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Aboveground woody biomass carbon dataset for the Latin American tropics and the Caribbean (~500m spatial resolution) generated by Woods Hole Research Center scientists and their collaborators. The Conservation Biology Institute created a continuous dataset by mosaicing national level biomass data provided by WHRC and converting it to carbon using a coefficient of 0.5 (Chave et al. 2005). The dataset was then converted from Float to Interger data type to minimize file size.The pixel values are in megagrams (Mg) of Aboveground Live Woody Carbon per Hectare (Mg/Ha).WHRC researchers produced national level maps showing the amount and spatial distribution of aboveground live woody vegetation biomass (for the period...
Observations from the moderate resolution imaging spectroradiometer (MODIS) were used in combination with a large data set of Field measurements to map woody above-ground biomass (AGB) across tropical Africa. We generated a best-quality cloud-free mosaic of MODIS satellite reflectance observations for the period 2000-2003 and used a regression tree model to predict AGB at 1 km resolution. Results based on a cross-validation approach show that the model explained 82% of the variance in AGB, with a root mean square error of 50.5 Mg ha-1 for a range of biomass between 0 and 454 Mg ha-1 . Analysis of lidar metrics from the Geoscience Laser Altimetry System (GLAS), which are sensitive to vegetation structure, indicate...
Observations from the moderate resolution imaging spectroradiometer (MODIS) were used in combination with a large data set of Field measurements to map woody above-ground biomass (AGB) across tropical Africa. We generated a best-quality cloud-free mosaic of MODIS satellite reflectance observations for the period 2000-2003 and used a regression tree model to predict AGB at 1 km resolution. Results based on a cross-validation approach show that the model explained 82% of the variance in AGB, with a root mean square error of 50.5 Mg ha-1 for a range of biomass between 0 and 454 Mg ha-1 . Analysis of lidar metrics from the Geoscience Laser Altimetry System (GLAS), which are sensitive to vegetation structure, indicate...
Abstract (from: http://link.springer.com/article/10.1007/s00442-014-2881-2): Forest biomass growth is almost universally assumed to peak early in stand development, near canopy closure, after which it will plateau or decline. The chronosequence and plot remeasurement approaches used to establish the decline pattern suffer from limitations and coarse temporal detail. We combined annual tree ring measurements and mortality models to address two questions: first, how do assumptions about tree growth and mortality influence reconstructions of biomass growth? Second, under what circumstances does biomass production follow the model that peaks early, then declines? We integrated three stochastic mortality models with...
Categories: Publication;
Types: Citation;
Tags: Birds,
Forests,
Landscapes,
Northeast CASC,
Wildlife and Plants,
The accompanying dataset was produced as part of a project funded under NASA’s Terrestrial Ecology Program and titled “The National Biomass and Carbon Dataset 2000 (NBCD 2000): A High Spatial Resolution Baseline to Reduce Uncertainty in Carbon Accounting and Flux Modeling.” The main objective of the project was to generate a high-resolution (30 m), year-2000 baseline estimate of basal area-weighted canopy height, aboveground live dry biomass, and standing carbon stock for the conterminou The accompanying dataset was produced as part of a project funded under NASA’s Terrestrial Ecology Program and titled “The National Biomass and Carbon Dataset 2000 (NBCD 2000): A High Spatial Resolution Baseline to Reduce...
Categories: Data;
Types: ArcGIS REST Map Service,
Map Service;
Tags: Biomass,
Carbon,
NBCD,
Woods Hole Field Center,
flux
Observations from the moderate resolution imaging spectroradiometer (MODIS) were used in combination with a large data set of Field measurements to map woody above-ground biomass (AGB) across tropical Africa. We generated a best-quality cloud-free mosaic of MODIS satellite reflectance observations for the period 2000-2003 and used a regression tree model to predict AGB at 1 km resolution. Results based on a cross-validation approach show that the model explained 82% of the variance in AGB, with a root mean square error of 50.5 Mg ha-1 for a range of biomass between 0 and 454 Mg ha-1 . Analysis of lidar metrics from the Geoscience Laser Altimetry System (GLAS), which are sensitive to vegetation structure, indicate...
Average vegetation carbon is calculated for 30 year periods for the historical period and for the future. Percent change is calculated as ((future – historical/historical) x 100). MC1 is a dynamic vegetation model for estimating the distribution of vegetation and associated ecosystem fluxes of carbon, nutrients, and water. It was created to assess the potential impacts of global climate change on ecosystem structure and function at a wide range of spatial scales from landscape to global. The model incorporates transient dynamics to make predictions about the patterns of ecological change. MC1 was created by combining physiologically based biogeographic rules defined in the MAPSS model with a modified version of...
Annual growth potential is an environmental data layer that is a proxy for annual plant biomass, which reflects potential forage for tortoises. This data layer was derived by calculating the difference in greenness (a measure of plant growth) between two highly contrasting years of annual plant production (Wallace and Thomas, 2008). The difference between MODIS-EVI images for 2002 (a very dry year) and 2005 (a very wet year) had high correlation with field measurements of annual plant cover collected on 36 plots in the Mojave National Preserve in 2005 (R2 = 0.63, p=0.01). The resulting values represent the potential for site specific food availability for desert tortoise.
Observations from the moderate resolution imaging spectroradiometer (MODIS) were used in combination with a large data set of Field measurements to map woody above-ground biomass (AGB) across tropical Africa. We generated a best-quality cloud-free mosaic of MODIS satellite reflectance observations for the period 2000-2003 and used a regression tree model to predict AGB at 1 km resolution. Results based on a cross-validation approach show that the model explained 82% of the variance in AGB, with a root mean square error of 50.5 Mg ha-1 for a range of biomass between 0 and 454 Mg ha-1 . Analysis of lidar metrics from the Geoscience Laser Altimetry System (GLAS), which are sensitive to vegetation structure, indicate...
Observations from the moderate resolution imaging spectroradiometer (MODIS) were used in combination with a large data set of Field measurements to map woody above-ground biomass (AGB) across tropical Africa. We generated a best-quality cloud-free mosaic of MODIS satellite reflectance observations for the period 2000-2003 and used a regression tree model to predict AGB at 1 km resolution. Results based on a cross-validation approach show that the model explained 82% of the variance in AGB, with a root mean square error of 50.5 Mg ha-1 for a range of biomass between 0 and 454 Mg ha-1 . Analysis of lidar metrics from the Geoscience Laser Altimetry System (GLAS), which are sensitive to vegetation structure, indicate...
Terrestrial net primary production (NPP) quantifies the amount of atmospheric carbon fixed by plants and accumulated as biomass. Previous studies have shown that climate constraints were relaxing with increasing temperature and solar radiation, allowing an upward trend in NPP from 1982 through 1999. The past decade (2000 to 2009) has been the warmest since instrumental measurements began, which could imply continued increases in NPP; however, our estimates suggest a reduction in the global NPP of 0.55 petagrams of carbon. Large-scale droughts have reduced regional NPP, and a drying trend in the Southern Hemisphere has decreased NPP in that area, counteracting the increased NPP over the Northern Hemisphere. A continued...
Pelagic fish communities (waters with depths >20 m) of Lakes Powell and Mead were examined quarterly from 1995 to1998 using vertical gill nets and a scientific echosounder. Nets captured a total of 449 fish consisting of striped bass (57%/45% [Lake Powell/Lake Mead]), threadfin shad (24%/50%), common carp (15%/4%), walleye (3%), channel catfish (2%), and rainbow trout (<1%). Each reservoir contained concentrations of pelagic species separated by expanses of habitat with few fish (<10 kg ? ha?1). Reservoirs experienced dramatic seasonal and annual fluctuations in pelagic biomass. Lake Powell?s biomass peaked at the Colorado River at 709.7 (�46.5) kg ? ha?1 and Lake Mead?s reached 291.9 (�58.2) kg ? ha?1 at Las Vegas...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Western North American Naturalist,
biomass,
densities,
distribution,
pelagic fisheries,
Downy brome (Bromus tectorum L.) is an alien grass that dominates disturbed ground in shrub-steppe ecosystems of the western United States. Responses of downy brome to added nitrogen and water were evaluated using intact soil cores obtained from an old field. Gas exchange data were gathered at the leaf and canopy scales. Stomatal conductance and net photosynthesis rates were greater at the leaf scale than at the canopy scale, decreased with time from germination, and were weakly affected by treatments. Water-use efficiency was weakly related to time from germination and treatments. Biomass was greater in the nitrogen-plus-water (7.4 g) treatment, compared with water (3.6 g), nitrogen (4.5 g), and control (3.3 g)...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Allen Press and Society for Range Management,
Bromus tectorum L.,
Journal of Range Management,
biomass,
conductance,
Encroachment of woody plants into grasslands, and subsequent brush management, are among the most prominent changes to occur in arid and semiarid systems over the past century. Despite the resulting widespread changes in landcover, substantial uncertainty about the biogeochemical impacts of woody proliferation and brush management exists. We explored the role of shrub encroachment and brush management on leaf litter decomposition in a semidesert grassland where velvet mesquite (Prosopis velutina) abundance has increased over the past 100 years. This change in physiognomy may affect decomposition directly, through altered litter quality or quantity, and indirectly through altered canopy structure. To assess the direct...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Arizona,
Biomass,
Desert Climate,
Ecological Applications,
Ecosystem,
This project was conducted to evaluate the feasibility of using geothermal effluents for developing and maintaining waterfowl wetlands. Information in the document pertains to a seven State area the West where geothermal resources have development potential. Information is included on physiochemical characteristics of geothermal effluents; known effects of constituents in the water on a wetland ecosystem and water quality criteria for maintaining a viable wetland; potential of sites for wetland development and disposal of effluent water from geothermal facilities; methods of ‘disposal of effluents, including advantages of each method and associated costs; legal and Institutional constraints which could affect geothermal...
The U.S. continues efforts to develop genetically superior short-rotation woody crops (hybrid poplar and willow) and herbaceous crops (switchgrass). These biomass crops can provide multiple environmental benefits as well as energy and fiber. This paper focuses on results of site-specific studies that are quantifying the environmental potential and ramifications of converting agricultural croplands to biomass crop production. At research-scales, no differences have been found in erosion and movement of nutrients from annual row crops, switchgrass, and tree crops with and without a cover crop in the initial year of establishment. Research- and watershed-scale studies on different soil types, in different regions,...
Biomass is the first-ever fuel used by humankind and is also the fuel which was the mainstay of the global fuel economy till the middle of the 18th century. Then fossil fuels took over because fossil fuels were not only more abundant and denser in their energy content, but also generated less pollution when burnt, in comparison to biomass. In recent years there is a resurgence of interest in biomass energy because biomass is perceived as a carbon-neutral source of energy unlike net carbon-emitting fossil fuels of which copious use has led to global warming and ocean acidification. The paper takes stock of the various sources of biomass and the possible ways in which it can be utilized for generating energy. It then...
A complete understanding of the resource consumption, embodied energy, and environmental emissions of civil projects in China is difficult due to the lack of comprehensive national statistics. To quantitatively assess the energy and environmental impacts of civil construction at a macro-level, this study developed a 24 sector environmental input-output life-cycle assessment model (I-O LCA) based on 2002 Chinese national economic and environmental data. The model generates an economy-wide inventory of energy use and environmental emissions. Estimates based on the level of economic activity related to planned future civil works in 2015 are made. Results indicate that the embodied energy of construction projects accounts...
There is a growing recognition that the interrelations between agriculture, food, bioenergy, and climate change have to be better understood in order to derive more realistic estimates of future bioenergy potentials. This article estimates global bioenergy potentials in the year 2050, following a “food first” approach. It presents integrated food, livestock, agriculture, and bioenergy scenarios for the year 2050 based on a consistent representation of FAO projections of future agricultural development in a global biomass balance model. The model discerns 11 regions, 10 crop aggregates, 2 livestock aggregates, and 10 food aggregates. It incorporates detailed accounts of land use, global net primary production (NPP)...
Categories: Publication;
Types: Citation;
Tags: Bioenergy potential,
Biomass,
Climate change,
Food,
Human appropriation of net primary production (HANPP),
Miscanthus is a newly introduced crop grown primarily to produce biomass for energy production and the area grown in the UK is anticipated to increase. Major differences in crop management from conventional arable crops have led to speculation that miscanthus may also have effects on farmland biodiversity. Six miscanthus fields were paired with six of a conventional crop, winter wheat, and bird diversity and abundance were compared in winter and during the breeding season along with potential food sources. Miscanthus fields had a greater abundance and diversity of birds than did wheat in winter and summer. In winter, the greater numbers of birds in miscanthus fields were probably attracted by the shelter provided...
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