rights arrangements are currently being debated by scholars, policy makers and practitioners alike. Many REDD+ advocates argue that assigning carbon rights represents a solution to insecure individual and community property rights. But carbon rights, i.e., the bundle of legal rights to carbon sequestered in biomass...

  7. Modeling the above and below ground carbon and nitrogen stocks in northern high latitude terrestrial ecosystems

    Science.gov (United States)

    ElMasri, B.; Jain, A. K.

    2012-12-01

    Climate change is expected to cause warming in the northern high latitudes, but it is still uncertain what the respond of the northern high latitudes ecosystem will be to such warming. One of the biggest scientific questions is to determine whether northern high latitude ecosystem are or will act as a terrestrial carbon sink or source. Therefore, it is essential to understand and quantify the biogeochemical cycle of the northern high latitude ecosystems in order to predict their respond to climate change. Using a land surface model, the Integrated Science Assessment Model (ISAM) with its coupled carbon-nitrogen cycle, we provide a detail quantification of the carbon and nitrogen in the vegetation pools and the soil carbon for the northern high latitude ecosystems. We focus on soil carbon and vegetation carbon and nitrogen, though we provide results for gross primary production (GPP), autotrophic respiration (Ra), net primary production (NPP), net ecosystem exchange (NEE), and heterotrophic respiration (Rh). In addition, we examine the effect of nitrogen limitation on the carbon fluxes and soil carbon. We present the results for several flux tower sites representative of the tundra and the boreal ecosystems as well as for the northern high latitude region. Our results provide a comprehensive assessment of below and above ground carbon and nitrogen pools in the northern high latitude and the model calibrated parameters can be used to improve the results of other land surface models.

  8. Effect of land-use change on soil organic carbon stocks in the Eastern Usambara Mountain (Tanzania)

    Science.gov (United States)

    Kirsten, Maximilian; Kaaya, Abel; Klinger, Thomas; Feger, Karl-Heinz

    2014-05-01

    A soil organic carbon (SOC) inventory, covering 10 sites with 5 different land-use systems (primary forest, secondary forest, tea plantation, home garden, and cropland) was conducted in the tropical monsoonal Eastern Usambara Mountains (EUM), NE Tanzania. At all sites the environmental factors such as climate and parent material, for soil formation (gneiss), as well as elevation and slope position are highly comparable. The evergreen submontane primary rain forest, which still exists in vast areas in the EUM and the well-known land-use history there provide nearly optimal conditions for the assessment of land-use change effects on soil properties, notably the SOC stocks. We collected horizon-wise samples from soil pit profiles. In addition, samples from fixed depth-intervals were taken from 8 augering points located systematically around each soil pit. The sampling scheme yielded a unique set of soil information (pedological, chemical, and physical) that favours a reliable assessment of SOC stocks and future analytical work on SOM quality and binding mechanisms. The investigated soils are characterized by high clay contents, which increase with depth. Soil pH varies between 3.5 and 5.4 over all land-use systems and horizons, higher pH values could be detected for the agricultural systems in the topsoil, the differences between agricultural and forest systems decrease in the subsoil. The potential cation exchange capacity is in most cases Organic carbon (C) stocks in the soils from the investigated land-use systems cover a wide range between 17.1 and 24.2 kg m-2 (0-100 cm). Variability is even high in the subset of the 3 primary forests. Statistically significant differences between the forest and cropland systems occur in the uppermost depth interval 0-10 cm. Furthermore, the primary forests have higher, but not significantly different SOC stocks in the topsoil (0-40 cm) compared with the cropland systems. In all investigated soils the SOC stocks for the entire

  9. The Unified North American Soil Map and Its Implication on the Soil Organic Carbon Stock in North America

    Science.gov (United States)

    Wei, Y.; Liu, S.; Huntzinger, D. N.; Michalak, A. M.; Post, W. M.; Cook, R. B.; Schaefer, K. M.; Thornton, M.

    2014-12-01

    The Unified North American Soil Map (UNASM) was developed by Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP) to provide more accurate regional soil information for terrestrial biosphere modeling. The UNASM combines information from state-of-the-art US STATSGO2 and Soil Landscape of Canada (SLCs) databases. The area not covered by these datasets is filled by using the Harmonized World Soil Database version 1.21 (HWSD1.21). The UNASM contains maximum soil depth derived from the data source as well as seven soil attributes (including sand, silt, and clay content, gravel content, organic carbon content, pH, and bulk density) for the topsoil layer (0-30 cm) and the subsoil layer (30-100 cm), respectively, of the spatial resolution of 0.25 degrees in latitude and longitude. There are pronounced differences in the spatial distributions of soil properties and soil organic carbon between UNASM and HWSD, but the UNASM overall provides more detailed and higher-quality information particularly in Alaska and central Canada. To provide more accurate and up-to-date estimate of soil organic carbon stock in North America, we incorporated Northern Circumpolar Soil Carbon Database (NCSCD) into the UNASM. The estimate of total soil organic carbon mass in the upper 100 cm soil profile based on the improved UNASM is 365.96 Pg, of which 23.1% is under trees, 14.1% is in shrubland, and 4.6% is in grassland and cropland. This UNASM data has been provided as a resource for use in terrestrial ecosystem modeling of MsTMIP both for input of soil characteristics and for benchmarking model output.

  10. The Unified North American Soil Map and its implication on the soil organic carbon stock in North America

    Directory of Open Access Journals (Sweden)

    S. Liu

    2012-10-01

    Full Text Available The Unified North American Soil Map (UNASM was developed to provide more accurate regional soil information for terrestrial biosphere modeling. The UNASM combines information from state-of-the-art US STATSGO2 and Soil Landscape of Canada (SLCs databases. The area not covered by these datasets is filled with the Harmonized World Soil Database version 1.1 (HWSD1.1. The UNASM contains maximum soil depth derived from the data source as well as seven soil attributes (including sand, silt, and clay content, gravel content, organic carbon content, pH, and bulk density for the top soil layer (0–30 cm and the sub soil layer (30–100 cm respectively, of the spatial resolution of 0.25° in latitude and longitude. There are pronounced differences in the spatial distributions of soil properties and soil organic carbon between UNASM and HWSD, but the UNASM overall provides more detailed and higher-quality information particularly in Alaska and Central Canada. To provide more accurate and up-to-date estimate of soil organic carbon stock in North America, we incorporated Northern Circumpolar Soil Carbon Database (NCSCD into the UNASM. The estimate of total soil organic carbon mass in the upper 100 cm soil profile based on the improved UNASM is 347.70 Pg, of which 24.7% is under trees, 14.2% is under shrubs, and 1.3% is under grasses and 3.8% under crops. This UNASM data will provide a resource for use in land surface and terrestrial biogeochemistry modeling both for input of soil characteristics and for benchmarking model output.

  11. Stock Splits, A Survey

    OpenAIRE

    Yildizhan, Celim

    2006-01-01

    In this survey paper I summarize the literature's findings on the short-run and long-run effects of stock split announcements as well as what happens in the preceding and subsequent years around a stock split event. I also summarize how firm characteristics influence these results. Furthermore, I discuss the various theories regarding why splits occur and why stock return distributions change subsequent to split events. I specifically focus on the changes in the first and second moments of st...

  12. Study on the Carbon Stocks of Soils under Five Kinds of Plantations

    Institute of Scientific and Technical Information of China (English)

    Tao; ZHANG; Fuxu; WAN; Zhengxin; TAN

    2015-01-01

    Based on the field data and laboratory analysis,we studied the soil organic carbon storage and vertical distribution features about five kinds of plantations in Xuyi,and the results showed that soil carbon density in the five forest types changed greatly,with a range of 0. 8-3. 04 kg / m2 for five soil layers. Furthermore,soil carbon density decreased generally with the depth,as well as carbon content. In the whole soil profile,the range of carbon density in these five forests was from 4. 79 kg / m2 to 5. 62 kg / m2. However,60% carbon was concentrated in40 cm depth of soil. The calculated result of soil organic carbon reserve was as follows: Cupressus lusitanica( 50. 264 t / hm2),hackberry( 47. 859 t/hm2),Populus L.( 53. 216 t/hm2),Red bayberry( 49. 581 t/hm2),Amygdalus persica L.( 58. 202 t/hm2),with the average storage of 51. 824 t / hm2,lower than the national average level,so,people should pay attention to the artificial forest tending and management.According to the above analysis,this paper concluded that the afforestation was the effective measure for increasing the soil organic carbon accumulation,and the effects of planting the indigenous tree species Cupressus lusitanica and Amygdalus persica L. were best.

  13. Ecosystem engineering by large grazers enhances carbon stocks in a tidal salt marsh

    NARCIS (Netherlands)

    Elschot, Kelly; Bakker, Jan P.; Temmerman, Stijn; van de Koppel, Johan; Bouma, Tjeerd J.

    2015-01-01

    Grazers can have a large impact on ecosystem processes and are known to change vegetation composition. However, knowledge of how the long-term presence of grazers affects soil carbon sequestration is limited. In this study, we estimated total accumulated organic carbon in soils of a back-barrier sal

  14. Taking Stock of Carbon Rights in REDD+ Candidate Countries: Concept Meets Reality

    Directory of Open Access Journals (Sweden)

    Lasse Loft

    2015-04-01

    Full Text Available In the discourses on who should benefit from national REDD+ implementation, rights-based approaches are prominent across various countries. Options on how to create viable property rights arrangements are currently being debated by scholars, policy makers and practitioners alike. Many REDD+ advocates argue that assigning carbon rights represents a solution to insecure individual and community property rights. But carbon rights, i.e., the bundle of legal rights to carbon sequestered in biomass, present their own set of theoretical and practical challenges. We assess the status and approaches chosen in emerging carbon-rights legislations in five REDD+ countries based on a literature review and country expert knowledge: Peru, Brazil, Cameroon, Vietnam and Indonesia. We find that most countries assessed have not yet made final decisions as to the type of benefit sharing mechanisms they intend to implement and that there is a lack of clarity about who owns rights to carbon as a property and who is entitled to receive benefits. However, there is a trend of linking carbon rights to land rights. As such, the technical and also political challenges that land tenure clarification has faced over the past decades will still need to be addressed in the context of carbon rights.

  15. Dynamic modelling and humus balances as tools for estimating and upscaling soil carbon stock changes in temperate cropland

    Science.gov (United States)

    Oberholzer, Hans-Rudolf; Holenstein, Hildegard; Mayer, Jochen; Leifeld, Jens

    2010-05-01

    Humus balances are simple mathematical tools used by farmers for assessing the overall performance of their management in terms of soil organic matter changes. They are based on humus reproduction factors which themselves mainly depend on crop rotation, residue management, and amount and type of organic fertilization. Dynamic models, on the other hand, are typically complex and need more detailed input data and are designed to calculate the time course of soil carbon content. In both cases, thorough validation is needed to utilize their potential for estimating carbon stock changes. We compared the results of three humus balance methods SALCA-SQ (Neyroud 1997), VDLUFA method (VDLUFA 2004), Humod (Brock et al. 2008) and the RothC model with measured soil carbon stocks in a long-term experiment in Switzerland for the period 1977-2005 (Fliessbach et al 2007). The field trial comprises various minerally and organically fertilized treatments, the latter differing in the amount and composition of organics applied. All methods were able to distinguish systematic management effects on soil organic carbon (SOC). However, only those SOC trajectories calculated with the dynamic model RothC matched measured stocks quantitatively. For both, humus balances and dynamic modelling the result strongly depended on parameterization of organic fertilizers, i.e. its stability and organic matter content. Therefore, incomplete information on the amount and composition of organic fertilizer and lack of knowledge about its potential for humus reproduction is regarded an uncertainty in both dynamic modelling and humus balance calculation, and seems to be a major drawback for the reliable application of these approaches at the regional scale. Our results stress the need for more detailed and harmonized data bases of organic fertilizer composition and application rates. References Brock C., Hoyer U., Leithold G., Hülsbergen K.-J., 2008. Entwicklung einer praxisanwendbaren Methode der

  16. CARBO-CONTROLE. Quantification of the carbon flux and stocks at the european and national scale

    International Nuclear Information System (INIS)

    The CARBO-CONTROLE project aims to evaluate the different methodologies to estimate the CO2 flux at the european, national and regional scale. The strategy is to combine a crumbling, down scaling, of the flux at a big scale, by inverting the atmospheric CO2 measures with a aggregation, up scaling, of the national stocks and flux from the climatic parameters of a model of ecosystems.They show that with the monthly data of the global network of CO2 monitoring stations, it is possible to obtain an estimation of the european flux. Meanwhile the errors bond to the leak of continental stations are of the order of the flux average. (A.L.B.)

  17. Mangrove Blue Carbon stocks and change estimation from PolInSAR, Lidar and High Resolution Stereo Imagery combined with Forest Cover change mapping

    Science.gov (United States)

    Zalles, V.; Fatoyinbo, T. E.; Simard, M.; Lagomasino, D.; Lee, S. K.; Trettin, C.; Feliciano, E. A.; Hansen, M.; John, P.

    2015-12-01

    Mangroves and tidal wetlands have the highest carbon density among terrestrial ecosystems. Although they only represent 3 % of the total forest area (or 0.01 % of land area), C emissions from mangrove destruction alone at current rates could be equivalent to 10 % of carbon emissions from deforestation. One of the main challenges to implementing carbon mitigation projects is measuring carbon, efficiently, effectively, and safely. In mangroves especially, the extreme difficulty of the terrain has hindered the establishment of sufficient field plots needed to accurately measure carbon on the scale necessary to relate remotely sensed measurements with field measurements at accuracies required for REDD and other C trading mechanisms. In this presentation we will showcase the methodologies for, and the remote sensing products necessary to implement MRV (monitoring, reporting and verification) systems in Coastal Blue Carbon ecosystems. Specifically, we will present new methods to estimate aboveground biomass stocks and change in mangrove ecosystems using remotely sensed data from Interferometric SAR from the TanDEM-X mission, commercial airborne Lidar, High Resolution Stereo-imagery, and timeseries analysis of Landsat imagery in combination with intensive field measurements of above and belowground carbon stocks. Our research is based on the hypothesis that by combining field measurements, commercial airborne Lidar, optical and Pol-InSAR data, we are able to estimate Mangrove blue carbon storage with an error under 20% at the project level and permit the evaluation of UNFCCC mechanisms for the mitigation of carbon emissions from coastal ecosystems.

  18. Disclosure, Conservatism and their Influence on Cost of Capital of the Companies Accepted by Tehran Stock Exchange (TSE

    Directory of Open Access Journals (Sweden)

    R. Zare

    2013-05-01

    Full Text Available This study attempts to examine the relevance of Disclosure, conservatism and their influence on cost of capital of the companies accepted by Tehran Stock Exchange (TSE and Compare the relative information content of them. Based on sampling, 113 firms from Tehran Stock Exchange (TSE were selected and examined during 2003 to 2009. The results support the priority of accounting figures over dividend policy. The results show there is some significant relation between the conservatism rate and cost of capital. The relation between the conservatism and cost of capital is on the basis of the Spence (1973. By virtue of the theory the companies benefit from the conservative accounting policy as a quality sign. When the conservative accounting policy is chosen it indicates a positive qualitative sign. Higher quality indicates the information risk of a company decreases probably; when the information risk of a company decreases the cost of capital decreases, too. Also the results show a significant relation between the disclosure rate and cost of capital namely when the disclosure rate of a company is higher (better the usual shares cost is lower.

  19. The influence of different stocking densities on biochemical composition of rainbow trout meat reared in a recirculating aquaculture system

    Directory of Open Access Journals (Sweden)

    Mirela Cretu

    2014-05-01

    Full Text Available The aim of this study is to evaluate the biochemical composition of rainbow trout meat, reared in a recirculating aquaculture system, at different stocking densities (DS1-2,64 kg/m3, DS2-5,16 kg/m3, DS3-7,12 kg/m3, DS4-9,42 kg/m3. The analyses were performed in the research laboratory of Aquaculture, Environmental Science and Cadastre Department – Faculty of Food Science and Engineering, from ,,Dunarea de Jos’’University of Galati. The content of meat proteins, fats, dry substance and ash was determined. After a 33 days experimental trial, the biochemical analysis of meat from all four experimental variants shows that protein content was higher in DS1 and DS4 variants, while the smallest amount of fats was quantified at DS1 and DS2 variants, without significant differences (p >0.05 for none of the biochemical compounds analyzed, at the mean comparison on experimental variants. Thus, it can be concluded that biochemical composition of rainbow trout meat was not influenced by the tested stocking densities.

  20. Impact de l’agroforesterie sur le stock de carbone organique du sol sous climat méditerranéen

    OpenAIRE

    Cardinael, Rémi; Chevallier, Tiphaine; Barthès, Bernard; dupraz, Christian; Chenu, Claire

    2014-01-01

    Le stock de carbone (C) des sols est extrêmement sensible au changement d’usage des terres, et peut à la fois être une source ou un puits de CO2 atmosphérique. Les systèmes agroforestiers, associations d’arbres et de cultures sur une même parcelle, permettent de stocker du C dans la biomasse ligneuse aérienne et souterraine des arbres. De tels systèmes pourraient également améliorer les stocks de C organique du sol, de part des entrées de C plus importantes, comme les litières ...

  1. Geographic variability in organic carbon stock and accumulation rate in sediments of East and Southeast Asian seagrass meadows

    Science.gov (United States)

    Miyajima, Toshihiro; Hori, Masakazu; Hamaguchi, Masami; Shimabukuro, Hiromori; Adachi, Hiroshi; Yamano, Hiroya; Nakaoka, Masahiro

    2015-04-01

    Organic carbon (OC) stored in the sediments of seagrass meadows has been considered a globally significant OC reservoir. However, the sparsity and regional bias of studies on long-term OC accumulation in coastal sediments have limited reliable estimation of the capacity of seagrass meadows as a global OC sink. We evaluated the amount and accumulation rate of OC in sediment of seagrass meadows and adjacent areas in East and Southeast Asia. In temperate sites, the average OC concentration in the top 30 cm of sediment was higher in seagrass meadows (780-1080 mmol g-1) than in sediments without seagrass cover (52-430 mmol g-1). The average OC in the top 30 cm of subtropical and tropical seagrass meadow sediments ranged from 140 to 440 mmol g-1. Carbon isotope mass balancing suggested that the contribution of seagrass-derived carbon to OC stored in sediments was often relatively minor (temperate: 10-40%; subtropical: 35-82%; tropical: 4-34%) and correlated to the habitat type, being particularly low in estuarine habitats. Stock of OC in the top meter of sediment of all the studied meadows ranged from 38 to 120 Mg ha-1. The sediment accumulation rates were estimated by radiocarbon dating of six selected cores (0.32-1.34 mm yr-1). The long-term OC accumulation rates calculated from the sediment accumulation rate and the top 30 cm average OC concentration for the seagrass meadows (24-101 kg ha-1 yr-1) were considerably lower than the OC accumulation rates previously reported for Mediterranean Posidonia oceanica meadows (580 kg ha-1 yr-1 on average). Current estimates for the global carbon sink capacity of seagrass meadows, which rely largely on Mediterranean studies, may be considerable overestimations.

  2. How will conversion to organic cereal production affect carbon stocks in Swedish agricultural soils?

    OpenAIRE

    Andrén, Olof; Kätterer, Thomas; Kirchmann, Holger

    2008-01-01

    Soil carbon changes were modelled over 30 years with the focus on cereal crops, since leys are often managed similarly in organic and conventional agriculture. Other crops were not considered due to difficulties in large-scale cropping of oilseed rape and potatoes organically because of pest problems. Four scenarios were used: 0%, 8% (current), 20% and 100% organic cereal production. Conversion to organic cereal crop production was found to reduce the amount of carbon stored as organic matter...

  3. Changes in forest biomass carbon stock in the Pearl River Delta between 1989 and 2003

    Institute of Scientific and Technical Information of China (English)

    YANG Kun; GUAN Dongsheng

    2008-01-01

    Forest ecosystems play a significant role in maintaining climate stability at the regional and global scales as an important carbon sink. Regional forest carbon storage and its dynamic changes in the Pearl River Delta have been estimated using the continuous biomass expansion factor (BEF) method based on field measurements of forests plots in different age classes and forest inventory data of three periods (1989-1993, 1994-1998, 1999-2003). The results show that regional carbon storage increased by 16.76%, from 48.57×106 to 56.71×106 tons, 80% of which was stored in forest stands. Carbon storage of other types of vegetation, with the exception of shrubland and woodland, increased. Carbon density of the regional forest increased by 14.31%, from 19.08 to 21.81 ton/hm2. Potential carbon storage of the regional forest may reach 39.96×107 tons when the forest biomass peaks with succession.

  4. Public Review Draft: A Method for Assessing Carbon Stocks, Carbon Sequestration, and Greenhouse-Gas Fluxes in Ecosystems of the United States Under Present Conditions and Future Scenarios

    Science.gov (United States)

    Bergamaschi, Brian A.; Bernknopf, Richard; Clow, David; Dye, Dennis; Faulkner, Stephen; Forney, William; Gleason, Robert; Hawbaker, Todd; Liu, Jinxun; Liu, Shu-Guang; Prisley, Stephen; Reed, Bradley; Reeves, Matthew; Rollins, Matthew; Sleeter, Benjamin; Sohl, Terry; Stackpoole, Sarah; Stehman, Stephen; Striegl, Rob; Wein, Anne; Zhu, Zhi-Liang

    2010-01-01

    The Energy Independence and Security Act of 2007 (EISA), Section 712, authorizes the U.S. Department of the Interior to develop a methodology and conduct an assessment of the Nation's ecosystems focusing on carbon stocks, carbon sequestration, and emissions of three greenhouse gases (GHGs): carbon dioxide, methane, and nitrous oxide. The major requirements include (1) an assessment of all ecosystems (terrestrial systems, such as forests, croplands, wetlands, shrub and grasslands; and aquatic ecosystems, such as rivers, lakes, and estuaries), (2) an estimation of annual potential capacities of ecosystems to increase carbon sequestration and reduce net GHG emissions in the context of mitigation strategies (including management and restoration activities), and (3) an evaluation of the effects of controlling processes, such as climate change, land use and land cover, and wildlfires. The purpose of this draft methodology for public review is to propose a technical plan to conduct the assessment. Within the methodology, the concepts of ecosystems, carbon pools, and GHG fluxes used for the assessment follow conventional definitions in use by major national and international assessment or inventory efforts. In order to estimate current ecosystem carbon stocks and GHG fluxes and to understand the potential capacity and effects of mitigation strategies, the method will use two time periods for the assessment: 2001 through 2010, which establishes a current ecosystem GHG baseline and will be used to validate the models; and 2011 through 2050, which will be used to assess future potential conditions based on a set of projected scenarios. The scenario framework is constructed using storylines of the Intergovernmental Panel on Climate Change (IPCC) Special Report Emission Scenarios (SRES), along with initial reference land-use and land-cover (LULC) and land-management scenarios. An additional three LULC and land-management mitigation scenarios will be constructed for each

  5. Influences of Seasoned Equity Offerings on Stock Return of Ho Chi Minh Market

    Directory of Open Access Journals (Sweden)

    Ho Viet Tien

    2013-01-01

    Full Text Available This paper investigated the impact of seasoned equity offerings (SEO on stock return of listed companies in Ho Chi Minh City market using the method “event study” which has been basically formed by Campbell, Lo, and MacKinlay (1997. The sample includes 332 SEOs from 2007 to 2010. The main findings show evidence that the Ho Chi Minh City market was not efficient in terms of the semi-strong form because the price has increased significantly on the ex-right date, day 0. In an opposite way, the market also reacted significantly negatively from T-4 to T-2. There are some significant impacts of timing on issue methods – equity right issues were in priority for favorable time and issues as “dividend by stocks” were chosen during unfavorable time.

  6. Large-Scale Mapping of Carbon Stocks in Riparian Forests with Self-Organizing Maps and the k-Nearest-Neighbor Algorithm

    Directory of Open Access Journals (Sweden)

    Leonhard Suchenwirth

    2014-07-01

    Full Text Available Among the machine learning tools being used in recent years for environmental applications such as forestry, self-organizing maps (SOM and the k-nearest neighbor (kNN algorithm have been used successfully. We applied both methods for the mapping of organic carbon (Corg in riparian forests due to their considerably high carbon storage capacity. Despite the importance of floodplains for carbon sequestration, a sufficient scientific foundation for creating large-scale maps showing the spatial Corg distribution is still missing. We estimated organic carbon in a test site in the Danube Floodplain based on RapidEye remote sensing data and additional geodata. Accordingly, carbon distribution maps of vegetation, soil, and total Corg stocks were derived. Results were compared and statistically evaluated with terrestrial survey data for outcomes with pure remote sensing data and for the combination with additional geodata using bias and the Root Mean Square Error (RMSE. Results show that SOM and kNN approaches enable us to reproduce spatial patterns of riparian forest Corg stocks. While vegetation Corg has very high RMSEs, outcomes for soil and total Corg stocks are less biased with a lower RMSE, especially when remote sensing and additional geodata are conjointly applied. SOMs show similar percentages of RMSE to kNN estimations.

  7. Optimal capture and sequestration from the carbon emission flow and from the atmospheric carbon stock with heterogeneous energy consuming sectors

    OpenAIRE

    Amigues, Jean-Pierre; Lafforgue, Gilles; MOREAUX Michel

    2010-01-01

    We characterize the optimal exploitation paths of two primary energy resources. The first one is a non-renewable polluting resource, the second one a pollution-free renewable resource. Both resources can supply the energy needs of two sectors. Sector 1 is able to reduce the potential carbon emissions generated by its non-renewable energy consumption at a reasonable cost while sector 2 cannot. Another possibility is to capture the carbon spread in the atmosphere but at a significantly higher c...

  8. Re-evaluation of forest biomass carbon stocks and lessons from the world's most carbon-dense forests

    OpenAIRE

    Keith, Heather; Mackey, Brendan G.; Lindenmayer, David B

    2009-01-01

    From analysis of published global site biomass data (n = 136) from primary forests, we discovered (i) the world's highest known total biomass carbon density (living plus dead) of 1,867 tonnes carbon per ha (average value from 13 sites) occurs in Australian temperate moist Eucalyptus regnans forests, and (ii) average values of the global site biomass data were higher for sampled temperate moist forests (n = 44) than for sampled tropical (n = 36) and boreal (n = 52) forests (n is number of site...

  9. Evaluation of carbon stocks in above- and below-ground biomass in Central Africa: case study of Lesio-louna tropical rainforest of Congo

    Science.gov (United States)

    Liu, X.; Ekoungoulou, R.; Loumeto, J. J.; Ifo, S. A.; Bocko, Y. E.; Koula, F. E.

    2014-07-01

    The study was aimed to estimate the carbon stocks of above- and below-ground biomass in Lesio-louna forest of Congo. The methodology of allometric equations was used to measure the carbon stocks of Lesio-louna natural forest. We are based precisely on the model II which is also called non-destructive method or indirect method of measuring carbon stocks. While there has been use of parameters such as the DBH and wood density. The research was done with 22 circular plots each 1256 m2. In the 22 plots studied, 19 plots are in the gallery forest and three plots in the secondary forest. Also, 22 circular plots were distributed in 5 sites studies of Lesio-louna forest, including: Inkou forest island, Iboubikro, Ngoyili, Blue lake and Ngambali. So, there are two forest types (secondary forest and gallery forest) in this forest ecosystem. In the 5 sites studied, we made measurements on a total of 347 trees with 197 trees for the class of 10-30 cm diameter, 131 trees for the class of 30-60 cm diameter and 19 trees in the diameter class > 60 cm. The results show that in the whole forest, average carbon stock for the 22 plots of the study was 168.601 t C ha-1 for AGB, or 81% and 39.551 t C ha-1 for BGB, or 19%. The total carbon stocks in all the biomass was 3395.365 t C for AGB, which is 3.395365 × 10-6 Gt C and 909.689934 t C for BGB, which was 9.09689934 × 10-7 Gt C. In this forest, the carbon stock was more important in AGB compared to BGB with respectively 3395.365 t C against 909.689934 t C. Plot10 (AGB = 363.899 t C ha-1 and BGB = 85.516 t C ha-1) was the most dominant in terms of carbon quantification in Lesio-louna.

  10. Evaluation of carbon stocks in above- and below-ground biomass in Central Africa: case study of Lesio-louna tropical rainforest of Congo

    Directory of Open Access Journals (Sweden)

    X. Liu

    2014-07-01

    Full Text Available The study was aimed to estimate the carbon stocks of above- and below-ground biomass in Lesio-louna forest of Congo. The methodology of allometric equations was used to measure the carbon stocks of Lesio-louna natural forest. We are based precisely on the model II which is also called non-destructive method or indirect method of measuring carbon stocks. While there has been use of parameters such as the DBH and wood density. The research was done with 22 circular plots each 1256 m2. In the 22 plots studied, 19 plots are in the gallery forest and three plots in the secondary forest. Also, 22 circular plots were distributed in 5 sites studies of Lesio-louna forest, including: Inkou forest island, Iboubikro, Ngoyili, Blue lake and Ngambali. So, there are two forest types (secondary forest and gallery forest in this forest ecosystem. In the 5 sites studied, we made measurements on a total of 347 trees with 197 trees for the class of 10–30 cm diameter, 131 trees for the class of 30–60 cm diameter and 19 trees in the diameter class > 60 cm. The results show that in the whole forest, average carbon stock for the 22 plots of the study was 168.601 t C ha−1 for AGB, or 81% and 39.551 t C ha−1 for BGB, or 19%. The total carbon stocks in all the biomass was 3395.365 t C for AGB, which is 3.395365 × 10–6 Gt C and 909.689934 t C for BGB, which was 9.09689934 × 10–7 Gt C. In this forest, the carbon stock was more important in AGB compared to BGB with respectively 3395.365 t C against 909.689934 t C. Plot10 (AGB = 363.899 t C ha−1 and BGB = 85.516 t C ha−1 was the most dominant in terms of carbon quantification in Lesio-louna.

  11. Influence of carbon nanomaterials on the properties of paint coatings

    Science.gov (United States)

    Zhdanok, S. A.; Krauklis, A. V.; Borisevich, K. O.; Prokopchuk, N. P.; Nikolaichik, A. V.; Stanovoi, P. G.

    2011-11-01

    The conditions for obtaining carbon nanomaterials with the use of a low-temperature plasma are described. The product obtained was analyzed using the electron microscopy and a laser diffraction particle-size analyzer. The influence of the carbon nanomaterials on the physicochemical properties of paint coatings, their adhesion, impact and bending strengths, hardness, and protection characteristics was investigated.

  12. Stocks and fluxes of carbon associated with land use change in Southeast Asian tropical peatlands: A review

    Science.gov (United States)

    Hergoualc'h, Kristell; Verchot, Louis V.

    2011-06-01

    The increasing and alarming trend of degradation and deforestation of tropical peat swamp forests may contribute greatly to climate change. Estimates of carbon (C) losses associated with land use change in tropical peatlands are needed. To assess these losses we examined C stocks and peat C fluxes in virgin peat swamp forests and tropical peatlands affected by six common types of land use. Phytomass C loss from the conversion of virgin peat swamp forest to logged forest, fire-damaged forest, mixed croplands and shrublands, rice field, oil palm plantation, and Acacia plantation were calculated using the stock difference method and estimated at 116.9 ± 39.8, 151.6 ± 36.0, 204.1 ± 28.6, 214.9 ± 28.4, 188.1 ± 29.8, and 191.7 ± 28.5 Mg C ha-1, respectively. Total C loss from uncontrolled fires ranged from 289.5 ± 68.1 Mg C ha-1 in rice fields to 436.2 ± 77.0 Mg C ha-1 in virgin peat swamp forest. We assessed the effects of land use change on C stocks in the peat by looking at how the change in vegetation cover altered the main C inputs (litterfall and root mortality) and outputs (heterotrophic respiration, CH4 flux, fires, and soluble and physical removal) before and after conversion. The difference between the soil input-output balances in the virgin peat swamp forest and in the oil palm plantation gave an estimate of peat C loss of 10.8 ± 3.5 Mg C ha-1 yr-1. Peat C loss from other land use conversions could not be assessed due to lack of data, principally on soil heterotrophic respiration rates. Over 25 years, the conversion of tropical virgin peat swamp forest into oil palm plantation represents a total C loss from both biomass and peat of 427.2 ± 90.7 Mg C ha-1 or 17.1 ± 3.6 Mg C ha-1 yr-1. In all situations, peat C loss contributed more than 63% to total C loss, demonstrating the urgent need in terms of the atmospheric greenhouse gas burden to protect tropical virgin peat swamp forests from land use change and fires.

  13. Soil organic carbon stocks and composition under grazed and ungrazed Kobresia pygmaea pasture of the Tibetan Plateau

    Science.gov (United States)

    Breidenbach, Andreas; Schleuß, Per; Kuzyakov, Yakov; Guggenberger, Georg

    2015-04-01

    Kobresia pastures represent the world's largest alpine ecosystem and an important sink but also a potential source of CO2. Specific features of Kobresia root mats provide unique mechanisms protecting against degradation even by moderate overgrazing and leading to large carbon storage in soil. Thus it is necessary to analyse how management- and/or climate-induced changes in above and belowground litter production affect the OC stock and composition in these grassland soils. We analyzed soils from a grazing exclosure experiment to study alterations using elemental analysis and analysis of solvent extractable as well as hydrolysable aliphatic lipids (e.g. n-alkanes, n-alkanols, n-alkanoic acids, as well as cutin- and suberin-derived hydroxy-fatty acids). We investigated bulk soils and density fractions taken from three different depth increments (0-5 cm, 5-15 cm and 15-35 cm) from two grazed and two ungrazed plots. Grazing exclosure resulted in an OC gain up to 1.0 kg m-2 at the site where plant community changes after grazing cessation were most pronounced. These OC gains were caused by increased stocks of OC in the particulate fraction of the two deeper soil increments whereas the OC of the mineral associated fraction and the depth increment 0-5 cm showed no changes. Moreover, the concentration of solvent extractable C16 and C18 acids decreased in the particulate fraction whereas the concentration of C24 and C26 acids increased. Our results show that seven years of grazing cessation increased the OC-pool with short turnover rates and changed its chemical composition, but had no major impact on the more stable OC pools of the mineral soil.

  14. Climate change impacts on carbon stocks of Mediterranean soils: a CarboSOIL model application

    Science.gov (United States)

    Muñoz-Rojas, Miriam; Jordán, Antonio; Zavala, Lorena M.; de la Rosa, Diego; González-Peñaloza, Félix A.; Kotb Abd-Elmabod, Sameh; Anaya-Romero, María

    2013-04-01

    The Mediterranean area is among the most sensible regions to climate change and large increases in temperature as well as drought periods and heavy rainfall events have been forecasted in the next decades. Soil organic C (SOC) prevents from soil erosion and desertification and enhances bio-diversity. Therefore, soil C accumulation capacity should be considered regarding to adaptation strategies to climate change in view of the high resilience of soils with an adequate level of organic C to a warming, drying climate. In this research we propose a new methodology to predict SOC contents and changes under different climate change scenarios: CarboSoil model. CarboSOIL model is part of the land evaluation decision support system MicroLEIS DSS and was designed as a GIS tool to predict SOC stored at different depths (0-25, 25-50, 50-75 and 0-75 cm). The model includes site, land use, climate and soil variables, and was trained and validated in two Mediterranean areas (Andalusia, S Spain, and Valencia, E Spain, respectively) and applied in different IPCC scenarios (A1B, A2 and B1) according to different Global Climate Models (BCCR-BCM2, CNRMCM3 and ECHAM5) downscaled for the region of Andalusia. Output data were linked to spatial datasets (soil and land use) and spatial analysis was performed to quantify organic C stocks for different soil types under a range of land uses. Results highlight the negative impact of climate change on SOC. In particular, SOC contents are expected to decrease severely in the medium-high emissions A2 scenario by 2100. There is an overall trend towards decreasing of organic C stocks in the upper soil sections (0-25 cm and 25-50 cm) of most soil types. In Regosols under "open spaces" 80.4% of the current SOC is predicted to be lost in 2100 under the A2 scenario. CarboSOIL has proved its ability to predict the short, intermediate and long-term trends (2040s, 2070s and 2100s) of SOC dynamics and sequestration under projected future scenarios of

  15. Agricultural influences on carbon emissions and sequestration

    OpenAIRE

    Ball, Andrew S.; Pretty, Jules N.

    2002-01-01

    This report was presented at the UK Organic Research 2002 Conference. Agricultural systems contribute to carbon emissions through several mechanisms: the direct use of fossil fuels in farm operations, the indirect use of embodied energy in inputs that are energy intensive to manufacture (e.g. fertilizers), and the cultivation of soils resulting in the loss of soil organic matter. However agriculture can also sequester carbon when organic matter accumulates in the soil or above-ground woody bi...

  16. Net changes in aboveground woody carbon stock in western juniper woodlands, 1946-1998

    Science.gov (United States)

    Strand, Eva K.; Vierling, Lee A.; Smith, Alistair M. S.; Bunting, Stephen C.

    2008-03-01

    Although regional increases in woody plant cover in semiarid ecosystems have been identified as a worldwide phenomenon affecting the global carbon budget, quantifying the impact of these vegetation shifts on C pools and fluxes is challenging. Challenges arise because woody encroachment is governed by ecological processes that occur at fine spatial resolutions (1-10 m) and, in many cases, at slow (decadal-scale) temporal rates over large areas. We therefore analyzed time series aerial photography, which exhibits both the necessary spatial precision and temporal extent, to quantify the expansion of western juniper into sagebrush steppe landscapes in southwestern Idaho. We established upper and lower bounds of aboveground woody carbon change across the landscape via two-dimensional spatial wavelet analysis, image texture analysis, and field data collection. Forty-eight 100-ha blocks across a 330,000-ha region were stratified by topography, soil characteristics, and land stewardship for analyses. Across the area we estimate aboveground woody carbon accumulation rates of 3.3 gCm-2yr-1 and 10.0 gCm-2yr-1 using the wavelet and texture method, respectively, during the time period 1946-1998. Carbon accumulation rates were significantly affected by soil properties and were highly dependent on the spatial and temporal scales of analysis. For example, at a 100-ha scale the aboveground carbon accumulation varied from -1.7 to 9.9 gCm-2yr-1, while at the 1-ha scale the range of variability increased to -11 to 22 gCm-2yr-1. These values are an order of magnitude lower than those previously suggested due to woody encroachment, highlighting the need for examining multiple spatial scales when accounting for changes in terrestrial carbon storage.

  17. Permafrost collapse alters soil carbon stocks, respiration, CH4 , and N2O in upland tundra.

    Science.gov (United States)

    Abbott, Benjamin W; Jones, Jeremy B

    2015-12-01

    Release of greenhouse gases from thawing permafrost is potentially the largest terrestrial feedback to climate change and one of the most likely to occur; however, estimates of its strength vary by a factor of thirty. Some of this uncertainty stems from abrupt thaw processes known as thermokarst (permafrost collapse due to ground ice melt), which alter controls on carbon and nitrogen cycling and expose organic matter from meters below the surface. Thermokarst may affect 20-50% of tundra uplands by the end of the century; however, little is known about the effect of different thermokarst morphologies on carbon and nitrogen release. We measured soil organic matter displacement, ecosystem respiration, and soil gas concentrations at 26 upland thermokarst features on the North Slope of Alaska. Features included the three most common upland thermokarst morphologies: active-layer detachment slides, thermo-erosion gullies, and retrogressive thaw slumps. We found that thermokarst morphology interacted with landscape parameters to determine both the initial displacement of organic matter and subsequent carbon and nitrogen cycling. The large proportion of ecosystem carbon exported off-site by slumps and slides resulted in decreased ecosystem respiration postfailure, while gullies removed a smaller portion of ecosystem carbon but strongly increased respiration and N2 O concentration. Elevated N2 O in gully soils persisted through most of the growing season, indicating sustained nitrification and denitrification in disturbed soils, representing a potential noncarbon permafrost climate feedback. While upland thermokarst formation did not substantially alter redox conditions within features, it redistributed organic matter into both oxic and anoxic environments. Across morphologies, residual organic matter cover, and predisturbance respiration explained 83% of the variation in respiration response. Consistent differences between upland thermokarst types may contribute to the

  18. Ten Year Evaluation of Carbon Stock in Mangrove Plantation Reforested from an Abandoned Shrimp Pond

    OpenAIRE

    Jirasak Chukwamdee; Wijarn Meepol; Keiyo Morimune; Naohiro Matsui

    2012-01-01

    Forest carbon stocks—both in terms of the standing biomass and the soil organic carbon (OC)—were monitored in the mangrove plantation reforested from an abandoned shrimp pond for the 10 years following land excavation. Excavation to a level of 25 cm below the existing ground level increased the inundation time of tidal water from 463 to 7,597 hours per year, resulting in a significant increase of survival/growth rates for planted mangrove species, Rhizophora mucronata (RM...

  19. Stock Markets

    Institute of Scientific and Technical Information of China (English)

    亚玲

    2005-01-01

    There are stock markets in large cities in many countries. Stock markets in Paris, London, Tokyo, Shanghai and New York are among the largest and most well-known. The stock market, also called stock exchange, is a place where people can buy or sell shares of a factory or company. And each share means certain ownership of a factory or company.

  20. Soil organic carbon stocks in Alaska estimated with spatial and pedon data

    Science.gov (United States)

    Bliss, N.B.; Maursetter, J.

    2010-01-01

    Temperatures in high-latitude ecosystems are increasing faster than the average rate of global warming, which may lead to a positive feedback for climate change by increasing the respiration rates of soil organic C. If a positive feedback is confirmed, soil C will represent a source of greenhouse gases that is not currently considered in international protocols to regulate C emissions. We present new estimates of the stocks of soil organic C in Alaska, calculated by linking spatial and field data developed by the USDA NRCS. The spatial data are from the State Soil Geographic database (STATSGO), and the field and laboratory data are from the National Soil Characterization Database, also known as the pedon database. The new estimates range from 32 to 53 Pg of soil organic C for Alaska, formed by linking the spatial and field data using the attributes of Soil Taxonomy. For modelers, we recommend an estimation method based on taxonomic subgroups with interpolation fot missing areas, which yields an estimate of 48 Pg. This is a substantial increase over a magnitude of 13 Pg estimated from only the STATSGO data as originally distributed in 1994, but the increase reflects different estimation methods and is not a measure of the change in C on the landscape. Pedon samples were collected between 1952 and 2002, so the results do not represent a single point in time. The linked databases provide an improved basis for modeling the impacts of climare change on net ecosystem exchange. ?? Soil Science Society of America. All rights reserved.

  1. Ecosystem engineering by large grazers enhances carbon stocks in a tidal salt marsh

    NARCIS (Netherlands)

    Elschot, K.; Bakker, J.P.; Temmerman, S.; van de Koppel, J.; Bouma, T.J.

    2015-01-01

    Grazers can have a large impact on ecosystem processes and are known to changevegetation composition. However, knowledge of how the long-term presence of grazers affectssoil carbon sequestration is limited. In this study, we estimated total accumulated organic carbonin soils of a back-barrier salt m

  2. Trends in carbon stocks in Dutch soils: datasets and modeling results

    NARCIS (Netherlands)

    Chardon, W.J.; Heesmans, H.I.M.; Kuikman, P.J.

    2009-01-01

    Observations on trends in soil organic carbon (SOC) in agricultural soils is an important basis for mandatory reporting of emission of greenhouse gases from land use. A decrease indicates that these soils are a source of CO2, an increase that they are a sink. IPCC Good Practice Guidance generally as

  3. THE MOMENTUM EFFECT EXEMPLIFIES THE INFLUENCE OF INVESTORS’ IRRATIONAL BEHAVIOUR ON CHANGING PRICES OF SHARES AND STOCKS: AN ANALYSIS OF THE MOMENTUM EFFECT ON THE WARSAW STOCK EXCHANGE

    Directory of Open Access Journals (Sweden)

    Paweł Merło

    2015-08-01

    Full Text Available An efficient market should not show any anomalies. When new information reaches a market which is efficient, it should automatically translate into prices of assets, which ought to eliminate the possibility of gaining an advantage over other investors, thus preventing excess profits. However, studies on capital markets indicate that in reality it is possible to earn unusually high profits by taking advantage of certain anomalies which occur on a given market. Among such anomalies there is the momentum effect. This study performed on the Stock Exchange in Warsaw has shown that the momentum effect occurred throughout the entire analyzed time period. Positive returns demonstrated for investment strategies based on the momentum effect were unexplainable by the classical theory of finances. A correlation was found between the economic situation on the stock exchange and portfolio return rates, but it was too weak to attribute the effect to a single decisive factor. In addition, the returns from investments based on the momentum effect were statistically higher in January than in the other months, which was caused by the January effect, stimulating the occurrence of statistically higher returns at the beginning of a year rather than later on during the analyzed period of time. Research in this field carried out in other countries justifies the claim that there are many irrational factors which together create the momentum effect on the stock exchange. Thus, it is possible to conclude that irrational decisions may have strong impact on the pricing of stocks on the capital market. The momentum effect persisted throughout the entire analyzed period, although its power changed cyclically, which coincides with results of research carried out in other countries. The fact that the momentum effect did not disappear may suggest that the factors involved in its creation are an indispensable part of the market, and this seems to undermine the commonly accepted

  4. Age-related and stand-wise estimates of carbon stocks and sequestration in the aboveground coarse wood biomass of wetland forests in the northern Pantanal, Brazil

    Science.gov (United States)

    Schöngart, J.; Arieira, J.; Felfili Fortes, C.; Cezarine de Arruda, E.; Nunes da Cunha, C.

    2011-11-01

    In this study we use allometric models combined with tree ring analysis to estimate carbon stocks and sequestration in the aboveground coarse wood biomass (AGWB) of wetland forests in the Pantanal, located in central South America. In four 1-ha plots in stands characterized by the pioneer tree species Vochysia divergens Pohl (Vochysiaceae) forest inventories (trees ≥10 cm diameter at breast height, D) have been performed and converted to estimates of AGWB by two allometric models using three independent parameters (D, tree height H and wood density ρ). We perform a propagation of measurement errors to estimate uncertainties in the estimates of AGWB. Carbon stocks of AGWB vary from 7.8 ± 1.5 to 97.2 ± 14.4 Mg C ha-1 between the four stands. From models relating tree ages determined by dendrochronological techniques to C-stocks in AGWB we derived estimates for C-sequestration which differs from 0.50 ± 0.03 to 3.34 ± 0.31 Mg C ha-1 yr-1. Maps based on geostatistic techniques indicate the heterogeneous spatial distribution of tree ages and C-stocks of the four studied stands. This distribution is the result of forest dynamics due to the colonizing and retreating of V. divergens and other species associated with pluriannual wet and dry episodes in the Pantanal, respectively. Such information is essential for the management of the cultural landscape of the Pantanal wetlands.

  5. Clean energy firms’ stock prices, technology, oil prices, and carbon price

    OpenAIRE

    Mara Madaleno; Alfredo Marvão Pereira

    2015-01-01

    Production costs of alternative energies are still high, but increased demand for oil, future oil supply shortage concerns and climate change concerns, have led to the fast development of renewable energy firms. The sector accomplished has accomplished remarkable progress and attracted attention to clean energy, both at the industry level and at the academic side. With this work we attempt to determine whether or not the placement of a price on carbon emissions encourages investments in clean...

  6. Long-Term Effects of Cover Crops on Crop Yields, Soil Organic Carbon Stocks and Sequestration

    OpenAIRE

    Kenneth Olson; Stephen A. Ebelhar; Lang, James M.

    2014-01-01

    A 12-year cover crops study on the effects on SOC sequestration, storage, retention and loss and corn and soybean yields was conducted in southern Illinois. The use of cover crops for the maintenance and restoration of soil organic carbon (SOC) and soil productivity of previously eroded soils were evaluated. No-till (NT), chisel plow (CP), and moldboard plow (MP) treatment plots with and without cover crops were established in 2001. The plot area was on sloping with a ...

  7. Trends in carbon stocks in Dutch soils: datasets and modeling results

    OpenAIRE

    Chardon, W.J.; Heesmans, H.I.M.; Kuikman, P.J.

    2009-01-01

    Observations on trends in soil organic carbon (SOC) in agricultural soils is an important basis for mandatory reporting of emission of greenhouse gases from land use. A decrease indicates that these soils are a source of CO2, an increase that they are a sink. IPCC Good Practice Guidance generally assumes that the SOC content of agricultural soils decreases. We evaluated large datasets on trends in SOC in the Netherlands and compared them with datasets from Belgium, England and with literature...

  8. Changes in forest biomass carbon stock in Northern Turkey between 1973 and 2006.

    Science.gov (United States)

    Misir, Mehmet

    2013-10-01

    New forest management and planning approaches are designed to optimize forest structure. Optimal forest structure was determined using newly established growth models while considering primary timber production objectives as well as non-timber objectives for inaccessible areas and social and political pressures on land management. With currently planned management the forests of the Ormanüstü Planning Unit (OPU) in the Black Sea region of northern Turkey are likely to become an important C sink. To quantify this potential C sink and understand its implication to the regional carbon budget and future forest management, we estimated the changes in the OPU between 1973 and 2006. Based on four periods of data for the OPU forests obtained from the Forest Management and Planning Office of Turkey, we used allometric biomass and C regression equations along with biomass expansion factors to estimate the forest biomass carbon pool for each of four inventory years 1973, 1984, 1997, and 2006. Since 1973, OPU forests have accumulated 110.2 × 10(3) tons of C as a result of forest expansion and the growth of extant forests, increasing by 50.8 % from 217 × 10(3) tons in 1973 to 327.2 × 10(3) tons C in 2006. Hardwood and softwood forests accounted for 44 and 56 % of carbon accumulation during this period, respectively. From 1973 through 2006, forest C accumulated at a rate of 3.3 × 10(3) tons C year(-1). Carbon density of the OPU forests in the Black Sea region increased by 48.2 % from 5,679 to 8,419 tons/ha. PMID:23564412

  9. Pension investments in employer stock

    OpenAIRE

    Even, William E.; David A. MacPherson

    2006-01-01

    This study examines the consequences of a pension fund investing in the stock of the sponsoring firm. Using a merger of data on pension asset holdings from IRS Form 5500 filings and financial data on the company's stock from CRSP, two broad questions are addressed: First, what factors influence the extent of a pension fund's investments in the employer's stock? Second, when a pension invests in the employer's stock, how much is lost as a result of poor diversification? The empirical results s...

  10. Modeling soil organic carbon stock after 10 years of cover crops in Mediterranean vineyards: improving ANN prediction by digital terrain analysis.

    Science.gov (United States)

    Lo Papa, Giuseppe; Novara, Agata; Santoro, Antonino; Gristina, Luciano

    2014-05-01

    Estimate changes in soil organic carbon (SOC) stock after Agro Environment Measures adoption are strategically for national and regional scale. Uncertainty in estimates also represents a very important parameter in terms of evaluation of the exact costs and agro environment payments to farmers. In this study we modeled the variation of SOC stock after 10-year cover crop adoption in a vine growing area of South-Eastern Sicily. A paired-site approach was chosen to study the difference in SOC stocks. A total 100 paired sites (i.e. two adjacent plots) were chosen and three soil samples (Ap soil horizons, circa 0-30 cm depth) were collected in each plot to obtain a mean value of organic carbon concentration for each plot. The variation of soil organic carbon (SOCv) for each plot was calculated by differences between concentrations of the plot subjected to cover crops (SOC10) and the relative plot subjected to traditional agronomic practices (SOC0). The feasibility of using artificial neural networks as a method to predict soil organic carbon stock variation and the contribution of digital terrain analysis to improve the prediction were tested. We randomly subdivided the experimental values of SOC-stock difference in 80 learning samples and 20 test samples for model validation. SOCv was strongly correlated to the SOC0 concentration. Model validation using only SOCv as unique covariate showed a training and test perfection of 0.724 and 0.871 respectively. We hypothesized that terrain-driven hydrological flow patterns, mass-movement and local micro-climatic factors could be responsible processes contributing for SOC redistributions, thus affecting soil carbon stock in time. Terrain attributes were derived by digital terrain analysis from the 10 m DEM of the study area. A total of 37 terrain attributes were calculated and submitted to statistical feature selection. The Chi-square ranking indicated only 4 significant covariates among the terrain attributes (slope height

  11. Effect of Terrain Characteristics on Soil Organic Carbon and Total Nitrogen Stocks in Soils of Herschel Island, Western Canadian Arctic

    OpenAIRE

    Obu, Jaroslav; Lantuit, Hugues; Myers-Smith, Isla; Heim, Birgit; Wolter, Juliane; Fritz, Michael

    2015-01-01

    Permafrost landscapes experience different disturbances and store large amounts of organic matter, which may become a source of greenhouse gases upon permafrost degradation. We analysed the influence of terrain and geomorphic disturbances (e.g. soil creep, active-layer detachment, gullying, thaw slumping, accumulation of fluvial deposits) on soil organic carbon (SOC) and total nitrogen (TN) storage using 11 permafrost cores from Herschel Island, western Canadian Arctic. Our results indicate a...

  12. Carbon Stocks and Climate Change: Management Implications in Northern Arizona Ponderosa Pine Forests

    Directory of Open Access Journals (Sweden)

    Benjamin Bagdon

    2014-04-01

    Full Text Available Researchers have observed climate-driven shifts of forest types to higher elevations in the Southwestern US and predict further migration coupled with large-scale mortality events proportional to increases in radiative forcing. Range contractions of forests are likely to impact the total carbon stored within a stand. This study examines the dynamics of Pinus ponderosa stands under three climate change scenarios in Northern Arizona using the Climate Forest Vegetation Simulator (Climate-FVS model to project changes in carbon pools. A sample of 90 stands were grouped according to three elevational ranges; low- (1951 to 2194 m, mid- (2194 to 2499 m, and high- (2499 to 2682 m. elevation stands. Growth, mortality, and carbon stores were simulated in the Climate-FVS over a 100 year timespan. We further simulated three management scenarios for each elevational gradient and climate scenario. Management included (1 a no-management scenario, (2 an intensive-management scenario characterized by thinning from below to a residual basal area (BA of 18 m2/ha in conjunction with a prescribed burn every 10 years, and (3 a moderate-management scenario characterized by a thin-from-below treatment to a residual BA of 28 m2/ha coupled with a prescribed burn every 20 years. Results indicate that any increase in aridity due to climate change will produce substantial mortality throughout the elevational range of ponderosa pine stands, with lower elevation stands projected to experience the most devastating effects. Management was only effective for the intensive-management scenario; stands receiving this treatment schedule maintained moderately consistent levels of basal area and demonstrated a higher level of resilience to climate change relative to the two other management scenarios. The results of this study indicate that management can improve resiliency to climate change, however, resource managers may need to employ more intensive thinning treatments than

  13. Widespread Tree Mortality from the 2011 Texas Drought: Consequences for Forest Structure and Carbon Stocks

    Science.gov (United States)

    Moore, G. W.; Edgar, C.; Vogel, J. G.; Washington-Allen, R. A.; March, R.; Zehnder, R.

    2013-12-01

    Larger and more frequent drought-related tree mortality events can alter the carbon cycling of terrestrial ecosystems; however, the carbon cycling implications of drought in forest ecosystems is poorly understood because the effects are not discrete in time, tree species have varying survival tolerances, and tree mortality from drought is often diffusely distributed across the landscape masking its effect from satellite observation. Widespread tree mortality was caused by the exceptional 2011 drought in Texas. In the summer following the drought, we used a statewide survey of 599 plots and satellite imagery (pre/post drought) to estimate the impact of the 2011 Texas Drought on forest C storage and cycling. In each 0.16 ha plot, dead trees were identified to the genus level and diameters were recorded. Normalized Difference Vegetation Index (ΔNDVI = May 2012 NDVI - May 2011 NDVI) derived from the MODIS satellite sensor was calibrated to the field plots to produce a 2011 tree mortality map for Texas. We estimate that 301 million trees died in Texas from the exceptional drought of 2011 (6.2% of live trees), which resulted in a conversion of 24-30 Tg C from live to dead tree carbon pools. This event was notable in that it affected a wide assemblage of species throughout the state across distinct ecoregions. The largest trees experienced disproportionately higher mortality; large angiosperms from historically wetter regions suffered the greatest losses. Gymnosperms thought to be drought-hardy also experienced unexpectedly high levels of mortality, with significant regional variation in whether the mortality was concentrated in large trees. The concentration of mortality in large trees likely had a disproportionate effect on forest net primary productivity, which is a key constraint on estimating the full effect of this drought on future forest C capture. In an effort toward full accounting of this event, we modeled its cumulative effects on regional C cycling and

  14. Spatially-Resolved Influence of Temperature and Salinity on Stock and Recruitment Variability of Commercially Important Fishes in the North Sea.

    Science.gov (United States)

    Akimova, Anna; Núñez-Riboni, Ismael; Kempf, Alexander; Taylor, Marc H

    2016-01-01

    Understanding of the processes affecting recruitment of commercially important fish species is one of the major challenges in fisheries science. Towards this aim, we investigated the relation between North Sea hydrography (temperature and salinity) and fish stock variables (recruitment, spawning stock biomass and pre-recruitment survival index) for 9 commercially important fishes using spatially-resolved cross-correlation analysis. We used high-resolution (0.2° × 0.2°) hydrographic data fields matching the maximal temporal extent of the fish population assessments (1948-2013). Our approach allowed for the identification of regions in the North Sea where environmental variables seem to be more influential on the fish stocks, as well as the regions of a lesser or nil influence. Our results confirmed previously demonstrated negative correlations between temperature and recruitment of cod and plaice and identified regions of the strongest correlations (German Bight for plaice and north-western North Sea for cod). We also revealed a positive correlation between herring spawning stock biomass and temperature in the Orkney-Shetland area, as well as a negative correlation between sole pre-recruitment survival index and temperature in the German Bight. A strong positive correlation between sprat stock variables and salinity in the central North Sea was also found. To our knowledge the results concerning correlations between North Sea hydrography and stocks' dynamics of herring, sole and sprat are novel. The new information about spatial distribution of the correlation provides an additional help to identify mechanisms underlying these correlations. As an illustration of the utility of these results for fishery management, an example is provided that incorporates the identified environmental covariates in stock-recruitment models. PMID:27584155

  15. Influence of stocking density on growth, body composition and energy budget of Atlantic salmon Salmo salar L. in recirculating aquaculture systems

    Science.gov (United States)

    Liu, Baoliang; Liu, Ying; Liu, Ziyi; Qiu, Denggao; Sun, Guoxiang; Li, Xian

    2014-09-01

    Atlantic salmon Salmo salar were reared at four stocking densities—high density D 1 (final density ˜39 kg/m3), medium densities D 2 (˜29 kg/m3) and D 3 (˜19 kg/m3), and low density D 4 (˜12 kg/m3)—for 40 days to investigate the effect of stocking density on their growth performance, body composition and energy budgets. Stocking density did not significantly affect specific growth rate in terms of weight (SGRw) but did affect specific growth rate in terms of energy (SGRe). Stocking density significantly influenced the ration level (RLw and RLe), feed conversion ratio (FCRw and FCRe) and apparent digestibility rate (ADR). Ration level and FCRw tended to increase with increasing density. Fish at the highest density D 1 and lowest density D 4 showed lower FCRe and higher ADR than at medium densities. Stocking density significantly affected protein and energy contents of the body but did not affect its moisture, lipid, or ash contents. The expenditure of energy for metabolism in the low-density and high-density groups was lower than that in the medium-density groups. Stocking density affected energy utilization from the feces but had no effect on excretion rate. The greater energy allocation to growth at high density and low density may be attributed to reduced metabolic rate and increased apparent digestibility rate. These findings provide information that will assist selection of suitable stocking densities in the Atlantic-salmon-farming industry.

  16. The Inventory of Forest Carbon Stocks in the Province of Trento: some remarks on the sampling design and first comments on its results

    OpenAIRE

    Gasparini P; Tabacchi G

    2008-01-01

    Multiple sampling designs are commonly used in forest inventory to combine information collected in very large first-phase samples using remote sensing (satelite or aerial images) with the field data collected on smaller sub-samples. In Italy, during the seventies, double sampling designs were used in some regional forest inventories and, later, multiple sampling was adopted for the second National Forest Inventory and for the Inventory of Forest Carbon Stocks (InFoCarb) in the Province of Tr...

  17. Effects of tree species, stand age and land-use change on soil carbon and nitrogen stock rates in northwestern Turkey

    OpenAIRE

    Sariyildiz T; Savaci G; Kravkaz IS

    2016-01-01

    Effects of tree species, stand age and land-use change on soil carbon and nitrogen stock rates were investigated in the northwest of Turkey using 4 common tree species as black pine (Pinus nigra Arnold.), Scots pine (Pinus sylvestris L.), Oriental beech (Fagus orientalis Lipsky) and Uludag fir (Abies nordmanniana ssp. bornmuelleriana). Three tree species (black pine, Scots pine and Oriental beech) were used to investigate the differences in soil C and N among tree species. Old and young Uluda...

  18. Remote Sensing of The Carbon Stocks of the UNESCO World Heritage Site: Mt. Apo Natural Park, Philippines

    Science.gov (United States)

    Washington-Allen, R. A.; Rubas, L. C.; Conner, J. R.; Delgado, A.; Popescu, S. C.

    2013-12-01

    Tropical forest cover has reduced to 20% of the Philippines (6.1 M ha) by 1996 from 90% or 27 M ha in the 16th century. Land use is a major cause of deforestation including shifting cultivation, permanent agriculture, ranching, logging, fuel-wood gathering and charcoal-making. The UN's Reduction of Emissions from Deforestation and Degradation Program's (REDD) Tier 1 evaluation of the Philippines estimates that between 0.8 to 2.5 Pg C are emitted per year with high uncertainty levels. The purpose of this study was to reduce this uncertainty by implementing a Tier 3 high resolution field and satellite remote sensing approach to assess above-ground forest carbon stocks over time in the 54,975 ha UNESCO World Heritage site: Mt. Apo Natural Park (MANP) in Mindanao Island, Philippines. We established approximately 25 30-m X 30-m pixel resolution tree stands in MANP measuring species diversity, composition, height, crown area, and diameter-at-breast height (dbh) both manually and with a terrestrial laser scanner (TLS). Both these data were used to calibrate the tree heights of 2000 Shuttle Radar Topography Mission (SRTM) 90-m C-band and 2004 Intermap 5-m X-band IFSAR, and 2009 30-m ASTER Global digital elevation model (GDEM) digital surface models (DSM). The 5-m IFSAR also includes a 5-m last return DEM, where DSM - DEM = Tree Height. A tree density map was derived using a minima-maxima convolution filter in conjunction with a land cover map developed by the Philippines Department of Environment and Natural Resources (DENR). A 'universal allometric equation' for tropical forests that inputs crown diameter and tree height was then used to generate both Tropical forest biomass and forest carbon maps of MANP.

  19. Characterizing forest carbon stocks at tropical biome and landscape level in Mount Apo National Park, Philippines

    Science.gov (United States)

    Rubas, L. C.

    2012-12-01

    Forest resources sequester and store carbon, and serve as a natural brake on climate change. In the tropics, the largest source of greenhouse emission is from deforestation and forest degradation (Gibbs et al 2007). This paper attempts to compile sixty (60) existing studies on using remote sensing to measure key environmental forest indicators at two levels of scales: biome and landscape level. At the tropical forest biome level, there is not as much remote sensing studies that have been done as compared to other forest biomes. Also, existing studies on tropical Asia is still sparse compared to other tropical regions in Latin America and Africa. Biomass map is also produced for the tropical biome using keyhole macro language (KML) which is projected on Google Earth. The compiled studies showed there are four indicators being measured using remote sensors in tropical forest. These are biomass, landcover classification, deforestation and cloud cover. The landscape level will focus on Mount Apo National Park in the Philippines which is encompassing a total area of 54,974.87 hectares. It is one of the ten priority sites targeted in the World Bank-assisted Biodiversity Conservation Program. This park serves as the major watershed for the three provinces with 19 major rivers emanating from the montane formations. Only a small fraction of the natural forest that once covered the country remains. In spite of different policies that aim to reduce logging recent commercial deforestation, illegal logging and agricultural expansion pose an important threat to the remaining forest areas. In some locations in the country, these hotspots of deforestation overlap with the protected areas (Verburg et al 2006). The study site was clipped using ArcGIS from the forest biomass carbon density map produced by Gibbs and Brown (2007). Characterization on this national park using vegetation density, elevation, slope, land cover and precipitation will be conducted to determine factors that

  20. A simplified modelling approach for quantifying tillage effects on soil carbon stocks

    DEFF Research Database (Denmark)

    Chatskikh, Dmitri; Hansen, Søren; Olesen, Jørgen E.;

    2009-01-01

    Soil tillage has been shown to affect long-term changes in soil organic carbon (SOC) content in a number of field experiments. This paper presents a simplified approach for including effects of tillage in models of soil C turnover in the tilled-soil layer. We used an existing soil organic matter...... (SOM) model (CN-SIM) with standard SOC data for a homogeneous tilled layer from four long-term field experiments with conventionally tilled (CT) and no-till (NT) treatments. The SOM model was tested on data from long-term (>10 years) field trials differing in climatic conditions, soil properties......, residue management and crop rotations in Australia, Brazil, the USA and Switzerland. The C input for the treatments was estimated using data on crop rotation and residue management. The SOM model was applied for both CT and NT trials without recalibration, but incorporated a 'tillage factor' (TF) to scale...

  1. Stock Status

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data inform the public of the most recent stock status for all stocks (FSSI and non-FSSI) in the fishery management unit contained in a fishery managment...

  2. Heterogeneous Stock Rat: A Unique Animal Model for Mapping Genes Influencing Bone Fragility

    OpenAIRE

    Alam, Imranul; Koller, Daniel L; Sun, Qiwei; Roeder, Ryan K.; Cañete, Toni; Blázquez, Gloria; López-Aumatell, Regina; Martínez-Membrives, Esther; Vicens-Costa, Elia; Mont, Carme; Díaz, Sira; Tobeña, Adolf; Fernández-Teruel, Alberto; Whitley, Adam; Strid, Pernilla

    2011-01-01

    Previously, we demonstrated that skeletal mass, structure and biomechanical properties vary considerably among 11 different inbred rat strains. Subsequently, we performed quantitative trait loci (QTL) analysis in 4 inbred rat strains (F344, LEW, COP and DA) for different bone phenotypes and identified several candidate genes influencing various bone traits. The standard approach to narrowing QTL intervals down to a few candidate genes typically employs the generation of congenic lines, which ...

  3. Improving Soil Organic Carbon stock estimates in agricultural topsoil at a regional scale using a Stochastic Gradient Boosting technique

    Science.gov (United States)

    Schillaci, Calogero; Lombardo, Luigi; Saia, Sergio; Fantappiè, Maria; Märker, Michael; Acutis, Marco

    2016-04-01

    Agro-ecosystems have a paramount importance as a source of goods and incomes and have a highly unexpressed potential to mitigate greenhouse gasses (GHG) emission. In agro-ecosystems, Soil Organic Carbon (SOC) is recognized as the most important trait to be managed in order to maintain soil fertility and ecosystems services. Accurate laboratory analysis is indeed the best way to investigate soils. However, it is expensive and time consuming when aiming at gaining information on large areas such as an entire district or region. Remote Sensing (RS) is recently offering increasingly detailed Digital Elevation Models (DEMs) and low-cost multispectral satellite imagery. Moreover accurate worldwide climate records of the last 50 years were recently made freely available. Across Sicily, there is a strong heterogeneity of agro-ecosystems, with a dominance of field crops and orchards. In the present work, we modeled the SOC through a wide range of predictors including both ecosystem and agronomic characteristics of the soils, such as panchromatic bands, a Normalized Differenced Vegetation Index NDVI and landuse based on multispectral remote-sensed data LANDSAT ETM+7, terrain attributes derived by radar satellite data from the Shuttle Radar Topographic Mission (SRTM), as well as soil texture information and climate data record from WORLDCLIM. As dependent variable, a set of 2,891 Walkley-Black SOC and 1,049 bulk density laboratory analyses collected throughout Sicily (Italy) was used for modelling the CS stock and build the map. The Stochastic Gradient Treeboost (SGT) learning algorithm was applied to 75% of the CS stock dataset. The remaining 25% was used to validate the model. In addition, the SGT was compared to a Generalized Linear Mixed Model (GLMM). Both SGT and GLMM models show a high performance. With regards to the full model, both algorithms designated temperature and annual rainfall as fundamental predictors of CS. In addition, SGT highlighted the annual rainfall

  4. Influence of public transport in black carbon

    Science.gov (United States)

    Vasquez, Y.; Oyola, P.; Gramsch, E. V.; Moreno, F.; Rubio, M.

    2013-05-01

    As a consequence of poor air quality in Santiago de Chile, several measures were taken by the local authorities to improve the environmental conditions and protect the public health. In year 2005 the Chilean government implemented a project called "Transantiago" aimed to introduce major modifications in the public transportation system. The primary objectives of this project were to: provide an economically, socially and environmentally sustainable service and improve the quality of service without increasing fares. In this work we evaluate the impact of the Transantiago system on the black carbon pollution along four roads directly affected by the modification to the transport system. The black carbon has been used to evaluate changes in air quality due to changes in traffic. The assessment was done using measurements of black carbon before Transantiago (June-July 2005) and after its implementation (June-July 2007). Four sites were selected to monitor black carbon at street levels, one site (Alameda) that represents trunk-bus streets, i.e., buses crossing the city through main avenues. Buses using these streets had an important technological update with respect to 2005. Two streets (Usach and Departamental) show a mixed condition, i.e., they combine feeder and trunk buses. These streets combine new EURO III buses with old buses with more than 3 years of service. The last street (Eliodoro Yañez) represent private cars road without public transportation and did not experience change. Hence, the results from the years 2005 and 2007 can be directly compared using an appropriate methodology. To ensure that it was not the meteorological conditions that drive the trends, the comparison between year 2005 and 2007 was done using Wilcoxon test and a regression model. A first assessment at the four sites suggested a non decrease in black carbon concentration from 2005 to 2007, except for Alameda. A first statistical approach confirmed small increases in BC in Usach and E

  5. Mechanisms of soil degradation and consequences for carbon stocks on Tibetan grasslands

    Science.gov (United States)

    Kuzyakov, Yakov; Schleuss, Per-Marten; Miehe, Georg; Heitkamp, Felix; Sebeer, Elke; Spielvogel, Sandra; Xu, Xingliang; Guggenberger, Georg

    2016-04-01

    Tibetan grasslands provide tremendous sinks for carbon (C) and represent important grazing ground. Strong degradation - the destroying the upper root-mat/soil horizon of Kobresia pastures, has dramatic consequences for soil organic carbon (SOC) and nutrient storage. To demonstrate specific degradation patterns and elucidate mechanisms, as well as to assess consequences for SOC storage, we investigated a sequence of six degradation stages common over the whole Kobresia ecosystem. The soil degradation sequence consists of following mechanisms: Overgrazing and trampling by livestock provide the prerequisite for grassland degradation as both (a) cause plant dying, (b) reduce grassland recovery and (c) destroy protective Kobresia root-mats. These anthropogenic induced processes are amplified by naturally occurring degradation in harsh climate. The frequently repeated soil moisture and temperature fluctuations induce volume changes and tensions leading to polygonal cracking of the root mats. Then the plants die and erosion gradually extend the surface cracks. Soil erosion cause a high SOC loss from the upper horizons (0-10 cm: ~5.1 kg C m-2), whereas SOC loss beneath the surface cracks is caused by both, decreasing root C-input and SOC mineralization (SOC losses by mineralization: ~2.5 kg C m-2). Root biomass decreases with degradation and indicated lower C input. The negative δ13C shift of SOC reflects intensive decomposition and corresponds to a relative enrichment of 13C depleted lignin components. We conclude that the combined effects of overgrazing and harsh climate reduce root C input, increase SOC decomposition and initiate erosion leading to SOC loss up to 70% of intact soil (0-30 cm: ~7.6 kg C m-2). Consequently, a high amount of C is released back to the atmosphere as CO2, or is deposited in depressions and river beds creating a potential source of N2O and CH4. Concluding, anthropogenically induced overgrazing makes the Kobresia root-mat sensitive to natural

  6. Distribution of individual inbreeding coefficients, relatedness and influence of stocking on native anadromous brown trout ( Salmo trutta ) population structure

    DEFF Research Database (Denmark)

    Ruzzante, D.E.; Hansen, Michael Møller; Meldrup, Dorte

    2001-01-01

    We examined polymorphism at seven microsatellite loci in 4023 brown trout (Salmo trutta) collected from 32 tributaries to the Limfjord, Denmark (similar to 200 km) and from two hatcheries used for stocking. Populations differ in their estimated sizes and stocking histories. Mean individual...

  7. Use of microsatellite markers for identification of indigenous brown trout in a geographical region heavily influenced by stocked domesticated trout

    DEFF Research Database (Denmark)

    Fritzner, Niels G.; Møller Hansen, Michael; Madsen, Steffen;

    2001-01-01

    Based on estimates of genetic differentiation between populations, assignment tests and analysis of isolation by distance, stocked populations of brown trout Salmo trutta of Funen Island, Denmark, had been genetically affected by domesticated trout, whereas the stocking of wild exogenous trout into...

  8. Improving estimation of tree carbon stocks by harvesting aboveground woody biomass within airborne LiDAR flight areas

    Science.gov (United States)

    Colgan, M.; Asner, G. P.; Swemmer, A. M.

    2011-12-01

    The accurate estimation of carbon stored in a tree is essential to accounting for the carbon emissions due to deforestation and degradation. Airborne LiDAR (Light Detection and Ranging) has been successful in estimating aboveground carbon density (ACD) by correlating airborne metrics, such as canopy height, to field-estimated biomass. This latter step is reliant on field allometry which is applied to forest inventory quantities, such as stem diameter and height, to predict the biomass of a given tree stem. Constructing such allometry is expensive, time consuming, and requires destructive sampling. Consequently, the sample sizes used to construct such allometry are often small, and the largest tree sampled is often much smaller than the largest in the forest population. The uncertainty resulting from these sampling errors can lead to severe biases when the allometry is applied to stems larger than those harvested to construct the allometry, which is then subsequently propagated to airborne ACD estimates. The Kruger National Park (KNP) mission of maintaining biodiversity coincides with preserving ecosystem carbon stocks. However, one hurdle to accurately quantifying carbon density in savannas is that small stems are typically harvested to construct woody biomass allometry, yet they are not representative of Kruger's distribution of biomass. Consequently, these equations inadequately capture large tree variation in sapwood/hardwood composition, root/shoot/leaf allocation, branch fall, and stem rot. This study eliminates the "middleman" of field allometry by directly measuring, or harvesting, tree biomass within the extent of airborne LiDAR. This enables comparisons of field and airborne ACD estimates, and also enables creation of new airborne algorithms to estimate biomass at the scale of individual trees. A field campaign was conducted at Pompey Silica Mine 5km outside Kruger National Park, South Africa, in Mar-Aug 2010 to harvest and weigh tree mass. Since

  9. Use of BIOME-BGG to simulate Mediterranean forest carbon stocks

    Directory of Open Access Journals (Sweden)

    Chirici G

    2011-06-01

    Full Text Available BIOME-BGC is a bio-geochemical model capable of estimating the water, carbon and nitrogen fluxes and storages of terrestrial ecosystems. Previous research demonstrated that, after proper calibration of its ecophysiological parameters, the model can reproduce the main processes of Mediterranean forest types. The same investigations, however, indicated a model tendency to overestimate woody biomass accumulation. The current paper aims at modifying BIOME-BGC ecophysiological settings to improve the simulation of the woody compartment in Mediterranean forests. The modified ecophysiological parameter is the whole-plant mortality fraction (WPMF, which directly affects the amount of woody biomass stored. The optimal WPMFs of six main forest types in Tuscany are identified by forcing the model to reproduce the maximum standing volumes found in regional and local forest inventories. The effects of this operation are evaluated by comparing the model outputs produced using the original and modified settings to independent measurements from national forest inventories. The results obtained demonstrate the effectiveness of the modifications introduced and consolidate the methodological basis for extending the use of the modeling strategy to other Mediterranean areas.

  10. Allometric Equations for Estimating Carbon Stocks in Natural Forest in New Zealand

    Directory of Open Access Journals (Sweden)

    Andrea Brandon

    2012-09-01

    Full Text Available Species-specific and mixed-species volume and above ground biomass allometric equations were developed for 15 indigenous tree species and four tree fern species in New Zealand. A mixed-species tree equation based on breast height diameter (DBH and tree height (H provided acceptable estimates of stem plus branch (>10 cm in diameter over bark volume, which was multiplied by live tree density to estimate dry matter. For dead standing spars, DBH, estimated original height, actual spar height and compatible volume/taper functions provided estimates of dead stem volume, which was multiplied by live tree density and a density modifier based on log decay class from field assessments to estimate dry matter. Live tree density was estimated using ratio estimators. Ratio estimators were based on biomass sample trees, and utilized density data from outerwood basic density surveys which were available for 35 tree species sampled throughout New Zealand. Foliage and branch ( < 10 cm in diameter over bark dry matter were estimated directly from tree DBH. Tree fern above ground dry matter was estimated using allometric equations based on DBH and H. Due to insufficient data, below ground carbon for trees was estimated using the default IPCC root/shoot ratio of 25%, but for tree ferns it was estimated using measured root/shoot ratios which averaged 20%.

  11. Siberian tundra ecosystem vegetation and carbon stocks four decades after wildfire

    Science.gov (United States)

    Loranty, Michael M.; Natali, Susan M.; Berner, Logan T.; Goetz, Scott J.; Holmes, Robert M.; Davydov, Sergei P.; Zimov, Nikita S.; Zimov, Sergey A.

    2014-11-01

    Tundra ecosystem fire regimes are intensifying with important implications for regional and global carbon (C) and energy dynamics. Although a substantial portion of the tundra biome is located in Russia, the vast majority of accessible studies describe North American tundra fires. Here we use field observations and high-resolution satellite remote sensing observations to describe the effects of wildfire on ecosystem C pools and vegetation communities four decades after fire for a tundra ecosystem in northeastern Siberia. Our analyses reveal no differences between soil physical properties and C pools in burned and unburned tundra, which we attribute to low combustion of organic soil associated with low-severity fire. Field and remote sensing data show no differences in aboveground C pools and vegetation communities indicating recovery to prefire conditions. These results are comparable to observations of ecosystem recovery in North American tundra. An assessment of literature data indicate that the average annual area burned in Russian tundra is an order of magnitude larger than that of Alaskan tundra, highlighting a crucial need to assess Russian tundra fire regimes in order to understand the current and future role of the biome wide fire regime in regional and global C and energy dynamics.

  12. Improving the Spatial Prediction of Soil Organic Carbon Stocks in a Complex Tropical Mountain Landscape by Methodological Specifications in Machine Learning Approaches.

    Directory of Open Access Journals (Sweden)

    Mareike Ließ

    Full Text Available Tropical forests are significant carbon sinks and their soils' carbon storage potential is immense. However, little is known about the soil organic carbon (SOC stocks of tropical mountain areas whose complex soil-landscape and difficult accessibility pose a challenge to spatial analysis. The choice of methodology for spatial prediction is of high importance to improve the expected poor model results in case of low predictor-response correlations. Four aspects were considered to improve model performance in predicting SOC stocks of the organic layer of a tropical mountain forest landscape: Different spatial predictor settings, predictor selection strategies, various machine learning algorithms and model tuning. Five machine learning algorithms: random forests, artificial neural networks, multivariate adaptive regression splines, boosted regression trees and support vector machines were trained and tuned to predict SOC stocks from predictors derived from a digital elevation model and satellite image. Topographical predictors were calculated with a GIS search radius of 45 to 615 m. Finally, three predictor selection strategies were applied to the total set of 236 predictors. All machine learning algorithms-including the model tuning and predictor selection-were compared via five repetitions of a tenfold cross-validation. The boosted regression tree algorithm resulted in the overall best model. SOC stocks ranged between 0.2 to 17.7 kg m-2, displaying a huge variability with diffuse insolation and curvatures of different scale guiding the spatial pattern. Predictor selection and model tuning improved the models' predictive performance in all five machine learning algorithms. The rather low number of selected predictors favours forward compared to backward selection procedures. Choosing predictors due to their indiviual performance was vanquished by the two procedures which accounted for predictor interaction.

  13. Measuring the Role of Ecological Shift and Environmental Change on Organic Carbon Stocks in Salt Marshes and Mangrove Dominated Wetlands from the Texas Gulf Coast

    Science.gov (United States)

    Norwood, M. J.; Louchouarn, P.; Armitage, A. R.; HighField, W.; Brody, S.; White, N.

    2014-12-01

    Texas coastal wetlands are dynamic marsh-mangrove ecotones that play an important role in fishery recruitment, storm buffering, and carbon storage. Historically, C4 salt marsh plants, such as Spartina alterniflora, have dominated the Texas Gulf Coast. For the past 2-3 decades, some of these ecosystems have experienced community shifts with woody tropical plants (Avicennia germinans) competing for resources. This study presents new results on the carbon sequestration potential following such ecological shifts as well as coastal development and wetland loss along the coast of Texas. The recorded change from native grass-dominated C4 salt marshes to wood-dominated C3 mangroves over the last 20 years (1990-2010: 4,660 km2) leads to a non-significant loss in aboveground organic carbon (OC) stocks (-6.5.106 g OC). The most substantial loss of aboveground OC in Texas coastal salt marshes is due to the transformation of these wetlands into tidal flats and open water (-7.53.108 g OC). Similarly, the largest losses in aboveground OC stocks from mangrove ecosystems (-1.57.107 g OC) are due to replacement by open water. Along with the decrease in aboveground OC stocks, we identified a significant decrease in sedimentary OC inventories due to the loss of salt marsh and mangrove coverage (-3.69.109 g OC and 5.71.107 g OC, respectively). In contrast, mangrove expansion into mudflat and salt marsh environments led to a positive addition in aboveground OC stocks (2.78.108 g OC) and increased OC sedimentary inventories (2.32.109 g OC). Mangrove expansion offsets only 70% of the total calculated OC loss (-4.51.109 g OC) in coastal wetlands along the Texas gulf coast over the 20-year study period. This deficit loss is primarily attributed to environmental pressures on coastal salt marshes (i.e., sea level rise, urban and coastal development, erosion).

  14. An Improved Analysis onTrends and Uncertainties of Carbon Stocks and Fluxes in the Piedmont Ecoregion of the United States Using Data Assimilation

    Science.gov (United States)

    Chen, M.; Liu, S.; Young, C.; Tieszen, L. L.

    2011-12-01

    Accurate quantification of carbon fluxes and stocks in the terrestrial ecoregions can improve our understanding of carbon sequestration processes and further help address global climate change issues. However, two current principal approaches, modeling and measuring, have inherent limitations that usually lead to uncertainties of quantification. Such limitations include poorly defined parameters, model input errors, and spatially patchy and multi-resolution characteristics of measurements. Advanced data assimilation techniques can mitigate these limitations by combining a series of measurements with dynamic models. In this study, we used a sequential data assimilation method, the Smoothed Ensemble Kalman Filter (SEnKF), to assimilate the data from various sources into the General Ensemble Biogeochemical Modeling System (GEMS). This method (1) optimally estimates trends of carbon fluxes and stocks in the Piedmont ecoregion of the United States from the 1970s to the 2000s, and (2) simultaneously constrains several key model parameters (e.g., maximum potential production) for various types of land covers for improving the model prediction. Assimilated data included gross primary production, net primary production, and leaf area index from the Moderate Resolution Imaging Spectroradiometer (MODIS), grain yields at the county level from the U.S. Department of Agriculture (USDA), and forest characteristics from the USDA Forest Service's Forest Inventory and Analysis database. Our preliminary analyses indicated that carbon sequestration in the Piedmont ecoregion gradually decreased in the past three decades, and the interannual variability was strongly affected by climate variability. Our approach reduced uncertainties in the estimated carbon fluxes and stocks in forests, croplands, and grasslands by 50 percent compared to the estimates using originally defined parameters.

  15. Resolving model parameter values from carbon and nitrogen stock measurements in a wide range of tropical mature forests using nonlinear inversion and regression trees

    Science.gov (United States)

    Liu, S.; Anderson, P.; Zhou, G.; Kauffman, B.; Hughes, F.; Schimel, D.; Watson, Vicente; Tosi, Joseph

    2008-01-01

    Objectively assessing the performance of a model and deriving model parameter values from observations are critical and challenging in landscape to regional modeling. In this paper, we applied a nonlinear inversion technique to calibrate the ecosystem model CENTURY against carbon (C) and nitrogen (N) stock measurements collected from 39 mature tropical forest sites in seven life zones in Costa Rica. Net primary productivity from the Moderate-Resolution Imaging Spectroradiometer (MODIS), C and N stocks in aboveground live biomass, litter, coarse woody debris (CWD), and in soils were used to calibrate the model. To investigate the resolution of available observations on the number of adjustable parameters, inversion was performed using nine setups of adjustable parameters. Statistics including observation sensitivity, parameter correlation coefficient, parameter sensitivity, and parameter confidence limits were used to evaluate the information content of observations, resolution of model parameters, and overall model performance. Results indicated that soil organic carbon content, soil nitrogen content, and total aboveground biomass carbon had the highest information contents, while measurements of carbon in litter and nitrogen in CWD contributed little to the parameter estimation processes. The available information could resolve the values of 2-4 parameters. Adjusting just one parameter resulted in under-fitting and unacceptable model performance, while adjusting five parameters simultaneously led to over-fitting. Results further indicated that the MODIS NPP values were compressed as compared with the spatial variability of net primary production (NPP) values inferred from inverse modeling. Using inverse modeling to infer NPP and other sensitive model parameters from C and N stock observations provides an opportunity to utilize data collected by national to regional forest inventory systems to reduce the uncertainties in the carbon cycle and generate valuable

  16. Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel

    2000-01-01

    Abstract Monitoring Techniques for Microbially Influenced Corrosion of Carbon Steel Microbially influenced corrosion (MIC) of carbon steel may occur in media with microbiological activity of especially sulphate-reducing bacteria, e.g. on pipelines buried in soil and on marine structures. MIC of...... carbon steel must be monitored on-line in order to provide an efficient protection and control the corrosion. A number of monitoring techniques is industrially used today, and the applicability and reliability of these for monitoring MIC is evaluated. Coupons and ER are recommended as necessary basic...... techniques even though localised corrosion rate cannot be measured. FSM measures general corrosion and detects localised corrosion, but the sensitivity is not high enough for monitoring initiation of pitting and small attacks. Electrochemical techniques as LPR and EIS give distorted data and unreliable...

  17. Influence of calving season and stocking rate on birth weight and weaning weight of Simmental-sired calves from Brahman-Hereford F1 dams.

    Science.gov (United States)

    Gaertner, S J; Rouquette, F M; Long, C R; Turner, J W

    1992-08-01

    Braham-Hereford F1 dams have been used to evaluate the influence of grazing pressure on forage attributes and animal performance at the Texas A&M University Agricultural Research Center at Overton. Data for this study were compiled from 1,909 records of Simmental-sired calves born to Braham-Hereford F1 cows from 1975 to 1990. Birth weight and weaning weight were analyzed independently to estimate the influence of year, season of birth, dam age, weaning age, and sex of calf. The effect of stocking rate as represented by levels of forage availability on weaning weights and subsequent birth weights was measured. Within the fall and winter calving seasons, lactating dams grazing at a high stocking rate produced calves with the lowest subsequent birth weights. Lactating dams assigned to creep-fed treatments had calves with the heaviest subsequent birth weights. Although dams that were less than 3.5 yr of age had calves with the lightest birth weights, there was no apparent decline in birth weight of calves from dams 12 to 17 yr old. Year, sex of calf, age of dam, stocking rate, season of birth, age at weaning, and birth weight were significant factors affecting weaning weight (P less than .01). Fall-born calves grazing cool-season annual pastures were heavier at weaning (267.6 kg) than either winter- (252.0 kg) or spring-born calves (240.9 kg). A stocking rate x season-of-birth interaction was observed for birth weight and weaning weight (P less than .05). Differences in weaning weight from low- vs high-stocked pastures were greater for fall-born calves (61.6 kg) than for winter-born calves (48.7).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1506293

  18. Accounting for density reduction and structural loss in standing dead trees: Implications for forest biomass and carbon stock estimates in the United States

    Directory of Open Access Journals (Sweden)

    Domke Grant M

    2011-11-01

    Full Text Available Abstract Background Standing dead trees are one component of forest ecosystem dead wood carbon (C pools, whose national stock is estimated by the U.S. as required by the United Nations Framework Convention on Climate Change. Historically, standing dead tree C has been estimated as a function of live tree growing stock volume in the U.S.'s National Greenhouse Gas Inventory. Initiated in 1998, the USDA Forest Service's Forest Inventory and Analysis program (responsible for compiling the Nation's forest C estimates began consistent nationwide sampling of standing dead trees, which may now supplant previous purely model-based approaches to standing dead biomass and C stock estimation. A substantial hurdle to estimating standing dead tree biomass and C attributes is that traditional estimation procedures are based on merchantability paradigms that may not reflect density reductions or structural loss due to decomposition common in standing dead trees. The goal of this study was to incorporate standing dead tree adjustments into the current estimation procedures and assess how biomass and C stocks change at multiple spatial scales. Results Accounting for decay and structural loss in standing dead trees significantly decreased tree- and plot-level C stock estimates (and subsequent C stocks by decay class and tree component. At a regional scale, incorporating adjustment factors decreased standing dead quaking aspen biomass estimates by almost 50 percent in the Lake States and Douglas-fir estimates by more than 36 percent in the Pacific Northwest. Conclusions Substantial overestimates of standing dead tree biomass and C stocks occur when one does not account for density reductions or structural loss. Forest inventory estimation procedures that are descended from merchantability standards may need to be revised toward a more holistic approach to determining standing dead tree biomass and C attributes (i.e., attributes of tree biomass outside of sawlog

  19. Carbon stocks in organic matter fractions as affected by land use and soil management, with emphasis on no-tillage effect

    Directory of Open Access Journals (Sweden)

    Bayer Cimélio

    2002-01-01

    Full Text Available Land use and soil management may affect both labile and humified soil organic matter (SOM fractions, but the magnitude of these changes is poorly known in subtropical environments. This study investigated effects of four land use and soil management systems (forest, native pasture, and conventional tillage and no-tillage in a wheat/soybean succession on (i total soil organic carbon (SOC stocks (0 to 250mm depth and on (ii carbon (C stocks in labile (coarse, light and humified (mineral-associated, humic substances SOM fractions (0 to 25mm depth, in a Hapludox soil from southern Brazil. In comparison to the adjacent forest site, conventionally tilled soil presented 36% (46.2Mg ha-1 less SOC in the 0 to 250mm depth and a widespread decrease in C stocks in all SOM fractions in the 0 to 25mm depth. The coarse (>53 mum and light (<1kg dm-3 SOM fractions were the most affected under no-tillage, showing 393% (1.22Mg C ha-1 and 289% (0.55Mg C ha-1 increases, respectively, in relation to conventional tillage. Similar results were observed for mineral-associated SOM and humic substance C pools (34% and 38% increases, respectively under no-tillage. Compared with labile SOM fraction results, the percentual increments on C stocks in humified fractions were smaller; but in absolute terms this C pool yielded the highest increases (3.06 and 2.95Mg C ha-1, respectively. These results showed that both labile and humified organic matter are better protected under the no-tillage system, and consequently less vulnerable to mineralization. Humified SOM stabilization process involving interactions with variable charge minerals is probably important in maintaining and restoring soil and environmental quality in tropical and subtropical regions.

  20. How will organic carbon stocks in mineral soils evolve under future climate? Global projections using RothC for a range of climate change scenarios

    Directory of Open Access Journals (Sweden)

    P. Gottschalk

    2012-08-01

    Full Text Available We use a soil carbon (C model (RothC, driven by a range of climate models for a range of climate scenarios to examine the impacts of future climate on global soil organic carbon (SOC stocks. The results suggest an overall global increase in SOC stocks by 2100 under all scenarios, but with a different extent of increase among the climate model and emissions scenarios. The impacts of projected land use changes are also simulated, but have relatively minor impacts at the global scale. Whether soils gain or lose SOC depends upon the balance between C inputs and decomposition. Changes in net primary production (NPP change C inputs to the soil, whilst decomposition usually increases under warmer temperatures, but can also be slowed by decreased soil moisture. Underlying the global trend of increasing SOC under future climate is a complex pattern of regional SOC change. SOC losses are projected to occur in northern latitudes where higher SOC decomposition rates due to higher temperatures are not balanced by increased NPP, whereas in tropical regions, NPP increases override losses due to higher SOC decomposition. The spatial heterogeneity in the response of SOC to changing climate shows how delicately balanced the competing gain and loss processes are, with subtle changes in temperature, moisture, soil type and land use, interacting to determine whether SOC increases or decreases in the future. Our results suggest that we should stop looking for a single answer regarding whether SOC stocks will increase or decrease under future climate, since there is no single answer. Instead, we should focus on improving our prediction of the factors that determine the size and direction of change, and the land management practices that can be implemented to protect and enhance SOC stocks.

  1. How will organic carbon stocks in mineral soils evolve under future climate? Global projections using RothC for a range of climate change scenarios

    Directory of Open Access Journals (Sweden)

    P. Gottschalk

    2012-01-01

    Full Text Available We use a soil carbon (C model (RothC, driven by a range of climate models for a range of climate scenarios to examine the impacts of future climate on global soil organic carbon (SOC stocks. The results suggest an overall global increase in global SOC stocks by 2100 under all scenarios, but with a different extent of increase among the climate model and emissions scenarios. Projected land use changes are also simulated, but have relatively small impacts at the global scale. Whether soils gain or lose SOC depends upon the balance between C inputs and decomposition. Changes in net primary production (NPP change C inputs to the soil, whilst decomposition usually increases under warmer temperatures, but can also be slowed by decreased soil moisture. Underlying the global trend of increasing SOC under future climate is a complex pattern of regional SOC change. SOC losses are projected to occur in northern latitudes where higher SOC decomposition rates due to higher temperatures are not balanced by increased NPP, whereas in tropical regions, NPP increases override losses due to higher SOC decomposition. The spatial heterogeneity in the response of SOC to changing climate shows how delicately balanced the competing gain and loss processes are, with subtle changes in temperature, moisture, soil type and land use, interacting to determine whether SOC increases or decreases in the future. Our results suggest that we should stop asking the general question of whether SOC stocks will increase or decrease under future climate since there is no single answer. Instead, we should focus on improving our prediction of the factors that determine the size and direction of change, and the land management practices that can be implemented to protect and enhance SOC stocks.

  2. Age-related and stand-wise estimates of carbon stocks and sequestration in the aboveground coarse wood biomass of wetland forests in the northern Pantanal, Brazil

    Directory of Open Access Journals (Sweden)

    J. Schöngart

    2011-11-01

    Full Text Available In this study we use allometric models combined with tree ring analysis to estimate carbon stocks and sequestration in the aboveground coarse wood biomass (AGWB of wetland forests in the Pantanal, located in central South America. In four 1-ha plots in stands characterized by the pioneer tree species Vochysia divergens Pohl (Vochysiaceae forest inventories (trees ≥10 cm diameter at breast height, D have been performed and converted to estimates of AGWB by two allometric models using three independent parameters (D, tree height H and wood density ρ. We perform a propagation of measurement errors to estimate uncertainties in the estimates of AGWB. Carbon stocks of AGWB vary from 7.8 ± 1.5 to 97.2 ± 14.4 Mg C ha−1 between the four stands. From models relating tree ages determined by dendrochronological techniques to C-stocks in AGWB we derived estimates for C-sequestration which differs from 0.50 ± 0.03 to 3.34 ± 0.31 Mg C ha−1 yr−1. Maps based on geostatistic techniques indicate the heterogeneous spatial distribution of tree ages and C-stocks of the four studied stands. This distribution is the result of forest dynamics due to the colonizing and retreating of V. divergens and other species associated with pluriannual wet and dry episodes in the Pantanal, respectively. Such information is essential for the management of the cultural landscape of the Pantanal wetlands.

  3. Distribution of individual inbreeding coefficients, relatedness and influence of stocking on native anadromous brown trout ( Salmo trutta ) population structure

    DEFF Research Database (Denmark)

    Ruzzante, D.E.; Hansen, Michael Møller; Meldrup, Dorte

    2001-01-01

    inbreeding coefficients do not differ among locations within rivers. Relatedness varies between sites within rivers indicating varied local dynamics at a very small geographical scale. Relatedness is sometimes lower than expected among an equal number of simulated individuals with randomized genotypes...... origin but this proportion varies regionally, with rivers in the western area of the Limfjord showing a relatively high (mean 88%) and those in the eastern area showing a relatively low (mean 72%) proportion of locally assigned trout. These results can be interpreted as reflecting stocking impact. Also......, the proportion of locally assigned trout correlates with the populations' stocking histories, with rivers presently subjected to stocking (hatchery trout) showing low mean similar to0.73), and rivers where stocking was discontinued showing high (mean similar to0.84) proportions of local fish, probably...

  4. Carbon stocks estimates for French forests. COST E21 Workshop. Contribution of forests and forestry to mitigate greenhouse effects. Joensuu (Finland. 28-30 Sep 2000

    Directory of Open Access Journals (Sweden)

    Dupouey J.L.

    2000-01-01

    Full Text Available This paper gives a short description of the data and methods used for inventorying the carbon stocks in the biomass and soil pools in metropolitan French forests. The data concerning the biomass pools are measured by the French National Forest Inventory (NFI while data necessary to estimate the soil carbon pools are obtained from the 16 x 16 km soil inventory of the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests in the UN/ECE. Some of the problems raised by the implementation of the Kyoto protocol articles 3.3 and 3.4 in France are discussed and a preliminary estimate of the changes in relevant carbon storage is given.