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Sample records for biomass allocation patterns

  1. Biomass allocation patterns across China's terrestrial biomes.

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    Limei Wang

    Full Text Available Root to shoot ratio (RS is commonly used to describe the biomass allocation between below- and aboveground parts of plants. Determining the key factors influencing RS and interpreting the relationship between RS and environmental factors is important for biological and ecological research. In this study, we compiled 2088 pairs of root and shoot biomass data across China's terrestrial biomes to examine variations in the RS and its responses to biotic and abiotic factors including vegetation type, soil texture, climatic variables, and stand age. The median value of RS (RSm for grasslands, shrublands, and forests was 6.0, 0.73, and 0.23, respectively. The range of RS was considerably wide for each vegetation type. RS values for all three major vegetation types were found to be significantly correlated to mean annual precipitation (MAP and potential water deficit index (PWDI. Mean annual temperature (MAT also significantly affect the RS for forests and grasslands. Soil texture and forest origin altered the response of RS to climatic factors as well. An allometric formula could be used to well quantify the relationship between aboveground and belowground biomass, although each vegetation type had its own inherent allometric relationship.

  2. Pattern and control of biomass allocation across global forest ecosystems.

    Science.gov (United States)

    Jiang, Yongtao; Wang, Limei

    2017-07-01

    The underground part of a tree is an important carbon sink in forest ecosystems. Understanding biomass allocation between the below- and aboveground parts ( root:shoot ratios ) is necessary for estimation of the underground biomass and carbon pool. Nevertheless, large-scale biomass allocation patterns and their control mechanisms are not well identified. In this study, a large database of global forests at the community level was compiled to investigate the root:shoot ratios and their responses to environmental factors. The results indicated that both the aboveground biomass ( AGB ) and belowground biomass ( BGB ) of the forests in China (medians 73.0 Mg/ha and 17.0 Mg/ha, respectively) were lower than those worldwide (medians 120.3 Mg/ha and 27.7 Mg/ha, respectively). The root:shoot ratios of the forests in China (median = 0.23), however, were not significantly different from other forests worldwide (median = 0.24). In general, the allocation of biomass between the belowground and aboveground parts was determined mainly by the inherent allometry of the plant but also by environmental factors. In this study, most correlations between root:shoot ratios and environmental factors (development parameter, climate, altitude, and soil) were weak but significant ( p  BGB based on AGB across the entire database.

  3. Biomass Allocation Patterns across China’s Terrestrial Biomes

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    Wang, Limei; Li, Longhui; Chen, Xi; Tian, Xin; Wang, Xiaoke; Luo, Geping

    2014-01-01

    Root to shoot ratio (RS) is commonly used to describe the biomass allocation between below- and aboveground parts of plants. Determining the key factors influencing RS and interpreting the relationship between RS and environmental factors is important for biological and ecological research. In this study, we compiled 2088 pairs of root and shoot biomass data across China’s terrestrial biomes to examine variations in the RS and its responses to biotic and abiotic factors including vegetation type, soil texture, climatic variables, and stand age. The median value of RS (RSm) for grasslands, shrublands, and forests was 6.0, 0.73, and 0.23, respectively. The range of RS was considerably wide for each vegetation type. RS values for all three major vegetation types were found to be significantly correlated to mean annual precipitation (MAP) and potential water deficit index (PWDI). Mean annual temperature (MAT) also significantly affect the RS for forests and grasslands. Soil texture and forest origin altered the response of RS to climatic factors as well. An allometric formula could be used to well quantify the relationship between aboveground and belowground biomass, although each vegetation type had its own inherent allometric relationship. PMID:24710503

  4. Inherent and environmental patterns in biomass allocation and allometry among higher plants

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    Poorter, Hendrik

    2017-04-01

    It is well-known that plants may adjust the distribution of biomass over leaves, stems and roots depending on environmental conditions. It is also clear that size is an important factor as well. However, good quantitative insights are lacking. In this talk I analyse biomass allocation patterns to leaves, stems and roots of herbs and woody species. A database was compiled with 11.000 records of leaf, stem and root biomass for 1200 species. First, I'll derive general dose-response curves that describe the relationship between biomass allocation and the 12 most important a-biotic environmental factors and compare them with the changes in leaf, stem and root morphology. Second, I'll focus on allometric relationships between the various organs and test to what extent they comply with models like that for Metabolic Scaling Theory, where the slope of the log-log relationship between leaf and root biomass is expected to have a value of ¾. Third, I analyse how leaf, stem and root mass fractions change as a function of total plant size. This offers a great opportunity to test to what extent there are systematic differences in allocation patterns related to phylogeny (e.g. Gymnosperms vs. Angiosperms, grasses vs. herbaceous dicots) and functional group (e.g. deciduous vs. evergreens). Poorter et al. (2012) Biomass allocation to leaves, stems and roots: meta-analyses of interspecific variation and environmental control. New Phytol. 193: 30-50. Poorter & Sack (2012) Pitfalls and possibilities in the analysis of biomass allocation patterns in plants. Front. Plant Sci. 3: 259. Poorter et al. (2015) How does biomass distribution change with size and differ among species? New Phytol. 208: 736-749

  5. Pitfalls and possibilities in the analysis of biomass allocation patterns in plants

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    Hendrik ePoorter

    2012-12-01

    Full Text Available Plants can differentially allocate biomass to leaves, stems, roots and reproduction, and follow ontogenetic trajectories that interact with the prevailing climate. Various methodological tools exist to analyse the resulting allocation patterns, based either on the calculation of biomass ratios or fractions of different organs at a given point in time, or on a so-called allometric analysis of biomass data sampled across species or over an experimental growth period. We discuss the weak and strong points of each of these methods. Although both approaches have useful features, we suggest that often a plot of biomass fractions against total plant size, either across species or in the comparison of treatment effects, combines the best of both worlds.

  6. Biomass allocation and long-term growth patterns of temperate lianas in comparison with trees.

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    Ichihashi, Ryuji; Tateno, Masaki

    2015-08-01

    The host-dependent support habit of lianas is generally interpreted as a strategy designed to reduce resource investment in mechanical tissues; this allows preferential allocation to leaf and stem extension, thereby enhancing productivity and competitive abilities. However, this hypothesis has not been rigorously tested. We examined the aboveground allometries regarding biomass allocation (leaf mass and current-year stem mass (approximated as biomass allocated to extension growth) vs total aboveground mass) and long-term apparent growth patterns (height and aboveground mass vs age, i.e. numbers of growth rings) for nine deciduous liana species in Japan. Lianas had, on average, three- and five-fold greater leaf and current-year stem mass, respectively, than trees for a given aboveground mass, whereas the time course to reach the forest canopy was comparable and biomass accumulation during that period was only one-tenth that of co-occurring canopy trees. The balance between the lengths of yearly stem extension and existing older stems indicated that lianas lost c. 75% of stem length during growth to the canopy, which is probably a consequence of the host-dependent growth. Our observations suggest that, although lianas rely on hosts mechanically, allowing for short-term vigorous growth, this habit requires a large cost and could limit plant growth over protracted periods. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  7. Patterns of biomass allocation between foliage and woody structure: the effects of tree size and specific functional traits

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    Sylvanus Mensah

    2016-06-01

    Full Text Available Biomass allocation is closely related to species traits, resources availability and competitive abilities, and therefore it is often used to capture resource utilisation within plants. In this study, we searched for patterns in biomass allocation between foliage and wood (stem plus branch, and how they changed with tree size (diameter, species identity and functional traits (leaf area and specific wood density. Using data on the aboveground biomass of 89 trees from six species in a Mistbelt forest (South Africa, we evaluated the leaf to wood mass ratio (LWR. The effects of tree size, species identity and specific traits on LWR were tested using Generalised Linear Models. Tree size (diameter was the main driver of biomass allocation, with 44.43 % of variance explained. As expected, LWR declined significantly with increasing tree diameter. Leaf area (30.17% explained variance and wood density (12.61% explained variance also showed significant effects, after size effect was accounted for. Results also showed clear differences among species and between groups of species. Per unit of wood mass, more biomass is allocated to the foliage in the species with the larger leaf area. Inversely, less biomass is allocated to the foliage in species with higher wood density. Moreover, with increasing diameter, lower wood density species tended to allocate more biomass to foliage and less biomass to stems and branches. Overall, our results emphasise the influence of plant size and functional traits on biomass allocation, but showed that neither tree diameter and species identity nor leaf area and wood density are the only important variables.

  8. Herbivory alters plant carbon assimilation, patterns of biomass allocation and nitrogen use efficiency

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    Peschiutta, María Laura; Scholz, Fabián Gustavo; Goldstein, Guillermo; Bucci, Sandra Janet

    2018-01-01

    Herbivory can trigger physiological processes resulting in leaf and whole plant functional changes. The effects of chronic infestation by an insect on leaf traits related to carbon and nitrogen economy in three Prunus avium cultivars were assessed. Leaves from non-infested trees (control) and damaged leaves from infested trees were selected. The insect larvae produce skeletonization of the leaves leaving relatively intact the vein network of the eaten leaves and the abaxial epidermal tissue. At the leaf level, nitrogen content per mass (Nmass) and per area (Narea), net photosynthesis per mass (Amass) and per area (Aarea), photosynthetic nitrogen-use efficiency (PNUE), leaf mass per area (LMA) and total leaf phenols content were measured in the three cultivars. All cultivars responded to herbivory in a similar fashion. The Nmass, Amass, and PNUE decreased, while LMA and total content of phenols increased in partially damaged leaves. Increases in herbivore pressure resulted in lower leaf size and total leaf area per plant across cultivars. Despite this, stem cumulative growth tended to increase in infected plants suggesting a change in the patterns of biomass allocation and in resources sequestration elicited by herbivory. A larger N investment in defenses instead of photosynthetic structures may explain the lower PNUE and Amass observed in damaged leaves. Some physiological changes due to herbivory partially compensate for the cost of leaf removal buffering the carbon economy at the whole plant level.

  9. Floating capital pattern and biomass slope allocation method in the life history of calotropis procera (AIT.) AIT. F.

    OpenAIRE

    Ismail, A. M. A. [احمد محمد علي اسماعيل

    1992-01-01

    Plants of the woody perennial Calotropis procera (Asclepediaceae) were grown from seed to seed-set in an open field. Smith's slope allocation and fractional-allocation or percentage methods were used to study dry matter partitioning in the species. The two methods differed in thier predictions of the biomass allocated to the various organs. There were differences in the direction of change in the root/shoot ratio: increase, decrease and no change. The mean root/shoot ratio was 0.21:1 during t...

  10. Sensitivity of growth and biomass allocation patterns to increasing nitrogen: a comparison between ephemerals and annuals in the Gurbantunggut Desert, north-western China.

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    Zhou, Xiaobing; Zhang, Yuanming; Niklas, Karl J

    2014-02-01

    Biomass accumulation and allocation patterns are critical to quantifying ecosystem dynamics. However, these patterns differ among species, and they can change in response to nutrient availability even among genetically related individuals. In order to understand this complexity further, this study examined three ephemeral species (with very short vegetative growth periods) and three annual species (with significantly longer vegetative growth periods) in the Gurbantunggut Desert, north-western China, to determine their responses to different nitrogen (N) supplements under natural conditions. Nitrogen was added to the soil at rates of 0, 0.5, 1.0, 3.0, 6.0 and 24.0 g N m(-2) year(-1). Plants were sampled at various intervals to measure relative growth rate and shoot and root dry mass. Compared with annuals, ephemerals grew more rapidly, increased shoot and root biomass with increasing N application rates and significantly decreased root/shoot ratios. Nevertheless, changes in the biomass allocation of some species (i.e. Erodium oxyrrhynchum) in response to the N treatment were largely a consequence of changes in overall plant size, which was inconsistent with an optimal partitioning model. An isometric log shoot vs. log root scaling relationship for the final biomass harvest was observed for each species and all annuals, while pooled data of three ephemerals showed an allometric scaling relationship. These results indicate that ephemerals and annuals differ observably in their biomass allocation patterns in response to soil N supplements, although an isometric log shoot vs. log root scaling relationship was maintained across all species. These findings highlight that different life history strategies behave differently in response to N application even when interspecific scaling relationships remain nearly isometric.

  11. Biomass Resource Allocation among Competing End Uses

    Energy Technology Data Exchange (ETDEWEB)

    Newes, E.; Bush, B.; Inman, D.; Lin, Y.; Mai, T.; Martinez, A.; Mulcahy, D.; Short, W.; Simpkins, T.; Uriarte, C.; Peck, C.

    2012-05-01

    The Biomass Scenario Model (BSM) is a system dynamics model developed by the U.S. Department of Energy as a tool to better understand the interaction of complex policies and their potential effects on the biofuels industry in the United States. However, it does not currently have the capability to account for allocation of biomass resources among the various end uses, which limits its utilization in analysis of policies that target biomass uses outside the biofuels industry. This report provides a more holistic understanding of the dynamics surrounding the allocation of biomass among uses that include traditional use, wood pellet exports, bio-based products and bioproducts, biopower, and biofuels by (1) highlighting the methods used in existing models' treatments of competition for biomass resources; (2) identifying coverage and gaps in industry data regarding the competing end uses; and (3) exploring options for developing models of biomass allocation that could be integrated with the BSM to actively exchange and incorporate relevant information.

  12. Do plants modulate biomass allocation in response to petroleum pollution?

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    Nie, Ming; Yang, Qiang; Jiang, Li-Fen; Fang, Chang-Ming; Chen, Jia-Kuan; Li, Bo

    2010-01-01

    Biomass allocation is an important plant trait that responds plastically to environmental heterogeneities. However, the effects on this trait of pollutants owing to human activities remain largely unknown. In this study, we investigated the response of biomass allocation of Phragmites australis to petroleum pollution by a 13CO2 pulse-labelling technique. Our data show that plant biomass significantly decreased under petroleum pollution, but the root–shoot ratio for both plant biomass and 13C increased with increasing petroleum concentration, suggesting that plants could increase biomass allocation to roots in petroleum-polluted soil. Furthermore, assimilated 13C was found to be significantly higher in soil, microbial biomass and soil respiration after soils were polluted by petroleum. These results suggested that the carbon released from roots is rapidly turned over by soil microbes under petroleum pollution. This study found that plants can modulate biomass allocation in response to petroleum pollution. PMID:20484231

  13. Family Differences in Aboveground Biomass Allocation in Loblolly Pine

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    Scott D. Roberts

    2002-01-01

    The proportion of tree growth allocated to stemwood is an important economic component of growth efficiency. Differences in growth efficiency between species, or between families within species, may therefore be related to how growth is proportionally allocated between the stem and other aboveground biomass components. This study examines genetically related...

  14. Shoot and root biomass allocation and competitive hierarchies of ...

    African Journals Online (AJOL)

    Shoot and root biomass allocation and competitive hierarchies of four South African grass species on light, soil resources and cutting gradients. ... Aristida junciformis, produced nearly double the biomass of taller species such as Hyparrhenia hirta and Eragrostis curvula in the low-nutrient treatments, with the reverse being ...

  15. Above- and Belowground Biomass Allocation in Shrub Biomes across the Northeast Tibetan Plateau

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    Yang, Yuanhe; Yang, Lucun; Zhou, Guoying

    2016-01-01

    Biomass partitioning has been explored across various biomes. However, the strategies of allocation in plants still remain contentious. This study investigated allocation patterns of above- and belowground biomass at the community level, using biomass survey from the Tibetan Plateau. We explored above- and belowground biomass by conducting three consecutive sampling campaigns across shrub biomes on the northeast Tibetan Plateau during 2011–2013. We then documented the above-ground biomass (AGB), below-ground biomass (BGB) and root: shoot ratio (R/S) and the relationships between R/S and environment factors using data from 201 plots surveyed from 67 sites. We further examined relationships between above-ground and below-ground biomass across various shrub types. Our results indicated that the median values of AGB, BGB, and R/S in Tibetan shrub were 1102.55, 874.91 g m-2, and 0.85, respectively. R/S showed significant trend with mean annual precipitation (MAP), while decreased with mean annual temperature (MAT). Reduced major axis analysis indicated that the slope of the log-log relationship between above- and belowground biomass revealed a significant difference from 1.0 over space, supporting the optimal hypothesis. Interestingly, the slopes of the allometric relationship between log AGB and log BGB differed significantly between alpine and desert shrub. Our findings supported the optimal theory of above- and belowground biomass partitioning in Tibetan shrub, while the isometric hypothesis for alpine shrub at the community level. PMID:27119379

  16. Above- and Belowground Biomass Allocation in Shrub Biomes across the Northeast Tibetan Plateau.

    Science.gov (United States)

    Nie, Xiuqing; Yang, Yuanhe; Yang, Lucun; Zhou, Guoying

    2016-01-01

    Biomass partitioning has been explored across various biomes. However, the strategies of allocation in plants still remain contentious. This study investigated allocation patterns of above- and belowground biomass at the community level, using biomass survey from the Tibetan Plateau. We explored above- and belowground biomass by conducting three consecutive sampling campaigns across shrub biomes on the northeast Tibetan Plateau during 2011-2013. We then documented the above-ground biomass (AGB), below-ground biomass (BGB) and root: shoot ratio (R/S) and the relationships between R/S and environment factors using data from 201 plots surveyed from 67 sites. We further examined relationships between above-ground and below-ground biomass across various shrub types. Our results indicated that the median values of AGB, BGB, and R/S in Tibetan shrub were 1102.55, 874.91 g m-2, and 0.85, respectively. R/S showed significant trend with mean annual precipitation (MAP), while decreased with mean annual temperature (MAT). Reduced major axis analysis indicated that the slope of the log-log relationship between above- and belowground biomass revealed a significant difference from 1.0 over space, supporting the optimal hypothesis. Interestingly, the slopes of the allometric relationship between log AGB and log BGB differed significantly between alpine and desert shrub. Our findings supported the optimal theory of above- and belowground biomass partitioning in Tibetan shrub, while the isometric hypothesis for alpine shrub at the community level.

  17. Above- and Belowground Biomass Allocation in Shrub Biomes across the Northeast Tibetan Plateau.

    Directory of Open Access Journals (Sweden)

    Xiuqing Nie

    Full Text Available Biomass partitioning has been explored across various biomes. However, the strategies of allocation in plants still remain contentious. This study investigated allocation patterns of above- and belowground biomass at the community level, using biomass survey from the Tibetan Plateau. We explored above- and belowground biomass by conducting three consecutive sampling campaigns across shrub biomes on the northeast Tibetan Plateau during 2011-2013. We then documented the above-ground biomass (AGB, below-ground biomass (BGB and root: shoot ratio (R/S and the relationships between R/S and environment factors using data from 201 plots surveyed from 67 sites. We further examined relationships between above-ground and below-ground biomass across various shrub types. Our results indicated that the median values of AGB, BGB, and R/S in Tibetan shrub were 1102.55, 874.91 g m-2, and 0.85, respectively. R/S showed significant trend with mean annual precipitation (MAP, while decreased with mean annual temperature (MAT. Reduced major axis analysis indicated that the slope of the log-log relationship between above- and belowground biomass revealed a significant difference from 1.0 over space, supporting the optimal hypothesis. Interestingly, the slopes of the allometric relationship between log AGB and log BGB differed significantly between alpine and desert shrub. Our findings supported the optimal theory of above- and belowground biomass partitioning in Tibetan shrub, while the isometric hypothesis for alpine shrub at the community level.

  18. Identifying Memory Allocation Patterns in HEP Software

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    Kama, S.; Rauschmayr, N.

    2017-10-01

    HEP applications perform an excessive amount of allocations/deallocations within short time intervals which results in memory churn, poor locality and performance degradation. These issues are already known for a decade, but due to the complexity of software frameworks and billions of allocations for a single job, up until recently no efficient mechanism has been available to correlate these issues with source code lines. However, with the advent of the Big Data era, many tools and platforms are now available to do large scale memory profiling. This paper presents, a prototype program developed to track and identify each single (de-)allocation. The CERN IT Hadoop cluster is used to compute memory key metrics, like locality, variation, lifetime and density of allocations. The prototype further provides a web based visualization back-end that allows the user to explore the results generated on the Hadoop cluster. Plotting these metrics for every single allocation over time gives a new insight into application’s memory handling. For instance, it shows which algorithms cause which kind of memory allocation patterns, which function flow causes how many short-lived objects, what are the most commonly allocated sizes etc. The paper will give an insight into the prototype and will show profiling examples for the LHC reconstruction, digitization and simulation jobs.

  19. Resource Allocation Patterns and Student Achievement

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    James, Lori; Pate, James; Leech, Donald; Martin, Ellice; Brockmeier, Lantry; Dees, Elizabeth

    2011-01-01

    This quantitative research study was designed to examine the relationship between system resource allocation patterns and student achievement, as measured by eighth grade Criterion-Referenced Competency Test (CRCT) mathematics, eighth grade CRCT reading, eleventh grade Georgia High School Graduation Test (GHSGT) mathematics, eleventh grade and…

  20. Biomass and nutrient allocation strategies in a desert ecosystem in the Hexi Corridor, northwest China.

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    Zhang, Ke; Su, YongZhong; Yang, Rong

    2017-07-01

    The allocation of biomass and nutrients in plants is a crucial factor in understanding the process of plant structures and dynamics to different environmental conditions. In this study, we present a comprehensive scaling analysis of data from a desert ecosystem to determine biomass and nutrient (carbon (C), nitrogen (N), and phosphorus (P)) allocation strategies of desert plants from 40 sites in the Hexi Corridor. We found that the biomass and levels of C, N, and P storage were higher in shoots than in roots. Roots biomass and nutrient storage were concentrated at a soil depth of 0-30 cm. Scaling relationships of biomass, C storage, and P storage between shoots and roots were isometric, but that of N storage was allometric. Results of a redundancy analysis (RDA) showed that soil nutrient densities were the primary factors influencing biomass and nutrient allocation, accounting for 94.5% of the explained proportion. However, mean annual precipitation was the primary factor influencing the roots biomass/shoots biomass (R/S) ratio. Furthermore, Pearson's correlations and regression analyses demonstrated that although the biomass and nutrients that associated with functional traits primarily depended on soil conditions, mean annual precipitation and mean annual temperature had greater effects on roots biomass and nutrient storage.

  1. Biomass and its allocation in relation to temperature, precipitation, and soil nutrients in Inner Mongolia grasslands, China.

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    Kang, Muyi; Dai, Cheng; Ji, Wenyao; Jiang, Yuan; Yuan, Zhiyou; Chen, Han Y H

    2013-01-01

    Understanding and predicting ecosystem functioning such as biomass accumulation requires an accurate assessment of large-scale patterns of biomass distribution and partitioning in relation to climatic and soil environments. We sampled above- and belowground biomass from 26 sites spanning 1500 km in Inner Mongolian grasslands, compared the difference in aboveground, belowground biomass and below-aboveground biomass ratio (AGB, BGB, and B/A, respectively) among meadow steppe, typical steppe, and desert steppe types. The relationships between AGB, BGB, B/A and climatic and soil environments were then examined. We found that AGB and BGB differed significantly among three types of grasslands while B/A did not differ. Structural equation model analyses indicated that mean annual precipitation was the strongest positive driver for AGB and BGB. AGB was also positively associated with soil organic carbon, whereas B/A was positively associated with total soil nitrogen. These results indicated that precipitation positively influence plant production in Inner Mongolian grasslands. Contrary to the prediction from the optimal partitioning hypothesis, biomass allocation to belowground increased with soil total nitrogen, suggesting that more productive sites may increase belowground allocation as an adaptive strategy to potentially high fire frequencies.

  2. Biomass and its allocation in relation to temperature, precipitation, and soil nutrients in Inner Mongolia grasslands, China.

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    Muyi Kang

    Full Text Available AIM: Understanding and predicting ecosystem functioning such as biomass accumulation requires an accurate assessment of large-scale patterns of biomass distribution and partitioning in relation to climatic and soil environments. METHODS: We sampled above- and belowground biomass from 26 sites spanning 1500 km in Inner Mongolian grasslands, compared the difference in aboveground, belowground biomass and below-aboveground biomass ratio (AGB, BGB, and B/A, respectively among meadow steppe, typical steppe, and desert steppe types. The relationships between AGB, BGB, B/A and climatic and soil environments were then examined. RESULTS: We found that AGB and BGB differed significantly among three types of grasslands while B/A did not differ. Structural equation model analyses indicated that mean annual precipitation was the strongest positive driver for AGB and BGB. AGB was also positively associated with soil organic carbon, whereas B/A was positively associated with total soil nitrogen. CONCLUSIONS: These results indicated that precipitation positively influence plant production in Inner Mongolian grasslands. Contrary to the prediction from the optimal partitioning hypothesis, biomass allocation to belowground increased with soil total nitrogen, suggesting that more productive sites may increase belowground allocation as an adaptive strategy to potentially high fire frequencies.

  3. Genotypic Effects of Fertilization on Seedling Sweetgum Biomass Allocation, N Uptake, and N Use Efficiency

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    Scott X. Chang

    2001-01-01

    Full Text Available Screening and selecting tree genotypes that are responsive to N additions and that have high nutrient use efficiencies can provide better genetic material for short-rotation plantation establishment. A pot experiment was conducted to test the hypotheses that (1 sweetgum (Liquidambar styraciflua L. families have different patterns in biomass production and allocation, N uptake, and N use efficiency (NUE, because of their differences in growth strategies, and (2 sweetgum families that are more responsive to N additions will also have greater nutrient use efficiencies. Seedlings from two half-sib families (F10022 and F10023 that were known to have contrasting responses to fertility and other stress treatments were used for an experiment with two levels of N (0 vs. 100 kg N/ha equivalent and two levels of P (0 vs. 50 kg P/ha equivalent in a split-plot design. Sweetgum seedlings responded to N and P treatments rapidly, with increases in both size and biomass production, and those responses were greater with F10023 than with F10022. Growth response to N application was particularly strong. N and P application increased the proportional allocation of biomass to leaves. Under increased N supply, P application increased foliar N concentration and content, as well as total N uptake by the seedlings. However, NUE was decreased by N addition and was higher in F10023 than in F10022 when P was not limiting. A better understanding of genotype by fertility interactions is important in selecting genotypes for specific site conditions and for optimizing nutrient use in forestry production.

  4. Biomass Allocation and Growth Data of Seeded Plants

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set of leaf, stem, and root biomass for various plant taxa was compiled from the primary literature of the 20th century with a significant portion derived...

  5. Biomass Allocation and Growth Data of Seeded Plants

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set of leaf, stem, and root biomass for various plant taxa was compiled from the primary literature of the 20th century with a significant...

  6. Research and evaluation of biomass resources/conversion/utilization systems. Biomass allocation model. Volume 1: Test and appendices A & B

    Science.gov (United States)

    Stringer, R. P.; Ahn, Y. K.; Chen, H. T.; Helm, R. W.; Nelson, E. T.; Shields, K. J.

    1981-08-01

    A biomass allocation model was developed to show the most profitable combination of biomass feedstocks, thermochemical conversion processes, and fuel products to serve the seasonal conditions in a regional market. This optimization model provides a tool for quickly calculating which of a large number of potential biomass missions is the most profitable mission. Other components of the system serve as a convenient storage and retrieval mechanism for biomass marketing and thermochemical conversion processing data. The system can be accessed through the use of a computer terminal, or it could be adapted to a microprocessor. A User's Manual for the system is included. Biomass derived fuels included in the data base are the following: medium Btu gas, low Btu gas, substitute natural gas, ammonia, methanol, electricity, gasoline, and fuel oil.

  7. The effect of water availability on plastic responses and biomass allocation in early growth traits of Pinus radiata D. Don

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    S. E. Espinoza

    2013-04-01

    Full Text Available Aim of study: The aim of the study was to assess the effect of water availability on plastic responses and biomass allocation in early growth traits of Pinus radiata D. Don.Area of study: Seedlings of 69 families of P. radiata belonging to five different sites in Central Chile, ranging from coastal range to fothills of the Andes, were grown in controlled conditions to evaluate differences in response to watering.Material and methods: The seedlings were subjected to two watering regimes: well-watered treatment, in which seedlings were watered daily, and water stress treatment in which seedlings were subjected to three cyclic water deficits by watering to container capacity on 12 days cycles each. After twenty-eight weeks root collar diameter, height, shoot dry weight (stem + needles, root dry weight, total dry weight, height/diameter ratio and root/shoot ratio were recorded. Patterns and amounts of phenotypic changes, including changes in biomass allocation, were analyzed.Main results: Families from coastal sites presented high divergence for phenotypic changes, allocating more biomass to shoots, and those families from interior sites presented low phenotypic plasticity, allocating more biomass to roots at the expense of shoots. These changes are interpreted as a plastic response and leads to the conclusion that the local landrace of P. radiata in Chile originating from contrasting environments possess distinct morphological responses to water deficit which in turn leads to phenotypic plasticity.Research highlights: Families belonging to sandy soil sites must be considered for tree breeding in dry areas, selecting those with high root: shoot ratio.Key words: early testing; environmental interaction; ontogeny; plasticity index; water stress.

  8. Carbon allocation patterns in boreal and hemiboreal forest ecosystems along the gradient of soil fertility

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    Kriiska, Kaie; Uri, Veiko; Frey, Jane; Napa, Ülle; Kabral, Naima; Soosaar, Kaido; Rannik, Kaire; Ostonen, Ivika

    2017-04-01

    Carbon (C) allocation plays a critical role in forest ecosystem carbon cycling. Changes in C allocation alter ecosystems carbon sequestration and plant-soil-atmosphere gas exchange, hence having an impact on the climate. Currently, there is lack of reliable indicators that show the direction of C accumulation patterns in forest ecosystems on regional scale. The first objective of our study was to determine the variability of carbon allocation in hemiboreal coniferous forests along the gradient of soil fertility in Estonia. We measured C stocks and fluxes, such as litter, fine root biomass and production, soil respiration etc. in 8 stands of different site types - Scots pine (Cladonia, Vaccinium, Myrtillus, Fragaria) and Norway spruce (Polytrichum, Myrtillus, Oxalis, Calamagrostis alvar). The suitability of above- and belowground litter production (AG/BG) ratio was analysed as a carbon allocation indicator. The second aim of the study was to analyse forest C allocation patterns along the north-south gradient from northern boreal Finland to hemiboreal Estonia. Finally, C sequestration in silver birch and grey alder stands were compared with coniferous stands in order to determine the impact of tree species on carbon allocation. Preliminary results indicate that estimated AG/BG ratio (0.5 ... 3.0) tends to decrease with increasing soil organic horizon C/N ratio, indicating that in less fertile sites more carbon is allocated into belowground through fine root growth and in consequence the soil organic carbon stock increases. Similar trends were found on the north-south forest gradient. However, there was a significant difference between coniferous and broadleaf stands in C allocation patterns. Net ecosystem exchange in Estonian coniferous stands varied from -1.64 ... 3.95 t C ha-1 yr-1, whereas older stands tended to be net carbon sources.

  9. Changes in biomass allocation in species rich meadow after abandonment: Ecological strategy or allometry?

    Czech Academy of Sciences Publication Activity Database

    Bartušková, Alena; Doležal, Jiří; Janeček, Štěpán; Lanta, V.; Klimešová, Jitka

    2015-01-01

    Roč. 17, č. 5 (2015), s. 379-387 ISSN 1433-8319 R&D Projects: GA ČR GB14-36079G Institutional support: RVO:67985939 Keywords : Biomass allocation * species-rich meadow * abandonment Subject RIV: EF - Botanics Impact factor: 3.578, year: 2015

  10. Regional allocation of biomass to U.S. energy demands under a portfolio of policy scenarios.

    Science.gov (United States)

    Mullins, Kimberley A; Venkatesh, Aranya; Nagengast, Amy L; Kocoloski, Matt

    2014-01-01

    The potential for widespread use of domestically available energy resources, in conjunction with climate change concerns, suggest that biomass may be an essential component of U.S. energy systems in the near future. Cellulosic biomass in particular is anticipated to be used in increasing quantities because of policy efforts, such as federal renewable fuel standards and state renewable portfolio standards. Unfortunately, these independently designed biomass policies do not account for the fact that cellulosic biomass can equally be used for different, competing energy demands. An integrated assessment of multiple feedstocks, energy demands, and system costs is critical for making optimal decisions about a unified biomass energy strategy. This study develops a spatially explicit, best-use framework to optimally allocate cellulosic biomass feedstocks to energy demands in transportation, electricity, and residential heating sectors, while minimizing total system costs and tracking greenhouse gas emissions. Comparing biomass usage across three climate policy scenarios suggests that biomass used for space heating is a low cost emissions reduction option, while biomass for liquid fuel or for electricity becomes attractive only as emissions reduction targets or carbon prices increase. Regardless of the policy approach, study results make a strong case for national and regional coordination in policy design and compliance pathways.

  11. Seasonal evolution of carbon allocation to biomass in a French beech forest.

    Science.gov (United States)

    Heid, Laura; Calvaruso, Christophe; Conil, Sébastien; Turpault, Marie-Pierre; Longdoz, Bernard

    2015-04-01

    The objective of this study is to get a better understanding of ecosystem behavior in term of assimilated carbon (C) use. In the global climate change context, this C allocation could play a critical role in predicting ecosystems long terms emissions (Trumbore 2006) and has become a major goal of several emergent studies The monthly C allocation has been determined for a 50-year old beech forest located in north-east of France through the quantification of Gross Primary Production (GPP), biomass production and some of its components (holocelluloses, lignin). In a second phase, the potential factors influencing those productions and allocations throughout a year have been assessed. The temporal evolution of GPP was obtained from the partitioning of eddy-covariance flux measurements and monitored for one year. It was connected to tree aboveground C biomass growth at a monthly step. To achieve the latter, site specific allometric equations were used with trees diameter at breast height (DBH) measured monthly during the growing season on one hand and, on the other hand, C concentrations were deduced from analyses on trunk cores (sampled monthly) and on leaves and bulk branches cores (sampled at the beginning and at the end of the growing season). The C allocated to the aboveground biomass was then estimated, along with the portion allocated to structural C. The results show the delay existing between the end of the tree growth and carbon assimilation. We analyze the possibility to explain this divergence by a compensation coming from the C concentration evolution. Keywords: Carbon allocation, Forest, Biomass production, Carbon concentration, Eddy Covariance Trumbore S. 2006. Carbon Respired by Terrestrial Ecosystems - Recent Progress and Challenges. Global Change Biology 12 (2): 141-53.

  12. Remotely-sensed indicators of N-related biomass allocation in Schoenoplectus acutus

    Science.gov (United States)

    O’Connell, Jessica L.; Byrd, Kristin B.; Kelly, Maggi

    2014-01-01

    Coastal marshes depend on belowground biomass of roots and rhizomes to contribute to peat and soil organic carbon, accrete soil and alleviate flooding as sea level rises. For nutrient-limited plants, eutrophication has either reduced or stimulated belowground biomass depending on plant biomass allocation response to fertilization. Within a freshwater wetland impoundment receiving minimal sediments, we used experimental plots to explore growth models for a common freshwater macrophyte, Schoenoplectus acutus. We used N-addition and control plots (4 each) to test whether remotely sensed vegetation indices could predict leaf N concentration, root:shoot ratios and belowground biomass of S. acutus. Following 5 months of summer growth, we harvested whole plants, measured leaf N and total plant biomass of all above and belowground vegetation. Prior to harvest, we simulated measurement of plant spectral reflectance over 164 hyperspectral Hyperion satellite bands (350–2500 nm) with a portable spectroradiometer. N-addition did not alter whole plant, but reduced belowground biomass 36% and increased aboveground biomass 71%. We correlated leaf N concentration with known N-related spectral regions using all possible normalized difference (ND), simple band ratio (SR) and first order derivative ND (FDN) and SR (FDS) vegetation indices. FDN1235, 549 was most strongly correlated with leaf N concentration and also was related to belowground biomass, the first demonstration of spectral indices and belowground biomass relationships. While S. acutus exhibited balanced growth (reduced root:shoot ratio with respect to nutrient addition), our methods also might relate N-enrichment to biomass point estimates for plants with isometric root growth. For isometric growth, foliar N indices will scale equivalently with above and belowground biomass. Leaf N vegetation indices should aid in scaling-up field estimates of biomass and assist regional monitoring.

  13. [Biomass- and energy allocation in Eucalyptus urophylla x Eucalyptus tereticornis plantations at different stand ages].

    Science.gov (United States)

    Zhou, Qun-Ying; Chen, Shao-Xiong; Han, Fei-Yang; Chen, Wen-Ping; Wu, Zhi-Hua

    2010-01-01

    An investigation was made on the biomass- and energy allocation in 1-4-year-old Eucalyptus urophylla x Eucalyptus tereticornis plantations at Beipo Forest Farm of Suixi County in Guangdong Province. Stand age had significant effects on the retained biomass of the plantations (P branch > bark > root > leaf, and that in 3- and 4 -year-old plantations was in order of stem > root > branch > bark > leaf. The mean ash content (AC) of the five components at different stand ages ranged from 0.47% to 5.91%, being the highest in bark and the lowest in stem. The mean gross caloric value (GCV) and ash free caloric value (AFCV) of different components ranged from 17.33 to 20. 60 kJ x g(-1) and from 18.42 to 21.59 kJ x g(-1) respectively. Of all the components, leaf had the highest GVC and AFCV, while bark had the lowest ones. Stand age had significant effects on the GVC of branch, stem, and bark, and on the AFCV of leaf, stem, and bark (P 0.05). The retained energy of 1-4-year-old plantations ranged from 199.98 to 2837.20 GJ x hm(-2), with significant differences among the stand ages (P < 0.01). The retained energy of various components and plantations increased with stand age, and the energy allocation of various components had the same trend as biomass allocation.

  14. Effects of soil C:N:P stoichiometry on biomass allocation in the alpine and arid steppe systems.

    Science.gov (United States)

    Wang, Xiaodan; Ma, Xingxing; Yan, Yan

    2017-03-01

    Soil nutrients strongly influence biomass allocation. However, few studies have examined patterns induced by soil C:N:P stoichiometry in alpine and arid ecosystems. Samples were collected from 44 sites with similar elevation along the 220-km transect at spatial intervals of 5 km along the northern Tibetan Plateau. Aboveground biomass (AGB) levels were measured by cutting a sward in each plot. Belowground biomass (BGB) levels were collected from soil pits in a block of 1 m × 1 m in actual root depth. We observed significant decreases in AGB and BGB levels but increases in the BGB:AGB ratio with increases in latitude. Although soil is characterized by structural complexity and spatial heterogeneity, we observed remarkably consistent C:N:P ratios within the cryic aridisols. We observed significant nonlinear relationships between the soil N:P and BGB:AGB ratios. The critical N:P ratio in soils was measured at approximately 2.0, above which the probability of BGB:AGB response to nutrient availability is small. These findings serve as interesting contributions to the global data pool on arid plant stoichiometry, given the previously limited knowledge regarding high-altitude regions.

  15. Mechanical stimuli regulate the allocation of biomass in trees: demonstration with young Prunus avium trees.

    Science.gov (United States)

    Coutand, Catherine; Dupraz, Christian; Jaouen, Gaëlle; Ploquin, Stéphane; Adam, Boris

    2008-06-01

    Plastic tree-shelters are increasingly used to protect tree seedlings against browsing animals and herbicide drifts. The biomass allocation in young seedlings of deciduous trees is highly disturbed by common plastic tree-shelters, resulting in poor root systems and reduced diameter growth of the trunk. The shelters have been improved by creating chimney-effect ventilation with holes drilled at the bottom, resulting in stimulated trunk diameter growth, but the root deficit has remained unchanged. An experiment was set up to elucidate the mechanisms behind the poor root growth of sheltered Prunus avium trees. Tree seedlings were grown either in natural windy conditions or in tree-shelters. Mechanical wind stimuli were suppressed in ten unsheltered trees by staking. Mechanical stimuli (bending) of the stem were applied in ten sheltered trees using an original mechanical device. Sheltered trees suffered from poor root growth, but sheltered bent trees largely recovered, showing that mechano-sensing is an important mechanism governing C allocation and the shoot-root balance. The use of a few artificial mechanical stimuli increased the biomass allocation towards the roots, as did natural wind sway. It was demonstrated that there was an acclimation of plants to the imposed strain. This study suggests that if mechanical stimuli are used to control plant growth, they should be applied at low frequency in order to be most effective. The impact on the functional equilibrium hypothesis that is used in many tree growth models is discussed. The consequence of the lack of mechanical stimuli should be incorporated in tree growth models when applied to environments protected from the wind (e.g. greenhouses, dense forests).

  16. Effect of temperature on biomass allocation in seedlings of two contrasting genotypes of the oilseed crop Ricinus communis.

    Science.gov (United States)

    Ribeiro, Paulo R; Zanotti, Rafael F; Deflers, Carole; Fernandez, Luzimar G; Castro, Renato D de; Ligterink, Wilco; Hilhorst, Henk W M

    2015-08-01

    Ricinus communis is becoming an important crop for oil production, and studying the physiological and biochemical aspects of seedling development may aid in the improvement of crop quality and yield. The objective of this study was to assess the effect of temperature on biomass allocation in two R. communis genotypes. Biomass allocation was assessed by measuring dry weight of roots, stems, and cotyledons of seedlings grown at three different temperatures. Root length of each seedling was measured. Biomass allocation was strongly affected by temperature. Seedlings grown at 25°C and 35°C showed greater biomass than seedlings grown at 20°C. Cotyledon and stem dry weight increased for both genotypes with increasing temperature, whereas root biomass allocation showed a genotype-dependent behavior. Genotype MPA11 showed a continuous increase in root dry weight with increasing temperature, while genotype IAC80 was not able to sustain further root growth at higher temperatures. Based on metabolite and gene expression profiles, genotype MPA11 increases its level of osmoprotectant molecules and transcripts of genes encoding for antioxidant enzymes and heat shock proteins to a higher extent than genotype IAC80. This might be causal for the ability to maintain homeostasis and support root growth at elevated temperatures in genotype MPA11. Copyright © 2015 Elsevier GmbH. All rights reserved.

  17. See the forest for the trees: Whole-plant allocation patterns and regulatory mechanisms in Norway spruce

    Science.gov (United States)

    Huang, Jianbei; Behrendt, Thomas; Hammerbacher, Almuth; Weinhold, Alexander; Hellén, Heidi; Reichelt, Michael; Wisthaler, Armin; Dam, Nicole; Trumbore, Susan; Hartmann, Henrik

    2017-04-01

    For more than 40 years plant carbon (C) allocation have been of central interest to plant scientists. Most studies on C allocation focus on either biomass partitioning (e.g., root:shoot ratios), particular fluxes (e.g., non-structural carbohydrate, NSC; biogenic emissions of volatile organic compounds, VOCs) or short-term proportional allocation patterns (e.g., pulse-chase studies using isotopic tracers). However, a thorough understanding of C allocation priorities, especially at the whole-plant level, requires assessing all of these aspects together. We investigated C allocation trade-off in Norway spruce (Picea abies) saplings by assessing whole-plant fluxes (assimilation, respiration and VOCs) and biomass partitioning (structural biomass; NSC; secondary metabolites, SMs). The study was carried out over 8 weeks and allowed us, by modifying atmospheric CO2 concentrations ([CO2]), manipulating plant carbon (C) availability. Treatments included control (400 ppm), carbon compensation (down to 120 ppm) and starvation (down to 50 ppm) C availability levels. Reductions in [CO2] aimed to reveal plant allocation strategies assuming that pools receiving more C than others under C limitation have a high allocation priority. Respiration was less sensitive to declining [CO2] compared to assimilation, NSC and SMs. Strong declines in NSC at low [CO2] suggest that respiration was maintained by using stored NSC. Furthermore, reduced NSC and SMs concentrations also indicate preferential C allocation to growth over NSC and SMs at low C availability. SMs decreased to a lesser extent than NSC in old needles, and remained relatively constant in branches until death from starvation. These results suggest that pools of stored NSC may serve as a buffer for respiration or growth under C limitation but also that SMs remain largely inaccessible for metabolism once they are stored in tissues. VOCs emissions, however, showed contrasting responses to [CO2]; oxygenated VOCs (methanol and

  18. Effects of nutrient availabiiity on biomass allocation as well as constitutive and rapid induced herbivore resistance in poplar

    Science.gov (United States)

    Carolyn Glynn; Daniel A. Herms; Marie Egawa; Robert Hansen; William J. Mattson

    2003-01-01

    Many studies have examined effects of nutrient availability on constitutive herbivore resistance of plants, but few have addressed effects on expression of rapid induced resistance (RIR). We quantified effects of two levels of nutrient availability on growth, biomass allocation, photosynthesis, and constitutive secondary metabolism of black poplar (>i>Populus...

  19. Effect of temperature on biomass allocation in seedlings of two contrasting genotypes of the oilseed crop Ricinus communis

    NARCIS (Netherlands)

    Ribeiro de Jesus, P.R.; Zanotti, R.F.; Deflers, C.; Fernandez, L.G.; Castro, De R.D.; Ligterink, W.; Hilhorst, H.W.M.

    2015-01-01

    Ricinus communis is becoming an important crop for oil production, and studying the physiological and biochemical aspects of seedling development may aid in the improvement of crop quality and yield. The objective of this study was to assess the effect of temperature on biomass allocation in two R.

  20. Deciduous and evergreen trees differ in juvenile biomass allometries because of differences in allocation to root storage

    NARCIS (Netherlands)

    Tomlinson, K.W.; Langevelde, van F.; Ward, D.; Bongers, F.J.J.M.; Alves da Silva, D.; Prins, H.H.T.; Bie, de S.; Sterck, F.J.

    2013-01-01

    Background and Aims - Biomass partitioning for resource conservation might affect plant allometry, accounting for a substantial amount of unexplained variation in existing plant allometry models. One means of resource conservation is through direct allocation to storage in particular organs. In this

  1. Aboveground and belowground biomass allocation in native Prosopis caldenia Burkart secondaries woodlands in the semi-arid Argentinean pampas

    International Nuclear Information System (INIS)

    Risio, Lucia; Herrero, Celia; Bogino, Stella M.; Bravo, Felipe

    2014-01-01

    The woodlands in the south-west of the Argentinean pampas are dominated by Prosopis Caldenia Burkart (calden). The current deforestation rate of this woodlands is 0.82% per year. Different compensation initiatives have begun that recognize the role of forests as environmental service providers. The financial incentives they offer make it necessary to quantify the amount of carbon stored in the forest biomass. A model for estimating calden biomass was developed. Thirty-eight trees were selected, felled and divided into sections. An equation system was fitted using joint generalized regression to ensure the additivity property. A weighted regression was used to avoid heteroscedasticity. In these woodlands fire is the main disturbance and it can modify tree allometry, due this all models included the area of the base of the stem and tree height as independent variables since it indirectly collects this variability. Total biomass and the stem fraction had the highest R2 A dj. values (0.75), while branches with a diameter less than 7 cm had the lowest (0.58). Tree biomass was also analyzed by partitioning into the basic fractions of stem, crown, roots, and the root/shoot ratio. Biomass allocation was greatest in the crown fraction and the mean root/shoot ratio was 0.58. The carbon stock of the caldenales considering only calden tree biomass is 20.2 Mg ha −1 . While the overall carbon balance of the region is negative (deforestation and biomass burning, the remnant forested area has increased their calden density and in an indirect way his carbon sequestration capacity could also be increased. - Highlights: • A model for estimating aboveground and belowground Prosopis caldenia biomass was developed. • Biomass allocation into the tree and the root/shoot ratio were analyzed. • The equation systems presented had made it possible to more accurately estimate the biomass stored in calden woodlands

  2. Nitrogen nutrition of Canna indica: Effects of ammonium versus nitrate on growth, biomass allocation, photosynthesis, nitrate reductase activity and N uptake rates

    DEFF Research Database (Denmark)

    Konnerup, Dennis; Brix, Hans

    2010-01-01

    The effects of inorganic nitrogen (N) source (NH4+, NO3- or both) on growth, biomass allocation, photosynthesis, N uptake rate, nitrate reductase activity and mineral composition of Canna indica were studied in hydroponic culture. The relative growth rates (0.05-0.06 g g-1 d-1), biomass allocation...

  3. Importance of whole-plant biomass allocation and reproductive timing to habitat differentiation across the North American sunflowers.

    Science.gov (United States)

    Mason, Chase M; Goolsby, Eric W; Davis, Kaleigh E; Bullock, Devon V; Donovan, Lisa A

    2017-05-01

    Trait-based plant ecology attempts to use small numbers of functional traits to predict plant ecological strategies. However, a major gap exists between our understanding of organ-level ecophysiological traits and our understanding of whole-plant fitness and environmental adaptation. In this gap lie whole-plant organizational traits, including those that describe how plant biomass is allocated among organs and the timing of plant reproduction. This study explores the role of whole-plant organizational traits in adaptation to diverse environments in the context of life history, growth form and leaf economic strategy in a well-studied herbaceous system. A phylogenetic comparative approach was used in conjunction with common garden phenotyping to assess the evolution of biomass allocation and reproductive timing across 83 populations of 27 species of the diverse genus Helianthus (the sunflowers). Broad diversity exists among species in both relative biomass allocation and reproductive timing. Early reproduction is strongly associated with resource-acquisitive leaf economic strategy, while biomass allocation is less integrated with either reproductive timing or leaf economics. Both biomass allocation and reproductive timing are strongly related to source site environmental characteristics, including length of the growing season, temperature, precipitation and soil fertility. Herbaceous taxa can adapt to diverse environments in many ways, including modulation of phenology, plant architecture and organ-level ecophysiology. Although leaf economic strategy captures one key aspect of plant physiology, on their own leaf traits are not particularly predictive of ecological strategies in Helianthus outside of the context of growth form, life history and whole-plant organization. These results highlight the importance of including data on whole-plant organization alongside organ-level ecophysiological traits when attempting to bridge the gap between functional traits and plant

  4. Deciduous and evergreen trees differ in juvenile biomass allometries because of differences in allocation to root storage.

    Science.gov (United States)

    Tomlinson, Kyle W; van Langevelde, Frank; Ward, David; Bongers, Frans; da Silva, Dulce Alves; Prins, Herbert H T; de Bie, Steven; Sterck, Frank J

    2013-08-01

    Biomass partitioning for resource conservation might affect plant allometry, accounting for a substantial amount of unexplained variation in existing plant allometry models. One means of resource conservation is through direct allocation to storage in particular organs. In this study, storage allocation and biomass allometry of deciduous and evergreen tree species from seasonal environments were considered. It was expected that deciduous species would have greater allocation to storage in roots to support leaf regrowth in subsequent growing seasons, and consequently have lower scaling exponents for leaf to root and stem to root partitioning, than evergreen species. It was further expected that changes to root carbohydrate storage and biomass allometry under different soil nutrient supply conditions would be greater for deciduous species than for evergreen species. Root carbohydrate storage and organ biomass allometries were compared for juveniles of 20 savanna tree species of different leaf habit (nine evergreen, 11 deciduous) grown in two nutrient treatments for periods of 5 and 20 weeks (total dry mass of individual plants ranged from 0·003 to 258·724 g). Deciduous species had greater root non-structural carbohydrate than evergreen species, and lower scaling exponents for leaf to root and stem to root partitioning than evergreen species. Across species, leaf to stem scaling was positively related, and stem to root scaling was negatively related to root carbohydrate concentration. Under lower nutrient supply, trees displayed increased partitioning to non-structural carbohydrate, and to roots and leaves over stems with increasing plant size, but this change did not differ between leaf habits. Substantial unexplained variation in biomass allometry of woody species may be related to selection for resource conservation against environmental stresses, such as resource seasonality. Further differences in plant allometry could arise due to selection for different types

  5. Modeling efficient resource allocation patterns for arable crop ...

    African Journals Online (AJOL)

    optimum plans. This should be complemented with strong financial support, farm advisory services and adequate supply of modern inputs at fairly competitive prices would enhance the prospects of the small holder farmers. Keywords: efficient, resource allocation, optimization, linear programming, gross margin ...

  6. Effects of Grazing on Above- vs. Below-Ground Biomass Allocation of Alpine Grasslands on the Northern Tibetan Plateau.

    Directory of Open Access Journals (Sweden)

    Chaoxu Zeng

    Full Text Available Biomass allocation is an essential concept for understanding above- vs. below-ground functions and for predicting the dynamics of community structure and ecosystem service under ongoing climate change. There is rare available knowledge of grazing effects on biomass allocation in multiple zonal alpine grassland types along climatic gradients across the Northern Tibetan Plateau. We collected the peak above- and below-ground biomass (AGB and BGB values at 106 pairs of well-matched grazed vs. fenced sites during summers of 2010-2013, of which 33 pairs were subject to meadow, 52 to steppe and 21 to desert-steppe. The aboveground net primary productivity (ANPP was represented by the peak AGB while the belowground net primary productivity (BNPP was estimated from ANPP, the ratio of living vs. dead BGB, and the root turnover rate. Two-ways analyses of variance (ANOVA and paired samples comparisons with t-test were applied to examine the effects of pasture managements (PMS, i.e., grazed vs. fenced and zonal grassland types on both ANPP and BNPP. Allometric and isometric allocation hypotheses were also tested between logarithmically transformed ANPP and BNPP using standardized major axis (SMA analyses across grazed, fenced and overall sites. In our study, a high community-dependency was observed to support the allometric biomass allocation hypothesis, in association with decreased ANPP and a decreasing-to-increasing BNPP proportions with increasing aridity across the Northern Tibetan Plateau. Grazing vs. fencing seemed to have a trivial effect on ANPP compared to the overwhelming influence of different zonal grassland types. Vegetation links above- and below-ground ecological functions through integrated meta-population adaptive strategies to the increasing severity of habitat conditions. Therefore, more detailed studies on functional diversity are essentially to achieve conservation and sustainability goals under ongoing climatic warming and intensifying

  7. Effects of Grazing on Above- vs. Below-Ground Biomass Allocation of Alpine Grasslands on the Northern Tibetan Plateau.

    Science.gov (United States)

    Zeng, Chaoxu; Wu, Jianshuang; Zhang, Xianzhou

    2015-01-01

    Biomass allocation is an essential concept for understanding above- vs. below-ground functions and for predicting the dynamics of community structure and ecosystem service under ongoing climate change. There is rare available knowledge of grazing effects on biomass allocation in multiple zonal alpine grassland types along climatic gradients across the Northern Tibetan Plateau. We collected the peak above- and below-ground biomass (AGB and BGB) values at 106 pairs of well-matched grazed vs. fenced sites during summers of 2010-2013, of which 33 pairs were subject to meadow, 52 to steppe and 21 to desert-steppe. The aboveground net primary productivity (ANPP) was represented by the peak AGB while the belowground net primary productivity (BNPP) was estimated from ANPP, the ratio of living vs. dead BGB, and the root turnover rate. Two-ways analyses of variance (ANOVA) and paired samples comparisons with t-test were applied to examine the effects of pasture managements (PMS, i.e., grazed vs. fenced) and zonal grassland types on both ANPP and BNPP. Allometric and isometric allocation hypotheses were also tested between logarithmically transformed ANPP and BNPP using standardized major axis (SMA) analyses across grazed, fenced and overall sites. In our study, a high community-dependency was observed to support the allometric biomass allocation hypothesis, in association with decreased ANPP and a decreasing-to-increasing BNPP proportions with increasing aridity across the Northern Tibetan Plateau. Grazing vs. fencing seemed to have a trivial effect on ANPP compared to the overwhelming influence of different zonal grassland types. Vegetation links above- and below-ground ecological functions through integrated meta-population adaptive strategies to the increasing severity of habitat conditions. Therefore, more detailed studies on functional diversity are essentially to achieve conservation and sustainability goals under ongoing climatic warming and intensifying human

  8. [Effects of elevated CO2 concentration and nitrogen deposition on the biomass accumulation and allocation in south subtropical main native tree species and their mixed communities].

    Science.gov (United States)

    Zhao, Liang; Zhou, Guo-yi; Zhang, De-qiang; Duan, Hong-lang; Liu, Ju-xiu

    2011-08-01

    A 5-year experiment was conducted to study the effects of simulated elevated CO2 concentration, nitrogen deposition, and their combination on the biomass accumulation and allocation in five south subtropical native tree species Schima superba, Ormosia pinnata, Acmena acuminatissima, Syzygium hancei, and Castanopsis hystrix and their mixed communities. The test tree species had different responses in their biomass accumulation and allocation to the elevated CO2 concentration and nitrogen deposition. Elevated CO2 concentration and nitrogen deposition increased the biomass of legume species by 49.3% and 71.0%, respectively, and promoted the biomass accumulation in sun species. Nitrogen deposition increased the biomass of shade-preference species significantly, but elevated CO2 concentration was in adverse. Elevated CO2 concentration inhibited the biomass allocation in the belowground part of sun species but promoted the biomass allocation in the belowground part of shade-preference species. Elevated CO2 concentration, nitrogen deposition, and their interaction all promoted the biomass accumulation in mixed communities. Elevated CO2 concentration increased the biomass accumulation in the belowground part of the communities, while nitrogen deposition increased the biomass accumulation in the aboveground part. Under the background of global climate change, Ormosia pinnata and Castanopsis hystrix tended to be the appropriate species for carbon fixation in south subtropical area.

  9. [Characteristics of Stipa grandis growth and reproductive biomass allocation at different hill position of Xilingol grassland, Inner Mongolia].

    Science.gov (United States)

    Gao, Hui; Gao, Yu-bao; Liu, Hai-ying; Liu, Jing-ling

    2009-09-01

    An investigation was conducted on the vegetative and reproductive biomass allocation of Stipa grandis at the hill-top and hill-foot of Xilingol grassland, and relatedness- and factor analyses were made to study the effects of hill position on the S. grandis seed biomass. Significant differences were observed in the vegetative and reproductive growth of S. grandis plants at the hill-top and hill-foot. At hill-foot, the height and number of non-flowering S. grandis ramets increased by 24.69% and 35.37%, respectively, the number of flowering ramets increased by 102.97%, the vegetative, reproductive, and total biomass increased by 44.14%, 95.59% and 47.45%, respectively, and the 100-grain mass increased by 25.00%, as compared with those at hill-top. The seed biomass of S. grandis at hill-top was mainly affected by soil moisture content, while that at hill-foot was mainly affected by soil pH. Hill position induced the differentiation of soil moisture and N contents, and made the S. grandis at the fertile hill-foot allocating more energy to its sexual reproduction.

  10. Effects of a three-year exposure to ambient ozone on biomass allocation in poplar using ethylenediurea

    International Nuclear Information System (INIS)

    Hoshika, Yasutomo; Pecori, Francesco; Conese, Ilaria; Bardelli, Tommaso; Marchi, Enrico; Manning, William J.; Badea, Ovidiu; Paoletti, Elena

    2013-01-01

    We examined the effect of ambient ozone on visible foliar injury, growth and biomass in field-grown poplar cuttings of an Oxford clone sensitive to ozone (Populus maximoviczii Henry × berolinensis Dippel) irrigated with ethylenediurea (EDU) or water for three years. EDU is used as an ozone protectant for plants. Protective effects of EDU on ozone visible injury were found. As a result, poplar trees grown under EDU treatment increased leaves, lateral branches and root density in the third year, although no significant enhancement of stem height and diameter was found. Ambient ozone (AOT40, 24.6 ppm h; diurnal hourly average, 40.3 ppb) may finally reduce carbon gain by reducing the number of branches, and thus sites for leaf formation, in ozone-sensitive poplar trees under not-limiting conditions. -- Highlights: •A fast-growing ozone-sensitive poplar clone was treated with the ozone protectant ethylenediurea (EDU) for three years. •Ambient ozone reduced allocation of biomass to leaves, roots and lateral branches. •Effects on stem length and diameter were not significant. •EDU protected from ozone visible foliar injury and reduction of biomass accumulation. -- Ozone reduced allocation of biomass to leaves, roots and lateral branches, but did not affect stem length and diameter

  11. Seedling growth and biomass allocation in relation to leaf habit and shade tolerance among 10 temperate tree species.

    Science.gov (United States)

    Modrzyński, Jerzy; Chmura, Daniel J; Tjoelker, Mark G

    2015-08-01

    Initial growth of germinated seeds is an important life history stage, critical for establishment and succession in forests. Important questions remain regarding the differences among species in early growth potential arising from shade tolerance. In addition, the role of leaf habit in shaping relationships underlying shade tolerance-related differences in seedling growth remains unresolved. In this study we examined variation in morphological and physiological traits among seedlings of 10 forest tree species of the European temperate zone varying in shade tolerance and leaf habit (broadleaved winter-deciduous species vs needle-leaved conifers) during a 10-week period. Seeds were germinated and grown in a controlled environment simulating an intermediate forest understory light environment to resolve species differences in initial growth and biomass allocation. In the high-resource experimental conditions during the study, seedlings increased biomass allocation to roots at the cost of leaf biomass independent of shade tolerance and leaf habit. Strong correlations between relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR), specific leaf area (SLA) and leaf mass fraction (LMF) indicate that physiology and biomass allocation were equally important determinants of RGR as plant structure and leaf morphology among these species. Our findings highlight the importance of seed mass- and seed size-related root morphology (specific root length-SRL) for shade tolerance during early ontogeny. Leaf and plant morphology (SLA, LAR) were more successful in explaining variation among species due to leaf habit than shade tolerance. In both broadleaves and conifers, shade-tolerant species had lower SRL and greater allocation of biomass to stems (stem mass fraction). Light-seeded shade-intolerant species with greater SRL had greater RGR in both leaf habit groups. However, the greatest plant mass was accumulated in the group of heavy-seeded shade

  12. C3 and C4 biomass allocation responses to elevated CO2 and nitrogen: contrasting resource capture strategies

    Science.gov (United States)

    White, K.P.; Langley, J.A.; Cahoon, D.R.; Megonigal, J.P.

    2012-01-01

    Plants alter biomass allocation to optimize resource capture. Plant strategy for resource capture may have important implications in intertidal marshes, where soil nitrogen (N) levels and atmospheric carbon dioxide (CO2) are changing. We conducted a factorial manipulation of atmospheric CO2 (ambient and ambient + 340 ppm) and soil N (ambient and ambient + 25 g m-2 year-1) in an intertidal marsh composed of common North Atlantic C3 and C4 species. Estimation of C3 stem turnover was used to adjust aboveground C3 productivity, and fine root productivity was partitioned into C3-C4 functional groups by isotopic analysis. The results suggest that the plants follow resource capture theory. The C3 species increased aboveground productivity under the added N and elevated CO2 treatment (P 2 alone. C3 fine root production decreased with added N (P 2 (P = 0.0481). The C4 species increased growth under high N availability both above- and belowground, but that stimulation was diminished under elevated CO2. The results suggest that the marsh vegetation allocates biomass according to resource capture at the individual plant level rather than for optimal ecosystem viability in regards to biomass influence over the processes that maintain soil surface elevation in equilibrium with sea level.

  13. Vegetation in karst terrain of southwestern China allocates more biomass to roots

    Science.gov (United States)

    Ni, J.; Luo, D. H.; Xia, J.; Zhang, Z. H.; Hu, G.

    2015-07-01

    In mountainous areas of southwestern China, especially Guizhou province, continuous, broadly distributed karst landscapes with harsh and fragile habitats often lead to land degradation. Research indicates that vegetation located in karst terrains has low aboveground biomass and land degradation that reduces vegetation biomass, but belowground biomass measurements are rarely reported. Using the soil pit method, we investigated the root biomass of karst vegetation in five land cover types: grassland, grass-scrub tussock, thorn-scrub shrubland, scrub-tree forest, and mixed evergreen and deciduous forest in Maolan, southern Guizhou province, growing in two different soil-rich and rock-dominated habitats. The results show that roots in karst vegetation, especially the coarse roots, and roots in rocky habitats are mostly distributed in the topsoil layers (89 % on the surface up to 20 cm depth). The total root biomass in all habitats of all vegetation degradation periods is 18.77 Mg ha-1, in which roots in rocky habitat have higher biomass than in earthy habitat, and coarse root biomass is larger than medium and fine root biomass. The root biomass of mixed evergreen and deciduous forest in karst habitat (35.83 Mg ha-1) is not greater than that of most typical, non-karst evergreen broad-leaved forests in subtropical regions of China, but the ratio of root to aboveground biomass in karst forest (0.37) is significantly greater than the mean ratio (0.26 ± 0.07) of subtropical evergreen forests. Vegetation restoration in degraded karst terrain will significantly increase the belowground carbon stock, forming a potential regional carbon sink.

  14. Floral bud damage compensation by branching and biomass allocation in genotypes of Brassica napus with different architecture and branching potential.

    Directory of Open Access Journals (Sweden)

    Amélie ePinet

    2015-02-01

    Full Text Available Plant branching is a key process in the yield elaboration of winter oilseed rape (WOSR. It is also involved in plant tolerance to flower damage because it allows the setting of new fertile inflorescences. Here we characterize the changes in the branching and distribution of the number of pods between primary and secondary inflorescences in response to floral bud clippings. Then we investigate the impacts of the modifications in branching on the biomass allocation and its consequence on the crop productivity (harvest index. These issues were addressed on plants with contrasted architecture and branching potential, using three genotypes (Exocet, Pollen, and Gamin grown under two levels of nitrogen fertilization. Clipping treatments of increasing intensities were applied to either inflorescences or flower buds.We were able to show that restoration of the number of pods after clipping is the main lever for the compensation. Genotypes presented different behaviors in branching and biomass allocation as a function of clipping treatments. The number of fertile ramifications increased for the high intensities of clipping. In particular, the growth of secondary ramifications carried by branches developed before clipping has been observed. The proportions of yield and of number of pods carried by these secondary axes increased and became almost equivalent to the proportion carried by primary inflorescences. In terms of biomass allocation, variations have also been evidenced in the relationship between pod dry mass on a given axis and the number of pods set, while the shoot/root ratio was not modified. The harvest index presented different responses: it decreased after flower buds clipping, while it was maintained after the clipping of the whole inflorescences. The results are discussed relative to their implications regarding the identification of interesting traits to be target in breeding programs in order to improve WOSR tolerance.

  15. Elevated air humidity affects hydraulic traits and tree size but not biomass allocation in young silver birches (Betula pendula

    Directory of Open Access Journals (Sweden)

    Arne eSellin

    2015-10-01

    Full Text Available As changes in air temperature, precipitation, and air humidity are expected in the coming decades, studies on the impact of these environmental shifts on plant growth and functioning are of major importance. Greatly understudied aspects of climate change include consequences of increasing air humidity on forest ecosystems, predicted for high latitudes. The main objective of this study was to find a link between hydraulic acclimation and shifts in trees’ resource allocation in silver birch (Betula pendula Roth in response to elevated air relative humidity (RH. A second question was whether the changes in hydraulic architecture depend on tree size. Two years of application of increased RH decreased the biomass accumulation in birch saplings, but the biomass partitioning among aboveground parts (leaves, branches, and stems remained unaffected. Increased stem Huber values (xylem cross-sectional area to leaf area ratio observed in trees under elevated RH did not entail changes in the ratio of non-photosynthetic to photosynthetic tissues. The reduction of stem-wood density is attributable to diminished mechanical load imposed on the stem, since humidified trees had relatively shorter crowns. Growing under higher RH caused hydraulic conductance of the root system (KR to increase, while KR (expressed per unit leaf area decreased and leaf hydraulic conductance increased with tree size. Saplings of silver birch acclimate to increasing air humidity by adjusting plant morphology (live crown length, slenderness, specific leaf area, and fine-root traits and wood density rather than biomass distribution among aboveground organs. The treatment had a significant effect on several hydraulic properties of the trees, while the shifts were largely associated with changes in tree size but not in biomass allocation.

  16. Embryo cell allocation patterns are not altered by biopsy but can be linked with further development.

    Science.gov (United States)

    Sepulveda-Rincon, L P; Islam, N; Marsters, P; Campbell, B K; Beaujean, N; Maalouf, W E

    2017-12-01

    It has been suggested that first embryo cleavage can be related with the embryonic-abembryonic axis at blastocyst stage in mice. Thus, cells of the 2-cell embryo might be already biased to form the inner cell mass or trophectoderm. This study was conducted to observe the possible effects of embryo biopsy on cell allocation patterns during embryo preimplantation in two different mouse strains and the effects of these patterns on further development. First, one blastomere of the 2-cell embryo was injected with a lipophilic tracer and cell allocation patterns were observed at blastocyst stage. Blastocysts were classified into orthogonal, deviant or random pattern. For the first experiment, embryos were biopsied at 8-cell stage and total cell counts (TCC) were annotated. Furthermore, non-biopsied blastocysts were transferred into foster mothers. Then, pups and their organs were weighed two weeks after birth. Random pattern was significantly recurrent (≈60%), against orthogonal (patterns among groups. These patterns were not affected by biopsy procedure. However, TCC on deviant embryos were reduced after biopsy. Moreover, no differences were found between patterns for implantation rates, litter size, live offspring and organ weights (lungs, liver, pancreas and spleen). However, deviant pups presented heavier hearts and orthogonal pups presented lighter kidneys among the group. In conclusion, these results suggest that single blastomere removal does not disturb cell allocation patterns during pre-implantation. Nonetheless, the results suggest that embryos following different cell allocation patterns present different coping mechanisms against in vitro manipulations and further development might be altered. © 2017 Society for Reproduction and Fertility.

  17. Nutrition and bud removal affect biomass and nutrient allocation in Douglas-fir and western red cedar.

    Science.gov (United States)

    Hawkins, B. J.; Henry, G.

    1999-03-01

    Seedlings of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western red cedar (Thuja plicata J. Donn ex D. Don) were grown at high (250 mg l(-1)) and low (20 mg l(-1)) nitrogen (N) supply for a year. Before the second growing season, half of the seedlings in each nutrient treatment were allocated to the other treatment. Half of the seedlings in each nutrient treatment then had all growing points removed. Biomass and N, phosphorus (P) and potassium (K) concentrations of old and new shoots and roots were measured three times in the second year to test the interaction of current-year and previous-year nutrient supply on biomass and nutrient allocation in these two species with different growth habits. Pruned seedlings served as controls. Unpruned seedlings of both species increased in height throughout the second growing season, except for Douglas-fir in the N250 --> N20 treatment. Repeated pruning did not prevent new shoot growth, but resulted in a 12 to 52% reduction in biomass of new shoots and new and old roots. Seedlings receiving a low N supply in the first growing season were more severely affected by pruning than seedings receiving a high N supply. Growth was reduced more by pruning in western red cedar than in Douglas-fir. Concentrations of N, P and K were higher in pruned seedlings than in unpruned seedlings. Although dry weights of all plant parts in all treatments increased throughout the second growing season, some retranslocation of N, P and K was observed from old shoots of both species in the N250 --> N20 and N20 --> N20 treatments after August. Quantities of N, P and K retranslocated were greatest in seedlings grown the previous year in the high-N treatment.

  18. Allocation pattern in the financing of colleges of legal and Islamic ...

    African Journals Online (AJOL)

    Makerere Journal of Higher Education ... This study investigated the allocation pattern in the financing of colleges of Legal and Islamic Studies in Nigeria with special regard to the adequacy of the funding. The sample ... The findings showed that there is general under-funding of these colleges within the period considered.

  19. Changes in biomass allocation buffer low CO2effects on tree growth during the last glaciation.

    Science.gov (United States)

    Li, Guangqi; Gerhart, Laci M; Harrison, Sandy P; Ward, Joy K; Harris, John M; Prentice, I Colin

    2017-02-24

    Isotopic measurements on junipers growing in southern California during the last glacial, when the ambient atmospheric [CO 2 ] (c a ) was ~180 ppm, show the leaf-internal [CO 2 ] (c i ) was approaching the modern CO 2 compensation point for C 3 plants. Despite this, stem growth rates were similar to today. Using a coupled light-use efficiency and tree growth model, we show that it is possible to maintain a stable c i /c a ratio because both vapour pressure deficit and temperature were decreased under glacial conditions at La Brea, and these have compensating effects on the c i /c a ratio. Reduced photorespiration at lower temperatures would partly mitigate the effect of low c i on gross primary production, but maintenance of present-day radial growth also requires a ~27% reduction in the ratio of fine root mass to leaf area. Such a shift was possible due to reduced drought stress under glacial conditions at La Brea. The necessity for changes in allocation in response to changes in [CO 2 ] is consistent with increased below-ground allocation, and the apparent homoeostasis of radial growth, as c a increases today.

  20. Biomass allocation, relative competitive ability and water use efficiency of two dominant species in semiarid Loess Plateau under water stress.

    Science.gov (United States)

    Xu, Bing-Cheng; Xu, Wei-Zhou; Huang, Jin; Shan, Lun; Li, Feng-Min

    2011-12-01

    A better understanding of the growth and interspecific competition of native dominant species under water stress should aid in prediction of succession in plant communities. In addition, such research would guide the selection of appropriate conservation and agricultural utilization of plants in semiarid environments that have not been very well characterized. Biomass production and allocation, relative competitive ability and water use efficiency of one C(4) herbaceous grass (Bothriochloa ischaemum) and one C(3) leguminous subshrub (Lespedeza davurica), both important species from the semiarid Loess Plateau of China, were investigated in a pot-cultivation experiment. The experiment was conducted using a replacement series design in which B. ischaemum and L. davurica were grown with twelve plants per pot, in seven combinations of the two species (12:0, 10:2, 8:4, 6:6, 4:8, 2:10, and 0:12). Three levels of water treatments included sufficient water supply (HW), moderate water stress (MW) and severe water stress (LW). These treatments were applied after seedling establishment and remained until the end of the experiment. Biomass production and its partitioning, and transpiration water use efficiency (TWUE) were determined at the end of the experiment. Interspecific competitive indices (competitive ratio (CR), aggressiveness (A) and relative yield total (RYT)) were calculated from the dry weight for shoots, roots and total biomass. Water stress decreased biomass production of both species in monoculture and mixture. The growth of L. davurica was restrained in their mixtures for each water treatment. L. davurica had significantly (Pwater treatment and proportion within the replacement series. Aggressiveness (A) values for B. ischaemum with respect to L. davurica were negative only at the proportions of B. ischaemum to L. davurica being 8:4 and 10:2 in LW treatment. B. ischaemum had a significantly (Pwater treatment, and water stress considerably reduced its relative CR

  1. Luxury consumption of soil nutrients: a possible competitive strategy in above-ground and below-ground biomass allocation and root morphology for slow-growing arctic vegetation?

    NARCIS (Netherlands)

    Wijk, van M.T.; Williams, M.; Gough, L.; Hobbie, S.E.; Shaver, G.R.

    2003-01-01

    1 A field-experiment was used to determine how plant species might retain dominance in an arctic ecosystem receiving added nutrients. We both measured and modelled the above-ground and below-ground biomass allocation and root morphology of non-acidic tussock tundra near Toolik Lake, Alaska, after 4

  2. Effect of culture and density on aboveground biomass allocation of 12 years old loblolly pine trees in the upper coastal plain and piedmont of Georgia and Alabama

    Science.gov (United States)

    Santosh Subedi; Dr. Michael Kane; Dr. Dehai Zhao; Dr. Bruce Borders; Dr. Dale Greene

    2012-01-01

    We destructively sampled a total of 192 12-year-old loblolly pine trees from four installations established by the Plantation Management Research Cooperative (PMRC) to analyze the effects of planting density and cultural intensity on tree level biomass allocation in the Piedmont and Upper Coastal Plain of Georgia and Alabama. Each installation had 12 plots, each plot...

  3. Assessment of carbon allocation and biomass production in a natural stand of the salt marsh plant Spartina anglica using C- 13

    NARCIS (Netherlands)

    Hemminga, M.A.; Huiskes, A.H.L.; Steegstra, M.; Van Soelen, J.

    1996-01-01

    The proportional allocation of photosynthetically fixed carbon to the root and shoot system of salt marsh plants is an important element in the carbon cycle of tidal salt marshes. The commonly applied field methods giving insight on this point are based on successive harvesting of biomass. These

  4. Allocation pattern, ion partitioning, and chlorophyll a fluorescence in Arundo donax L. in responses to salinity stress

    Czech Academy of Sciences Publication Activity Database

    Pompeiano, Antonio; Landi, M.; Meloni, G.; Vita, F.; Guglielminetti, L.; Guidi, L.

    2017-01-01

    Roč. 151, č. 4 (2017), s. 613-622 ISSN 1126-3504 Institutional support: RVO:67179843 Keywords : biomass allocation * giant reed * photoinhibition * proline * salt stress Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 1.390, year: 2016

  5. Plasticity in seedling morphology, biomass allocation and physiology among ten temperate tree species in response to shade is related to shade tolerance and not leaf habit.

    Science.gov (United States)

    Chmura, D J; Modrzyński, J; Chmielarz, P; Tjoelker, M G

    2017-03-01

    Mechanisms of shade tolerance in tree seedlings, and thus growth in shade, may differ by leaf habit and vary with ontogeny following seed germination. To examine early responses of seedlings to shade in relation to morphological, physiological and biomass allocation traits, we compared seedlings of 10 temperate species, varying in their leaf habit (broadleaved versus needle-leaved) and observed tolerance to shade, when growing in two contrasting light treatments - open (about 20% of full sunlight) and shade (about 5% of full sunlight). We analyzed biomass allocation and its response to shade using allometric relationships. We also measured leaf gas exchange rates and leaf N in the two light treatments. Compared to the open treatment, shading significantly increased traits typically associated with high relative growth rate (RGR) - leaf area ratio (LAR), specific leaf area (SLA), and allocation of biomass into leaves, and reduced seedling mass and allocation to roots, and net assimilation rate (NAR). Interestingly, RGR was not affected by light treatment, likely because of morphological and physiological adjustments in shaded plants that offset reductions of in situ net assimilation of carbon in shade. Leaf area-based rates of light-saturated leaf gas exchange differed among species groups, but not between light treatments, as leaf N concentration increased in concert with increased SLA in shade. We found little evidence to support the hypothesis of a increased plasticity of broadleaved species compared to needle-leaved conifers in response to shade. However, an expectation of higher plasticity in shade-intolerant species than in shade-tolerant ones, and in leaf and plant morphology than in biomass allocation was supported across species of contrasting leaf habit. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  6. Decompositions of injection patterns for nodal flow allocation in renewable electricity networks

    Science.gov (United States)

    Schäfer, Mirko; Tranberg, Bo; Hempel, Sabrina; Schramm, Stefan; Greiner, Martin

    2017-08-01

    The large-scale integration of fluctuating renewable power generation represents a challenge to the technical and economical design of a sustainable future electricity system. In this context, the increasing significance of long-range power transmission calls for innovative methods to understand the emerging complex flow patterns and to integrate price signals about the respective infrastructure needs into the energy market design. We introduce a decomposition method of injection patterns. Contrary to standard flow tracing approaches, it provides nodal allocations of link flows and costs in electricity networks by decomposing the network injection pattern into market-inspired elementary import/export building blocks. We apply the new approach to a simplified data-driven model of a European electricity grid with a high share of renewable wind and solar power generation.

  7. Net primary productivity, allocation pattern and carbon use efficiency in an apple orchard assessed by integrating eddy covariance, biometric and continuous soil chamber measurements

    Directory of Open Access Journals (Sweden)

    D. Zanotelli

    2013-05-01

    Full Text Available Carbon use efficiency (CUE, the ratio of net primary production (NPP over gross primary production (GPP, is a functional parameter that could possibly link the current increasingly accurate global GPP estimates with those of net ecosystem exchange, for which global predictors are still unavailable. Nevertheless, CUE estimates are actually available for only a few ecosystem types, while information regarding agro-ecosystems is scarce, in spite of the simplified spatial structure of these ecosystems that facilitates studies on allocation patterns and temporal growth dynamics. We combined three largely deployed methods, eddy covariance, soil respiration and biometric measurements, to assess monthly values of CUE, NPP and allocation patterns in different plant organs in an apple orchard during a complete year (2010. We applied a measurement protocol optimized for quantifying monthly values of carbon fluxes in this ecosystem type, which allows for a cross check between estimates obtained from different methods. We also attributed NPP components to standing biomass increments, detritus cycle feeding and lateral exports. We found that in the apple orchard, both net ecosystem production and gross primary production on a yearly basis, 380 ± 30 g C m−2 and 1263 ± 189 g C m−2 respectively, were of a magnitude comparable to those of natural forests growing in similar climate conditions. The largest differences with respect to forests are in the allocation pattern and in the fate of produced biomass. The carbon sequestered from the atmosphere was largely allocated to production of fruit: 49% of annual NPP was taken away from the ecosystem through apple production. Organic material (leaves, fine root litter, pruned wood and early fruit falls contributing to the detritus cycle was 46% of the NPP. Only 5% was attributable to standing biomass increment, while this NPP component is generally the largest in forests. The CUE, with an annual average of 0.71

  8. Light energy partitioning, photosynthetic efficiency and biomass allocation in invasive Prunus serotina and native Quercus petraea in relation to light environment, competition and allelopathy.

    Science.gov (United States)

    Robakowski, Piotr; Bielinis, Ernest; Sendall, Kerrie

    2018-02-07

    This study addressed whether competition under different light environments was reflected by changes in leaf absorbed light energy partitioning, photosynthetic efficiency, relative growth rate and biomass allocation in invasive and native competitors. Additionally, a potential allelopathic effect of mulching with invasive Prunus serotina leaves on native Quercus petraea growth and photosynthesis was tested. The effect of light environment on leaf absorbed light energy partitioning and photosynthetic characteristics was more pronounced than the effects of interspecific competition and allelopathy. The quantum yield of PSII of invasive P. serotina increased in the presence of a competitor, indicating a higher plasticity in energy partitioning for the invasive over the native Q. petraea, giving it a competitive advantage. The most striking difference between the two study species was the higher crown-level net CO 2 assimilation rates (A crown ) of P. serotina compared with Q. petraea. At the juvenile life stage, higher relative growth rate and higher biomass allocation to foliage allowed P. serotina to absorb and use light energy for photosynthesis more efficiently than Q. petraea. Species-specific strategies of growth, biomass allocation, light energy partitioning and photosynthetic efficiency varied with the light environment and gave an advantage to the invader over its native competitor in competition for light. However, higher biomass allocation to roots in Q. petraea allows for greater belowground competition for water and nutrients as compared to P. serotina. This niche differentiation may compensate for the lower aboveground competitiveness of the native species and explain its ability to co-occur with the invasive competitor in natural forest settings.

  9. Effects of sand burial on survival, growth, gas exchange and biomass allocation of Ulmus pumila seedlings in the Hunshandak Sandland, China.

    Science.gov (United States)

    Shi, L; Zhang, Z J; Zhang, C Y; Zhang, J Z

    2004-10-01

    In the last decade, the number of young plants of Ulmus pumila in the Hunshandak Sandland has decreased sharply because of severe sand burial, and their ecological protective function has been weakened. In order to develop an understanding of the tolerance of U. pumila to sand burial and to suggest reasonable measures to protect the sparse-elm-grassland ecosystem, the effects of burial on the survival, growth, photosynthesis and biomass allocation in U. pumila were studied. Seedlings were buried at five different depths in pot experiments: no burial (control), partial burial (33 % and 67 % stem height), and complete burial (100 % and 133 % stem height). Growth analyses and measurements of photosynthesis were carried after the plants had been uncovered. All the plants survived partial burial, but about 30 % and 80 % of the seedlings died as a result of the 100 % and 133 % sand burial treatments, respectively. The numbers of newly produced leaves and branches, and the height of the stems of the seedlings in the 33 % and 67 % burial treatments during the period of the experiment were significantly greater than those in the control. Furthermore, net photosynthetic rate, transpiration rate and water use efficiency were also elevated by the partial burial, but not affected by burial time. This might be attributed to the increased root length, which improved water acquisition. The biomass and biomass allocation of the seedlings were significantly changed by the burial treatments and burial times. The biomass was enhanced by partial burial but was reduced by complete burial at each burial time. However, the biomass allocation was not significantly changed by the 33 % and 67 % sand burial treatments 2 or 4 weeks following the burial. Ulmus pumila was shown to be tolerant to partial sand burial, but must be protected from complete burial.

  10. Tree Biomass Allocation and Its Model Additivity for Casuarina equisetifolia in a Tropical Forest of Hainan Island, China.

    Directory of Open Access Journals (Sweden)

    Yang Xue

    Full Text Available Casuarina equisetifolia is commonly planted and used in the construction of coastal shelterbelt protection in Hainan Island. Thus, it is critical to accurately estimate the tree biomass of Casuarina equisetifolia L. for forest managers to evaluate the biomass stock in Hainan. The data for this work consisted of 72 trees, which were divided into three age groups: young forest, middle-aged forest, and mature forest. The proportion of biomass from the trunk significantly increased with age (P<0.05. However, the biomass of the branch and leaf decreased, and the biomass of the root did not change. To test whether the crown radius (CR can improve biomass estimates of C. equisetifolia, we introduced CR into the biomass models. Here, six models were used to estimate the biomass of each component, including the trunk, the branch, the leaf, and the root. In each group, we selected one model among these six models for each component. The results showed that including the CR greatly improved the model performance and reduced the error, especially for the young and mature forests. In addition, to ensure biomass additivity, the selected equation for each component was fitted as a system of equations using seemingly unrelated regression (SUR. The SUR method not only gave efficient and accurate estimates but also achieved the logical additivity. The results in this study provide a robust estimation of tree biomass components and total biomass over three groups of C. equisetifolia.

  11. Tree Biomass Allocation and Its Model Additivity for Casuarina equisetifolia in a Tropical Forest of Hainan Island, China

    Science.gov (United States)

    Xue, Yang; Yang, Zhongyang; Wang, Xiaoyan; Lin, Zhipan; Li, Dunxi; Su, Shaofeng

    2016-01-01

    Casuarina equisetifolia is commonly planted and used in the construction of coastal shelterbelt protection in Hainan Island. Thus, it is critical to accurately estimate the tree biomass of Casuarina equisetifolia L. for forest managers to evaluate the biomass stock in Hainan. The data for this work consisted of 72 trees, which were divided into three age groups: young forest, middle-aged forest, and mature forest. The proportion of biomass from the trunk significantly increased with age (Pbiomass of the branch and leaf decreased, and the biomass of the root did not change. To test whether the crown radius (CR) can improve biomass estimates of C. equisetifolia, we introduced CR into the biomass models. Here, six models were used to estimate the biomass of each component, including the trunk, the branch, the leaf, and the root. In each group, we selected one model among these six models for each component. The results showed that including the CR greatly improved the model performance and reduced the error, especially for the young and mature forests. In addition, to ensure biomass additivity, the selected equation for each component was fitted as a system of equations using seemingly unrelated regression (SUR). The SUR method not only gave efficient and accurate estimates but also achieved the logical additivity. The results in this study provide a robust estimation of tree biomass components and total biomass over three groups of C. equisetifolia. PMID:27002822

  12. Tree Biomass Allocation and Its Model Additivity for Casuarina equisetifolia in a Tropical Forest of Hainan Island, China.

    Science.gov (United States)

    Xue, Yang; Yang, Zhongyang; Wang, Xiaoyan; Lin, Zhipan; Li, Dunxi; Su, Shaofeng

    2016-01-01

    Casuarina equisetifolia is commonly planted and used in the construction of coastal shelterbelt protection in Hainan Island. Thus, it is critical to accurately estimate the tree biomass of Casuarina equisetifolia L. for forest managers to evaluate the biomass stock in Hainan. The data for this work consisted of 72 trees, which were divided into three age groups: young forest, middle-aged forest, and mature forest. The proportion of biomass from the trunk significantly increased with age (Pbiomass of the branch and leaf decreased, and the biomass of the root did not change. To test whether the crown radius (CR) can improve biomass estimates of C. equisetifolia, we introduced CR into the biomass models. Here, six models were used to estimate the biomass of each component, including the trunk, the branch, the leaf, and the root. In each group, we selected one model among these six models for each component. The results showed that including the CR greatly improved the model performance and reduced the error, especially for the young and mature forests. In addition, to ensure biomass additivity, the selected equation for each component was fitted as a system of equations using seemingly unrelated regression (SUR). The SUR method not only gave efficient and accurate estimates but also achieved the logical additivity. The results in this study provide a robust estimation of tree biomass components and total biomass over three groups of C. equisetifolia.

  13. Biomass

    International Nuclear Information System (INIS)

    Hernandez, L.A.

    1998-01-01

    Biomass constitutes the energetic form more important and of greater potential after solar energy (source of origin), being consumed in direct form through the combustion, or indirectly through the fossil fuels (those which originates) or by means of different technical of thermochemical and of biochemistry for its conversion and utilization. The current document describes the origin and the energetic characteristics of biomass, its energetic and environmental importance for a developing Country as Colombia, its possibilities of production and the technologies developed for its utilization and transformation, mainly, of the residual biomass

  14. [Aboveground biomass and nutrient distribution patterns of larch plantation in a montane region of eastern Liaoning Province, China].

    Science.gov (United States)

    Yan, Tao; Zhu, Jiao-Jun; Yang, Kai; Yu, Li-Zhong

    2014-10-01

    Larch is the main timber species of forest plantations in North China. Imbalance in nutrient cycling in soil emerged due to single species composition and mono system structure of plantation. Thus it is necessary to grasp its biomass and nutrients allocation for scientific management and nutrient cycling studies of larch plantation. We measured aboveground biomass (stem, branch, bark and leaf) and nutrient concentrations (C, N, P, K, Ca, Mg, Fe, Mn, Cu and Zn), and analyzed the patterns of accumulation and distribution of 19-year-old larch plantation with diameter at breast height of 12. 8 cm, tree height of 15. 3 m, and density of 2308 trees · hm(-2), in a montane region of eastern Liaoning Province, China. The results showed that aboveground biomass values were 70.26 kg and 162.16 t · hm(-2) for the individual tree of larch and the stand, respectively. There was a significant difference between biomass of the organs, and decreased in the order of stem > branch > bark > leaf. Nutrient accumulation was 749.94 g and 1730.86 kg · hm(-2) for the individual tree of larch and the stand, respectively. Nutrient accumulation of stem was significantly higher than that of branch, bark and leaf, whether it was macro-nutrient or micro-nutrient. Averagely, 749.94 g nutrient elements would be removed from the system when a 19-year-old larch tree was harvested. If only the stem part was removed from the system, the removal of nutrient elements could be reduced by 40.7%.

  15. Preferential allocation, physio-evolutionary feedbacks, and the stability and environmental patterns of mutualism between plants and their root symbionts.

    Science.gov (United States)

    Bever, James D

    2015-03-01

    The common occurrence of mutualistic interactions between plants and root symbionts is problematic. As the delivery of benefit to hosts involves costs to symbionts, symbionts that provide reduced benefit to their host are expected to increase in frequency. Plants have been shown to allocate preferentially to the most efficient symbiont and this preferential allocation may stabilize the mutualism. I construct a general model of the interactive feedbacks of host preferential allocation and the dynamics of root symbiont populations to evaluate the stability of nutritional mutualisms. Preferential allocation can promote the evolution of mutualism even when the cost to the symbiont is very large. Moreover, the physiological plasticity of preferential allocation likely leads to coexistence of beneficial and nonbeneficial symbionts. For arbuscular mycorrhizal fungi, which facilitate plant uptake of phosphorus (P), the model predicts greater P transfer from these fungi per unit carbon invested with decreasing concentrations of soil P and with increasing concentrations of atmospheric CO2 , patterns that have been observed in laboratory and field studies. This framework connects physiological plasticity in plant allocation to population processes that determine mutualism stability and, as such, represents a significant step in understanding the stability and environmental patterns in mutualism. © 2015 The Author. New Phytologist © 2015 New Phytologist Trust.

  16. Experimental sand burial affects seedling survivorship, morphological traits, and biomass allocation of Ulmus pumila var. sabulosa in the Horqin Sandy Land, China

    Science.gov (United States)

    Tang, Jiao; Busso, Carlos Alberto; Jiang, Deming; Musa, Ala; Wu, Dafu; Wang, Yongcui; Miao, Chunping

    2016-07-01

    As a native tree species, Ulmus pumila var. sabulosa (sandy elm) is widely distributed in the Horqin Sandy Land, China. However, seedlings of this species have to withstand various depths of sand burial after emergence because of increasing soil degradation, which is mainly caused by overgrazing, climate change, and wind erosion. An experiment was conducted to evaluate the changes in its survivorship, morphological traits, and biomass allocation when seedlings were buried at different burial depths: unburied controls and seedlings buried vertically up to 33, 67, 100, or 133 % of their initial mean seedling height. The results showed that partial sand burial treatments (i.e., less than 67 % burial) did not reduce seedling survivorship, which still reached 100 %. However, seedling mortality increased when sand burial was equal to or greater than 100 %. In comparison with the control treatment, seedling height and stem diameter increased at least by 6 and 14 % with partial burial, respectively. In the meantime, seedling taproot length, total biomass, and relative mass growth rates were at least enhanced by 10, 15.6, and 27.6 %, respectively, with the partial sand burial treatment. Furthermore, sand burial decreased total leaf area and changed biomass allocation in seedlings, partitioning more biomass to aboveground organs (e.g., leaves) and less to belowground parts (roots). Complete sand burial after seedling emergence inhibited its re-emergence and growth, even leading to death. Our findings indicated that seedlings of sandy elm showed some resistance to partial sand burial and were adapted to sandy environments from an evolutionary perspective. The negative effect of excessive sand burial after seedling emergence might help in understanding failures in recruitments of sparse elm in the study region.

  17. Research and evaluation of biomass resources/conversion/utilization systems (market/experimental analysis for development of a data base for a fuels from biomass model. Volume I. Biomass allocation model. Technical progress report for the period ending September 30, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Y.K.; Chen, H.T.; Helm, R.W.; Nelson, E.T.; Shields K.J.

    1980-01-01

    A biomass allocation model has been developed to show the most profitable combination of biomass feedstocks thermochemical conversion processes, and fuel products to serve the seasonal conditions in a regional market. This optimization model provides a tool for quickly calculating the most profitable biomass missions from a large number of potential biomass missions. Other components of the system serve as a convenient storage and retrieval mechanism for biomass marketing and thermochemical conversion processing data. The system can be accessed through the use of a computer terminal, or it could be adapted to a portable micro-processor. A User's Manual for the system has been included in Appendix A of the report. The validity of any biomass allocation solution provided by the allocation model is dependent on the accuracy of the data base. The initial data base was constructed from values obtained from the literature, and, consequently, as more current thermochemical conversion processing and manufacturing costs and efficiencies become available, the data base should be revised. Biomass derived fuels included in the data base are the following: medium Btu gas low Btu gas, substitute natural gas, ammonia, methanol, electricity, gasoline, and fuel oil. The market sectors served by the fuels include: residential, electric utility, chemical (industrial), and transportation. Regional/seasonal costs and availabilities and heating values for 61 woody and non-woody biomass species are included. The study has included four regions in the United States which were selected because there was both an availability of biomass and a commercial demand for the derived fuels: Region I: NY, WV, PA; Region II: GA, AL, MS; Region III: IN, IL, IA; and Region IV: OR, WA.

  18. Modeling banded vegetation patterns in semiarid regions: Interdependence between biomass growth rate and relevant hydrological processes

    Science.gov (United States)

    Ursino, N.

    2007-04-01

    Vegetation patterns, such as regular spots and bands, have been observed in arid and semiarid lands. One of the most common explanations for vegetation banding is that the homogeneous steady state solution of soil moisture and vegetation biomass density balance, expressed in the form of a bucket model, may be unstable under conditions of scarce mean annual rainfall. Even though the theory seems to support our intuitive explanation of the phenomenon, there are still unresolved questions concerning soil parameterization, relevant hydrological processes, and the way plant physiology should be modeled in arid and semiarid environments where vegetation patterns have been observed. This paper examines the interrelation between hydrological processes and plant physiology. The biomass growth rate resembles plant physiology within the bucket model and determines the survival plant strategy given a limited soil moisture availability. The fact that very different hypotheses concerning the biomass growth rate have been formulated has not yet been given the important consideration it deserves. Different models for vegetation banding will be considered here. They are formulated by introducing different growth rates within the same soil moisture and vegetation balance equations. Linear stability analysis and numerical integration of the different models showed some relevant interrelation between hydrological and physiological features. It was demonstrated that the relation between biomass growth rate and biomass density determines which hydrological process enables vegetation pattern initiation. The discussion of this result leads to a critical review of previously published hypotheses on plant physiology and hydrological processes inducing vegetation organization.

  19. Patterns of daily allocation of sleep periods: a case study in an Amazonian riverine community.

    Science.gov (United States)

    Aguiar, G F; da Silva, H P; Marques, N

    1991-01-01

    Few works already carried out have examined the relative role of genetic and external factors on the determination of the rhythmicity of the human sleep/wake cycle. In order to make a preliminary approach in this field, we investigated the diversity of patterns of allocation of sleep periods among 29 families living at the Combu Island, a socioculturally very homogeneous human group of the Brazilian Amazon. The individuals were interviewed through a questionnaire designed by Horne and Ostberg (1976), with the language of the questions adjusted to the way-of-life of the riverine people. A large predominance of the morning type was observed (95.35%), what constitutes a strong deviation in relation to other populations studied, suggesting the occurrence of a masking effect. The individual scores presented a positive correlation with the age (r = 0.31; p less than 0.01), and a significant intersexual difference was also verified (t = 3.08; p less than 0.01). This intersex difference is explained, in part, by analyzing the socioeconomic patterns of the community. The offspring/parent regression of the individual scores indicated a low dependency between genitors and their direct descendents (p greater than 0.7), and the estimative of heritability obtained (0.14) is artificial, since the offspring/mother and offspring/midparent regression coefficients were negative. Statistically non-significant coefficients of correlation and/or regression showed a highly randomic populational distribution of scores for the Horne-Ostberg's test. Such findings suggest that the intensity of the masking over the sleep/wake cycle varies among human populations, and that the individual tendency towards morningness/eveningness is strongly related to sociocultural factors.

  20. Can liming change root anatomy, biomass allocation and trace element distribution among plant parts of Salix × smithiana in trace element-polluted soils?

    Science.gov (United States)

    Vondráčková, Stanislava; Tlustoš, Pavel; Száková, Jiřina

    2017-08-01

    Willows (Salix spp.) are considered to be effective for the phytoremediation of trace elements from contaminated soils, but their efficiency is limited in heavily polluted soils because of poor growth. Liming can be a desirable measure to decrease the plant availability of elements, resulting in improved plant development. Notably, large root area and maximum soil penetration are basic parameters that improve the efficiency of phytoremediation. The impact of soil chemical properties on willow root anatomy and the distribution of trace elements below-ground have rarely been studied. The effect of liming on root parameters, biomass allocation and trace element distribution in non-harvestable (coarse roots, fine roots, stumps) and harvestable plant parts (twigs and leaves) of Salix × smithiana was assessed at the end of a 4-year pot experiment with two trace element-polluted soils that differed in terms of soil pH. Stump biomass predominated in weakly acidic soil. In neutral soil, the majority of biomass was located in fine roots and stumps; the difference from other plant parts was minor. Trace elements were the most concentrated in fine roots. Translocation to above-ground biomass increased as follows: Pb roots roots). Lime application decreased the concentrations of mobile Cd and Zn and related levels in plants, improved biomass production and root parameters and increased the removal of all trace elements in weakly acidic soil. None or minimum differences in the monitored parameters were recorded for dolomite treatments in both soils. The dose and source of liming had crucial effects on root anatomy. Growing willows in limed trace element-polluted soils is a suitable measure for combination of two remediation strategies, i.e. phytoextraction of Cd and Zn and assisted phytostabilization of As and Pb.

  1. Two mire species respond differently to enhanced ultraviolet-B radiation: effects on biomass allocation and root exudation

    DEFF Research Database (Denmark)

    Rinnan, Riikka Tiivi Mariisa; Gehrke, Carola; Michelsen, Anders

    2006-01-01

    •  Increased ultraviolet-B (UV-B) radiation arising from stratospheric ozone depletion may influence soil microbial communities via effects on plant carbon allocation and root exudation. •  Eriophorum angustifolium and Narthecium ossifragum plants, grown in peatland mesocosms consisting of Sphagnum...

  2. Plasticity in Meristem Allocation as an Adaptive Strategy of a Desert Shrub under Contrasting Environments

    Directory of Open Access Journals (Sweden)

    Weiwei She

    2017-11-01

    Full Text Available The pattern of resource allocation to reproduction vs. vegetative growth is a core component of a plant’s life-history strategy. Plants can modify their biomass allocation patterns to adapt to contrasting environments. Meristems can have alternative fates to commit to vegetative growth, reproduction, or remaining inactive (dormant or senescent/dead. However, knowledge about whether meristem fates can interpret adaptive changes in biomass allocation remains largely unknown. We measured aboveground plant biomass (a proxy of plant size and meristem number of a dominant shrub Artemisia ordosica in three populations occupying different habitats in the Mu Us Desert of northern China. Size-dependent biomass allocation and meristem allocation among habitats were compared. The size-dependent biomass allocation and meristem allocation of A. ordosica strongly varied across habitats. There were significant positive linear relationships between meristem allocation and biomass allocation in all habitats, indicating that meristem allocation is an indicator of the estimated resource allocation to reproductive and vegetative organs in this species. Plasticity in meristem allocation was more likely caused by larger individuals having less active meristems due to environmental stress. Vegetative meristems (VM were likely more vulnerable to environmental limitation than reproductive ones, resulting in the ratio of resource investment between vegetative and reproductive functions exhibiting plasticity in different habitats. A. ordosica invested a higher fraction of its resource to reproduction in the adverse habitat, while more resource to vegetative growth in the favorable habitat. A. ordosica adopts different resource allocation patterns to adapt to contrasting habitat conditions through altering its meristem fates. Our results suggest that the arid-adapted shrub A. ordosica deactivates more VM than reproductive ones to hedge against environmental stress

  3. Seasonal variations of vegetation patterns and biomass constituents in the rocky eulittoral of Helgoland

    Science.gov (United States)

    Munda, I. M.; Markham, J. W.

    1982-06-01

    Seasonal changes in vegetation patterns and biomass of benthic algae were recorded over a 14-month period in the rocky eulittoral of the North Sea island of Helgoland. The area is characterized by the dominance of Fucus serratus throughout most of the eulittoral and this is reflected in higher biomass of F. serratus ranged seasonally from 4.3 kg to 15 kg m-2 in the center of its extensive distribution. Biomass was also recorded monthly, when the plants were present, for Blidingia spp., Enteromorpha spp., Ulva lactuca, Fucus spiralis, F. vesiculosus, Porphyra linearis, P. umbilicalis, Chondrus crispus, Corallina officinalis, Dumontia incrassata, Petalonia fascia, P. zosterifolia and Scytosiphon lomentaria. New generations of several species which reappeared after a destructive winter storm showed a higher protein content than in the previous year. The winter and early spring flora of Helgoland shows several resemblances in species composition to the summer flora of Scandinavia.

  4. Lipid-rich and protein-poor carbon allocation patterns of phytoplankton in the northern Chukchi Sea, 2011

    Science.gov (United States)

    Yun, Mi Sun; Joo, Hui Tae; Park, Jung Woo; Kang, Jae Joong; Kang, Sung-Ho; Lee, Sang H.

    2018-04-01

    The carbon allocations of phytoplankton into different photosynthetic end products (lipids, LMWM, polysaccharides, and proteins) were determined to understand physiological conditions of phytoplankton in the northern Chukchi Sea during the Korean Arctic expedition, 2011, using the 13C isotope tracer technique. The carbon allocation rates of lipids, LMWM, polysaccharides, and proteins were 0.00009-0.00062 h-1, 0.00001-0.00049 h-1, 0.00001-0.00025 h-1, and 0.00001-0.00062 h-1 within the euphotic depths from surface to 1% light depths during our cruise period, respectively. Significant relationships between protein production rates and chlorophyll a concentrations (large and total) were found in this study. Moreover, we found a significant negative relationship between lipid production rates and ammonium concentrations. These relationships match well with the previous results for environmental/physiological conditions for phytoplankton growth. Overall, phytoplankton allocated more photosynthetic carbon into lipids (42.5 ± 17.7%) whereas relatively lower to proteins (20.4 ± 15.5%) in this study. The lipid-rich and protein-poor allocation patterns in this study suggest that phytoplankton in the northern Chukchi Sea were in a stationary growth phase under nutrient deficient condition based on biological and environmental conditions observed during our study period. Based on comparison with the previous studies in the northern Bering Sea and southern Chukchi Sea, we found that the photosynthetic carbon allocation patterns depending on physiological status of phytoplankton under the different growth and/or nutrient conditions could be largely vary at different regions in the Arctic Ocean. More intensive research on the physiological status of phytoplankton is further required to determine how phytoplankton response to the changing environmental conditions and consequently how they impact on higher trophic levels in marine ecosystems in the Arctic Ocean.

  5. Preference and consumption pattern of biomass fuel in some disregarded villages of Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Jashimuddin, M.; Masum, K.M.; Salam, M.A. [Institute of Forestry and Environmental Sciences, Chittagong University, Chittagong 4331 (Bangladesh)

    2006-05-15

    Consumer's preference and consumption pattern of biomass fuel, fuel types and energy use category has been studied in the disregarded villages of Bangladesh. The study was conducted both in the inland and island areas. Biomass energy in the study area was used in domestic cooking, tea stalls, brickfields, bakeries, paddy parboiling and pottery. Assessment of consumption in domestic cooking was done by means of multistage random sampling and that in the tea stalls, brickfields, bakeries, paddy parboiling and pottery by means of complete enumeration of the sampling unit. Based on the homestead size respondents were categorized into small, medium and large and a total of 60 homesteads (30 from inland and another 30 from island areas), 20 from each category were selected randomly for the study. The study revealed that natural gas was quite absent and stems, branches and twigs, leaves of trees, agricultural residues, shell and coir of coconut, saw dust, brush wood, rhizomes of bamboo, and cowdung were the biomass fuel used by the respondent. Nine fuelwood species were identified as the most preferred in the study area. Consumption pattern was mostly traditional. Each year preceding the rainy season cyclonic action damages a large quantity of biomass energy sources. Though at the initial stage of rainy season (April-May) there remain a more or less good collection of fuelwood to the user as the byproduct of cyclones and storms, the last part of the rainy season (July-August) was identified as the fuel shortage period. (author)

  6. Modeling Relationships between Shrubland Biomass and Pattern Water Use Efficiency Along Semi-Arid Climatic Gradients

    Science.gov (United States)

    Shoshany, Maxim

    2014-05-01

    A new model is presented that represents the effect of the shrub patches' spatial arrangement on their water use efficiency and biomass productivity in water limited ecosystems. The model utilizes an Edge Ratio parameterization calculated as the ratio between vegetation edge area and the total vegetation area. Pattern Water Use Efficiency employs the following relationships: 1. Water Use efficiency would be directly related to shrub Cover Fraction. 2. Water Use Efficiency would be Inversely related to amount of edge areas (Edge Ratio). 3. The effect of Edge would be Inversely related to shrub cover fraction. 4. The effect of Edge would be Inversely related to the shrubs' height. Pattern Water Use Efficiency than modulates the use of precipitation in producing biomass. Preliminary assessment of the new model was achieved by comparing its results with biomass as extracted from high-resolution imagery based on allometric equations for 18 sites along a climatic gradient between Mediterranean and arid regions in Central Israel. In the next phase, the model is modified to allow its implementation with Landsat Imagery. This form of the model facilitated wide regional mapping of shrublands' biomass. Such mapping is fundamental for assessing the impacts of climate change on ecosystems productivity in desert fringe ecosystems.

  7. Patterns of biomass and carbon distribution across a chronosequence of Chinese pine (Pinus tabulaeformis forests.

    Directory of Open Access Journals (Sweden)

    Jinlong Zhao

    Full Text Available Patterns of biomass and carbon (C storage distribution across Chinese pine (Pinus tabulaeformis natural secondary forests are poorly documented. The objectives of this study were to examine the biomass and C pools of the major ecosystem components in a replicated age sequence of P. tabulaeformis secondary forest stands in Northern China. Within each stand, biomass of above- and belowground tree, understory (shrub and herb, and forest floor were determined from plot-level investigation and destructive sampling. Allometric equations using the diameter at breast height (DBH were developed to quantify plant biomass. C stocks in the tree and understory biomass, forest floor, and mineral soil (0-100 cm were estimated by analyzing the C concentration of each component. The results showed that the tree biomass of P. tabulaeformis stands was ranged from 123.8 Mg·ha-1 for the young stand to 344.8 Mg·ha-1 for the mature stand. The understory biomass ranged from 1.8 Mg·ha-1 in the middle-aged stand to 3.5 Mg·ha-1 in the young stand. Forest floor biomass increased steady with stand age, ranging from 14.9 to 23.0 Mg·ha-1. The highest mean C concentration across the chronosequence was found in tree branch while the lowest mean C concentration was found in forest floor. The observed C stock of the aboveground tree, shrub, forest floor, and mineral soil increased with increasing stand age, whereas the herb C stock showed a decreasing trend with a sigmoid pattern. The C stock of forest ecosystem in young, middle-aged, immature, and mature stands were 178.1, 236.3, 297.7, and 359.8 Mg C ha-1, respectively, greater than those under similar aged P. tabulaeformis forests in China. These results are likely to be integrated into further forest management plans and generalized in other contexts to evaluate C stocks at the regional scale.

  8. Responses in chemical traits and biomass allocation of Arundo donax L. to deficit resources in the establishment year

    Directory of Open Access Journals (Sweden)

    Antonio Pompeiano

    2013-12-01

    Full Text Available A large expansion in renewable energy production is underway with an increasing focus on sustainable second-generation biofuels. Fast growing rhizomatous perennial grasses are leading candidates for lignocellulosic feedstock thanks to their positive energy balance, and low ecological/agro-management demands. Biomass accumulation is favored by the efficient use of available resources. The aim of this study was to identify which accumulation processes were most affected in the establishment year of a giant reed (Arundo donax L. field crop grown under water and N deficiencies. The relative plasticity of growth of A. donax in response to various levels of resource availability was evaluated. A field scale experiment was carried out, and treatments were arranged as a randomized complete block, strip-plot design with irrigation treatments as the main plot factor and pre-planting N rate as the sub-plot factor. Biometric relationships between variables were assessed to understand how agro-management factors influence the above ground biomass of giant reed, as well as yield over time. Evidence is presented indicating that growth is strongly enhanced by water availability (+97% dry weight biomass. Changes in composition were not significant within or among fixed treatments, rather changes were observed over time. A high content of glucans and xylans were detected from early stage, and as the mobilization of minerals increased, lignin content significantly increased as well (from 12% to 36% w/w. These results suggest that an increase in the growth of A. donax in the establishment year is accomplished by a limited use of the water input

  9. Loblolly Pine Growth Patterns on Reclaimed Mineland: Allometry, Biomass, and Volume

    Directory of Open Access Journals (Sweden)

    Jeremy Priest

    2015-10-01

    Full Text Available Surface lignite coal mines in east Texas are commonly reforested using loblolly pine (Pinus taeda L. following mining and reclamation activities. Due to the nature of such an extreme disturbance, altered growth patterns, growth rates, and productivity could be expected. We destructively sampled above- and belowground tissue to develop prediction equations specific to these sites. These prediction equations differed statistically from those found in the literature regarding unmined land. At the stand level, biomass and volume productivity appeared similar with young stands on reclaimed mineland performing slightly poorer than similarly managed unmined sites. Allometric partitioning of above- and belowground biomass differed statistically from the unmined allometric model previously studied. The allometric pattern on reclaimed mineland indicated greater partitioning of biomass belowground for young stands of low quadratic mean diameter relative to unmined stands. Older stands on reclaimed mineland exhibited no allometric partitioning differences from unmined stands, indicating the normal allometric pattern is resumed for stands greater than 10 years of age.

  10. Effects of simulated root herbivory and fertilizer application on growth and biomass allocation in the clonal perennialSolidago canadensis.

    Science.gov (United States)

    Schmid, B; Miao, S L; Bazzaz, F A

    1990-08-01

    Compensatory growth in response to simulated belowground herbivory was studied in the old-field clonal perennialSolidago canadensis. We grew rootpruned plants and plants with intact root systems in soil with or without fertilizer. For individual current shoots (aerial shoot with rhizome and roots) and for whole clones the following predictions were tested: a) root removal is compensated by increased root growth, b) fertilizer application leads to increased allocation to aboveground plant organs and increased leaf turnover, c) effects of fertilizer application are reduced in rootpruned plants. When most roots (90%) were removed current shoots quickly restored equilibrium between above-and belowground parts by compensatory belowground growth whereas the whole clone responded with reduced aboveground growth. This suggests that parts of a clone which are shared by actively growing shoots act as a buffer that can be used as source of material for compensatory growth in response to herbivory. Current shoots increased aboveground mass and whole clones reduced belowground mass in response to fertilizer application, both leading to increased allocation to aboverground parts. Also with fertilizer application both root-pruned and not root-pruned plants increased leaf and shoot turnover. Unfertilized plants, whether rootpruned or not, showed practically no aboveground growth and very little leaf and shoot turnover. Effects of root removal were as severe or more severe under conditions of high as under conditions of low nutrients, suggesting that negative effects of belowground herbivory are not ameliorated by abundant nutrients. Root removal may negate some effects of fertilizer application on the growth of current shoots and whole clones.

  11. Partição da biomassa e qualidade da forragem de Bahiagrass: Paspalun notatum cv. pensacola no centro-norte da Flórida = Biomass allocation and forage quality in a pensacola Bahiagrass pasture in north central Florida

    Directory of Open Access Journals (Sweden)

    Marcia Mascarenhas Grise

    2006-10-01

    Full Text Available Visando medir efeitos do manejo da Bahiagrass cv. pensacola (Paspalum notatum Flüggeé na repartição de biomassa (kg ha-1 das folhas+colmos, serrapilheira, raízes+rizomas, e valor nutritivo da forragem, foi instalado um experimento próximo a Gainesville, Flórida,EUA. Tratamentos: três manejos contínuos (não intensivo, moderadamente intensivo, altamente intensivo, recebendo 40, 120, e 360 kg N ha -1 ano-1 e com lotação de 1,2; 2,4 e 3,6 UA ha-1, respectivamente e um tratamento de manejo rotacionado (7 dias de pastejo e 21 dias de descanso, recebendo 360 kg N ha-1 ano-1 e 3,6 UA ha-1 (1 U A= 500 kg. A biomassa de raízes+rizomas foi superior a de folhas+colmos. Não houve efeito dos tratamentos na biomassa de raízes+rizomas. A biomassa de raízes+rizomas decresceu durante a estação de pastejo. A maior intensidade de manejo dos tratamentos altamente intensivo e rotacionado resultou em maior biomassa de folhas+colmos. A relação raiz/parte aérea decresceu com a intensificação do manejo. A biomassa de serrapilheira foi superior a de folhas+colmos nos tratamentos altamente intensivo e rotacionado, privilegiando a ciclagem de nutrienes via excreção animal. Os tratamentos não afetaram a FDN nem a DIVMO da forragem, masintensificação do manejo tende a elevar a DIV MO da forragem.This experiment evaluated a pensacola Bahiagrass pasture (Paspalum notatum Flüggeé. It was conducted near Gainesville, Florida, U SA, to measure the effect of pasture management on biomass allocation (kg ha -1 of herbage, litter, root+rhizome, as well as forage quality. Treatments were three continuously stocked (low, moderate, and high,receiving 40, 120, and 360 kg N fertilizer ha -1 yr-1and with stocking rates of 1.2, 2.4, and 3.6 AU ha-1, respectively and one rotationally stocked (RS; 7 -d grazing and 21-d rest periods; N rate of 360 kg ha-1 yr-1, 1 AU = 500 kg pasture. The root+rhizome biomass was 4 to 12 times greater than herbage biomass. There was

  12. Global patterns of socioeconomic biomass flows in the year 2000. A comprehensive assessment of supply, consumption and constraints

    International Nuclear Information System (INIS)

    Krausmann, Fridolin; Erb, Karl-Heinz; Gingrich, Simone; Lauk, Christian; Haberl, Helmut

    2008-01-01

    Human use of biomass has become a major component of the global biogeochemical cycles of carbon and nitrogen. The use of land for biomass production (e.g. cropland) is among the most important pressures on biodiversity. At the same time, biomass is indispensable for humans as food, animal feed, raw material and energy source. In order to support research into these complex issues, we here present a comprehensive assessment of global socioeconomic biomass harvest, use and trade for the year 2000. We developed country-level livestock balances and a consistent set of factors to estimate flows of used biomass not covered by international statistics (e.g. grazed biomass, crop residues) and indirect flows (i.e. biomass destroyed during harvest but not used). We found that current global terrestrial biomass appropriation amounted to 18.7 billion tonnes dry matter per year (Pg/yr) or 16% of global terrestrial NPP of which 6.6 Pg/yr were indirect flows. Only 12% of the economically used plant biomass (12.1 Pg/yr) directly served as human food, while 58% were used as feed for livestock, 20% as raw material and 10% as fuelwood. There are considerable regional variations in biomass supply and use. Distinguishing 11 world regions, we found that extraction of used biomass ranged from 0.3 to 2.8 t/ha/yr, per-capita values varied between 1.2 and 11.7 t/cap/yr (dry matter). Aggregate global biomass trade amounted to 7.5% of all extracted biomass. An analysis of these regional patterns revealed that the level of biomass use per capita is determined by historically evolved patterns of land use and population density rather than by affluence or economic development status. Regions with low population density have the highest level of per-capita biomass use, high-density regions the lowest. Livestock, consuming 30-75% of all harvested biomass, is another important factor explaining regional variations in biomass use. Global biomass demand is expected to grow during the next decades

  13. Comparison of national level biomass maps for conterminous US: understanding pattern and causes of differences

    Directory of Open Access Journals (Sweden)

    N. Neeti

    2016-08-01

    Full Text Available Abstract Background As Earth observation satellite data proliferate, so too do maps derived from them. Even when two co-located maps are produced with low overall error, the spatial distribution of error may not be the same. Increasingly, methods will be needed to understand differences among purportedly similar products. For this study, we have used the four aboveground biomass (AGB maps for conterminous US generated under NASA’s Carbon Monitoring System. We have developed systematic approach to (1 assess both the absolute accuracy of individual maps and assess the spatial patterns of agreement among maps, and (2 investigate potential causes of the spatial structure of agreement among maps to gain insight into reliability of methodological choices in map making. Results The comparison of the four biomass maps with FIA based total biomass estimates at national scale suggest that all the maps have higher biomass estimate compared to FIA. When the four maps were compared among each other, the result shows that the maps S and K have more similar spatial structure whereas the maps K and W have more similar absolute values. Although the maps K and W were generated using completely different methodological workflow, they agree remarkably. All the maps did well in the dominant forest type with maximum agreement between them. The comparison of difference between maps S and K with regional maps suggests that these maps were able to capture the disturbance and not so much regrowth pattern. Conclusions The study provides a comprehensive systematic approach to compare and evaluate different real data products using examples of four AGB maps. Although ostensibly the four maps map the same variable, they have different spatial distribution at different scale. Except the 2003 map, one can use other maps at the coarser spatial resolution. Finally, the disparate information available through different maps indicates a need for a temporal framework for

  14. GIS Methodology for Location of Biomass Power Plants Via Multi -Criteria Evaluation and Network Analysis. Location-Allocation Models for Forest Biomass Use; Metodologia SIG para la Localizacion de Centrales de Biomasa mediante Evaluacion Multicriterio y Analisis de Redes. Modelos de Localizacion-Asignacion para el Aprovechamiento de Biomasa Forestal

    Energy Technology Data Exchange (ETDEWEB)

    Paz, C. de la; Dominguez, J.; Perez, M. E.

    2013-02-01

    The main purpose of this study is to find optimal areas for the installation of Biomass Plants for electric generation and grid connected. In order to achieve this goal, a methodology based on Multi-Criteria Evaluation (MCE) and implemented by means a Geographic Information System (GIS) has been developed. Factors and restrictions for biomass resource and power plants location of biomass have been obtained through the dataset. The methodology output includes maps of greater aptitude areas for resource use (forest biomass available), as well as suitable locations for the placement of Forest Biomass facilities. Both cartographic products have been related by means Network Analysis. It generates Location-Allocation Models which allows locating Forest Biomass Facilities according with an optimization of the supply chain from the resource areas. (Author)

  15. Landscape Patterns of Wood Density and Aboveground Biomass Along a Tropical Elevation Gradient in Costa Rica

    Science.gov (United States)

    Robinson, C. M.

    2015-12-01

    This research sought to understand how tree wood density and taxonomic diversity relate to topography and three-dimensional vegetation structure in the tropical montane forest of Braulio Carrillo National Park in Costa Rica. The study utilized forest inventory and botanical data from twenty 1-ha plots ranging from 55 m to 2800 m above sea level and remote sensing data from an airborne lidar sensor (NASA's Land, Vegetation, and Ice Sensor [LVIS]) to quantify variations in forest structure. There is growing evidence that ecosystem structure may help to control the functional variations across landscapes. This study relates patterns of tree functional wood density and alpha diversity to three-dimensional structure using remote sensing observations of forest structure. We were able to test the effect of the gradient on wood density measured from collected tree cores and on the subsequent aboveground biomass estimations. We sought to determine if there was a significant pattern of wood density across the altitudinal gradient, which has implications for conservation of both ecosystem services and biodiversity. We also wanted to determine how many random individuals could be sampled to accurately estimate aboveground biomass in a one-hectare plot. Our results indicate that there is a strong relationship between LVIS-derived forest 3D-structure and alpha diversity, likely controlled by variations in abiotic factors and topography along the elevation. Using spatial analysis with the aid of remote sensing data, we found patterns along the environmental gradients defining species composition and forest structure. Wood density values were found to vary significantly from database values for the same species. This variation in tree growth has repercussions on overall forest structure, and subsequent carbon estimates extrapolated from field measurements. Because these wood density values are directly tied to biomass estimates, it is possible that carbon storage has been

  16. Linking root hydraulic properties to carbon allocation patterns in annual plant

    Science.gov (United States)

    Hosseini, A.; Ewers, B. E.; Adjesiwor, A. T.; Kniss, A. R.

    2017-12-01

    Incorporation of root structure and function into biophysical models is an important tool to predict plant water and nutrient uptake from the soil, plant carbon (C) assimilation, partitioning and release to the soils. Most of the models describing root water uptake (RWU) are based on semi-empirical (i.e. built on physiological hypotheses, but still combined with empirical functions) approaches and hydraulic parameters involved are hardly available. Root conductance is essential to define the interaction between soil-to-root and canopy-to-atmosphere. Also root hydraulic limitations to water flow can impact gas exchange rates and plant biomass partitioning. In this study, sugar beet (B. vulgaris) seeds under two treatments, grass (Kentucky bluegrass) and no grass (control), were planted in 19 L plastic buckets in June 2016. Photosynthetic characteristics (e.g. gas exchange and chlorophyll fluorescence), leaf morphology and anatomy, root morphology and above and below ground biomass of the plants was monitored at 15, 30, 50, 70 and 90 days after planting (DAP). Further emphasis was placed on the limits to water flow by coupling of hydraulic conductance (k) whole root-system with water relation parameters and gas exchange rates in fully established plants.

  17. Distribution pattern of picoplankton carbon biomass linked to mesoscale dynamics in the southern gulf of Mexico during winter conditions

    Science.gov (United States)

    Linacre, Lorena; Lara-Lara, Rubén; Camacho-Ibar, Víctor; Herguera, Juan Carlos; Bazán-Guzmán, Carmen; Ferreira-Bartrina, Vicente

    2015-12-01

    In order to characterize the carbon biomass spatial distribution of autotrophic and heterotrophic picoplankton populations linked to mesoscale dynamics, an investigation over an extensive open-ocean region of the southern Gulf of Mexico (GM) was conducted. Seawater samples from the mixed layer were collected during wintertime (February-March 2013). Picoplankton populations were counted and sorted using flow cytometry analyses. Carbon biomass was assessed based on in situ cell abundances and conversion factors from the literature. Approximately 46% of the total picoplankton biomass was composed of three autotrophic populations (Prochlorococcus, Synechococcus, and pico-eukaryotes), while 54% consisted of heterotrophic bacteria populations. Prochlorococcus spp. was the most abundant pico-primary producer (>80%), and accounted for more than 60% of the total pico-autotrophic biomass. The distribution patterns of picoplankton biomass were strongly associated with the mesoscale dynamics that modulated the hydrographic conditions of the surface mixed layer. The main features of the carbon distribution pattern were: (1) the deepening of picoplankton biomass to layers closer to the nitracline base in anticyclonic eddies; (2) the shoaling of picoplankton biomass in cyclonic eddies, constraining the autoprokaryote biomasses to the upper layers, as well as accumulating the pico-eukaryote biomass in the cold core of the eddies; and (3) the increase of heterotrophic bacteria biomass in frontal regions between counter-paired anticyclonic and cyclonic eddies. Factors related to nutrient preferences and light conditions may as well have contributed to the distribution pattern of the microbial populations. The findings reveal the great influence of the mesoscale dynamics on the distribution of picoplankton populations within the mixed layer. Moreover, the significance of microbial components (especially Prochlorococcus) in the southern GM during winter conditions was revealed

  18. Long-term patterns in tropical reforestation: plant community composition and aboveground biomass accumulation.

    Science.gov (United States)

    Marín-Spiotta, E; Ostertag, R; Silver, W L

    2007-04-01

    Primary tropical forests are renowned for their high biodiversity and carbon storage, and considerable research has documented both species and carbon losses with deforestation and agricultural land uses. Economic drivers are now leading to the abandonment of agricultural lands, and the area in secondary forests is increasing. We know little about how long it takes for these ecosystems to achieve the structural and compositional characteristics of primary forests. In this study, we examine changes in plant species composition and aboveground biomass during eight decades of tropical secondary succession in Puerto Rico, and compare these patterns with primary forests. Using a well-replicated chronosequence approach, we sampled primary forests and secondary forests established 10, 20, 30, 60, and 80 years ago on abandoned pastures. Tree species composition in all secondary forests was different from that of primary forests and could be divided into early (10-, 20-, and 30-year) vs. late (60- and 80-year) successional phases. The highest rates of aboveground biomass accumulation occurred in the first 20 years, with rates of C sequestration peaking at 6.7 +/- 0.5 Mg C x ha(-1) x yr(-1). Reforestation of pastures resulted in an accumulation of 125 Mg C/ha in aboveground standing live biomass over 80 years. The 80 year-old secondary forests had greater biomass than the primary forests, due to the replacement of woody species by palms in the primary forests. Our results show that these new ecosystems have different species composition, but similar species richness, and significant potential for carbon sequestration, compared to remnant primary forests.

  19. Growth, biomass allocation and photosynthesis of Rolandra fruticosa (asteraceae in response to shade Crescimento, alocação de biomassa e fotossíntese de Rolandra fruticosa (asteraceae em resposta ao sombreamento

    Directory of Open Access Journals (Sweden)

    Moacyr B. Dias-Filho

    2000-01-01

    Full Text Available The effects of shade on growth, biomass allocation patterns and photosynthetic response was examined for Rolandra fruticosa (L. Kuntze, a common perennial weed shrub in cultivated pastures and agricultural areas of Brazilian Amazonia, for plants grown in full sunlight and those shaded to 30 % of full sunlight over a 34-d period. Specific leaf area and leaf area ratio were higher for shade plants during all the experimental period. Shade plants allocated significantly less biomass to root tissue than sun plants and relative growth rate was higher in sun plants. Sun leaves had significantly higher dark respiration and light saturated rates of photosynthesis than shade leaves. The apparent quantum efficiency was higher for shade leaves, while light compensation point was higher for sun leaves. These results are discussed in relation to their ecological and weed management implications.Estudou-se o efeito do sombreamento nocrescimento, alocação de carbono e respostas fotossintéticas de Rolandra fruticosa (L. Kuntze, uma planta daninha de porte arbustivo, comum em áreas de pastagem e agrícolas da Amazônia Brasileira, submetida a condições de pleno sol e a 70 % de interceptação da luz solar, durante 34 dias. A área foliar específica e a razão de área foliar foram maiores nas plantas sombreadas durante todo o período experimental. Plantas sombreadas alocaram menor quantidade de biomassa para as raízes, quando comparadas às plantas de sol e a taxa de crescimento relativo foi maior para as plantas de sol. A respiração no escuro e a taxa de fotossíntese máxima foram maiores para as folhas de plantas não sombreadas. A eficiência quântica aparente foi maior para as folhas de plantas sombreadas, enquanto que o ponto de compensação de luz foi maior para folhas a pleno sol. Esses resultados são discutidos com relação as suas importâncias ecológica e de manejo.

  20. Growth and biomass allocation of the C4 grasses Brachiaria brizantha and B. humidicola under shade Crescimento e alocação de biomassa nas gramíneas C4 Brachiaria brizantha e B. humidicola sob sombreamento

    Directory of Open Access Journals (Sweden)

    MOACYR BERNARDINO DIAS-FILHO

    2000-12-01

    Full Text Available The growth and biomass allocation responses of the tropical forage grasses Brachiaria brizantha cv. Marandu and B. humidicola were compared for plants grown outdoors, in pots, in full sunlight and those shaded to 30% of full sunlight over a 30day period. The objective was to evaluate the acclimation capacity of these species to low light. Both species were able to quickly develop phenotypic adjustments in response to low light. Specific leaf area and leaf area ratio were higher for low-light plants during the entire experimental period. Low-light plants allocated significantly less biomass to root and more to leaf tissue than high-light plants. However, the biomass allocation pattern to culms was different for the two species under low light: it increased in B. brizantha, but decreased in B. humidicola, probably as a reflection of the growth habits of these species. Relative growth rate and tillering were higher in high-light plants. Leaf elongation rate was significantly increased on both species under low light; however, the difference between treatments was higher in B. brizantha. These results are discussed in relation to the pasture management implications.O crescimento e a alocação de biomassa das gramíneas forrageiras tropicais Brachiaria brizantha cv. Marandu e B. humidicola foram comparados, em plantas cultivadas em vasos, a pleno sol e a 70% de interceptação da luz solar, durante um período de 30 dias. O objetivo foi avaliar a capacidade de aclimatação dessas espécies ao sombreamento. Ambas as espécies mostraram-se capazes de desenvolver rapidamente ajustes fenotípicos em resposta ao sombreamento. A área foliar específica e a razão de área foliar foram maiores durante todo o período experimental, nas plantas cultivadas à sombra. As plantas sombreadas alocaram significativamente menos biomassa nas raízes e mais nas folhas do que as plantas cultivadas à sombra. No entanto, a alocação de biomassa no colmo foi

  1. Variation in Seed Quality, Seedling Growth and Biomass Allocation of One-year-old Siberian Larch ( Larix sibirica Ledeb. Seedlings Grown in Different Conditions from Diverse Seed Sources of Mongolia

    Directory of Open Access Journals (Sweden)

    Nyam-Osor Batkhuu

    2006-12-01

    Full Text Available The rehabilitation of degraded forests in Mongolia showed very low success and the total area reforested successfully represents only 5% of the total forest lost. One of the reasons for such poor results may be low quality of planting stock due to the poor quality of seeds. The objectives of this study were to determine seed source variation in seed quality, to examine their growth and biomass allocation in one-year-old seedlings of Siberian larch from diverse seed sources, and to select the most promising seed sources for reforestation of degraded forest lands in Mongolia. Siberian larch seedlings from eight geographically different seed sources were grown at an open nursery and in greenhouse nursery conditions, and seedlings were subjected to growth and biomass allocation measurements at the end of the fi rst growing season. It was found that there were signi fi cant differences in seed quality, growth and biomass allocation among the seed sources in both growth conditions. Overall, Sources No.3 (Tuul river and No.4 (Mungun showed the best growth performances and biomass accumulation at open nursery and greenhouse nursery conditions, respectively. Source No.1 (Ovorkhangai had the lowest performances in both growth conditions for all measured variables. On the other hand, seedlings grown in the greenhouse nursery conditions had more intensive growth and accumulated more biomass compared to seedlings grown in open nursery conditions. However, the proportion of biomass of the roots at open nursery grown seedlings was higher than that of greenhouse grown seedlings, which may indicate a more promising survival rate after fi eld transplanting.

  2. Patterns of energy allocation to reproduction in three Amazonian fish species

    Directory of Open Access Journals (Sweden)

    Rodrigo N. dos Santos

    2010-03-01

    Full Text Available The study considered the influence of the hydrological cycle and gonadal development on the accumulation and use of energy in three fish species from an Amazonian flooded area. Fishes were sampled over a 24 hour period at monthly intervals between July 2004 and June 2005 using gillnets of different mesh sizes. Body cavity fat and gonadosomatic indices were determined, as well as energy content of gonads and muscles. Amongst the studied species, different means of energy allocation for reproduction were found: Acestrorhynchus falcirostris allocate energy from body cavity fat to its gonads; Pygocentrus nattereri uses mainly energy accumulated in the muscles for the process of gonadal maturation; and Hoplosternum littorale uses energy accumulated in their muscles and body cavity fat for reproductive processes. It is quite clear that the flood pulse regulates the gain and use of the energy reserves in fishes from the Amazonian floodplain.O presente estudo considerou a influência do ciclo hidrológico e maturação gonadal no acúmulo e utilização da energia em três espécies de peixes, numa área de planície de inundação amazônica. As amostras foram obtidas mensalmente durante o período de julho de 2004 a junho de 2005, utilizando redes de emalhar com vários tamanhos de malhas, durante 24 horas. O índice de gordura cavitária, índice gonadossomático, e teor energético dos músculos e gônadas foram analisados. Dentre as espécies analisadas, foram detectados diferentes padrões de alocação de energia: Acestrorhynchus falcirostris aloca energia das reservas de gordura cavitária para as gônadas; Pygocentrus nattereri utiliza energia dos músculos para este fim e Hoplosternum littorale, além da gordura cavitária, utiliza também energia acumulada nos músculos para realização dos processos reprodutivos. Ficou evidente que o pulso de inundação exerce forte influência no acúmulo e utilização das reservas energéticas dos

  3. Natural (13) C distribution in oil palm (Elaeis guineensis Jacq.) and consequences for allocation pattern.

    Science.gov (United States)

    Lamade, Emmanuelle; Tcherkez, Guillaume; Darlan, Nuzul Hijri; Rodrigues, Rosario Lobato; Fresneau, Chantal; Mauve, Caroline; Lamothe-Sibold, Marlène; Sketriené, Diana; Ghashghaie, Jaleh

    2016-01-01

    Oil palm has now become one of the most important crops, palm oil representing nearly 25% of global plant oil consumption. Many studies have thus addressed oil palm ecophysiology and photosynthesis-based models of carbon allocation have been used. However, there is a lack of experimental data on carbon fixation and redistribution within palm trees, and important C-sinks have not been fully characterized yet. Here, we carried out extensive measurement of natural (13) C-abundance (δ(13) C) in oil palm tissues, including fruits at different maturation stages. We find a (13) C-enrichment in heterotrophic organs compared to mature leaves, with roots being the most (13) C-enriched. The δ(13) C in fruits decreased during maturation, reflecting the accumulation in (13) C-depleted lipids. We further used observed δ(13) C values to compute plausible carbon fluxes using a steady-state model of (13) C-distribution including metabolic isotope effects ((12) v/(13) v). The results suggest that fruits represent a major respiratory loss (≈39% of total tree respiration) and that sink organs such as fruits are fed by sucrose from leaves. That is, glucose appears to be a quantitatively important compound in palm tissues, but computations indicate that it is involved in dynamic starch metabolism rather that C-exchange between organs. © 2015 John Wiley & Sons Ltd.

  4. Looking for age-related growth decline in natural forests: unexpected biomass patterns from tree rings and simulated mortality.

    Science.gov (United States)

    Foster, Jane R; D'Amato, Anthony W; Bradford, John B

    2014-05-01

    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 a census tree-ring data set from eight temperate forest types to reconstruct stand-level biomass increments (in Minnesota, USA). We compared growth patterns among mortality models, forest types and stands. Timing of peak biomass growth varied significantly among mortality models, peaking 20-30 years earlier when mortality was random with respect to tree growth and size, than when mortality favored slow-growing individuals. Random or u-shaped mortality (highest in small or large trees) produced peak growth 25-30% higher than the surviving tree sample alone. Growth trends for even-aged, monospecific Pinus banksiana or Acer saccharum forests were similar to the early peak and decline expectation. However, we observed continually increasing biomass growth in older, low-productivity forests of Quercus rubra, Fraxinus nigra, and Thuja occidentalis. Tree-ring reconstructions estimated annual changes in live biomass growth and identified more diverse development patterns than previous methods. These detailed, long-term patterns of biomass development are crucial for detecting recent growth responses to global change and modeling future forest dynamics.

  5. Allometric analysis of the effects of density on reproductive allocation and Harvest Index in 6 varieties of wheat (Triticum)

    DEFF Research Database (Denmark)

    Qin, Xiao-liang; Weiner, Jacob; Qi, Lin

    2013-01-01

    Plants produce biomass and then allocate some of this biomass to reproduction. The pattern of reproductive allocation is an important aspect of a plant’s reproductive strategy in nature and is closely linked to yield and Harvest Index in cereal crops. Recent research has concluded that reproductive...... allocation should be analyzed and interpreted allometrically because ratios or fractions such as Reproductive Effort or Harvest Index are size dependent. We investigated reproductive allocation of individuals in 6 varieties of Triticum (wheat) grown at a wide range of densities. We harvested leaves, stems...... when there is large variation in productivity among individuals, locations or years....

  6. How evolving heterogeneity distributions of resource allocation strategies shape mortality patterns.

    Directory of Open Access Journals (Sweden)

    Yann Le Cunff

    Full Text Available It is well established that individuals age differently. Yet the nature of these inter-individual differences is still largely unknown. For humans, two main hypotheses have been recently formulated: individuals may experience differences in aging rate or aging timing. This issue is central because it directly influences predictions for human lifespan and provides strong insights into the biological determinants of aging. In this article, we propose a model which lets population heterogeneity emerge from an evolutionary algorithm. We find that whether individuals differ in (i aging rate or (ii timing leads to different emerging population heterogeneity. Yet, in both cases, the same mortality patterns are observed at the population level. These patterns qualitatively reproduce those of yeasts, flies, worms and humans. Such findings, supported by an extensive parameter exploration, suggest that mortality patterns across species and their potential shapes belong to a limited and robust set of possible curves. In addition, we use our model to shed light on the notion of subpopulations, link population heterogeneity with the experimental results of stress induction experiments and provide predictions about the expected mortality patterns. As biology is moving towards the study of the distribution of individual-based measures, the model and framework we propose here paves the way for evolutionary interpretations of empirical and experimental data linking the individual level to the population level.

  7. Red:far-red light conditions affect the emission of volatile organic compounds from barley (Hordeum vulgare), leading to altered biomass allocation in neighbouring plants.

    Science.gov (United States)

    Kegge, Wouter; Ninkovic, Velemir; Glinwood, Robert; Welschen, Rob A M; Voesenek, Laurentius A C J; Pierik, Ronald

    2015-05-01

    Volatile organic compounds (VOCs) play various roles in plant-plant interactions, and constitutively produced VOCs might act as a cue to sense neighbouring plants. Previous studies have shown that VOCs emitted from the barley (Hordeum vulgare) cultivar 'Alva' cause changes in biomass allocation in plants of the cultivar 'Kara'. Other studies have shown that shading and the low red:far-red (R:FR) conditions that prevail at high plant densities can reduce the quantity and alter the composition of the VOCs emitted by Arabidopsis thaliana, but whether this affects plant-plant signalling remains unknown. This study therefore examines the effects of far-red light enrichment on VOC emissions and plant-plant signalling between 'Alva' and 'Kara'. The proximity of neighbouring plants was mimicked by supplemental far-red light treatment of VOC emitter plants of barley grown in growth chambers. Volatiles emitted by 'Alva' under control and far-red light-enriched conditions were analysed using gas chromatography-mass spectrometry (GC-MS). 'Kara' plants were exposed to the VOC blend emitted by the 'Alva' plants that were subjected to either of the light treatments. Dry matter partitioning, leaf area, stem and total root length were determined for 'Kara' plants exposed to 'Alva' VOCs, and also for 'Alva' plants exposed to either control or far-red-enriched light treatments. Total VOC emissions by 'Alva' were reduced under low R:FR conditions compared with control light conditions, although individual volatile compounds were found to be either suppressed, induced or not affected by R:FR. The altered composition of the VOC blend emitted by 'Alva' plants exposed to low R:FR was found to affect carbon allocation in receiver plants of 'Kara'. The results indicate that changes in R:FR light conditions influence the emissions of VOCs in barley, and that these altered emissions affect VOC-mediated plant-plant interactions. © The Author 2015. Published by Oxford University Press on

  8. Trophic diversity, size and biomass spectrum of Bay of Bengal nematodes: A study case on depth and latitudinal patterns

    Science.gov (United States)

    Ansari, Kapuli Gani Mohamed Thameemul; Lyla, Somasundharanair; Khan, Syed Ajmal; Bhadury, Punyasloke

    2017-09-01

    Depth and latitudinal patterns of nematode functional attributes were investigated from 35 stations of Bay of Bengal (BoB) continental shelf. We aim to address whether depth and latitudinal variations can modify nematode community structure and their functional attributes (trophic diversity, size and biomass spectra). Global trend of depth and latitudinal related variations have also been noticed from BoB shelf in terms of nematode abundance and species richness, albeit heterogeneity patterns were encountered in functional attributes. Index of trophic diversity values revealed higher trophic diversity across the BoB shelf and suggested variety of food resource availability. However, downstream analysis of trophic status showed depth and latitude specific patterns but not reflected in terms of size and biomass spectrum. The peaks at different positions clearly visualized heterogeneity in distribution patterns for both size and biomass spectrum and also there was evidence of availability of diversified food resources. Nematode biomass spectra (NBS) constructed for nematode communities showed shift in peak biomass values towards lower to moderate size classes particularly in shallower depth but did not get reflected in latitudes. However, Chennai and Parangipettai transects demonstrated shift in peak biomass values towards higher biomass classes explaining the representation of higher nematode abundance. Our findings concluded that depth and latitudes are physical variables; they may not directly affect nematode community structure and functional attributes but they might influence the other factors such as food availability, sediment deposition and settlement rate. Our observations suggest that the local factors (seasonal character) of phytodetrital food flux can be very important for shaping the nematode community structure and success of nematode functional heterogeneity patterns across the Bay of Bengal shelf.

  9. Time allocation shifts and pollutant exposure due to traffic congestion: an analysis using the national human activity pattern survey.

    Science.gov (United States)

    Zhang, Kai; Batterman, Stuart A

    2009-10-15

    Traffic congestion increases air pollutant exposures of commuters and urban populations due to the increased time spent in traffic and the increased vehicular emissions that occur in congestion, especially "stop-and-go" traffic. Increased time in traffic also decreases time in other microenvironments, a trade-off that has not been considered in previous time activity pattern (TAP) analyses conducted for exposure assessment purposes. This research investigates changes in time allocations and exposures that result from traffic congestion. Time shifts were derived using data from the National Human Activity Pattern Survey (NHAPS), which was aggregated to nine microenvironments (six indoor locations, two outdoor locations and one transport location). After imputing missing values, handling outliers, and conducting other quality checks, these data were stratified by respondent age, employment status and period (weekday/weekend). Trade-offs or time-shift coefficients between time spent in vehicles and the eight other microenvironments were then estimated using robust regression. For children and retirees, congestion primarily reduced the time spent at home; for older children and working adults, congestion shifted the time spent at home as well as time in schools, public buildings, and other indoor environments. Changes in benzene and PM(2.5) exposure were estimated for the current average travel delay in the U.S. (9 min day(-1)) and other scenarios using the estimated time shifts coefficients, concentrations in key microenvironments derived from the literature, and a probabilistic analysis. Changes in exposures depended on the duration of the congestion and the pollutant. For example, a 30 min day(-1) travel delay was determined to account for 21+/-12% of current exposure to benzene and 14+/-8% of PM(2.5) exposure. The time allocation shifts and the dynamic approach to TAPs improve estimates of exposure impacts from congestion and other recurring events.

  10. Differences in Patterns of Reproductive Allocation between the Sexes in Nicrophorus orbicollis.

    Science.gov (United States)

    Smith, Ashlee N; Creighton, J Curtis; Belk, Mark C

    2015-01-01

    Organisms are selected to maximize lifetime reproductive success by balancing the costs of current reproduction with costs to future survival and fecundity. Males and females typically face different reproductive costs, which makes comparisons of their reproductive strategies difficult. Burying beetles provide a unique system that allows us to compare the costs of reproduction between the sexes because males and females are capable of raising offspring together or alone and carcass preparation and offspring care represent the majority of reproductive costs for both sexes. Because both sexes perform the same functions of carcass preparation and offspring care, we predict that they would experience similar costs and have similar life history patterns. In this study we assess the cost of reproduction in male Nicrophorus orbicollis and compare to patterns observed in females. We compare the reproductive strategies of single males and females that provided pre- and post-hatching parental care. There is a cost to reproduction for both males and females, but the sexes respond to these costs differently. Females match brood size with carcass size, and thus maximize the lifetime number of offspring on a given size carcass. Males cull proportionately more offspring on all carcass sizes, and thus have a lower lifetime number of offspring compared to females. Females exhibit an adaptive reproductive strategy based on resource availability, but male reproductive strategies are not adaptive in relation to resource availability.

  11. Pattern and levels of spending allocated to HIV prevention programs in low- and middle-income countries.

    Science.gov (United States)

    Amico, Peter; Gobet, Benjamin; Avila-Figueroa, Carlos; Aran, Christian; De Lay, Paul

    2012-03-21

    AIDS continues to spread at an estimated 2.6 new million infections per year, making the prevention of HIV transmission a critical public health issue. The dramatic growth in global resources for AIDS has produced a steady scale-up in treatment and care that has not been equally matched by preventive services. This paper is a detailed analysis of how countries are choosing to spend these more limited prevention funds. We analyzed prevention spending in 69 low- and middle-income countries with a variety of epidemic types, using data from national domestic spending reports. Spending information was from public and international sources and was analyzed based on the National AIDS Spending Assessment (NASA) methods and classifications. Overall, prevention received 21% of HIV resources compared to 53% of funding allocated to treatment and care. Prevention relies primarily on international donors, who accounted for 65% of all prevention resources and 93% of funding in low-income countries. For the subset of 53 countries that provided detailed spending information, we found that 60% of prevention resources were spent in five areas: communication for social and behavioral change (16%), voluntary counselling and testing (14%), prevention of mother-to-child transmission (13%), blood safety (10%) and condom programs (7%). Only 7% of funding was spent on most-at-risk populations and less than 1% on male circumcision. Spending patterns did not consistently reflect current evidence and the HIV specific transmission context of each country. Despite recognition of its importance, countries are not allocating resources in ways that are likely to achieve the greatest impact on prevention across all epidemic types. Within prevention spending itself, a greater share of resources need to be matched with interventions that approximate the specific needs and drivers of each country's epidemic.

  12. Pattern and levels of spending allocated to HIV prevention programs in low- and middle-income countries

    Directory of Open Access Journals (Sweden)

    Amico Peter

    2012-03-01

    Full Text Available Abstract Background AIDS continues to spread at an estimated 2.6 new million infections per year, making the prevention of HIV transmission a critical public health issue. The dramatic growth in global resources for AIDS has produced a steady scale-up in treatment and care that has not been equally matched by preventive services. This paper is a detailed analysis of how countries are choosing to spend these more limited prevention funds. Methods We analyzed prevention spending in 69 low- and middle-income countries with a variety of epidemic types, using data from national domestic spending reports. Spending information was from public and international sources and was analyzed based on the National AIDS Spending Assessment (NASA methods and classifications. Results Overall, prevention received 21% of HIV resources compared to 53% of funding allocated to treatment and care. Prevention relies primarily on international donors, who accounted for 65% of all prevention resources and 93% of funding in low-income countries. For the subset of 53 countries that provided detailed spending information, we found that 60% of prevention resources were spent in five areas: communication for social and behavioral change (16%, voluntary counselling and testing (14%, prevention of mother-to-child transmission (13%, blood safety (10% and condom programs (7%. Only 7% of funding was spent on most-at-risk populations and less than 1% on male circumcision. Spending patterns did not consistently reflect current evidence and the HIV specific transmission context of each country. Conclusions Despite recognition of its importance, countries are not allocating resources in ways that are likely to achieve the greatest impact on prevention across all epidemic types. Within prevention spending itself, a greater share of resources need to be matched with interventions that approximate the specific needs and drivers of each country's epidemic.

  13. PATTERNS OF PREY BIOMASS CONSUMPTION BY SMALL ODONTOCETES IN THE NORTHEASTERN COAST OF VENEZUELA

    Directory of Open Access Journals (Sweden)

    Lenin E. Oviedo Correa

    2011-07-01

    Full Text Available Trophic relationships are conditioned by population dynamics of interacting species in the community (species present, food web connections among them, and the strength of interactions, and on the consequences of these species interactions depend various ecosystem processes such as productivity and nutrient flux. Odontocetes target a wide range of prey items and are adapted to feeding at different depths. The aim of this report is to describe the patterns of prey consumption by small odontocetes, incorporating natural predatory patterns into a potential management scheme of strategic food sources, for both human and marine predators. Using the geo-statistical analysis tool of ArcGIS 9.2, maps illustrating the intensity and location of prey consumption were made for species with a sighting index (SPUE > 0.15. The biomass consumption emphasized the differences in habitat use by species. The trends in distribution of prey biomass removal by odontocetes particularly suggest a stratification of prey consumption primarily in shelf waters, with a prey biomass that is comprised basically by demersal fish and small pelagics (including Sardinella aurita, and into transition-oceanic depths where most of the predatory pattern would potentially rely on pelagic - mesopelagic squid and myctophids. Overall the spatial tendencies in regionalization presented in this contribution will serve as a base-line to assess ecosystem health and evaluate management scenarios.   Las relaciones tróficas son reguladas por la dinámica poblacional de las especies que interactúan dentro de la comunidad (especies presentes, conexiones interespecíficas, y nivel de interacción y de las consecuencias de esas interacciones para procesos del ecosistema como la productividad y el flujo de nutrientes. El objetivo de este reporte es evaluar el patrón de consumo de biomasa por odontocetos de menor tamaño en la costa Nororiental de Venezuela, incorporando patrones de depredaci

  14. Whole-plant C allocation priorities: do secondary metabolites and VOCs matter?

    Science.gov (United States)

    Hartmann, Henrik; Huang, Jianbei; Forkelova, Lenka; Behrendt, Thomas; Reichelt, Michael; Hammerbacher, Almuth

    2017-04-01

    Whole-plant carbon (C) allocation is a critical issue for understanding plant functioning and has been studied for many decades. Plants fix CO2 from the atmosphere and partition the resulting photosynthetic products (carbohydrates) among several functional pools including growth of structural and reproductive biomass, metabolic processes like respiration but also for the synthesis of secondary metabolites promoting defense and communication. Allocation to secondary metabolites is conceptually viewed as a trade-off between growth and defense. Plants either invest carbohydrates to produce biomass which may be lost - at least partially -to herbivory or they increase allocation to secondary metabolites to deter herbivores from consuming existing biomass. While conceptually intuitive, trade-off hypotheses all suffer from one important shortcoming: the whole-plant carbon balance, critical for determining trade-off relationships, is usually unknown. In the research group on Plant Allocation, we manipulate and measure the whole-plant carbon balance in different species and use tracers to investigate carbon fluxes through the plant and into functional allocation pools. Inducing carbon limitation by reducing atmospheric [CO2] allows us to infer allocation priorities. In this presentation I will show several examples of studies on whole-plant carbon allocation patterns in different plant species. These investigations include assessments of different functional pools like growth, storage, secondary metabolites and volatile emissions as well as the underlying phytohormonal patterns and show that allocation to secondary metabolites and volatiles has a high priority in the whole-plant carbon balance.

  15. Sorption-reduction coupled gold recovery process boosted by Pycnoporus sanguineus biomass: Uptake pattern and performance enhancement via biomass surface modification.

    Science.gov (United States)

    Shi, Chaohong; Zhu, Nengwu; Kang, Naixin; Wu, Pingxiao; Zhang, Xiaoping; Zhang, Yanhong

    2017-09-01

    Biorecovery is emerging as a promising process to retrieve gold from secondary resources. The present study aimed to explore the uptake pattern of Pycnoporus sanguineus biomass for gold, identify the effective functional groups in gold recovery process, and thus further intensify the process via microbial surface modification. Results showed that P. sanguineus biomass could effectively recover gold with the formation of highly crystal AuNPs without any exogeneous electron donor. Under the conditions of various initial gold concentrations (1.0, 2.0, and 3.0 mM), biomass dosage of 2.0 g/L, solution pH value of 4.0, and incubation temperature of 30°C, the uptake equilibrium established after 4, 8, and 12 h, respectively. The uptake process could be well described by pseudo-second order kinetics model (R 2  = 0.9988) and Langmuir isotherm model (R 2  = 0.9958). The maximum uptake capacity of P. sanguineus reached as high as 358.69 mg/g. Further analysis indicated that amino, carboxyl and hydroxyl groups positively contributed to the uptake process. Among them, amino group significantly favored the uptake of gold during recovery process. When P. sanguineus biomass was modified by introduction of amino group, the gold uptake process was successfully intensified by shortening the uptake period and enhancing the uptake capacity. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1314-1322, 2017. © 2017 American Institute of Chemical Engineers.

  16. Genetic architecture and temporal patterns of biomass accumulation in spring barley revealed by image analysis.

    Science.gov (United States)

    Neumann, Kerstin; Zhao, Yusheng; Chu, Jianting; Keilwagen, Jens; Reif, Jochen C; Kilian, Benjamin; Graner, Andreas

    2017-08-10

    Genetic mapping of phenotypic traits generally focuses on a single time point, but biomass accumulates continuously during plant development. Resolution of the temporal dynamics that affect biomass recently became feasible using non-destructive imaging. With the aim to identify key genetic factors for vegetative biomass formation from the seedling stage to flowering, we explored growth over time in a diverse collection of two-rowed spring barley accessions. High heritabilities facilitated the temporal analysis of trait relationships and identification of quantitative trait loci (QTL). Biomass QTL tended to persist only a short period during early growth. More persistent QTL were detected around the booting stage. We identified seven major biomass QTL, which together explain 55% of the genetic variance at the seedling stage, and 43% at the booting stage. Three biomass QTL co-located with genes or QTL involved in phenology. The most important locus for biomass was independent from phenology and is located on chromosome 7HL at 141 cM. This locus explained ~20% of the genetic variance, was significant over a long period of time and co-located with HvDIM, a gene involved in brassinosteroid synthesis. Biomass is a dynamic trait and is therefore orchestrated by different QTL during early and late growth stages. Marker-assisted selection for high biomass at booting stage is most effective by also including favorable alleles from seedling biomass QTL. Selection for dynamic QTL may enhance genetic gain for complex traits such as biomass or, in the future, even grain yield.

  17. Climate change effects on plant biomass alter dominance patterns and community evenness in an experimental old-field ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Kardol, Paul [ORNL; Campany, Courtney E [University of Tennessee, Knoxville (UTK); Souza, Lara [University of Tennessee, Knoxville (UTK); Norby, Richard J [ORNL; Weltzin, Jake [University of Tennessee, Knoxville (UTK); Classen, Aimee T [University of Tennessee, Knoxville (UTK)

    2010-01-01

    Atmospheric and climatic change can alter plant biomass production and plant community composition. However, we know little about how climate change-induced alterations in biomass production affect plant community composition. To better understand how climate change will alter both individual plant species and community biomass we manipulated atmospheric [CO2], air temperature and precipitation in a constructed old-field ecosystem. Specifically, we compared the responses of dominant and subdominant species to our treatments, and explored how changes in plant dominance patterns alter community evenness over two years. Our study resulted in four major findings: 1) All treatments, elevated [CO2], warming and increased precipitation, increased plant biomass and the effects were additive rather than interactive, 2) Plant species differed in their response to the treatments, resulting in shifts in the proportional biomass of individual species, which altered the plant community composition; however, the plant community response was largely driven by the responses of the dominant species, 3) Precipitation explained most of the variation in plant community composition among treatments, and 4) Changes in precipitation caused a shift in the dominant species proportional biomass that resulted in higher community evenness in the dry relative to wet treatments. Interestingly, compositional and evenness responses of the subdominant community to the treatments did not always follow the responses of the whole plant community. Our data suggest that changes in plant dominance patterns and community evenness are an important part of community responses to climate change, and generally, that compositional shifts can have important consequences for the functioning of terrestrial ecosystems.

  18. The morphological /settlement pattern classification of South African settlements based on a settlement catchment approach, to inform facility allocation and service delivery

    CSIR Research Space (South Africa)

    Sogoni, Z

    2016-07-01

    Full Text Available / settlement pattern classification of South African settlements based on a settlement catchment approach, to inform facility allocation and service delivery Zukisa Sogoni Planning Africa Conference 2016 4 July 2Project Focus and Background • CSIR... services. • Purpose is to support application & planning for new investment & prevent “unsustainable” investments / White elephants. 3Outputs • National set of service delivery catchments • Profile information per individual catchment • Ranking...

  19. Temperature drives global patterns in forest biomass distribution in leaves, stems, and roots

    Science.gov (United States)

    Reich, Peter B.; Lou, Yunjian; Bradford, John B.; Poorter, Hendrik; Perry, Charles H.; Oleksyn, Jacek

    2014-01-01

    Whether the fraction of total forest biomass distributed in roots, stems, or leaves varies systematically across geographic gradients remains unknown despite its importance for understanding forest ecology and modeling global carbon cycles. It has been hypothesized that plants should maintain proportionally more biomass in the organ that acquires the most limiting resource. Accordingly, we hypothesize greater biomass distribution in roots and less in stems and foliage in increasingly arid climates and in colder environments at high latitudes. Such a strategy would increase uptake of soil water in dry conditions and of soil nutrients in cold soils, where they are at low supply and are less mobile. We use a large global biomass dataset (>6,200 forests from 61 countries, across a 40 °C gradient in mean annual temperature) to address these questions. Climate metrics involving temperature were better predictors of biomass partitioning than those involving moisture availability, because, surprisingly, fractional distribution of biomass to roots or foliage was unrelated to aridity. In contrast, in increasingly cold climates, the proportion of total forest biomass in roots was greater and in foliage was smaller for both angiosperm and gymnosperm forests. These findings support hypotheses about adaptive strategies of forest trees to temperature and provide biogeographically explicit relationships to improve ecosystem and earth system models. They also will allow, for the first time to our knowledge, representations of root carbon pools that consider biogeographic differences, which are useful for quantifying whole-ecosystem carbon stocks and cycles and for assessing the impact of climate change on forest carbon dynamics.

  20. Current patterns of macroalgal diversity and biomass in northern hemisphere rocky shores.

    Directory of Open Access Journals (Sweden)

    Brenda Konar

    Full Text Available Latitudinal gradients in species abundance and diversity have been postulated for nearshore taxa but few analyses have been done over sufficiently broad geographic scales incorporating various nearshore depth strata to empirically test these gradients. Typically, gradients are based on literature reviews and species lists and have focused on alpha diversity across the entire nearshore zone. No studies have used a standardized protocol in the field to examine species density among sites across a large spatial scale while also focusing on particular depth strata. The present research used field collected samples in the northern hemisphere to explore the relationships between macroalgal species density and biomass along intertidal heights and subtidal depths and latitude. Results indicated no overall correlations between either estimates of species density or biomass with latitude, although the highest numbers of both were found at mid-latitudes. However, when strata were examined separately, significant positive correlations were found for both species numbers and biomass at particular strata, namely the intertidal ones. While the data presented in this paper have some limitations, we show that latitudinal macroalgal trends in species density and biomass do exist for some strata in the northern hemisphere with more taxa and biomass at higher latitudes.

  1. Differences in allocation patterns and in the use of distributive principles emerge from children of Brazilian parents in Brazil and in the United States

    Directory of Open Access Journals (Sweden)

    Leonardo Rodrigues Sampaio

    2015-01-01

    Full Text Available This study aimed to investigate differences in the way children in Brazil and USA allocate resources and justify their decisions in a fictional situation. The sample was composed by 178 children of Brazilian parents: 98 Brazilian, living in Brazil, and 80 American children, who had low familiarity with Brazilian culture. Participants were requested to resolve a distributive dilemma during which characters with different personal attributes reunited to a picnic in a public park. The results showed that most children preferred equality or near-equality patterns of distribution to allocate the food among the characters of the dilemma. Preference for other patterns of distribution like equity and need was related to age and nationality. Also, children who used equality as justification for their distributions were more consistent (that is, they distributed the food using an allocation system who matched their justification than children who used other types of justifications. Results are discussed in light of recent works on sharing and processes of socialization during childhood.

  2. Effects of fertilization and competition on plant biomass allocation and internal resources: Does Plantago lanceolata follow the rules of economic theory?

    Czech Academy of Sciences Publication Activity Database

    Janeček, Štěpán; Patáčová, E.; Klimešová, Jitka

    2014-01-01

    Roč. 49, č. 1 (2014), s. 49-64 ISSN 1211-9520 R&D Projects: GA ČR GA526/09/0963; GA ČR GA526/07/0808 Institutional research plan: CEZ:AV0Z60050516 Institutional support: RVO:67985939 Keywords : allocation * Plantago lanceolata * plasticity Subject RIV: EH - Ecology, Behaviour Impact factor: 1.778, year: 2014

  3. Impacts of communal fuelwood extraction on lidar-estimated biomass patterns of savanna woodlands

    CSIR Research Space (South Africa)

    Wessels, Konrad J

    2012-07-01

    Full Text Available Approximately 54% of rural households in South Africa continue to use wood as their main source of energy, mainly for cooking and heating. The provision of biomass by savanna woodlands is thus of considerable value to rural households and therefore...

  4. Leaf allocation patterns and 13C and 15N natural abundances of tropical lianas (Passiflora sp.) as dependent on external climbing support.

    Science.gov (United States)

    Werth, Martin; Spiegel, Ann-Kathrin; Kazda, Marian

    2013-01-01

    The transformation from self-supporting lianas to host-supported climbing lianas is related to re-allocation of biomass and nutrients among plant organs. Therefore, first, variations in leaf mass per area (LMA), leaf carbon and nitrogen allocation and (13)C and (15)N natural abundances were analysed among three tropical Passiflora species (P. edulis, P. ligularis, and P. tripartita) in a greenhouse study. Second, the influence of a climbing support was considered for each species and parameter. P. ligularis leaves were most enriched in (13)C in both treatments when compared with the other two species. This enrichment was caused by a high LMA, which is related to a high internal resistance to CO(2) diffusion. For P. edulis and P. tripartita, δ(13)C was additionally increasing with nitrogen content per area. Generally, there were no differences when considering carbon and nitrogen allocation to leaves of host-supported and self-supporting lianas. The only hints towards increased investment into leaves after the transition from self-supporting to host-supported stages could be seen by a trend to increased leaf areas and masses. δ(13)C values of supported P. edulis or P. tripartita plants were significantly increasing faster than those of non-supported plants once the interactions of leaf mass or nitrogen content per area were accounted for. Hence, the offer of a climbing support had only a minor impact on δ(13)C or δ(15)N values in vitro, but this could be different with increasing age of lianas in vivo.

  5. The effect of topography on arctic-alpine aboveground biomass and NDVI patterns

    Science.gov (United States)

    Riihimäki, Henri; Heiskanen, Janne; Luoto, Miska

    2017-04-01

    Topography is a key factor affecting numerous environmental phenomena, including Arctic and alpine aboveground biomass (AGB) distribution. Digital Elevation Model (DEM) is a source of topographic information which can be linked to local growing conditions. Here, we investigated the effect of DEM derived variables, namely elevation, topographic position, radiation and wetness on AGB and Normalized Difference Vegetation Index (NDVI) in a Fennoscandian forest-alpine tundra ecotone. Boosted regression trees were used to derive non-parametric response curves and relative influences of the explanatory variables. Elevation and potential incoming solar radiation were the most important explanatory variables for both AGB and NDVI. In the NDVI models, the response curves were smooth compared with AGB models. This might be caused by large contribution of field and shrub layer to NDVI, especially at the treeline. Furthermore, radiation and elevation had a significant interaction, showing that the highest NDVI and biomass values are found from low-elevation, high-radiation sites, typically on the south-southwest facing valley slopes. Topographic wetness had minor influence on AGB and NDVI. Topographic position had generally weak effects on AGB and NDVI, although protected topographic position seemed to be more favorable below the treeline. The explanatory power of the topographic variables, particularly elevation and radiation demonstrates that DEM-derived land surface parameters can be used for exploring biomass distribution resulting from landform control on local growing conditions.

  6. Intraseasonal patterns in coastal plankton biomass off central Chile derived from satellite observations and a biochemical model

    Science.gov (United States)

    Gomez, Fabian A.; Spitz, Yvette H.; Batchelder, Harold P.; Correa-Ramirez, Marco A.

    2017-10-01

    Subseasonal (5-130 days) environmental variability can strongly affect plankton dynamics, but is often overlooked in marine ecology studies. We documented the main subseasonal patterns of plankton biomass in the coastal upwelling system off central Chile, the southern part of the Humboldt System. Subseasonal variability was extracted from temporal patterns in satellite data of wind stress, sea surface temperature, and chlorophyll from the period 2003-2011, and from a realistically forced eddy-resolving physical-biochemical model from 2003 to 2008. Although most of the wind variability occurs at submonthly frequencies (anchovy. The wind-driven variability of chlorophyll concentration was connected to mid- and high-latitude atmospheric anomalies, which resemble disturbances with frequencies similar to the tropical Madden-Julian Oscillation.

  7. Patterns and trends of macrobenthic abundance, biomass and production in the deep Arctic Ocean

    Directory of Open Access Journals (Sweden)

    Renate Degen

    2015-08-01

    Full Text Available Little is known about the distribution and dynamics of macrobenthic communities of the deep Arctic Ocean. The few previous studies report low standing stocks and confirm a gradient with declining biomass from the slopes down to the basins, as commonly reported for deep-sea benthos. In this study, we investigated regional differences of faunal abundance and biomass, and made for the first time ever estimates of deep Arctic community production by using a multi-parameter artificial neural network model. The underlying data set combines data from recent field studies with published and unpublished data from the past 20 years, to analyse the influence of water depth, geographical latitude and sea-ice concentration on Arctic benthic communities. We were able to confirm the previously described negative relationship of macrofauna standing stock with water depth in the Arctic deep sea, while also detecting substantial regional differences. Furthermore, abundance, biomass and production decreased significantly with increasing sea-ice extent (towards higher latitudes down to values <200 ind m−2, <65 mg C m−2 and <73 mg C m−2 y−1, respectively. In contrast, stations under the seasonal ice zone regime showed much higher standing stock and production (up to 2500 mg C m−2 y−1, even at depths down to 3700 m. We conclude that particle flux is the key factor structuring benthic communities in the deep Arctic Ocean as it explains both the low values in the ice-covered Arctic basins and the higher values in the seasonal ice zone.

  8. Growth, biomass allocation and photosynthetic responses are related to intensity of root severance and soil moisture conditions in the plantation tree Cunninghamia lanceolata.

    Science.gov (United States)

    Dong, Tingfa; Duan, Baoli; Zhang, Sheng; Korpelainen, Helena; Niinemets, Ülo; Li, Chunyang

    2016-07-01

    We employed the warm temperate conifer Cunninghamia lanceolata (Lamb.) Hook. as a model of plantation forest species to investigate ecophysiological responses to root treatments (control (0%), and ∼25, 50 or 75% of the initial root mass) under well-watered and water-limited conditions. Our results indicated that total root dry mass accumulation was negatively associated with the severity of root pruning, but there was evidence of multiple compensatory responses. The plants exhibited higher instantaneous and long-term (assessed by carbon isotope composition, δ(13)C) water-use efficiency in pruning treatments, especially under low water availability. Root pruning also increased the fine root/total root mass ratio, specific root length and fine root vitality in both water availability treatments. As a result of the compensatory responses, under well-watered conditions, height, stem dry mass accumulation, leaf/fine root biomass ratio (L/FR), transpiration rate, photosynthetic capacity and photosynthetic nitrogen-use efficiency (EN) were the highest under 25% pruning. Yet, all these traits except L/FR and foliage nitrogen content were severely reduced under 75% pruning. Drought negatively affected growth and leaf gas exchange rates, and there was a greater negative effect on growth, water potential, gas exchange and EN when >25% of total root biomass was removed. The stem/aboveground mass ratio was the highest under 25% pruning in both watering conditions. These results indicate that the responses to root severance are related to the excision intensity and soil moisture content. A moderate root pruning proved to be an effective means to improve stem dry mass accumulation. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. ESG Allocations

    Data.gov (United States)

    Department of Housing and Urban Development — This report displays the Emergency Solutions Grants (ESG), formerly Emergency Shelter Grants, allocation by jurisdiction. The website allows users to look at...

  10. Global Characterization of Biomass-Burning Patterns using Satellite Measurements of Fire Radiative Energy

    Science.gov (United States)

    Ichoku, Charles; Giglio, Louis; Wooster, Martin J.; Remer, Lorraine A.

    2008-01-01

    Remote sensing is the most practical means of measuring energy release from large open-air biomass burning. Satellite measurement of fire radiative energy (FRE) release rate or power (FRP) enables distinction between fires of different strengths. Based on a 1-km resolution fire data acquired globally by the MODerate-resolution Imaging Spectro-radiometer (MODIS) sensor aboard the Terra and Aqua satellites from 2000 to 2006, instanteaneous FRP values ranged between 0.02 MW and 1866 MW, with global daily means ranging between 20 and 40 MW. Regionally, at the Aqua-MODIS afternoon overpass, the mean FRP values for Alaska, Western US, Western Australia, Quebec and the rest of Canada are significantly higher than these global means, with Quebec having the overall highest value of 85 MW. Analysis of regional mean FRP per unit area of land (FRP flux) shows that a peak fire season in certain regions, fires can be responsible for up to 0.2 W/m(sup 2) at peak time of day. Zambia has the highest regional monthly mean FRP flux of approximately 0.045 W/m(sup 2) at peak time of day and season, while the Middle East has the lowest value of approximately 0.0005 W/m(sup 2). A simple scheme based on FRP has been devised to classify fires into five categories, to facilitate fire rating by strength, similar to earthquakes and hurricanes. The scheme uses MODIS measurements of FRP at 1-km resolution as follows: catagory 1 (less than 100 MW), category 2 (100 to less than 500 MW), category 3 (500 to less than 1000 MW), category 4 (1000 to less than 1500 MW), catagory 5 (greater than or equal to 1500 MW). In most regions of the world, over 90% of fires fall into category 1, while only less than 1% fall into each of categories 3 to 5, although these proportions may differ significantly from day to day and by season. The frequency of occurence of the larger fires is region specific, and could not be explained by ecosystem type alone. Time-series analysis of the propertions of higher category

  11. Environmental patterns and biomass distribution of gelatinous macrozooplankton. Three study cases in the South-western Atlantic Ocean

    Directory of Open Access Journals (Sweden)

    H. W. Mianzan

    2000-12-01

    Full Text Available Periodic swarms or blooms of gelatinous macrozooplankton have a negative effect on many human activities such as tourism, fisheries, and industry, but for several reasons (sampling procedures, underestimation of their real abundance, etc., they have often been neglected in the local literature. The high spatial resolution exercise of the South-western Atlantic anchovy Engraulis anchoita Recruitment Project (SARP was therefore also suitable for estimating standing stocks of jelly macrozooplankton, attempting to establish particular environmental patterns exerting control on the spatial distribution of these facultative carnivorous predators in coastal frontal environments. These studies were carried out through a sampling programme on board the German R/V Meteor in three different systems, convergence and divergent, in the South-western Atlantic Ocean: Region A (42°S on the Argentine shelf, characterised by tidal mixing fronts; Region B (36°S, the freshwater outflow from Río de la Plata; and Region C (28°S, under upwelling events in subtropical waters on the Brazilian shelf. In general, a dominance of gelatinous macrozooplankton, compared with the other fraction of macrozooplankton and micronekton was observed. Mean standing stock of the gelatinous zooplankton was always greater than 50% of organic carbon (org. C in every section analysed. The lobate ctenophore Mnemiopsis leidyi dominated the zooplankton biomass in Region A, Argentina. It represented 60% of total org. C and was more abundant at the stratified zone of the front. Ctenophores were also dominant in Region B, Río de la Plata, where the related species Mnemiopsis mccradyi and the cydippid ctenophore Pleurobrachia pileus comprised 81% of total org. C. Mnemiopsis was most common in areas of vertical thermal and saline stratification, while Pleurobrachia was dominant in the less stratified areas. Gelatinous zooplankton was also the principal component of the macrozooplankton biomass

  12. Belowground carbon allocation by trees drives seasonal patterns of extracellular enzyme activities by altering microbial community composition in a beech forest soil.

    Science.gov (United States)

    Kaiser, Christina; Koranda, Marianne; Kitzler, Barbara; Fuchslueger, Lucia; Schnecker, Jörg; Schweiger, Peter; Rasche, Frank; Zechmeister-Boltenstern, Sophie; Sessitsch, Angela; Richter, Andreas

    2010-08-01

    *Plant seasonal cycles alter carbon (C) and nitrogen (N) availability for soil microbes, which may affect microbial community composition and thus feed back on microbial decomposition of soil organic material and plant N availability. The temporal dynamics of these plant-soil interactions are, however, unclear. *Here, we experimentally manipulated the C and N availability in a beech forest through N fertilization or tree girdling and conducted a detailed analysis of the seasonal pattern of microbial community composition and decomposition processes over 2 yr. *We found a strong relationship between microbial community composition and enzyme activities over the seasonal course. Phenoloxidase and peroxidase activities were highest during late summer, whereas cellulase and protease peaked in late autumn. Girdling, and thus loss of mycorrhiza, resulted in an increase in soil organic matter-degrading enzymes and a decrease in cellulase and protease activity. *Temporal changes in enzyme activities suggest a switch of the main substrate for decomposition between summer (soil organic matter) and autumn (plant litter). Our results indicate that ectomycorrhizal fungi are possibly involved in autumn cellulase and protease activity. Our study shows that, through belowground C allocation, trees significantly alter soil microbial communities, which may affect seasonal patterns of decomposition processes.

  13. Sex allocation in gynodioecious Cyananthus delavayi differs between gender morphs and soil quality.

    Science.gov (United States)

    Chen, Jianguo; Niu, Yang; Li, Zhimin; Yang, Yang; Sun, Hang

    2017-06-01

    Sex allocation in Cyananthus delavayi. Gynodioecy, where females and hermaphrodites coexist in the same natural population, is particularly suitable for predicting the ecological pressures that drive the stability of gender polymorphism. Since females have a disadvantage in that they only contribute to the next generation via ovules, they should gain an advantage via other means, of which resource allocation is an important component. Thus, to study their sex allocation is very helpful to understand how the dimorphic sexual system is maintained in natural systems. We studied the sex allocation patterns and reproductive output of the gynodioecious Cyananthus delavayi in three populations with different soil qualities (organic matter, N, P and K). The hermaphroditic flowers and pistils were much larger than those of female individuals. Although both gender morphs invested similar biomass in the pistils, females allocated more of their resource pool to the seed production, while hermaphrodites allocated more to pollinator advertisement. The pollen production of hermaphrodites did not differ between populations, suggesting that pollen production by hermaphrodites was not limited by soil nutrients. Fruit set of females, but not hermaphrodites, decreased with declining soil quality, whereas seeds per fruit of both females and hermaphrodites were highest in poor soils. Overall, this study shows that females achieve greater reproductive success by allocating more of their resource pool to enhancing seed production, which should favor their presence in gynodioecious populations. The hermaphrodites achieve reproductive success from both pollen and seed production, and unnecessarily reduce their allocation to pollen production. Soil quality should explain, at least partially, the sexual allocation patterns. Furthermore, some of our findings contradict previous hypotheses, thus adding a new example to the body of research on plant sex allocation and the development of future

  14. Alocação de biomassa e nutrientes em Heteranthera reniformis sob o efeito de N, P e K Allocation of biomass and nutrients in Heteranthera reniformis under the effect of N, P and K

    Directory of Open Access Journals (Sweden)

    V.D. Domingos

    2005-03-01

    the period of 35 days. The largest leaf areas were verified in solutions to 75% of P and 50% of N and K. The solution up to 50% of N provided the largest dried biomass of the plants. The stem contribution to the allocation of resources presented results ranging from 55.5 to 74.5% in relation to the total dry matter regarding level 0 and 75% of N. Root contribution decreased with the increase of N, P and K concentrations. The greatest root contributions were in the absence of N (26.8% and P (19.2%, which were higher in relation to their respective more concentrated levels. The contents of N, P and K corresponded to an increasing order in leaf, stem and roots, with the largest contents obtained in the range of 50 to 125 mg L-1 of N; 5 to 15 mg L-1 of P; and 100 to 150 mg L-1 of K.

  15. Biomass production and carbon storage of Populus ×canadensis ...

    African Journals Online (AJOL)

    euramericana (Dode) Guinier ex Piccarolo) clone I-214 have good potential for biomass production. The objective of the study was estimation of biomass using allometric equations and estimation of carbon allocation according to tree components.

  16. Physiological responses of two tropical weeds to shade: I. Growth and biomass allocation Respostas fisiológicas de duas plantas invasoras tropicais ao sombreamento: I. Crescimento e alocação de biomassa

    Directory of Open Access Journals (Sweden)

    Moacyr Bernardino Dias-Filho

    1999-06-01

    Full Text Available Ipomoea asarifolia (Desr. Roem. & Schultz (Convolvulaceae and Stachytarpheta cayennensis (Rich Vahl. (Verbenaceae, two weeds found in pastures and crop areas in Brazilian Amazonia, were grown in controlled environment cabinets under high (800-1000 µmol m-² s-¹ and low (200-350 µmol m-² s-¹ light regimes during a 40-day period. For both species leaf dry mass and leaf area per total plant dry mass, and leaf area per leaf dry mass were higher for low-light plants, whereas root mass per total plant dry mass was higher for high-light plants. High-light S. cayennensis allocated significantly more biomass to reproductive tissue than low-light plants, suggesting a probably lower ability of this species to maintain itself under shaded conditions. Relative growth rate (RGR in I. asarifolia was initially higher for high-light grown plants and after 20 days started decreasing, becoming similar to low-light plants at the last two harvests (at 30 and 40 days. In S. cayennensis, RGR was also higher for high-light plants; however, this trend was not significant at the first and last harvest dates (10 and 40 days. These results are discussed in relation to their ecological and weed management implications.Ipomoea asarifolia (Desr. Roem. & Schultz (Convolvulaceae e Stachytarpheta cayennensis (Rich Vahl. (Verbenaceae, duas plantas invasoras encontradas em pastagens e áreas agrícolas da Amazônia brasileira, foram cultivadas durante 40 dias, em câmaras de crescimento sob alto (800-1000 µmol m-² s-¹, "sol" e baixo (200-350 µmol m-² s-¹, "sombra" regime de luz. Em ambas as espécies a razão de massa e de área foliar por unidade de massa total da planta, e a área foliar por unidade de massa foliar foram maiores na sombra, enquanto a proporção de biomassa alocada para as raízes foi maior nas plantas ao sol. Em S. cayennensis a alocação de biomassa para tecido reprodutivo foi maior nas plantas ao sol, sugerindo uma provável menor habilidade dessa

  17. Residency Allocation Database

    Data.gov (United States)

    Department of Veterans Affairs — The Residency Allocation Database is used to determine allocation of funds for residency programs offered by Veterans Affairs Medical Centers (VAMCs). Information...

  18. What to Do with the Bounty? Organizational Patterns for the Implementation of Resources Allocated by the Courage to Change (Oz Letmura) Reform

    Science.gov (United States)

    Tamir, Emanuel; Shaked, Lea

    2016-01-01

    The research investigated the way in which school administrations implement resources provided by Israel's "Courage to Change" reform. The uniqueness of this reform stems from the fact that the allocated resources come in the form of "weekly instruction time" rather than finance, and the school management needs to decide how to…

  19. The flux-based PIN allocation mechanism can generate either canalyzed or diffuse distribution patterns depending on geometry and boundary conditions.

    Directory of Open Access Journals (Sweden)

    Michael Luke Walker

    Full Text Available Growth and morphogenesis in plants require controlled transport of the plant hormone auxin. An important participant is the auxin effluxing protein PIN, whose polarized subcellular localization allows it to effectively transport auxin large distances through tissues. The flux-based model, in which auxin flux through a wall stimulates PIN allocation to that wall, is a dominant contender among models determining where and in what quantity PIN is allocated to cell walls. In this paper we characterise the behaviour of flux-based PIN allocation models in various tissues of the shoot apical meristem. Arguing from both mathematical analysis and computer simulations, we describe the natural behaviours of this class of models under various circumstances. In particular, we demonstrate the important dichotomy between sink- and source- driven systems, and show that both diffuse and canalized PIN distributions can be generated simultaneously in the same tissue, without model hybridization or variation of PIN-related parameters. This work is performed in the context of the shoot apical and floral meristems and is applicable to the construction of a unified PIN allocation model.

  20. Soil respiration in Tibetan alpine grasslands: belowground biomass and soil moisture, but not soil temperature, best explain the large-scale patterns.

    Directory of Open Access Journals (Sweden)

    Yan Geng

    Full Text Available The Tibetan Plateau is an essential area to study the potential feedback effects of soils to climate change due to the rapid rise in its air temperature in the past several decades and the large amounts of soil organic carbon (SOC stocks, particularly in the permafrost. Yet it is one of the most under-investigated regions in soil respiration (Rs studies. Here, Rs rates were measured at 42 sites in alpine grasslands (including alpine steppes and meadows along a transect across the Tibetan Plateau during the peak growing season of 2006 and 2007 in order to test whether: (1 belowground biomass (BGB is most closely related to spatial variation in Rs due to high root biomass density, and (2 soil temperature significantly influences spatial pattern of Rs owing to metabolic limitation from the low temperature in cold, high-altitude ecosystems. The average daily mean Rs of the alpine grasslands at peak growing season was 3.92 µmol CO(2 m(-2 s(-1, ranging from 0.39 to 12.88 µmol CO(2 m(-2 s(-1, with average daily mean Rs of 2.01 and 5.49 µmol CO(2 m(-2 s(-1 for steppes and meadows, respectively. By regression tree analysis, BGB, aboveground biomass (AGB, SOC, soil moisture (SM, and vegetation type were selected out of 15 variables examined, as the factors influencing large-scale variation in Rs. With a structural equation modelling approach, we found only BGB and SM had direct effects on Rs, while other factors indirectly affecting Rs through BGB or SM. Most (80% of the variation in Rs could be attributed to the difference in BGB among sites. BGB and SM together accounted for the majority (82% of spatial patterns of Rs. Our results only support the first hypothesis, suggesting that models incorporating BGB and SM can improve Rs estimation at regional scale.

  1. Soil Respiration in Tibetan Alpine Grasslands: Belowground Biomass and Soil Moisture, but Not Soil Temperature, Best Explain the Large-Scale Patterns

    Science.gov (United States)

    Geng, Yan; Wang, Yonghui; Yang, Kuo; Wang, Shaopeng; Zeng, Hui; Baumann, Frank; Kuehn, Peter; Scholten, Thomas; He, Jin-Sheng

    2012-01-01

    The Tibetan Plateau is an essential area to study the potential feedback effects of soils to climate change due to the rapid rise in its air temperature in the past several decades and the large amounts of soil organic carbon (SOC) stocks, particularly in the permafrost. Yet it is one of the most under-investigated regions in soil respiration (Rs) studies. Here, Rs rates were measured at 42 sites in alpine grasslands (including alpine steppes and meadows) along a transect across the Tibetan Plateau during the peak growing season of 2006 and 2007 in order to test whether: (1) belowground biomass (BGB) is most closely related to spatial variation in Rs due to high root biomass density, and (2) soil temperature significantly influences spatial pattern of Rs owing to metabolic limitation from the low temperature in cold, high-altitude ecosystems. The average daily mean Rs of the alpine grasslands at peak growing season was 3.92 µmol CO2 m−2 s−1, ranging from 0.39 to 12.88 µmol CO2 m−2 s−1, with average daily mean Rs of 2.01 and 5.49 µmol CO2 m−2 s−1 for steppes and meadows, respectively. By regression tree analysis, BGB, aboveground biomass (AGB), SOC, soil moisture (SM), and vegetation type were selected out of 15 variables examined, as the factors influencing large-scale variation in Rs. With a structural equation modelling approach, we found only BGB and SM had direct effects on Rs, while other factors indirectly affecting Rs through BGB or SM. Most (80%) of the variation in Rs could be attributed to the difference in BGB among sites. BGB and SM together accounted for the majority (82%) of spatial patterns of Rs. Our results only support the first hypothesis, suggesting that models incorporating BGB and SM can improve Rs estimation at regional scale. PMID:22509373

  2. Soil respiration in Tibetan alpine grasslands: belowground biomass and soil moisture, but not soil temperature, best explain the large-scale patterns.

    Science.gov (United States)

    Geng, Yan; Wang, Yonghui; Yang, Kuo; Wang, Shaopeng; Zeng, Hui; Baumann, Frank; Kuehn, Peter; Scholten, Thomas; He, Jin-Sheng

    2012-01-01

    The Tibetan Plateau is an essential area to study the potential feedback effects of soils to climate change due to the rapid rise in its air temperature in the past several decades and the large amounts of soil organic carbon (SOC) stocks, particularly in the permafrost. Yet it is one of the most under-investigated regions in soil respiration (Rs) studies. Here, Rs rates were measured at 42 sites in alpine grasslands (including alpine steppes and meadows) along a transect across the Tibetan Plateau during the peak growing season of 2006 and 2007 in order to test whether: (1) belowground biomass (BGB) is most closely related to spatial variation in Rs due to high root biomass density, and (2) soil temperature significantly influences spatial pattern of Rs owing to metabolic limitation from the low temperature in cold, high-altitude ecosystems. The average daily mean Rs of the alpine grasslands at peak growing season was 3.92 µmol CO(2) m(-2) s(-1), ranging from 0.39 to 12.88 µmol CO(2) m(-2) s(-1), with average daily mean Rs of 2.01 and 5.49 µmol CO(2) m(-2) s(-1) for steppes and meadows, respectively. By regression tree analysis, BGB, aboveground biomass (AGB), SOC, soil moisture (SM), and vegetation type were selected out of 15 variables examined, as the factors influencing large-scale variation in Rs. With a structural equation modelling approach, we found only BGB and SM had direct effects on Rs, while other factors indirectly affecting Rs through BGB or SM. Most (80%) of the variation in Rs could be attributed to the difference in BGB among sites. BGB and SM together accounted for the majority (82%) of spatial patterns of Rs. Our results only support the first hypothesis, suggesting that models incorporating BGB and SM can improve Rs estimation at regional scale.

  3. Modelling C allocation in response to nutrient availability

    Science.gov (United States)

    Stocker, Benjamin; Prentice, Colin

    2015-04-01

    Carbon (C) allocation in ecosystems is a key variable of the global terrestrial C cycle. While photosynthesis governs the amount of C that enters ecosystems, its subsequent allocation to compartments with different life times determines its over-all residence time and variations in allocation patterns drive changes in ecosystem C balance and its response to environmental change. A better understanding of the controls on allocation is thus key to improving global vegetation models that commonly rely on using fixed partitioning factors. Observational data suggests variations of ecosystem structure and functioning along large-scale gradients of resource availability. Below-ground C allocation, inferred as gross primary production minus above-ground biomass production increases along gradients of decreasing nutrient availability. This is not only due to more root growth, but also due to enhanced production of exudates and stimulation of root symbionts and has been interpreted to reflect optimal plant allocation decisions under a varying soil fertility status. Here, we propose a model that accounts for trade-offs between (i) growth in above-ground and (ii) below-ground plant compartments, (iii) exudation to the rhizosphere and root symbionts and (iv) temporary storage in non-structural pools. By postulating the maximization of long-term growth under a given (seasonal regime) of soil nitrogen (N) availability, we attempt to reproduce observed large-scale gradients. The model is formulated based on a C cost for different N uptake decisions, where the cost is a function of N availability, root mass, and soil temperature (for biological N fixation). On a daily time scale, ecosystem N uptake may be realized by C exudation to the rhizosphere and/or symbiotic fixation of atmospheric N2. On an annual time scale, allocation to roots versus leaves is adjusted to soil inorganic N availability and modeled to yield maximum total growth. Exudation versus temporary storage of C is

  4. Allometric equations for estimating belowground biomass ofAndrostachys johnsoniiPrain.

    Science.gov (United States)

    Magalhães, Tarquinio Mateus

    2015-12-01

    The belowground component of the trees is still poorly known because it needs labour- and time-intensive in situ measurements. However, belowground biomass (BGB) constitutes a significant share of the total forest biomass. I analysed the BGB allocation patterns, fitted models for estimating root components and root system biomasses, and called attention for its possible use in predicting anchoring functions of the different root components. More than half and almost one third of BGB is allocated to the lateral roots and to the root collar, respectively. More than 80% of the BGB is found at a depth range of 9.6-61.2 cm. As the tree size increased, the proportion of BGB allocated to taproots decreased and that allocated to lateral roots increased. All independent models performed almost equally, with the predictors explaining, on average, 98% of the variation in the BGB. It was hypothesised that BGB allocation patterns are a response of the anchoring functions of the tap and lateral roots and therefore, root component biomass models can be used as a methodology to predict anchoring functions of the different root components. Based on the fact that all models performed almost equally, the models using either diameter at breast height (DBH) exclusively as a predictor should be preferred, as tree height is difficult to measure. Models using the root collar diameter (RCD) only should be preferred when the tree is found cut down, as sometimes the RCD is affected by root buttress. Given the large sample size, the validation results, and the coverage of a wide geographical, soil and climatic range, the models fitted can be applied in all A. johnsonii stands in Mozambique.

  5. Variation in stem mortality rates determines patterns of above-ground biomass in Amazonian forests: implications for dynamic global vegetation models.

    Science.gov (United States)

    Johnson, Michelle O; Galbraith, David; Gloor, Manuel; De Deurwaerder, Hannes; Guimberteau, Matthieu; Rammig, Anja; Thonicke, Kirsten; Verbeeck, Hans; von Randow, Celso; Monteagudo, Abel; Phillips, Oliver L; Brienen, Roel J W; Feldpausch, Ted R; Lopez Gonzalez, Gabriela; Fauset, Sophie; Quesada, Carlos A; Christoffersen, Bradley; Ciais, Philippe; Sampaio, Gilvan; Kruijt, Bart; Meir, Patrick; Moorcroft, Paul; Zhang, Ke; Alvarez-Davila, Esteban; Alves de Oliveira, Atila; Amaral, Ieda; Andrade, Ana; Aragao, Luiz E O C; Araujo-Murakami, Alejandro; Arets, Eric J M M; Arroyo, Luzmila; Aymard, Gerardo A; Baraloto, Christopher; Barroso, Jocely; Bonal, Damien; Boot, Rene; Camargo, Jose; Chave, Jerome; Cogollo, Alvaro; Cornejo Valverde, Fernando; Lola da Costa, Antonio C; Di Fiore, Anthony; Ferreira, Leandro; Higuchi, Niro; Honorio, Euridice N; Killeen, Tim J; Laurance, Susan G; Laurance, William F; Licona, Juan; Lovejoy, Thomas; Malhi, Yadvinder; Marimon, Bia; Marimon, Ben Hur; Matos, Darley C L; Mendoza, Casimiro; Neill, David A; Pardo, Guido; Peña-Claros, Marielos; Pitman, Nigel C A; Poorter, Lourens; Prieto, Adriana; Ramirez-Angulo, Hirma; Roopsind, Anand; Rudas, Agustin; Salomao, Rafael P; Silveira, Marcos; Stropp, Juliana; Ter Steege, Hans; Terborgh, John; Thomas, Raquel; Toledo, Marisol; Torres-Lezama, Armando; van der Heijden, Geertje M F; Vasquez, Rodolfo; Guimarães Vieira, Ima Cèlia; Vilanova, Emilio; Vos, Vincent A; Baker, Timothy R

    2016-12-01

    Understanding the processes that determine above-ground biomass (AGB) in Amazonian forests is important for predicting the sensitivity of these ecosystems to environmental change and for designing and evaluating dynamic global vegetation models (DGVMs). AGB is determined by inputs from woody productivity [woody net primary productivity (NPP)] and the rate at which carbon is lost through tree mortality. Here, we test whether two direct metrics of tree mortality (the absolute rate of woody biomass loss and the rate of stem mortality) and/or woody NPP, control variation in AGB among 167 plots in intact forest across Amazonia. We then compare these relationships and the observed variation in AGB and woody NPP with the predictions of four DGVMs. The observations show that stem mortality rates, rather than absolute rates of woody biomass loss, are the most important predictor of AGB, which is consistent with the importance of stand size structure for determining spatial variation in AGB. The relationship between stem mortality rates and AGB varies among different regions of Amazonia, indicating that variation in wood density and height/diameter relationships also influences AGB. In contrast to previous findings, we find that woody NPP is not correlated with stem mortality rates and is weakly positively correlated with AGB. Across the four models, basin-wide average AGB is similar to the mean of the observations. However, the models consistently overestimate woody NPP and poorly represent the spatial patterns of both AGB and woody NPP estimated using plot data. In marked contrast to the observations, DGVMs typically show strong positive relationships between woody NPP and AGB. Resolving these differences will require incorporating forest size structure, mechanistic models of stem mortality and variation in functional composition in DGVMs. © 2016 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

  6. Spatial patterns in abundance, taxonomic composition and carbon biomass of nano- and microphytoplankton in Subarctic and Arctic Seas

    Science.gov (United States)

    Crawford, David W.; Cefarelli, Adrián O.; Wrohan, Ian A.; Wyatt, Shea N.; Varela, Diana E.

    2018-03-01

    In the summers of 2007 and 2008, we studied assemblages of nano- and microphytoplankton from the subsurface chlorophyll maximum (SCM) across five broad oceanographic domains in the seas surrounding northern North America. These domains are the eastern Subarctic North Pacific (ESNP), Bering and Chukchi Seas (BE-CH), Beaufort Sea and Canada Basin (BS-CB), Canadian Arctic Archipelago (CAA), and Baffin Bay and Labrador Sea (BB-LS). Average abundance and total carbon biomass (C) of phytoplankton (>2 μm) varied ∼10-fold and ∼20-fold, respectively, across the five domains. In the BE-CH, CAA and BB-LS, diatoms averaged 35-70% and dinoflagellates 11-45% of total phytoplankton C (>2 μm), whereas in the ESNP and BS-CB, unidentified flagellates/coccoids (2-8 μm) represented a greater proportion of total C (27% and 39% respectively) than in the other domains. In the BE-CH and BB-LS, phytoplankton C (>2 μm) was dominated by dinoflagellates of the genus Gymnodinium, centric diatoms including Thalassiosira spp. and Chaetoceros spp., unidentified flagellates/coccoids (2-8 μm), and cryptomonads. In contrast, diatoms such as Thalassiosira spp. and its resting spores dominated C in the CAA, with dinoflagellates being less significant than in the BE-CH and BB-LS. Unidentified flagellates/coccoids (2-8 μm), Gymnodinium spp., and cryptomonads dominated in the ESNP, and particularly in the BS-CB, where diatoms contributed only 18% of the very low levels of total phytoplankton C (>2 μm). Phytoplankton C (>2 μm) to chlorophyll a ratios (phyto C:chl a) averaged only 31 g C g chl a-1 in the oligotrophic BS-CB domain, and 51-150 g C g chl a-1 in the other domains, whereas ratios of biogenic silica to phytoplankton C (>2 μm) (bSi:phyto C) were lowest in the eastern domains. Estimates of phytoplankton C were highly sensitive to the choice of C to cell volume equations (C:vol) adopted in the calculations, particularly in diatom-rich areas. This study highlights how diatoms and

  7. Phosphate supply explains variation in nucleic acid allocation but not C : P stoichiometry in the western North Atlantic

    Science.gov (United States)

    Zimmerman, A. E.; Martiny, A. C.; Lomas, M. W.; Allison, S. D.

    2014-03-01

    Marine microbial communities mediate many biogeochemical transformations in the ocean. Consequently, processes such as primary production and carbon (C) export are linked to nutrient regeneration and are influenced by the resource demand and elemental composition of marine microbial biomass. Laboratory studies have demonstrated that differential partitioning of element resources to various cellular components can directly influence overall cellular elemental ratios, especially with respect to growth machinery (i.e., ribosomal RNA) and phosphorus (P) allocation. To investigate whether allocation to RNA is related to biomass P content and overall C : P biomass composition in the open ocean, we characterized patterns of P allocation and C : P elemental ratios along an environmental gradient of phosphate supply in the North Atlantic subtropical gyre (NASG) from 35.67° N, 64.17° W to 22.676° N, 65.526° W. Because the NASG is characterized as a P-stressed ecosystem, we hypothesized that biochemical allocation would reflect sensitivity to bioavailable phosphate, such that greater phosphate supply would result in increased allocation toward P-rich RNA for growth. We predicted these changes in allocation would also result in lower C : P ratios with increased phosphate supply. However, bulk C : P ratios were decoupled from allocation to nucleic acids and did not appear to vary systematically across a phosphate supply gradient of 2.2-14.7 μmol m-2 d-1. Overall, we found that C : P ratios ranged from 188 to 306 along the transect, and RNA represented only 6-12% of total particulate P, whereas DNA represented 11-19%. We did find that allocation to RNA was positively correlated with phosphate supply rate, suggesting a consistent physiological response in biochemical allocation to resource supply within the whole community. These results suggest that community composition and/or nonnucleic acid P pools may influence ecosystem-scale variation in C : P stoichiometry more than

  8. Carbon-nitrogen interactions and biomass partitioning of Carex rostrata grown at three levels of nitrogen supply

    Energy Technology Data Exchange (ETDEWEB)

    Saarinen, T. [Helsinki Univ. (Finland). Dept. of Ecology and Systematics

    1996-12-31

    Biomass and production of vascular plants constitutes a major source of carbon input in peatlands. As rates of decomposition vary considerably with depth, the vertical distribution of biomass may substantially affect accumulation of carbon in peatlands. Therefore, allocation patterns between shoot and roots are particularly important when considering carbon balance of peatland ecosystems. The stimulatory effect of increasing atmospheric concentration of CO{sub 2} or photosynthesis may increase availability of carbon to most C3 plants. Availability of nitrogen may also alter both due to increased atmospheric deposition and changer in mineralisation rates associated with climate change. Most root-shoot partitioning models predict that allocation of biomass is dependent of the availability and uptake of carbon and nitrogen. A decrease in supply of carbon would favour allocation to shoots and a decrease in supply of nitrogen would increase allocation to roots. At a cellular level, non structural carbohydrates and free amino acids are thought to represent the biochemically available fraction of carbon and nitrogen, respectively. The aim of this work is study the long-term growth responses of Carex rostrata to changes in the availability of nitrogen. Special attention is paid to soluble sugars ant free amino acids, which may control partitioning of biomass. (10 refs.)

  9. Economics of multifunctional biomass systems

    International Nuclear Information System (INIS)

    Ignaciuk, A.

    2006-01-01

    Chapter 2 focuses on the competition between traditional agricultural production and growing demand for biomass plantations. The aim of this chapter is to investigate the effects of various energy policies, aimed at both reducing the emissions of greenhouse gases (GHG) and increasing the share of bioelectricity, on the production of biomass and agricultural commodities. A partial equilibrium model is developed to illustrate some of the potential impacts of these policies on greenhouse gas emissions, land reallocation and prices of food and electricity. A partial framework is used, because it provides a transparent and consistent structure and enables to concentrate on only the relevant economic sectors (agriculture, biomass, conventional electricity, and bioelectricity). In the model, GHG emissions depend on land use patterns and fossil fuel use. The innovative element of this model is that it integrates two distinct analyses, namely an analysis of substitution mechanisms between energy from biomass and from fossil fuels, and an analysis of the effects of changes in demand for biomass on land use and GHG emissions. Chapter 3 deals with the impact of climate policies on land use and land cover change and possible impacts on reestablishment of semi-natural areas, mainly forestry and willow plantations. The aim of this chapter is to investigate the impact of climate policies to reduce greenhouse gas emissions by means of promoting biomass and bioelectricity. In this context, the analysis is performed on how these policies might affect production of agricultural commodities and trade patterns of biomass and bioelectricity. To this purpose, an applied general equilibrium model (AGE) is developed with special attention to biomass and agricultural crops for a small open economy, with an Armington specification for international trade. Chapter 4 focuses on the multiproductivity issues of agriculture, biomass, and forestry sectors resulting in additional production inputs

  10. Biomass pretreatment

    Science.gov (United States)

    Hennessey, Susan Marie; Friend, Julie; Elander, Richard T; Tucker, III, Melvin P

    2013-05-21

    A method is provided for producing an improved pretreated biomass product for use in saccharification followed by fermentation to produce a target chemical that includes removal of saccharification and or fermentation inhibitors from the pretreated biomass product. Specifically, the pretreated biomass product derived from using the present method has fewer inhibitors of saccharification and/or fermentation without a loss in sugar content.

  11. Influence of landscape heterogeneity on spatial patterns of wood productivity, wood specific density and above ground biomass in Amazonia

    Directory of Open Access Journals (Sweden)

    L. O. Anderson

    2009-09-01

    Full Text Available Long-term studies using the RAINFOR network of forest plots have generated significant insights into the spatial and temporal dynamics of forest carbon cycling in Amazonia. In this work, we map and explore the landscape context of several major RAINFOR plot clusters using Landsat ETM+ satellite data. In particular, we explore how representative the plots are of their landscape context, and test whether bias in plot location within landscapes may be influencing the regional mean values obtained for important forest biophysical parameters. Specifically, we evaluate whether the regional variations in wood productivity, wood specific density and above ground biomass derived from the RAINFOR network could be driven by systematic and unintentional biases in plot location. Remote sensing data covering 45 field plots were aggregated to generate landscape maps to identify the specific physiognomy of the plots. In the Landsat ETM+ data, it was possible to spectrally differentiate three types of terra firme forest, three types of forests over Paleovarzea geomorphologycal formation, two types of bamboo-dominated forest, palm forest, Heliconia monodominant vegetation, swamp forest, disturbed forests and land use areas. Overall, the plots were generally representative of the forest physiognomies in the landscape in which they are located. Furthermore, the analysis supports the observed regional trends in those important forest parameters. This study demonstrates the utility of landscape scale analysis of forest physiognomies for validating and supporting the finds of plot based studies. Moreover, the more precise geolocation of many key RAINFOR plot clusters achieved during this research provides important contextual information for studies employing the RAINFOR database.

  12. Estimating Swedish biomass energy supply

    International Nuclear Information System (INIS)

    Johansson, J.; Lundqvist, U.

    1999-01-01

    Biomass is suggested to supply an increasing amount of energy in Sweden. There have been several studies estimating the potential supply of biomass energy, including that of the Swedish Energy Commission in 1995. The Energy Commission based its estimates of biomass supply on five other analyses which presented a wide variation in estimated future supply, in large part due to differing assumptions regarding important factors. In this paper, these studies are assessed, and the estimated potential biomass energy supplies are discusses regarding prices, technical progress and energy policy. The supply of logging residues depends on the demand for wood products and is limited by ecological, technological, and economic restrictions. The supply of stemwood from early thinning for energy and of straw from cereal and oil seed production is mainly dependent upon economic considerations. One major factor for the supply of willow and reed canary grass is the size of arable land projected to be not needed for food and fodder production. Future supply of biomass energy depends on energy prices and technical progress, both of which are driven by energy policy priorities. Biomass energy has to compete with other energy sources as well as with alternative uses of biomass such as forest products and food production. Technical progress may decrease the costs of biomass energy and thus increase the competitiveness. Economic instruments, including carbon taxes and subsidies, and allocation of research and development resources, are driven by energy policy goals and can change the competitiveness of biomass energy

  13. Standing crop and aboveground biomass partitioning of a dwarf mangrove forest in Taylor River Slough, Florida

    Science.gov (United States)

    Coronado-Molina, C.; Day, J.W.; Reyes, E.; Perez, B.C.

    2004-01-01

    The structure and standing crop biomass of a dwarf mangrove forest, located in the salinity transition zone ofTaylor River Slough in the Everglades National Park, were studied. Although the four mangrove species reported for Florida occurred at the study site, dwarf Rhizophora mangle trees dominated the forest. The structural characteristics of the mangrove forest were relatively simple: tree height varied from 0.9 to 1.2 meters, and tree density ranged from 7062 to 23 778 stems haa??1. An allometric relationship was developed to estimate leaf, branch, prop root, and total aboveground biomass of dwarf Rhizophora mangle trees. Total aboveground biomass and their components were best estimated as a power function of the crown area times number of prop roots as an independent variable (Y = B ?? Xa??0.5083). The allometric equation for each tree component was highly significant (pRhizophora mangle contributed 85% of total standing crop biomass. Conocarpus erectus, Laguncularia racemosa, and Avicennia germinans contributed the remaining biomass. Average aboveground biomass allocation was 69% for prop roots, 25% for stem and branches, and 6% for leaves. This aboveground biomass partitioning pattern, which gives a major role to prop roots that have the potential to produce an extensive root system, may be an important biological strategy in response to low phosphorus availability and relatively reduced soils that characterize mangrove forests in South Florida.

  14. Dominance patterns in macroalgal and phytoplankton biomass under different nutrient loads in subtropical coastal lagoons of the SE Gulf of California

    International Nuclear Information System (INIS)

    Páez-Osuna, F.; Piñón-Gimate, A.; Ochoa-Izaguirre, M.J.

    2013-01-01

    Highlights: • Nine macroalgal blooms were examined in five lagoons from SE Gulf of California. • Shrimp farms were the main point source of nutrients loads to the lagoons. • Biomass as phytoplankton ranged 40–792 mg m −2 and macroalgal of 1–296 g m −2 . • Biomass (phytoplankton + macroalgae) was the same tendency that nutrient loads. • Phytoplankton and macroalgal biomass were a significant correlation with N:P ratio. -- Abstract: Nine macroalgal blooms were studied in five coastal lagoons of the SE Gulf of California. The nutrient loads from point and diffuse sources were estimated in the proximity of the macroalgal blooms. Chlorophyll a and macroalgal biomass were measured during the dry, rainy and cold seasons. Shrimp farms were the main point source of nitrogen and phosphorus loads for the lagoons. High biomasses were found during the dry season for phytoplankton at site 6 (791.7 ± 34.6 mg m −2 ) and during the rainy season for macroalgae at site 4 (296.0 ± 82.4 g m −2 ). Depending on the season, the phytoplankton biomass ranged between 40.0 and 791.7 mg m −2 and the macroalgal biomass between 1 and 296.0 g m −2 . The bulk biomass (phytoplankton + macroalgal) displayed the same tendency as the nutrient loads entering the coastal lagoons. Phytoplankton and macroalgal biomass presented a significant correlation with the atomic N:P ratio

  15. New insights into carbon allocation by trees from the hypothesis that annual wood production is maximized.

    Science.gov (United States)

    McMurtrie, Ross E; Dewar, Roderick C

    2013-09-01

    Allocation of carbon (C) between tree components (leaves, fine roots and woody structures) is an important determinant of terrestrial C sequestration. Yet, because the mechanisms underlying C allocation are poorly understood, it is a weak link in current earth-system models. We obtain new theoretical insights into C allocation from the hypothesis (MaxW) that annual wood production is maximized. MaxW is implemented using a model of tree C and nitrogen (N) balance with a vertically resolved canopy and root system for stands of Norway spruce (Picea abies). MaxW predicts optimal vertical profiles of leaf N and root biomass, optimal canopy leaf area index and rooting depth, and the associated optimal pattern of C allocation. Key insights include a predicted optimal C-N functional balance between leaves at the base of the canopy and the deepest roots, according to which the net C export from basal leaves is just sufficient to grow the basal roots required to meet their N requirement. MaxW links the traits of basal leaves and roots to whole-tree C and N uptake, and unifies two previous optimization hypotheses (maximum gross primary production, maximum N uptake) that have been applied independently to canopies and root systems. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  16. Functioning of Plantago major and Urtica dioica exposed to elevated CO{sub 2}. Analysis of growth pattern in relation to C and N allocation

    Energy Technology Data Exchange (ETDEWEB)

    Den Hertog, J.

    1997-12-31

    The first part of this thesis deals with the growth response of P. major and U. dioica to a doubling of the ambient CO2 concentration grown with free access to nutrients (chapters 2 and 3). The questions, how relative growth rate (RGR) and other growth variables of wild plants are affected by elevated CO2 and what time course CO2 effects on the various growth variables have, are dealt with in chapter 2 for P. major. This analysis is extended to the relationship between the C and N metabolism in P. major and U. dioica, as affected by the CO2 concentration, in chapter 3. Chapter 4 focuses on the response of P. major to a combination of elevated CO2 and a growth-limiting dose of N. The analysis includes all factors needed to calculate a carbon balance, as well as data on nonstructural carbohydrates and total nitrogen concentrations. The use of fixed exponential addition rates for the supply of nitrate allows to establish relationships between growth variables and total plant nitrogen concentration (N), without interference of differences in plant size, such as often occurs in studies on growth under nutrient-limited conditions. The data from chapter 4 are used in a model study to evaluate the impact of the mode of nutrient limitation, as used in many studies, on the effect of elevated CO2, in combination with nutrient limitation, on plant growth. This chapter elucidates pitfalls in the experimental setup that are often overlooked and indicates possible causes for discrepancies between various studies concerned with the allocation of dry matter in relation to the CO2 treatment. The effect of an increase of the atmospheric CO2 concentration on the rate of respiration has caused controversy over the last ten years. Data on root respiration are presented in chapter 6. The data are related to possible effects of elevated CO, on the degree of stimulation of the RGR and on the concentration of nonstructural carbohydrates. A possible role for CO2 effects on cytochrome and

  17. Dynamic Channel Allocation

    Science.gov (United States)

    2003-09-01

    21 9. Beowulf Ethernet Channel Bonding.................................................22 F. SUMMARY...on demand, hybrid channel allocation in wireless networks, and 3 Beowulf Ethernet channel bonding. The background information presented in this...channels are available for dynamic allocation [Ref 32]. 9. Beowulf Ethernet Channel Bonding A by-product of using older computers in a NASA research lab

  18. Exposure to maternal diabetes is associated with altered fetal growth patterns: A hypothesis regarding metabolic allocation to growth under hyperglycemic-hypoxemic conditions.

    Science.gov (United States)

    Lampl, Michelle; Jeanty, Philippe

    2004-01-01

    The prevalence of diabetes is rising worldwide, including women who grew poorly in early life, presenting intergenerational health problems for their offspring. It is well documented that fetuses exposed to maternal diabetes during pregnancy experience both macrosomia and poor growth outcomes in birth size. Less is known about the in utero growth patterns that precede these risk factor expressions. Fetal growth patterns and the effects of clinical class and glycemic control were investigated in 37 diabetic pregnant women and their fetuses and compared to 29 nondiabetic, nonsmoking maternal/fetal pairs who were participants in a biweekly longitudinal ultrasound study with measurements of the head, limb, and trunk dimensions. White clinical class of the diabetic women was recorded (A2-FR) and glycosylated hemoglobin levels taken at the time of measurement assessed glycemic control (median 6.9%, interquartile range 5.6-9.2%). No significant difference in fetal weight was found by exposure. The exposed sample had greater abdominal circumferences from 21 weeks (P fetuses had a smaller slope for the occipital frontal diameter (P = 0.00) and were brachycephalic. They experienced a proximal/distal growth gradient in limb proportionality with higher humerus / femur ratios (P = 0.04) and arms relatively long by comparison with legs (P = 0.02). HbA1c levels above 7.5% accompanied shorter femur length for thigh circumference after 30 gestational weeks of age. Significant effects of diabetic clinical class and glycemic control were identified in growth rate timing. These growth patterns suggest that hypoxemic and hyperglycemic signals cross-talk with their target receptors in a developmentally regulated, hierarchical sequence. The increase in fetal fat often documented with diabetic pregnancy may reflect altered growth at the level of cell differentiation and proximate mechanisms controlling body composition. These data suggest that the maternal-fetal interchange circuit

  19. A decade of free‐air CO2 enrichment increased the carbon throughput in a grass‐clover ecosystem but did not drastically change carbon allocation patterns

    DEFF Research Database (Denmark)

    Staddon, Philip Louis; Reinsch, Sabine; Olsson, Pål A.

    2014-01-01

    The response of the soil carbon cycle to increasing atmospheric CO2 concentration has far reaching consequences for the ecosystem carbon balance under future climatic conditions. We report on work carried out in the Swiss free‐air CO2 enrichment (FACE) experiment, where we used in situ 13CO2...... labelling to determine whether elevated CO2 (+230 μL L−1) concentration changes the fate of recently assimilated carbon in the soil microbial community. Elevated CO2 (eCO2) concentration had an overall positive effect on microbial abundance (P ... increased quantities. Gram‐negative bacteria and saprotrophic fungi tended to utilize a higher amount of recently assimilated carbon under eCO2. Arbuscular mycorrhizal fungi (AMF) utilized plant‐assimilated carbon within 1 day after the 13CO2 pulse and 13C uptake patterns in AMF suggest that carbon transfer...

  20. Biomass Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Decker, Steve [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Brunecky, Roman [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lin, Chien-Yuan [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Amore, Antonella [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wei, Hui [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Chen, Xiaowen [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tucker, Melvin P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Czernik, Stefan [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sluiter, Amie D [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhang, Min [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Magrini, Kimberly A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Himmel, Michael E [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sheehan, John [Formerly NREL; Dayton, David C. [Formerly NREL; Bozell, Joseph J. [Formerly NREL; Adney, William S. [Formerly NREL; Aden, Andy [Formerly NREL; Hames, Bonnie [Formerly NREL; Thomas, Steven R. [Formerly NREL; Bain, Richard L. [Formerly NREL

    2017-08-02

    Biomass constitutes all the plant matter found on our planet, and is produced directly by photosynthesis, the fundamental engine of life on earth. It is the photosynthetic capability of plants to utilize carbon dioxide from the atmosphere that leads to its designation as a 'carbon neutral' fuel, meaning that it does not introduce new carbon into the atmosphere. This article discusses the life cycle assessments of biomass use and the magnitude of energy captured by photosynthesis in the form of biomass on the planet to appraise approaches to tap this energy to meet the ever-growing demand for energy.

  1. Biomass energy

    International Nuclear Information System (INIS)

    Pasztor, J.; Kristoferson, L.

    1992-01-01

    Bioenergy systems can provide an energy supply that is environmentally sound and sustainable, although, like all energy systems, they have an environmental impact. The impact often depends more on the way the whole system is managed than on the fuel or on the conversion technology. The authors first describe traditional biomass systems: combustion and deforestation; health impact; charcoal conversion; and agricultural residues. A discussion of modern biomass systems follows: biogas; producer gas; alcohol fuels; modern wood fuel resources; and modern biomass combustion. The issue of bioenergy and the environment (land use; air pollution; water; socioeconomic impacts) and a discussion of sustainable bioenergy use complete the paper. 53 refs., 9 figs., 14 tabs

  2. Developing equations for estimating tree component biomass for naturally regenerated shorteaf pine in southeast Oklahoma with application to biomass partitioning in thinned and unthinned stands

    Science.gov (United States)

    Nabin Gyawali; Thomas B. Lynch; Rodney E. Will

    2013-01-01

    Traditionally, the main focus of forest production has usually been to maximize allocation of biomass to merchantable stem wood. But the assessment of biomass partitioning in stands is needed to address management concerns such as stem production and allocation, carbon sequestration, wildland fire, whole tree harvesting, etc. Thinning mainly increases the bole diameter...

  3. CPD Allocations and Awards

    Data.gov (United States)

    Department of Housing and Urban Development — The CPD Allocation and Award database provides filterable on-screen and exportable reports on select programs, such as the Community Development Block Grant Program,...

  4. Biomass [updated

    Energy Technology Data Exchange (ETDEWEB)

    Turhollow Jr, Anthony F [ORNL

    2016-01-01

    Biomass resources and conversion technologies are diverse. Substantial biomass resources exist including woody crops, herbaceous perennials and annuals, forest resources, agricultural residues, and algae. Conversion processes available include fermentation, gasification, pyrolysis, anaerobic digestion, combustion, and transesterification. Bioderived products include liquid fuels (e.g. ethanol, biodiesel, and gasoline and diesel substitutes), gases, electricity, biochemical, and wood pellets. At present the major sources of biomass-derived liquid fuels are from first generation biofuels; ethanol from maize and sugar cane (89 billion L in 2013) and biodiesel from vegetable oils and fats (24 billion liters in 2011). For other than traditional uses, policy in the forms of mandates, targets, subsidies, and greenhouse gas emission targets has largely been driving biomass utilization. Second generation biofuels have been slow to take off.

  5. Biomass recalcitrance

    DEFF Research Database (Denmark)

    Felby, Claus

    2009-01-01

    Alternative and renewable fuels derived from lignocellulosic biomass offer a promising alternative to conventional energy sources, and provide energy security, economic growth, and environmental benefits. However, plant cell walls naturally resist decomposition from microbes and enzymes - this co...

  6. PHOTOSYNTHESIS AND RESOURCE ALLOCATION OF THREE MOJAVE DESERT GRASSES IN RESPONSE TO ELEVATED ATMOSPHERIC CO2

    Energy Technology Data Exchange (ETDEWEB)

    L. A. DEFALCO; C. K. IVANS; P. VIVIN; J. R. SEEMANN; R. S. NOWAK

    2004-01-01

    Gas exchange, biomass and N allocation were compared among three Mojave Desert grasses representing different functional types to determine if photosynthetic responses and the associated allocation of resources within the plant changed after prolonged exposure to elevated CO{sub 2}. Leaf gas exchange characteristics were measured for Bromus madritensis ssp. rubens (C{sub 3} invasive annual), Achnatherum hymenoides (C{sub 3} native perennial) and Pleuraphis rigida (C{sub 4} native perennial) exposed to 360 {micro}mol mol{sup -1} (ambient) and 1000 {micro}mol mol{sup -1} (elevated) CO{sub 2} concentrations in a glasshouse experiment, and tissue biomass and total N pools were quantified from three harvests during development. The maximum rate of carboxylation by the N-rich enzyme Rubisco (Vc{sub max}), which was inferred from the relationship between net CO{sub 2} assimilation (A{sub net}) and intracellular CO{sub 2} concentration (c{sub i}), declined in the C{sub 3} species Bromus and Achnatherum across all sampling dates, but did not change at elevated CO{sub 2} for the C{sub 4} Pleuraphis. Whole plant N remained the same between CO{sub 2} treatments for all species, but patterns of allocation differed for the short- and long-lived C{sub 3} species. For Bromus, leaf N used for photosynthesis was reallocated to reproduction at elevated CO{sub 2} as inferred from the combination of lower Vc{sub max} and N per leaf area (NLA) at elevated CO{sub 2}, but similar specific leaf area (SLA, cm{sup 2} g{sup -1}), and of greater reproductive effort (RE) for the elevated CO{sub 2} treatment. Vc{sub max}, leaf N concentration and NLA declined for the perennial Achnatherum at elevated CO{sub 2} potentially due to accumulation of carbohydrates or changes in leaf morphology inferred from lower SLA and greater total biomass at elevated CO{sub 2}. In contrast, Vc{sub max} for the C{sub 4} perennial Pleuraphis did not change at elevated CO{sub 2}, and tissue biomass and total N were

  7. Dominance patterns in macroalgal and phytoplankton biomass under different nutrient loads in subtropical coastal lagoons of the SE Gulf of California.

    Science.gov (United States)

    Páez-Osuna, F; Piñón-Gimate, A; Ochoa-Izaguirre, M J; Ruiz-Fernández, A C; Ramírez-Reséndiz, G; Alonso-Rodríguez, R

    2013-12-15

    Nine macroalgal blooms were studied in five coastal lagoons of the SE Gulf of California. The nutrient loads from point and diffuse sources were estimated in the proximity of the macroalgal blooms. Chlorophyll a and macroalgal biomass were measured during the dry, rainy and cold seasons. Shrimp farms were the main point source of nitrogen and phosphorus loads for the lagoons. High biomasses were found during the dry season for phytoplankton at site 6 (791.7±34.6 mg m(-2)) and during the rainy season for macroalgae at site 4 (296.0±82.4 g m(-2)). Depending on the season, the phytoplankton biomass ranged between 40.0 and 791.7 mg m(-2) and the macroalgal biomass between 1 and 296.0 g m(-2). The bulk biomass (phytoplankton+macroalgal) displayed the same tendency as the nutrient loads entering the coastal lagoons. Phytoplankton and macroalgal biomass presented a significant correlation with the atomic N:P ratio. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Relationships between tree size, crown shape, gender segregation and sex allocation in Pinus halepensis, a Mediterranean pine tree.

    Science.gov (United States)

    Ne'eman, Gidi; Goubitz, Shirrinka; Werger, Marinus J A; Shmida, Avi

    2011-07-01

    Sex allocation has been studied mainly in small herbaceous plants but much less in monoecious wind-pollinated trees. The aim of this study was to explore changes in gender segregation and sex allocation by Pinus halepensis, a Mediterranean lowland pine tree, within tree crowns and between trees differing in their size or crown shape. The production of new male and female cones and sex allocation of biomass, nitrogen and phosphorus were studied. The relationship between branch location, its reproductive status and proxies of branch vigour was also studied. Small trees produced only female cones, but, as trees grew, they produced both male and female cones. Female cones were produced mainly in the upper part of the crown, and male cones in its middle and lower parts. Lateral branch density was correlated with the number of male but not female cones; lateral branches were more dense in large than in small trees and even denser in hemispherical trees. Apical branches grew faster, were thicker and their phosphorus concentration was higher than in lateral shoots. Nitrogen concentration was higher in cone-bearing apical branches than in apical vegetative branches and in lateral branches with or without cones. Allocation to male relative to female function increased with tree size as predicted by sex allocation theory. The adaptive values of sex allocation and gender segregation patterns in P. halepensis, in relation to its unique life history, are demonstrated and discussed. Small trees produce only female cones that have a higher probability of being pollinated than the probability of male cones pollinating; the female-first strategy enhances population spread. Hemispherical old trees are loaded with serotinous cones that supply enough seeds for post-fire germination; thus, allocation to males is more beneficial than to females.

  9. Risk capital allocation

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Smilgins, Aleksandrs

    Risk capital allocation problems have been widely discussed in the academic literature. We consider a company with multiple subunits having individual portfolios. Hence, when portfolios of subunits are merged, a diversification benefit arises: the risk of the company as a whole is smaller than th...... of new axioms related directly to the problem of risk capital allocation and show that the Lorenz set satisfies these new axioms in contrast to other well-known coherent methods. Finally, we discuss how to deal with non-uniqueness of the Lorenz set.......Risk capital allocation problems have been widely discussed in the academic literature. We consider a company with multiple subunits having individual portfolios. Hence, when portfolios of subunits are merged, a diversification benefit arises: the risk of the company as a whole is smaller than...... the sum of the risks of the individual sub-units. The question is how to allocate the risk capital of the company among the subunits in a fair way. In this paper we propose to use the Lorenz set as an allocation method. We show that the Lorenz set is operational and coherent. Moreover, we propose a set...

  10. Biomass partitioning and root morphology of savanna trees across a water gradient

    NARCIS (Netherlands)

    Tomlinson, K.W.; Sterck, F.J.; Bongers, F.; Silva, da D.A.; Barbosa, E.R.; Ward, D.; Bakker, F.T.; Kaauwen, van M.P.W.; Prins, H.H.T.; Bie, de S.; Langevelde, van F.

    2012-01-01

    1. Plant organ biomass partitioning has been hypothesized to be driven by resources, such that species from drier environments allocate more biomass to roots than species from wetter environments to access water at greater soil depths. In savanna systems, fire may select for greater allocation to

  11. Chronic nitrogen deposition alters tree allometric relationships: implications for biomass production and carbon storage.

    Science.gov (United States)

    Ibáñez, Inés; Zak, Donald R; Burton, Andrew J; Pregitzer, Kurt S

    2016-04-01

    As increasing levels of nitrogen (N) deposition impact many terrestrial ecosystems, understanding the potential effects of higher N availability is critical for forecasting tree carbon allocation patterns and thus future forest productivity. Most regional estimates of forest biomass apply allometric equations, with parameters estimated from a limited number of studies, to forest inventory data (i.e., tree diameter). However most of these allometric equations cannot account for potential effects of increased N availability on biomass allocation patterns. Using 18 yr of tree diameter, height, and mortality data collected for a dominant tree species (Acer saccharum) in an atmospheric N deposition experiment, we evaluated how greater N availability affects allometric relationships in this species. After taking into account site and individual variability, our results reveal significant differences in allometric parameters between ambient and experimental N deposition treatments. Large trees under experimental N deposition reached greater heights at a given diameter; moreover, their estimated maximum height (mean ± standard deviation: 33.7 ± 0.38 m) was significantly higher than that estimated under the ambient condition (31.3 ± 0.31 m). Within small tree sizes (5-10 cm diameter) there was greater mortality under experimental N deposition, whereas the relative growth rates of small trees were greater under experimental N deposition. Calculations of stemwood biomass using our parameter estimates for the diameter-height relationship indicated the potential for significant biases in these estimates (~2.5%), with under predictions of stemwood biomass averaging 4 Mg/ha lower if ambient parameters were to be used to estimate stem biomass of trees in the experimental N deposition treatment. As atmospheric N deposition continues to increase into the future, ignoring changes in tree allometry will contribute to the uncertainty associated with aboveground carbon storage

  12. Biomass potential

    Energy Technology Data Exchange (ETDEWEB)

    Asplund, D. [VTT Energy, Espoo (Finland)

    1996-12-31

    Biomass resources of the industrialised countries are enormous, if only a small fraction of set-aside fields were used for energy crops. Forest resources could also be utilised more efficiently than at present for large-scale energy production. The energy content of the annual net growth of the total wood biomass is estimated to be 180 million toe in Europe without the former USSR, and about 50 million toe of that in the EC area, in 1990. Presently, the harvesting methods of forest biomass for energy production are not yet generally competitive. Among the most promising methods are integrated harvesting methods, which supply both raw material to the industry and wood fuel for energy production. Several new methods for separate harvesting of energy wood are being developed in many countries. (orig.)

  13. Biomass IGCC

    Energy Technology Data Exchange (ETDEWEB)

    Salo, K.; Keraenen, H. [Enviropower Inc., Espoo (Finland)

    1996-12-31

    Enviropower Inc. is developing a modern power plant concept based on pressurised fluidized-bed gasification and gas turbine combined cycle (IGCC). The process is capable of maximising the electricity production with a variety of solid fuels - different biomass and coal types - mixed or separately. The development work is conducted on many levels. These and demonstration efforts are highlighted in this article. The feasibility of a pressurised gasification based processes compared to competing technologies in different applications is discussed. The potential of power production from biomass is also reviewed. (orig.) 4 refs.

  14. Biomass energy resource enhancement

    International Nuclear Information System (INIS)

    Grover, P.D.

    1995-01-01

    The demand for energy in developing countries is expected to increase to at least three times its present level within the next 25 years. If this demand is to be met by fossil fuels, an additional 2 billion tonnes of crude oil or 3 billion tonnes of coal would be needed every year. This consumption pattern, if allowed to proceed, would add 10 billion tonnes of CO 2 , to the global atmosphere each year, with its attendant risk of global warming. Therefore, just for our survival, it is imperative to progressively replace fossil fuels by biomass energy resources and to enhance the efficiency of use of the latter. Biomass is not only environmentally benign but is also abundant. It is being photosynthesised at the rate of 200 billion tonnes of carbon every year, which is equivalent to 10 times the world's present demand for energy. Presently, biomass energy resources are highly under-utilised in developing countries; when they are used it is through combustion, which is inefficient and causes widespread environmental pollution with its associated health hazards. Owing to the low bulk density and high moisture content of biomass, which make it difficult to collect, transport and store, as well as its ash-related thermochemical properties, its biodegradability and seasonal availability, the industrial use of biomass is limited to small and (some) medium-scale industries, most of which are unable to afford efficient but often costly energy conversion systems. Considering these constraints and the need to enhance the use base, biomass energy technologies appropriate to developing countries have been identified. Technologies such as briquetting and densification to upgrade biomass fuels are being adopted as conventional measures in some developing countries. The biomass energy base can be enhanced only once these technologies have been shown to be viable under local conditions and with local raw materials, after which they will multiply on their own, as has been the case

  15. Winter wheat optimizes allocation in response to carbon limitation

    Science.gov (United States)

    Huang, Jianbei; Hammerbacher, Almuth; Trumbore, Susan; Hartmann, Henrik

    2016-04-01

    • Plant photosynthesis is not carbon-saturated at current atmospheric CO2 concentration ([CO2]) thus carbon allocation priority is of critical importance in determining plant response to environmental changes, including increasing [CO2]. • We quantified the percentage of daytime net assimilation (A) allocated to whole-plant nighttime respiration (R) and structural growth (SG), nonstructural carbohydrates (NSC) and secondary metabolites (SMs) during winter wheat (Triticum aestivum) vegetative growth (over 4 weeks) at glacial, ambient, and elevated [CO2] (170, 390 and 680 ppm). • We found that R/A remained relatively constant (11-14%) across [CO2] treatments, whereas plants allocated less C to growth and more C to export at low [CO2] than elevated [CO2]; low [CO2] grown plants tended to invest overall less C into NSC and SMs than to SG due to reduced NSC availability; while leaf SMs/NSC was greater at 170 ppm than at 680 ppm [CO2] this was the opposite for root SMs/NSC; biomass, especially NSC, were preferentially allocated to leaves instead of stems and roots, likely to relieve C limitation induced by low [CO2]. • We conclude that C limitation may force plants to reduce C allocation to long-term survival in order to secure short-term survival. Furthermore, they optimized allocation of the available resource by concentrating biomass and storage to those tissues responsible for assimilation.

  16. Link Monotonic Allocation Schemes

    NARCIS (Netherlands)

    Slikker, M.

    1999-01-01

    A network is a graph where the nodes represent players and the links represent bilateral interaction between the players. A reward game assigns a value to every network on a fixed set of players. An allocation scheme specifies how to distribute the worth of every network among the players. This

  17. Coal + Biomass → Liquids + Electricity (with CCS)

    Science.gov (United States)

    In this presentation, Matt Aitken applies the MARKet ALlocation energy system model to evaluate the market potential for a class of technologies that convert coal and biomass to liquid fuels and electricity (CBtLE), paired with carbon capture and storage (CCS). The technology is ...

  18. Biomass shock pretreatment

    Science.gov (United States)

    Holtzapple, Mark T.; Madison, Maxine Jones; Ramirez, Rocio Sierra; Deimund, Mark A.; Falls, Matthew; Dunkelman, John J.

    2014-07-01

    Methods and apparatus for treating biomass that may include introducing a biomass to a chamber; exposing the biomass in the chamber to a shock event to produce a shocked biomass; and transferring the shocked biomass from the chamber. In some aspects, the method may include pretreating the biomass with a chemical before introducing the biomass to the chamber and/or after transferring shocked biomass from the chamber.

  19. Optimal defense resource allocation in scale-free networks

    Science.gov (United States)

    Zhang, Xuejun; Xu, Guoqiang; Xia, Yongxiang

    2018-02-01

    The robustness research of networked systems has drawn widespread attention in the past decade, and one of the central topics is to protect the network from external attacks through allocating appropriate defense resource to different nodes. In this paper, we apply a specific particle swarm optimization (PSO) algorithm to optimize the defense resource allocation in scale-free networks. Results reveal that PSO based resource allocation shows a higher robustness than other resource allocation strategies such as uniform, degree-proportional, and betweenness-proportional allocation strategies. Furthermore, we find that assigning less resource to middle-degree nodes under small-scale attack while more resource to low-degree nodes under large-scale attack is conductive to improving the network robustness. Our work provides an insight into the optimal defense resource allocation pattern in scale-free networks and is helpful for designing a more robust network.

  20. Tests of sex allocation theory in simultaneously hermaphroditic animals.

    Science.gov (United States)

    Schärer, Lukas

    2009-06-01

    Sex allocation is a crucial life-history parameter in all sexual organisms. Over the last decades a body of evolutionary theory, sex allocation theory, was developed, which has yielded capital insight into the evolution of optimal sex allocation patterns and adaptive evolution in general. Most empirical work, however, has focused on species with separate sexes. Here I review sex allocation theory for simultaneous hermaphrodites and summarize over 50 empirical studies, which have aimed at evaluating this theory in a diversity of simultaneous hermaphrodites spanning nine animal phyla. These studies have yielded considerable qualitative support for several predictions of sex allocation theory, such as a female-biased sex allocation when the number of mates is limited, and a shift toward a more male-biased sex allocation with increasing numbers of mates. In contrast, many fundamental assumptions, such as the trade-off between male and female allocation, and numerous predictions, such as brooding limiting the returns from female allocation, are still poorly supported. Measuring sex allocation in simultaneously hermaphroditic animals remains experimentally demanding, which renders evaluation of more quantitative predictions a challenging task. I identify the main questions that need to be addressed and point to promising avenues for future research.

  1. Edge effects on growth and biomass partitioning of an Amazonian understory herb (Heliconia acuminata; Heliconiaceae).

    Science.gov (United States)

    Bruna, Emilio M; de Andrade, Ana Segalin

    2011-10-01

    After deforestation, environmental changes in the remaining forest fragments are often most intense near the forest edge, but few studies have evaluated plant growth or plasticity of plant growth in response to edge effects. In a 2-year common garden experiment, we compared biomass allocation and growth of Heliconia acuminata with identical genotypes grown in 50 × 35 m common gardens on a 25-year-old edge and in a forest interior site. Genetically identical plants transplanted to the forest edge and understory exhibited different patterns of growth and biomass allocation. However, individuals with identical genotypes in the same garden often had very different responses. Plants on forest edges also had higher growth rates and increased biomass at the end of the experiment, almost certainly due to the increased light on the forest edge. With over 70000 km of forest edge created annually in the Brazilian Amazon, phenotypic plasticity may play an important role in mediating plant responses to these novel environmental conditions.

  2. Applied cost allocation

    DEFF Research Database (Denmark)

    Bogetoft, Peter; Hougaard, Jens Leth; Smilgins, Aleksandrs

    2016-01-01

    This paper deals with empirical computation of Aumann–Shapley cost shares for joint production. We show that if one uses a mathematical programing approach with its non-parametric estimation of the cost function there may be observations in the data set for which we have multiple Aumann–Shapley p...... of assumptions concerning firm behavior. These assumptions enable us to connect inefficient with efficient production and thereby provide consistent ways of allocating the costs arising from inefficiency....

  3. Physiological, morphological and allocational plasticity in understory deciduous trees: importance of plant size and light availability.

    Science.gov (United States)

    Delagrange, Sylvain; Messier, Christian; Lechowicz, Martin J; Dizengremel, Pierre

    2004-07-01

    In a 4-year study, we investigated changes in leaf physiology, crown morphology and whole-tree biomass allocation in seedlings and saplings of shade-tolerant sugar maple (Acer saccharum Marsh.) and intermediate shade-tolerant yellow birch (Betula alleghaniensis Britt.) growing in natural understory light (0.5 to 35% of full sunlight) or in understory light reduced by 50% with shade nets to simulate the effect of gap closure. Leaf physiological parameters were mainly influenced by the light gradient, whereas crown morphological and whole-tree allocational parameters were mainly influenced by tree size. No single physiological, morphological or allocational trait was identified that could explain the difference in shade tolerance between the species. Yellow birch had higher growth rates, biomass allocation to branches and leaf physiological plasticity and lower crown morphological plasticity in unmodified understory light than sugar maple. Sugar maple did not display significant physiological plasticity, but showed variation with tree size in both crown morphology and whole-tree biomass allocation. When sugar maple was small, a greater proportion of whole-tree biomass was allocated to roots. However, physiological differences between the species decreased with decreasing light and most morphological and allocational differences tended to disappear with increasing tree size, suggesting that many species differences in shade-tolerance are expressed mainly during the seedling stage. Understory trees of both species survived for 4 years under shade nets, possibly because of higher plasticity when small and the use of stored reserves when taller. Copyright 2004 Heron Publishing

  4. Dynamic preferential allocation to arbuscular mycorrhizal fungi explains fungal succession and coexistence.

    Science.gov (United States)

    Bachelot, Benedicte; Lee, Charlotte T

    2018-02-01

    Evidence accumulates about the role of arbuscular mycorrhizal (AM) fungi in shaping plant communities, but little is known about the factors determining the biomass and coexistence of several types of AM fungi in a plant community. Here, using a consumer-resource framework that treats the relationship between plants and fungi as simultaneous, reciprocal exploitation, we investigated what patterns of dynamic preferential plant carbon allocation to empirically-defined fungal types (on-going partner choice) would be optimal for plants, and how these patterns depend on successional dynamics. We found that ruderal AM fungi can dominate under low steady-state nutrient availability, and competitor AM fungi can dominate at higher steady-state nutrient availability; these are conditions characteristic of early and late succession, respectively. We also found that dynamic preferential allocation alone can maintain a diversity of mutualists, suggesting that on-going partner choice is a new coexistence mechanism for mutualists. Our model can therefore explain both mutualist coexistence and successional strategy, providing a powerful tool to derive testable predictions. © 2017 by the Ecological Society of America.

  5. Cost allocation with limited information

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tind, Jørgen

    This article investigates progressive development of Aumann-Shapley cost allocation in a multilevel organizational or production structure. In particular, we study a linear parametric programming setup utilizing the Dantzig-Wolfe decomposition procedure. Typically cost allocation takes place after...... all activities have been performed, for example by finishing all outputs. Here the allocation is made progressively with suggestions for activities. I other words cost allocation is performed in parallel for example with a production planning process. This development does not require detailed...

  6. Density-dependent reproductive and vegetative allocation in the aquatic plant Pistia stratiotes (Araceae

    Directory of Open Access Journals (Sweden)

    Flávia Freitas Coelho

    2005-09-01

    Full Text Available Pistia stratiotes is an aquatic macrophyte that grows in temporary-ponds in the southern Pantanal, Brazil. It reproduces both sexually and asexually and is usually observed forming dense mats on the water surface, a condition favored by the plant’s vegetative reproduction coupled with an ability for rapid growth. In this study we examined the effect of densely crowded conditions on the production of reproductive and vegetative structures. In addition, we verified whether there is a trade-off between clonal growth and investment in sexual reproductive structures, and whether there is an allocation pattern with plant size. Individual plant biomass and the number of the rosettes producing sexual reproductive structures and vegetative growth structures both increased with density. Increase in plant size resulted in increased proportional allocation to sexual reproductive structures and vegetative growth structures. Allocation of biomass to reproduction did not occur at the expense of clonal growth. Thus, the density response appears as a increase of rosettes producing sexual reproductive structures and vegetative growth structures. Therefore, long leaves and stolons may be adaptive under densely crowded conditions where competition for light is intense. An important aspect in the study of trade-offs is the size-dependency of the allocation patterns .Usually, larger plants produce more biomass. Therefore, larger plants can allocate more biomass to both vegetative and sexual reproduction than smaller plants and thus show a positive correlation between both traits rather than the expected negative one. Rev. Biol. Trop. 53(3-4: 369-376. Epub 2005 Oct 3.Pistias strariotes es una macrófita acuática que crece en charcas estacionales en el Pantanal sureño de Brasil. Se reproduce tanto sexual como asexualmente y se obsrva generalmente que forma densas parches sobre la superficie del agua, una condicion que favorecida por la reproduccion vegetativa de la

  7. SSC accelerator availability allocation

    International Nuclear Information System (INIS)

    Dixon, K.T.; Franciscovich, J.

    1991-03-01

    Superconducting Super Collider (SSC) operational availability is an area of major concern, judged by the Central Design Group to present such risk that use of modern engineering tools would be essential to program success. Experience has shown that as accelerator beam availability falls below about 80%, efficiency of physics experiments degrades rapidly due to inability to maintain adequate coincident accelerator and detector operation. For this reason, the SSC availability goal has been set at 80%, even though the Fermi National Accelerator Laboratory accelerator, with a fraction of the SSC's complexity, has only recently approached that level. This paper describes the allocation of the top-level goal to part-level reliability and maintainability requirements, and it gives the results of parameter sensitivity studies designed to help identify the best approach to achieve the needed system availability within funding and schedule constraints. 1 ref., 12 figs., 4 tabs

  8. Biomass torrefaction mill

    Science.gov (United States)

    Sprouse, Kenneth M.

    2016-05-17

    A biomass torrefaction system includes a mill which receives a raw biomass feedstock and operates at temperatures above 400 F (204 C) to generate a dusty flue gas which contains a milled biomass product.

  9. Genomics Mechanisms of Carbon Allocation and Partitioning in Poplar

    Energy Technology Data Exchange (ETDEWEB)

    Kirst, Matias; Peter, Gary; Martin, Timothy

    2009-07-30

    The genetic control of carbon allocation and partitioning in woody perennial plants is poorly understood despite its importance for carbon sequestration. It is also unclear how environmental cues such as nitrogen availability impact the genes that regulate growth, and biomass allocation and wood composition in trees. To address these questions we phenotyped 396 clonally replicated genotypes of an interspecific pseudo-backcross pedigree of Populus for wood composition and biomass traits in above and below ground organs. The loci that regulate growth, carbon allocation and partitioning under two nitrogen conditions were identified, defining the contribution of environmental cues to their genetic control. Fifty-seven quantitative trait loci (QTL) were identified for twenty traits analyzed. The majority of QTL are specific to one of the two nitrogen treatments, demonstrating significant nitrogen-dependent genetic control. A highly significant genetic correlation was observed between plant growth and lignin/cellulose composition, and QTL co-localization identified the genomic position of potential pleiotropic regulators. Gene expression analysis of all poplar genes was also characterized in differentiating xylem, whole-roots and developing leaves of 192 of the segregating population. By integrating the QTL and gene expression information we identified genes that regulate carbon partitioning and several biomass growth related properties. The work developed in this project resulted in the publication of three book chapters, four scientific articles (three others currently in preparation), 17 presentations in international conferences and two provisional patent applications.

  10. Importance measures and resource allocation

    International Nuclear Information System (INIS)

    Guey, C.N.; Morgan, T.; Hughes, E.A.

    1987-01-01

    This paper discusses various importance measures and their practical relevance to allocating resources. The characteristics of importance measures are illustrated through simple examples. Important factors associated with effectively allocating resources to improve plant system performance or to prevent system degradation are discussed. It is concluded that importance measures are only indicative of and not equal to the risk significance of a component, system, or event. A decision framework is suggested to provide a comprehensive basis for resource allocation

  11. Early Root Herbivory Impairs Arbuscular Mycorrhizal Fungal Colonization and Shifts Defence Allocation in Establishing Plantago lanceolata.

    Science.gov (United States)

    Bennett, Alison E; Macrae, Anna M; Moore, Ben D; Caul, Sandra; Johnson, Scott N

    2013-01-01

    Research into plant-mediated indirect interactions between arbuscular mycorrhizal (AM) fungi and insect herbivores has focussed on those between plant shoots and above-ground herbivores, despite the fact that only below-ground herbivores share the same part of the host plant as AM fungi. Using Plantago lanceolata L., we aimed to characterise how early root herbivory by the vine weevil (Otiorhynchus sulcatus F.) affected subsequent colonization by AM fungi (Glomus spp.) and determine how the two affected plant growth and defensive chemistry. We exposed four week old P. lanceolata to root herbivory and AM fungi using a 2×2 factorial design (and quantified subsequent effects on plant biomass and iridoid glycosides (IGs) concentrations. Otiorhynchus sulcatus reduced root growth by c. 64%, whereas plant growth was unaffected by AM fungi. Root herbivory reduced extent of AM fungal colonization (by c. 61%). O. sulcatus did not influence overall IG concentrations, but caused qualitative shifts in root and shoot IGs, specifically increasing the proportion of the more toxic catalpol. These changes may reflect defensive allocation in the plant against further attack. This study demonstrates that very early root herbivory during plant development can shape future patterns of AM fungal colonization and influence defensive allocation in the plant.

  12. Efficient Metropolitan Resource Allocation

    Directory of Open Access Journals (Sweden)

    Richard Arnott

    2016-05-01

    Full Text Available Over the past 30 years Calgary has doubled in size, from a population of 640,645 in 1985 to 1,230,915 in 2015. During that time the City has had five different mayors, hosted the Winter Olympics, and expanded the C-Train from 25 platforms to 45. Calgary’s Metropolitan Area has grown too, with Airdrie, Chestermere, Okotoks and Cochrane growing into full-fledged cities, ripe with inter-urban commuters.* And with changes to provincial legislation in the mid-’90s, rural Rocky View County and the Municipal District of Foothills are now real competitors for residential, commercial and industrial development that in the past would have been considered urban. In this metropolitan system, where people live, their household structure, and their place of work informs the services they need to conduct their daily lives, and directly impacts the spatial character of the City and the broader region. In sum, Metropolitan Calgary is increasingly complex. Calgary and the broader metropolitan area will continue to grow, even with the current economic slowdown. Frictions within Calgary, between the various municipalities in the metropolitan area, and the priorities of other local authorities (such as the School Boards and Alberta Health Services will continue to impact the agendas of local politicians and their ability to answer to the needs of their residents. How resources – whether it is hard infrastructure, affordable housing, classrooms, or hospital beds – are allocated over space and how these resources are funded, directly impacts these relationships. This technical paper provides my perspective as an urban economist on the efficient allocation of resources within a metropolitan system in general, with reference to Calgary where appropriate, and serves as a companion to the previously released “Reflections on Calgary’s Spatial Structure: An Urban Economists Critique of Municipal Planning in Calgary.” It is hoped that the concepts reviewed

  13. Spatial pattern of a fish assemblage in a seasonal tropical wetland: effects of habitat, herbaceous plant biomass, water depth, and distance from species sources

    Directory of Open Access Journals (Sweden)

    Izaias M Fernandes

    Full Text Available The influence of habitat, biomass of herbaceous vegetation, depth and distance from permanent water bodies on the structure of fish assemblages of a seasonal floodplain was evaluated using data collected along 22 transects in an area of 25 km² in the floodplain of Cuiabá River, Pantanal, Brazil. Each transect was sampled for fish using throw traps and gillnets during the flood period of 2006. Multivariate multiple regression analysis and multivariate analysis of covariance indicated that depth was the only variable that affected the structure of the fish assemblage, both for quantitative data (abundance and qualitative data (presence-absence. Species such as Neofundulus parvipinnis and Laetacara dorsigera were more abundant in shallower sites (below 25 cm, while Serrasalmus maculatus and Metynnis mola were found mostly in the deepest areas (over 55 cm. However, species such as Hoplias malabaricus and Hoplerythrinus unitaeniatus occurred at all sampled depths. Although the distribution of most species was restricted to a few sites, there was a positive relationship between species richness and depth of the water body. Surprisingly, the replacement of native vegetation by exotic pasture did not affect the fish assemblage in the area, at the probability level considered.

  14. Comparison fermentation kinetics (in vitro of grass and shrub legume leaves: The pattern of VFA concentration, estimated CH4 and microbial biomass production

    Directory of Open Access Journals (Sweden)

    Y Widiawati

    2007-06-01

    Full Text Available In the process of fermentation, rumen microbes normally convert major fractions of carbohydrates and proteins in a feed to useful end-products (i.e. VFA, microbial protein and B-vitamins and some waste products (i.e. CH4 and CO2. The pattern of these end-products depend largely on the fraction contained in the feed eaten by the animal. Two types of feeds, namely grass and shrub legume, leucaena have different fraction proportions. Grass contains more fibre but less protein compared to shrub legumes. Thus in the rumen they might be fermented to produce different pattern of end products. The experiment was conducted in order to examine the pattern of VFA, CH4 and microbial protein products of the two types of feeds when fermented in the rumen. In vitro method was used to determine the pattern of these end products. Results showed that the grass produced more total VFA/mg organic matter degraded (0.0229 mM/mg vs 0.0075 mM/mg and CH4 gas (0.20 mole/mg vs 0.09 mole/mg but less propionate in partial and less microbial protein (2646 g vs 2656 g compared to the legume. Approximately 32% less CH4 (per mg OM degraded would be produced from leucaena compared to that produced from grass, which mean that there will be less energy loss as CH4 thus more energy for animal production.

  15. Water depth affects reproductive allocation and reproductive allometry in the submerged macrophyte Vallisneria natans.

    Science.gov (United States)

    Li, Lei; Bonser, Stephen P; Lan, Zhichun; Xu, Ligang; Chen, Jiakuan; Song, Zhiping

    2017-12-04

    In freshwater ecosystems, shifts in hydrological regimes have profound effects on reproductive output (R), along with vegetative biomass (V) and survival of plants. Because reproductive allocation (RA) is allometric, it remains unclear whether the observed variation of RA in response to water level variability is due to fixed patterns of development or plasticity in the developmental trajectories. Here, we investigated shifts in RA of a submerged macrophyte Vallisneria natans in response to water depth to test the hypothesis that allometric trajectories of RA are highly plastic. Plants were grown at three water depths (50, 100 and 150 cm) and measured after 26 weeks of growth. The relationships between R and V among treatments were compared. Deep water affected both biomass and number of fruits produced per plant, leading to less sexual reproduction. Plants in deep water started flowering at a smaller size and despite their small mature size, had a relatively high RA. Furthermore, these plants had a much lower log R-log V relationship than shallow- or intermediate-water plants. In conclusion, reproduction of V. natans is highly variable across water depth treatments, and variations in reproductive allometry represent different strategies under an important stress gradient for these freshwater angiosperms.

  16. Alterações morfológicas e alocação de biomassa em plantas jovens de espécies florestais sob diferentes condições de sombreamento Morphologic alterations and biomass allocation in young plants of forestry species under different conditions of shading

    Directory of Open Access Journals (Sweden)

    Silvia Mara Zanela Almeida

    2005-02-01

    Full Text Available A seleção de espécies nativas e/ou exóticas para recuperação de ambientes degradados ou alterados pode ser baseada no potencial de aclimatação das espécies a diferentes níveis de luminosidade. Nesse contexto, o objetivo deste estudo foi avaliar o efeito do sombreamento (0%, 30% e 50% de interceptação da radiação solar incidente no crescimento, na alocação de biomassa e nos teores de clorofila total de plantas jovens de quatro espécies florestais de diferentes grupos ecológicos: Maclura tinctoria (L. D. Don ex Steud. (moreira, Senna macranthera (Collad. Irwin et Barn. (fedegoso, Hymenaea courbaril L. var. stilbocarpa (Hayne Lee et Lang. (jatobá e Acacia mangium Willd. (acácia. Os maiores teores de clorofila total foram observados em condições sombreadas, para todas as espécies. A espécie clímax exigente em luz (moreira, apresentou os maiores resultados de crescimento. Em condições de pleno sol, a espécie pioneira (acácia alocou mais biomassa em folhas enquanto que a espécie clímax exigente em luz (moreira produziu mais raízes. Estas observações evidenciam o potencial de aclimatação a diferentes condições de disponibilidade de irradiação, que deve ser considerado em programas de recuperação de ambientes degradados e manejo de áreas naturais.The selection of native and/or exotic species for recovery of degraded or perturbed environment can be associated with the acclimatation potential of species in different conditions of shading. In this context, the objective of this research was to evaluate the effect of shading (0%, 30% and 50% of interception of the incident solar radiation on growth, biomass allocation and chlorophyll levels in young plants of forestry species from different ecological groups: Maclura tinctoria (L. D. Don ex Steud. (moreira, Senna macranthera (Collad. Irwin et Barn. (fedegoso, Hymenaea courbaril L. var. stilbocarpa (Hayne Lee et Lang. (jatobá e Acacia mangium Willd. (acácia. The

  17. Risk allocation under liquidity constraints

    NARCIS (Netherlands)

    Csóka, P.; Herings, P.J.J.

    2013-01-01

    Risk allocation games are cooperative games that are used to attribute the risk of a financial entity to its divisions. In this paper, we extend the literature on risk allocation games by incorporating liquidity considerations. A liquidity policy specifies state-dependent liquidity requirements that

  18. Variation in allocation of time, water and energy in Hoopoe Larks from the Arabian Desert

    NARCIS (Netherlands)

    Tieleman, BI; Williams, JB; Visser, GH

    2003-01-01

    1. Patterns of resource allocation in different times of the year can provide insights into the effects of simultaneous environmental constraints on reproduction and survival of desert birds. Field metabolic rate (FMR), water influx rate (WIR) and patterns of time allocation of Hoopoe Larks (Alaemon

  19. Sharing the wealth: factors influencing resource allocation in the sharing game.

    Science.gov (United States)

    Fantino, Edmund; Kennelly, Arthur

    2009-05-01

    Students chose between two allocation options, one that gave the allocator more and another participant still more (the "optimal" choice) and one which gave the allocator less and the other participant still less (the "competitive" choice). In a within-subjects design, students' behavior patterns were significantly correlated across the two rounds of decision-making; however, students allocated more optimally when the allocation involved real rather than hypothetical money, suggesting that both motivational context and individuals' personality and/or experience influence preference patterns. The nature of the putative other participant did not affect the allocation: students allocated in a comparable fashion whether the other participant was said to be male, female, or a computer.

  20. Rheology of concentrated biomass

    Science.gov (United States)

    J.R. Samaniuk; J. Wang; T.W. Root; C.T. Scott; D.J. Klingenberg

    2011-01-01

    Economic processing of lignocellulosic biomass requires handling the biomass at high solids concentration. This creates challenges because concentrated biomass behaves as a Bingham-like material with large yield stresses. Here we employ torque rheometry to measure the rheological properties of concentrated lignocellulosic biomass (corn stover). Yield stresses obtained...

  1. Biomass treatment method

    Science.gov (United States)

    Friend, Julie; Elander, Richard T.; Tucker, III; Melvin P.; Lyons, Robert C.

    2010-10-26

    A method for treating biomass was developed that uses an apparatus which moves a biomass and dilute aqueous ammonia mixture through reaction chambers without compaction. The apparatus moves the biomass using a non-compressing piston. The resulting treated biomass is saccharified to produce fermentable sugars.

  2. Methods for pretreating biomass

    Science.gov (United States)

    Balan, Venkatesh; Dale, Bruce E; Chundawat, Shishir; Sousa, Leonardo

    2017-05-09

    A method for pretreating biomass is provided, which includes, in a reactor, allowing gaseous ammonia to condense on the biomass and react with water present in the biomass to produce pretreated biomass, wherein reactivity of polysaccharides in the biomass is increased during subsequent biological conversion as compared to the reactivity of polysaccharides in biomass which has not been pretreated. A method for pretreating biomass with a liquid ammonia and recovering the liquid ammonia is also provided. Related systems which include a biochemical or biofuel production facility are also disclosed.

  3. CO-FIRING COAL: FEEDLOT AND LITTER BIOMASS FUELS

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Kalyan Annamalai; Dr. John Sweeten; Dr. Sayeed Mukhtar

    2000-10-24

    The following are proposed activities for quarter 1 (6/15/00-9/14/00): (1) Finalize the allocation of funds within TAMU to co-principal investigators and the final task lists; (2) Acquire 3 D computer code for coal combustion and modify for cofiring Coal:Feedlot biomass and Coal:Litter biomass fuels; (3) Develop a simple one dimensional model for fixed bed gasifier cofired with coal:biomass fuels; and (4) Prepare the boiler burner for reburn tests with feedlot biomass fuels. The following were achieved During Quarter 5 (6/15/00-9/14/00): (1) Funds are being allocated to co-principal investigators; task list from Prof. Mukhtar has been received (Appendix A); (2) Order has been placed to acquire Pulverized Coal gasification and Combustion 3 D (PCGC-3) computer code for coal combustion and modify for cofiring Coal: Feedlot biomass and Coal: Litter biomass fuels. Reason for selecting this code is the availability of source code for modification to include biomass fuels; (3) A simplified one-dimensional model has been developed; however convergence had not yet been achieved; and (4) The length of the boiler burner has been increased to increase the residence time. A premixed propane burner has been installed to simulate coal combustion gases. First coal, as a reburn fuel will be used to generate base line data followed by methane, feedlot and litter biomass fuels.

  4. Resource allocation processes at multilateral organizations working in global health.

    Science.gov (United States)

    Chi, Y-Ling; Bump, Jesse B

    2018-02-01

    International institutions provide well over US$10 billion in development assistance for health (DAH) annually and between 1990 and 2014, DAH disbursements totaled $458 billion but how do they decide who gets what, and for what purpose? In this article, we explore how allocation decisions were made by the nine convening agencies of the Equitable Access Initiative. We provide clear, plain language descriptions of the complete process from resource mobilization to allocation for the nine multilateral agencies with prominent agendas in global health. Then, through a comparative analysis we illuminate the choices and strategies employed in the nine international institutions. We find that resource allocation in all reviewed institutions follow a similar pattern, which we categorized in a framework of five steps: strategy definition, resource mobilization, eligibility of countries, support type and funds allocation. All the reviewed institutions generate resource allocation decisions through well-structured and fairly complex processes. Variations in those processes seem to reflect differences in institutional principles and goals. However, these processes have serious shortcomings. Technical problems include inadequate flexibility to account for or meet country needs. Although aid effectiveness and value for money are commonly referenced, we find that neither performance nor impact is a major criterion for allocating resources. We found very little formal consideration of the incentives generated by allocation choices. Political issues include non-transparent influence on allocation processes by donors and bureaucrats, and the common practice of earmarking funds to bypass the normal allocation process entirely. Ethical deficiencies include low accountability and transparency at international institutions, and limited participation by affected citizens or their representatives. We find that recipient countries have low influence on allocation processes themselves

  5. Durability of Biomass Briquettes

    OpenAIRE

    Kaķītis, A.; Nulle, I.

    2006-01-01

    The main resources for biomass agro-ecotechnologies are cereal straw residues, energy crops and emergent vegetation from wetlands. The herbaceous biomass is a material of low density (20 – 60kg/m3) therefore new mobile equipment and technologies for biomass comminution and densification have to be worked out. To guarantee the quality of biomass briquettes in the handling and usage process, sufficient durability of briquettes should be provided. National Standards of biomass briquettes should ...

  6. Transnational Energy Companies' Investment Allocation Decisions

    International Nuclear Information System (INIS)

    Osmundsen, Petter; Emhjellen, Magne; Halleraker, Morten

    2001-10-01

    When making international capital budgeting decisions, energy companies are often faced with capital and organisational constraints. The constraints may be real or management imposed. In addition, when entering into a new country or region the companies will incur fixed new area costs that must be considered before investment approval. The decision problem is therefore not a linear problem where the standard net present value rule applies, but a non-linear problem of selecting the combination of projects with the maximum aggregate net present value. New project investments will therefore be selected based on the size of the net present value (often referred to as financial volume or materiality) compared to the projects' use of capital and scarce personnel and organisational capacity. Consequently, projects with a positive net present value, but with low materiality, may not be approved. The portfolio choice has a parallel to the company's choice of core areas. Instead of complex portfolio models, the companies often apply simpler allocation mechanisms, e.g., combinations of fixed investment budgets and materiality requirements. Analysing petroleum cases, we compare the allocations decisions generated by portfolio models and simpler mechanisms. We also discuss the implications of this capital allocation pattern for governments' design of tax systems and license conditions. (author)

  7. Fast discriminative latent Dirichlet allocation

    Data.gov (United States)

    National Aeronautics and Space Administration — This is the code for fast discriminative latent Dirichlet allocation, which is an algorithm for topic modeling and text classification. The related paper is at...

  8. FY12 CPD Formula Allocation

    Data.gov (United States)

    Department of Housing and Urban Development — The Fiscal Year (FY) 2012 budget for the Department of Housing and Urban Development has been enacted. This spreadsheet provide full-year allocations for the Office...

  9. Biomass partitioning in red pine (Pinus resinosa) along a chronosequence in the Upper Peninsula of Michigan

    Science.gov (United States)

    J.S. King; C.P. Giardina; K.S. Pregitzer; A.L. Friend

    2007-01-01

    Carbon (C) allocation to the perennial coarse-root system of trees contributes to ecosystem C sequestration through formation of long-lived live wood biomass and, following senescence, by providing a large source of nutrient-poor detrital C. Our understanding of the controls on C allocation to coarse-root growth is rudimentary, but it has important implications for...

  10. Tradeoffs around crop residue biomass in smallholder crop-livestock systems - What's next?

    NARCIS (Netherlands)

    Tittonell, P.A.; Gérard, B.; Erenstein, O.

    2015-01-01

    Much has been written on the tradeoffs that smallholder farmers face when having to allocate their biomass resources among competing objectives such as feed, fuel, mulch, compost or the market. This paper summarises yet a new body of evidence from 10 studies on tradeoffs in the allocation of cereal

  11. International Development Aid Allocation Determinants

    OpenAIRE

    Tapas Mishra; Bazoumana Ouattara; Mamata Parhi

    2012-01-01

    This paper investigates the factors explaining aid allocation by bilateral and multilateral donors. We use data for 146 aid recipient countries over the period 1990-2007 and employ Bayesian Averaging of Classical Estimates Approach (BACE) approach and find that both the recipient need and donor interest motives are `significant' determinants of bilateral and multilateral aid allocation process. Our results also indicate that the measures for recipient need and donor interests vary from bilate...

  12. Application of an allocation methodology

    International Nuclear Information System (INIS)

    Youngblood, R.

    1989-01-01

    This paper presents a method for allocating resources to elements of a system for the purpose of achieving prescribed levels of defense-in-depth at minimal cost. The method makes extensive use of logic modelling. An analysis of a simplified high-level waste repository is used as an illustrative application of the method. It is shown that it is possible to allocate quality control costs (or demonstrate performance) in an optimal way over elements of a conceptual design

  13. How should INGOs allocate resources?

    Directory of Open Access Journals (Sweden)

    Scott Wisor

    2012-02-01

    Full Text Available International Non-governmental Organizations (INGOs face difficult choices when choosing to allocate resources. Given that the resources made available to INGOs fall far short of what is needed to reduce massive human rights deficits, any chosen scheme of resource allocation requires failing to reach other individuals in great need. Facing these moral opportunity costs, what moral reasons should guide INGO resource allocation? Two reasons that clearly matter, and are recognized by philosophers and development practitioners, are the consequences (or benefit or harm reduction of any given resource allocation and the need (or priority of individual beneficiaries. If accepted, these reasons should lead INGOs to allocate resources to a limited number of countries where the most prioritarian weighted harm reduction will be achieved. I make three critiques against this view. First, on grounds the consequentialist accepts, I argue that INGOs ought to maintain a reasonably wide distribution of resources. Second, I argue that even if one is a consequentialist, consequentialism ought not act as an action guiding principle for INGOs. Third, I argue that additional moral reasons should influence decision making about INGO resource allocation. Namely, INGO decision making should attend to relational reasons, desert, respect for agency, concern for equity, and the importance of expressing a view of moral wrongs.

  14. Generalized multidimensional dynamic allocation method.

    Science.gov (United States)

    Lebowitsch, Jonathan; Ge, Yan; Young, Benjamin; Hu, Feifang

    2012-12-10

    Dynamic allocation has received considerable attention since it was first proposed in the 1970s as an alternative means of allocating treatments in clinical trials which helps to secure the balance of prognostic factors across treatment groups. The purpose of this paper is to present a generalized multidimensional dynamic allocation method that simultaneously balances treatment assignments at three key levels: within the overall study, within each level of each prognostic factor, and within each stratum, that is, combination of levels of different factors Further it offers capabilities for unbalanced and adaptive designs for trials. The treatment balancing performance of the proposed method is investigated through simulations which compare multidimensional dynamic allocation with traditional stratified block randomization and the Pocock-Simon method. On the basis of these results, we conclude that this generalized multidimensional dynamic allocation method is an improvement over conventional dynamic allocation methods and is flexible enough to be applied for most trial settings including Phases I, II and III trials. Copyright © 2012 John Wiley & Sons, Ltd.

  15. [Spatial distribution pattern and allometric growth of three common species on moving sand dunes in Horqin Sandy Land, China].

    Science.gov (United States)

    Jia, Mei-yu; Li, Xue-hua; Oh, Choong-hyeon; Park, Hong-chul; Miao, Chun-ping; Han, Xu

    2015-10-01

    Research on fine scale pattern and characteristics of allometric growth could contribute to better understanding plants' adaptation in moving sandy dunes. The abundance, height and biomass of 3 species Agriophilum aquarrosum, Corispermum candelabrum and Setaria viridis in twenty-eight 1 m x 1 m quadrats of Horqin Sandy Land were identified, mapped and described. The nearest neighbor method and O-ring O(r) function analysis were applied to analyze the spatial patterns. The results showed that the individual spatial pattern was mainly aggregated in 1 m x 1 m quadrat at community level but mainly random at population level. At 0-50 cm individual distance scale, both intraspecific and interspecific relationship were facilitation and aggregated distribution occurred at some scales and varied with increasing plant abundance in 1 m x 1 m quadrat. In 0-40 cm, the aggregated distribution of S. viridis and A. aquarrosum increased obviously; in 10-20 cm, both intraspecific and interspecific aggregation increased; in 10-30 cm, the occurrence possibility of positive correlations between S. viridis and A. aquarrosum, S. viridis and C. candelabrum all increased; in 40-50 cm, the possibility of positive correlations between A. squarrosum and S. viridis, A. squarrosum and C. candelabrum all increased. Research on the three species components indicated that the growth rate of above-ground was faster than that of underground. S. viridis had the highest ratio of under-ground biomass to above-ground biomass but its nutritional organs' biomass ratio was medium. C. candelabrum allocated more biomass to propagative organs and stem, but A. squarrosum allocated more biomass to nutritional organs. Based on the spatial distribution and allometric characteristics, the three common species in moving sand dunes preferred r strategy in their life history.

  16. Effect of different Planting Pattern of Wheat (Triticum aestivum and Bean (Vicia faba on Grain Yield, Dry Matter Production and Weed Biomass

    Directory of Open Access Journals (Sweden)

    Hamdollah ESKANDARI

    2010-12-01

    Full Text Available An experiment was conducted in University of London, Kent, UK during the year 2003. The aim of experiment was to investigate the effects of planting pattern on performance of wheat and bean intercrops. A complete randomized block design with four replications was employed to compare the treatments. Treatments included wheat sole crop (W, Bean sole crop (B, within row intercropping (M1, row intercropping (M2 and mix cropping (M3. The density of intercropping was according to replacement design (one wheat replaced by three bean plants. The results showed that total dry matter achieved by intercrops was significantly higher than those achieved by either wheat or bean sole crop. Regarding to weed control, intercrops were more effective than sole crops, especially bean sole crop. Crops performance in terms dry weight, height and percentage of leaf, stem pod and ear was affected by cropping systems depending on crop species, where wheat showed more changes compared to bean . Grain yield, harvest index and thousand grain weights of wheat were decreased in intercropping while bean had reduction only in grain yield.

  17. Effects of salt and water stress on plant biomass and photosynthetic ...

    African Journals Online (AJOL)

    Increased soil salt content had no significant effect (p>0.05) on biomass allocation of T. chinensis seedlings, while water deficit significantly favoured root biomass accumulation. T. chinensis seedlings were able to maintain high leaf gas exchange rates under 20% FC, but water use efficiency (WUE) decreased and sufficient ...

  18. TG-FTIR analysis of biomass pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Bassilakis, R.; Carangelo, R.M.; Wojtowicz, M.A. [Advanced Fuel Research Inc., Hartford, CT (United States)

    2001-10-09

    A great need exists for comprehensive biomass-pyrolysis models that could predict yields and evolution patterns of selected volatile products as a function of feedstock characteristics and process conditions. A thermogravimetric analyzer coupled with Fourier transform infrared analysis of evolving products (TG-FTIR) can provide useful input to such models in the form of kinetic information obtained under low heating rate conditions. In this work, robust TG-FTIR quantification routes were developed for infrared analysis of volatile products relevant to biomass pyrolysis. The analysis was applied to wheat straw, three types of tobacco (Burley, Oriental, and Bright) and three biomass model compounds (xylan, chlorogenic acid, and D-glucose). Product yields were compared with literature data, and species potentially quantifiable by FT-IR are reviewed. Product-evolution patterns are reported for all seven biomass samples. 41 refs., 7 figs., 2 tabs.

  19. The Effect of Spectral Quality on Daily Patterns of Gas Exchange, Biomass Gain, and Water-Use-Efficiency in Tomatoes and Lisianthus: An Assessment of Whole Plant Measurements.

    Science.gov (United States)

    Lanoue, Jason; Leonardos, Evangelos D; Ma, Xiao; Grodzinski, Bernard

    2017-01-01

    Advancements in light-emitting diode (LED) technology have made them a viable alternative to current lighting systems for both sole and supplemental lighting requirements. Understanding how wavelength specific LED lighting can affect plants is thus an area of great interest. Much research is available on the wavelength specific responses of leaves from multiple crops when exposed to long-term wavelength specific lighting. However, leaf measurements do not always extrapolate linearly to the complexities which are found within a whole plant canopy, namely mutual shading and leaves of different ages. Taken together, both tomato ( Solanum lycopersicum ) leaves under short-term illumination and lisianthus ( Eustoma grandiflorum ) and tomato whole plant diurnal patterns of plants acclimated to specific lighting indicate wavelength specific responses of both H 2 O and CO 2 gas exchanges involved in the major growth parameters of a plant. Tomato leaves grown under a white light source indicated an increase in transpiration rate and internal CO 2 concentration and a subsequent decrease in water-use-efficiency (WUE) when exposed to a blue LED light source compared to a green LED light source. Interestingly, the maximum photosynthetic rate was observed to be similar. Using plants grown under wavelength specific supplemental lighting in a greenhouse, a decrease in whole plant WUE was seen in both crops under both red-blue (RB) and red-white (RW) LEDs when compared to a high pressure sodium (HPS) light. Whole plant WUE was decreased by 31% under the RB LED treatment for both crops compared to the HPS treatment. Tomato whole plant WUE was decreased by 25% and lisianthus whole plant WUE was decreased by 15% when compared to the HPS treatment when grown under RW LED. The understanding of the effects of wavelength specific lighting on both leaf and whole plant gas exchange has significant implications on basic academic research as well as commercial greenhouse production.

  20. The Effect of Spectral Quality on Daily Patterns of Gas Exchange, Biomass Gain, and Water-Use-Efficiency in Tomatoes and Lisianthus: An Assessment of Whole Plant Measurements

    Directory of Open Access Journals (Sweden)

    Jason Lanoue

    2017-06-01

    Full Text Available Advancements in light-emitting diode (LED technology have made them a viable alternative to current lighting systems for both sole and supplemental lighting requirements. Understanding how wavelength specific LED lighting can affect plants is thus an area of great interest. Much research is available on the wavelength specific responses of leaves from multiple crops when exposed to long-term wavelength specific lighting. However, leaf measurements do not always extrapolate linearly to the complexities which are found within a whole plant canopy, namely mutual shading and leaves of different ages. Taken together, both tomato (Solanum lycopersicum leaves under short-term illumination and lisianthus (Eustoma grandiflorum and tomato whole plant diurnal patterns of plants acclimated to specific lighting indicate wavelength specific responses of both H2O and CO2 gas exchanges involved in the major growth parameters of a plant. Tomato leaves grown under a white light source indicated an increase in transpiration rate and internal CO2 concentration and a subsequent decrease in water-use-efficiency (WUE when exposed to a blue LED light source compared to a green LED light source. Interestingly, the maximum photosynthetic rate was observed to be similar. Using plants grown under wavelength specific supplemental lighting in a greenhouse, a decrease in whole plant WUE was seen in both crops under both red-blue (RB and red-white (RW LEDs when compared to a high pressure sodium (HPS light. Whole plant WUE was decreased by 31% under the RB LED treatment for both crops compared to the HPS treatment. Tomato whole plant WUE was decreased by 25% and lisianthus whole plant WUE was decreased by 15% when compared to the HPS treatment when grown under RW LED. The understanding of the effects of wavelength specific lighting on both leaf and whole plant gas exchange has significant implications on basic academic research as well as commercial greenhouse production.

  1. The Effect of Spectral Quality on Daily Patterns of Gas Exchange, Biomass Gain, and Water-Use-Efficiency in Tomatoes and Lisianthus: An Assessment of Whole Plant Measurements

    Science.gov (United States)

    Lanoue, Jason; Leonardos, Evangelos D.; Ma, Xiao; Grodzinski, Bernard

    2017-01-01

    Advancements in light-emitting diode (LED) technology have made them a viable alternative to current lighting systems for both sole and supplemental lighting requirements. Understanding how wavelength specific LED lighting can affect plants is thus an area of great interest. Much research is available on the wavelength specific responses of leaves from multiple crops when exposed to long-term wavelength specific lighting. However, leaf measurements do not always extrapolate linearly to the complexities which are found within a whole plant canopy, namely mutual shading and leaves of different ages. Taken together, both tomato (Solanum lycopersicum) leaves under short-term illumination and lisianthus (Eustoma grandiflorum) and tomato whole plant diurnal patterns of plants acclimated to specific lighting indicate wavelength specific responses of both H2O and CO2 gas exchanges involved in the major growth parameters of a plant. Tomato leaves grown under a white light source indicated an increase in transpiration rate and internal CO2 concentration and a subsequent decrease in water-use-efficiency (WUE) when exposed to a blue LED light source compared to a green LED light source. Interestingly, the maximum photosynthetic rate was observed to be similar. Using plants grown under wavelength specific supplemental lighting in a greenhouse, a decrease in whole plant WUE was seen in both crops under both red-blue (RB) and red-white (RW) LEDs when compared to a high pressure sodium (HPS) light. Whole plant WUE was decreased by 31% under the RB LED treatment for both crops compared to the HPS treatment. Tomato whole plant WUE was decreased by 25% and lisianthus whole plant WUE was decreased by 15% when compared to the HPS treatment when grown under RW LED. The understanding of the effects of wavelength specific lighting on both leaf and whole plant gas exchange has significant implications on basic academic research as well as commercial greenhouse production. PMID:28676816

  2. Pretreated densified biomass products

    Science.gov (United States)

    Dale, Bruce E; Ritchie, Bryan; Marshall, Derek

    2014-03-18

    A product comprising at least one densified biomass particulate of a given mass having no added binder and comprised of a plurality of lignin-coated plant biomass fibers is provided, wherein the at least one densified biomass particulate has an intrinsic density substantially equivalent to a binder-containing densified biomass particulate of the same given mass and h a substantially smooth, non-flakey outer surface. Methods for using and making the product are also described.

  3. Cost allocation in distribution planning

    Energy Technology Data Exchange (ETDEWEB)

    Engevall, S.

    1996-12-31

    This thesis concerns cost allocation problems in distribution planning. The cost allocation problems we study are illustrated using the distribution planning situation at the Logistics department of Norsk Hydro Olje AB. The planning situation is modeled as a Traveling Salesman Problem and a Vehicle Routing Problem with an inhomogeneous fleet. The cost allocation problems are the problems of how to divide the transportation costs among the customers served in each problem. The cost allocation problems are formulated as cooperative games, in characteristic function form, where the customers are defined to be the players. The games contain five and 21 players respectively. Game theoretical solution concepts such as the core, the nucleolus, the Shapley value and the {tau}-value are discussed. From the empirical results we can, among other things, conclude that the core of the Traveling Salesman Game is large, and that the core of the Vehicle Routing Game is empty. In the accounting of Norsk Hydro the cost per m{sup 3} can be found for each tour. We conclude that for a certain definition of the characteristic function, a cost allocation according to this principle will not be included in the core of the Traveling Salesman Game. The models and methods presented in this thesis can be applied to transportation problems similar to that of Norsk Hydro, independent of the type of products that are delivered. 96 refs, 11 figs, 26 tabs

  4. Cost allocation in distribution planning

    International Nuclear Information System (INIS)

    Engevall, S.

    1996-01-01

    This thesis concerns cost allocation problems in distribution planning. The cost allocation problems we study are illustrated using the distribution planning situation at the Logistics department of Norsk Hydro Olje AB. The planning situation is modeled as a Traveling Salesman Problem and a Vehicle Routing Problem with an inhomogeneous fleet. The cost allocation problems are the problems of how to divide the transportation costs among the customers served in each problem. The cost allocation problems are formulated as cooperative games, in characteristic function form, where the customers are defined to be the players. The games contain five and 21 players respectively. Game theoretical solution concepts such as the core, the nucleolus, the Shapley value and the τ-value are discussed. From the empirical results we can, among other things, conclude that the core of the Traveling Salesman Game is large, and that the core of the Vehicle Routing Game is empty. In the accounting of Norsk Hydro the cost per m 3 can be found for each tour. We conclude that for a certain definition of the characteristic function, a cost allocation according to this principle will not be included in the core of the Traveling Salesman Game. The models and methods presented in this thesis can be applied to transportation problems similar to that of Norsk Hydro, independent of the type of products that are delivered. 96 refs, 11 figs, 26 tabs

  5. Carbon limitation reveals allocation priority to defense compounds in peppermint

    Science.gov (United States)

    Forkelova, Lenka; Unsicker, Sybille; Forkel, Matthias; Huang, Jianbei; Trumbore, Susan; Hartmann, Henrik

    2016-04-01

    Studies of carbon partitioning during insect or pathogen infestation reveal high carbon investment into induced chemical defenses to deter the biotic agent (Baldwin, 1998). However, little is known how carbon investment into chemical defenses changes under abiotic stress such as drought. Drought forces plants to close their stomata to prevent water loss through transpiration while decreasing the amount of assimilated carbon. Furthermore drought hampers carbohydrates translocation due to declining plant hydration and reduced phloem functioning (McDowell, 2011; Hartmann et al., 2013; Sevanto, 2014). Hence long lasting drought can force plants into carbon starvation. The aim of our study was to disentangle carbon allocation priorities between growth, maintenance metabolism, storage and production of defense compounds under carbon limiting conditions using peppermint as our model plant. Drought is not the only method how to manipulate plant carbon metabolism and photosynthetic yield. Exposing plants to reduced [CO2] air is a promising tool simulating drought induced carbon limitation without affecting phloem functioning and so carbohydrate translocation (Hartmann et al., 2015). We exposed peppermint plants to drought (50% of the control irrigation) and to low [CO2] (progressive decrease from 350 ppm to 20 ppm) to disentangle hydraulic failure from carbon starvation effects on carbon allocation. Drought was applied as a cross-treatment yielding four treatments: watered and high [CO2] (W+CO2), drought and high [CO2] (D+CO2), water and low [CO2] (W-CO2), drought and low [CO2] (D-CO2). We analyzed the most abundant terpenoid defense compounds (α-Pinene, sabinene, myrcene, limonene, menthone, menthol and pulegone) and used continuous 13CO2 labelling to trace allocation pattern of new and old assimilated carbon in the four carbon sinks (structural biomass, water soluble sugars, starch and terpenoid defense compounds) in young expanding leaf tissue. This leaf tissue grew

  6. Faculty Time Allocation: A Study of Change over Twenty Years.

    Science.gov (United States)

    Milem, Jeffrey F.; Berger, Joseph B.; Dey, Eric L.

    2000-01-01

    Examined changes in amounts of time faculty spent in teaching, advising, and research activities over the past 20 years. Found institutions are becoming more similar in their patterns of faculty time allocation, particularly regarding time spend on research. However, time spent advising and interacting informally with students appears to be…

  7. Centralized Allocation in Multiple Markets

    DEFF Research Database (Denmark)

    Monte, Daniel; Tumennasan, Norovsambuu

    The problem of allocating indivisible objects to different agents, where each indi vidual is assigned at most one object, has been widely studied. Pápai (2000) shows that the set of strategy-proof, nonbossy, Pareto optimal and reallocation-proof rules are hierarchical exchange rules | generalizat......The problem of allocating indivisible objects to different agents, where each indi vidual is assigned at most one object, has been widely studied. Pápai (2000) shows that the set of strategy-proof, nonbossy, Pareto optimal and reallocation-proof rules are hierarchical exchange rules...... | generalizations of Gale's Top Trading Cycles mechanism. We study the centralized allocation that takes place in multiple markets. For example, the assignment of multiple types of indivisible objects; or the assignment of objects in successive periods. We show that the set of strategy-proof, Pareto efficient...

  8. Preserving the allocation ratio at every allocation with biased coin randomization and minimization in studies with unequal allocation.

    Science.gov (United States)

    Kuznetsova, Olga M; Tymofyeyev, Yevgen

    2012-04-13

    The demand for unequal allocation in clinical trials is growing. Most commonly, the unequal allocation is achieved through permuted block randomization. However, other allocation procedures might be required to better approximate the allocation ratio in small samples, reduce the selection bias in open-label studies, or balance on baseline covariates. When these allocation procedures are generalized to unequal allocation, special care is to be taken to preserve the allocation ratio at every allocation step. This paper offers a way to expand the biased coin randomization to unequal allocation that preserves the allocation ratio at every allocation. The suggested expansion works with biased coin randomization that balances only on treatment group totals and with covariate-adaptive procedures that use a random biased coin element at every allocation. Balancing properties of the allocation ratio preserving biased coin randomization and minimization are described through simulations. It is demonstrated that these procedures are asymptotically protected against the shift in the rerandomization distribution identified for some examples of minimization with 1:2 allocation. The asymptotic shift in the rerandomization distribution of the difference in treatment means for an arbitrary unequal allocation procedure is explicitly derived in the paper. Copyright © 2011 John Wiley & Sons, Ltd.

  9. Allocation Problems and Market Design

    DEFF Research Database (Denmark)

    Smilgins, Aleksandrs

    The thesis contains six independent papers with a common theme: Allocation problems and market design. The first paper is concerned with fair allocation of risk capital where independent autonomous subunits have risky activities and together constitute the entity's total risk, whose associated risk......-to-one matching model by including a set of objects, such that a matching consists of two agents from disjoint sets, and an object. Agents' preference lists consist of all possible pairs of objects and agents from the other set, and thus contain important information about agent-object tradeoffs. The notion...

  10. Allometric biomass equations for 12 tree species in coniferous and broadleaved mixed forests, Northeastern China.

    Science.gov (United States)

    He, Huaijiang; Zhang, Chunyu; Zhao, Xiuhai; Fousseni, Folega; Wang, Jinsong; Dai, Haijun; Yang, Song; Zuo, Qiang

    2018-01-01

    Understanding forest carbon budget and dynamics for sustainable resource management and ecosystem functions requires quantification of above- and below-ground biomass at individual tree species and stand levels. In this study, a total of 122 trees (9-12 per species) were destructively sampled to determine above- and below-ground biomass of 12 tree species (Acer mandshuricum, Acer mono, Betula platyphylla, Carpinus cordata, Fraxinus mandshurica, Juglans mandshurica, Maackia amurensis, P. koraiensis, Populus ussuriensis, Quercus mongolica, Tilia amurensis and Ulmus japonica) in coniferous and broadleaved mixed forests of Northeastern China, an area of the largest natural forest in the country. Biomass allocation was examined and biomass models were developed using diameter as independent variable for individual tree species and all species combined. The results showed that the largest biomass allocation of all species combined was on stems (57.1%), followed by coarse root (21.3%), branch (18.7%), and foliage (2.9%). The log-transformed model was statistically significant for all biomass components, although predicting power was higher for species-specific models than for all species combined, general biomass models, and higher for stems, roots, above-ground biomass, and total tree biomass than for branch and foliage biomass. These findings supplement the previous studies on this forest type by additional sample trees, species and locations, and support biomass research on forest carbon budget and dynamics by management activities such as thinning and harvesting in the northeastern part of China.

  11. Biomass valorization; La valorisation de la biomasse

    Energy Technology Data Exchange (ETDEWEB)

    Knoll, M. [Groupe d' Analyse Thematique (France)

    2006-09-15

    Biomass is the photosynthesis product of carbon dioxide and water, made by the solar energy capture by plants (CO{sub 2} + H{sub 2}O + solar energy hydrocarbons). It is this carbon which, at the end of the cycle, after fossilization, gives petroleum, gas and coal. But before being in this state, the biomass deposits are diversified and available all over the world. (O.M.)

  12. A bottom-up approach of stochastic demand allocation in water quality modelling

    NARCIS (Netherlands)

    Blokker, E.J.M.; Vreeburg, J.H.G.; Beverloo, H.; Klein Arfman, M.; Van Dijk, J.C.

    2010-01-01

    An “all pipes” hydraulic model of a drinking water distribution system was constructed with two types of demand allocations. One is constructed with the conventional top-down approach, i.e. a demand multiplier pattern from the booster station is allocated to all demand nodes with a correction factor

  13. Regulating nutrient allocation in plants

    Science.gov (United States)

    Udvardi, Michael; Yang, Jiading; Worley, Eric

    2014-12-09

    The invention provides coding and promoter sequences for a VS-1 and AP-2 gene, which affects the developmental process of senescence in plants. Vectors, transgenic plants, seeds, and host cells comprising heterologous VS-1 and AP-2 genes are also provided. Additionally provided are methods of altering nutrient allocation and composition in a plant using the VS-1 and AP-2 genes.

  14. Operational risk economic capital allocation

    Science.gov (United States)

    Nikonov, Oleg I.; Vlasov, Vladimir E.; Medvedeva, Marina A.

    2013-10-01

    In the paper we describe a model of operational risk of economic capital estimation and allocation based on Loss Distribution Approach (LDA). Bank's total losses are modeled through Monte-Carlo simulations of its business units' losses. It allows to fairly distributing the corresponding capital between business units in order to assess and manage their risk adjusted performance.

  15. Planning and Resource Allocation Management.

    Science.gov (United States)

    Coleman, Jack W.

    1986-01-01

    Modern scientific management techniques provide college administrators with valuable planning and resource allocation insights and enhances the decision process. The planning model should incorporate assessment, strategic planning, dynamic and long-term budgeting, operational planning, and feedback and control for actual operations. (MSE)

  16. Designing for dynamic task allocation

    NARCIS (Netherlands)

    Dongen, C.J.G. van; Maanen, P.P. van

    2005-01-01

    Future platforms are envisioned in which human-machine teams are able to share and trade tasks as demands in situations change. It seems that human-machine coordination has not received the attention it deserves by past and present approaches to task allocation. In this paper a simple way to make

  17. Governance and Foreign Aid Allocation

    Science.gov (United States)

    2006-07-01

    In addition, this chapter develops a microeconomic model to explore donors’ aid allocation decisions and their potential impact on aid effectiveness...the promotion of market-based principles to restructure macroeconomic policies in developing countries. The greater focus on...be explained by successful development 29 efforts of number of countries in the region, such as Republic of Korea, Malaysia , Singapore, and Peoples

  18. Biomass supply chain management in North Carolina (part 2: biomass feedstock logistical optimization

    Directory of Open Access Journals (Sweden)

    Kevin Caffrey

    2016-03-01

    Full Text Available Biomass logistics operations account for a major portion of the feedstock cost of running a biorefinery, and make up a significant portion of total system operational costs. Biomass is a bulky perishable commodity that is required in large quantities year round for optimal biorefinery operations. As a proof of concept for a decision making tool for biomass production and delivery, a heuristic was developed to determine biorefinery location, considering city size, agricultural density, and regional demographics. Switchgrass and sorghum (with winter canola were selected to examine as viable biomass feedstocks based on positive economic results determined using a predictive model for cropland conversion potential. Biomass harvest systems were evaluated to examine interrelationships of biomass logistical networks and the least cost production system, with results demonstrating a need to shift to maximize supply-driven production harvest operations and limit storage requirements. For this supply-driven production harvest operations approach a harvest window from September until March was selected for producing big square bales of switchgrass for storage until use, forage chopped sorghum from September to December, and forage chopped switchgrass from December to March. A case study of the three major regions of North Carolina (Mountains, Piedmont, and Coastal Plain was used to assess logistical optimization of the proposed supply-driven production harvest system. Potential biomass production fields were determined within a hundred mile radius of the proposed biorefinery location, with individual fields designated for crop and harvest system by lowest transportation cost. From these selected fields, crops and harvest system regional storage locations were determined using an alternate location-allocation heuristic with set storage capacity per site. Model results showed that the supply-driven production harvest system greatly reduced system complexity

  19. Some effects of soil-moisture availability on above-ground production and reproductive allocation in Larrea tridentata (DC) Cov.

    Science.gov (United States)

    Cunningham, G L; Syvertsen, J P; Reynolds, J F; Willson, J M

    1979-01-01

    Data from the US/IBP Desert Biome validation studies indicate that above-ground production and biomass allocated to reproduction in Larrea tridentata vary from one year to another depending upon the timing and extent of soil-moisture availability. In an attempt to verify these observations and determine to what extent water availability can affect total aboveground production and reproductive allocation in this widely distributed warm desert shrub, a series of soil-moisture augmentation experiments were conducted. High levels of soil moisture had a greater effect on reproductive allocation than on total above-ground production. Enhanced soil moisture during the period of active growth increased total above-ground production and reduced the percentage of biomass allocated to reproduction. Enhanced soil moisture during the normal periods of little or no growth did not increase total above-ground production.

  20. Gasification of Woody Biomass.

    Science.gov (United States)

    Dai, Jianjun; Saayman, Jean; Grace, John R; Ellis, Naoko

    2015-01-01

    Interest in biomass to produce heat, power, liquid fuels, hydrogen, and value-added chemicals with reduced greenhouse gas emissions is increasing worldwide. Gasification is becoming a promising technology for biomass utilization with a positive environmental impact. This review focuses specifically on woody biomass gasification and recent advances in the field. The physical properties, chemical structure, and composition of biomass greatly affect gasification performance, pretreatment, and handling. Primary and secondary catalysts are of key importance to improve the conversion and cracking of tars, and lime-enhanced gasification advantageously combines CO2 capture with gasification. These topics are covered here, including the reaction mechanisms and biomass characterization. Experimental research and industrial experience are investigated to elucidate concepts, processes, and characteristics of woody biomass gasification and to identify challenges.

  1. Biomass to energy

    International Nuclear Information System (INIS)

    2006-06-01

    This road-map proposes by the Group Total aims to inform the public on the biomass to energy. It explains the biomass principle, the possibility of biomass to energy conversion, the first generation of biofuels (bio ethanol, ETBE, bio diesel, flex fuel) and their advantages and limitations, the european regulatory framework and policy with the evolutions and Total commitments in the domain. (A.L.B.)

  2. Terrestrial cycling of 13CO2 by photosynthesis, respiration, and biomass burning in SiBCASA

    Science.gov (United States)

    van der Velde, I. R.; Miller, J. B.; Schaefer, K.; van der Werf, G. R.; Krol, M. C.; Peters, W.

    2014-12-01

    We present an enhanced version of the SiBCASA terrestrial biosphere model that is extended with (a) biomass burning emissions from the SiBCASA carbon pools using remotely sensed burned area from the Global Fire Emissions Database (GFED), (b) an isotopic discrimination scheme that calculates 13C signatures of photosynthesis and autotrophic respiration, and (c) a separate set of 13C pools to carry isotope ratios into heterotrophic respiration. We quantify in this study the terrestrial exchange of CO2 and 13CO2 as a function of environmental changes in humidity and biomass burning. The implementation of biomass burning yields similar fluxes as CASA-GFED both in magnitude and spatial patterns. The implementation of isotope exchange gives a global mean discrimination value of 15.2‰, ranges between 4 and 20‰ depending on the photosynthetic pathway in the plant, and compares favorably (annually and seasonally) with other published values. Similarly, the isotopic disequilibrium is similar to other studies that include a small effect of biomass burning as it shortens the turnover of carbon. In comparison to measurements, a newly modified starch/sugar storage pool propagates the isotopic discrimination anomalies to respiration much better. In addition, the amplitude of the drought response by SiBCASA is lower than suggested by the measured isotope ratios. We show that a slight increase in the stomatal closure for large vapor pressure deficit would amplify the respired isotope ratio variability. Our study highlights the importance of isotope ratio observations of 13C to assess and improve biochemical models like SiBCASA, especially with regard to the allocation and turnover of carbon and the responses to drought.

  3. Prediction of Commuter’s Daily Time Allocation

    Directory of Open Access Journals (Sweden)

    Fang Zong

    2013-10-01

    Full Text Available This paper presents a model system to predict the time allocation in commuters’ daily activity-travel pattern. The departure time and the arrival time are estimated with Ordered Probit model and Support Vector Regression is introduced for travel time and activity duration prediction. Applied in a real-world time allocation prediction experiment, the model system shows a satisfactory level of prediction accuracy. This study provides useful insights into commuters’ activity-travel time allocation decision by identifying the important influences, and the results are readily applied to a wide range of transportation practice, such as travel information system, by providing reliable forecast for variations in travel demand over time. By introducing the Support Vector Regression, it also makes a methodological contribution in enhancing prediction accuracy of travel time and activity duration prediction.

  4. Process for treating biomass

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Timothy J.; Teymouri, Farzaneh

    2018-04-10

    This invention is directed to a process for treating biomass. The biomass is treated with a biomass swelling agent within the vessel to swell or rupture at least a portion of the biomass. A portion of the swelling agent is removed from a first end of the vessel following the treatment. Then steam is introduced into a second end of the vessel different from the first end to further remove swelling agent from the vessel in such a manner that the swelling agent exits the vessel at a relatively low water content.

  5. Process for treating biomass

    Science.gov (United States)

    Campbell, Timothy J.; Teymouri, Farzaneh

    2015-08-11

    This invention is directed to a process for treating biomass. The biomass is treated with a biomass swelling agent within the vessel to swell or rupture at least a portion of the biomass. A portion of the swelling agent is removed from a first end of the vessel following the treatment. Then steam is introduced into a second end of the vessel different from the first end to further remove swelling agent from the vessel in such a manner that the swelling agent exits the vessel at a relatively low water content.

  6. Energy production from biomass

    International Nuclear Information System (INIS)

    Bestebroer, S.I.

    1995-01-01

    The aim of the task group 'Energy Production from Biomass', initiated by the Dutch Ministry of Economic Affairs, was to identify bottlenecks in the development of biomass for energy production. The bottlenecks were identified by means of a process analysis of clean biomass fuels to the production of electricity and/or heat. The subjects in the process analysis are the potential availability of biomass, logistics, processing techniques, energy use, environmental effects, economic impact, and stimulation measures. Three categories of biomass are distinguished: organic residual matter, imported biomass, and energy crops, cultivated in the Netherlands. With regard to the processing techniques attention is paid to co-firing of clean biomass in existing electric power plants (co-firing in a coal-fired power plant or co-firing of fuel gas from biomass in a coal-fired or natural gas-fired power plant), and the combustion or gasification of clean biomass in special stand-alone installations. 5 figs., 13 tabs., 28 refs

  7. Biomass resources in California

    Energy Technology Data Exchange (ETDEWEB)

    Tiangco, V.M.; Sethi, P.S. [California Energy Commission, Sacramento, CA (United States)

    1993-12-31

    The biomass resources in California which have potential for energy conversion were assessed and characterized through the project funded by the California Energy Commission and the US Department of Energy`s Western Regional Biomass Energy Program (WRBEP). The results indicate that there is an abundance of biomass resources as yet untouched by the industry due to technical, economic, and environmental problems, and other barriers. These biomass resources include residues from field and seed crops, fruit and nut crops, vegetable crops, and nursery crops; food processing wastes; forest slash; energy crops; lumber mill waste; urban wood waste; urban yard waste; livestock manure; and chaparral. The estimated total potential of these biomass resource is approximately 47 million bone dry tons (BDT), which is equivalent to 780 billion MJ (740 trillion Btu). About 7 million BDT (132 billion MJ or 124 trillion Btu) of biomass residue was used for generating electricity by 66 direct combustion facilities with gross capacity of about 800 MW. This tonnage accounts for only about 15% of the total biomass resource potential identified in this study. The barriers interfering with the biomass utilization both in the on-site harvesting, collection, storage, handling, transportation, and conversion to energy are identified. The question whether these barriers present significant impact to biomass {open_quotes}availability{close_quotes} and {open_quotes}sustainability{close_quotes} remains to be answered.

  8. Carbon Allocation into Different Fine-Root Classes of Young Abies alba Trees Is Affected More by Phenology than by Simulated Browsing.

    Science.gov (United States)

    Endrulat, Tina; Buchmann, Nina; Brunner, Ivano

    2016-01-01

    Abies alba (European silver fir) was used to investigate possible effects of simulated browsing on C allocation belowground by 13CO2 pulse-labelling at spring, summer or autumn, and by harvesting the trees at the same time point of the labelling or at a later season for biomass and for 13C-allocation into the fine-root system. Before budburst in spring, the leader shoots and 50% of all lateral shoots of half of the investigated 5-year old Abies alba saplings were clipped to simulate browsing. At harvest, different fine-root classes were separated, and starch as an important storage compartment was analysed for concentrations. The phenology had a strong effect on the allocation of the 13C-label from shoots to roots. In spring, shoots did not supply the fine-roots with high amounts of the 13C-label, because the fine-roots contained less than 1% of the applied 13C. In summer and autumn, however, shoots allocated relatively high amounts of the 13C-label to the fine roots. The incorporation of the 13C-label as structural C or as starch into the roots is strongly dependent on the root type and the root diameter. In newly formed fine roots, 3-5% of the applied 13C was incorporated, whereas 1-3% in the ≤0.5 mm root class and 1-1.5% in the >0.5-1.0 mm root class were recorded. Highest 13C-enrichment in the starch was recorded in the newly formed fine roots in autumn. The clipping treatment had a significant positive effect on the amount of allocated 13C-label to the fine roots after the spring labelling, with high relative 13C-contents observed in the ≤0.5 mm and the >0.5-1.0 mm fine-root classes of clipped trees. No effects of the clipping were observed after summer and autumn labelling in the 13C-allocation patterns. Overall, our data imply that the season of C assimilation and, thus, the phenology of trees is the main determinant of the C allocation from shoots to roots and is clearly more important than browsing.

  9. Productivity and carbon allocation in pure and mixed-species plantations of Eucalyptus grandis and Acacia mangium in Brazil

    Science.gov (United States)

    Nouvellon, Y.; Laclau, J.; Epron, D.; Le Maire, G.; Gonçalves, J.; Bouillet, J.

    2010-12-01

    Nitrogen fertilizer inputs are required in fast growing eucalypt plantations to meet tree requirements, and to compensate for the large nitrogen outputs associated with wood exportation at the end of the short rotations. Due to the economic and potential environmental cost of fertilizers, mixed-species plantations (MSP) with N-fixing species (NFS) such as Acacia sp. might be an attractive option to improve the long-term soil N (and possibly soil carbon) status. In such MSP, increases in N availability may influence the productivity and C partitioning of the non-N fixing species. To investigate the effects of NFS on nutrient cycling, wood production, C sequestration, and soil fertility, a randomized block design including monocultures of Eucalyptus grandis (100%E) and Acacia mangium (100%A), and mixtures of these species (50%E:50%A) was set up in southern Brazil. Our specific goals in the present study were to compare the production and C allocation patterns of these plantations, during the two last years of the 6-yr rotation. We hypothesized that 1) a large part of the differences in wood production between monospecific stands would be explained by differences in C allocation; and 2) the C allocation patterns of each species would be strongly modified in mixed- species plantations compared to mono-specific plantations due to inter-specific interactions and shifts in soil N status. Biomass increase (growth, G) in the different plant compartments was assessed by means of inventories and allometric relationships. Total aboveground net primary productivity (ANPP), and the productivity of each aboveground plant compartment were estimated from measurements of G and litterfall (L) (ANPP=G+L). Total belowground C allocations (TBCA) were estimated using a mass-balance approach as soil CO2 efflux C minus the C input from aboveground litter plus changes in the C stored in roots, in the forest floor litter layer, and in soil. Over this first rotation, mixing NFS with eucalypt

  10. In Search of Gender Bias in Household Resource Allocation in Rural China

    OpenAIRE

    Song, Lina

    2008-01-01

    This paper tests three hypotheses concerning intra-household resource allocation in rural China. First, whether increasing the women's bargaining power alters household expenditure patterns. Second, whether households allocate fewer resources to daughters than to sons. Third, whether increasing the bargaining power of women reduces pro-boy discrimination. We find that expenditure patterns do vary with proxies for women's bargaining power. Pro-boy discrimination is suggested by: lower female o...

  11. Allocation plasticity and plant-metal partitioning: Meta-analytical perspectives in phytoremediation

    International Nuclear Information System (INIS)

    Audet, Patrick; Charest, Christiane

    2008-01-01

    In this meta-analysis of plant growth and metal uptake parameters, we selected 19 studies of heavy metal (HM) phytoremediation to evaluate trends of allocation plasticity and plant-metal partitioning in roots relative to shoots. We calculated indexes of biomass allocation and metal distribution for numerous metals and plant species among four families of interest for phytoremediation purposes (e.g. Brassicaceae, Fabaceae, Poaceae, and Solanaceae). We determined that plants shift their biomass and distribute metals more to roots than shoots possibly to circumvent the challenges of increasing soil-HM conditions. Although this shift is viewed as a stress-avoidance strategy complementing intrinsic stress-tolerance, our findings indicate that plants express different levels of allocation plasticity and metal partitioning depending on their overall growth strategy and status as 'fast-grower' or 'slow-grower' species. Accordingly, we propose a conceptual model of allocation plasticity and plant-metal partitioning comparing 'fast-grower' and 'slow-grower' strategies and outlining applications for remediation practices. - This meta-analysis has revealed a shift in plant biomass and metal distribution from shoots to roots possibly to protect vital functions when subjected to metal stress

  12. Allocation plasticity and plant-metal partitioning: Meta-analytical perspectives in phytoremediation

    Energy Technology Data Exchange (ETDEWEB)

    Audet, Patrick [Ottawa-Carleton Institute of Biology, Department of Biology, University of Ottawa, 30 Marie-Curie Street, Ottawa, ON K1N 6N5 (Canada)], E-mail: paude086@uottawa.ca; Charest, Christiane [Ottawa-Carleton Institute of Biology, Department of Biology, University of Ottawa, 30 Marie-Curie Street, Ottawa, ON K1N 6N5 (Canada)], E-mail: ccharest@uottawa.ca

    2008-11-15

    In this meta-analysis of plant growth and metal uptake parameters, we selected 19 studies of heavy metal (HM) phytoremediation to evaluate trends of allocation plasticity and plant-metal partitioning in roots relative to shoots. We calculated indexes of biomass allocation and metal distribution for numerous metals and plant species among four families of interest for phytoremediation purposes (e.g. Brassicaceae, Fabaceae, Poaceae, and Solanaceae). We determined that plants shift their biomass and distribute metals more to roots than shoots possibly to circumvent the challenges of increasing soil-HM conditions. Although this shift is viewed as a stress-avoidance strategy complementing intrinsic stress-tolerance, our findings indicate that plants express different levels of allocation plasticity and metal partitioning depending on their overall growth strategy and status as 'fast-grower' or 'slow-grower' species. Accordingly, we propose a conceptual model of allocation plasticity and plant-metal partitioning comparing 'fast-grower' and 'slow-grower' strategies and outlining applications for remediation practices. - This meta-analysis has revealed a shift in plant biomass and metal distribution from shoots to roots possibly to protect vital functions when subjected to metal stress.

  13. Mycorrhizal Enhancement of Biomass Productivity of Big Bluestem ...

    African Journals Online (AJOL)

    The usual biomass partitioning by BB at pH=4.5 deserves further investigation. Different patterns of biomass partitioning notwithstanding, results of this study strongly suggest that BB could complement SG, the model biofuel feedstock, especially under acidic substrate conditions. Key words: Big bluestem; switchgrass; ...

  14. Vegetation biomass prediction in the cattle corridor of Uganda ...

    African Journals Online (AJOL)

    production under the 2071-2100 projected rainfall conditions. Spatio-temporal pattern of vegetative biomass production were determined by analysis of the seasonal variation of Normalised Difference Vegetation Index (NDVI) for 10 years from 2001-2010. A biomass relationship was established between the NDVI and the ...

  15. Biomass burning losses of carbon estimated from ecosystem modeling and satellite data analysis for the Brazilian Amazon region

    Science.gov (United States)

    Potter, Christopher; Brooks Genovese, Vanessa; Klooster, Steven; Bobo, Matthew; Torregrosa, Alicia

    To produce a new daily record of gross carbon emissions from biomass burning events and post-burning decomposition fluxes in the states of the Brazilian Legal Amazon (Instituto Brasileiro de Geografia e Estatistica (IBGE), 1991. Anuario Estatistico do Brasil, Vol. 51. Rio de Janeiro, Brazil pp. 1-1024). We have used vegetation greenness estimates from satellite images as inputs to a terrestrial ecosystem production model. This carbon allocation model generates new estimates of regional aboveground vegetation biomass at 8-km resolution. The modeled biomass product is then combined for the first time with fire pixel counts from the advanced very high-resolution radiometer (AVHRR) to overlay regional burning activities in the Amazon. Results from our analysis indicate that carbon emission estimates from annual region-wide sources of deforestation and biomass burning in the early 1990s are apparently three to five times higher than reported in previous studies for the Brazilian Legal Amazon (Houghton et al., 2000. Nature 403, 301-304; Fearnside, 1997. Climatic Change 35, 321-360), i.e., studies which implied that the Legal Amazon region tends toward a net-zero annual source of terrestrial carbon. In contrast, our analysis implies that the total source fluxes over the entire Legal Amazon region range from 0.2 to 1.2 Pg C yr -1, depending strongly on annual rainfall patterns. The reasons for our higher burning emission estimates are (1) use of combustion fractions typically measured during Amazon forest burning events for computing carbon losses, (2) more detailed geographic distribution of vegetation biomass and daily fire activity for the region, and (3) inclusion of fire effects in extensive areas of the Legal Amazon covered by open woodland, secondary forests, savanna, and pasture vegetation. The total area of rainforest estimated annually to be deforested did not differ substantially among the previous analyses cited and our own.

  16. Integer Programming Models for Sales Resource Allocation

    OpenAIRE

    Andris A. Zoltners; Prabhakant Sinha

    1980-01-01

    A practical conceptual framework for sales resource allocation modeling is presented in this paper. A literature review of sales resource allocation models is described in terms of this framework. The conceptual framework also lends itself to several integer programming models which may be used to address the variety of sales resource allocation decisions faced by every sales organization. A general model for sales resource allocation is developed which incorporates multiple sales resources, ...

  17. Hydrothermal conversion of biomass

    NARCIS (Netherlands)

    Knezevic, D.

    2009-01-01

    This thesis presents research of hydrothermal conversion of biomass (HTC). In this process, hot compressed water (subcritical water) is used as the reaction medium. Therefore this technique is suitable for conversion of wet biomass/ waste streams. By working at high pressures, the evaporation of

  18. World wide biomass resources

    NARCIS (Netherlands)

    Faaij, A.P.C.

    2012-01-01

    In a wide variety of scenarios, policy strategies, and studies that address the future world energy demand and the reduction of greenhouse gas emissions, biomass is considered to play a major role as renewable energy carrier. Over the past decades, the modern use of biomass has increased

  19. Energetische Verwertung von Biomasse

    Science.gov (United States)

    Zahoransky, Richard; Allelein, Hans-Josef; Bollin, Elmar; Oehler, Helmut; Schelling, Udo

    Etwa 0,1% der Solarenergie wandeln sich durch Photosynthese aus dem Kohlendioxid der Luft in Biomasse um. Die Biomassen sind als Festbrennstoff nutzbar oder zu gasförmigen Brennstoffen weiterverarbeitbar. Zwei Arten von Biomassen sind zu unterscheiden: Anfallende Biomasse

  20. Air quality on biomass harvesting operations

    Science.gov (United States)

    Dana Mitchell

    2011-01-01

    The working environment around logging operations can be very dusty. But, air quality around logging operations is not well documented. Equipment movements and trafficking on the landing can cause dust to rise into the air. The addition of a biomass chipper creates different air flow patterns and may stir up additional dust. This project addresses two topics related to...

  1. Integrating spatial and biomass planning for the United States

    International Nuclear Information System (INIS)

    Wang, Sicong; Wang, Shifeng

    2016-01-01

    Biomass is low-carbon energy and has tremendous potential as an alternative to fossil fuels. However, the significant role of biomass in future low-carbon energy portfolio depends heavily on its consumption. The paper presents a first attempt to examine the spatial-temporal patterns of biomass consumption in the United States (US), using a novel method-spatial Seemingly Unrelated Regression (SUR) model, in order to strengthen the link between energy planning and spatial planning. In order to obtain the robust parameters of spatial SUR models and estimate the parameters efficiently, an iterative maximum likelihood method, which takes full advantage of the stationary characteristic of maximum likelihood estimation, has been developed. The robust parameters of models can help draw a proper inference for biomass consumption. Then the spatial-temporal patterns of biomass consumption in the US at the state level are investigated using the spatial SUR models with the estimation method developed and data covering the period of 2000–2012. Results show that there are spatial dependences among biomass consumption. The presence of spatial dependence in biomass consumption has informative implications for making sustainable biomass polices. It suggests new efforts to adding a cross-state dimension to state-level energy policy and coordinating some elements of energy policy across states are still needed. In addition, results consistent with classic economic theory further proves the correctness of applying the spatial SUR models to investigate the spatial-temporal patterns of biomass consumption. - Highlights: • A spatial model is suggested as framework to investigate biomass consumption. • A new estimation method is developed to obtain the robust parameters of model. • There are spatial dependences among biomass consumption. • The spatial dependence can contribute to making sustainable biomass policies. • Efforts to adding cross-state dimension to state

  2. Intelligent tactical asset allocation support system

    NARCIS (Netherlands)

    Hiemstra, Y.

    1995-01-01

    This paper presents an advanced support system for Tactical Asset Allocation. Asset allocation explains over 90% of portfolio performance (Brinson, Hood and Beebower, 1988). Tactical asset allocation adjusts a strategic portfolio on the basis of short term market outlooks. The system includes

  3. Hydrothermal liquefaction of biomass

    DEFF Research Database (Denmark)

    Toor, Saqib; Rosendahl, Lasse; Rudolf, Andreas

    2011-01-01

    This article reviews the hydrothermal liquefaction of biomass with the aim of describing the current status of the technology. Hydrothermal liquefaction is a medium-temperature, high-pressure thermochemical process, which produces a liquid product, often called bio-oil or bi-crude. During...... the hydrothermal liquefaction process, the macromolecules of the biomass are first hydrolyzed and/or degraded into smaller molecules. Many of the produced molecules are unstable and reactive and can recombine into larger ones. During this process, a substantial part of the oxygen in the biomass is removed...... by dehydration or decarboxylation. The chemical properties of bio-oil are highly dependent of the biomass substrate composition. Biomass constitutes of various components such as protein; carbohydrates, lignin and fat, and each of them produce distinct spectra of compounds during hydrothermal liquefaction...

  4. Biomass burning in India

    International Nuclear Information System (INIS)

    Joshi, V.

    1991-01-01

    This chapter summarizes the direct biomass burning practices in India. The review pertains to fire practices in forest, agricultural fields, grasslands, households, and industry. In forest land, extent of controlled burning for regeneration and fire prevention is estimated based on the forest statistics. The biomass burned annually due to accidental fires and for shifting cultivation is quantified based on a few earlier studies. In the case of household and small-scale industries, the biomass burned is quantified by extrapolating past data on energy consumption. In addition to wood and crop residues, the use of dungcakes and charcoal is also accounted for in calculating the total amount of biofuels burned annually. Wherever possible, regional and seasonal variations in the biomass burning practices are highlighted. This exercise has led to improve the current estimates of biomass burned annually in India. The factors influencing the impact of National Programme on Improved Cookstoves (NPIC) in reducing the greenhouse gas emissions are discussed

  5. Rheology of concentrated biomass

    Science.gov (United States)

    Samaniuk, J. R.; Wang, J.; Root, T. W.; Scott, C. T.; Klingenberg, D. J.

    2011-12-01

    Economic processing of lignocellulosic biomass requires handling the biomass at high solids concentration. This creates challenges because concentrated biomass behaves as a Bingham-like material with large yield stresses. Here we employ torque rheometry to measure the rheological properties of concentrated lignocellulosic biomass (corn stover). Yield stresses obtained using torque rheometry agree with those obtained using other rheometric methods, but torque rheometry can be used at much larger solids concentration (weight fractions of insoluble solids greater than 0.2). Yield stresses decrease with severity of hydrolysis, decrease when water-soluble polymers are added (for nonhydrolyzed biomass), and increase with particle length. Experimental results are qualitatively consistent with those obtained from particle-level simulations.

  6. Remarks on energetic biomass

    International Nuclear Information System (INIS)

    Mathis, Paul; Pelletier, Georges

    2011-01-01

    The authors report a study of energy biomass by considering its three main sources (forest, agriculture and wastes) and three energy needs (heat, fuel for transports, electricity) in the French national context. After having recalled the various uses of biomass (animal feeding, energy production, materials, chemical products), the authors discuss the characteristics of biomass with respect to other energy sources. Then, they analyse and discuss the various energy needs which biomass could satisfy: heat production (in industry, in the residential and office building sector), fuel for transports, electricity production. They assess and discuss the possible biomass production of its three main sources: forest, agriculture, and wastes (household, agricultural and industrial wastes). They also discuss the opportunities for biogas production and for second generation bio-fuel production

  7. Release of resource constraints allows greater carbon allocation to secondary metabolites and storage in winter wheat.

    Science.gov (United States)

    Huang, Jianbei; Hammerbacher, Almuth; Forkelová, Lenka; Hartmann, Henrik

    2017-05-01

    The atmospheric CO 2 concentration ([CO 2 ]) is rapidly increasing, and this may have substantial impact on how plants allocate metabolic resources. A thorough understanding of allocation priorities can be achieved by modifying [CO 2 ] over a large gradient, including low [CO 2 ], thereby altering plant carbon (C) availability. Such information is of critical importance for understanding plant responses to global environmental change. We quantified the percentage of daytime whole-plant net assimilation (A) allocated to night-time respiration (R), structural growth (SG), nonstructural carbohydrates (NSC) and secondary metabolites (SMs) during 8 weeks of vegetative growth in winter wheat (Triticum aestivum) growing at low, ambient and elevated [CO 2 ] (170, 390 and 680 ppm). R/A remained relatively constant over a large gradient of [CO 2 ]. However, with increasing C availability, the fraction of assimilation allocated to biomass (SG + NSC + SMs), in particular NSC and SMs, increased. At low [CO 2 ], biomass and NSC increased in leaves but decreased in stems and roots, which may help plants achieve a functional equilibrium, that is, overcome the most severe resource limitation. These results reveal that increasing C availability from rising [CO 2 ] releases allocation constraints, thereby allowing greater investment into long-term survival in the form of NSC and SMs. © 2016 John Wiley & Sons Ltd.

  8. Towards an understanding of the molecular regulation of carbon allocation in diatoms: the interaction of energy and carbon allocation.

    Science.gov (United States)

    Wagner, Heiko; Jakob, Torsten; Fanesi, Andrea; Wilhelm, Christian

    2017-09-05

    In microalgae, the photosynthesis-driven CO 2 assimilation delivers cell building blocks that are used in different biosynthetic pathways. Little is known about how the cell regulates the subsequent carbon allocation to, for example, cell growth or for storage. However, knowledge about these regulatory mechanisms is of high biotechnological and ecological importance. In diatoms, the situation becomes even more complex because, as a consequence of their secondary endosymbiotic origin, the compartmentation of the pathways for the primary metabolic routes is different from green algae. Therefore, the mechanisms to manipulate the carbon allocation pattern cannot be adopted from the green lineage. This review describes the general pathways of cellular energy distribution from light absorption towards the final allocation of carbon into macromolecules and summarizes the current knowledge of diatom-specific allocation patterns. We further describe the (limited) knowledge of regulatory mechanisms of carbon partitioning between lipids, carbohydrates and proteins in diatoms. We present solutions to overcome the problems that hinder the identification of regulatory elements of carbon metabolism.This article is part of the themed issue 'The peculiar carbon metabolism in diatoms'. © 2017 The Author(s).

  9. Cost Allocation and Convex Data Envelopment

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tind, Jørgen

    This paper considers allocation rules. First, we demonstrate that costs allocated by the Aumann-Shapley and the Friedman-Moulin cost allocation rules are easy to determine in practice using convex envelopment of registered cost data and parametric programming. Second, from the linear programming...... such as Data Envelopment Analysis (DEA). The convexity constraint of the BCC model introduces a non-zero slack in the objective function of the multiplier problem and we show that the cost allocation rules discussed in this paper can be used as candidates to allocate this slack value on to the input (or output...

  10. Biomass CHP Catalog of Technologies

    Science.gov (United States)

    This report reviews the technical and economic characterization of biomass resources, biomass preparation, energy conversion technologies, power production systems, and complete integrated CHP systems.

  11. The potential biomass for energy production in the Czech Republic

    International Nuclear Information System (INIS)

    Lewandowski, I.; van Hooijdonk, A.; van Dam, J.; Faaij, A.; Weger, J.; Havlickova, K.

    2006-01-01

    Biomass production is a promising alternative for the Czech Republic's (CZ) agricultural sector. Biomass could cover the domestic bio-energy demand of 250PJa -1 (predicted for 2030), and could be exported as bio-fuels to other EU countries. This study assesses the CZ's biomass production potential on a regional level and provides cost-supply curves for biomass from energy crops and agricultural and forestry residues. Agricultural productivity and the amount of land available for energy crop production are key variables in determining biomass potentials. Six scenarios for 2030 with different crop-yield levels, feed conversion efficiencies and land allocation procedures were built. The demand for food and fodder production was derived from FAO predictions for 2030. Biomass potential in the CZ is mainly determined by the development of food and fodder crop yields because the amount of land available for energy crop production increases with increasing productivity of food and fodder crops. In most scenarios the NUTS-3 regions CZ020, 31 and 32 provided the most land for energy-crop production and the highest biomass potentials. About 110PJa -1 , mostly from agricultural and forestry residues, can be provided from biomass when the present Czech agricultural productivity is maintained. About 195PJa -1 (105PJ from energy crops) can be provided when production systems are optimised with regard to fertilizer regimes and 365PJa -1 (290PJ from energy crops) when the yield level of Dutch agriculture is reached. Costs for woody biomass decrease with increasing plantation yield and range between 2.58 and 4.76 GJ -1 . It was concluded that Czech agriculture could provide enough biomass for domestic demand and for export if agricultural productivity is increased. (author)

  12. The biomass file

    International Nuclear Information System (INIS)

    2010-01-01

    As biomass represents the main source of renewable energy to reach the 23 per cent objective in terms of energy consumption by 2020, a first article gives a synthetic overview of its definition, its origins, its possible uses, its share in the French energy mix, its role by 2020, strengths and weaknesses for its development, the growth potential of its market, and its implications in terms of employment. A second article outlines the assets of biomass, indicates the share of some crops in biomass energy production, and discusses the development of new resources and the possible energy valorisation of various by-products. Interviews about biomass market and development perspectives are proposed with representatives of institutions, energy industries and professional bodies concerned with biomass development and production. Other articles comments the slow development of biomass-based cogeneration, the coming into operation of a demonstration biomass roasting installation in Pau (France), the development potential of biogas in France, the project of bio natural gas vehicles in Lille, and the large development of biogas in Germany

  13. Modeling of biomass pyrolysis

    International Nuclear Information System (INIS)

    Samo, S.R.; Memon, A.S.; Akhund, M.A.

    1995-01-01

    The fuels used in industry and power sector for the last two decades have become expensive. As a result renewable energy source have been emerging increasingly important, of these, biomass appears to be the most applicable in the near future. The pyrolysis of biomass plays a key role amongst the three major and important process generally encountered in a gas producer, namely, pyrolysis, combustion and reduction of combustion products. Each biomass has its own pyrolysis characteristics and this important parameters must be known for the proper design and efficient operation of a gasification system. Thermogravimetric analysis has been widely used to study the devolatilization of solid fuels, such as biomass. It provides the weight loss history of a sample heated at a predetermined rate as a function of time and temperature. This paper presents the experimental results of modelling the weight loss curves of the main biomass components i.e. cellulose, hemicellulose and lignin. Thermogravimetric analysis of main components of biomass showed that pyrolysis is first order reaction. Furthermore pyrolysis of cellulose and hemicelluloe can be regarded as taking place in two stages, for while lignin pyrolysis is a single stage process. This paper also describes the Thermogravimetric Analysis (TGA) technique to predict the weight retained during pyrolysis at any temperature, for number of biomass species, such as cotton stalk, bagasse ad graoundnut shell. (author)

  14. Cost allocation review : staff discussion paper

    International Nuclear Information System (INIS)

    2005-09-01

    This report addressed the need for updated cost allocation studies filed by local electricity distribution companies because they ensure that distribution rates for each customer class remain just and reasonable. According to the 2001 Electricity Distribution Rate Handbook, the Ontario Energy Board requires new cost allocation studies before implementing any future incentive regulation plans. A review of cost allocations allows the Board to consider the need for adjustments to the current share of distribution costs paid by different classes of ratepayers. This report included 14 sections to facilitate consultations with stakeholders on financial information requirements for cost allocation; directly assignable costs; functionalization; categorization; allocation methods; allocation of other costs; load data requirements; cost allocation implementation issues; addition of new rate class and rate design for scattered unmetered loads; addition of new rate class for larger users; rates to charge embedded distributors; treatment of the rate sub-classification identified as time-of-use; and, rate design implementation issues. 1 fig., 7 appendices

  15. Electricity from biomass

    International Nuclear Information System (INIS)

    Price, B.

    1998-11-01

    Electricity from biomass assesses the potential of biomass electricity for displacing other more polluting power sources and providing a relatively clean and ecologically friendly source of energy; discusses its environmental and economic effects, while analysing political and institutional initiatives and constraints; evaluates key factors, such as energy efficiency, economics, decentralisation and political repurcussions; considers the processes and technologies employed to produce electricity from biomass; and discusses the full range of incentives offered to producers and potential producers and the far-reaching implications it could have for industry, society and the environment. (author)

  16. Biomass in Germany

    International Nuclear Information System (INIS)

    Chapron, Thibaut

    2014-01-01

    This document provides, first, an overview of biomass industry in Germany: energy consumption and renewable energy production, the French and German electricity mix, the 2003-2013 evolution of renewable electricity production and the 2020 forecasts, the biomass power plants, plantations, biofuels production and consumption in Germany. Then, the legal framework of biofuels development in Germany is addressed (financial incentives, tariffs, direct electricity selling). Next, a focus is made on biogas production both in France and in Germany (facilities, resources). Finally, the French-German cooperation in the biomass industry and the research actors are presented

  17. Biomass_Master

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Biomass data found in this data set are broken into four regions of the Northeast US Continental Shelf Large Marine Ecosystem: Gulf of Maine, Georges Bank,...

  18. Hydrothermal liquefaction of biomass

    DEFF Research Database (Denmark)

    Toor, Saqib; Rosendahl, Lasse; Hoffmann, Jessica

    2014-01-01

    Biomass is one of the most abundant sources of renewable energy, and will be an important part of a more sustainable future energy system. In addition to direct combustion, there is growing attention on conversion of biomass into liquid en-ergy carriers. These conversion methods are divided...... into biochemical/biotechnical methods and thermochemical methods; such as direct combustion, pyrolysis, gasification, liquefaction etc. This chapter will focus on hydrothermal liquefaction, where high pressures and intermediate temperatures together with the presence of water are used to convert biomass...... into liquid biofuels, with the aim of describing the current status and development challenges of the technology. During the hydrothermal liquefaction process, the biomass macromolecules are first hydrolyzed and/or degraded into smaller molecules. Many of the produced molecules are unstable and reactive...

  19. Biomass: a growing role

    International Nuclear Information System (INIS)

    Junginger, M.; Faaij, A.; Rosillo-Calle, F.; Woods, J.

    2006-01-01

    In 2006, an article in the journal Renewable Energy World discussed the sustainability of biofuels, their potential to contribute to the global energy demand, reduction of greenhouse gas emissions, and their impact on biodiversity and land use. The essence of the present paper is to contribute to the aforesaid discussion under the sub-headings of (a) biomass production potentials and the importance of technological development and crops to satisfy this potential; (b) critical aspects for the development of biomass on a large scale for energy production; (c) overview of current developments to ensure the environmentally-friendliness of biomass through the development of safeguards and (d) sustainable international bioenergy trade as a driver to develop the potential of biomass. (author)

  20. 2007 Biomass Program Overview

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2009-10-27

    The Biomass Program is actively working with public and private partners to meet production and technology needs. With the corn ethanol market growing steadily, researchers are unlocking the potential of non-food biomass sources, such as switchgrass and forest and agricultural residues. In this way, the Program is helping to ensure that cost-effective technologies will be ready to support production goals for advanced biofuels.

  1. Light and nutrient effects on growth and allocation of Inga vera(Leguminosae), a successional tree of Puerto Rico.

    Science.gov (United States)

    R. W. Myster

    2006-01-01

    With the aim of acquiring a better understanding of ecological growth and biomass allocation of Neotropical trees, I inoculated Inga vera Willd. (Leguminosae) plants from cuttings with Rhizobium spp. and arbuscular mycorrhizal fungi and grew them in a greenhouse for 8 months under varying light (L), phosphorus (P), and nitrogen (N) treatments. I obtained the following...

  2. Utilization of the biomass in Japan: state of the researches and involvement of the enterprises; Utilisation de la biomasse au Japon: etat des recherches et implication des entreprises

    Energy Technology Data Exchange (ETDEWEB)

    Gabet, A.

    2003-09-01

    Following the Kyoto demands the budgets allocated to the renewable energies researches are more and more important. Among these energies the biomass is very popular in Japan because it does not increase the carbon dioxide level in the atmosphere. Since the years 1990 the Japan implemented three ministries to promote the biomass energy in the country. This document presents the biomass situation in the world and more specially in the Japan and the researches programs with the NEDO, the New Energy and Industrial Technology Development Organization). (A.L.B.)

  3. Biomass feedstock analyses

    Energy Technology Data Exchange (ETDEWEB)

    Wilen, C.; Moilanen, A.; Kurkela, E. [VTT Energy, Espoo (Finland). Energy Production Technologies

    1996-12-31

    The overall objectives of the project `Feasibility of electricity production from biomass by pressurized gasification systems` within the EC Research Programme JOULE II were to evaluate the potential of advanced power production systems based on biomass gasification and to study the technical and economic feasibility of these new processes with different type of biomass feed stocks. This report was prepared as part of this R and D project. The objectives of this task were to perform fuel analyses of potential woody and herbaceous biomasses with specific regard to the gasification properties of the selected feed stocks. The analyses of 15 Scandinavian and European biomass feed stock included density, proximate and ultimate analyses, trace compounds, ash composition and fusion behaviour in oxidizing and reducing atmospheres. The wood-derived fuels, such as whole-tree chips, forest residues, bark and to some extent willow, can be expected to have good gasification properties. Difficulties caused by ash fusion and sintering in straw combustion and gasification are generally known. The ash and alkali metal contents of the European biomasses harvested in Italy resembled those of the Nordic straws, and it is expected that they behave to a great extent as straw in gasification. Any direct relation between the ash fusion behavior (determined according to the standard method) and, for instance, the alkali metal content was not found in the laboratory determinations. A more profound characterisation of the fuels would require gasification experiments in a thermobalance and a PDU (Process development Unit) rig. (orig.) (10 refs.)

  4. Solid biomass barometer

    International Nuclear Information System (INIS)

    Anon.

    2011-01-01

    The primary energy production from solid biomass in the European Union reached 79.3 Mtoe in 2010 which implies a growth rate of 8% between 2009 and 2010. The trend, which was driven deeper by Europe's particularly cold winter of 2009-2010, demonstrates that the economic down-turn failed to weaken the member states' efforts to structure the solid biomass sector. Heat consumption rose sharply: the volume of heat sold by heating networks increased by 18% and reached 6.7 Mtoe and if we consider the total heat consumption (it means with and without recovery via heating networks) the figure is 66 Mtoe in 2010, which amounts to 10.1% growth. The growth of electricity production continued through 2010 (8.3% up on 2009) and rose to 67 TWh but at a slower pace than in 2009 (when it rose by 11.3% on 2008). The situation of the main producer countries: Sweden, Finland, Germany and France is reviewed. It appears that cogeneration unit manufacturers and biomass power plant constructors are the main beneficiaries of the current biomass energy sector boom. There is a trend to replace coal-fired plants that are either obsolete or near their end of life with biomass or multi-fuel plants. These opportunities will enable the industry to develop and further exploit new technologies such as gasification, pyrolysis and torrefaction which will enable biomass to be turned into bio-coal. (A.C.)

  5. Northeast Regional Biomass Program

    Energy Technology Data Exchange (ETDEWEB)

    Lusk, P.D.

    1992-12-01

    The Northeast Regional Biomass Program has been in operation for a period of nine years. During this time, state managed programs and technical programs have been conducted covering a wide range of activities primarily aim at the use and applications of wood as a fuel. These activities include: assessments of available biomass resources; surveys to determine what industries, businesses, institutions, and utility companies use wood and wood waste for fuel; and workshops, seminars, and demonstrations to provide technical assistance. In the Northeast, an estimated 6.2 million tons of wood are used in the commercial and industrial sector, where 12.5 million cords are used for residential heating annually. Of this useage, 1504.7 mw of power has been generated from biomass. The use of wood energy products has had substantial employment and income benefits in the region. Although wood and woodwaste have received primary emphasis in the regional program, the use of municipal solid waste has received increased emphasis as an energy source. The energy contribution of biomass will increase as potentia users become more familiar with existing feedstocks, technologies, and applications. The Northeast Regional Biomass Program is designed to support region-specific to overcome near-term barriers to biomass energy use.

  6. Transmission usage cost allocation schemes

    International Nuclear Information System (INIS)

    Abou El Ela, A.A.; El-Sehiemy, R.A.

    2009-01-01

    This paper presents different suggested transmission usage cost allocation (TCA) schemes to the system individuals. Different independent system operator (ISO) visions are presented using the proportional rata and flow-based TCA methods. There are two proposed flow-based TCA schemes (FTCA). The first FTCA scheme generalizes the equivalent bilateral exchanges (EBE) concepts for lossy networks through two-stage procedure. The second FTCA scheme is based on the modified sensitivity factors (MSF). These factors are developed from the actual measurements of power flows in transmission lines and the power injections at different buses. The proposed schemes exhibit desirable apportioning properties and are easy to implement and understand. Case studies for different loading conditions are carried out to show the capability of the proposed schemes for solving the TCA problem. (author)

  7. Legitimate Allocation of Public Healthcare

    DEFF Research Database (Denmark)

    Lippert-Rasmussen, Kasper; Lauridsen, Sigurd

    2009-01-01

    Citizens' consent to political decisions is often regarded as a necessary condition of political legitimacy. Consequently, legitimate allocation of healthcare has seemed almost unattainable in contemporary pluralistic societies. The problem is that citizens do not agree on any single principle...... governing priorities among groups of patients. The Accountability for Reasonableness (A4R) framework suggests an ingenious solution to this problem of moral disagreement. Rather than advocating any substantive distributive principle, its advocates propose a feasible set of conditions, which, if met...... by decision makers at the institutional level, provide, so it is promised, legitimate decisions. While we agree that A4R represents an important contribution to the priority-setting debate, we challenge the framework in two respects. First, we argue that A4R, and more specifically the relevance condition of A...

  8. Theory of stable allocations II

    Directory of Open Access Journals (Sweden)

    Pantelić Svetlana

    2015-01-01

    Full Text Available The Swedish Royal Academy awarded the 2012 Nobel Prize in Economics to Lloyd Shapley and Alvin Roth, for the theory of stable allocations and the practice of market design. These two American researchers worked independently from each other, combining basic theory and empirical investigations. Through their experiments and practical design they generated a flourishing field of research and improved the performance of many markets. Shapley provided the fundamental theoretical contribution to this field of research, whereas Roth, a professor at the Harvard University in Boston, developed and upgraded these theoretical investigations by applying them to the American market of medical doctors. Namely, their research helps explain the market processes at work, for instance, when doctors are assigned to hospitals, students to schools and human organs for transplant to recipients.

  9. Biomass cogeneration. A business assessment

    Energy Technology Data Exchange (ETDEWEB)

    Skelton, J.C.

    1981-11-01

    This guide serves as an overview of the biomass cogeneration area and provides direction for more detailed analysis. The business assessment is based in part on discussions with key officials from firms that have adopted biomass cogeneration systems and from organizations such as utilities, state and federal agencies, and banks that would be directly involved in a biomass cogeneration project. The guide is organized into five chapters: biomass cogeneration systems, biomass cogeneration business considerations, biomass cogeneration economics, biomass cogeneration project planning, and case studies.

  10. Cognitive radio networks dynamic resource allocation schemes

    CERN Document Server

    Wang, Shaowei

    2014-01-01

    This SpringerBrief presents a survey of dynamic resource allocation schemes in Cognitive Radio (CR) Systems, focusing on the spectral-efficiency and energy-efficiency in wireless networks. It also introduces a variety of dynamic resource allocation schemes for CR networks and provides a concise introduction of the landscape of CR technology. The author covers in detail the dynamic resource allocation problem for the motivations and challenges in CR systems. The Spectral- and Energy-Efficient resource allocation schemes are comprehensively investigated, including new insights into the trade-off

  11. Immunological Approaches to Biomass Characterization and Utilization.

    Science.gov (United States)

    Pattathil, Sivakumar; Avci, Utku; Zhang, Tiantian; Cardenas, Claudia L; Hahn, Michael G

    2015-01-01

    Plant biomass is the major renewable feedstock resource for sustainable generation of alternative transportation fuels to replace fossil carbon-derived fuels. Lignocellulosic cell walls are the principal component of plant biomass. Hence, a detailed understanding of plant cell wall structure and biosynthesis is an important aspect of bioenergy research. Cell walls are dynamic in their composition and structure, varying considerably among different organs, cells, and developmental stages of plants. Hence, tools are needed that are highly efficient and broadly applicable at various levels of plant biomass-based bioenergy research. The use of plant cell wall glycan-directed probes has seen increasing use over the past decade as an excellent approach for the detailed characterization of cell walls. Large collections of such probes directed against most major cell wall glycans are currently available worldwide. The largest and most diverse set of such probes consists of cell wall glycan-directed monoclonal antibodies (McAbs). These McAbs can be used as immunological probes to comprehensively monitor the overall presence, extractability, and distribution patterns among cell types of most major cell wall glycan epitopes using two mutually complementary immunological approaches, glycome profiling (an in vitro platform) and immunolocalization (an in situ platform). Significant progress has been made recently in the overall understanding of plant biomass structure, composition, and modifications with the application of these immunological approaches. This review focuses on such advances made in plant biomass analyses across diverse areas of bioenergy research.

  12. MICRONUTRIENTS AND BIOMASS IN Eucalyptus dunnii Maiden STAND

    Directory of Open Access Journals (Sweden)

    Grasiele Dick

    Full Text Available ABSTRACT The expansion of silviculture in Brazil, and the consequent intensive practices for soil preparation with high demand for fertilizers require sustainable nutrient management of forest sites. The objective of this study was to quantify the biomass and the micronutrient stocks of a 60-month-old Eucalyptus dunnii stand established in Alegrete, Rio Grande do Sul. The stand was established in a Rhodic Paleudult soil with low fertility and texture varying between sandy loam and sandy-clay loam. For the sampling of stand biomass, twelve trees were harvested, sectioned at ground level, and subsequently fractionated into the components roots, leaves, branches, stembark and stemwood to determine the dry mass and micronutrient content. The total biomass of the stand was 67.49 Mg ha-1, with mass allocation in descending order from: stem wood > root > bark > branches > leaves. Total micronutrient stocks for boron (B, copper (Cu, iron (Fe, manganese (Mn and zinc (Zn were 562.57, 401.46, 9913.28, 31877.82, and 766.96 g ha-1, respectively. In addition, we found greater accumulation of Zn in the wood, high Mn accumulation especially in the bark, and high Fe content in the roots. Therefore, based on these micronutrient levels and their allocation between biomass fractions, we emphasize that the practice of retaining forest residues on-site after harvest is essential for forest nutrition through nutrient cycling and for soil conservation and fertility.

  13. [Effects of drip irrigation under mulching on cotton root and shoot biomass and yield].

    Science.gov (United States)

    Yan, Ying-Yu; Zhao, Cheng-Yi; Sheng, Yu; Li, Ju-Yan; Peng, Dong-Mei; Li, Zi-Liang; Feng, Sheng-Li

    2009-04-01

    By using bidirectional sampling method with soil drill, the effects of different amounts of drip irrigation (2618, 2947, 3600 and 4265 m3 x hm(-2)) under mulching on the root distribution, aboveground growth, and yield of cotton was studied in field. The results indicated that irrigation amount affected the root and shoot growth significantly. In all irrigation treatments, cotton root was mainly distributed in mulched area, occupying 60.65%-73.45% of total root biomass, while only 39.35%-26.55% was distributed in bare area. Water stress increased rooting depth, root biomass, and the extent of lateral rooting. Significant differences were observed in the biological characteristics and the biomass accumulation and allocation of cotton plant among different irrigation treatments. Over-irrigation (4265 m3 x hm(-2)) increased plant height, width of inverse fourth leaf, and amounts of branch and bud, and thus, accelerated biomass accumulation rate. Over-irrigation also increased the root/shoot ratio and the proportion of biomass allocated to vegetative organs, but increased the fruit abscission rate and therefore reduced the economic yield. It was suggested that both excessive soil moisture content and water stress could affect the biomass accumulation and allocation in different cotton organs and at various life stages. Under the conditions of our experiment, 3600 m3 x hm(-2) was the optimal irrigation amount.

  14. Flexibility of resource allocation in a hermaphroditic-gynomonoecious herb through deployment of female and male resources in perfect flowers.

    Science.gov (United States)

    Mamut, Jannathan; Xiong, Ying-Ze; Tan, Dun-Yan; Huang, Shuang-Quan

    2017-03-01

    It has been hypothesized that two flower types permit flexible allocation of resources to female and male functions, yet empirical evidence for the sex-allocation hypothesis remains scarce in gynomonoecious species. To characterize resource allocation to pistillate and perfect flowers and allocation of perfect flowers between gynomonoecious and hermaphroditic individuals, we examined the flexibility and whether female-biased allocation increases with plant size in the hermaphroditic-gynomonoecious herb Eremurus anisopterus . Frequency of gynomonoecious individuals, flower production, and plant size were investigated in different populations. Floral allocation was compared among the three flower types of E. anisopterus . Frequency of gynomonoecious plants varied from 2-17% in nine populations. Only larger plants produced female flowers at the bottom of racemes. Both female and perfect flower production tended to increase proportionately with plant size in gynomonoecious individuals. Female flowers did not produce less biomass than perfect flowers from hermaphroditic or gynomonoecious plants. However, both female and perfect flowers from gynomonoecious individuals had lighter stamen mass, but larger pistil mass, than perfect flowers from hermaphrodites. Although the prediction of an increase in female flower number with plant size was not observed in E. anisopterus , the flexibility of sex allocation in gynomonoecious species was confirmed in that gynomonoecious individuals had a female-biased floral allocation compared to hermaphroditic individuals. Such comparisons of gynomonoecious to hermaphroditic individuals permit us to unveil a sexual adjustment strategy: flexibility of sexual investments within plants. © 2017 Botanical Society of America.

  15. Solid biomass barometer 2011

    International Nuclear Information System (INIS)

    2012-01-01

    The winter of 2011 was exceptionally mild, even in Northern Europe, with unusually warm temperatures. As a result the demand for firewood and solid biomass fuel was low. The European Union's primary energy production from solid biomass contracted by 2.9% slipping to 78.8 Mtoe. The first 4 countries are Germany (11.690 Mtoe), France (9.223 Mtoe), Sweden (8.165 Mtoe) and Finland (7.476 Mtoe) and when the production is relative to the population the first 4 countries become: Finland (1.391 toe/inhab.), Sweden (0.867 toe/inhab.), Latvia (0.784 toe/inhab.) and Estonia (0.644 toe/inhab.). Solid biomass electricity production continued to grow, driven by the additional take-up of biomass co-firing, to reach 72.800 TWh at the end of 2011, it means +2.6% compared to 2010. The energy policy of various states concerning solid biomass is analyzed

  16. Sex-related differences in reproductive allocation, growth, defense and herbivory in three dioecious neotropical palms.

    Directory of Open Access Journals (Sweden)

    Verónica Cepeda-Cornejo

    2010-03-01

    Full Text Available Frequently, in dioecious plants, female plants allocate more resources to reproduction than male plants. Therefore it is expected that asymmetrical allocation to reproduction may lead to a reproduction-growth tradeoff, whereby female plants grow less than male plants, but invest more in defenses and thus experience lower herbivory than male plants.We tested these expectations by comparing resource allocation to reproduction, growth and defense and its consequences on herbivory in three sympatric dioecious Chamaedorea palms (C. alternans, C. pinnatifrons and C. ernesti-augusti using a pair-wise design (replicated male/female neighboring plants in a Mexican tropical rain forest. Our findings support the predictions. Biomass allocation to reproduction in C. pinnatifrons was 3-times higher in female than male plants, consistent with what is known in C. alternans and C. ernesti-augusti. Growth (height and leaf production rate and biomass production was higher in male plants of all three species. Female plants of the three species had traits that suggest greater investment in defense, as they had 4-16% tougher leaves, and 8-18% higher total phenolic compounds concentration. Accordingly, female plants sustained 53-78% lower standing herbivory and 49-87% lower herbivory rates than male plants.Our results suggests that resource allocation to reproduction in the studied palms is more costly to female plants and this leads to predictable intersexual differences in growth, defense and herbivory. We conclude that resource allocation to reproduction in plants can have important consequences that influence their interaction with herbivores. Since herbivory is recognized as an important selective force in plants, these results are of significance to our understanding of plant defense evolution.

  17. Peer-Allocated Instant Response (PAIR): Computional allocation of peer tutors in learning communities

    NARCIS (Netherlands)

    Westera, Wim

    2009-01-01

    Westera, W. (2007). Peer-Allocated Instant Response (PAIR): Computational allocation of peer tutors in learning communities. Journal of Artificial Societies and Social Simulation, http://jasss.soc.surrey.ac.uk/10/2/5.html

  18. The role of physical formidability in human social status allocation.

    Science.gov (United States)

    Lukaszewski, Aaron W; Simmons, Zachary L; Anderson, Cameron; Roney, James R

    2016-03-01

    Why are physically formidable men willingly allocated higher social status by others in cooperative groups? Ancestrally, physically formidable males would have been differentially equipped to generate benefits for groups by providing leadership services of within-group enforcement (e.g., implementing punishment of free riders) and between-group representation (e.g., negotiating with other coalitions). Therefore, we hypothesize that adaptations for social status allocation are designed to interpret men's physical formidability as a cue to these leadership abilities, and to allocate greater status to formidable men on this basis. These hypotheses were supported in 4 empirical studies wherein young adults rated standardized photos of subjects (targets) who were described as being part of a white-collar business consultancy. In Studies 1 and 2, male targets' physical strength positively predicted ratings of their projected status within the organization, and this effect was mediated by perceptions that stronger men possessed greater leadership abilities of within-group enforcement and between-group representation. Moreover, (a) these same patterns held whether status was conceptualized as overall ascendancy, prestige-based status, or dominance-based status, and (b) strong men who were perceived as aggressively self-interested were not allocated greater status. Finally, 2 experiments established the causality of physical formidability's effects on status-related perceptions by manipulating targets' relative strength (Study 3) and height (Study 4). In interpreting our findings, we argue that adaptations for formidability-based status allocation may have facilitated the evolution of group cooperation in humans and other primates. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  19. Biomass ash utilization

    Energy Technology Data Exchange (ETDEWEB)

    Bristol, D.R.; Noel, D.J.; O`Brien, B. [HYDRA-CO Operations, Inc., Syracuse, NY (United States); Parker, B. [US Energy Corp., Fort Fairfield, ME (United States)

    1993-12-31

    This paper demonstrates that with careful analysis of ash from multiple biomass and waste wood fired power plants that most of the ash can serve a useful purpose. Some applications require higher levels of consistency than others. Examples of ash spreading for agricultural purposes as a lime supplement for soil enhancement in Maine and North Carolina, as well as a roadbase material in Maine are discussed. Use of ash as a horticultural additive is explored, as well as in composting as a filtering media and as cover material for landfills. The ash utilization is evaluated in a framework of environmental responsibility, regulations, handling and cost. Depending on the chemical and physical properties of the biomass derived fly ash and bottom ash, it can be used in one or more applications. Developing a program that utilizes ash produced in biomass facilities is environmentally and socially sound and can be financially attractive.

  20. Northeast Regional Biomass Program

    International Nuclear Information System (INIS)

    O'Connell, R.A.

    1991-11-01

    The management structure and program objectives for the Northeast Regional Biomass Program (NRBP) remain unchanged from previous years. Additional funding was provided by the Bonneville Power Administration Regional Biomass Program to continue the publication of articles in the Biologue. The Western Area Power Administration and the Council of Great Lakes Governors funded the project ''Characterization of Emissions from Burning Woodwaste''. A grant for the ninth year was received from DOE. The Northeast Regional Biomass Steering Committee selected the following four projects for funding for the next fiscal year. (1) Wood Waste Utilization Conference, (2) Performance Evaluation of Wood Systems in Commercial Facilities, (3) Wood Energy Market Utilization Training, (4) Update of the Facility Directory

  1. YEAR 2 BIOMASS UTILIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Christopher J. Zygarlicke

    2004-11-01

    This Energy & Environmental Research Center (EERC) Year 2 Biomass Utilization Final Technical Report summarizes multiple projects in biopower or bioenergy, transportation biofuels, and bioproducts. A prototype of a novel advanced power system, termed the high-temperature air furnace (HITAF), was tested for performance while converting biomass and coal blends to energy. Three biomass fuels--wood residue or hog fuel, corn stover, and switchgrass--and Wyoming subbituminous coal were acquired for combustion tests in the 3-million-Btu/hr system. Blend levels were 20% biomass--80% coal on a heat basis. Hog fuel was prepared for the upcoming combustion test by air-drying and processing through a hammer mill and screen. A K-Tron biomass feeder capable of operating in both gravimetric and volumetric modes was selected as the HITAF feed system. Two oxide dispersion-strengthened (ODS) alloys that would be used in the HITAF high-temperature heat exchanger were tested for slag corrosion rates. An alumina layer formed on one particular alloy, which was more corrosion-resistant than a chromia layer that formed on the other alloy. Research activities were completed in the development of an atmospheric pressure, fluidized-bed pyrolysis-type system called the controlled spontaneous reactor (CSR), which is used to process and condition biomass. Tree trimmings were physically and chemically altered by the CSR process, resulting in a fuel that was very suitable for feeding into a coal combustion or gasification system with little or no feed system modifications required. Experimental procedures were successful for producing hydrogen from biomass using the bacteria Thermotoga, a deep-ocean thermal vent organism. Analytical procedures for hydrogen were evaluated, a gas chromatography (GC) method was derived for measuring hydrogen yields, and adaptation culturing and protocols for mutagenesis were initiated to better develop strains that can use biomass cellulose. Fly ash derived from

  2. Aerosols from biomass combustion

    Energy Technology Data Exchange (ETDEWEB)

    Nussbaumer, T.

    2001-07-01

    This report is the proceedings of a seminar on biomass combustion and aerosol production organised jointly by the International Energy Agency's (IEA) Task 32 on bio energy and the Swiss Federal Office of Energy (SFOE). This collection of 16 papers discusses the production of aerosols and fine particles by the burning of biomass and their effects. Expert knowledge on the environmental impact of aerosols, formation mechanisms, measurement technologies, methods of analysis and measures to be taken to reduce such emissions is presented. The seminar, visited by 50 participants from 11 countries, shows, according to the authors, that the reduction of aerosol emissions resulting from biomass combustion will remain a challenge for the future.

  3. Biomass for bioenergy

    DEFF Research Database (Denmark)

    Bentsen, Niclas Scott

    sources of biomass for energy purposes in the European Union. Estimation of European biomass resources is associated with significant uncertainty, and it is not sure if the European Union can meet its 2020 energy policy targets with biomass produced in the EU, although some countries hold sway over...... a total production of residues from these six crops of ~3.7 billion tonnes dry matter annually. North and South America; Eastern, South-Eastern and Southern Asia and Eastern Europe each produce more than 200 million tonnes dry matter annually. The theoretical energy potential from the selected crop......, where bio-ethanol production is integrated with combined heat and power production may improve the energy balance with about 30 % point and reach energy efficiencies almost comparable to those seen for conversion of petroleum into gasoline. Minimisation of GHG emissions from bioenergy production...

  4. Biomass Deconstruction and Recalcitrance

    DEFF Research Database (Denmark)

    Zhang, Heng

    reflections of plant species, tissue or organ types, genetic traits and environment. Effects of cultivar type, anatomical distribution, chemical composition, fertilizer level and growth year have been observed during in vitro and in vivo trials. A similar approach is here taken to further investigate: 1). How...... as an important parameter affecting the bio-degradability during enzymatic saccharification. The leaf fraction (leaf blade and sheath), which contributes up to 50 % of the whole wheat straw on a weight basis, is more degradable than the stem fraction via a biochemical process. Water was used to assess...... level of different biomasses. The knowledge on wheat straw biomass gained from this thesis work may be translated to more focused plant breeding research for 2G ethanol production, and the Copenhagen HTS platform is an ideal tool for screening large biomass sample set. The success of lignocellulosic...

  5. Credit allocation for research institutes

    Science.gov (United States)

    Wang, J.-P.; Guo, Q.; Yang, K.; Han, J.-T.; Liu, J.-G.

    2017-05-01

    It is a challenging work to assess research performance of multiple institutes. Considering that it is unfair to average the credit to the institutes which is in the different order from a paper, in this paper, we present a credit allocation method (CAM) with a weighted order coefficient for multiple institutes. The results for the APS dataset with 18987 institutes show that top-ranked institutes obtained by the CAM method correspond to well-known universities or research labs with high reputation in physics. Moreover, we evaluate the performance of the CAM method when citation links are added or rewired randomly quantified by the Kendall's Tau and Jaccard index. The experimental results indicate that the CAM method has better performance in robustness compared with the total number of citations (TC) method and Shen's method. Finally, we give the first 20 Chinese universities in physics obtained by the CAM method. However, this method is valid for any other branch of sciences, not just for physics. The proposed method also provides universities and policy makers an effective tool to quantify and balance the academic performance of university.

  6. Time allocation of disabled individuals.

    Science.gov (United States)

    Pagán, Ricardo

    2013-05-01

    Although some studies have analysed the disability phenomenon and its effect on, for example, labour force participation, wages, job satisfaction, or the use of disability pension, the empirical evidence on how disability steals time (e.g. hours of work) from individuals is very scarce. This article examines how disabled individuals allocate their time to daily activities as compared to their non-disabled counterparts. Using time diary information from the Spanish Time Use Survey (last quarter of 2002 and the first three quarters of 2003), we estimate the determinants of time (minutes per day) spent on four aggregate categories (market work, household production, tertiary activities and leisure) for a sample of 27,687 non-disabled and 5250 disabled individuals and decompose the observed time differential by using the Oaxaca-Blinder methodology. The results show that disabled individuals devote less time to market work (especially females), and more time to household production (e.g. cooking, cleaning, child care), tertiary activities (e.g., sleeping, personal care, medical treatment) and leisure activities. We also find a significant effect of age on the time spent on daily activities and important differences by gender and disability status. The results are consistent with the hypothesis that disability steals time, and reiterate the fact that more public policies are needed to balance working life and health concerns among disabled individuals. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Biomass living energy

    International Nuclear Information System (INIS)

    2005-01-01

    Any energy source originating from organic matter is biomass, which even today is the basic source of energy for more than a quarter of humanity. Best known for its combustible properties, biomass is also used to produce biofuels. This information sheet provides also information on the electricity storage from micro-condensers to hydroelectric dams, how to save energy facing the increasing of oil prices and supply uncertainties, the renewable energies initiatives of Cork (Ireland) and the Switzerland european energy hub. (A.L.B.)

  8. Biomass stoves in dwellings

    DEFF Research Database (Denmark)

    Luis Teles de Carvalho, Ricardo

    and analyzed in this session. Experimental results regarding the performance of biomass combustion stoves and the effects of real-life practices in terms of thermal efficiency, particulate and gaseous emissions will be addressed. This research is based on the development of a new testing approach that combines...... laboratory and field measurements established in the context of the implications of the upcoming eco-design directive. The communication will cover technical aspects concerning the operating performance of different types of biomass stoves and building envelopes, in order to map the ongoing opportunities...

  9. Resource allocation based on cost efficiency

    DEFF Research Database (Denmark)

    Dehnokhalaji, Akram; Ghiyasi, Mojtaba; Korhonen, Pekka

    2017-01-01

    In this paper, we consider a resource allocation (RA) problem and develop an approach based on cost (overall) efficiency. The aim is to allocate some inputs among decision making units (DMUs) in such way that their cost efficiencies improve or stay unchanged after RA. We formulate a multi...... examples and an empirical illustration are also provided....

  10. 'Unconscionable and irrational' SAPS human resource allocation ...

    African Journals Online (AJOL)

    These areas also suffer among the highest rates of murder and serious violent crime in the province. The allocation of human resources to policing impinges on various constitutional rights. Given the inequity and irrationality apparent in the allocation of police personnel, the Khayelitsha Commission recommended that this ...

  11. Nash Social Welfare in Multiagent Resource Allocation

    NARCIS (Netherlands)

    S. Ramezani (Sara); U. Endriss; E. David; E.H. Gerding (Enrico); D. Sarne; O. Shehory (Onn)

    2010-01-01

    htmlabstractWe study different aspects of the multiagent resource allocation problem when the objective is to find an allocation that maximizes Nash social welfare, the product of the utilities of the individual agents. The Nash solution is an important welfare criterion that combines efficiency and

  12. Obtaining a Proportional Allocation by Deleting Items

    NARCIS (Netherlands)

    Dorn, B.; de Haan, R.; Schlotter, I.; Röthe, J.

    2017-01-01

    We consider the following control problem on fair allocation of indivisible goods. Given a set I of items and a set of agents, each having strict linear preference over the items, we ask for a minimum subset of the items whose deletion guarantees the existence of a proportional allocation in the

  13. Risk and reliability allocation to risk control

    International Nuclear Information System (INIS)

    Vojnovic, D.; Kozuh, M.

    1992-01-01

    The risk allocation procedure is used as an analytical model to support the optimal decision making for reliability/availability improvement planning. Both levels of decision criteria, the plant risk measures and plant performance indices, are used in risk allocation procedure. Decision support system uses the multi objective decision making concept. (author) [sl

  14. Optimal Allocation in Stratified Randomized Response Model

    Directory of Open Access Journals (Sweden)

    Javid Shabbir

    2005-07-01

    Full Text Available A Warner (1965 randomized response model based on stratification is used to determine the allocation of samples. Both linear and log-linear cost functions are discussed under uni and double stratification. It observed that by using a log-linear cost function, one can get better allocations.

  15. Bounds in the location-allocation problem

    DEFF Research Database (Denmark)

    Juel, Henrik

    1981-01-01

    Develops a family of stronger lower bounds on the objective function value of the location-allocation problem. Solution methods proposed to solve problems in location-allocation; Efforts to develop a more efficient bound solution procedure; Determination of the locations of the sources....

  16. Allometric scaling relationship between above- and below-ground biomass within and across five woody seedlings.

    Science.gov (United States)

    Cheng, Dongliang; Ma, Yuzhu; Zhong, Quanling; Xu, Weifeng

    2014-10-01

    Allometric biomass allocation theory predicts that leaf biomass (M L ) scaled isometrically with stem (M S ) and root (M R ) biomass, and thus above-ground biomass (leaf and stem) (M A ) and root (M R ) scaled nearly isometrically with below-ground biomass (root) for tree seedlings across a wide diversity of taxa. Furthermore, prior studies also imply that scaling constant should vary with species. However, litter is known about whether such invariant isometric scaling exponents hold for intraspecific biomass allocation, and how variation in scaling constants influences the interspecific scaling relationship between above- and below-ground biomass. Biomass data of seedlings from five evergreen species were examined to test scaling relationships among biomass components across and within species. Model Type II regression was used to compare the numerical values of scaling exponents and constants among leaf, stem, root, and above- to below-ground biomass. The results indicated that M L and M S scaled in an isometric or a nearly isometric manner with M R , as well as M A to M R for five woody species. Significant variation was observed in the Y-intercepts of the biomass scaling curves, resulting in the divergence for intraspecific scaling and interspecific scaling relationships for M L versus M S and M L versus M R , but not for M S versus M R and M A versus M R . We conclude, therefore, that a nearly isometric scaling relationship of M A versus M R holds true within each of the studied woody species and across them irrespective the negative scaling relationship between leaf and stem.

  17. Effect of stand structure on models for volume and aboveground biomass assessment (Castelfusano pinewood, Roma

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available The main purpose of this research was to analyse the effects of stand structure on biomass allocation and on the accurancy of estimation models for volume and aboveground biomass of Italian stone pine (Pinus pinea L.. Although the species is widely distributed on Mediterranean coasts, few studies on forest biomass estimation have focused on pinewoods. The research was carried out in the Castelfusano’s pinewood (Rome and concerned the two most common structural types: (a 50 years-old pinewood originated by broadcast seeding; and (b 62 years-old pinewood originated by partial seeding alternating worked strips to firm strips. Some 83 sample trees were selected for stem volume estimation and a subset of 32 trees used to quantify the total epigeous biomass, the wooden biomass compartment, including stem and big branches (diameter > 3 cm and the photosynthetic biomass, including thin branches (diameter < 3 cm and needles. Collected data were used to elaborate allometric relations for stem volume, total biomass and specific relations for both compartments, based on one (d2 or two (d2h indipendent variables, for both structural types. Furthermore, pinewood specific biomass expansion factors (BEF - indexes used to estimate carbon stocks starting from stem biomass data - were obtained. The achieved estimation models were subjected to both parallelism and coincidence tests, showing significant effects of stand structure on the accurancy of the allometric relations. The effects of stand structure and reliability of tree height curves on the accurancy of estimation models for volume and aboveground biomass and on biomass allocation in different compartments are analysed and discussed.

  18. Method for pretreating lignocellulosic biomass

    Science.gov (United States)

    Kuzhiyil, Najeeb M.; Brown, Robert C.; Dalluge, Dustin Lee

    2015-08-18

    The present invention relates to a method for pretreating lignocellulosic biomass containing alkali and/or alkaline earth metal (AAEM). The method comprises providing a lignocellulosic biomass containing AAEM; determining the amount of the AAEM present in the lignocellulosic biomass; identifying, based on said determining, the amount of a mineral acid sufficient to completely convert the AAEM in the lignocellulosic biomass to thermally-stable, catalytically-inert salts; and treating the lignocellulosic biomass with the identified amount of the mineral acid, wherein the treated lignocellulosic biomass contains thermally-stable, catalytically inert AAEM salts.

  19. Optimal allocation of reviewers for peer feedback

    DEFF Research Database (Denmark)

    Wind, David Kofoed; Jensen, Ulf Aslak; Jørgensen, Rasmus Malthe

    2017-01-01

    to submissions in such a way that all submissions receive feedback of similar quality and that we are able to significantly outperform simple random allocation of reviewers. Additionally we investigate the effect of pre-allocating reviews in comparison to allocating reviewers live during the review process......Peer feedback is the act of letting students give feedback to each other on submitted work. There are multiple reasons to use peer feedback, including students getting more feedback, time saving for teachers and increased learning by letting students reflect on work by others. In order for peer...... feedback to be effective students should give and receive useful feedback. A key challenge in peer feedback is allocating the feedback givers in a good way. It is important that reviewers are allocated to submissions such that the feedback distribution is fair - meaning that all students receive good...

  20. Optimal allocation of resources in systems

    International Nuclear Information System (INIS)

    Derman, C.; Lieberman, G.J.; Ross, S.M.

    1975-01-01

    In the design of a new system, or the maintenance of an old system, allocation of resources is of prime consideration. In allocating resources it is often beneficial to develop a solution that yields an optimal value of the system measure of desirability. In the context of the problems considered in this paper the resources to be allocated are components already produced (assembly problems) and money (allocation in the construction or repair of systems). The measure of desirability for system assembly will usually be maximizing the expected number of systems that perform satisfactorily and the measure in the allocation context will be maximizing the system reliability. Results are presented for these two types of general problems in both a sequential (when appropriate) and non-sequential context

  1. A closer look at cognitive control: Differences in resource allocation during updating, inhibition and switching as revealed by pupillometry

    NARCIS (Netherlands)

    Rondeel, E.W.M.; Steenbergen, H. van; Holland, R.W.; Knippenberg, A.F.M. van

    2015-01-01

    The present study investigated resource allocation, as measured by pupil dilation, in tasks measuring updating (2 Back task), inhibition (Stroop task) and switching (Number Switch task). Because each cognitive control component has unique characteristics, differences in patterns of resource

  2. Simulating Water Allocation and Cropping Decisions in Yemen’s Abyan Delta Spate Irrigation System

    Directory of Open Access Journals (Sweden)

    Derek Jin-Uk Marchant

    2018-01-01

    Full Text Available Agriculture employs more Yemenis than any other sector and spate irrigation is the largest source of irrigation water. Spate irrigation however is growing increasingly difficult to sustain in many areas due to water scarcity and unclear sharing of water amongst users. In some areas of Yemen, there are no institutionalised water allocation rules which can lead to water related disputes. Here, we propose a proof-of-concept model to evaluate the impacts of different water allocation patterns to assist in devising allocation rules. The integrated model links simple wadi flow, diversion, and soil moisture-yield simulators to a crop decision model to evaluate impacts of different water allocation rules and their possible implications on local agriculture using preliminary literature data. The crop choice model is an agricultural production model of irrigation command areas where the timing, irrigated area and crop mix is decided each month based on current conditions and expected allocations. The model is applied to Yemen’s Abyan Delta, which has the potential to be the most agriculturally productive region in the country. The water allocation scenarios analysed include upstream priority, downstream priority, equal priority (equal sharing of water shortages, and a user-defined mixed priority that gives precedence to different locations based on the season. Once water is distributed according to one of these allocation patterns, the model determines the profit-maximising plant date and crop selection for 18 irrigated command areas. This aims to estimate the impacts different water allocation strategies could have on livelihoods. Initial results show an equal priority allocation is the most equitable and efficient, with 8% more net benefits than an upstream scenario, 10% more net benefits than a downstream scenario, and 25% more net benefits than a mixed priority.

  3. 2009 Biomass Program Peer Review Report

    Energy Technology Data Exchange (ETDEWEB)

    Ferrell, John [Office of Energy Efficiency and Renewable Energy (EERE), Washington, DC (United States)

    2009-12-01

    This document summarizes the recommendations and evaluations provided by an independent external panel of experts at the U.S. Department of Energy Biomass Program‘s 2009 peer review meeting, held on July 14–15, 2009, in Arlington, Virginia. The document also includes summary information from the six separate platform reviews conducted between March and April 2009 in the Washington, D.C., and Denver, Colorado, areas. The platform reviews provide evaluations of the program‘s projects in applied research, development, and demonstration as well as analysis and deployment activities. The July program peer review was an evaluation of the program‘s overall strategic planning, management approach, priorities across research areas, and resource allocation.

  4. Biomass co-firing

    DEFF Research Database (Denmark)

    Yin, Chungen

    2013-01-01

    Co-firing biomass with fossil fuels in existing power plants is an attractive option for significantly increasing renewable energy resource utilization and reducing CO2 emissions. This chapter mainly discusses three direct co-firing technologies: pulverized-fuel (PF) boilers, fluidized-bed combus...

  5. Pyrolysis of chitin biomass

    DEFF Research Database (Denmark)

    Qiao, Yan; Chen, Shuai; Liu, Ying

    2015-01-01

    The thermal degradation of chitin biomass with various molecular structures was investigated by thermogravimetric analysis (TG), and the gaseous products were analyzed by connected mass spectroscopy (MS). The chemical structure and morphology of char residues collected at 750°C using the model...

  6. Biomass Conversion Factsheet

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-05

    To efficiently convert algae, diverse types of cellulosic biomass, and emerging feedstocks into renewable fuels, the U.S. Department of Energy (DOE) supports research, development, and demonstration of technologies. This research will help ensure that these renewable fuels are compatible with today’s vehicles and infrastructure.

  7. Energy from aquatic biomass

    International Nuclear Information System (INIS)

    Aresta, M.; Dibenedetto, A.

    2009-01-01

    Aquatic biomass is considered as a second (or third) generation option for the production of bio fuels. The best utilization for energy purposes is not its direct combustion. Several technologies are available for the extraction of compounds that may find application for the production of gaseous fuels (biogas, dihydrogen) or liquid fuels (ethanol, bio oil, biodiesel). [it

  8. The UK biomass industry

    International Nuclear Information System (INIS)

    Billins, P.

    1998-01-01

    A brief review is given of the development of the biomass industry in the UK. Topics covered include poultry litter generation of electricity, gasification plants fuelled by short-rotation coppice, on-farm anaerobic digestion and specialized combustion systems, e.g. straw, wood and other agricultural wastes. (UK)

  9. Biomass yield and biomass functions for plantation grown Nauclea ...

    African Journals Online (AJOL)

    This paper presents biomass yield and functions for estimating total above ground biomass (TAGB), stem, branch and foliage biomass for even-aged plantations of Nauclea diderrichii (Opepe) in Nigeria. Data were obtained from 81 trees, harvested from stands of different ages. TAGB of Opepe ranged from 32.5 t ha-1 (5 ...

  10. Interspecific differences in whole-plant respiration vs. biomass scaling relationships: a case study using evergreen conifer and angiosperm tree seedlings.

    Science.gov (United States)

    Cheng, Dongliang; Niklas, Karl J; Zhong, Quanlin; Yang, Yusheng; Zhang, Jianhua

    2014-04-01

    Empirical studies and theory indicate that respiration rates (R) of small plants scale nearly isometrically with both leaf biomass (ML) and total plant biomass (MT). These predictions are based on angiosperm species and apply only across a small range of body mass. Whether these relationships hold true for different plants, such as conifers, remains unclear. We tested these predictions using the whole-plant maintenance respiration rates and the biomass allocation patterns of the seedlings of two conifer tree species and two angiosperm tree species. Model Type II regression protocols were used to compare the scaling exponents (α) and normalization constants (β) across all four species and within each of the four species. The data show that the scaling exponents varied among the four species and that all differed significantly from isometry. For conifers, scaling exponents for R vs. MT, and R and ML were numerically smaller than those of the broadleaved angiosperm species. However, across the entire data set, R scaled isometrically with ML and with MT as predicted by the West, Brown, and Enquist (WBE) theory. We also observed higher respiration rates for small conifer seedlings compared to comparably sized angiosperm seedlings. Our data add credence to the view that the R vs. M scaling relationship differs among species, and that in general, the numerical values of this interspecific scaling relationship will depend on the species pooled in the analysis and on the range of body sizes within the data set.

  11. Carbon Fiber from Biomass

    Energy Technology Data Exchange (ETDEWEB)

    Milbrandt, Anelia [Clean Energy Manufacturing Analysis Center, Godlen, CO (United States); Booth, Samuel [Clean Energy Manufacturing Analysis Center, Godlen, CO (United States)

    2016-09-01

    Carbon fiber (CF), known also as graphite fiber, is a lightweight, strong, and flexible material used in both structural (load-bearing) and non-structural applications (e.g., thermal insulation). The high cost of precursors (the starting material used to make CF, which comes predominately from fossil sources) and manufacturing have kept CF a niche market with applications limited mostly to high-performance structural materials (e.g., aerospace). Alternative precursors to reduce CF cost and dependence on fossil sources have been investigated over the years, including biomass-derived precursors such as rayon, lignin, glycerol, and lignocellulosic sugars. The purpose of this study is to provide a comprehensive overview of CF precursors from biomass and their market potential. We examine the potential CF production from these precursors, the state of technology and applications, and the production cost (when data are available). We discuss their advantages and limitations. We also discuss the physical properties of biomass-based CF, and we compare them to those of polyacrylonitrile (PAN)-based CF. We also discuss manufacturing and end-product considerations for bio-based CF, as well as considerations for plant siting and biomass feedstock logistics, feedstock competition, and risk mitigation strategies. The main contribution of this study is that it provides detailed technical and market information about each bio-based CF precursor in one document while other studies focus on one precursor at a time or a particular topic (e.g., processing). Thus, this publication allows for a comprehensive view of the CF potential from all biomass sources and serves as a reference for both novice and experienced professionals interested in CF production from alternative sources.

  12. Enzymes for improved biomass conversion

    Science.gov (United States)

    Brunecky, Roman; Himmel, Michael E.

    2016-02-02

    Disclosed herein are enzymes and combinations of the enzymes useful for the hydrolysis of cellulose and the conversion of biomass. Methods of degrading cellulose and biomass using enzymes and cocktails of enzymes are also disclosed.

  13. Catalytic Gasification of Lignocellulosic Biomass

    NARCIS (Netherlands)

    Chodimella, Pramod; Seshan, Kulathuiyer; Schlaf, Marcel; Zhang, Z. Conrad

    2015-01-01

    Gasification of lignocellulosic biomass has attracted substantial current research interest. Various possible routes to convert biomass to fuels have been explored. In the present chapter, an overview of the gasification processes and their possible products are discussed. Gasification of solid

  14. Entrained Flow Gasification of Biomass

    DEFF Research Database (Denmark)

    Qin, Ke

    The present Ph. D. thesis describes experimental and modeling investigations on entrained flow gasification of biomass and an experimental investigation on entrained flow cogasification of biomass and coal. A review of the current knowledge of biomass entrained flow gasification is presented....... Biomass gasification experiments were performed in a laboratory-scale atmospheric pressure entrained flow reactor with the aim to investigate the effects of operating parameters and biomass types on syngas products. A wide range of operating parameters was involved: reactor temperature, steam/carbon ratio......, excess air ratio, oxygen concentration, feeder gas flow, and residence time. Wood, straw, and lignin were used as biomass fuels. In general, the carbon conversion was higher than 90 % in the biomass gasification experiments conducted at high temperatures (> 1200 °C). The biomass carbon...

  15. Biomass Feedstock National User Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Bioenergy research at the Biomass Feedstock National User Facility (BFNUF) is focused on creating commodity-scale feed-stocks from native biomass that meet the needs...

  16. Catalytic pyrolysis of lignocellulosic biomass

    NARCIS (Netherlands)

    Seshan, Kulathuiyer; Sa, Jacinto

    2014-01-01

    This chapter reports on the latest developments of biomass catalytic pyrolysis for the production of fuels. The primary focus is on the role of catalysts in the process, namely, their influence in the liquefaction of lignocellulosic biomass.

  17. Temporal species richness-biomass relationships along successional gradients

    Science.gov (United States)

    Guo, Q.

    2003-01-01

    Diversity-biomass relationships are frequently reported to be hump-shaped over space at a given time. However, it is not yet clear how diversity and biomass change simultaneously and how they are related to each other over time (e.g. in succession) at one locality. This study develops a temporal model based on the projected changes of various community variables in a generalized terrestrial environment after fire and uses post-fire succession data on Santa Monica Mountains of southern California and other published succession data to examine the temporal diversity-biomass relationships. The results indicate that in the early stages of succession, both diversity and biomass increase and a positive relationship appears, while in the late stages of succession, biomass continued to increase but diversity usually declines; thus a negative relationship may be observed. When the scales of measurement become sufficiently large so that the measured diversity and biomass cross various stages of succession, a 'hump-shaped' relationship can emerge. The diversity-biomass relationship appears to be concordant in space and time when appropriate scales are used. Formerly proposed explanations for spatial patterns may well apply to the temporal patterns (particularly colonization, facilitation and competitive exclusion).

  18. Romania biomass energy. Country study

    International Nuclear Information System (INIS)

    Burnham, M.; Easterly, J.L.; Mark, P.E.; Keller, A.

    1995-01-01

    The present report was prepared under contract to UNIDO to conduct a case study of biomass energy use and potential in Romania. The purpose of the case study is to provide a specific example of biomass energy issues and potential in the context of the economic transition under way in eastern Europe. The transition of Romania to a market economy is proceeding at a somewhat slower pace than in other countries of eastern Europe. Unfortunately, the former regime forced the use of biomass energy with inadequate technology and infrastructure, particularly in rural areas. The resulting poor performance thus severely damaged the reputation of biomass energy in Romania as a viable, reliable resource. Today, efforts to rejuvenate biomass energy and tap into its multiple benefits are proving challenging. Several sound biomass energy development strategies were identified through the case study, on the basis of estimates of availability and current use of biomass resources; suggestions for enhancing potential biomass energy resources; an overview of appropriate conversion technologies and markets for biomass in Romania; and estimates of the economic and environmental impacts of the utilization of biomass energy. Finally, optimal strategies for near-, medium- and long-term biomass energy development, as well as observations and recommendations concerning policy, legislative and institutional issues affecting the development of biomass energy in Romania are presented. The most promising near-term biomass energy options include the use of biomass in district heating systems; cofiring of biomass in existing coal-fired power plants or combined heat and power plants; and using co-generation systems in thriving industries to optimize the efficient use of biomass resources. Mid-term and long-term opportunities include improving the efficiency of wood stoves used for cooking and heating in rural areas; repairing the reputation of biogasification to take advantage of livestock wastes

  19. Integrated strategic and tactical biomass-biofuel supply chain optimization.

    Science.gov (United States)

    Lin, Tao; Rodríguez, Luis F; Shastri, Yogendra N; Hansen, Alan C; Ting, K C

    2014-03-01

    To ensure effective biomass feedstock provision for large-scale biofuel production, an integrated biomass supply chain optimization model was developed to minimize annual biomass-ethanol production costs by optimizing both strategic and tactical planning decisions simultaneously. The mixed integer linear programming model optimizes the activities range from biomass harvesting, packing, in-field transportation, stacking, transportation, preprocessing, and storage, to ethanol production and distribution. The numbers, locations, and capacities of facilities as well as biomass and ethanol distribution patterns are key strategic decisions; while biomass production, delivery, and operating schedules and inventory monitoring are key tactical decisions. The model was implemented to study Miscanthus-ethanol supply chain in Illinois. The base case results showed unit Miscanthus-ethanol production costs were $0.72L(-1) of ethanol. Biorefinery related costs accounts for 62% of the total costs, followed by biomass procurement costs. Sensitivity analysis showed that a 50% reduction in biomass yield would increase unit production costs by 11%. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Multi-functional biomass systems

    NARCIS (Netherlands)

    Dornburg, Veronika

    2004-01-01

    Biomass can play a role in mitigating greenhouse gas emissions by substituting conventional materials and supplying biomass based fuels. Main reason for the low share of biomass applications in Europe is their often-high production costs, among others due to the relatively low availability of

  1. Biomass gasification in the Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Van der Drift, A. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2013-07-15

    This reports summarizes the activities, industries, and plants on biomass gasification in the Netherlands. Most of the initiatives somehow relate to waste streams, rather than clean biomass, which may seem logic for a densely populated country as the Netherlands. Furthermore, there is an increasing interest for the production of SNG (Substitute Natural Gas) from biomass, both from governments and industry.

  2. Optimal grid design and logistic planning for wind and biomass based renewable electricity supply chains under uncertainties

    International Nuclear Information System (INIS)

    Osmani, Atif; Zhang, Jun

    2014-01-01

    In this work, the grid design and optimal allocation of wind and biomass resources for renewable electricity supply chains under uncertainties is studied. Due to wind intermittency, generation of wind electricity is not uniform and cannot be counted on to be readily available to meet the demand. Biomass represents a type of stored energy and is the only renewable resource that can be used for producing biofuels and generating electricity whenever required. However, amount of biomass resources are finite and might not be sufficient to meet the demand for electricity and biofuels. Potential of wind and biomass resources is therefore jointly analyzed for electricity generation. Policies are proposed and evaluated for optimal allocation of finite biomass resources for electricity generation. A stochastic programming model is proposed that optimally balances the electricity demand across the available supply from wind and biomass resources under uncertainties in wind speed and electricity sale price. A case study set in the American Midwest is presented to demonstrate the effectiveness of the proposed model by determining the optimal decisions for generation and transmission of renewable electricity. Sensitivity analysis shows that level of subsidy for renewable electricity production has a major impact on the decisions. - Highlights: • Stochastic optimization model for wind/biomass renewable electricity supply chain. • Multiple uncertainties in wind speeds and electricity sale price. • Proposed stochastic model outperforms the deterministic model under uncertainties. • Uncertainty affects grid connectivity and allocation of power generation capacity. • Location of wind farms is found to be insensitive to the stochastic environment

  3. Bio-methane via fast pyrolysis of biomass

    International Nuclear Information System (INIS)

    Görling, Martin; Larsson, Mårten; Alvfors, Per

    2013-01-01

    Highlights: ► Pyrolysis gases can efficiently be upgraded to bio-methane. ► The integration can increase energy efficiency and provide a renewable vehicle fuel. ► The biomass to bio-methane conversion efficiency is 83% (HHV). ► The efficiency is higher compared to bio-methane produced via gasification. ► Competitive alternative to other alternatives of bio-oil upgrading. - Abstract: Bio-methane, a renewable vehicle fuel, is today produced by anaerobic digestion and a 2nd generation production route via gasification is under development. This paper proposes a poly-generation plant that produces bio-methane, bio-char and heat via fast pyrolysis of biomass. The energy and material flows for the fuel synthesis are calculated by process simulation in Aspen Plus®. The production of bio-methane and bio-char amounts to 15.5 MW and 3.7 MW, when the total inputs are 23 MW raw biomass and 1.39 MW electricity respectively (HHV basis). The results indicate an overall efficiency of 84% including high-temperature heat and the biomass to bio-methane yield amounts to 83% after allocation of the biomass input to the final products (HHV basis). The overall energy efficiency is higher for the suggested plant than for the gasification production route and is therefore a competitive route for bio-methane production

  4. High Pressure Biomass Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Agrawal, Pradeep K [Georgia Tech Research Corporation, Atlanta, GA (United States)

    2016-07-29

    According to the Billion Ton Report, the U.S. has a large supply of biomass available that can supplement fossil fuels for producing chemicals and transportation fuels. Agricultural waste, forest residue, and energy crops offer potential benefits: renewable feedstock, zero to low CO2 emissions depending on the specific source, and domestic supply availability. Biomass can be converted into chemicals and fuels using one of several approaches: (i) biological platform converts corn into ethanol by using depolymerization of cellulose to form sugars followed by fermentation, (ii) low-temperature pyrolysis to obtain bio-oils which must be treated to reduce oxygen content via HDO hydrodeoxygenation), and (iii) high temperature pyrolysis to produce syngas (CO + H2). This last approach consists of producing syngas using the thermal platform which can be used to produce a variety of chemicals and fuels. The goal of this project was to develop an improved understanding of the gasification of biomass at high pressure conditions and how various gasification parameters might affect the gasification behavior. Since most downstream applications of synags conversion (e.g., alcohol synthesis, Fischer-Tropsch synthesis etc) involve utilizing high pressure catalytic processes, there is an interest in carrying out the biomass gasification at high pressure which can potentially reduce the gasifier size and subsequent downstream cleaning processes. It is traditionally accepted that high pressure should increase the gasification rates (kinetic effect). There is also precedence from coal gasification literature from the 1970s that high pressure gasification would be a beneficial route to consider. Traditional approach of using thermogravimetric analyzer (TGA) or high-pressure themogravimetric analyzer (PTGA) worked well in understanding the gasification kinetics of coal gasification which was useful in designing high pressure coal gasification processes. However

  5. Biomass torrefaction: A promising pretreatment technology for biomass utilization

    Science.gov (United States)

    Chen, ZhiWen; Wang, Mingfeng; Ren, Yongzhi; Jiang, Enchen; Jiang, Yang; Li, Weizhen

    2018-02-01

    Torrefaction is an emerging technology also called mild pyrolysis, which has been explored for the pretreatment of biomass to make the biomass more favorable for further utilization. Dry torrefaction (DT) is a pretreatment of biomass in the absence of oxygen under atmospheric pressure and in a temperature range of 200-300 degrees C, while wet torrrefaction (WT) is a method in hydrothermal or hot and high pressure water at the tempertures within 180-260 degrees C. Torrrefied biomass is hydrophobic, with lower moisture contents, increased energy density and higher heating value, which are more comparable to the characteristics of coal. With the improvement in the properties, torrefied biomass mainly has three potential applications: combustion or co-firing, pelletization and gasification. Generally, the torrefaction technology can accelerate the development of biomass utilization technology and finally realize the maximum applications of biomass energy.

  6. Transnational Energy Companies' Investment Allocation Decisions

    Energy Technology Data Exchange (ETDEWEB)

    Osmundsen, Petter; Emhjellen, Magne; Halleraker, Morten

    2001-10-01

    When making international capital budgeting decisions, energy companies are often faced with capital and organisational constraints. The constraints may be real or management imposed. In addition, when entering into a new country or region the companies will incur fixed new area costs that must be considered before investment approval. The decision problem is therefore not a linear problem where the standard net present value rule applies, but a non-linear problem of selecting the combination of projects with the maximum aggregate net present value. New project investments will therefore be selected based on the size of the net present value (often referred to as financial volume or materiality) compared to the projects' use of capital and scarce personnel and organisational capacity. Consequently, projects with a positive net present value, but with low materiality, may not be approved. The portfolio choice has a parallel to the company's choice of core areas. Instead of complex portfolio models, the companies often apply simpler allocation mechanisms, e.g., combinations of fixed investment budgets and materiality requirements. Analysing petroleum cases, we compare the allocations decisions generated by portfolio models and simpler mechanisms. We also discuss the implications of this capital allocation pattern for governments' design of tax systems and license conditions. (author)

  7. Sex allocation promotes the stable co-occurrence of competitive species

    Science.gov (United States)

    Kobayashi, Kazuya

    2017-03-01

    Biodiversity has long been a source of wonder and scientific curiosity. Theoretically, the co-occurrence of competitive species requires niche differentiation, and such differences are well known; however, the neutral theory, which assumes the equivalence of all individuals regardless of the species in a biological community, has successfully recreated observed patterns of biodiversity. In this research, the evolution of sex allocation is demonstrated to be the key to resolving why the neutral theory works well, despite the observed species differences. The sex allocation theory predicts that female-biased allocation evolves in species in declining density and that this allocation improves population growth, which should lead to an increase in density. In contrast, when the density increases, a less biased allocation evolves, which reduces the population growth rate and leads to decreased density. Thus, sex allocation provides a buffer against species differences in population growth. A model incorporating this mechanism demonstrates that hundreds of species can co-occur over 10,000 generations, even in homogeneous environments, and reproduces the observed patterns of biodiversity. This study reveals the importance of evolutionary processes within species for the sustainability of biodiversity. Integrating the entire biological process, from genes to community, will open a new era of ecology.

  8. Solid biomass barometer

    International Nuclear Information System (INIS)

    Anon.

    2006-01-01

    The European (EU 25) wish to substitute solid biomass origin energy consumption (principally wood and wood waste, but also straw, crop harvest residues, vegetal and animal waste) for a part of that of fossil fuel origin (petrol, gas and coal) is beginning to pay off. 58,7 million tons oil equivalent (Mtoe) of solid biomass was produced in 2005, i.e. a 3.1 Mtoe increase with respect to 2004. Production of primary energy coming from direct combustion of renewable municipal solid waste in incineration plants should also be added on to this figure. The 0,2 Mtoe increase in this production with respect to 2004 brings valorization of this type of waste up to 5,3 Mtoe in 2005. (author)

  9. Spatial Allocator for air quality modeling

    Science.gov (United States)

    The Spatial Allocator is a set of tools that helps users manipulate and generate data files related to emissions and air quality modeling without requiring the use of a commercial Geographic Information System.

  10. U.S. Army Recruiter Allocation Model

    National Research Council Canada - National Science Library

    Brence, John

    2004-01-01

    .... Our methodology will build on both the new and old schools of recruiting by conducting stakeholder interviews that will lead us to a model that is an efficient starting point for the Recruiter Mission Allocation (RMA...

  11. Worst-case analysis of heap allocations

    DEFF Research Database (Denmark)

    Puffitsch, Wolfgang; Huber, Benedikt; Schoeberl, Martin

    2010-01-01

    In object oriented languages, dynamic memory allocation is a fundamental concept. When using such a language in hard real-time systems, it becomes important to bound both the worst-case execution time and the worst-case memory consumption. In this paper, we present an analysis to determine...... the worst-case heap allocations of tasks. The analysis builds upon techniques that are well established for worst-case execution time analysis. The difference is that the cost function is not the execution time of instructions in clock cycles, but the allocation in bytes. In contrast to worst-case execution...... time analysis, worst-case heap allocation analysis is not processor dependent. However, the cost function depends on the object layout of the runtime system. The analysis is evaluated with several real-time benchmarks to establish the usefulness of the analysis, and to compare the memory consumption...

  12. BIOMASS newsletter. No. 7

    International Nuclear Information System (INIS)

    Torres, Carlos

    1999-06-01

    The International Atomic Energy Agency Programme on Biosphere Modelling and Assessment (BIOMASS) Newsletter has been launched with general objectives of providing an international focal point in the area of biosphere assessment modelling, developing methods for analysis of radionuclide transfer in the biosphere for use in radiological assessment, improving modelling methods, and developing international consensus on biosphere modelling philosophies, approaches and parameter values. The main themes included in the Newsletter include radioactive waste disposal (reference biosphere), environmental releases and biosphere processes

  13. BIOMASS newsletter. No. 2

    International Nuclear Information System (INIS)

    Torres, Carlos

    1996-12-01

    The International Atomic Energy Agency Programme on Biosphere Modelling and Assessment (BIOMASS) Newsletter has been launched with general objectives of providing an international focal point in the area of biosphere assessment modelling, developing methods for analysis of radionuclide transfer in the biosphere for use in radiological assessment, improving modelling methods, and developing international consensus on biosphere modelling philosophies, approaches and parameter values. The main themes included in the Newsletter include radioactive waste disposal (reference biosphere), environmental releases and biosphere processes

  14. Biomass sustainability and certification.

    Science.gov (United States)

    Pavanan, Krishna C; Bosch, Roeland A; Cornelissen, Rob; Philp, Jim C

    2013-07-01

    The major challenges for humanity include energy security, food security, climate change, and a growing world population. They are all linked together by an instinctive, and yet increasingly complex and evolving concept, that of sustainability. Industrial biotechnology is seen as part of the overall solution, principally to combat climate change and strengthen energy security. At its beating heart is a huge policy challenge - the sustainability of biomass. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. BIOMASS newsletter. No. 6

    International Nuclear Information System (INIS)

    Torres, Carlos

    1999-01-01

    The International Atomic Energy Agency Programme on Biosphere Modelling and Assessment (BIOMASS) Newsletter has been launched with general objectives of providing an international focal point in the area of biosphere assessment modelling, developing methods for analysis of radionuclide transfer in the biosphere for use in radiological assessment, improving modelling methods, and developing international consensus on biosphere modelling philosophies, approaches and parameter values. The main themes included in the Newsletter include radioactive waste disposal (reference biosphere), environmental releases and biosphere processes

  16. BIOMASS newsletter. No. 8

    International Nuclear Information System (INIS)

    Torres, Carlos

    2000-01-01

    The International Atomic Energy Agency Programme on Biosphere Modelling and Assessment (BIOMASS) Newsletter has been launched with general objectives of providing an international focal point in the area of biosphere assessment modelling, developing methods for analysis of radionuclide transfer in the biosphere for use in radiological assessment, improving modelling methods, and developing international consensus on biosphere modelling philosophies, approaches and parameter values. The main themes included in the Newsletter include radioactive waste disposal (reference biosphere), environmental releases and biosphere processes

  17. Hydrothermal conversion of biomass

    Energy Technology Data Exchange (ETDEWEB)

    Knezevic, D.

    2009-09-03

    This thesis presents research of hydrothermal conversion of biomass (HTC). In this process, hot compressed water (subcritical water) is used as the reaction medium. Therefore this technique is suitable for conversion of wet biomass/ waste streams. By working at high pressures, the evaporation of water and high energy consumption that it requires can be avoided. The main focus of this work was HTC process aiming at production of transportation fuel intermediates. For this study, a new experimental technique using quartz capillary batch reactors has been developed, allowing determination of the yields of gas, liquid and solid products, and their subsequent analysis. The study was performed using glucose, a biomass model compound, and complex feedstocks, wood and pyrolysis oil. Important HTC features have been studied such as, undesired char formation, deoxygenation, and mechanism and kinetics of formation of different lumped product classes. Special attention is also given to products of the initial glucose decomposition and the kinetics of their formation. Complete mass and elemental balances obtained in this work significantly complement the literature findings on the reaction mechanism of HTC. Two distinct mechanisms of char formation are identified and two mechanisms of deoxygenation (dehydration and decarboxylation) are discussed. The observed trends in the product formation rates and yields are used to obtain an engineering reaction model for decomposition of glucose, which can be adapted for the use with complex feedstocks. Finally, a bench scale continuous reactor setup for HTC is proposed and several features of the setup have been tested separately in cold-flow, such as, feeding of biomass water slurries with a piston autoclave and a lifting fluidized bed, heat transfer, fluid bed operation and state of mixing of liquid and solid phases in continuous operations.

  18. Resource allocation criteria in a hospital

    OpenAIRE

    Bodina, A.; Pavan, A.; Castaldi, S.

    2017-01-01

    Summary Introduction. Allocate fixed resources among competing users is a challenge in terms of hospital management in order to obtain the best performance considering strategic objectives. In order to address this need, a system of evaluation in an important research and teaching hospital was designed. This study describes resource allocation criteria in a hospital focusing on the evaluation system and its developed application methodology. Methods. The indicator system allows the strategic ...

  19. Cost allocation. Combined heat and power production

    International Nuclear Information System (INIS)

    Sidzikauskas, V.

    2002-01-01

    The benefits of Combined Heat and Power (CHP) generation are discussed. The include improvement in energy intensity of 1% by 2010, 85-90% efficiency versus 40-50% of condensation power and others. Share of CHP electricity production in ERRA countries is presented.Solutions for a development CHP cost allocation are considered. Conclusion are presented for CHP production cost allocation. (R.P.)

  20. Macroeconomic Influences on Optimal Asset Allocation

    OpenAIRE

    Flavin, Thomas; Wickens, Michael R.

    2002-01-01

    We develop a tactical asset allocation strategy that incorporates the effects of macroeconomic variables. The joint distribution of financial asset returns and the macroeconomic variables is modelled using a VAR with a multivariate GARCH (M-GARCH) error structure. As a result, the portfolio frontier is time varying and subject to contagion from the macroeconomic variable. Optimal asset allocation requires that this be taken into account. We illustrate how to do this using three ri...

  1. Optimality versus stability in water resource allocation.

    Science.gov (United States)

    Read, Laura; Madani, Kaveh; Inanloo, Bahareh

    2014-01-15

    Water allocation is a growing concern in a developing world where limited resources like fresh water are in greater demand by more parties. Negotiations over allocations often involve multiple groups with disparate social, economic, and political status and needs, who are seeking a management solution for a wide range of demands. Optimization techniques for identifying the Pareto-optimal (social planner solution) to multi-criteria multi-participant problems are commonly implemented, although often reaching agreement for this solution is difficult. In negotiations with multiple-decision makers, parties who base decisions on individual rationality may find the social planner solution to be unfair, thus creating a need to evaluate the willingness to cooperate and practicality of a cooperative allocation solution, i.e., the solution's stability. This paper suggests seeking solutions for multi-participant resource allocation problems through an economics-based power index allocation method. This method can inform on allocation schemes that quantify a party's willingness to participate in a negotiation rather than opt for no agreement. Through comparison of the suggested method with a range of distance-based multi-criteria decision making rules, namely, least squares, MAXIMIN, MINIMAX, and compromise programming, this paper shows that optimality and stability can produce different allocation solutions. The mismatch between the socially-optimal alternative and the most stable alternative can potentially result in parties leaving the negotiation as they may be too dissatisfied with their resource share. This finding has important policy implications as it justifies why stakeholders may not accept the socially optimal solution in practice, and underlies the necessity of considering stability where it may be more appropriate to give up an unstable Pareto-optimal solution for an inferior stable one. Authors suggest assessing the stability of an allocation solution as an

  2. Discrete Tolerance Allocation for Product Families

    OpenAIRE

    2011-01-01

    Abstract This paper extends earlier research on the discrete tolerance allocation problem in order to optimize an entire product family simultaneously. This methodology enables top-down tolerancing approach where requirements on assembly level on products within a family are allocated to single part requirements. The proposed solution has been implemented as an interface with an optimization algorithm coupled with a variation simulation software. The paper also consists of an exten...

  3. Ethanol from lignocellulosic biomasses

    International Nuclear Information System (INIS)

    Ricci, E.; Viola, E.; Zimbardi, F.; Braccio, G.; Cuna, D.

    2001-01-01

    In this report are presented results achieved on the process optimisation of bioethanol production from wheat straw, carried out within the ENEA's project of biomass exploitation for renewable energy. The process consists of three main steps: 1) biomass pretreatment by means of steam explosion; 2) enzymatic hydrolysis of the cellulose fraction; 3) fermentation of glucose. To perform the hydrolysis step, two commercial enzymatic mixtures have been employed, mainly composed by β-glucosidase (cellobiase), endo-glucanase and exo-glucanase. The ethanologenic yeast Saccharomyces cerevisiae has been used to ferment the glucose in he hydrolyzates. Hydrolysis yield of 97% has been obtained with steam exploded wheat straw treated at 220 0 C for 3 minutes and an enzyme to substrate ratio of 4%. It has been pointed out the necessity of washing with water the pretreated what straw, in order to remove the biomass degradation products, which have shown an inhibition effect on the yeast. At the best process conditions, a fermentation yield of 95% has been achieved. In the Simultaneous Saccharification and Fermentation process, a global conversion of 92% has been obtained, which corresponds to the production of about 170 grams of ethanol per kilogram of exploded straw [it

  4. Hydrolysis of biomass material

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Andrew J.; Orth, Rick J.; Franz, James A.; Alnajjar, Mikhail

    2004-02-17

    A method for selective hydrolysis of the hemicellulose component of a biomass material. The selective hydrolysis produces water-soluble small molecules, particularly monosaccharides. One embodiment includes solubilizing at least a portion of the hemicellulose and subsequently hydrolyzing the solubilized hemicellulose to produce at least one monosaccharide. A second embodiment includes solubilizing at least a portion of the hemicellulose and subsequently enzymatically hydrolyzing the solubilized hemicellulose to produce at least one monosaccharide. A third embodiment includes solubilizing at least a portion of the hemicellulose by heating the biomass material to greater than 110.degree. C. resulting in an aqueous portion that includes the solubilized hemicellulose and a water insoluble solids portion and subsequently separating the aqueous portion from the water insoluble solids portion. A fourth embodiment is a method for making a composition that includes cellulose, at least one protein and less than about 30 weight % hemicellulose, the method including solubilizing at least a portion of hemicellulose present in a biomass material that also includes cellulose and at least one protein and subsequently separating the solubilized hemicellulose from the cellulose and at least one protein.

  5. Effect of different crop management systems on net primary productivity and relative carbon allocation coefficients for corn (Zea mays L.

    Directory of Open Access Journals (Sweden)

    S. Khorramdel

    2016-04-01

    Full Text Available In order to evaluate the effect of different crop management practices on corn (Zea mays L. net primary productivity (NPP and relative carbon allocation coefficients, a field experiment was conducted based on a completely randomized block design with four replications in the Agricultural Research Station, Ferdowsi University of Mashhad, Iran during two growing season 2008-2009 and 2009-2010. Treatments including two low input management systems based on application of cow manure and compost municipal made from house-hold waste, a medium input system and a high input system. Application of inputs and management practices were based on a basic assumption made prior to the start of the experiment. On the other words, for each of the management system the particular set of inputs were allocated. In this respect, for low input system 30 t.ha-1 cow manure or 30 t.ha-1 compost municipal made from house-hold waste, twice hand weeding were used. In medium management system, 15 t.ha-1 compost municipal made from house-hold waste, 150 kg.ha-1 urea, two seed bed operations, 1.5 l.ha-1 2, 4-D herbicide applied at five-leaf stage and one time hand weeding were used. In high input system, the inputs were two seed bed operations, 2 l.ha-1 Paraquat herbicide used after seeding and 1.5 l.ha-1 2, 4-D applied at five-leaf stage. Results showed that the effect of different crop management practices on the shoot biomass, seed weight, root biomass, total biomass, shoot biomass: root biomass (S:R, SRL and HI were significant (p≥0.01. High input management system enhanced total biomass and S:R and decreased seed weight, root biomass and SRL. The highest and the lowest total biomass observed in high input (18.3 kg.m-2.yr-1 and low input with using compost (10.3 kg.m-2.yr-1, respectively. The maximum SRL observed in low input based on cow manure application (19.8 cm.cm-3 soil and the minimum SRL was in high input (1.3 cm.cm-3 soil. Range of relative carbon allocation

  6. Revenue Allocation and Economic Development in Nigeria

    Directory of Open Access Journals (Sweden)

    Dagwom Yohanna Dang

    2013-09-01

    Full Text Available This study empirically examines the impact of revenue allocation on economic development in Nigeria. Specifically, the study looks at how the various revenue allocations to the three tiers of government affect real gross domestic product (RGDP in Nigeria using time series data for the period 1993 to 2012. Error correction model (ECM and Pairwise Granger Causality test are used in analyzing the data. The study carries out test of stationarity of the variables using Augmented Dickey–Fuller unit root test and test of long-run relationship among the variables using Johansen Cointegration test. The study’s findings show that revenue allocations have significant causal relationship with economic development in Nigeria, with only revenue allocation to states having significant negative relationship. Unidirectional causality runs from revenue allocations to real GDP in Nigeria. All variables of the study are cointegrated and have a long-run relationship that 87.62% of the short-run disequilibrium is corrected yearly. The study recommends among others that more financial control and value for money audit should be carried out to minimize wastages and corruption in the states of the federation, so as to change the direction of influence of states’ revenue allocation on economic development.

  7. The enigma of sex allocation in Selaginella.

    Science.gov (United States)

    Petersen, Kurt B; Burd, Martin

    2018-02-12

    The division of resource investment between male and female functions is poorly known for land plants other than angiosperms. The ancient lycophyte genus Selaginella is similar in some ways to angiosperms (in heterospory and in having sex allocation occur in the sporophyte generation, for example) but lacks the post-fertilization maternal investments that angiosperms make via fruit and seed tissues. One would therefore expect Selaginella to have sex allocation values less female-biased than in flowering plants and closer to the theoretical prediction of equal investment in male and female functions. Nothing is currently known of sex allocation in the genus, so even the simplest predictions have not been tested. Volumetric measurements of microsporangial and megasporangial investment were made in 14 species of Selaginella from four continents. In five of these species the length of the main above-ground axis of each plant was measured to determine whether sex allocation is related to plant size. Of the 14 species, 13 showed male-biased allocations, often extreme, in population means and among the great majority of individual plants. There was some indication from the five species with axis length measurements that relative male allocation might be related to the release height of spores, but this evidence is preliminary. Sex allocation in Selaginella provides a phylogenetic touchstone showing how the innovations of fruit and seed investment in the angiosperm life cycle lead to typically female-biased allocations in that lineage. Moreover, the male bias we found in Selaginella requires an evolutionary explanation. The bias was often greater than what would occur from the mere absence of seed and fruit investments, and thus poses a challenge to sex allocation theory. It is possible that differences between microspores and megaspores in their dispersal ecology create selective effects that favour male-biased sexual allocation. This hypothesis remains tentative. © The

  8. Transportation Energy Futures Series. Projected Biomass Utilization for Fuels and Power in a Mature Market

    Energy Technology Data Exchange (ETDEWEB)

    Ruth, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mai, T. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Newes, E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Aden, A. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Warner, E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Uriarte, C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Inman, D. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Simpkins, T. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Argo, A. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2013-03-01

    The viability of biomass as transportation fuel depends upon the allocation of limited resources for fuel, power, and products. By focusing on mature markets, this report identifies how biomass is projected to be most economically used in the long term and the implications for greenhouse gas (GHG) emissions and petroleum use. In order to better understand competition for biomass between these markets and the potential for biofuel as a market-scale alternative to petroleum-based fuels, this report presents results of a micro-economic analysis conducted using the Biomass Allocation and Supply Equilibrium (BASE) modeling tool. The findings indicate that biofuels can outcompete biopower for feedstocks in mature markets if research and development targets are met. The BASE tool was developed for this project to analyze the impact of multiple biomass demand areas on mature energy markets. The model includes domestic supply curves for lignocellulosic biomass resources, corn for ethanol and butanol production, soybeans for biodiesel, and algae for diesel. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  9. Transportation Energy Futures Series: Projected Biomass Utilization for Fuels and Power in a Mature Market

    Energy Technology Data Exchange (ETDEWEB)

    Ruth, M.; Mai, T.; Newes, E.; Aden, A.; Warner, E.; Uriarte, C.; Inman, D.; Simpkins, T.; Argo, A.

    2013-03-01

    The viability of biomass as transportation fuel depends upon the allocation of limited resources for fuel, power, and products. By focusing on mature markets, this report identifies how biomass is projected to be most economically used in the long term and the implications for greenhouse gas (GHG) emissions and petroleum use. In order to better understand competition for biomass between these markets and the potential for biofuel as a market-scale alternative to petroleum-based fuels, this report presents results of a micro-economic analysis conducted using the Biomass Allocation and Supply Equilibrium (BASE) modeling tool. The findings indicate that biofuels can outcompete biopower for feedstocks in mature markets if research and development targets are met. The BASE tool was developed for this project to analyze the impact of multiple biomass demand areas on mature energy markets. The model includes domestic supply curves for lignocellulosic biomass resources, corn for ethanol and butanol production, soybeans for biodiesel, and algae for diesel. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  10. Biomass to energy; La valorisation energetique de la biomasse

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-06-15

    This road-map proposes by the Group Total aims to inform the public on the biomass to energy. It explains the biomass principle, the possibility of biomass to energy conversion, the first generation of biofuels (bio ethanol, ETBE, bio diesel, flex fuel) and their advantages and limitations, the european regulatory framework and policy with the evolutions and Total commitments in the domain. (A.L.B.)

  11. Unearthing the hidden world of roots: Root biomass and architecture differ among species within the same guild.

    Science.gov (United States)

    Sinacore, Katherine; Hall, Jefferson Scott; Potvin, Catherine; Royo, Alejandro A; Ducey, Mark J; Ashton, Mark S

    2017-01-01

    The potential benefits of planting trees have generated significant interest with respect to sequestering carbon and restoring other forest based ecosystem services. Reliable estimates of carbon stocks are pivotal for understanding the global carbon balance and for promoting initiatives to mitigate CO2 emissions through forest management. There are numerous studies employing allometric regression models that convert inventory into aboveground biomass (AGB) and carbon (C). Yet the majority of allometric regression models do not consider the root system nor do these equations provide detail on the architecture and shape of different species. The root system is a vital piece toward understanding the hidden form and function roots play in carbon accumulation, nutrient and plant water uptake, and groundwater infiltration. Work that estimates C in forests as well as models that are used to better understand the hydrologic function of trees need better characterization of tree roots. We harvested 40 trees of six different species, including their roots down to 2 mm in diameter and created species-specific and multi-species models to calculate aboveground (AGB), coarse root belowground biomass (BGB), and total biomass (TB). We also explore the relationship between crown structure and root structure. We found that BGB contributes ~27.6% of a tree's TB, lateral roots extend over 1.25 times the distance of crown extent, root allocation patterns varied among species, and that AGB is a strong predictor of TB. These findings highlight the potential importance of including the root system in C estimates and lend important insights into the function roots play in water cycling.

  12. Unearthing the hidden world of roots: Root biomass and architecture differ among species within the same guild.

    Directory of Open Access Journals (Sweden)

    Katherine Sinacore

    Full Text Available The potential benefits of planting trees have generated significant interest with respect to sequestering carbon and restoring other forest based ecosystem services. Reliable estimates of carbon stocks are pivotal for understanding the global carbon balance and for promoting initiatives to mitigate CO2 emissions through forest management. There are numerous studies employing allometric regression models that convert inventory into aboveground biomass (AGB and carbon (C. Yet the majority of allometric regression models do not consider the root system nor do these equations provide detail on the architecture and shape of different species. The root system is a vital piece toward understanding the hidden form and function roots play in carbon accumulation, nutrient and plant water uptake, and groundwater infiltration. Work that estimates C in forests as well as models that are used to better understand the hydrologic function of trees need better characterization of tree roots. We harvested 40 trees of six different species, including their roots down to 2 mm in diameter and created species-specific and multi-species models to calculate aboveground (AGB, coarse root belowground biomass (BGB, and total biomass (TB. We also explore the relationship between crown structure and root structure. We found that BGB contributes ~27.6% of a tree's TB, lateral roots extend over 1.25 times the distance of crown extent, root allocation patterns varied among species, and that AGB is a strong predictor of TB. These findings highlight the potential importance of including the root system in C estimates and lend important insights into the function roots play in water cycling.

  13. Coexistence and environmental filtering of species-specific biomass in an African savanna.

    Science.gov (United States)

    Colgan, Matthew S; Asner, Gregory P

    2014-06-01

    Biomass density is a key metric of vegetation abundance, but understanding how community assembly processes, such as environmental filtering and competitive exclusion, affect biomass distributions of coexisting species has proven logistically challenging. Here we apply airborne remote sensing to study the ecosystem-scale distribution of species-specific, woody plant biomass and its relation to topographic and hydrologic gradients in a South African savanna. We also spatially analyzed variation in biomass among species to understand patterns of coexistence, mapping the species and biomass over one million trees across 10500 ha. We found the biomass of dominant woody species to be weakly but significantly related to environmental filters, where a combination of 10 topographic and edaphic variables accounted for community assembly processes in natural ecosystems. Characterizing the species composition of biomass is an important advance in understanding the balance of community assembly processes and its control over current species assemblages.

  14. BAAD: a biomass and allometry database for woody plants

    Science.gov (United States)

    Daniel S. Falster; Remko A. Duursma; Masae I. Ishihara; Diego R. Barneche; Richard G. FitzJohn; Angelica Varhammar; Masahiro Aiba; Makoto Ando; Niels Anten; Michael J. Aspinwall; Jennifer L. Baltzer; Christopher Baraloto; Michael Battaglia; John J. Battles; Ben Bond-Lamberty; Michiel van Breugel; Yves Claveau; Masako Dannoura; Sylvain Delagrange; Jean-Christophe Domec; Farrah Fatemi; Wang Feng; Veronica Gargaglione; Yoshiaki Goto; Akio Hagihara; Jefferson S. Hall; Steve Hamilton; Degi Harja; Tsutom Hiura; Robert Holdaway; Lindsay S. Hutley; Tomoaki Ichie; Eric J. Jokela; Anu Kantola; Jeff W. G. Kelly; Tanaka Kenzo; David King; Brian D. Kloeppel; Takashi Kohyama; Akira Komiyama; Jean-Paul Laclau; Christopher H. Lusk; Douglas A. Maguire; Guerric Le Maire; Ammikki Makela; Lars Markesteijn; John Marshall; Katherine McCulloh; Itsuo Miyata; Karel Mokany; Shugeta Mori; Randall W. Myster; Masahiro Nagano; Shawna L. Naidu; Yann Nouvellon; Anthony P. O' Grady; Kevin L. O' Hara; Toshiyuki Ohtsuka; Noriyuki Osada; Olusegun O. Osunkoya; Pablo Luis Peri; Any Mary Petritan; Lourens Poorter; Angelika Portsmuth; Catherine Potvin; Johannes Ransijn; Douglas Reid; Sabina C. Ribeiro; Scott D. Roberts; Rolando Rodriguez; Angela Saldana-Acosta; Ignacio Santa-Regina; Kaichiro Sasa; N. Galia Selaya; Stephen C. Sillett; Frank Sterck; Kentaro Takagi; Takeshi Tange; Hiroyuki Tanouchi; David Tissue; Toru Umehara; Matthew A. Vadeboncoeur; Fernando Valladares; Petteri Vanninen; Jian R. Wang; Elizabeth Wenk; Richard Williams; Fabiano de Aquino Ximenes; Atsushi Yamaba; Toshihiro Yamada; Takuo Yamakura; Ruth D. Yanai; Robert A. York

    2015-01-01

    Understanding how plants are constructed—i.e., how key size dimensions and the amount of mass invested in different tissues varies among individuals—is essential for modeling plant growth, carbon stocks, and energy fluxes in the terrestrial biosphere. Allocation patterns can differ through ontogeny, but also among coexisting species and among species adapted to...

  15. Allocation of biomass resources for minimising energy system greenhouse gas emissions

    DEFF Research Database (Denmark)

    Bentsen, Niclas Scott; Felby, Claus; Jack, Michael W.

    2014-01-01

    The rhythmically bedded limestone–marl alternations in the coastal cliffs of Sopelana and Zumaia in the Basque country, northern Spain, permit testing and refining of existing Maastrichtian chronologies (latest Cretaceous). The recently established astronomical time scale for the late Maastrichti...

  16. Assessing wheat yield, Biomass, and water productivity responses to growth stage based irrigation water allocation

    Science.gov (United States)

    Increasing irrigated wheat yields is important to the overall profitability of limited-irrigation cropping systems in western Kansas. A simulation study was conducted to (1) validate APSIM's (Agricultural Production Systems sIMulator) ability to simulate wheat growth and yield in Kansas, and (2) app...

  17. Life history strategies and biomass allocation : the population dynamics of perennial plants in a regional perspective

    NARCIS (Netherlands)

    Jongejans, E.

    2004-01-01

    This study aims to contribute to the knowledge of how plants respond to adverse influences of intensified land use. In particular, attention was paid to the ways in which life history strategies change in order to buffer environmental variation, and which important parts of the life cycle are

  18. Introduction history influences aboveground biomass allocation in Brazilian peppertree (Schinus terebinthifolius)

    Science.gov (United States)

    Multiple introductions of an exotic species can facilitate invasion success by allowing for a wider range of expressed trait values in the adventive range. Brazilian peppertree is an invasive shrub that was introduced into Florida multiple times and has subsequently hybridized, resulting in three di...

  19. Plant–soil feedback induces shifts in biomass allocation in the invasive plant Chromolaena odorata

    CSIR Research Space (South Africa)

    Te Beest, M

    2009-09-01

    Full Text Available in non-native-range soil in con- and heterospecific soils. The mechanisms through which C. odora- ta interacts with the soil community are still to be clarified. Previous studies have shown that pyrrolizidine alkaloids are present in roots of...,M., Witte, L. & Hartmann, T. (1994) Pyrrolizidine alkaloids in Chromolaena odorata ? chemical and chemoecological aspects. Phyto- chemistry, 35, 615?619. Blossey, B. & No?tzold, R. (1995) Evolution of increased competitive ability in invasive...

  20. Ecosystems and biomass energy

    International Nuclear Information System (INIS)

    Trossero, M.A.

    1995-01-01

    Biomass, particularly fuelwood and charcoal, is one of the main sources of fuel to meet the energy needs of traditional, commercial and industrial activities in developing countries. While it satisfies only about 14% of the world's primary energy needs, in some countries it satisfies up to 80% of those needs. As a result of population growth, urbanization, economic reforms, restructuring and new development targets in most of these countries, new forms of energy and a more intensive use of energy are expected for the years ahead. This additional demand for energy will be met mainly by hydroelectricity, coal and fossil fuels. However, where biomass is available or can be planted, bio fuels can be converted into new forms of energy (electricity and power) and energy carriers (liquid and gaseous fuels) to meet not only the energy needs of the modem sectors but also to maintain a sustainable supply to traditional users. In fact, FAO estimates that biomass could provide nearly three times more energy than it does without affecting the current supply of other commodities and goods such as food, fodder, fuel, timber and non-wood fuel products. The benefits derived from the utilization of biomass as a source of energy are twofold: (a) the task of supplying bio fuels can help to attract new investment, create new employment and income opportunities in rural areas, raise the value of natural resources and preserve the environment and (b) new forms of energy and energy carriers could foster increased production and productivity at the rural and community level, particularly in remote areas where conventional fuels are not easily available at affordable prices. Bioenergy can be easily developed in modular and decentralized schemes and offers many advantages. It could be an inexpensive source of energy, even at present energy prices, and it requires less capital investment for its implementation than alternative solutions. However, there are many disadvantages, too. For

  1. Hydrothermal Liquefaction of Biomass

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Douglas C.

    2010-12-10

    Hydrothermal liquefaction technology is describes in its relationship to fast pyrolysis of biomass. The scope of work at PNNL is discussed and some intial results are presented. HydroThermal Liquefaction (HTL), called high-pressure liquefaction in earlier years, is an alternative process for conversion of biomass into liquid products. Some experts consider it to be pyrolysis in solvent phase. It is typically performed at about 350 C and 200 atm pressure such that the water carrier for biomass slurry is maintained in a liquid phase, i.e. below super-critical conditions. In some applications catalysts and/or reducing gases have been added to the system with the expectation of producing higher yields of higher quality products. Slurry agents ('carriers') evaluated have included water, various hydrocarbon oils and recycled bio-oil. High-pressure pumping of biomass slurry has been a major limitation in the process development. Process research in this field faded away in the 1990s except for the HydroThermal Upgrading (HTU) effort in the Netherlands, but has new resurgence with other renewable fuels in light of the increased oil prices and climate change concerns. Research restarted at Pacific Northwest National Laboratory (PNNL) in 2007 with a project, 'HydroThermal Liquefaction of Agricultural and Biorefinery Residues' with partners Archer-Daniels-Midland Company and ConocoPhillips. Through bench-scale experimentation in a continuous-flow system this project investigated the bio-oil yield and quality that could be achieved from a range of biomass feedstocks and derivatives. The project was completed earlier this year with the issuance of the final report. HydroThermal Liquefaction research continues within the National Advanced Biofuels Consortium with the effort focused at PNNL. The bench-scale reactor is being used for conversion of lignocellulosic biomass including pine forest residue and corn stover. A complementary project is an international

  2. Biomass process handbook

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    Descriptions are given of 42 processes which use biomass to produce chemical products. Marketing and economic background, process description, flow sheets, costs, major equipment, and availability of technology are given for each of the 42 processes. Some of the chemicals discussed are: ethanol, ethylene, acetaldehyde, butanol, butadiene, acetone, citric acid, gluconates, itaconic acid, lactic acid, xanthan gum, sorbitol, starch polymers, fatty acids, fatty alcohols, glycerol, soap, azelaic acid, perlargonic acid, nylon-11, jojoba oil, furfural, furfural alcohol, tetrahydrofuran, cellulose polymers, products from pulping wastes, and methane. Processes include acid hydrolysis, enzymatic hydrolysis, fermentation, distillation, Purox process, and anaerobic digestion.

  3. Biomass Energy Generation Project

    Energy Technology Data Exchange (ETDEWEB)

    Olthoff, Edward [Cedar Falls Utilities, Cedar Falls, IA (United States)

    2017-05-15

    The Municipal Electric Utility of the City of Cedar Falls (dba Cedar Fals Utilities or CFU) received a congressionally directed grant funded through DOE-EERE to run three short (4 hour) duration test burns and one long (10 days) duration test burn to test the viability of renewable fuels in Streeter Station Boiler #6, a stoker coal fired electric generation unit. The long test burn was intended to test supply chain assumptions, optimize boiler combustion and assess the effects of a longer duration burn of biomass on the boiler.

  4. SOME NOTES ON COST ALLOCATION IN MULTICASTING

    Directory of Open Access Journals (Sweden)

    Darko Skorin-Kapov

    2012-12-01

    Full Text Available We analyze the cost allocation strategies with the problef of broadcasting information from some source to a number of communication network users. A multicast routing chooses a minimum cost tree network that spans the source and all the receivers. The cost of such a network is distributed among its receivers who may be individuals or organizations with possibly conflicting interests. Providing network developers, users and owners with practical computable 'fair' cost allocation solution procedures is of great importance for network mamagement. Consequently, this multidisciplinary problem was extensively studied by Operational Researchers, Economists, Mathematicians and Computer Scientists. The fairness of various proposed solutions was even argued in US courts. This presentation overviews some previously published, as well as some recent results, in the development of algorithmic mechanisms to efficiently compute 'attractive' cost allocation solutions for multicast networks. Specifically, we will analyze cooperative game theory based cost allocation models that avoid cross subsidies and/or are distance and population monotonic. We will also present some related open cost allocation problems and the potential contribution that such models might make to this problem in the future.

  5. Methodology for allocating reliability and risk

    International Nuclear Information System (INIS)

    Cho, N.Z.; Papazoglou, I.A.; Bari, R.A.

    1986-05-01

    This report describes a methodology for reliability and risk allocation in nuclear power plants. The work investigates the technical feasibility of allocating reliability and risk, which are expressed in a set of global safety criteria and which may not necessarily be rigid, to various reactor systems, subsystems, components, operations, and structures in a consistent manner. The report also provides general discussions on the problem of reliability and risk allocation. The problem is formulated as a multiattribute decision analysis paradigm. The work mainly addresses the first two steps of a typical decision analysis, i.e., (1) identifying alternatives, and (2) generating information on outcomes of the alternatives, by performing a multiobjective optimization on a PRA model and reliability cost functions. The multiobjective optimization serves as the guiding principle to reliability and risk allocation. The concept of ''noninferiority'' is used in the multiobjective optimization problem. Finding the noninferior solution set is the main theme of the current approach. The final step of decision analysis, i.e., assessment of the decision maker's preferences could then be performed more easily on the noninferior solution set. Some results of the methodology applications to a nontrivial risk model are provided, and several outstanding issues such as generic allocation, preference assessment, and uncertainty are discussed. 29 refs., 44 figs., 39 tabs

  6. Risk capital allocation with autonomous subunits

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Smilgins, Aleksandrs

    2016-01-01

    Risk capital allocation problems have been widely discussed in the academic literature. We consider a set of independent subunits collaborating in order to reduce risk: that is, when subunit portfolios are merged a diversification benefit arises and the risk of the group as a whole is smaller tha...... fairness tests related directly to the problem of risk capital allocation and show that the Lorenz set satisfies all three tests in contrast to other well-known coherent methods. Finally, we discuss how to deal with non-uniqueness of the Lorenz set.......Risk capital allocation problems have been widely discussed in the academic literature. We consider a set of independent subunits collaborating in order to reduce risk: that is, when subunit portfolios are merged a diversification benefit arises and the risk of the group as a whole is smaller than...... the sum of the risks of the individual subunits. The question is how to allocate the risk capital of the group among the subunits in a fair way. In this paper we propose to use the Lorenz set as an allocation method. We show that the Lorenz set is operational and coherent. Moreover, we propose three...

  7. Cognitive allocation and the control room

    International Nuclear Information System (INIS)

    Paradies, M.W.

    1985-01-01

    One of the weakest links in the design of nuclear power plants is the inattention to the needs and capabilities of the operators. This flaw causes decreased plant reliability and reduced plant safety. To solve this problem the designer must, in the earliest stages of the design process, consider the operator's abilities. After the system requirements have been established, the designer must consider what functions to allocate to each part of the system. The human must be considered as part of this system. The allocation of functions needs to consider not only the mechanical tasks to be performed, but also the control requirements and the overall control philosophy. In order for the designers to consider the control philosophy, they need to know what control decisions should be automated and what decisions should be made by an operator. They also need to know how these decisions will be implemented: by an operator or by automation. ''Cognitive Allocation'' is the allocation of the decision making process between operators and machines. It defines the operator's role in the system. When designing a power plant, a cognitive allocation starts the process of considering the operator's abilities. This is the first step to correcting the weakest link in the current plant design

  8. Methanol from biomass and hydrogen

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    For Hawaii in the near term, the only liquid fuels indigenous sources will be those that can be made from biomass, and of these, methanol is the most promising. In addition, hydrogen produced by electrolysis can be used to markedly increase the yield of biomass methanol. This paper calculates cost of producing methanol by an integrated system including a geothermal electricity facility plus a plant producing methanol by gasifying biomass and adding hydrogen produced by electrolysis. Other studies cover methanol from biomass without added hydrogen and methanol from biomass by steam and carbon dioxide reforming. Methanol is made in a two-step process: the first is the gasification of biomass by partial oxidation with pure oxygen to produce carbon oxides and hydrogen, and the second is the reaction of gases to form methanol. Geothermal steam is used to generate the electricity used for the electrolysis to produce the added hydrogen

  9. A Spatial Model of the Biomass to Energy Cycle

    DEFF Research Database (Denmark)

    Möller, Bernd

    2003-01-01

    by location. This paper aims to contribute to the development of a biomass to energy evaluation and mapping system, using geographical information systems (GIS). A GIS-based in-forest residue model considers forest growth and choice of harvest method. Data from a sawmill survey is used to assess sawmill resi......-dues. For both sources the costs of road transportation have been modelled using spatial cost allocation. As emphasis has been on using public data, the model is still a rough es-timate, which could be improved using forest industry data and refined algorithms. As a first result, the cost distribution...... and the costs of accumulated amounts of wood residues can now be calculated almost instantly for each location in the country. It is assumed that this approach will facilitate the assessment of future biomass markets....

  10. Energy Recovery from Contaminated Biomass

    Directory of Open Access Journals (Sweden)

    Jiří Moskalík

    2012-01-01

    Full Text Available This study focuses on thermal gasification methods of contaminated biomass in an atmospheric fluidized bed, especially biomass contaminated by undesirable substances in its primary use. For the experiments, chipboard waste was chosen as a representative sample of contaminated biomass. In the experiments, samples of gas and tar were taken for a better description of the process of gasifying chipboard waste. Gas and tar samples also provide information about the properties of the gas that is produced.

  11. Ash Properties of Alternative Biomass

    DEFF Research Database (Denmark)

    Capablo, Joaquin; Jensen, Peter Arendt; Pedersen, Kim Hougaard

    2009-01-01

    analysis into three main groups depending upon their ash content of silica, alkali metal, and calcium and magnesium. To further detail the biomass classification, the relative molar ratio of Cl, S, and P to alkali were included. The study has led to knowledge on biomass fuel ash composition influence...... on ash transformation, ash deposit flux, and deposit chlorine content when biomass fuels are applied for suspension combustion....

  12. Biomass in Latin America -- overview

    International Nuclear Information System (INIS)

    Park, W.R.

    1993-01-01

    The paper discusses the interest of the Organization of American States as a participant in this hemispheric conference on biomass, provides an introduction to the Latin American experience in biomass energy through open-quotes snapshotsclose quotes of various country activities, and concludes with a discussion of four conditions that form strong incentives for new north/south and south/north ventures in the biomass energy and chemical arena in this hemisphere

  13. Integration of biomass into urban energy systems for heat and power. Part II: Sensitivity assessment of main techno-economic factors

    International Nuclear Information System (INIS)

    Pantaleo, Antonio M.; Giarola, Sara; Bauen, Ausilio; Shah, Nilay

    2014-01-01

    Highlights: • Application of a MILP tool for optimal sizing and location of heating and CHP plants to serve residential energy demand. • Trade-offs between local vs centralized heat generation, district heating vs natural gas distribution systems. • Assessment of the key factors influencing the use of biomass and district heating in residential areas. - Abstract: The paper presents the application of a mixed integer linear programming (MILP) methodology to optimize multi-biomass and natural gas supply chain strategic design for heat and power generation in urban areas. The focus is on spatial and temporal allocation of biomass supply, storage, processing, transport and energy conversion (heat and CHP) to match the heat demand of residential end users. The main aim lies on the assessment of the trade-offs between centralized district heating plants and local heat generation systems, and on the decoupling of the biomass processing and biofuel energy conversion steps. After a brief description of the methodology, which is presented in detail in Part I of the research, an application to a generic urban area is proposed. Moreover, the influence of energy demand typologies (urban areas energy density, heat consumption patterns, buildings energy efficiency levels, baseline energy costs and available infrastructures) and specific constraints of urban areas (transport logistics, air emission levels, space availability) on the selection of optimal bioenergy pathways for heat and power is assessed, by means of sensitivity analysis. On the basis of these results, broad considerations about the key factors influencing the use of bioenergy into urban energy systems are proposed. Potential further applications of this model are also described, together with main barriers for development of bioenergy routes for urban areas

  14. A bottom-up approach of stochastic demand allocation in water quality modelling

    NARCIS (Netherlands)

    Blokker, E.J.M.; Vreeburg, J.H.G.; Beverloo, H.; Klein Arfman, M.; Van Dijk, J.C.

    2010-01-01

    An “all pipes” hydraulic model of a DMA-sized drinking water distribution system was onstructed with two types of demand allocations. One is constructed with the conventional op-down approach, i.e. a demand multiplier pattern from the booster station is llocated to all demand nodes with a correction

  15. A hybrid model for mapping relative differences in belowground biomass and root: Shoot ratios using spectral reflectance, foliar N and plant biophysical data within coastal marsh

    Science.gov (United States)

    Jessica L. O'Connell,; Byrd, Kristin B.; Maggi Kelly,

    2015-01-01

    Broad-scale estimates of belowground biomass are needed to understand wetland resiliency and C and N cycling, but these estimates are difficult to obtain because root:shoot ratios vary considerably both within and between species. We used remotely-sensed estimates of two aboveground plant characteristics, aboveground biomass and % foliar N to explore biomass allocation in low diversity freshwater impounded peatlands (Sacramento-San Joaquin River Delta, CA, USA). We developed a hybrid modeling approach to relate remotely-sensed estimates of % foliar N (a surrogate for environmental N and plant available nutrients) and aboveground biomass to field-measured belowground biomass for species specific and mixed species models. We estimated up to 90% of variation in foliar N concentration using partial least squares (PLS) regression of full-spectrum field spectrometer reflectance data. Landsat 7 reflectance data explained up to 70% of % foliar N and 67% of aboveground biomass. Spectrally estimated foliar N or aboveground biomass had negative relationships with belowground biomass and root:shoot ratio in both Schoenoplectus acutus and Typha, consistent with a balanced growth model, which suggests plants only allocate growth belowground when additional nutrients are necessary to support shoot development. Hybrid models explained up to 76% of variation in belowground biomass and 86% of variation in root:shoot ratio. Our modeling approach provides a method for developing maps of spatial variation in wetland belowground biomass.

  16. A Hybrid Model for Mapping Relative Differences in Belowground Biomass and Root:Shoot Ratios Using Spectral Reflectance, Foliar N and Plant Biophysical Data within Coastal Marsh

    Directory of Open Access Journals (Sweden)

    Jessica L. O’Connell

    2015-12-01

    Full Text Available Broad-scale estimates of belowground biomass are needed to understand wetland resiliency and C and N cycling, but these estimates are difficult to obtain because root:shoot ratios vary considerably both within and between species. We used remotely-sensed estimates of two aboveground plant characteristics, aboveground biomass and % foliar N to explore biomass allocation in low diversity freshwater impounded peatlands (Sacramento-San Joaquin River Delta, CA, USA. We developed a hybrid modeling approach to relate remotely-sensed estimates of % foliar N (a surrogate for environmental N and plant available nutrients and aboveground biomass to field-measured belowground biomass for species specific and mixed species models. We estimated up to 90% of variation in foliar N concentration using partial least squares (PLS regression of full-spectrum field spectrometer reflectance data. Landsat 7 reflectance data explained up to 70% of % foliar N and 67% of aboveground biomass. Spectrally estimated foliar N or aboveground biomass had negative relationships with belowground biomass and root:shoot ratio in both Schoenoplectus acutus and Typha, consistent with a balanced growth model, which suggests plants only allocate growth belowground when additional nutrients are necessary to support shoot development. Hybrid models explained up to 76% of variation in belowground biomass and 86% of variation in root:shoot ratio. Our modeling approach provides a method for developing maps of spatial variation in wetland belowground biomass.

  17. Modelling tree biomasses in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Repola, J.

    2013-06-01

    Biomass equations for above- and below-ground tree components of Scots pine (Pinus sylvestris L), Norway spruce (Picea abies [L.] Karst) and birch (Betula pendula Roth and Betula pubescens Ehrh.) were compiled using empirical material from a total of 102 stands. These stands (44 Scots pine, 34 Norway spruce and 24 birch stands) were located mainly on mineral soil sites representing a large part of Finland. The biomass models were based on data measured from 1648 sample trees, comprising 908 pine, 613 spruce and 127 birch trees. Biomass equations were derived for the total above-ground biomass and for the individual tree components: stem wood, stem bark, living and dead branches, needles, stump, and roots, as dependent variables. Three multivariate models with different numbers of independent variables for above-ground biomass and one for below-ground biomass were constructed. Variables that are normally measured in forest inventories were used as independent variables. The simplest model formulations, multivariate models (1) were mainly based on tree diameter and height as independent variables. In more elaborated multivariate models, (2) and (3), additional commonly measured tree variables such as age, crown length, bark thickness and radial growth rate were added. Tree biomass modelling includes consecutive phases, which cause unreliability in the prediction of biomass. First, biomasses of sample trees should be determined reliably to decrease the statistical errors caused by sub-sampling. In this study, methods to improve the accuracy of stem biomass estimates of the sample trees were developed. In addition, the reliability of the method applied to estimate sample-tree crown biomass was tested, and no systematic error was detected. Second, the whole information content of data should be utilized in order to achieve reliable parameter estimates and applicable and flexible model structure. In the modelling approach, the basic assumption was that the biomasses of

  18. Communal biomass conversion plants

    International Nuclear Information System (INIS)

    1991-06-01

    The Coordinating Committee set up by the Danish government in 1986 were given the responsibility of investigating the potentials for biomass conversion plants in Denmark, especially in relation to agricultural, environmental and energy aspects. The results of the Committee's plan of management for this project are presented. This main report covers 13 background reports which deal with special aspects in detail. The report describes the overall plan of management, the demonstration and follow-up programme and the individual biogas demonstration plants. Information gained from these investigations is presented. The current general status, (with emphasis on the technical and economical aspects) and the prospects for the future are discussed. The interest other countries have shown in Danish activities within the field of biogas production is described, and the possibilities for Danish export of technology and know-how in this relation are discussed. It is claimed that Denmark is the first country that has instigated a coordinated development programme for biomass conversion plants. (AB) 24 refs

  19. 12 CFR 347.303 - Allocated transfer risk reserve.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Allocated transfer risk reserve. 347.303... GENERAL POLICY INTERNATIONAL BANKING International Lending § 347.303 Allocated transfer risk reserve. (a) Establishment of Allocated Transfer Risk Reserve. A banking institution shall establish an allocated transfer...

  20. 40 CFR 60.4142 - Hg allowance allocations.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Hg allowance allocations. 60.4142... Coal-Fired Electric Steam Generating Units Hg Allowance Allocations § 60.4142 Hg allowance allocations. (a)(1) The baseline heat input (in MMBtu) used with respect to Hg allowance allocations under...

  1. Allocating environmental liabilities within a facilities agreement

    International Nuclear Information System (INIS)

    Harvie, A.

    2000-01-01

    Some environmental issues at jointly owned oil and gas facilities in Alberta are examined, including ways to allocate liability for those issues among the facility's owners, and between the facility's owners and custom users. Causes of environmental contamination, the scope of clean-up costs and some industry initiatives to sort out the question of who pays the environmental costs are also discussed. Some aspects of the legislation in Alberta imposing environmental liabilities on parties to a construction, ownership and operation (CO and O) agreement, and relevant provisions of the Petroleum Joint Venture Association (PJVA)'s Model Operating Procedure are also explained. The author concludes by regretting the industry's failure to develop adequate mechanisms to allocate the costs of environmental damage resulting from operations, and by recommending that agreements pertaining to joint ownership of a facility should address the issues involved in allocating environmental liabilities

  2. Optimal allocation of reviewers for peer feedback

    DEFF Research Database (Denmark)

    Wind, David Kofoed; Jensen, Ulf Aslak; Jørgensen, Rasmus Malthe

    2017-01-01

    Peer feedback is the act of letting students give feedback to each other on submitted work. There are multiple reasons to use peer feedback, including students getting more feedback, time saving for teachers and increased learning by letting students reflect on work by others. In order for peer...... feedback to be effective students should give and receive useful feedback. A key challenge in peer feedback is allocating the feedback givers in a good way. It is important that reviewers are allocated to submissions such that the feedback distribution is fair - meaning that all students receive good...... feedback. In this paper we present a novel way to intelligently allocate reviewers for peer feedback. We train a statistical model to infer the quality of feedback based on a dataset of feedback quality evaluations. This dataset contains more than 20,000 reviews where the receiver of the feedback has...

  3. Robust resource allocation in future wireless networks

    CERN Document Server

    Parsaeefard, Saeedeh; Mokari, Nader

    2017-01-01

    This book presents state-of-the-art research on robust resource allocation in current and future wireless networks. The authors describe the nominal resource allocation problems in wireless networks and explain why introducing robustness in such networks is desirable. Then, depending on the objectives of the problem, namely maximizing the social utility or the per-user utility, cooperative or competitive approaches are explained and their corresponding robust problems are considered in detail. For each approach, the costs and benefits of robust schemes are discussed and the algorithms for reducing their costs and improving their benefits are presented. Considering the fact that such problems are inherently non-convex and intractable, a taxonomy of different relaxation techniques is presented, and applications of such techniques are shown via several examples throughout the book. Finally, the authors argue that resource allocation continues to be an important issue in future wireless networks, and propose spec...

  4. Characterization of the loss allocation techniques for radial systems with distributed generation

    International Nuclear Information System (INIS)

    Carpaneto, Enrico; Chicco, Gianfranco; Sumaili Akilimali, Jean

    2008-01-01

    In the restructured electricity industry, meaningful loss allocation methods are required in order to send correct signals to the market taking into account the location and characteristics of loads and generations, including the local sources forming the distributed generation (DG). This paper addresses the issues related to loss allocation in radial distribution systems with DG, with a three-fold focus. First, the key differences in the formulation of the loss allocation problem for radial distribution systems with respect to transmission systems are discussed, specifying the modeling and computational issues concerning the treatment of the slack node in radial distribution systems. Then, the characteristics of derivative-based and circuit-based loss allocation techniques are presented and compared, illustrating the arrangements used for adapting the various techniques to be applied to radial distribution systems with DG. Finally, the effects of introducing voltage-controllable local generation on the calculation of the loss allocation coefficients are discussed, proposing the adoption of a ''reduced'' representation of the system capable of taking into proper account the characteristics of the nodes containing voltage-controllable DG units. Numerical results are provided to show the time evolution of the loss allocation coefficients for distribution systems with variable load and local generation patterns. (author)

  5. Estimation of carbon allocation of Macauba palm (Acrocomia aculeata) - A new Brazilian biofuel alternative

    Science.gov (United States)

    Imbuzeiro, H. A.

    2016-12-01

    The Macauba palm (Acrocomia aculeata (Jacq.) Lood. ex Mart) is a native oil palm of the tropical America growing in anthropic areas, especially in grazing lands of Brazilian Cerrado. Macauba palm displays intense fruiting which results in high fruit and oil yield (3.0 - 6.0 ton/ha/year). The main Macauba palm differentials are: it is adapted to the environment with marked water restriction (1000 mm annual precipitation) which makes it resistant to drought and it does not compete with areas of rainforest; the oil is similar in composition to the African palm oil (Elaeis guineensis Jacq.) and can be used in several industrial applications such as biofuels, food, cosmetics, pharmaceutics and oil chemistry. Additionally, Macauba fruit processing generates several by-products like edible pulp bran, high-protein edible kernel bran, dense endocarp biomass, and husk biomass, all valuable products. Today, 172 million hectares of Brazilian land are used for grazing, of which 30 million hectares of these lands are degraded due to poor land use, 6 million in the state of Minas Gerais, in Brazil. Macauba could be cultivated in these degraded lands and is a candidate to become the main raw material for production of biokerosene. A new productive chain is forming in Brazil, the first commercial plantation of Macauba was implemented last year in Minas Gerais state and it is important to estimate the environmental impacts of this plantation, in terms of carbon (C) allocation. There is a lack of experimental data on Macauba carbon allocation and this study aimed to estimate the carbon allocation (leaves, stems and roots) of Macauba palm. The results suggest that Macauba palm is important in contributing to the carbon allocation and nutrient cycling.

  6. Estimation of carbon allocation of Macauba palm (Acrocomia aculeata) - A new Brazilian biofuel alternative

    Science.gov (United States)

    Imbuzeiro, H. A.; Moreira, S. L. S.; Motoike, S. Y.; Fernandes, R. B. A.

    2017-12-01

    The Macauba palm (Acrocomia aculeata (Jacq.) Lood. ex Mart) is a native oil palm of the tropical America growing in anthropic areas, especially in grazing lands of Brazilian Cerrado. Macauba palm displays intense fruiting which results in high fruit and oil yield (3.0 - 6.0 ton/ha/year). The main Macauba palm differentials are: it is adapted to the environment with marked water restriction (1000 mm annual precipitation) which makes it resistant to drought and it does not compete with areas of rainforest; the oil is similar in composition to the African palm oil (Elaeis guineensis Jacq.) and can be used in several industrial applications such as biofuels, food, cosmetics, pharmaceutics and oil chemistry. Additionally, Macauba fruit processing generates several by-products like edible pulp bran, high-protein edible kernel bran, dense endocarp biomass, and husk biomass, all valuable products. Today, 172 million hectares of Brazilian land are used for grazing, of which 30 million hectares of these lands are degraded due to poor land use, 6 million in the state of Minas Gerais, in Brazil. Macauba could be cultivated in these degraded lands and is a candidate to become the main raw material for production of biokerosene. A new productive chain is forming in Brazil, the first commercial plantation of Macauba was implemented last year in Minas Gerais state and it is important to estimate the environmental impacts of this plantation, in terms of carbon (C) allocation. There is a lack of experimental data on Macauba carbon allocation and this study aimed to estimate the carbon allocation (leaves, stems and roots) of Macauba palm. The results suggest that Macauba palm is important in contributing to the carbon allocation.

  7. How to Optimize the Commission Allocation

    Directory of Open Access Journals (Sweden)

    Yi Lan

    2017-01-01

    Full Text Available in this paper, the commission allocation mechanism between the mobile application store and the mobile application developer is studied under the game theory. Firstly, based on the non-cooperative game theory, the paper researches the equilibrium solution of the inter-firm game under the conditions of different sales scale, and then extend the study to the circumstance of infinite game. In addition, the paper analyzes the Pareto improvement achieved by choosing cooperative strategy of strategic alliance from different parts. Finally, problem of the commission allocation problem is resolved.

  8. Allocation of Decommissioning and Waste Liabilities

    International Nuclear Information System (INIS)

    Varley, Geoff

    2011-11-01

    The work demonstrates that there are a number of methods available for cost allocation, the pros and cons of which are examined. The study investigates potential proportional and incremental methods in some depth. A recommendation in principle to use the latter methodology is given. It is concluded that a 'fair assumption' is that the potential allocation of costs for 'the RMA Leaching Hall' probably is small, in relation to the total costs, and estimated to be not more than about 175 kSEK, plus any costs associated with decommissioning/ disposal of a number of small pieces of equipment added by the current operator

  9. Vegetal and animal biomass; Les biomasses vegetales et animales

    Energy Technology Data Exchange (ETDEWEB)

    Combarnous, M. [Bordeaux-1 Univ., Lab. Energetique et Phenomenes de Transfert, UMR CNRS ENSAM, 33 - Talence (France)

    2005-07-01

    This presentation concerns all types of biomass of the earth and the seas and the relative implicit consumptions. After an evaluation of the food needs of the human being, the author discusses the solar energy conversion, the energetic flux devoted to the agriculture production, the food chain and the biomass. (A.L.B.)

  10. Biomass and biomass change in lodgepole pine stands in Alberta

    Science.gov (United States)

    Robert A. Monserud; Shongming Huang; Yuqing Yang

    2006-01-01

    We describe methods and results for broad-scale estimation and mapping of forest biomass for the Canadian province of Alberta. Differences over successive decades provided an estimate of biomass change. Over 1500 permanent sample plots (PSP) were analyzed from across the range of lodgepole pine (Pinus contorta var. latifolia Engelm...

  11. Energy production from biomass (Part 1): Overview of biomass.

    Science.gov (United States)

    McKendry, Peter

    2002-05-01

    The use of renewable energy sources is becoming increasingly necessary, if we are to achieve the changes required to address the impacts of global warming. Biomass is the most common form of renewable energy, widely used in the third world but until recently, less so in the Western world. Latterly much attention has been focused on identifying suitable biomass species, which can provide high-energy outputs, to replace conventional fossil fuel energy sources. The type of biomass required is largely determined by the energy conversion process and the form in which the energy is required. In the first of three papers, the background to biomass production (in a European climate) and plant properties is examined. In the second paper, energy conversion technologies are reviewed, with emphasis on the production of a gaseous fuel to supplement the gas derived from the landfilling of organic wastes (landfill gas) and used in gas engines to generate electricity. The potential of a restored landfill site to act as a biomass source, providing fuel to supplement landfill gas-fuelled power stations, is examined, together with a comparison of the economics of power production from purpose-grown biomass versus waste-biomass. The third paper considers particular gasification technologies and their potential for biomass gasification.

  12. Detailed modelling of biomass pyrolysis: biomass structure and composition

    International Nuclear Information System (INIS)

    Hugony, F.; Migliavacca, G.; Faravelli, T.; Ranzi, E.

    2007-01-01

    The research routes followed in the field of numerical modelling development for biomass devolatilization are here summarised. In this first paper a wide introduction concerning the description of the chemical nature of the main classes of compounds which constitute biomasses is reported, it is the starting point for the subsequent description of the developed models, described in the companion paper [it

  13. System and process for biomass treatment

    Science.gov (United States)

    Dunson, Jr., James B; Tucker, III, Melvin P; Elander, Richard T; Lyons, Robert C

    2013-08-20

    A system including an apparatus is presented for treatment of biomass that allows successful biomass treatment at a high solids dry weight of biomass in the biomass mixture. The design of the system provides extensive distribution of a reactant by spreading the reactant over the biomass as the reactant is introduced through an injection lance, while the biomass is rotated using baffles. The apparatus system to provide extensive assimilation of the reactant into biomass using baffles to lift and drop the biomass, as well as attrition media which fall onto the biomass, to enhance the treatment process.

  14. Growing larger with domestication: a matter of physiology, morphology or allocation?

    Science.gov (United States)

    Milla, R; Matesanz, S

    2017-05-01

    Domestication might affect plant size. We investigated whether herbaceous crops are larger than their wild progenitors, and the traits that influence size variation. We grew six crop plants and their wild progenitors under common garden conditions. We measured the aboveground biomass gain by individual plants during the vegetative stage. We then tested whether photosynthesis rate, biomass allocation to leaves, leaf size and specific leaf area (SLA) accounted for variations in whole-plant photosynthesis, and ultimately in aboveground biomass. Despite variations among crops, domestication generally increased the aboveground biomass (average effect +1.38, Cohen's d effect size). Domesticated plants invested less in leaves and more in stems than their wild progenitors. Photosynthesis rates remained similar after domestication. Variations in whole-plant C gains could not be explained by changes in leaf photosynthesis. Leaves were larger after domestication, which provided the main contribution to increases in leaf area per plant and plant-level C gain, and ultimately to larger aboveground biomass. In general, cultivated plants have become larger since domestication. In our six crops, this occurred despite lower investment in leaves, comparable leaf-level photosynthesis and similar biomass costs of leaf area (i.e. SLA) than their wild progenitors. Increased leaf size was the main driver of increases in aboveground size. Thus, we suggest that large seeds, which are also typical of crops, might produce individuals with larger organs (i.e. leaves) via cascading effects throughout ontogeny. Larger leaves would then scale into larger whole plants, which might partly explain the increases in size that accompanied domestication. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.

  15. ALTENER - Biomass event in Finland

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    The publication contains the lectures held in the Biomass event in Finland. The event was divided into two sessions: Fuel production and handling, and Co-combustion and gasification sessions. Both sessions consisted of lectures and the business forum during which the companies involved in the research presented themselves and their research and their equipment. The fuel production and handling session consisted of following lectures and business presentations: AFB-NETT - business opportunities for European biomass industry; Wood waste in Europe; Wood fuel production technologies in EU- countries; new drying method for wood waste; Pellet - the best package for biofuel - a view from the Swedish pelletmarket; First biomass plant in Portugal with forest residue fuel; and the business forum of presentations: Swedish experiences of willow growing; Biomass handling technology; Chipset 536 C Harvester; KIC International. The Co-combustion and gasification session consisted of following lectures and presentations: Gasification technology - overview; Overview of co-combustion technology in Europe; Modern biomass combustion technology; Wood waste, peat and sludge combustion in Enso Kemi mills and UPM-Kymmene Rauma paper mill; Enhanced CFB combustion of wood chips, wood waste and straw in Vaexjoe in Sweden and Grenaa CHP plant in Denmark; Co-combustion of wood waste; Biomass gasification projects in India and Finland; Biomass CFB gasifier connected to a 350 MW{sub t}h steam boiler fired with coal and natural gas - THERMIE demonstration project in Lahti (FI); Biomass gasification for energy production, Noord Holland plant in Netherlands and Arbre Energy (UK); Gasification of biomass in fixed bed gasifiers, Wet cleaning and condensing heat recovery of flue gases; Combustion of wet biomass by underfeed grate boiler; Research on biomass and waste for energy; Engineering and consulting on energy (saving) projects; and Research and development on combustion of solid fuels

  16. Type monotonic allocation schemes for multi-glove games

    OpenAIRE

    Brânzei, R.; Solymosi, T.; Tijs, S.H.

    2007-01-01

    Multiglove markets and corresponding games are considered.For this class of games we introduce the notion of type monotonic allocation scheme.Allocation rules for multiglove markets based on weight systems are introduced and characterized.These allocation rules generate type monotonic allocation schemes for multiglove games and are also helpful in proving that each core element of the corresponding game is extendable to a type monotonic allocation scheme.The T-value turns out to generate a ty...

  17. Putting urban biomass on the map: contrasting case studies from three climactic zones

    Science.gov (United States)

    Raciti, S. M.; Hutyra, L.; Rao, P.; McHale, M. R.

    2012-12-01

    There is evidence that urban vegetation can provide important ecosystem services, however, existing maps of vegetation biomass tend to exclude developed land uses or report them as having little or no biomass. We used field and remote sensing data from the Boston, MA, Seattle, WA, and Phoenix Arizona metropolitan areas to 1) assess the potential for predicting urban biomass from remote sensing data, 2) explore the influence of land use and climate on urban biomass, 3) generate new biomass maps that explicitly include urban land uses, and 4) compare these biomass maps to existing products. For each metropolitan area, vegetation biomass was estimated for field plots using tree/shrub species, diameter at breast height (DBH) or ground level (DGL), and allometric equations. These field data were paired with geospatial data to assess the potential for creating vegetation biomass maps for each metropolitan area. The geospatial data included land use, land cover, impervious surface fraction, population density, and two remotely-sensed vegetation indices (Normalized Difference Vegetation Index [NDVI] and Enhanced Vegetation Index [EVI]). Preliminary findings suggest that the ability to predict biomass from remote sensing data varies with land use, climate, and dominant vegetation type. Existing vegetation biomass maps may considerably underestimate biomass, particularly in regions with extensive urban land cover. Urban areas are rapidly expanding and future development patterns will have significant impacts on terrestrial carbon stocks, anthropogenic emissions, and the ecosystem services provided by remnant and regrowing vegetation.

  18. Allometric Equations for Estimating Compartment Biomass and Stem Volume in Mature Hybrid Poplars: General or Site-Specific?

    Directory of Open Access Journals (Sweden)

    Julien Fortier

    2017-08-01

    Full Text Available We evaluated the extent to which general or site-specific allometric equations, using diameter at breast height (DBH as a predictor, are more accurate for estimating stem volume, stem biomass, branch biomass, aboveground woody biomass, and coarse root biomass in 14 year-old plantations of Populus canadensis × Populus maximowiczii (clone DN × M-915508 located along an environmental gradient in southern Québec (eastern Canada. The effect of tree size and site on stem wood basic density, moisture content, and proportion of branch biomass was also evaluated. For stem volume, stem biomass, and aboveground biomass, site-specific and general models had comparable fit and accuracy, but lower Akaike’s Information Criterion (AICc values were observed for the general models. For the branch and coarse root biomass, higher fit and accuracy and lower AICc values were observed for the site-specific models. Allometric trajectory changes (plastic allometry across sites were mainly observed for coarse root biomass, branch biomass, and stem volume. On the low fertility site, allocation was increased to coarse roots and decreased to stem volume. Site-specific tradeoffs between tree architecture and stem wood density explained the relatively invariant allometry for the whole aboveground woody biomass across the plantation sites. On the high fertility sites, basic wood density was the lowest and declined as tree DBH increased. At all sites, stem wood moisture content and the proportion of branch biomass increased with DBH. Overall, this study showed that biomass allometry, tree architecture, and biomass quality are a function of both tree size and plantation environment in hybrid poplar. Allometric model selection (site-specific or general should depend on the objective pursued (evaluation of yield, nutrient budget, carbon stocks.

  19. Biomass plantations - energy farming

    Energy Technology Data Exchange (ETDEWEB)

    Paul, S.

    1981-02-01

    Mounting oil import bills in India are restricting her development programmes by forcing the cutting down of the import of other essential items. But the countries of the tropics have abundant sunlight and vast tracts of arable wastelands. Energy farming is proposed in the shape of energy plantations through forestry or energy cropping through agricultural media, to provide power fuels for transport and the industries and also to provide fuelwoods for the domestic sector. Short rotation cultivation is discussed and results are given of two main species that are being tried, ipil-ipil and Casuarina. Evaluations are made on the use of various crops such as sugar cane, cassava and kenaf as fuel crops together with hydrocarbon plants and aquatic biomass. (Refs. 20)

  20. Biomass Deconstruction and Recalcitrance

    DEFF Research Database (Denmark)

    Zhang, Heng

    reflections of plant species, tissue or organ types, genetic traits and environment. Effects of cultivar type, anatomical distribution, chemical composition, fertilizer level and growth year have been observed during in vitro and in vivo trials. A similar approach is here taken to further investigate: 1). How......This thesis is about the use of an agricultural residue as a feedstock for fermentable sugars to be used for second generation (2G) bioethanol. The main focus of this thesis work is upon the recalcitrance of different anatomical fractions of wheat straw. Biomass recalcitrance is a collective...... recalcitrance or degradability varies between leaf and stem as found in different wheat cultivars. 2). Chemical, physical and structural differences between wheat straw leaf and stem which may be responsible for observed differences in their bio-degradability. As a tool to assess the variation...

  1. Mobile Biomass Pelletizing System

    Energy Technology Data Exchange (ETDEWEB)

    Thomas Mason

    2009-04-16

    This grant project examines multiple aspects of the pelletizing process to determine the feasibility of pelletizing biomass using a mobile form factor system. These aspects are: the automatic adjustment of the die height in a rotary-style pellet mill, the construction of the die head to allow the use of ceramic materials for extreme wear, integrating a heat exchanger network into the entire process from drying to cooling, the use of superheated steam for adjusting the moisture content to optimum, the economics of using diesel power to operate the system; a break-even analysis of estimated fixed operating costs vs. tons per hour capacity. Initial development work has created a viable mechanical model. The overall analysis of this model suggests that pelletizing can be economically done using a mobile platform.

  2. Biomass resource assessment for China

    Energy Technology Data Exchange (ETDEWEB)

    Li Jingjing; Zhou Aiming [Energy Research Institute of State Planning and Development Commission (China)

    1999-07-01

    This paper calculated and assessed the biomass resource availability in China, especially straw and stalk, domestic animal excreta and municipal solid waste. The assessment showed that biomass energy will be a rich and sustainable resource in China, important for developing the social economy and improving the environment in the future. (author)

  3. Woody biomass logistics [Chapter 14

    Science.gov (United States)

    Robert Keefe; Nathaniel Anderson; John Hogland; Ken Muhlenfeld

    2014-01-01

    The economics of using woody biomass as a fuel or feedstock for bioenergy applications is often driven by logistical considerations. Depending on the source of the woody biomass, the acquisition cost of the material is often quite low, sometimes near zero. However, the cost of harvesting, collection, processing, storage, and transportation from the harvest site to end...

  4. Forest biomass-based energy

    Science.gov (United States)

    Janaki R. R. Alavalapati; Pankaj Lal; Andres Susaeta; Robert C. Abt; David N. Wear

    2013-01-01

    Key FindingsHarvesting woody biomass for use as bioenergy is projected to range from 170 million to 336 million green tons by 2050, an increase of 54 to 113 percent over current levels.Consumption projections for forest biomass-based energy, which are based on Energy Information Administration projections, have a high level of...

  5. Forest biomass sustainability and availability

    Science.gov (United States)

    K.E. Skog; John Stanturf

    2011-01-01

    This chapter provides a synthesis of information on potential supply of forest biomass given needs for sustainable development of forestry. Sustainability includes maintenance of water supply, biodiversity, and carbon storage as well as timber products, community development, and recreation. Biomass removals can reduce fire hazard and insect and disease attack, restore...

  6. Refining fast pyrolysis of biomass

    NARCIS (Netherlands)

    Westerhof, Roel Johannes Maria

    2011-01-01

    Pyrolysis oil produced from biomass is a promising renewable alternative to crude oil. Such pyrolysis oil has transportation, storage, and processing benefits, none of which are offered by the bulky, inhomogeneous solid biomass from which it originates. However, pyrolysis oil has both a different

  7. Aboveground Biomass and Litterfall Dynamics in Secondary Forest ...

    African Journals Online (AJOL)

    The differences in aboveground biomass, litterfall patterns and the seasonality of litterfall in three secondary forest fields aged 1, 5 and 10 years of age regenerating from degraded abandoned rubber plantation and a mature forest were studied in southern Nigeria. This is with a view to understanding the possibility of ...

  8. Adaptive resource allocation for efficient patient scheduling

    NARCIS (Netherlands)

    Vermeulen, Ivan B.; Bohte, Sander M.; Elkhuizen, Sylvia G.; Lameris, Han; Bakker, Piet J. M.; La Poutré, Han

    2009-01-01

    Efficient scheduling of patient appointments on expensive resources is a complex and dynamic task. A resource is typically used by several patient groups. To service these groups, resource capacity is often allocated per group, explicitly or implicitly. Importantly, due to fluctuations in demand,

  9. Allocation of Cognitive Resources in Translation

    DEFF Research Database (Denmark)

    Hvelplund, Kristian Tangsgaard

    The present study is an empirical investigation of translators' allocation of cognitive resources during the translation process, and it aims at investigating how translators' mental processing resources are put to use during translation. The study bases ts analyses on quantitative eye...

  10. Approximate Dynamic Programming for Military Resource Allocation

    Science.gov (United States)

    2014-12-26

    18] Gerald Brown, Matthew Carlyle, Douglas Diehl, Jeffrey Kline, and Kevin Wood. A two-sided optimization for theater ballistic missile defense. Oper...Conference Proceedings. 1999 IEEE International Conference on, volume 1, pages 1061–1066. IEEE, 1999. [78] TE Phipps and AL Karp . Optimum allocation of

  11. Biased Allocation of Faces to Social Categories

    NARCIS (Netherlands)

    Dotsch, R.; Wigboldus, D.H.J.; Knippenberg, A.F.M. van

    2011-01-01

    Three studies show that social categorization is biased at the level of category allocation. In all studies, participants categorized faces. In Studies 1 and 2, participants overallocated faces with criminal features-a stereotypical negative trait-to the stigmatized Moroccan category, especially if

  12. Patient flow based allocation of hospital resources.

    Science.gov (United States)

    Vissers, J M

    1995-01-01

    The current practice of allocating resources within a hospital introduces peaks and troughs in the workloads of departments and leads therefore to loss of capacity. This happens when requirements for capacity coordination are not adequately taken into account in the decision making process of allocating resources to specialties. The first part of this research involved an analysis of the hospital's production system on dependencies between resources, resulting in a number of capacity coordination requirements that need to be fulfilled for optimized resource utilization. The second, modelling, part of the study involved the development of a framework for resource management decision making, of a set of computer models to support hospital managerial decision making on resource allocation issues in various parts of the hospital, and of an implementation strategy for the application of the models to concrete hospital settings. The third part of the study was devoted to a number of case-studies, illustrating the use of the models when applied in various resource management projects, such as a reorganization of an operating theatre timetable, or the development of a master plan for activities of a group of general surgeons serving two locations of a merged hospital system. The paper summarizes the main findings of the study and concludes with a discussion of results obtained with the new allocation procedure and with recommendations for future research.

  13. FARM RESOURCE ALLOCATION AND PROFITABILITY OF ...

    African Journals Online (AJOL)

    Unique cropping systems have emerged in Nigeria to suit limited farmer resources and production objectives in humid forest inland valley ecosystems. But the basis for farm resource allocation and profitability of different crop enterprises are not properly understood. This study is based on a survey of 48 randomly selected ...

  14. Human Resource Subjects Allocation and Students' Academic ...

    African Journals Online (AJOL)

    This study investigated human resource subjects' allocation and students' academic performance in Secondary Schools in Obudu, Nigeria. The relevant variables of teachers subject was used as independent variable while the dependent variables were students' academic performance. Six hundred teachers from 20 ...

  15. Analysts' earnings forecasts and international asset allocation

    NARCIS (Netherlands)

    Huijgen, Carel; Plantinga, Auke

    1999-01-01

    The aim of this paper is to investigate whether financial analysts’ earnings forecasts are informative from the viewpoint of allocating investments across different stock markets. Therefore we develop a country forecast indicator reflecting the analysts’ prospects for specific stock markets. The

  16. Do capital flows change domestic credit allocation?

    NARCIS (Netherlands)

    Samarina, Anna; Bezemer, Dirk

    Since the 1990s, domestic bank credit has been reallocated away from lending to non-financial business and toward households. An expanding literature discusses negative effects on growth and stability of this change in credit allocation. We research its drivers. We hypothesize that if foreign

  17. Cooperation and profit allocation in distribution chains

    NARCIS (Netherlands)

    Guardiola, L.A.; Meca, A.; Timmer, Judith B.

    2005-01-01

    We study the coordination of actions and the allocation of profit in distribution chains under decentralized control. We consider distribution chains in which a single supplier supplies goods for replenishment of stocks of several retailers who, in turn, sell these goods to their own separate

  18. Cooperation and profit allocation in distribution chains

    NARCIS (Netherlands)

    Guardiola, Luis A.; Meca, Ana; Timmer, Judith B.

    2007-01-01

    We study the coordination of actions and the allocation of profit in supply chains under decentralized control in which a single supplier supplies several retailers with goods for replenishment of stocks. The goal of the supplier and the retailers is to maximize their individual profits. Since the

  19. Issues in organ procurement, allocation, and transplantation.

    Science.gov (United States)

    Nierste, Deborah

    2013-01-01

    Organ transplantation extends lives and improves health but presents complex ethical dilemmas for nurses caring for donors, recipients, and their families. This article overviews organ procurement and allocation, discusses ethical dilemmas in transplantation, and offers strategies from professional and biblical perspectives for coping with moral distress and maintaining compassionate care.

  20. 50 CFR 648.87 - Sector allocation.

    Science.gov (United States)

    2010-10-01

    ... and restrictions of this section. The sector allocation proposal must contain an appropriate analysis... partners in a corporation owning a permit; who are partners (general or limited) to a permit owner; who, in... biological, economic, and social impacts of sectors and their fishing operations consistent with...

  1. Multiobjective optimal allocation problem with probabilistic non ...

    African Journals Online (AJOL)

    This paper considers the optimum compromise allocation in multivariate stratified sampling with non-linear objective function and probabilistic non-linear cost constraint. The probabilistic non-linear cost constraint is converted into equivalent deterministic one by using Chance Constrained programming. A numerical ...

  2. RAOPS: Resource Allocation Optimization Program for Safegurards

    Energy Technology Data Exchange (ETDEWEB)

    Zardecki, A.; Markin, J.T.

    1994-03-01

    RAOPS--Resource Allocation Optimization Program for Safeguards is extended to a multiobjective return function having the detection probability and expected detection time as criteria. The expected detection time is included as a constraint, based on the well-known Avenhaus model of the optimum number of inventory periods. Examples of computation are provided.

  3. 45 CFR 1355.57 - Cost allocation.

    Science.gov (United States)

    2010-10-01

    ... information retrieval system described in § 1355.53 of this part shall be treated as necessary for the proper and efficient administration of the State plan under title IV-E, without regard to whether the system... 45 Public Welfare 4 2010-10-01 2010-10-01 false Cost allocation. 1355.57 Section 1355.57 Public...

  4. 42 CFR 24.2 - Allocation.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Allocation. 24.2 Section 24.2 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES PERSONNEL SENIOR BIOMEDICAL RESEARCH SERVICE § 24... talent. (e) The Secretary will ensure that SBRS slots are used in support of high priority programs...

  5. Cost Allocation in a Bank ATM Network

    NARCIS (Netherlands)

    Bjorndal, E.; Hamers, H.; Koster, M.A.L.

    2004-01-01

    We consider a situation in which a group of banks consider connecting their Automated Teller Machines (ATMs) in a network, so that the banks customers may use ATMs of any bank in the network. The problem studied is that of allocating the total transaction costs arising in the network, among the

  6. Cost Allocation in a Bank ATM Network

    NARCIS (Netherlands)

    Bjorndal, E.; Hamers, H.J.M.; Koster, M.A.L.

    2003-01-01

    We consider a situation in which a group of banks consider connecting their Automated TellerMachines (ATMs) in a network, so that the banks customers may use ATMs of any bank in the network.The problem studied is that of allocating the total transaction costs arising in the network, among the

  7. Capital Allocation Effects of Financial Reporting Regulation

    NARCIS (Netherlands)

    Koenigsgruber, R.

    2012-01-01

    This paper analyses the effects of stricter financial reporting enforcement on capital allocation and reporting quality in a game-theoretic model and derives conclusions about optimal enforcement strictness. Analysis of the model shows that reporting quality strictly increases with tighter

  8. Sequential auctions for full truckload allocation

    NARCIS (Netherlands)

    Mes, Martijn R.K.

    2008-01-01

    In this thesis we examine the use of sequential auctions for the dynamic allocation of transportation jobs. For all players, buyers and sellers, we develop strategies and examine their performance both in terms of individual benefits and with respect to the global logistical performance (resource

  9. Spatial allocation of forest recreation value

    Science.gov (United States)

    Kenneth A. Baerenklau; Armando Gonzalez-Caban; Catrina Paez; Edgard Chavez

    2009-01-01

    Non-market valuation methods and geographic information systems are useful planning and management tools for public land managers. Recent attention has been given to investigation and demonstration of methods for combining these tools to provide spatially-explicit representations of non-market value. Most of these efforts have focused on spatial allocation of...

  10. Financial Resource Allocation in Higher Education

    Science.gov (United States)

    Ušpuriene, Ana; Sakalauskas, Leonidas; Dumskis, Valerijonas

    2017-01-01

    The paper considers a problem of financial resource allocation in a higher education institution. The basic financial management instruments and the multi-stage cost minimization model created are described involving financial instruments to constraints. Both societal and institutional factors that determine the costs of educating students are…

  11. Modelling of biomass utilization for energy purpose

    Energy Technology Data Exchange (ETDEWEB)

    Grzybek, Anna (ed.)

    2010-07-01

    the overall farms structure, farms land distribution on several separate subfields for one farm, villages' overpopulation and very high employment in agriculture (about 27% of all employees in national economy works in agriculture). Farmers have low education level. In towns 34% of population has secondary education and in rural areas - only 15-16%. Less than 2% inhabitants of rural areas have higher education. The structure of land use is as follows: arable land 11.5%, meadows and pastures 25.4%, forests 30.1%. Poland requires implementation of technical and technological progress for intensification of agricultural production. The reason of competition for agricultural land is maintenance of the current consumption level and allocation of part of agricultural production for energy purposes. Agricultural land is going to be key factor for biofuels production. In this publication research results for the Project PL0073 'Modelling of energetical biomass utilization for energy purposes' have been presented. The Project was financed from the Norwegian Financial Mechanism and European Economic Area Financial Mechanism. The publication is aimed at moving closer and explaining to the reader problems connected with cultivations of energy plants and dispelling myths concerning these problems. Exchange of fossil fuels by biomass for heat and electric energy production could be significant input in carbon dioxide emission reduction. Moreover, biomass crop and biomass utilization for energetical purposes play important role in agricultural production diversification in rural areas transformation. Agricultural production widening enables new jobs creation. Sustainable development is going to be fundamental rule for Polish agriculture evolution in long term perspective. Energetical biomass utilization perfectly integrates in the evolution frameworks, especially on local level. There are two facts. The fist one is that increase of interest in energy crops in Poland

  12. Fusion characterization of biomass ash

    DEFF Research Database (Denmark)

    Ma, Teng; Fan, Chuigang; Hao, Lifang

    2016-01-01

    The ash fusion characteristics are important parameters for thermochemical utilization of biomass. In this research, a method for measuring the fusion characteristics of biomass ash by Thermo-mechanical Analyzer, TMA, is described. The typical TMA shrinking ratio curve can be divided into two...... stages, which are closely related to ash melting behaviors. Several characteristics temperatures based on the TMA curves are used to assess the ash fusion characteristics. A new characteristics temperature, Tm, is proposed to represent the severe melting temperature of biomass ash. The fusion...... characteristics of six types of biomass ash have been measured by TMA. Compared with standard ash fusibility temperatures (AFT) test, TMA is more suitable for measuring the fusion characteristics of biomass ash. The glassy molten areas of the ash samples are sticky and mainly consist of K-Ca-silicates....

  13. Conditioning biomass for microbial growth

    Science.gov (United States)

    Bodie, Elizabeth A; England, George

    2015-03-31

    The present invention relates to methods for improving the yield of microbial processes that use lignocellulose biomass as a nutrient source. The methods comprise conditioning a composition comprising lignocellulose biomass with an enzyme composition that comprises a phenol oxidizing enzyme. The conditioned composition can support a higher rate of growth of microorganisms in a process. In one embodiment, a laccase composition is used to condition lignocellulose biomass derived from non-woody plants, such as corn and sugar cane. The invention also encompasses methods for culturing microorganisms that are sensitive to inhibitory compounds in lignocellulose biomass. The invention further provides methods of making a product by culturing the production microorganisms in conditioned lignocellulose biomass.

  14. Biomass in Switzerland. Energy production

    International Nuclear Information System (INIS)

    Guggisberg, B.

    2006-01-01

    In the long term, biomass could be used for energy production in a three times more intensive way, compared to current figures. A major contribution would be delivered to Switzerland's energy supply. Numerous biomass conversion technologies do exist, for the production of heat, power or vehicle fuel. However, the implementation of such a large-scale utilisation of biomass requires a couple of strategic decisions in order to improve the framework conditions for biomass development and precisely target the supporting measures applicable to both research and pilot plants. In short, a clear and efficient strategy is necessary in what regards biomass, that will be used for the definition of a future catalogue of measures. (author)

  15. Biomass as a modern fuel

    International Nuclear Information System (INIS)

    Hall, D.O.; House, J.

    1994-01-01

    Case studies are presented for several developed and developing countries. Constraints involved in modernising biomass energy and the potential for turning them into entrepreneurial opportunities are discussed. It is concluded that the long term impacts of biomass programmes and projects depend mainly on ensuring sustainability, flexibility and replicability while taking account of local conditions and providing multiple benefits. Implementation of biomass projects requires governmental policy initiatives that will internalise the external economic, social and environmental costs of conventional fuel sources so that biomass fuels can become competitive on a ''level playing field''. Policies are also required to encourage R and D and commercialisation of biomass energy programs in close co-ordination with the private sector. (author)

  16. Energy from biomass. Teaching material; Energie aus Biomasse. Ein Lehrmaterial

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-04-01

    The textbook discusses the available options for power and heat generation from biomass as well as the limits of biomass-based power supply. The main obstacle apart from the high cost is a lack of knowledge, which the book intends to remedy. It addresses students of agriculture, forestry, environmental engineering, heating systems engineering and apprentice chimney sweepers, but it will also be useful to all other interested readers. [German] Biomasse kann aufgrund seiner vielfaeltigen Erscheinungs- und Umwandlungsformen sowohl als Brennstoff zur Waerme- und Stromgewinnung oder als Treibstoff eingesetzt werden. Die energetische Nutzung von Biomasse birgt zudem nicht zu verachtende Vorteile. Zum einen wegen des Beitrags zum Klimaschutz aufgrund der CO{sub 2}-Neutralitaet oder einfach, weil Biomasse immer wieder nachwaechst und von fossilen Ressourcen unabhaengig macht. All den bisher erschlossenen Moeglichkeiten der energetischen Nutzung von Biomasse moechte dieses Lehrbuch Rechnung tragen. Es zeigt aber auch die Grenzen auf, die mit der Energieversorgung durch Bioenergie einhergehen. Hohe Kosten und ein erhebliches Informationsdefizit behinderten bisher eine verstaerkte Nutzung dieses Energietraeges. Letzterem soll dieses Lehrbuch entgegenwirken. Das vorliegende Lehrbuch wurde fuer die Aus- und Weiterbildung erstellt. Es richtet sich vor allem an angehende Land- und Forstwirte, Umwelttechniker, Heizungsbauer und Schornsteinfeger, ist aber auch fuer all diejenigen interessant, die das Thema ''Energie aus Biomasse'' verstehen und ueberblicken moechten. (orig.)

  17. Treatment of biomass to obtain fermentable sugars

    Science.gov (United States)

    Dunson, Jr., James B.; Tucker, Melvin [Lakewood, CO; Elander, Richard [Evergreen, CO; Hennessey, Susan M [Avondale, PA

    2011-04-26

    Biomass is pretreated using a low concentration of aqueous ammonia at high biomass concentration. Pretreated biomass is further hydrolyzed with a saccharification enzyme consortium. Fermentable sugars released by saccharification may be utilized for the production of target chemicals by fermentation.

  18. Genotypic Diversity for Biomass Accumulation and Shoot-Root Allometry in the Grass Brachypodium distachyon

    Science.gov (United States)

    Jansson, C.; Handakumbura, P. P.; Fortin, D.; Stanfill, B.; Rivas-Ubach, A.

    2017-12-01

    Predicting carbon uptake, assimilation and allocation for current and future biogeographical environments, including climate, is critical for our ability to select and/or design plant genotypes to meet increasing demand for plant biomass going into food, feed and energy production, while at the same time maintain or increase soil organic matter (SOM for soil fertility and carbon storage, and reduce emission of greenhouse gasses. As has been demonstrated for several plant species allometric relationships may differ between plant genotypes. Exploring plant genotypic diversity for biomass accumulation and allometry will potentially enable selection of genotypes with high CO2 assimilation and favorable allocation of recent photosynthate into above-ground and below-ground biomass. We are investigating genotypic diversity for PFTs in natural accessions of the annual C3 grass Brachypodium distachyon under current and future climate scenarios and how genotypic diversity correlates with metabolite profiles in aboveground and below-ground biomass. In the current study, we compare effects from non-stressed and drought conditions on biomass accumulation and shoot-root allometry.

  19. Introduction to biomass energy project financing, funding sources and government strategies

    International Nuclear Information System (INIS)

    Nordlinger, D.E.; Shaw, F.C.

    1995-01-01

    Biomass projects can help developing countries to protect their environment as well as to build a modem infrastructure. However, such projects present, in addition to the more typical risks associated with fossil-fuel projects, certain risks relating to the unique technologies and fuels used in such projects. Further, their location in developing countries regularly creates enhanced political and credit risk as well. Biomass power projects, like any other power project, must be financed. To be financeable, a power project should allocate risk in the most efficient way, so as to maximize return on investment. This paper examines the way in which various project documents can be structured to allocate most efficiently the technology and fuel risks unique to biomass projects, as well as the more typical risks, such as construction risk, permitting risk, expropriation risk, currency risk, country risk, sovereign risks, operating risks and credit risk. In addition, this paper summarizes the public financing sources and support that are available to assist in meeting the unique risk profiles of biomass projects. Specifically, it examines some of the principal multilateral and export credit agencies having involvement in this area. Finally, it examines potential strategies available to the developer of a biomass project for soliciting the involvement of, and negotiating with, local governments and public financing agencies. (author)

  20. Linking biomass fuel consumption and improve cooking stove: A study from Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Sohel, Md. Shawkat Islam; Rana, Md. Parvez; Akhter, Sayma

    2010-09-15

    The study determines the biomass fuel consumption pattern and environmental consequences of biomass fuel usage in the traditional and improve cooking stove. The introduction of improved cooking stove minimizes people's forest dependence by reducing the amount of fuelwood required to meet their household needs. Firewood was the most frequently used biomass fuel. It has been figured out that the incomplete combustion of biomass in the traditional cooking stove poses severe epidemiological consequences to human health and contributes to global warming. While improve cooking stove help to reduce such consequences.

  1. Traffic Behavior Recognition Using the Pachinko Allocation Model.

    Science.gov (United States)

    Huynh-The, Thien; Banos, Oresti; Le, Ba-Vui; Bui, Dinh-Mao; Yoon, Yongik; Lee, Sungyoung

    2015-07-03

    CCTV-based behavior recognition systems have gained considerable attention in recent years in the transportation surveillance domain for identifying unusual patterns, such as traffic jams, accidents, dangerous driving and other abnormal behaviors. In this paper, a novel approach for traffic behavior modeling is presented for video-based road surveillance. The proposed system combines the pachinko allocation model (PAM) and support vector machine (SVM) for a hierarchical representation and identification of traffic behavior. A background subtraction technique using Gaussian mixture models (GMMs) and an object tracking mechanism based on Kalman filters are utilized to firstly construct the object trajectories. Then, the sparse features comprising the locations and directions of the moving objects are modeled by PAMinto traffic topics, namely activities and behaviors. As a key innovation, PAM captures not only the correlation among the activities, but also among the behaviors based on the arbitrary directed acyclic graph (DAG). The SVM classifier is then utilized on top to train and recognize the traffic activity and behavior. The proposed model shows more flexibility and greater expressive power than the commonly-used latent Dirichlet allocation (LDA) approach, leading to a higher recognition accuracy in the behavior classification.

  2. Traffic Behavior Recognition Using the Pachinko Allocation Model

    Directory of Open Access Journals (Sweden)

    Thien Huynh-The

    2015-07-01

    Full Text Available CCTV-based behavior recognition systems have gained considerable attention in recent years in the transportation surveillance domain for identifying unusual patterns, such as traffic jams, accidents, dangerous driving and other abnormal behaviors. In this paper, a novel approach for traffic behavior modeling is presented for video-based road surveillance. The proposed system combines the pachinko allocation model (PAM and support vector machine (SVM for a hierarchical representation and identification of traffic behavior. A background subtraction technique using Gaussian mixture models (GMMs and an object tracking mechanism based on Kalman filters are utilized to firstly construct the object trajectories. Then, the sparse features comprising the locations and directions of the moving objects are modeled by PAMinto traffic topics, namely activities and behaviors. As a key innovation, PAM captures not only the correlation among the activities, but also among the behaviors based on the arbitrary directed acyclic graph (DAG. The SVM classifier is then utilized on top to train and recognize the traffic activity and behavior. The proposed model shows more flexibility and greater expressive power than the commonly-used latent Dirichlet allocation (LDA approach, leading to a higher recognition accuracy in the behavior classification.

  3. Biomass and leaf-level gas exchange characteristics of three African savanna C4 grass species under optimum growth conditions

    NARCIS (Netherlands)

    Mantlana, K.B.; Veenendaal, E.M.; Arneth, A.; Grispen, V.; Bonyongo, C.M.; Heitkönig, I.M.A.; Lloyd, J.

    2009-01-01

    C4 savanna grass species, Digitaria eriantha, Eragrostis lehmanniana and Panicum repens, were grown under optimum growth conditions with the aim of characterizing their above- and below-ground biomass allocation and the response of their gas exchange to changes in light intensity, CO2 concentration

  4. Evaluating the effect of alternative carbon allocation schemes in a land surface model (CLM4.5 on carbon fluxes, pools, and turnover in temperate forests

    Directory of Open Access Journals (Sweden)

    F. Montané

    2017-09-01

    Full Text Available How carbon (C is allocated to different plant tissues (leaves, stem, and roots determines how long C remains in plant biomass and thus remains a central challenge for understanding the global C cycle. We used a diverse set of observations (AmeriFlux eddy covariance tower observations, biomass estimates from tree-ring data, and leaf area index (LAI measurements to compare C fluxes, pools, and LAI data with those predicted by a land surface model (LSM, the Community Land Model (CLM4.5. We ran CLM4.5 for nine temperate (including evergreen and deciduous forests in North America between 1980 and 2013 using four different C allocation schemes: i. dynamic C allocation scheme (named "D-CLM4.5" with one dynamic allometric parameter, which allocates C to the stem and leaves to vary in time as a function of annual net primary production (NPP; ii. an alternative dynamic C allocation scheme (named "D-Litton", where, similar to (i, C allocation is a dynamic function of annual NPP, but unlike (i includes two dynamic allometric parameters involving allocation to leaves, stem, and coarse roots; iii.–iv. a fixed C allocation scheme with two variants, one representative of observations in evergreen (named "F-Evergreen" and the other of observations in deciduous forests (named "F-Deciduous". D-CLM4.5 generally overestimated gross primary production (GPP and ecosystem respiration, and underestimated net ecosystem exchange (NEE. In D-CLM4.5, initial aboveground biomass in 1980 was largely overestimated (between 10 527 and 12 897 g C m−2 for deciduous forests, whereas aboveground biomass accumulation through time (between 1980 and 2011 was highly underestimated (between 1222 and 7557 g C m−2 for both evergreen and deciduous sites due to a lower stem turnover rate in the sites than the one used in the model. D-CLM4.5 overestimated LAI in both evergreen and deciduous sites because the leaf C–LAI relationship in the model did not match the

  5. Evaluating the effect of alternative carbon allocation schemes in a land surface model (CLM4.5) on carbon fluxes, pools, and turnover in temperate forests

    Science.gov (United States)

    Montané, Francesc; Fox, Andrew M.; Arellano, Avelino F.; MacBean, Natasha; Alexander, M. Ross; Dye, Alex; Bishop, Daniel A.; Trouet, Valerie; Babst, Flurin; Hessl, Amy E.; Pederson, Neil; Blanken, Peter D.; Bohrer, Gil; Gough, Christopher M.; Litvak, Marcy E.; Novick, Kimberly A.; Phillips, Richard P.; Wood, Jeffrey D.; Moore, David J. P.

    2017-09-01

    How carbon (C) is allocated to different plant tissues (leaves, stem, and roots) determines how long C remains in plant biomass and thus remains a central challenge for understanding the global C cycle. We used a diverse set of observations (AmeriFlux eddy covariance tower observations, biomass estimates from tree-ring data, and leaf area index (LAI) measurements) to compare C fluxes, pools, and LAI data with those predicted by a land surface model (LSM), the Community Land Model (CLM4.5). We ran CLM4.5 for nine temperate (including evergreen and deciduous) forests in North America between 1980 and 2013 using four different C allocation schemes: i. dynamic C allocation scheme (named "D-CLM4.5") with one dynamic allometric parameter, which allocates C to the stem and leaves to vary in time as a function of annual net primary production (NPP); ii. an alternative dynamic C allocation scheme (named "D-Litton"), where, similar to (i), C allocation is a dynamic function of annual NPP, but unlike (i) includes two dynamic allometric parameters involving allocation to leaves, stem, and coarse roots; iii.-iv. a fixed C allocation scheme with two variants, one representative of observations in evergreen (named "F-Evergreen") and the other of observations in deciduous forests (named "F-Deciduous"). D-CLM4.5 generally overestimated gross primary production (GPP) and ecosystem respiration, and underestimated net ecosystem exchange (NEE). In D-CLM4.5, initial aboveground biomass in 1980 was largely overestimated (between 10 527 and 12 897 g C m-2) for deciduous forests, whereas aboveground biomass accumulation through time (between 1980 and 2011) was highly underestimated (between 1222 and 7557 g C m-2) for both evergreen and deciduous sites due to a lower stem turnover rate in the sites than the one used in the model. D-CLM4.5 overestimated LAI in both evergreen and deciduous sites because the leaf C-LAI relationship in the model did not match the observed leaf C

  6. Biomass power. Exploring the diffusion challenges in Spain

    International Nuclear Information System (INIS)

    Dinica, Valentina

    2009-01-01

    The use of biomass resources for power generation offers numerous benefits of interest for political decision-makers: fuel security, rural and industrial development, ecological benefits. In Spain, policy instruments have been used since 1980 to stimulate biomass power generation. However, the diffusion outcome by 2007 was very disappointing: only 525 MW. This paper argues that two factors lie at the core of this: the conceptualization of biomass resources by political decision-makers in the instruments used, and the desire that policy instruments be in line with market liberalization principles. These generated a persistent economic obstacle for biomass power generation, and impeded the development of markets for the supply of biomass resources. The policy learning regarding the heterogeneity of biomass resources, and the investors' expectations on risks, profitability and resource markets was very slow among political decision-makers. The paper contributes to the understanding of diffusion outcomes by proposing to analyse diffusion by means of five indicators: types of resources, technologies, developers, motivations to invest and project sizes. Besides, the paper shows the usefulness of investigating policy instruments in terms of their risk and profitability characteristics. This enables a better understanding of the diffusion patterns and outcomes. (author)

  7. Floristic structure and biomass distribution of a tropical seasonal rain forest in Xishuangbanna, southwest China

    Energy Technology Data Exchange (ETDEWEB)

    Shanmughavel, P.; Zheng Zheng; Sha Liqing; Cao Min [Chinese Academy of Sciences, Kunming (China). Dept. of Forest Ecology

    2001-07-01

    The aim of this research was to study the forest community structure, tree species diversity and biomass production of a tropical seasonal rain forest in Xishuangbanna, southwest China. The community structure showed a diversified species composition and supported many species of economic significance. This tropical rain forest in closely related to Malaysian forests. The biomass and its distribution were studied using standard regression analysis and the clear-cut method for shrubs and herbs. The total biomass was 360.9 t/ha and its allocation in different layers was: tree layer 352.5 t/ha, shrub layer 4.7 t/ha, liana 3.1 t/ha and herb layer 0.5 t/ha. Most of the biomass was concentrated in the trees: stem 241.2 t/ha, root 69.6 t/ha, branch 37.2 t/ha and leaves 4.3 t/ha. The DBH class allocation of the tree biomass was concentrated in the middle DBH class. The biomass of six DBH classes from 20 to 80 cm was 255.4 t/ha. There are twenty-six species with biomass over 0.5% of the total biomass of the tree layer, and three species with biomass over 5%, i.e., Pometia tomentosa, Barringtonia macrostachya (5.4%) and Terminalia myriocarpa (5.2%). Data on stem, branch, leaves and root of the individual tree species were used to develop regression models. D{sup 2}H was found to be the best estimator of the biomass in this tropical rain forest. However, higher biomass figures have been reported from tropical forests elsewhere e.g., 415-520 t/ha in the tropical forests of Cambodia, the tropical moist mixed dipterocarp forests, and the tropical moist logged moist evergreen-high, medium, and low yield forests of Sri Lanka. In some forests, lower accumulation of biomass was reported, e.g., 10-295 t/ha in the tropical moist forests of Bangladesh, the tropical moist dense forest of Cambodia, the tropical dry forests of India, the tropical moist forests of Peninsular-Malaysia, the tropical moist mixed dipterocarp forests of Sarawak-Malaysia, the tropical evergreen forests of

  8. Mechanisms driving carbon allocation in tropical rainforests: allometric constraints and environmental responses

    Science.gov (United States)

    Hofhansl, Florian; Schnecker, Jörg; Singer, Gabriel; Wanek, Wolfgang

    2014-05-01

    Tropical forest ecosystems play a major role in global water and carbon cycles. However, mechanisms of C allocation in tropical forests and their response to environmental variation are largely unresolved as, due to the scarcity of data, they are underrepresented in global syntheses of forest C allocation. Allocation of gross primary production to wood production exerts a key control on forest C residence time and biomass C turnover, and therefore is of special interest for terrestrial ecosystem research and earth system science. Here, we synthesize pantropical data from 105 old-growth rainforests to investigate relationships between climate (mean annual precipitation, mean annual temperature, dry season length and cloud cover), soil nutrient relations (soil N:P) and the partitioning of aboveground net primary production (ANPP) to wood production (WPart) using structural equation modelling. Our results show a strong increase of WPart with ANPP, pointing towards allometric scaling controls on WPart, with increasing light competition in more productive forests triggering greater ANPP allocation to wood production. ANPP itself was positively affected by mean annual temperature and soil N:P. Beyond these allometric controls on WPart we found direct environmental controls. WPart increased with dry season length in tropical montane rainforests and with mean annual precipitation in lowland tropical rainforests. We discuss different trade-offs between plant traits, such as community-wide changes along the wood economics spectrum, the leaf economics spectrum and the plant resource economics spectrum, as underlying mechanisms for direct climatic controls on WPart. We thereby provide new insights into mechanisms driving carbon allocation to WPart in tropical rainforests and show that low and high productive tropical rainforests may respond differently to projected global changes.

  9. Monitoring CO2emissions to gain a dynamic view of carbon allocation to arbuscular mycorrhizal fungi.

    Science.gov (United States)

    Slavíková, Renata; Püschel, David; Janoušková, Martina; Hujslová, Martina; Konvalinková, Tereza; Gryndlerová, Hana; Gryndler, Milan; Weiser, Martin; Jansa, Jan

    2017-01-01

    Quantification of carbon (C) fluxes in mycorrhizal plants is one of the important yet little explored tasks of mycorrhizal physiology and ecology. 13 CO 2 pulse-chase labelling experiments are increasingly being used to track the fate of C in these plant-microbial symbioses. Nevertheless, continuous monitoring of both the below- and aboveground CO 2 emissions remains a challenge, although it is necessary to establish the full C budget of mycorrhizal plants. Here, a novel CO 2 collection system is presented which allows assessment of gaseous CO 2 emissions (including isotopic composition of their C) from both belowground and shoot compartments. This system then is used to quantify the allocation of recently fixed C in mycorrhizal versus nonmycorrhizal Medicago truncatula plants with comparable biomass and mineral nutrition. Using this system, we confirmed substantially greater belowground C drain in mycorrhizal versus nonmycorrhizal plants, with the belowground CO 2 emissions showing large variation because of fluctuating environmental conditions in the glasshouse. Based on the assembled 13 C budget, the C allocation to the mycorrhizal fungus was between 2.3% (increased 13 C allocation to mycorrhizal substrate) and 2.9% (reduction of 13 C allocation to mycorrhizal shoots) of the plant gross photosynthetic production. Although the C allocation to shoot respiration (measured during one night only) did not differ between the mycorrhizal and nonmycorrhizal plants under our experimental conditions, it presented a substantial part (∼10%) of the plant C budget, comparable to the amount of CO 2 released belowground. These results advocate quantification of both above- and belowground CO 2 emissions in future studies.

  10. Plasma Treatments and Biomass Gasification

    Science.gov (United States)

    Luche, J.; Falcoz, Q.; Bastien, T.; Leninger, J. P.; Arabi, K.; Aubry, O.; Khacef, A.; Cormier, J. M.; Lédé, J.

    2012-02-01

    Exploitation of forest resources for energy production includes various methods of biomass processing. Gasification is one of the ways to recover energy from biomass. Syngas produced from biomass can be used to power internal combustion engines or, after purification, to supply fuel cells. Recent studies have shown the potential to improve conventional biomass processing by coupling a plasma reactor to a pyrolysis cyclone reactor. The role of the plasma is twofold: it acts as a purification stage by reducing production of tars and aerosols, and simultaneously produces a rich hydrogen syngas. In a first part of the paper we present results obtained from plasma treatment of pyrolysis oils. The outlet gas composition is given for various types of oils obtained at different experimental conditions with a pyrolysis reactor. Given the complexity of the mixtures from processing of biomass, we present a study with methanol considered as a model molecule. This experimental method allows a first modeling approach based on a combustion kinetic model suitable to validate the coupling of plasma with conventional biomass process. The second part of the paper is summarizing results obtained through a plasma-pyrolysis reactor arrangement. The goal is to show the feasibility of this plasma-pyrolysis coupling and emphasize more fundamental studies to understand the role of the plasma in the biomass treatment processes.

  11. EnerGEO biomass pilot

    International Nuclear Information System (INIS)

    Tum, M.; Guenther, K.P.; McCallum, I.; Balkovic, J.; Khabarov, N.; Kindermann, G.; Leduc, S.; Biberacher, M.

    2013-01-01

    In the framework of the EU FP7 project EnerGEO (Earth Observations for Monitoring and Assessment of the Environmental Impact of Energy Use) sustainable energy potentials for forest and agricultural areas were estimated by applying three different model approaches. Firstly, the Biosphere Energy Transfer Hydrology (BETHY/DLR) model was applied to assess agricultural and forest biomass increases on a regional scale with the extension to grassland. Secondly, the EPIC (Environmental Policy Integrated Climate) - a cropping systems simulation model - was used to estimate grain yields on a global scale and thirdly the Global Forest Model (G4M) was used to estimate global woody biomass harvests and stock. The general objective of the biomass pilot is to implement the observational capacity for using biomass as an important current and future energy resource. The scope of this work was to generate biomass energy potentials for locations on the globe and to validate these data. Therefore, the biomass pilot was focused to use historical and actual remote sensing data as input data for the models. For validation purposes, forest biomass maps for 1987 and 2002 for Germany (Bundeswaldinventur (BWI-2)) and 2001 and 2008 for Austria (Austrian Forest Inventory (AFI)) were prepared as reference. (orig.)

  12. Surveillance of C-Allocation in Microalgal Cells

    Directory of Open Access Journals (Sweden)

    Heiko Wagner

    2014-06-01

    Full Text Available When microalgae are exposed to changing environmental conditions, e.g., light-dark cycles or oscillations in nutrient availability (CO2, nitrogen, phosphate or silicate they respond with metabolic changes in the carbon allocation pattern. Short time regulations in the time range of few seconds to minutes can be mirrored best by mass spectroscopy based metabolomics. However, these snap shots do not reflect the alterations in the carbon flow to the cellular macromolecules like protein, carbohydrate or lipid. In this review it is shown how the combination of FTIR spectroscopy and Chla-in-vivo-fluorescence based electron transport rates can reveal changes in the metabolic flux rates of carbon during a shift of the environmental conditions. The review will demonstrate in which time range FTIR spectroscopy can deliver significant information and how FTIR spectroscopy data can synergistically support metabolome analysis by mass-spectroscopy.

  13. Scheduling Patients’ Appointments: Allocation of Healthcare Service Using Simulation Optimization

    Directory of Open Access Journals (Sweden)

    Ping-Shun Chen

    2015-01-01

    Full Text Available In the service industry, scheduling medical procedures causes difficulties for both patients and management. Factors such as fluctuations in customer demand and service time affect the appointment scheduling systems’ performance in terms of, for example, patients’ waiting time, idle time of resources, and total cost/profits. This research implements four appointment scheduling policies, i.e., constant arrival, mixed patient arrival, three-section pattern arrival, and irregular arrival, in an ultrasound department of a hospital in Taiwan. By simulating the four implemented policies’ optimization procedures, optimal or near-optimal solutions can be obtained for patients per arrival, patients’ inter-arrival time, and the number of the time slots for arrived patients. Furthermore, three objective functions are tested, and the results are discussed. The managerial implications and discussions are summarized to demonstrate how outcomes can be useful for hospital managers seeking to allocate their healthcare service capacities.

  14. A staff allocation model for mental health facilities.

    Science.gov (United States)

    Lyons, J P; Young, J P

    1976-01-01

    This article describes a model for allocating staff within a large psychiatric hospital. The model provides an objective framework within which one can test alternative staff operating policies before making critical decisions concerning the employment of one category of personnel as opposed to another. It is based on objective data describing patient needs and staff functioning patterns, rather than subjective opinions concerning staff deployment. Besides being useful for the short-term deployment of staff and budgetary resources, it can also be used as a long-range planning tool for testing modifications in policy decisions and budget proposals. The algorithm employed, mixed-integer linear programming, is readily available; computer costs and running time are relatively minimal.

  15. Effect of microbial enzyme allocation strategies on stoichiometry of soil organic matter (SOM) decomposition

    Science.gov (United States)

    Wutzler, Thomas

    2014-05-01

    We explored different strategies of soil microbial community to invest resources into extracellular enzymes by conceptual modelling. Similar to the EEZY model by Moorhead et al. (2012), microbial community can invest into two separate pools of enzymes that depolymerize two different SOM pools. We show that with assuming that a fixed fraction of substrate uptake is allocated to enzymes, the microbial dynamics decouples from decomposition dynamics. We propose an alternative formulation where investment into enzymes is proportional to microbial biomass. Next, we show that the strategy of optimizing stoichiometry of decomposition flux according to microbial biomass stoichiometry yield less microbial growth than the strategy of optimizing revenue of the currently limiting element. However, both strategies result in better usage of the resources, i.e. less C overflow or N mineralization, than the strategy of equal allocation to both enzymes. Further, we discuss effects of those strategies on decomposition of SOM and priming at different time scales and discuss several abstractions from the detailed model dynamics for usage in larger scale models.

  16. Bearings for the biomass boom

    Energy Technology Data Exchange (ETDEWEB)

    MacQueen, Duncan

    2011-03-15

    Biomass energy is booming –– more than two billion people depend on biomass for their energy and the International Energy Agency predicts that biomass' share of the global energy supply will treble by 2050. But in many developing countries it is still regarded as a traditional and dirty solution that is often criminalised, unsustainable and poorly paid. A more sophisticated approach that legalises and secures sustainable production by and for local people could help improve energy security, cut carbon emissions, protect forests and reduce poverty.

  17. Biomass combustion gas turbine CHP

    Energy Technology Data Exchange (ETDEWEB)

    Pritchard, D.

    2002-07-01

    This report summarises the results of a project to develop a small scale biomass combustor generating system using a biomass combustor and a micro-gas turbine indirectly fired via a high temperature heat exchanger. Details are given of the specification of commercially available micro-turbines, the manufacture of a biomass converter, the development of a mathematical model to predict the compatibility of the combustor and the heat exchanger with various compressors and turbines, and the utilisation of waste heat for the turbine exhaust.

  18. IV. International Slovak Biomass Forum

    International Nuclear Information System (INIS)

    2004-03-01

    The publication has been set up as proceedings of the conference dealing with use of biomass for energy production. The main conference topics are focused on the following scopes: Session 1: Strategies, politics, legislation tools, implementation issues; Session 2: Bioenergy market and business; Session 3: Biomass resources and fuel production; Session 4: Combustion and boiler system, technology; Session 5: Utilisation of biomass, practical examples (CHP, WWTP, DH, Central heating, Stakeholders); Session 6: Application of R + D in praxis in the short term horizont. In these proceedings 44 contributions are included

  19. Plankton composition and biomass development

    DEFF Research Database (Denmark)

    Jakobsen, H.H.; Jepsen, P.M.; Blanda, E.

    2016-01-01

    Plankton food web dynamics were studied during a complete production season in a semi-intensive land-based facility for rearing of turbot (Scophthalmus maximus) larvae. The production season was divided into three production cycles of 3–5 weeks. Phytoplankton biomass (using chlorophyll a as biomass...... proxy) peaked in each production cycle. However, the maximum biomass decreased from spring (18 μg chlorophyll a L−1) to fall (ca. 7 μg chlorophyll a L−1), simultaneous with a decline in the concentration of dissolved nitrogen in the inoculating water. During the three production cycles, we observed...

  20. Availability of biomass for energy production. GRAIN: Global Restrictions on biomass Availability for Import to the Netherlands

    International Nuclear Information System (INIS)

    Lysen, E.H.

    2000-08-01

    great opportunities for a sustainable supply of energy and materials, but on the other hand it bears large ecological and economical risks, such as deforestation and competition with food production. It is therefore of the utmost importance to formulate minimum requirements for large-scale bio-energy projects and international trade in biomass energy. For international trade in biomass energy it is important to identify regions with a future biomass energy surplus, related to their own energy consumption. Exporting this surplus would have to be done as efficiently as possible, with regard to CO2 emission reduction. Transatlantic shipments of wood have to be balanced against local conversion and shipping the fuel. An important recommendation to the Netherlands government about the possible future import of biomass is therefore: increase the knowledge and insights in the possible consequences of large scale import of biomass energy. This can be done by setting up a limited number of pilot projects for the trade in bio-energy, and by monitoring these projects very carefully, supported by research activities. Such pilot projects can also provide a better understanding in how broad the support for these activities is, both in the Netherlands as well in exporting countries. In the long run much more knowledge and information is required about which regions would be most suited for a sustainable production and trade in biomass energy. It will be necessary to develop and introduce a 'FSC' type mark for biomass-based energy carriers. There are still a number of crucial research questions in areas such as: economic drivers of land use, competition of biomass with other land uses, and competition with other sources of energy and materials. These interactions need to be studied at local/regional level, taking into account the effect of technological and economical changes in time. In addition there are complex questions in the field of optimising the allocation of biomass resources

  1. Biomass catalysis and solvents; Biomasse catalyse et solvants

    Energy Technology Data Exchange (ETDEWEB)

    Pioch, D. [CIRAD-AMIS, programme Agro-Alimentaire, 34 - Montpellier (France); Pouilloux, Y.; Barrault, J. [Centre National de la Recherche Scientifique (CNRS UMR 6503), ESIP, Lab. de Catalyse en Chimie Organique, 86 - Poitiers (France)] [and others

    2000-07-01

    How to develop new technics and products and at the same time to respect the environment? The biomass seems to be an interesting domain in this framework and this document allows the selection of performing products obtain by biomass. Among these products the solvents economic and environmental advantages or consequences are discussed. A great part is also devoted to the voc emissions, bound to the solvents.

  2. Energy densification of animal waste lignocellulose biomass and raw biomass

    Directory of Open Access Journals (Sweden)

    G. Pahla

    2017-12-01

    Full Text Available The need to reduce carbon emissions has encouraged more research into use of biomass energy in place of coal. Biomass is carbon neutral; its use can therefore lower net emissions. Biomass can be upgraded to a fuel similar to coal by torrefaction. Different biomass have been torrefied but there is limited research in possible use of lignocellulose biomass from animal waste. This study aims to compare extent of energy densification of torrefied cow dung, corn cob and pine wood. They were dried, ground and sieved. Proximate and ultimate analysis was conducted. The samples were then torrefied at 200, 250 and 300 °C at 10 °C/min for 40 min. The resulting biochar were characterized using mass yield, higher heating value, energy yield and density. Biochar obtained at 250 °C were analyzed for elemental composition. Results were compared to Anglo bituminous coal and other torrefied biomass in literature. Corn cob and pine wood reached a maximum of 25.98 MJ/kg and 20.90 MJ/kg in heating value respectively whilst cow dung only increased to a maximum of 18.60 MJ/kg. Increase in heating value for corn cob was attributed to reduction in oxygen due to release of volatiles as well as water. This lowered the O/C ratio thereby densifying the fuel. The O/C and H/C ratio for corncob and wood moved towards that of bituminous coal unlike that of cow dung. Cow dung had a high inorganic composition so its heating value could not be upgraded as much as the other 2 biomass. Its use as a torrefaction raw material was therefore discouraged. Keywords: Torrefaction, Biomass, Temperature, Cow dung, Corn cobs, Pine wood

  3. Browsing affects intra-ring carbon allocation in species with contrasting wood anatomy.

    Science.gov (United States)

    Palacio, S; Paterson, E; Sim, A; Hester, A J; Millard, P

    2011-02-01

    Current knowledge on tree carbon (C) allocation to wood is particularly scarce in plants subjected to disturbance factors, such as browsing, which affects forest regeneration worldwide and has an impact on the C balance of trees. Furthermore, quantifying the degree to which tree rings are formed from freshly assimilated vs. stored carbohydrates is highly relevant for our understanding of tree C allocation. We used (13)C labelling to quantify seasonal allocation of stored C to wood formation in two species with contrasting wood anatomy: Betula pubescens Ehrh. (diffuse-porous) and Quercus petraea [Matt.] Liebl. (ring-porous). Clipping treatments (66% shoot removal, and unclipped) were applied to analyse the effect of browsing on C allocation into tree rings, plus the effects on tree growth, architecture, ring width and non-structural carbohydrates (NSCs). The relative contribution of stored C to wood formation was greater in the ring-porous (55-70%) than in the diffuse-porous species (35-60%), although each species followed different seasonal trends. Clipping did not cause a significant depletion of C stores in either species. Nonetheless, a significant increase in the proportion of stored C allocated to earlywood growth was observed in clipped birches, and this could be explained through changes in tree architecture after clipping. The size of C pools across tree species seems to be important in determining the variability of seasonal C allocation patterns to wood and their sensibility to disturbances such as browsing. Our results indicate that the observed changes in C allocation to earlywood in birch were not related to variations in the amount or concentration of NSC stores, but to changes in the seasonal availability of recently assimilated C caused by modifications in tree architecture after browsing.

  4. Using contests to allocate pollution rights

    International Nuclear Information System (INIS)

    MacKenzie, Ian A.; Hanley, Nick; Kornienko, Tatiana

    2009-01-01

    In this paper we advocate a new initial allocation mechanism for a tradable pollution permit market. We outline a Permit Allocation Contest (PAC) that distributes permits to firms based on their rank relative to other firms. This ranking is achieved by ordering firms based on an observable 'external action' where the external action is an activity or characteristic of the firm that is independent of their choice of emissions in the tradable permit market. We argue that this mechanism has a number of benefits over auctioning and grandfathering. Using this mechanism efficiently distributes permits, allows for the attainment of a secondary policy objective and has the potential to be more politically appealing than existing alternatives.

  5. Time-allocation matching between punishing situations.

    Science.gov (United States)

    Deluty, M Z; Church, R M

    1978-03-01

    In the presence and absence of white noise, response-independent aversive events were delivered to rats according to several variable-time electric-shock schedules. The animals could switch from the noise component to the no-noise component and vice versa by making a single lever-press response. If the schedule in one component was not in operation when the animal was in the other component, the proportion of time allocated to one component equalled or matched the proportion of obtained punishers in the other component. If both schedules were always in operation, minimizing tended to occur: the animals allocated almost all of their time to the component having the lower shock rate. An analysis of these results, in terms of the expected time until an aversive event, is presented.

  6. Fund Allocation in Complex Rehabilitation Programs

    Directory of Open Access Journals (Sweden)

    Tarek Hegazy

    2013-12-01

    Full Text Available Civil Infrastructure assets require continuous renewal actions to sustain their operability and safety. Allocating limited renewal funds amongst numerous building components, however, represents a large-scale optimization problem and earlier efforts utilized genetic algorithms (GAs to optimize medium size problems yet exhibit steep performance degradation as problem size increases. In this research, after experimenting with various approaches of segmenting a large problem into multiple smaller sub-problems, clustered segmentation proved to be the most promising. The paper discusses the underlying life cycle analysis model, the various segmentation methods, and the optimization results using the improved GAs + clustered segmentation, which proved to be able to optimize asset renewals for 50,000 components with no noticeable performance degradation. The proposed method is simple and logical, and can be used on variety of asset types to improve infrastructure fund allocation. Future extension of this research is then highlighted.

  7. Risk allocation in independent power supply contracts

    International Nuclear Information System (INIS)

    Willrich, M.; Campbell, W.L.

    1992-01-01

    Congress has made significant progress in recent months toward amending the Public Utility Holding Company Act of 1935 (PUHCA). The purposes of such amendment are to broaden power supply options for electric utilities and expand competition in whole-sale power generation markets. PUHCA reform is an integral part of President Bush's National Energy Strategy and has been included in legislation pending in both Houses of Congress. Congress will, hopefully, approve energy legislation that includes PUHCA reform before it adjourns this year. PUHCA reform has, however, stimulated heated debate within the power industry itself as well as among various consumer interest groups. One important issue in the public debate concerns risk allocation. If PUHCA is reformed, will risk be allocated efficiently and equitably between independent power producers and electric utility buyers? This article addresses that important question

  8. Traffic resource allocation for complex networks

    International Nuclear Information System (INIS)

    Ling Xiang; Long Jian-Cheng; Ding Jian-Xun; Shi Qin; Hu Mao-Bin

    2013-01-01

    In this paper, an optimal resource allocation strategy is proposed to enhance traffic dynamics in complex networks. The network resources are the total node packet-delivering capacity and the total link bandwidth. An analytical method is developed to estimate the overall network capacity by using the concept of efficient betweenness (ratio of algorithmic betweenness and local processing capacity). Three network structures (scale-free, small-world, and random networks) and two typical routing protocols (shortest path protocol and efficient routing protocol) are adopted to demonstrate the performance of the proposed strategy. Our results show that the network capacity is reversely proportional to the average path length for a particular routing protocol and the shortest path protocol can achieve the largest network capacity when the proposed resource allocation strategy is adopted. (interdisciplinary physics and related areas of science and technology)

  9. Register allocation for fine grain threads on

    Directory of Open Access Journals (Sweden)

    D.C. Kiran

    2017-01-01

    Full Text Available A multicore processor has multiple processing cores on the same chip. Unicore and multicore processors are architecturally different. Since individual instructions are needed to be scheduled onto one of the available cores, it effectively decreases the number of instructions executed on the individual core of a multicore processor. As each core of a multicore processor has a private register file, it results in reduced register pressure. To effectively utilize the potential benefits of the multicore processor, the sequential program must be split into small parallel regions to be run on different cores, and the register allocation must be done for each of these cores. This article discusses register allocating heuristics for fine grained threads which can be scheduled on multiple cores. Spills are computed and its effect on speed-up, power consumption and performance per power is compared for a RAW benchmark suite.

  10. The dynamics of farm land allocation

    DEFF Research Database (Denmark)

    Arnberg, Søren; Hansen, Lars Gårn

    This study develops a dynamic multi-output model of farmers’ crop allocation decisions that allows estimation of both short-run and long-run adjustments to a wide array of economic incentives. The method can be used to inform decision-makers about a number of issues including agricultural policy...... reform and environmental regulation. The model allows estimation of dynamic effects relating to price expectations adjustment, investment lags and crop rotation constraints. Estimation is based on micro-panel data from Danish farmers that includes acreage, output and variable input utilisation...... at the crop level. Results indicate that there are substantial differences between the shortrun and long-run land allocation behaviour of Danish farmers and that there are substantial differences in the time lags associated with different crops. Since similar farming conditions are found in northern Europe...

  11. Multiobjective optimal allocation problem with probabilistic non ...

    African Journals Online (AJOL)

    user

    h a,c , j k and h. N are all positive constants. If the budget of the survey is fixed in advance, say, C , then the multivariate allocation problem is stated to minimize the variances for various characters for a desired precision as the following p convex programming problems. p,..., j .L,..., h;N n and. C c nc to. Subject. N a n a. V.Min.

  12. Allocating nuclear power plant costs: an extension

    International Nuclear Information System (INIS)

    Bierman, H. Jr.

    1984-01-01

    The author modifies and extends the argument presented in the September 22, 1983 issue by Richard E. Nellis for using economic depreciation to allocate nuclear power plant costs. The two goals of his model are to charge constant real costs to consumers and to provide a fair return of .125 to investors in each period. The addition of other objectives requires further modification of the model since the schedule of revenues that are deemed to be optimum defines the depreciation schedule. 1 table

  13. Student Time Allocation and Educational Production Functions

    OpenAIRE

    Massimiliano BRATTI; Stefano STAFFOLANI

    2002-01-01

    In this paper we investigate the effect of lecture attendance and self-study on undergraduate students' academic performance. We first introduce a simple theoretical model in which students decide the optimal allocation of their time between lecture attendance, self-study and leisure. Under some assumptions, we find a positive relationship between lecture attendance and time devoted to self-study in each course, from which we infer that estimates of the elasticity of student performance with ...

  14. Optimal allocation of trend following strategies

    Science.gov (United States)

    Grebenkov, Denis S.; Serror, Jeremy

    2015-09-01

    We consider a portfolio allocation problem for trend following (TF) strategies on multiple correlated assets. Under simplifying assumptions of a Gaussian market and linear TF strategies, we derive analytical formulas for the mean and variance of the portfolio return. We construct then the optimal portfolio that maximizes risk-adjusted return by accounting for inter-asset correlations. The dynamic allocation problem for n assets is shown to be equivalent to the classical static allocation problem for n2 virtual assets that include lead-lag corrections in positions of TF strategies. The respective roles of asset auto-correlations and inter-asset correlations are investigated in depth for the two-asset case and a sector model. In contrast to the principle of diversification suggesting to treat uncorrelated assets, we show that inter-asset correlations allow one to estimate apparent trends more reliably and to adjust the TF positions more efficiently. If properly accounted for, inter-asset correlations are not deteriorative but beneficial for portfolio management that can open new profit opportunities for trend followers. These concepts are illustrated using daily returns of three highly correlated futures markets: the E-mini S&P 500, Euro Stoxx 50 index, and the US 10-year T-note futures.

  15. Resource allocation criteria in a hospital.

    Science.gov (United States)

    Bodina, A; Pavan, A; Castaldi, S

    2017-06-01

    Allocate fixed resources among competing users is a challenge in terms of hospital management in order to obtain the best performance considering strategic objectives. In order to address this need, a system of evaluation in an important research and teaching hospital was designed. This study describes resource allocation criteria in a hospital focusing on the evaluation system and its developed application methodology. The indicator system allows the strategic management to rapidly detect the priorities in the evaluations of the Strategic, Organizational, Managerial, Economic, Research and Qualitative conditions of each unit. The chosen indicators are expressed with three numerical values, (1 indicating critical status, 2 acceptable conditions and 3 a good operational situation). The adopted evaluation system considered different thematic areas: Strategic, Organizational, Managerial, Economic, Research and Qualitative. In order to define each area, 3 fields of evaluation have been chosen. The indicators have been structured according to a pyramid system allowing creating a single indicator for each area for each unit. Furthermore, a single indicator has been fixed in order to facilitate a first consideration on whether to carry out or not closer examinations of the most critical units. This manuscript describes an attempt to define objective criteria for the allocation of scarce resources in order to achieve the hospital's strategic objectives. The indicators identified allow to obtain an overall score for each unit, which allows the management to prioritize the needs.

  16. Irrational time allocation in decision-making.

    Science.gov (United States)

    Oud, Bastiaan; Krajbich, Ian; Miller, Kevin; Cheong, Jin Hyun; Botvinick, Matthew; Fehr, Ernst

    2016-01-13

    Time is an extremely valuable resource but little is known about the efficiency of time allocation in decision-making. Empirical evidence suggests that in many ecologically relevant situations, decision difficulty and the relative reward from making a correct choice, compared to an incorrect one, are inversely linked, implying that it is optimal to use relatively less time for difficult choice problems. This applies, in particular, to value-based choices, in which the relative reward from choosing the higher valued item shrinks as the values of the other options get closer to the best option and are thus more difficult to discriminate. Here, we experimentally show that people behave sub-optimally in such contexts. They do not respond to incentives that favour the allocation of time to choice problems in which the relative reward for choosing the best option is high; instead they spend too much time on problems in which the reward difference between the options is low. We demonstrate this by showing that it is possible to improve subjects' time allocation with a simple intervention that cuts them off when their decisions take too long. Thus, we provide a novel form of evidence that organisms systematically spend their valuable time in an inefficient way, and simultaneously offer a potential solution to the problem. © 2016 The Author(s).

  17. Resource allocation models of auditory working memory.

    Science.gov (United States)

    Joseph, Sabine; Teki, Sundeep; Kumar, Sukhbinder; Husain, Masud; Griffiths, Timothy D

    2016-06-01

    Auditory working memory (WM) is the cognitive faculty that allows us to actively hold and manipulate sounds in mind over short periods of time. We develop here a particular perspective on WM for non-verbal, auditory objects as well as for time based on the consideration of possible parallels to visual WM. In vision, there has been a vigorous debate on whether WM capacity is limited to a fixed number of items or whether it represents a limited resource that can be allocated flexibly across items. Resource allocation models predict that the precision with which an item is represented decreases as a function of total number of items maintained in WM because a limited resource is shared among stored objects. We consider here auditory work on sequentially presented objects of different pitch as well as time intervals from the perspective of dynamic resource allocation. We consider whether the working memory resource might be determined by perceptual features such as pitch or timbre, or bound objects comprising multiple features, and we speculate on brain substrates for these behavioural models. This article is part of a Special Issue entitled SI: Auditory working memory. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. A Channel Allocation Mechanism for Cellular Networks

    Directory of Open Access Journals (Sweden)

    Chi-Hua Chen

    2017-04-01

    Full Text Available In cellular networks, call blocking causes lower customer satisfaction and economic loss. Therefore, the channel allocation for call block avoidance is an important issue. This study proposes a mechanism that considers the real-time traffic information (e.g., traffic flow and vehicle speed and the user behavior (e.g., call inter-arrival time and call holding time to analyze the adaptable number of communication calls in the specific cell for channel allocation. In experiments about call block probabilities (CBP, this study simulated two cases that are the situations of the whole day and traffic accident. The simulation results show that all CBPs in the scenario of whole day are less than 21.5% by using the proposed mechanism, which is better than using the static channel allocation (SCA mechanism. Moreover, all CBPs in the scenario of traffic accidents are less than 16.5% by using the proposed mechanism, which is better than using the SCA mechanism. Therefore, the proposed mechanism can decrease the number of CBPs effectively.

  19. Legal briefing: organ donation and allocation.

    Science.gov (United States)

    Pope, Thaddeus Mason

    2010-01-01

    This issue's "Legal Briefing" column covers legal developments pertaining to organ donation and allocation. This topic has been the subject of recent articles in JCE. Organ donation and allocation have also recently been the subjects of significant public policy attention. In the past several months, legislatures and regulatory agencies across the United States and across the world have changed, or considered changing, the methods for procuring and distributing human organs for transplantation. Currently, in the U.S., more than 100,000 persons are waiting for organ transplantation. In China, more than 1.5 million people are waiting. Given the chronic shortage of available organs (especially kidneys and livers) relative to demand, the primary focus of most legal developments has been on increasing the rate of donation. These and related developments are usefully divided into the following 12 topical categories: 1. Revised Uniform Anatomical Gift Act. 2. Presumed Consent and Opt-Out. 3. Mandated Choice. 4. Donation after Cardiac Death. 5. Payment and Compensation. 6. Donation by Prisoners. 7. Donor Registries. 8. Public Education. 9. Other Procurement Initiatives. 10. Lawsuits and Liability. 11. Trafficking and Tourism. 12. Allocation and Distribution.

  20. Zooplankton structure and vertical migration: Using acoustics and biomass to compare stratified and mixed fjord systems

    Science.gov (United States)

    Díaz-Astudillo, Macarena; Cáceres, Mario A.; Landaeta, Mauricio F.

    2017-09-01

    The patterns of abundance, composition, biomass and vertical migration of zooplankton in short-time scales (ADCP device mounted on the hull of a ship were used to obtain vertical profiles of current velocity data and intensity of the backscattered acoustic signal, which was used to study the migratory strategies and to relate the echo intensity with zooplankton biomass. Repeated vertical profiles of temperature, salinity and density were obtained with a CTD instrument to describe the density patterns during both experiments. Zooplankton were sampled every 3 h using a Bongo net to determine abundance, composition and biomass. Migrations were diel in the stratified station, semi-diel in the mixed station, and controlled by light in both locations, with large and significant differences in zooplankton abundance and biomass between day and night samples. No migration pattern associated with the effect of tides was found. The depth of maximum backscatter strength showed differences of approximately 30 m between stations and was deeper in the mixed station. The relation between mean volume backscattering strength (dB) computed from echo intensity and log10 of total dry weight (mg m-3) of zooplankton biomass was moderate but significant in both locations. Biomass estimated from biological samples was higher in the mixed station and determined by euphausiids. Copepods were the most abundant group in both stations. Acoustic methods were a useful technique to understand the detailed patterns of migratory strategies of zooplankton and to help estimate zooplankton biomass and abundance in the inner waters of southern Chile.