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Problems in the inventory of the belowground forest biomass carbon stocks
Lasserre B,Marchetti M,Tognetti R
Forest@ , 2006,
Abstract: Signatory countries of Kyoto Protocol are engaged in carrying out national inventories to quantify greenhouse gas emission and potentiality of C sinks. Forests represent the terrestrial ecosystem with the highest C sequestration capacity taking up CO2 from the atmosphere and fixing it in vegetal biomass through photosynthesis process; C stocks can be divided in aboveground and belowground ones. In inventorial processes, root biomass is empirically extrapolated from aboveground biomass using a 0.2 factor, which underestimate the real value. Some authors suggest that total underground C allocation can be assessed from the difference between annual respiration rate and litter fall. Belowground biomass can be divided in permanent biomass (structural roots) and temporary one (fine roots). Models allow a valuation of structural roots biomass from stand dendrometrical characteristics. Literature reveals that underground biomass, as fine roots than structural ones, highly varies with local conditions. The development of models that take into account these station parameters and therefore able to reproduce this variability seems to be obligatory to deal with inventory processes with an acceptable precision.
Estimation of biomass and carbon stocks: the case of the Atlantic Forest
Vieira, Simone Aparecida;Alves, Luciana Ferreira;Aidar, Marcos;Araújo, Luciana Spinelli;Baker, Tim;Batista, Jo?o Luís 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;Mattos, Eduardo Arcoverde de;Metzker, Thiago;Phillips, Oliver;Santos, Flavio Antonio Maes dos;Shimabukuro, M?nica Takako;Silveira, Marcos;Trumbore, Susan Elizabeth;
Biota Neotropica , 2008, DOI: 10.1590/S1676-06032008000200001
Abstract: 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 unit volume of fresh wood). it can be quantified by the direct (destructive) or indirect method where the biomass quantification is estimated using mathematical models. the allometric model can be site specific when elaborated to a particular ecosystem or general that can be used in different sites. for the atlantic forest, despite the importance of it, there are only two direct measurements of tree biomass, resulting in allometric models specific for this ecosystem. to select one or other of the available models in the literature to estimate agb it is necessary take into account what is the main question to be answered and the ease with which it is possible to measure the independent variables in the model. models that present more accurate estimates should be preferred. however, more simple models (those with one independent variable, usually dbh) can be used when the focus is monitoring the variation in carbon storage through the time. our observations in the atlantic forest suggest that pan-tropical relations proposed by chave et al. (2005) can be confidently used to estimated tree biomass across biomes as long as tree diameter (dbh), height, and wood density are accounted for in the model. in atlantic forest, we recommend the quantification of biomass of lianas, bamboo, palms, tree ferns and epiphytes, which are an important component in this ecosystem. this paper is an outcome of the workshop entitled "estimation of biomass and carbon stocks: the case of atlantic rain fore
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
J. Sch ngart, J. Arieira, C. Felfili Fortes, E. Cezarine de Arruda,C. Nunes da Cunha
Biogeosciences (BG) & Discussions (BGD) , 2011,
Abstract: 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.
Application of Remote Sensing and Developed Allometric Models for Estimating Wood Carbon Stocks in a North-Western Miombo Woodland Landscape of Tanzania  [PDF]
Geofrey Soka,Nanjiva Nzunda
Journal of Ecosystems , 2014, DOI: 10.1155/2014/714734
Abstract: Quantifying ecosystem carbon stocks is vital for understanding the relationship between changes in land use and cover (LULC) and carbon emissions; however, few studies have documented the impacts of carbon cycling on Miombo ecosystems. Here, we estimate the amounts of wood carbon which is stored and lost as a result of LULC changes in Kagoma Forest Reserve (KFR) for the periods between 1988 and 2010 using GIS data, Landsat imagery, and field observations. The land cover was captured on the basis of Landsat 5?TM and Landsat 7?ETM. The amounts of wood carbon stored and lost were estimated based on four previously developed allometric models. Spatial analysis of the Landsat images shows that in the year 1988, woodlands dominated the area by covering 32.66% whereas in the year 2010 the woodlands covered only 7.34% of the total area. The findings of the current study reveal that KFR had undergone notable changes in terms of LULC for the period of 1988–2010. It was estimated that the woodlands in the KFR lost an average of 4409.79?t . In this study, the amount of carbon stocks stored was estimated to be 21457.02 tonnes in tree stem biomass based on the area (1226.12?ha) that was covered by woodlands. We estimated that an average of 17.79?t was stored in the Miombo woodlands based on the four models. The efforts to ensure sustainable management of the Miombo ecosystem can contribute to the creation of a considerable carbon sink. 1. Introduction Miombo woodlands are widespread in the tropics, covering over 2.7 × 103?km2 in east, central, and southern Africa [1]. It occurs on poor soils derived from acid crystalline bedrock occurring under a hot, seasonally wet climate [2]. Its woody vegetation is mainly dominated by Brachystegia spp., Julbernardia spp., and Isoberlinia spp. [1]. Miombo woodlands ecosystems are considered to directly support the livelihood of an estimated 39 million people, particularly in low income rural communities in central African countries [1, 2]. The woodlands supply charcoal, firewood, fruits, building poles, and timber to over 15 million people living in the urban areas in the region [1]. Woody biomass consumption from Miombo woodland is said to amount to about 48?Tg?yr?1, releasing almost 22?Tg of Carbon to the atmosphere [2]. For example in Tanzania, forests and woodlands cover more than 40% of the total land surface and directly support the livelihood of over 85% of the rural poor [3]. Cultivation and deforestation mainly for charcoal production have been reported to be the major factors that contribute to the decline of Miombo
Estimating the Above-Ground Biomass in Miombo Savanna Woodlands (Mozambique, East Africa) Using L-Band Synthetic Aperture Radar Data  [PDF]
Jo?o M. B. Carreiras,Joana B. Melo,Maria J. Vasconcelos
Remote Sensing , 2013, DOI: 10.3390/rs5041524
Abstract: The quantification of forest above-ground biomass (AGB) is important for such broader applications as decision making, forest management, carbon (C) stock change assessment and scientific applications, such as C cycle modeling. However, there is a great uncertainty related to the estimation of forest AGB, especially in the tropics. The main goal of this study was to test a combination of field data and Advanced Land Observing Satellite (ALOS) Phased Array L-band Synthetic Aperture Radar (PALSAR) backscatter intensity data to reduce the uncertainty in the estimation of forest AGB in the Miombo savanna woodlands of Mozambique (East Africa). A machine learning algorithm, based on bagging stochastic gradient boosting (BagSGB), was used to model forest AGB as a function of ALOS PALSAR Fine Beam Dual (FBD) backscatter intensity metrics. The application of this method resulted in a coefficient of correlation (R) between observed and predicted (10-fold cross-validation) forest AGB values of 0.95 and a root mean square error of 5.03 Mg·ha ?1. However, as a consequence of using bootstrap samples in combination with a cross validation procedure, some bias may have been introduced, and the reported cross validation statistics could be overoptimistic. Therefore and as a consequence of the BagSGB model, a measure of prediction variability (coefficient of variation) on a pixel-by-pixel basis was also produced, with values ranging from 10 to 119% (mean = 25%) across the study area. It provides additional and complementary information regarding the spatial distribution of the error resulting from the application of the fitted model to new observations.
Biomass carbon stocks and their changes in northern China’s grasslands during 1982–2006
WenHong Ma,JingYun Fang,YuanHe Yang,Anwar Mohammat
Science China Life Sciences , 2010, DOI: 10.1007/s11427-010-4020-6
Abstract: 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.
Aboveground Woody Biomass, Carbon Stocks Potential in Selected Tropical Forest Patches of Tripura, Northeast India  [PDF]
Koushik Majumdar, Bal Krishan Choudhary, Badal Kumar Datta
Open Journal of Ecology (OJE) , 2016, DOI: 10.4236/oje.2016.610057
Abstract: To estimate woody plant biomass stocks in different patches of forest ecosystems, total 20, 500 × 10 m (0.5 ha) sized line transects were laid in a protected area of Tripura, Northeast India. Overall, 9160 individuals were measured at ≥10 cm diameter at breast height (dbh) in 10 ha sampled area. Estimation of biomass suggested that highest coefficient for allometric relationships between density and biomass in 10 dbh classes was observed in bamboo brakes (R2 = 0.90) than lowest for semi evergreen patch (R2 = 0.48). The stock of carbon (C) was differ significantly along the forest patches (F = 7.01, df = 3.19; p < 0.01). Most of biomass stock (69.38%) was accumulated in lower dbh class (<30 cm) and only 23% of biomass was estimated at higher dbh classes (> 70 cm). Range of biomass stock (37.85 - 85.58 Mg ha-1) was low, compared to other tropical forest ecosystems in India, which implies that the proper management is required to monitor regional ecosystem C pool.
Carbon Stocks in Aboveground and Belowground Biomass of Sub-Humid Tropical Forest in Southwestern Nigeria
Habeeb Ajibola Yusuf, Jesumbo Joseph Oludipe, Oluwatoyin Olajumoke Adeoye, Idowu Ezekiel Olorunfemi
Open Access Library Journal (OALib Journal) , 2019, DOI: 10.4236/oalib.1105588
This study aimed at estimation of carbon stocks in aboveground and below-ground biomass of sub-humid young forest land in south-western Nigeria. Different species of trees were analysed. Results gathered indicated that the forest studied had an average aboveground carbon stock of live trees as 0.00407 t. Terminalia superba (0.00698 t C) has the highest carbon stocks and diameter at breast height (Dbh) of 5.80 cm while Triplochiton scleroxy-lon contained the least stock of carbon (0.00212 t C) and Dbh of 3.55 cm. From the analysis, it was observed that total belowground biomass (BGB) was 32% of AGB. Positive linear relationship was observed between Dbh and the amount of carbon in the study area. It was also observed that a negative linear relationship exists between the aboveground biomass carbon (AGBC) and wood densities. This study indicates that the species of trees in the forest studied are effective carbon sink and can inhibit the effect of CO2 in the atmosphere. Three new models were developed using different input parameters and they all showed proximity to the 2005 allometric equation by Chave and his team.
Tree Allometry in Tropical Forest of Congo for Carbon Stocks Estimation in Above-Ground Biomass  [PDF]
Romeo Ekoungoulou, Xiaodong Liu, Jean Jo?l Loumeto, Suspense Averti Ifo, Yannick Enock Bocko, Fleury Edgard Koula, Shukui Niu
Open Journal of Forestry (OJF) , 2014, DOI: 10.4236/ojf.2014.45052
Abstract: The research was aimed to estimate the carbon stocks of above-ground biomass (AGB) in Lesiolouna forest in Republic of Congo. The methodology of Allometric equations was used to measure the carbon stock of Lesio-louna tropical rainforest. The research was done with six circular plots each 40 m of diameter, with a distance of 100 m between each plot, depending on the topography of the site of the installation of these plots. The six studied plots are divided in two sites, which are: Iboubikro and Ngambali. Thus, in the six plots, there are three plots in Iboubikro site and three plots in Ngambali site. The results of this study show that the average carbon stock of aboveground biomass (AGB) in six plots was 170.673 t C ha-1. So, the average of carbon stock of aboveground biomass (ABG) in Iboubikro site was 204.693 t C ha-1 and in the Ngambali site was 136.652 t C ha-1. In this forest ecosystem, the high stock of carbon was obtained in Plot 3, which was in Iboubikro site. Plot 3 contains 20 trees and an average DBH of 24.56 cm. However, the lowest carbon stock was obtained in Plot 4, which was in Ngambali site. Also, Plot 4 contains 11 trees and an average DBH of 31.86 cm. The results of this research indicate that, the forests in the study area are an important carbon reservoir, and they can also play a key role in mitigation of climate change.
Forest Biomass, Carbon Stocks, and Macrofungal Dynamics: A Case Study in Costa Rica  [PDF]
Carlos Rojas,Erick Calvo
International Journal of Forestry Research , 2014, DOI: 10.1155/2014/607372
Abstract: 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. 1. Introduction Macroscopic fungi within the group of the Basidiomycota stand out among human groups for their aesthetic beauty and role in sociocultural paradigms [1]. Ironically, the fungi are one of the biological groups for which limited scientific data in relation to ecosystem dynamics are available (e.g., [2]), and thus popular beliefs are dramatically based on speculation. In fact, the fungi comprise one of the groups for which fine information on natural history, ecological strategies, and across-level trophic relationships still accumulates at a slow pace (see [3]). An obvious constraint of the situation is that the study of modern evolutionary questions of forest functioning, particularly in tropical areas with high levels of nutrient recycling, develops at an even slower speed. The paradox of the research on the tree-fungus system in the tropics derives from the fact that even though it is an important component of forest dynamics, there are a comparatively small number of local scientists generating data about the different shapes of the relationship. In the past, some interactions such as saprophytism, parasitism, endophytism, lichenization, and mycorrhization have been used to generate functional data on tropical fungi (e.g., [4]). However, an integration with forest ecology research is weak, and thus the information generated has been useful for tropical fungal biologists but not necessarily for forest ecologists. For instance, in the case of mycorrhizal research, most of the efforts on tropical areas have focused on the applied aspects of the fungus-plant relationship (e.g., agriculture; see [5]).
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