WorldWideScience

Sample records for above-ground nuclear tests

  1. Nuclear Reactor Monitoring With an Above Ground Antineutrino Detector

    Classen, Timothy

    2011-04-01

    Technology to detect νe 's emitted from nuclear reactors has existed for more than 50 years. This technology has been used in a range of experiments probing the neutrino parameter space. A continuing effort has been made at LLNL to test whether this technology may be used for a more practical purpose, the monitoring of nuclear reactors with a focus on safeguarding dangerous nuclear materials. As part of this role a new detector is being developed for deployment above ground at the Point Lepreau Nuclear Generating Station in New Brunswick Canada. The detector will observe a reactor core through a full start-up phase, to determine how well it can measure changes in nuclear fuel composition. This talk will focus on the challenges of the experiment, and how the techniques of fundamental neutrino research may be used to overcome them. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  2. Above-ground antineutrino detection for nuclear reactor monitoring

    Antineutrino monitoring of nuclear reactors has been demonstrated many times (Klimov et al., 1994 [1]; Bowden et al., 2009 [2]; Oguri et al., 2014 [3]), however the technique has not as of yet been developed into a useful capability for treaty verification purposes. The most notable drawback is the current requirement that detectors be deployed underground, with at least several meters-water-equivalent of shielding from cosmic radiation. In addition, the deployment of liquid-based detection media presents a challenge in reactor facilities. We are currently developing a detector system that has the potential to operate above ground and circumvent deployment problems associated with a liquid detection media: the system is composed of segments of plastic scintillator surrounded by 6LiF/ZnS:Ag. ZnS:Ag is a radio-luminescent phosphor used to detect the neutron capture products of 6Li. Because of its long decay time compared to standard plastic scintillators, pulse-shape discrimination can be used to distinguish positron and neutron interactions resulting from the inverse beta decay (IBD) of antineutrinos within the detector volume, reducing both accidental and correlated backgrounds. Segmentation further reduces backgrounds by identifying the positron's annihilation gammas, a signature that is absent for most correlated and uncorrelated backgrounds. This work explores different configurations in order to maximize the size of the detector segments without reducing the intrinsic neutron detection efficiency. We believe that this technology will ultimately be applicable to potential safeguards scenarios such as those recently described by Huber et al. (2014) [4,5

  3. Above-ground antineutrino detection for nuclear reactor monitoring

    Sweany, M.; Brennan, J.; Cabrera-Palmer, B.; Kiff, S.; Reyna, D.; Throckmorton, D.

    2015-01-01

    Antineutrino monitoring of nuclear reactors has been demonstrated many times (Klimov et al., 1994 [1]; Bowden et al., 2009 [2]; Oguri et al., 2014 [3]), however the technique has not as of yet been developed into a useful capability for treaty verification purposes. The most notable drawback is the current requirement that detectors be deployed underground, with at least several meters-water-equivalent of shielding from cosmic radiation. In addition, the deployment of liquid-based detection media presents a challenge in reactor facilities. We are currently developing a detector system that has the potential to operate above ground and circumvent deployment problems associated with a liquid detection media: the system is composed of segments of plastic scintillator surrounded by {sup 6}LiF/ZnS:Ag. ZnS:Ag is a radio-luminescent phosphor used to detect the neutron capture products of {sup 6}Li. Because of its long decay time compared to standard plastic scintillators, pulse-shape discrimination can be used to distinguish positron and neutron interactions resulting from the inverse beta decay (IBD) of antineutrinos within the detector volume, reducing both accidental and correlated backgrounds. Segmentation further reduces backgrounds by identifying the positron's annihilation gammas, a signature that is absent for most correlated and uncorrelated backgrounds. This work explores different configurations in order to maximize the size of the detector segments without reducing the intrinsic neutron detection efficiency. We believe that this technology will ultimately be applicable to potential safeguards scenarios such as those recently described by Huber et al. (2014) [4,5].

  4. Standard practice for guided wave testing of above ground steel pipework using piezoelectric effect transduction

    American Society for Testing and Materials. Philadelphia

    2011-01-01

    1.1 This practice provides a procedure for the use of guided wave testing (GWT), also previously known as long range ultrasonic testing (LRUT) or guided wave ultrasonic testing (GWUT). 1.2 GWT utilizes ultrasonic guided waves, sent in the axial direction of the pipe, to non-destructively test pipes for defects or other features by detecting changes in the cross-section and/or stiffness of the pipe. 1.3 GWT is a screening tool. The method does not provide a direct measurement of wall thickness or the exact dimensions of defects/defected area; an estimate of the defect severity however can be provided. 1.4 This practice is intended for use with tubular carbon steel or low-alloy steel products having Nominal Pipe size (NPS) 2 to 48 corresponding to 60.3 to 1219.2 mm (2.375 to 48 in.) outer diameter, and wall thickness between 3.81 and 25.4 mm (0.15 and 1 in.). 1.5 This practice covers GWT using piezoelectric transduction technology. 1.6 This practice only applies to GWT of basic pipe configuration. This inc...

  5. Testing the generality of above-ground biomass allometry across plant functional types at the continent scale.

    Paul, Keryn I; Roxburgh, Stephen H; Chave, Jerome; England, Jacqueline R; Zerihun, Ayalsew; Specht, Alison; Lewis, Tom; Bennett, Lauren T; Baker, Thomas G; Adams, Mark A; Huxtable, Dan; Montagu, Kelvin D; Falster, Daniel S; Feller, Mike; Sochacki, Stan; Ritson, Peter; Bastin, Gary; Bartle, John; Wildy, Dan; Hobbs, Trevor; Larmour, John; Waterworth, Rob; Stewart, Hugh T L; Jonson, Justin; Forrester, David I; Applegate, Grahame; Mendham, Daniel; Bradford, Matt; O'Grady, Anthony; Green, Daryl; Sudmeyer, Rob; Rance, Stan J; Turner, John; Barton, Craig; Wenk, Elizabeth H; Grove, Tim; Attiwill, Peter M; Pinkard, Elizabeth; Butler, Don; Brooksbank, Kim; Spencer, Beren; Snowdon, Peter; O'Brien, Nick; Battaglia, Michael; Cameron, David M; Hamilton, Steve; McAuthur, Geoff; Sinclair, Jenny

    2016-06-01

    Accurate ground-based estimation of the carbon stored in terrestrial ecosystems is critical to quantifying the global carbon budget. Allometric models provide cost-effective methods for biomass prediction. But do such models vary with ecoregion or plant functional type? We compiled 15 054 measurements of individual tree or shrub biomass from across Australia to examine the generality of allometric models for above-ground biomass prediction. This provided a robust case study because Australia includes ecoregions ranging from arid shrublands to tropical rainforests, and has a rich history of biomass research, particularly in planted forests. Regardless of ecoregion, for five broad categories of plant functional type (shrubs; multistemmed trees; trees of the genus Eucalyptus and closely related genera; other trees of high wood density; and other trees of low wood density), relationships between biomass and stem diameter were generic. Simple power-law models explained 84-95% of the variation in biomass, with little improvement in model performance when other plant variables (height, bole wood density), or site characteristics (climate, age, management) were included. Predictions of stand-based biomass from allometric models of varying levels of generalization (species-specific, plant functional type) were validated using whole-plot harvest data from 17 contrasting stands (range: 9-356 Mg ha(-1) ). Losses in efficiency of prediction were plant functional types. Development of new species-specific models is only warranted when gains in accuracy of stand-based predictions are relatively high (e.g. high-value monocultures). PMID:26683241

  6. LINE-ABOVE-GROUND ATTENUATOR

    Wilds, R.B.; Ames, J.R.

    1957-09-24

    The line-above-ground attenuator provides a continuously variable microwave attenuator for a coaxial line that is capable of high attenuation and low insertion loss. The device consists of a short section of the line-above- ground plane type transmission lime, a pair of identical rectangular slabs of lossy material like polytron, whose longitudinal axes are parallel to and indentically spaced away from either side of the line, and a geared mechanism to adjust amd maintain this spaced relationship. This device permits optimum fineness and accuracy of attenuator control which heretofore has been difficult to achieve.

  7. Water Activities in Laxemar Simpevarp. The final disposal facility for spent nuclear fuel - removal of groundwater and water activities above ground; Vattenverksamhet i Laxemar-Simpevarp. Slutfoervarsanlaeggning foer anvaent kaernbraensle - bortledande av grundvatten samt vattenverksamheter ovan mark

    Werner, Kent (EmpTec (Sweden)); Hamren, Ulrika; Collinder, Per (Ekologigruppen AB (Sweden))

    2010-12-15

    This report concerns water operations (Chapter 11 in the Environmental Code) below and above ground associated with construction, operation, and decommissioning of a repository for spent nuclear fuel in Laxemar in the municipality of Oskarshamn. SKB has chosen Forsmark in the municipality of Oesthammar as site for the repository, and the report hence describes a non-chosen alternative. The report provides a comprehensive description of how the water operations would be executed, their hydrogeological and hydrological effects and the resulting consequences. The description is a background material for comparisons between the two sites in terms of water operations. The underground part of a repository in Laxemar would, among other things, consist of an access ramp and a repository area at a depth of approximately 500 metres. The construction, operation, and decommissioning phases would in total comprise a time period of 60-70 years. Inflowing groundwater would be diverted during construction and operation. The modelling tool MIKE SHE has been used to assess the effects of the groundwater diversion, for instance in terms of groundwater levels and stream discharges. According to MIKE SHE calculations for a hypothetical case with a fully open repository, the total groundwater inflow would be in the order of 55-90 litres per second depending on the permeability of the grouted zone around ramp, shafts and tunnels. In reality, the whole repository would not be open simultaneously, and the inflow would therefore be less. The groundwater diversion would cause groundwater- level drawdown in the rock, which in turn would lead to drawdown of the groundwater table in relatively large areas above and around the repository. According to model calculations, there would be an insignificant drawdown of the water level in Lake Frisksjoen, the largest lake in the area. The discharge in the most important stream of the area (Laxemaraan) would be reduced by less than ten percent

  8. Forest Above Ground Biomass Estimation in China

    Zhao, D.; Zeng, Y.; Wu, B.; Li, X.

    2013-12-01

    In order to study the carbon cycling in China deeply, a forest above ground biomass (AGB) estimation research is carried out under the support of 'Strategic Priority Research Program - Climate Change: Carbone Budget and Related Issues' of the Chinese Academy of Sciences (Carbon Project). The research aims to estimate the forest AGB in 2000, 2005 and 2010 in China, and analyzes its dynamic changes. The overall thinking of the research is using field works and airborne LiDAR data as basis to estimate the AGB in GLAS footprints, and then extrapolating discrete AGB to continuous results with optical and auxiliary data. Due to the large area of China, totally 8 sub-areas are marked out based on the different forest ecosystems and some other factors (Table 1 and Fig. 1). Here, a latest China's land cover product (the background of Fig 1), named 'ChinaCover', and also supported by the 'Carbon Project', is imported to classify the forest types. There are around 5000 sample plots (Table 1) surveyed by the 'Carbon Project'. It can provide a large number of training and validation data. At the same time, the research sets 6 other typical sample areas, which have areas of 60 to 200 km2, and airborne LiDAR flights are carried out to obtain high accuracy AGB in these areas. With the sample plots and 6 typical sample areas, the AGB in GLAS footprint is estimated. Since the sample plots and LiDAR flights were carried out in 2012, the height and area parameters extracted from GLAS footprint are corrected by tree growth model of different forest types. In a further step, extrapolation models are built together with time-series MODIS and auxiliary data. These models fully consider the time-series features and propose several long time-series indices to minimize the influence of spectral saturation. Results are validated by samples and compared to the result of some other researches. At last, the models are applied to the data of 2000, 2005 and 2010 to get the corresponding AGB maps

  9. ERC hazard classification matrices for above ground structures and groundwater and soil remediation activities

    This document provides the status of the preliminary hazard classification (PHC) process for the Environmental Restoration Contractor (ERC) above ground structures and groundwater and soil remediation activities currently underway for planned for fiscal year (FY) 1997. This classification process is based on current US Department of Energy (DOE), Richland Operations Office (RL) guidance for the classification of facilities and activities containing radionuclide and nonradiological hazardous material inventories. The above ground structures presented in the matrices were drawn from the Bechtel Hanford, Inc. (BHI) Decontamination and Decommissioning (D and D) Project Facility List (DOE 1996), which identifies the facilities in the RL-Environmental Restoration baseline contract in 1997. This document contains the following two appendices: (1) Appendix A, which consists of a matrix identifying PHC documents that have been issued for BHI's above ground structures and groundwater and soil remediation activities underway or planned for FY 1997, and (2) Appendix B, which consists of a matrix showing anticipated PHCs for above ground structures, and groundwater and soil remediation activities underway or planned for FY 1997. Appendix B also shows the schedule for finalization of PHCs for above ground structures with an anticipated classification of Nuclear

  10. Xenon monitoring and the Comprehensive Nuclear-Test-Ban Treaty

    Bowyer, Theodore W. [Nuclear Explosion Monitoring Program, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States)

    2014-05-09

    How do you monitor (verify) a CTBT? It is a difficult challenge to monitor the entire world for nuclear tests, regardless of size. Nuclear tests 'normally' occur underground, above ground or underwater. Setting aside very small tests (let's limit our thinking to 1 kiloton or more), nuclear tests shake the ground, emit large amounts of radioactivity, and make loud noises if in the atmosphere (or hydroacoustic waves if underwater)

  11. Regional analysis of ground and above-ground climate

    1981-12-01

    The regional suitability of underground construction as a climate control technique is discussed with reference to (1) a bioclimatic analysis of long-term weather data for 29 locations in the United States to determine appropriate above ground climate control techniques, (2) a data base of synthesized ground temperatures for the coterminous United States, and (3) monthly dew point ground temperature comparisons for identifying the relative likelihood of condensation from one region to another. It is concluded that the suitability of earth tempering as a practice and of specific earth-sheltered design stereotypes varies geographically; while the subsurface almost always provides a thermal advantage on its own terms when compared to above ground climatic data, it can, nonetheless, compromise the effectiveness of other, regionally more important climate control techniques. Also contained in the report are reviews of above and below ground climate mapping schemes related to human comfort and architectural design, and detailed description of a theoretical model of ground temperature, heat flow, and heat storage in the ground. Strategies of passive climate control are presented in a discussion of the building bioclimatic analysis procedure which has been applied in a computer analysis of 30 years of weather data for each of 29 locations in the United States.

  12. Regional analysis of ground and above-ground climate

    1981-12-01

    The regional suitability of underground construction as a climate control technique is discussed with reference to (1) a bioclimatic analysis of long term weather data for 29 locations in the United States to determine appropriate above ground climate control techniques, (2) a data base of synthesized ground temperatures for the coterminous United States, and (3) monthly dew point ground temperature comparisons for identifying the relative likelihood of condensation from one region to another. It is concluded that the suitability of Earth tempering as a practice and of specific Earth sheltered design stereotypes varies geographically; while the subsurface almost always provides a thermal advantage on its own terms when compared to above ground climatic data, it can, nonetheless, compromise the effectiveness of other, regionally more important climate control techniques. Reviews of above and below ground climate mapping schemes related to human comfort and architectural design, and detailed description of a theoretical model of ground temperature, heat flow, and heat storage in the ground are included. Strategies of passive climate control are presented in a discussion of the building bioclimatic analysis procedure which has been applied in a computer analysis of 30 years of weather data for each of 20 locations in the United States.

  13. Above-ground biomass functions for Scots pine in Lithuania

    Miksys, Virgilijus; Varnagiryte-Kabasinskiene, Iveta; Armolaitis, Kestutis [Lithuanian Forest Research Institute, Liepu 1, Girionys, LT-53101 Kaunas District (Lithuania); Stupak, Inge [Forest and Landscape Denmark, Hoersholm Kongevej 11, DK-2970 Hoersholm (Denmark); Kukkola, Mikko [The Finnish Forest Research Institute, Vantaa Research Centre, Vantaa Unit, PL 18, 01301 Vantaa (Finland); Wojcik, Josef [Forest Research Institute, Sekocin-Las, 05-090 Raszyn (Poland)

    2007-10-15

    This study presents biomass functions applicable to Scots pine (Pinus sylvestris L.) on Arenosols in Lithuania, and exemplifies the potential biomass removal from Scots pine stands during thinnings. Scots pine is the most common tree species on Arenosols in Lithuania. Stands of ages 10, 20, 40, 50 and 65 years were chosen for the biomass study. We sampled 5 Scots pine trees per plot (in total 25 trees) that were stratified according to the basal area. The sampling was performed in April 2003, before the vegetative period. The following components of each tree were sampled for the above-ground biomass measurements: (1) 5 stem discs, (2) 1 branch with needles from each whorl and (3) 1 dead branch per tree. Observed biomasses of above-ground components were examined using a non-linear regression model, using stem diameter (D), tree height (H) and D{sup 2}H as independent variables. For stemwood biomass, the best approximation was D{sup 2}H. However, D{sup 2}H was not the best parameter for crown biomass because it does not allow evaluation of the opposite effects of diameter and height on crown biomass. The calculations at stand level showed that crown biomass changed insignificantly with the increase in stand age. However, the total stand biomass increased with age due to the growth of the stem. The removal of all logging residues from the Scots pine stand over a 100-year rotation could increase extraction of forest fuel by 15-20% compared with conventional harvesting. (author)

  14. Nuclear stress test

    ... Persantine stress test; Thallium stress test; Stress test - nuclear; Adenosine stress test; Regadenoson stress test; CAD - nuclear stress; Coronary artery disease - nuclear stress; Angina - nuclear ...

  15. Diversity, Population Structure, and Above Ground Biomass in Woody Species on Ngomakurira Mountain, Domboshawa, Zimbabwe

    Clemence Zimudzi

    2016-01-01

    Full Text Available The diversity, structure, species composition, and above ground biomass of woody plants on Ngomakurira mountain in Zimbabwe were studied. A systematic random sampling approach was adopted to establish 52 sampling plots measuring 10 × 10 m across 3 study strata in the 1266 ha study area. Woody species occurring in each plot were identified and the circumferences of trees with diameters >8.0 cm at 1.3 m height were measured. A total of 91 species belonging to 74 genera and 39 families were identified in the sample plots. A Shannon-Wiener index mean value of 3.12 was obtained indicating high species diversity on the mountain. The DBH size class distribution showed inverse J distribution patterns across the three study strata, but with only 3 individual plants with DBH > 30 cm. Mean basal area was 15.21 m2 ha−1 with U. kirkiana and J. globiflora contributing approximately 30% of the basal area. The estimated above ground biomass ranged from 34.5 to 65.1 t ha−1. Kruskal-Wallis-H test showed no significant differences in species richness, stem density, basal area, above ground biomass, and evenness, across the study strata (p<0.05. Ngomakurira woodland has potential to regenerate due to the presence of many stems in the small diameter size classes.

  16. Cathodic protection for the bottoms of above ground storage tanks

    Mohr, John P. [Tyco Adhesives, Norwood, MA (United States)

    2004-07-01

    Impressed Current Cathodic Protection has been used for many years to protect the external bottoms of above ground storage tanks. The use of a vertical deep ground bed often treated several bare steel tank bottoms by broadcasting current over a wide area. Environmental concerns and, in some countries, government regulations, have introduced the use of dielectric secondary containment liners. The dielectric liner does not allow the protective cathodic protection current to pass and causes corrosion to continue on the newly placed tank bottom. In existing tank bottoms where inadequate protection has been provided, leaks can develop. In one method of remediation, an old bottom is covered with sand and a double bottom is welded above the leaking bottom. The new bottom is welded very close to the old bottom, thus shielding the traditional cathodic protection from protecting the new bottom. These double bottoms often employ the use of dielectric liner as well. Both the liner and the double bottom often minimize the distance from the external tank bottom. The minimized space between the liner, or double bottom, and the bottom to be protected places a challenge in providing current distribution in cathodic protection systems. This study examines the practical concerns for application of impressed current cathodic protection and the types of anode materials used in these specific applications. One unique approach for an economical treatment using a conductive polymer cathodic protection method is presented. (author)

  17. Can above-ground ecosystem services compensate for reduced fertilizer input and soil organic matter in annual crops?

    van Gils, Stijn; van der Putten, Wim H; Kleijn, David

    2016-01-01

    1.Above-ground and below-ground environmental conditions influence crop yield by pollination, pest pressure, and resource supply. However, little is known about how interactions between these factors contribute to yield. Here, we used oilseed rape Brassica napus to test their effects on crop yield.2

  18. Deep Neural Networks for Above-Ground Detection in Very High Spatial Resolution Digital Elevation Models

    Marmanis, D.; Adam, F.; Datcu, M.; Esch, T.; Stilla, U.

    2015-03-01

    Deep Learning techniques have lately received increased attention for achieving state-of-the-art results in many classification problems, including various vision tasks. In this work, we implement a Deep Learning technique for classifying above-ground objects within urban environments by using a Multilayer Perceptron model and VHSR DEM data. In this context, we propose a novel method called M-ramp which significantly improves the classifier's estimations by neglecting artefacts, minimizing convergence time and improving overall accuracy. We support the importance of using the M-ramp model in DEM classification by conducting a set of experiments with both quantitative and qualitative results. Precisely, we initially train our algorithm with random DEM tiles and their respective point-labels, considering less than 0.1% over the test area, depicting the city center of Munich (25 km2). Furthermore with no additional training, we classify two much larger unseen extents of the greater Munich area (424 km2) and Dongying city, China (257 km2) and evaluate their respective results for proving knowledge-transferability. Through the use of M-ramp, we were able to accelerate the convergence by a magnitude of 8 and achieve a decrease in above-ground relative error by 24.8% and 5.5% over the different datasets.

  19. Estimating Stand Volume and Above-Ground Biomass of Urban Forests Using LiDAR

    Vincenzo Giannico

    2016-04-01

    Full Text Available Assessing forest stand conditions in urban and peri-urban areas is essential to support ecosystem service planning and management, as most of the ecosystem services provided are a consequence of forest stand characteristics. However, collecting data for assessing forest stand conditions is time consuming and labor intensive. A plausible approach for addressing this issue is to establish a relationship between in situ measurements of stand characteristics and data from airborne laser scanning (LiDAR. In this study we assessed forest stand volume and above-ground biomass (AGB in a broadleaved urban forest, using a combination of LiDAR-derived metrics, which takes the form of a forest allometric model. We tested various methods for extracting proxies of basal area (BA and mean stand height (H from the LiDAR point-cloud distribution and evaluated the performance of different models in estimating forest stand volume and AGB. The best predictors for both models were the scale parameters of the Weibull distribution of all returns (except the first (proxy of BA and the 95th percentile of the distribution of all first returns (proxy of H. The R2 were 0.81 (p < 0.01 for the stand volume model and 0.77 (p < 0.01 for the AGB model with a RMSE of 23.66 m3·ha−1 (23.3% and 19.59 Mg·ha−1 (23.9%, respectively. We found that a combination of two LiDAR-derived variables (i.e., proxy of BA and proxy of H, which take the form of a forest allometric model, can be used to estimate stand volume and above-ground biomass in broadleaved urban forest areas. Our results can be compared to other studies conducted using LiDAR in broadleaved forests with similar methods.

  20. Estimating Above-Ground Carbon Biomass in a Newly Restored Coastal Plain Wetland Using Remote Sensing

    Riegel, Joseph B.; Emily Bernhardt; Jennifer Swenson

    2013-01-01

    Developing accurate but inexpensive methods for estimating above-ground carbon biomass is an important technical challenge that must be overcome before a carbon offset market can be successfully implemented in the United States. Previous studies have shown that LiDAR (light detection and ranging) is well-suited for modeling above-ground biomass in mature forests; however, there has been little previous research on the ability of LiDAR to model above-ground biomass in areas with young, aggradi...

  1. EnviroAtlas - Above Ground Live Biomass Carbon Storage for the Conterminous United States- Forested

    U.S. Environmental Protection Agency — This EnviroAtlas dataset includes the average above ground live dry biomass estimate for the Watershed Boundary Dataset (WBD) 12-digit Hydrologic Unit (HUC) in kg/m...

  2. Interactions of ectomycorrhizas and above-ground insect herbivores on silver birch

    Nerg, Anne-Marja; Kasurinen, Anne; Holopainen, Toini; Julkunen-Tiitto, Riitta; Neuvonen, Seppo; Holopainen, Jarmo K.

    2009-01-01

    Mycorrhizas are mostly beneficial to host plant growth and survival, e.g., due to improved water and nutrient uptake and enhanced pathogen protection, but also a significant amount of host plant carbon is allocated below-ground to support the mycorrhizal growth. These facts and on the other hand the possibility of mycorrhizas to mediate changes in above-ground defensive chemistry may affect performance of above-ground insect herbivores with different feeding guilds. To see the functionality o...

  3. Below-ground herbivory limits induction of extrafloral nectar by above-ground herbivores

    Huang, Wei; Siemann, Evan; Carrillo, Juli; Ding, Jianqing

    2015-01-01

    Background and Aims Many plants produce extrafloral nectar (EFN), and increase production following above-ground herbivory, presumably to attract natural enemies of the herbivores. Below-ground herbivores, alone or in combination with those above ground, may also alter EFN production depending on the specificity of this defence response and the interactions among herbivores mediated through plant defences. To date, however, a lack of manipulative experiments investigating EFN production induc...

  4. Root absorption of 222Rn and its transfer into above-ground plant organs

    Experimental data are given on the content of genetically related pairs of radionuclides (226Ra and 222Rn; 224Ra and 220Rn) in soils and the above-ground phytomass of plants growing on plots with differing genesis of the higher concentrations of natural radionuclides in soils. Methods for determining gaseous radionuclides in the above-ground phytomass are described. Different transport routes of 222Rn and 220Rn into above-ground plant organs are considered. The noted absence of balance between 222Rn and 226Ra in plants as well as higher 222Rn/226Ra ratios in the above-ground phytomass as compared to that of the root-containing soil layer (25- to 185-fold) appears to be accounted for by the root pathway of 222Rn uptake and transport of this radionuclide to above-ground plants organs. The existence of the root pathway for 222Rn uptake is proved by direct observations of daily radionuclide movement with bleeding sap in experiments on pumpkins. For the short-lived Rn isotopes, 220Rn and 218Rn, the root pathway of uptake and transport to the above-ground phytomass is less probable, and this causes a notable redistribution of gaseous radionuclides during their movement along the soil-plant route

  5. Final Harvest of Above-Ground Biomass and Allometric Analysis of the Aspen FACE Experiment

    Mark E. Kubiske

    2013-04-15

    The Aspen FACE experiment, located at the US Forest Service Harshaw Research Facility in Oneida County, Wisconsin, exposes the intact canopies of model trembling aspen forests to increased concentrations of atmospheric CO2 and O3. The first full year of treatments was 1998 and final year of elevated CO2 and O3 treatments is scheduled for 2009. This proposal is to conduct an intensive, analytical harvest of the above-ground parts of 24 trees from each of the 12, 30 m diameter treatment plots (total of 288 trees) during June, July & August 2009. This above-ground harvest will be carefully coordinated with the below-ground harvest proposed by D.F. Karnosky et al. (2008 proposal to DOE). We propose to dissect harvested trees according to annual height growth increment and organ (main stem, branch orders, and leaves) for calculation of above-ground biomass production and allometric comparisons among aspen clones, species, and treatments. Additionally, we will collect fine root samples for DNA fingerprinting to quantify biomass production of individual aspen clones. This work will produce a thorough characterization of above-ground tree and stand growth and allocation above ground, and, in conjunction with the below ground harvest, total tree and stand biomass production, allocation, and allometry.

  6. Nondestructive estimates of above-ground biomass using terrestrial laser scanning

    Calders, K.; Newnham, G.; Burt, A.; Murphy, S.; Raumonen, P.; Herold, M.; Culvenor, D.; Avitabile, V.; Disney, M.; Armston, J.; Kaasalainen, M.

    2015-01-01

    Allometric equations are currently used to estimate above-ground biomass (AGB) based on the indirect relationship with tree parameters. Terrestrial laser scanning (TLS) can measure the canopy structure in 3D with high detail. In this study, we develop an approach to estimate AGB from TLS data, which

  7. Grass allometry and estimation of above-ground biomass in tropical alpine tussock grasslands

    Oliveras Menor, I.; Eynden, van der M.; Malhi, Y.; Cahuana, N.; Menor, C.; Zamora, F.; Haugaasen, T.

    2014-01-01

    The puna/páramo grasslands span across the highest altitudes of the tropical Andes, and their ecosystem dynamics are still poorly understood. In this study we examined the above-ground biomass and developed species specific and multispecies power-law allometric equations for four tussock grass speci

  8. Estimating above-ground carbon biomass in a newly restored coastal plain wetland using remote sensing.

    Joseph B Riegel

    Full Text Available Developing accurate but inexpensive methods for estimating above-ground carbon biomass is an important technical challenge that must be overcome before a carbon offset market can be successfully implemented in the United States. Previous studies have shown that LiDAR (light detection and ranging is well-suited for modeling above-ground biomass in mature forests; however, there has been little previous research on the ability of LiDAR to model above-ground biomass in areas with young, aggrading vegetation. This study compared the abilities of discrete-return LiDAR and high resolution optical imagery to model above-ground carbon biomass at a young restored forested wetland site in eastern North Carolina. We found that the optical imagery model explained more of the observed variation in carbon biomass than the LiDAR model (adj-R(2 values of 0.34 and 0.18 respectively; root mean squared errors of 0.14 Mg C/ha and 0.17 Mg C/ha respectively. Optical imagery was also better able to predict high and low biomass extremes than the LiDAR model. Combining both the optical and LiDAR improved upon the optical model but only marginally (adj-R(2 of 0.37. These results suggest that the ability of discrete-return LiDAR to model above-ground biomass may be rather limited in areas with young, small trees and that high spatial resolution optical imagery may be the better tool in such areas.

  9. Impact of Ground-Applied Termiticides on the Above-Ground Foraging Behavior of the Formosan Subterranean Termite.

    Henderson, Gregg; Gautam, Bal K; Wang, Cai

    2016-01-01

    We conducted a laboratory study to determine the impact of ground-applied termiticides on the above-ground foraging behavior of Coptotermes formosanus. Two concentrations (1 and 10 ppm) each of three termiticides, viz. fipronil, imidacloprid and chlorantraniliprole, were tested. After one month post-treatment (fipronil 10 ppm was run for 12 days only and all other treatments were run for one month), fipronil had the lowest percentage of survival (3%-4%) at both concentrations. Termite survival ranged from 31% to 40% in the case of imidacloprid treatments and 10 ppm chlorantraniliprole. However, 1 ppm chlorantraniliprole did not cause significant mortality compared to the controls. Foraging on the bottom substrate was evident in all replicates for all chemicals initially. However, a portion of the foraging population avoided the ground treatment toxicants after several days of bottom foraging. Only the slower-acting non-repellents created this repellent barrier, causing avoidance behavior that was most likely due to dead termites and fungus buildup on the treated bottom substrate. Fipronil appeared more toxic and faster acting at the concentrations tested, thus limiting this repellent effect. Suggestions by the pest control industry in Louisiana that some non-repellents can create a repellent barrier stranding live termites above ground are supported by this laboratory study. PMID:27571108

  10. Pendugaan Cadangan Karbon Above Ground Biomass pada Ruang Terbuka Hijau di Kota Medan

    Sitorus, Novita Ariani

    2015-01-01

    NOVITA ARIANI SITORUS : The Estimate of Carbon Stocks Above Ground Biomass at Green Open Space in Medan City. Under the supervision of RAHMAWATY and ABDUL RAUF. Global warming is the main environmental problems of this millennium. Carbon dioxide (CO2) is the main cause for global warming. Green open space such as urban forest and urban park play a role in mitigating global warming in urban areas because the vegetation that is capable to absorb CO2 from the atmosphere through photosynthes...

  11. Landsat Imagery-Based Above Ground Biomass Estimation and Change Investigation Related to Human Activities

    Chaofan Wu; Huanhuan Shen; Ke Wang; Aihua Shen; Jinsong Deng; Muye Gan

    2016-01-01

    Forest biomass is a significant indicator for substance accumulation and forest succession, and a spatiotemporal biomass map would provide valuable information for forest management and scientific planning. In this study, Landsat imagery and field data cooperated with a random forest regression approach were used to estimate spatiotemporal Above Ground Biomass (AGB) in Fuyang County, Zhejiang Province of East China. As a result, the AGB retrieval showed an increasing trend for the past decade...

  12. Disposal facility in olkiluoto, description of above ground facilities in lift transport alternative

    The above ground facilities of the disposal plant on the Olkiluoto site are described in this report as they will be when the operation of the disposal facility starts in the year 2020. The disposal plant is visualised on the Olkiluoto site. Parallel construction of the deposition tunnels and disposal of the spent fuel canisters constitute the principal design basis of the disposal plant. The annual production of disposal canisters for spent fuel amounts to about 40. Production of 100 disposal canisters has been used as the capacity basis. Fuel from the Olkiluoto plant and from the Loviisa plant will be encapsulated in the same production line. The disposal plant will require an area of about 15 to 20 hectares above ground level. The total building volume of the above ground facilities is about 75000 m3. The purpose of the report is to provide the base for detailed design of the encapsulation plant and the repository spaces, as well as for coordination between the disposal plant and ONKALO. The dimensioning bases for the disposal plant are shown in the Tables at the end of the report. The report can also be used as a basis for comparison in deciding whether the fuel canisters are transported to the repository by a lift or by a vehicle along the access tunnel. (orig.)

  13. Above Ground Biomass-carbon Partitioning, Storage and Sequestration in a Rehabilitated Forest, Bintulu, Sarawak, Malaysia

    Forest degradation and deforestation are some of the major global concerns as it can reduce forest carbon storage and sequestration capacity. Forest rehabilitation on degraded forest areas has the potential to improve carbon stock, hence mitigate greenhouse gases emission. However, the carbon storage and sequestration potential in a rehabilitated tropical forest remains unclear due to the lack of information. This paper reports an initiative to estimate biomass-carbon partitioning, storage and sequestration in a rehabilitated forest. The study site was at the UPM-Mitsubishi Corporation Forest Rehabilitation Project, UPM Bintulu Sarawak Campus, Bintulu, Sarawak. A plot of 20 x 20 m2 was established each in site 1991 (Plot 1991), 1999 (Plot 1999) and 2008 (Plot 2008). An adjacent natural regenerating secondary forest plot (Plot NF) was also established for comparison purposes. The results showed that the contribution of tree component biomass/ carbon to total biomass/ carbon was in the order of main stem > branch > leaf. As most of the trees were concentrated in diameter size class = 10 cm for younger rehabilitated forests, the total above ground biomass/ carbon was from this class. These observations suggest that the forests are in the early successional stage. The total above ground biomass obtained for the rehabilitated forest ranged from 4.3 to 4,192.3 kg compared to natural regenerating secondary forest of 3,942.3 kg while total above ground carbon ranged from 1.9 to 1,927.9 kg and 1,820.4 kg, respectively. The mean total above ground biomass accumulated ranged from 1.3 x 10-2 to 20.5 kg/ 0.04 ha and mean total carbon storage ranged from 5.9 x 10-3 to 9.4 kg/ 0.04 ha. The total CO2 sequestrated in rehabilitated forest ranged from 6.9 to 7,069.1 kg CO2/ 0.04 ha. After 19 years, the rehabilitated forest had total above ground biomass and carbon storage comparable to the natural regeneration secondary forest. The forest rehabilitated activities have the potential

  14. Above-ground biomass investments and light interception of tropical forest trees and lianas early in succession

    Selaya, N.G.; Anten, N.P.R.; Oomen, R.J.; Matthies, M.; Werger, M.J.A.

    2007-01-01

    Background and Aims Crown structure and above-ground biomass investment was studied in relation to light interception of trees and lianas growing in a 6-month-old regenerating forest. Methods The vertical distribution of total above-ground biomass, height, diameter, stem density, leaf angles and cro

  15. Forest soil respiration rate and delta13C is regulated by recent above ground weather conditions.

    Ekblad, Alf; Boström, Björn; Holm, Anders; Comstedt, Daniel

    2005-03-01

    Soil respiration, a key component of the global carbon cycle, is a major source of uncertainty when estimating terrestrial carbon budgets at ecosystem and higher levels. Rates of soil and root respiration are assumed to be dependent on soil temperature and soil moisture yet these factors often barely explain half the seasonal variation in soil respiration. We here found that soil moisture (range 16.5-27.6% of dry weight) and soil temperature (range 8-17.5 degrees C) together explained 55% of the variance (cross-validated explained variance; Q2) in soil respiration rate (range 1.0-3.4 micromol C m(-2) s(-1)) in a Norway spruce (Picea abies) forest. We hypothesised that this was due to that the two components of soil respiration, root respiration and decomposition, are governed by different factors. We therefore applied PLS (partial least squares regression) multivariate modelling in which we, together with below ground temperature and soil moisture, used the recent above ground air temperature and air humidity (vapour pressure deficit, VPD) conditions as x-variables. We found that air temperature and VPD data collected 1-4 days before respiration measurements explained 86% of the seasonal variation in the rate of soil respiration. The addition of soil moisture and soil temperature to the PLS-models increased the Q2 to 93%. delta13C analysis of soil respiration supported the hypotheses that there was a fast flux of photosynthates to root respiration and a dependence on recent above ground weather conditions. Taken together, our results suggest that shoot activities the preceding 1-6 days influence, to a large degree, the rate of root and soil respiration. We propose this above ground influence on soil respiration to be proportionally largest in the middle of the growing season and in situations when there is large day-to-day shifts in the above ground weather conditions. During such conditions soil temperature may not exert the major control on root respiration. PMID

  16. Applications of above-ground gas stores. Demand-oriented supply; Einsatzmoeglichkeiten von Obertagespeichern. Kundenorientierte Bedarfsdeckung

    Deschkan, Peter [Wien Energie Speicher GmbH, Wien (Austria)

    2010-07-01

    From the view of municipal utilities in Austria, the applications and uses of above-ground gas stores have changed considerably during the past few years as a result of the deregulation of the natural gas markets. While it used to be normal to consider spherical or tubular natural gas reservoirs as part of the gas grid, new legal and commercial aspects have since then come to the fore and must be taken into account if these niche products of the natural gas store market are to be used successfully. (orig.)

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

    Johnson, Michelle; Galbraith, David; Gloor, Manuel; De Deaurwaerder, Hannes; Guimberteau, Mattieu; Rammig, Anja; Thonicke, Kristin; Verbeeck, Hans; von Randow, Celso; Monteagudo Mendoza, Abel; Phillips, Oliver L; Brienen, Roel; Feldpausch, Ted R.; Lopez Gonzales, Gabriela; Fauset, Sophie

    2016-01-01

    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 biom...

  18. Frequencies of Dicentric Chromosome and Translocation in Lymphocytes from Residents in Radio-contaminated Villages near Semipalatinsk Nuclear Explosion Test Site

    Tanaka, Kimio; Iida, Shozho; Takeichi, Nobuo; Hoshi, Masaharu

    2012-01-01

    More than 400 above-ground and underground nuclear explosion tests were conducted at Semipalatinsk nuclear explosion test site (SNETS). The significant radioactive substances was released and radioactive plumes moved on villages at the time of explosion test, then residents in villages near SNETS are considered to be exposed internally and externally. In order to assess the biological effects on residents, frequencies of chromosome aberrations in peripheral blood lymphocytes were observed in ...

  19. A first map of tropical Africa's above-ground biomass derived from satellite imagery

    Observations from the moderate resolution imaging spectroradiometer (MODIS) were used in combination with a large data set of field measurements to map woody above-ground biomass (AGB) across tropical Africa. We generated a best-quality cloud-free mosaic of MODIS satellite reflectance observations for the period 2000-2003 and used a regression tree model to predict AGB at 1 km resolution. Results based on a cross-validation approach show that the model explained 82% of the variance in AGB, with a root mean square error of 50.5 Mg ha-1 for a range of biomass between 0 and 454 Mg ha-1. Analysis of lidar metrics from the Geoscience Laser Altimetry System (GLAS), which are sensitive to vegetation structure, indicate that the model successfully captured the regional distribution of AGB. The results showed a strong positive correlation (R2 = 0.90) between the GLAS height metrics and predicted AGB.

  20. Decades of nuclear testing

    The United States carried out the world's first nuclear test in 1945. The test marked the beginning of an arms race between the great powers that lasted for decades. Innumerable nuclear test explosions were detonated to test and refine the weapons. The arms race picked up speed in the 1950s and culminated in 1958, when the United States detonated 77 and the Soviet Union 35 nuclear explosions. This was followed by the first pause in nuclear testing, brought about through the efforts of the Pugwash organisation consisting of the world's foremost scientists. Finland, too, received its share of the radioactive fallout coming from atmospheric nuclear explosions. Rain water samples have been studied for radioactivity in Finland since the mid-1950s. The first studies to determine the internal radiation doses caused by radioactive substances in man were conducted in the late 1950s by measuring cesium and strontium contents in grass and in milk. The efficiency of research and radiation monitoring improved in the 1960s, which was also a time when training in the sector developed rapidly. In consequence, when the accident in Chernobyl took place Finland had already gained valuable experience needed for rapid determination of unexpected fallout. (orig.) (3 figs.)

  1. Nuclear test ban verification

    This report describes verification and its rationale, the basic tasks of seismic verification, the physical basis for earthquake/explosion source discrimination and explosion yield determination, the technical problems pertaining to seismic monitoring of underground nuclear tests, the basic problem-solving strategy deployed by the forensic seismology resarch team at the University of Toronto, and the scientific significance of the team's research. The research carried out at the Univeristy of Toronto has two components: teleseismic verification using P wave recordings from the Yellowknife Seismic Array (YKA), and regional (close-in) verification using high-frequency Lg and Pn recordings from the Eastern Canada Telemetered Network. Major differences have been found in P was attenuation among the propagation paths connecting the YKA listening post with seven active nuclear explosion testing areas in the world. Significant revisions have been made to previously published P wave attenuation results, leading to more interpretable nuclear explosion source functions. (11 refs., 12 figs.)

  2. Above ground standing biomass and carbon storage in village bamboos in North East India

    Jyoti Nath, Arun; Das, Ashesh Kumar [Department of Ecology and Environmental Science, Assam University, Silchar 788011, Assam (India); Das, Gitasree [Department of Statistics, North Eastern Hill University, Shillong 793022, Meghalaya (India)

    2009-09-15

    Bamboo forms an important component in the traditional landscape of North East India. For biomass estimation of village bamboos of Barak Valley, North East India, allometric relationships were developed by harvest method describing leaf, branch and culm biomass with DBH as an independent variable using a log linear model. The culm density of the stand was 8950 culms ha{sup -1} during 2005 of which 67% of growing stock was represented by Bambusa cacharensis, 17.88% by Bambusa vulgaris and 15.12% by Bambusa balcooa. Above ground stand biomass was 121.51 t ha{sup -1} of which 86% was contributed by culm component followed by branch (10%) and leaf (4%). With respect to species, B. cacharensis made up to 46% of total stand biomass followed by B. vulgaris (28%) and B. balcooa (26%). Carbon storage in the above ground biomass was 61.05 t ha{sup -1}. Allocation of C was more in culm components (53.05 t ha{sup -1}) than in branch (5.81 t ha{sup -1}) and leaf (2.19 t ha{sup -1}). Carbon storage in the litter floor mass was 2.40 t ha{sup -1}, of which leaf litter made up the highest amount (1.37 t ha{sup -1}) followed by sheath (0.86 t ha{sup -1}) and branch (0.17 t ha{sup -1}). Carbon stock in the soil up to 30 cm depth was 57.3 t ha{sup -1}. Gross C stock in the plantation was estimated to be 120.75 t ha{sup -1}. Carbon storage estimated in the bamboo stand of present study offers insights into the opportunity of village bamboos in the rural landscape for carbon storage through carbon sequestration. Management and utilization of village bamboos as a potential source of carbon sink by smallholder farmers are discussed in the context of their livelihood security and the Millennium Development Goals of the United Nations. (author)

  3. A terrestrial biosphere model optimized to atmospheric CO2 concentration and above ground woody biomass

    Saito, M.; Ito, A.; Maksyutov, S. S.

    2013-12-01

    This study documents an optimization of a prognostic biosphere model (VISIT; Vegetation Integrative Similator for Trace gases) to observations of atmospheric CO2 concentration and above ground woody biomass by using a Bayesian inversion method combined with an atmospheric tracer transport model (NIES-TM; National Institute for Environmental Studies / Frontier Research Center for Global Change (NIES/FRCGC) off-line global atmospheric tracer transport model). The assimilated observations include 74 station records of surface atmospheric CO2 concentration and aggregated grid data sets of above ground woody biomass (AGB) and net primary productivity (NPP) over the globe. Both the biosphere model and the atmospheric transport model are used at a horizontal resolution of 2.5 deg x 2.5 deg grid with temporal resolutions of a day and an hour, respectively. The atmospheric transport model simulates atmospheric CO2 concentration with nine vertical levels using daily net ecosystem CO2 exchange rate (NEE) from the biosphere model, oceanic CO2 flux, and fossil fuel emission inventory. The models are driven by meteorological data from JRA-25 (Japanese 25-year ReAnalysis) and JCDAS (JMA Climate Data Assimilation System). Statistically optimum physiological parameters in the biosphere model are found by iterative minimization of the corresponding Bayesian cost function. We select thirteen physiological parameter with high sensitivity to NEE, NPP, and AGB for the minimization. Given the optimized physiological parameters, the model shows error reductions in seasonal variation of the CO2 concentrations especially in the northern hemisphere due to abundant observation stations, while errors remain at a few stations that are located in coastal coastal area and stations in the southern hemisphere. The model also produces moderate estimates of the mean magnitudes and probability distributions in AGB and NPP for each biome. However, the model fails in the simulation of the terrestrial

  4. Radioactive contamination of Semipalatinsk test site territory due to atmospheric nuclear test

    It was found that the local fallout of radioactive plumes after above-ground and air tests was the major factor constructing to the radiation situation at the STS territory. Study results confirm the presence of local contaminated areas within STS territory, so called radioactive spots, which alternate with relatively clean area. The radionuclide contamination of areas surrounding epicenters of above-ground explosions have been studied in detail. (author)

  5. Landsat Imagery-Based Above Ground Biomass Estimation and Change Investigation Related to Human Activities

    Chaofan Wu

    2016-02-01

    Full Text Available Forest biomass is a significant indicator for substance accumulation and forest succession, and a spatiotemporal biomass map would provide valuable information for forest management and scientific planning. In this study, Landsat imagery and field data cooperated with a random forest regression approach were used to estimate spatiotemporal Above Ground Biomass (AGB in Fuyang County, Zhejiang Province of East China. As a result, the AGB retrieval showed an increasing trend for the past decade, from 74.24 ton/ha in 2004 to 99.63 ton/ha in 2013. Topography and forest management were investigated to find their relationships with the spatial distribution change of biomass. In general, the simulated AGB increases with higher elevation, especially in the range of 80–200 m, wherein AGB acquires the highest increase rate. Moreover, the forest policy of ecological forest has a positive effect on the AGB increase, particularly within the national level ecological forest. The result in this study demonstrates that human activities have a great impact on biomass distribution and change tendency. Furthermore, Landsat image-based biomass estimates would provide illuminating information for forest policy-making and sustainable development.

  6. Water activities in Forsmark (Part II). The final disposal facility for spent fuel: water activities above ground; Vattenverksamhet i Forsmark (del II). Slutfoervarsanlaeggningen foer anvaent kaernbraensle: Vattenverksamheter ovan mark

    Werner, Kent (EmpTec (Sweden)); Hamren, Ulrika; Collinder, Per (Ekologigruppen AB (Sweden)); Ridderstolpe, Peter (WRS Uppsala AB (Sweden))

    2010-09-15

    The construction of the repository for spent nuclear fuel in Forsmark is associated with a number of measures above ground that constitute water operations according to Chapter 11 in the Swedish Environmental Code. This report, which is an appendix to the Environmental Impact Assessment, describes these water operations, their effects and consequences, and planned measures

  7. Above-ground biomass models for Seabuckthorn (Hippophae salicifolia) in Mustang District, Nepal

    Rajchal, Rajesh; Meilby, Henrik

    2013-01-01

    fresh weight of fruit and oven-dry weight of wood (stem and branches) and leaves were measured and used as a basis for developing biomass models. Diameters of the trees were measured at 30 cm above ground whereas the heights were measured in terms of the total tree height (m). Among several models...... tested, the models suggested for local use were: ln(woody biomass, oven-dry, kg) = -3.083 + 2.436 ln(diameter, cm), ln (fruit biomass, fresh, kg) = -3.237 + 1.346 ln(diameter, cm) and ln(leaf biomass, oven-dry, kg) = -4.013 + 1.403 ln(Diameter, cm) with adjusted coefficients of determination of 0.99, 0.......73 and 0.91 for wood, fruit, and leaves, respectively. The models suggested for a slightly broader range of environmental conditions were: ln (woody biomass, oven-dry, kg) = -3.277 + 0.924 ln(diameter2 × height), ln(Fruit biomass, fresh, kg) = -3.146 + 0.485 ln(diameter2 × height) and ln(leaf biomass...

  8. Facilitation and inhibition: changes in plant nitrogen and secondary metabolites mediate interactions between above-ground and below-ground herbivores

    Huang, Wei; Siemann, Evan; Yang, Xuefang; Wheeler, Gregory S.; Ding, Jianqing

    2013-01-01

    To date, it remains unclear how herbivore-induced changes in plant primary and secondary metabolites impact above-ground and below-ground herbivore interactions. Here, we report effects of above-ground (adult) and below-ground (larval) feeding by Bikasha collaris on nitrogen and secondary chemicals in shoots and roots of Triadica sebifera to explain reciprocal above-ground and below-ground insect interactions. Plants increased root tannins with below-ground herbivory, but above-ground herbivo...

  9. Modelling Growth and Partitioning of Annual Above-Ground Vegetative and Reproductive Biomass of Grapevine

    Meggio, Franco; Vendrame, Nadia; Maniero, Giovanni; Pitacco, Andrea

    2014-05-01

    In the current climate change scenarios, both agriculture and forestry inherently may act as carbon sinks and consequently can play a key role in limiting global warming. An urgent need exists to understand which land uses and land resource types have the greatest potential to mitigate greenhouse gas (GHG) emissions contributing to global change. A common believe is that agricultural fields cannot be net carbon sinks due to many technical inputs and repeated disturbances of upper soil layers that all contribute to a substantial loss both of the old and newly-synthesized organic matter. Perennial tree crops (vineyards and orchards), however, can behave differently: they grow a permanent woody structure, stand undisturbed in the same field for decades, originate a woody pruning debris, and are often grass-covered. In this context, reliable methods for quantifying and modelling emissions and carbon sequestration are required. Carbon stock changes are calculated by multiplying the difference in oven dry weight of biomass increments and losses with the appropriate carbon fraction. These data are relatively scant, and more information is needed on vineyard management practices and how they impact vineyard C sequestration and GHG emissions in order to generate an accurate vineyard GHG footprint. During the last decades, research efforts have been made for estimating the vineyard carbon budget and its allocation pattern since it is crucial to better understand how grapevines control the distribution of acquired resources in response to variation in environmental growth conditions and agronomic practices. The objective of the present study was to model and compare the dynamics of current year's above-ground biomass among four grapevine varieties. Trials were carried out over three growing seasons in field conditions. The non-linear extra-sums-of-squares method demonstrated to be a feasible way of growth models comparison to statistically assess significant differences among

  10. Detection of large above ground biomass variability in lowland forest ecosystems by airborne LiDAR

    J. Jubanski

    2012-08-01

    Full Text Available Quantification of tropical forest Above Ground Biomass (AGB over large areas as input for Reduced Emissions from Deforestation and forest Degradation (REDD+ projects and climate change models is challenging. This is the first study which attempts to estimate AGB and its variability across large areas of tropical lowland forests in Central Kalimantan (Indonesia through correlating airborne Light Detection and Ranging (LiDAR to forest inventory data. Two LiDAR height metrics were analysed and regression models could be improved through the use of LiDAR point densities as input (R2 = 0.88; n = 52. Surveying with a LiDAR point density per square meter of 2–4 resulted in the best cost-benefit ratio. We estimated AGB for 600 km of LiDAR tracks and showed that there exists a considerable variability of up to 140% within the same forest type due to varying environmental conditions. Impact from logging operations and the associated AGB losses dating back more than 10 yr could be assessed by LiDAR but not by multispectral satellite imagery. Comparison with a Landsat classification for a 1 million ha study area where AGB values were based on site specific field inventory data, regional literature estimates, and default values by the Intergovernmental Panel on Climate Change (IPCC showed an overestimation of 46%, 102%, and 137%, respectively. The results show that AGB overestimation may lead to wrong GHG emission estimates due to deforestation in climate models. For REDD+ projects this leads to inaccurate carbon stock estimates and consequently to significantly wrong REDD+ based compensation payments.

  11. Investigating Appropriate Sampling Design for Estimating Above-Ground Biomass in Bruneian Lowland Mixed Dipterocarp Forest

    Lee, S.; Lee, D.; Abu Salim, K.; Yun, H. M.; Han, S.; Lee, W. K.; Davies, S. J.; Son, Y.

    2014-12-01

    Mixed tropical forest structure is highly heterogeneous unlike plantation or mixed temperate forest structure, and therefore, different sampling approaches are required. However, the appropriate sampling design for estimating the above-ground biomass (AGB) in Bruneian lowland mixed dipterocarp forest (MDF) has not yet been fully clarified. The aim of this study was to provide supportive information in sampling design for Bruneian forest carbon inventory. The study site was located at Kuala Belalong lowland MDF, which is part of the Ulu Tembulong National Park, Brunei Darussalam. Six 60 m × 60 m quadrats were established, separated by a distance of approximately 100 m and each was subdivided into quadrats of 10 m × 10 m, at an elevation between 200 and 300 m above sea level. At each plot all free-standing trees with diameter at breast height (dbh) ≥ 1 cm were measured. The AGB for all trees with dbh ≥ 10 cm was estimated by allometric models. In order to analyze changes in the diameter-dependent parameters used for estimating the AGB, different quadrat areas, ranging from 10 m × 10 m to 60 m × 60 m, were used across the study area, starting at the South-West end and moving towards the North-East end. The derived result was as follows: (a) Big trees (dbh ≥ 70 cm) with sparse distribution have remarkable contribution to the total AGB in Bruneian lowland MDF, and therefore, special consideration is required when estimating the AGB of big trees. Stem number of trees with dbh ≥ 70 cm comprised only 2.7% of all trees with dbh ≥ 10 cm, but 38.5% of the total AGB. (b) For estimating the AGB of big trees at the given acceptable limit of precision (p), it is more efficient to use large quadrats than to use small quadrats, because the total sampling area decreases with the former. Our result showed that 239 20 m × 20 m quadrats (9.6 ha in total) were required, while 15 60 m × 60 m quadrats (5.4 ha in total) were required when estimating the AGB of the trees

  12. Effect of nitrogen addition and drought on above-ground biomass of expanding tall grasses Calamagrostis epigejos and Arrhenatherum elatius

    Fiala, Karel; Tůma, Ivan; Holub, Petr

    2011-01-01

    Roč. 66, č. 2 (2011), s. 275-281. ISSN 0006-3088 R&D Projects: GA ČR(CZ) GA526/06/0556 Institutional research plan: CEZ:AV0Z60050516 Keywords : nitrogen * drought * above-ground biomass Subject RIV: EF - Botanics Impact factor: 0.557, year: 2011

  13. Examining the potential of Sentinel-2 MSI spectral resolution in quantifying above ground biomass across different fertilizer treatments

    Sibanda, Mbulisi; Mutanga, Onisimo; Rouget, Mathieu

    2015-12-01

    The major constraint in understanding grass above ground biomass variations using remotely sensed data are the expenses associated with the data, as well as the limited number of techniques that can be applied to different management practices with minimal errors. New generation multispectral sensors such as Sentinel 2 Multispectral Imager (MSI) are promising for effective rangeland management due to their unique spectral bands and higher signal to noise ratio. This study resampled hyperspectral data to spectral resolutions of the newly launched Sentinel 2 MSI and the recently launched Landsat 8 OLI for comparison purposes. Using Sparse partial least squares regression, the resampled data was applied in estimating above ground biomass of grasses treated with different fertilizer combinations of ammonium sulfate, ammonium nitrate, phosphorus and lime as well as unfertilized experimental plots. Sentinel 2 MSI derived models satisfactorily performed (R2 = 0.81, RMSEP = 1.07 kg/m2, RMSEP_rel = 14.97) in estimating grass above ground biomass across different fertilizer treatments relative to Landsat 8 OLI (Landsat 8 OLI: R2 = 0.76, RMSEP = 1.15 kg/m2, RMSEP_rel = 16.04). In comparison, hyperspectral data derived models exhibited better grass above ground biomass estimation across complex fertilizer combinations (R2 = 0.92, RMSEP = 0.69 kg/m2, RMSEP_rel = 9.61). Although Sentinel 2 MSI bands and indices better predicted above ground biomass compared with Landsat 8 OLI bands and indices, there were no significant differences (α = 0.05) in the errors of prediction between the two new generational sensors across all fertilizer treatments. The findings of this study portrays Sentinel 2 MSI and Landsat 8 OLI as promising remotely sensed datasets for regional scale biomass estimation, particularly in resource scarce areas.

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

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

  15. Structure and distribution of glandular and non-glandular trichomes on above-ground organs in Inula helenium L. (Asteraceae

    Aneta Sulborska

    2014-01-01

    Full Text Available Micromorphology and distribution of glandular and non-glandular trichomes on the above-ground organs of Inula helenium L. were investigated using light and scanning electron microscopy (SEM. Two types of biseriate glandular trichomes, i.e. sessile and stalk hairs, and non-glandular trichomes were recorded. Sessile glandular trichomes were found on all examined I. helenium organs (with their highest density on the abaxial surface of leaves and disk florets, and on stems, whereas stalk glandular trichomes were found on leaves and stems. Sessile trichomes were characterised by a slightly lower height (58–103 μm and width (32–35 μm than the stalk trichomes (62–111 μm x 31–36 μm. Glandular hairs were composed of 5–7 (sessile trichomes or 6–9 (stalk trichomes cell tiers. Apical trichome cell tiers exhibited features of secretory cells. Secretion was accumulated in subcuticular space, which expanded and ruptured at the top, and released its content. Histochemical assays showed the presence of lipids and polyphenols, whereas no starch was detected. Non-glandular trichomes were seen on involucral bracts, leaves and stems (more frequently on involucral bracts. Their structure comprised 2–9 cells; basal cells (1–6 were smaller and linearly arranged, while apical cells had a prozenchymatous shape. The apical cell was the longest and sharply pointed. Applied histochemical tests revealed orange-red (presence of lipids and brow colour (presence of polyphenols in the apical cells of the trichomes. This may suggest that beside their protective role, the trichomes may participate in secretion of secondary metabolites.

  16. Sensitivity of Above-Ground Biomass Estimates to Height-Diameter Modelling in Mixed-Species West African Woodlands.

    Valbuena, Rubén; Heiskanen, Janne; Aynekulu, Ermias; Pitkänen, Sari; Packalen, Petteri

    2016-01-01

    It has been suggested that above-ground biomass (AGB) inventories should include tree height (H), in addition to diameter (D). As H is a difficult variable to measure, H-D models are commonly used to predict H. We tested a number of approaches for H-D modelling, including additive terms which increased the complexity of the model, and observed how differences in tree-level predictions of H propagated to plot-level AGB estimations. We were especially interested in detecting whether the choice of method can lead to bias. The compared approaches listed in the order of increasing complexity were: (B0) AGB estimations from D-only; (B1) involving also H obtained from a fixed-effects H-D model; (B2) involving also species; (B3) including also between-plot variability as random effects; and (B4) involving multilevel nested random effects for grouping plots in clusters. In light of the results, the modelling approach affected the AGB estimation significantly in some cases, although differences were negligible for some of the alternatives. The most important differences were found between including H or not in the AGB estimation. We observed that AGB predictions without H information were very sensitive to the environmental stress parameter (E), which can induce a critical bias. Regarding the H-D modelling, the most relevant effect was found when species was included as an additive term. We presented a two-step methodology, which succeeded in identifying the species for which the general H-D relation was relevant to modify. Based on the results, our final choice was the single-level mixed-effects model (B3), which accounts for the species but also for the plot random effects reflecting site-specific factors such as soil properties and degree of disturbance. PMID:27367857

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

    Anderson, L. O.; Malhi, Y.; Ladle, R. J.; Aragão, L. E. O. C.; Shimabukuro, Y.; Phillips, O. L.; Baker, T.; Costa, A. C. L.; Espejo, J. S.; Higuchi, N.; Laurance, W. F.; López-González, G.; Monteagudo, A.; Núñez-Vargas, P.; Peacock, J.; Quesada, C. A.; Almeida, S.

    2009-09-01

    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.

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

    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.

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

    L. O. Anderson

    2009-02-01

    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 alluvial terrain forest, 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.

  20. A comparison of two above-ground biomass estimation techniques integrating satellite-based remotely sensed data and ground data for tropical and semiarid forests in Puerto Rico

    Iiames, J. S.; Riegel, J.; Lunetta, R.

    2013-12-01

    Two above-ground forest biomass estimation techniques were evaluated for the United States Territory of Puerto Rico using predictor variables acquired from satellite based remotely sensed data and ground data from the U.S. Department of Agriculture Forest Inventory Analysis (FIA) program. The U.S. Environmental Protection Agency (EPA) estimated above-ground forest biomass implementing methodology first posited by the Woods Hole Research Center developed for conterminous United States (National Biomass and Carbon Dataset [NBCD2000]). For EPA's effort, spatial predictor layers for above-ground biomass estimation included derived products from the U.S. Geologic Survey (USGS) National Land Cover Dataset 2001 (NLCD) (landcover and canopy density), the USGS Gap Analysis Program (forest type classification), the USGS National Elevation Dataset, and the NASA Shuttle Radar Topography Mission (tree heights). In contrast, the U.S. Forest Service (USFS) biomass product integrated FIA ground-based data with a suite of geospatial predictor variables including: (1) the Moderate Resolution Imaging Spectrometer (MODIS)-derived image composites and percent tree cover; (2) NLCD land cover proportions; (3) topographic variables; (4) monthly and annual climate parameters; and (5) other ancillary variables. Correlations between both data sets were made at variable watershed scales to test level of agreement. Notice: This work is done in support of EPA's Sustainable Healthy Communities Research Program. The U.S EPA funded and conducted the research described in this paper. Although this work was reviewed by the EPA and has been approved for publication, it may not necessarily reflect official Agency policy. Mention of any trade names or commercial products does not constitute endorsement or recommendation for use.

  1. Above ground biomass estimation from lidar and hyperspectral airbone data in West African moist forests.

    Vaglio Laurin, Gaia; Chen, Qi; Lindsell, Jeremy; Coomes, David; Cazzolla-Gatti, Roberto; Grieco, Elisa; Valentini, Riccardo

    2013-04-01

    The development of sound methods for the estimation of forest parameters such as Above Ground Biomass (AGB) and the need of data for different world regions and ecosystems, are widely recognized issues due to their relevance for both carbon cycle modeling and conservation and policy initiatives, such as the UN REDD+ program (Gibbs et al., 2007). The moist forests of the Upper Guinean Belt are poorly studied ecosystems (Vaglio Laurin et al. 2013) but their role is important due to the drier condition expected along the West African coasts according to future climate change scenarios (Gonzales, 2001). Remote sensing has proven to be an effective tool for AGB retrieval when coupled with field data. Lidar, with its ability to penetrate the canopy provides 3D information and best results. Nevertheless very limited research has been conducted in Africa tropical forests with lidar and none to our knowledge in West Africa. Hyperspectral sensors also offer promising data, being able to evidence very fine radiometric differences in vegetation reflectance. Their usefulness in estimating forest parameters is still under evaluation with contrasting findings (Andersen et al. 2008, Latifi et al. 2012), and additional studies are especially relevant in view of forthcoming satellite hyperspectral missions. In the framework of the EU ERC Africa GHG grant #247349, an airborne campaign collecting lidar and hyperspectral data has been conducted in March 2012 over forests reserves in Sierra Leone and Ghana, characterized by different logging histories and rainfall patterns, and including Gola Rainforest National Park, Ankasa National Park, Bia and Boin Forest Reserves. An Optech Gemini sensor collected the lidar dataset, while an AISA Eagle sensor collected hyperspectral data over 244 VIS-NIR bands. The lidar dataset, with a point density >10 ppm was processed using the TIFFS software (Toolbox for LiDAR Data Filtering and Forest Studies)(Chen 2007). The hyperspectral dataset, geo

  2. Estimation of above ground biomass by using multispectral data for Evergreen Forest in Phu Hin Rong Kla National Park, Thailand

    Tropical forest is the most important and largest source for stocking CO2 from the atmosphere which might be one of the main sources of carbon emission, global warming and climate change in recent decades. There are two main objectives of this study. The first one is to establish a relationship between above ground biomass and vegetation indices and the other is to evaluate above ground biomass and carbon sequestration for evergreen forest areas in Phu Hin Rong Kla National park, Thailand. Random sampling design based was applied for calculating the above ground biomass at stand level in the selected area by using Brown and Tsutsumi allometric equations. Landsat 7 ETM+ data in February 2009 was used. Support Vector Machine (SVM) was applied for identifying evergreen forest area. Forty-three of vegetation indices and image transformations were used for finding the best correlation with forest stand biomass. Regression analysis was used to investigate the relationship between the biomass volume at stand level and digital data from the satellite image. TM51 which derived from Tsutsumi allometric equation was the highest correlation with stand biomass. Normalized Difference Vegetation Index (NDVI) was not the best correlation in this study. The best biomass estimation model was from TM51 and ND71 (R2 =0.658). The totals of above ground biomass and carbon sequestration were 112,062,010 ton and 56,031,005 ton respectively. The application of this study would be quite useful for understanding the terrestrial carbon dynamics and global climate change. (author)

  3. Forest Structure, Composition and Above Ground Biomass of Tree Community in Tropical Dry Forests of Eastern Ghats, India

    Sudam Charan SAHU

    2016-03-01

    Full Text Available The study of biomass, structure and composition of tropical forests implies also the investigation of forest productivity, protection of biodiversity and removal of CO2 from the atmosphere via C-stocks. The hereby study aimed at understanding the forest structure, composition and above ground biomass (AGB of tropical dry deciduous forests of Eastern Ghats, India, where as a total of 128 sample plots (20 x 20 meters were laid. The study showed the presence of 71 tree species belonging to 57 genera and 30 families. Dominant tree species was Shorea robusta with an importance value index (IVI of 40.72, while Combretaceae had the highest family importance value (FIV of 39.01. Mean stand density was 479 trees ha-1 and a basal area of 15.20 m2 ha-1. Shannon’s diversity index was 2.01 ± 0.22 and Simpson’s index was 0.85 ± 0.03. About 54% individuals were in the size between 10 and 20 cm DBH, indicating growing forests. Mean above ground biomass value was 98.87 ± 68.8 Mg ha-1. Some of the dominant species that contributed to above ground biomass were Shorea robusta (17.2%, Madhuca indica (7.9%, Mangifera indica (6.9%, Terminalia alata (6.9% and Diospyros melanoxylon (4.4%, warranting extra efforts for their conservation. The results suggested that C-stocks of tropical dry forests can be enhanced by in-situ conserving the high C-density species and also by selecting these species for afforestation and stand improvement programs. Correlations were computed to understand the relationship between above ground biomass, diversity indices, density and basal area, which may be helpful for implementation of REDD+ (reduce emissions from deforestation and forest degradation, and foster conservation, sustainable management of forests and enhancement of forest carbon stocks scheme.

  4. Forest Structure, Composition and Above Ground Biomass of Tree Community in Tropical Dry Forests of Eastern Ghats, India

    Sudam Charan SAHU; Ravindranath, N.H.; Suresh, H. S.

    2016-01-01

    The study of biomass, structure and composition of tropical forests implies also the investigation of forest productivity, protection of biodiversity and removal of CO2 from the atmosphere via C-stocks. The hereby study aimed at understanding the forest structure, composition and above ground biomass (AGB) of tropical dry deciduous forests of Eastern Ghats, India, where as a total of 128 sample plots (20 x 20 meters) were laid. The study showed the presence of 71 tree species belonging to 57 ...

  5. The nuclear dissuasion without tests

    Since the signature of the french treaty against the nuclear tests (Tice) in 1995, the french engineers must used the simulation to warrant the performance and the safety of weapons. This paper recalls the historical aspects of the french nuclear tests and presents the technological and scientific resources to simulate a nuclear weapon operating. a special interest is given to the computer TERA. (A.L.B.)

  6. A comprehensive nuclear test ban

    The conclusion of a comprehensive nuclear test ban is of critical importance for the future of arms limitation and disarmament. As the 1980 report of the Secretary-General concluded, a comprehensive nuclear test ban is regarded as the first and most urgent step towards the cessation of the nuclear arms race and, in particular, of its qualitative aspects. It could serve as an important measure for the non-proliferation of nuclear weapons, both vertical and horizontal. It would have a major arms limitation impact in that it would make it difficult, if not impossible, to develop new designs of nuclear weapons and would also place constraints on the modification of existing weapon designs. The permanent cessation of all nuclear-weapon tests has long been sought by the world community and its achievement would be an event of great international significance

  7. Above-ground Woody Biomass Production of Short-rotation Populus Plantations on Agricultural Land in Sweden

    Karacic, Almir; Verwijst, Theo; Weih, Martin [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Short Rotation Forestry

    2003-09-01

    Although poplars are widely grown in short-rotation forestry in many countries, little is known about poplar growth performance in Sweden. In this study, above-ground biomass production was estimated for several hybrid aspen and poplar clones planted at different initial density at five locations across Sweden. Biomass assessments were based on allometric relationships between total above-ground woody dry weight and the diameter at breast height. According to a common harvest practice, tree biomass was partitioned into pulpwood and biomass for energy purposes. The percentage of pulpwood was strongly determined by clone for DBH >10 cm. The mean annual increment ranged from 3.3 /ha/yr for balsam poplar in the north to 9.2 Mg/ha/yr for 9-yr-old 'Boelare' in southern Sweden. At the same age, hybrid aspen reached 7.9 Mg/ha/yr. The results suggest that poplars and hybrid aspen are superior as biomass producers compared with tree species commonly grown on agricultural land at these latitudes. The results are discussed in the light of future wood supply for pulpwood and energy purposes in Sweden.

  8. Modeling the spatial distribution of above-ground carbon in Mexican coniferous forests using remote sensing and a geostatistical approach

    Galeana-Pizaña, J. Mauricio; López-Caloca, Alejandra; López-Quiroz, Penélope; Silván-Cárdenas, José Luis; Couturier, Stéphane

    2014-08-01

    Forest conservation is considered an option for mitigating the effect of greenhouse gases on global climate, hence monitoring forest carbon pools at global and local levels is important. The present study explores the capability of remote-sensing variables (vegetation indices and textures derived from SPOT-5; backscattering coefficient and interferometric coherence of ALOS PALSAR images) for modeling the spatial distribution of above-ground biomass in the Environmental Conservation Zone of Mexico City. Correlation and spatial autocorrelation coefficients were used to select significant explanatory variables in fir and pine forests. The correlation for interferometric coherence in HV polarization was negative, with correlations coefficients r = -0.83 for the fir and r = -0.75 for the pine forests. Regression-kriging showed the least root mean square error among the spatial interpolation methods used, with 37.75 tC/ha for fir forests and 29.15 tC/ha for pine forests. The results showed that a hybrid geospatial method, based on interferometric coherence data and a regression-kriging interpolator, has good potential for estimating above-ground biomass carbon.

  9. Statistical analysis of indoor radon concentrations in a reinforced concrete building with three stories above ground and one basement

    It is important to understand 222Rn concentrations in dwellings precisely for dose assessment. 222Rn concentrations were continuously measured in a reinforced-concrete house in Tokyo with three stories above ground and one basement for seven years, from October 1988 to September 1995. In the basement, temperature and humidity were also measured, which were used for analyzing the seasonal variation of the 222Rn concentration and its relationship with environmental factors. 222Rn concentrations on the 2nd and 3rd floors showed a statistically significant seasonal variation, i.e., higher in winter and lower in summer, but those on the 1st floor did not show any significant seasonal variation. The 222Rn concentration in the basement showed a reverse seasonal variation, i.e., higher in summer and lower in winter. The 222Rn concentrations on each floor showed a drastic decrease after the renewal of the dehumidifier in the basement, which suggests that the 222Rn concentration in the basement has an influence on that in the rooms above ground. A multiple regression analysis suggested that the 222Rn concentration in the basement and its seasonal variation can be expressed with statistical significance by the linear combination of temperature, humidity and atmospheric pressure. It was also revealed that the 222Rn concentration on the 1st floor can be expressed by the linear combination of the concentrations in the basement, 2nd and 3rd floors. (author)

  10. Development of Allometric Equations for Estimating Above-Ground Liana Biomass in Tropical Primary and Secondary Forests, Malaysia

    Patrick Addo-Fordjour

    2013-01-01

    Full Text Available The study developed allometric equations for estimating liana stem and total above-ground biomass in primary and secondary forests in the Penang National Park, Penang, Malaysia. Using biomass-diameter-length data of 60 liana individuals representing 15 species, allometric equations were developed for liana stem biomass and total above-ground biomass (TAGB. Three types of allometric equations were developed: models fitted to untransformed, weighted, and log-transformed (log10 data. There was a significant linear relationship between biomass and the predictors (diameter, length, and/or their combinations. The same set of models was developed for primary and secondary forests due to absence of differences in regression line slopes of the forests (ANCOVA: . The coefficients of determination values of the models were high (stem: 0.861 to 0.990; TAGB: 0.900 to 0.992. Generally, log-transformed models showed better fit (Furnival's index, FI 0.5. A comparison of the best TAGB model in this study (based on FI with previously published equations indicated that most of the equations significantly ( overestimated TAGB of lianas. However, a previous equation from Southeast Asia estimated TAGB similar to that of the current equation (. Therefore, regional or intracontinental equations should be preferred to intercontinental equations when estimating liana biomass.

  11. The Interpolation Method for Estimating the Above-Ground Biomass Using Terrestrial-Based Inventory

    I Nengah Surati Jaya

    2014-08-01

    Full Text Available This paper examined several methods for interpolating biomass on logged-over dry land forest using terrestrial-based forest inventory in Labanan, East Kalimantan and Lamandau, Kota Wringing Barat, Central Kalimantan. The plot-distances examined was 1,000−1,050 m for Labanan and 1,000−899m for Lawanda. The main objective of this study was to obtain the best interpolation method having the most accurate prediction on spatial distribution of forest biomass for dry land forest. Two main interpolation methods were examined: (1 deterministic approach using the IDW method and (2 geo-statistics approach using Kriging with spherical, circular, linear, exponential, and Gaussian models. The study results at both sites consistently showed that the IDW method was better than the Kriging method for estimating the spatial distribution of biomass. The validation results using chi-square test showed that the IDW interpolation provided accurate biomass estimation. Using the percentage of mean deviation value (MD(%, it was also recognized that the IDWs with power parameter (p of 2 provided relatively low value , i.e., only 15% for Labanan, East Kalimantan Province and 17% for Lamandau, Kota Wringing Barat Central Kalimantan Province. In general, IDW interpolation method provided better results than the Kriging, where the Kriging method provided MD(% of about 27% and 21% for Lamandau and Labanan sites, respectively.

  12. The Interpolation Method for Estimating the Above-Ground Biomass Using Terrestrial-Based Inventory

    I Nengah Surati Jaya

    2014-09-01

    Full Text Available This paper examined several methods for interpolating biomass on logged-over dry land forest using terrestrial-based forest inventory in Labanan, East Kalimantan and Lamandau, Kota Wringing Barat, Central Kalimantan.  The plot-distances examined was 1,000−1,050 m for Labanan and 1,000−899m for Lawanda.  The main objective of this study was to obtain the best interpolation method having the most accurate prediction on spatial distribution of forest biomass for dry land forest. Two main interpolation methods were examined: (1 deterministic approach using the IDW method and (2 geo-statistics approach  using Kriging with spherical, circular, linear, exponential, and Gaussian models.   The study results at both sites consistently showed that the IDW method was better than the Kriging method for estimating the spatial distribution of biomass.  The validation results using chi-square test showed that the IDW interpolation provided accurate biomass estimation.   Using the percentage of mean deviation value (MD(%, it was also recognized that the IDWs with power parameter (p of 2 provided relatively low value , i.e., only 15% for Labanan, East Kalimantan Province and 17% for Lamandau, Kota Wringing Barat Central Kalimantan Province. In general, IDW interpolation method provided better results than the Kriging, where the Kriging method provided MD(% of about 27% and 21% for Lamandau and Labanan sites, respectively.Keywords:  deterministic, geostatistics, IDW, Kriging, above-groung biomass

  13. Nuclear Test-Experimental Science

    Fiscal year 1988 has been a significant, rewarding, and exciting period for Lawrence Livermore National Laboratory's nuclear testing program. It was significant in that the Laboratory's new director chose to focus strongly on the program's activities and to commit to a revitalized emphasis on testing and the experimental science that underlies it. It was rewarding in that revolutionary new measurement techniques were fielded on recent important and highly complicated underground nuclear tests with truly incredible results. And it was exciting in that the sophisticated and fundamental problems of weapons science that are now being addressed experimentally are yielding new challenges and understanding in ways that stimulate and reward the brightest and best of scientists. During FY88 the program was reorganized to emphasize our commitment to experimental science. The name of the program was changed to reflect this commitment, becoming the Nuclear Test-Experimental Science (NTES) Program

  14. A first map of tropical Africa's above-ground biomass derived from satellite imagery

    Baccini, A; Laporte, N; Goetz, S J; Sun, M [Woods Hole Research Center, 149 Woods Hole Road, Falmouth, MA 02540 (United States); Dong, H [Atmospheric Sciences Division, Brookhaven National Laboratory, Upton, NY 11973 (United States)], E-mail: abaccini@whrc.org

    2008-10-15

    Observations from the moderate resolution imaging spectroradiometer (MODIS) were used in combination with a large data set of field measurements to map woody above-ground biomass (AGB) across tropical Africa. We generated a best-quality cloud-free mosaic of MODIS satellite reflectance observations for the period 2000-2003 and used a regression tree model to predict AGB at 1 km resolution. Results based on a cross-validation approach show that the model explained 82% of the variance in AGB, with a root mean square error of 50.5 Mg ha{sup -1} for a range of biomass between 0 and 454 Mg ha{sup -1}. Analysis of lidar metrics from the Geoscience Laser Altimetry System (GLAS), which are sensitive to vegetation structure, indicate that the model successfully captured the regional distribution of AGB. The results showed a strong positive correlation (R{sup 2} = 0.90) between the GLAS height metrics and predicted AGB.

  15. Long-term changes in above ground biomass after disturbance in a neotropical dry forest, Hellshire Hills, Jamaica

    Niño, Milena; McLaren, Kurt P.; Meilby, Henrik;

    2014-01-01

    We used data from experimental plots (control, partially cut and clear-cut) established in 1998, in a tropical dry forest (TDF) in Jamaica, to assess changes in above ground biomass (AGB) 10 years after disturbance. The treatments reduced AGB significantly in 1999 (partially cut: 37.6 %, clear-cu.......4 years for the clear-cut plots to recover pre-treatment AGB; this is significantly longer than AGB recovery time for some successional rainforests on abandoned pastures/farmland. Consequently, this TDF may not be as resilient as tropical rainforests.......-cut: 94.4 %) and after 10 years, AGB did not recover overall, nor did it recover in the clear-cut plots. Partially cut plots, however, recovered the lost AGB in 10 years via growth of uncut trees, which contributed significantly to biomass recovery, with only minor contributions from recruited trees and...

  16. Tree Species Composition, Diversity and Above Ground Biomass of Two Forest Types at Redang Island, Peninsula Malaysia

    Mahmud KHAIRIL

    2013-02-01

    Full Text Available A study was conducted to determine the tree species composition, diversity and above ground biomass at Redang Island, Terengganu. Two plots of 0.1 ha were established at the inland forest and coastal forest of the island. As the result, a total of 387 trees ≥ 5 diameters at breast height (DBH were recorded. The coastal forest recorded 167 individuals representing 48 species from 37 genera and 26 families while the inland forest had 220 individuals representing 50 species from 43 genera and 25 families. Shorea glauca (Dipterocarpaceae was the most important species at the coastal forest with a Species Importance Value Index (SIVi of 10.5 % while Dipterocarpus costulatus (Dipterocarpaceae was the most important species at the inland forest with 13.8 %. Dipterocarpaceae was the most important family in both forest plots with FIVi at 20.4 % in the coastal and 21.5 % in the inland forest. The Shannon-Weiner Diversity Index (H’ was considered high in both forest plots with 3.4 (H’max = 3.9 at the coastal forest and 3.5 (H’max = 4.0 at the inland forest. Sorenson’s Community Similarity Coefficient (CCs showed that tree species communities between the two forest plots had moderate similarity with CC = 0.5. The Shannon Evenness Index (J’ in the two forest plots was 0.89. The total above ground biomass at the coastal forest was 491 t/ha and at the inland forest it was 408 t/ha. From all the species recorded in this study, 11 species were listed as threatened species by IUCN Red Data Book, of which four were listed as endangered and critically endangered, six were listed as lower risk and one species was listed as vulnerable.

  17. Predictive modeling of hazardous waste landfill total above-ground biomass using passive optical and LIDAR remotely sensed data

    Hadley, Brian Christopher

    This dissertation assessed remotely sensed data and geospatial modeling technique(s) to map the spatial distribution of total above-ground biomass present on the surface of the Savannah River National Laboratory's (SRNL) Mixed Waste Management Facility (MWMF) hazardous waste landfill. Ordinary least squares (OLS) regression, regression kriging, and tree-structured regression were employed to model the empirical relationship between in-situ measured Bahia (Paspalum notatum Flugge) and Centipede [Eremochloa ophiuroides (Munro) Hack.] grass biomass against an assortment of explanatory variables extracted from fine spatial resolution passive optical and LIDAR remotely sensed data. Explanatory variables included: (1) discrete channels of visible, near-infrared (NIR), and short-wave infrared (SWIR) reflectance, (2) spectral vegetation indices (SVI), (3) spectral mixture analysis (SMA) modeled fractions, (4) narrow-band derivative-based vegetation indices, and (5) LIDAR derived topographic variables (i.e. elevation, slope, and aspect). Results showed that a linear combination of the first- (1DZ_DGVI), second- (2DZ_DGVI), and third-derivative of green vegetation indices (3DZ_DGVI) calculated from hyperspectral data recorded over the 400--960 nm wavelengths of the electromagnetic spectrum explained the largest percentage of statistical variation (R2 = 0.5184) in the total above-ground biomass measurements. In general, the topographic variables did not correlate well with the MWMF biomass data, accounting for less than five percent of the statistical variation. It was concluded that tree-structured regression represented the optimum geospatial modeling technique due to a combination of model performance and efficiency/flexibility factors.

  18. Introduction to nuclear test engineering

    The basic information in this report is from a vu-graph presentation prepared to acquaint new or prospective employees with the Nuclear Test Engineering Division (NTED). Additional information has been added here to enhance a reader's understanding when reviewing the material after hearing the presentation, or in lieu of attending a presentation

  19. The effects of nuclear tests

    The United States, the Sovjet Union, Britain, France and China have so far completed slightly over 2,000 nuclear tests. At first, the tests were mainly conducted in the atmosphere. The number of atmospheric tests done is slightly over 500. Explosions detonated in the atmosphere were dangerous to all those participating the tests -researchers, workers and military personnel - as well as to the inhabitants living near the test sites. The first hydrogen bomb test carried out by the United States on Bikini Atoll in 1954 caused radioactive fallout that contaminated the nearby atolls and made the crew of a Japanese fishing vessel fall ill. Soldiers participating in military drills conducted in connection with the tests were also exposed to the risks of the atmospheric explosions. Only a few atmospheric tests had direct health effects, but it is still being debated whether the resulting radiation doses affected the diseases that have surfaced later. The veil of secrecy kept up by all countries with nuclear weapons has hampered any investigations into the matter for decades. Nevertheless, in the last few years, some victims of the tests have been paid damages. (orig.) (1 fig.)

  20. Above Ground Leafless Woody Biomass and Nutrient Content within Different Compartments of a P. maximowicii × P. trichocarpa Poplar Clone

    Heinrich Spiecker

    2013-06-01

    Full Text Available In this study the quantification of biomass within all relevant compartments of a three-year-old poplar clone (P. maximowicii × P. trichocarpa planted on abandoned agricultural land at a density of 5000 trees ha−1 is presented. A total of 30 trees within a diameter range of 1.8 cm to 8.9 cm, at breast height (dbh at 1.3 m, were destructively sampled. In order to analyze the biomass, the complete tree, stem, as well as all branches, were divided into 1 cm diameter classes and all buds from the trees were completely removed. Total yield was calculated as 11.7 odt ha−1 year−1 (oven dry tonnes per hectare and year. Branches constituted 22.2% of total dry leafless biomass and buds 2.0%. The analyses revealed a strong correlation of the dry weight for all the three compartments with diameter at breast height. Debarked sample discs were used to obtain a ratio between wood and bark. Derived from these results, a model was developed to calculate the biomass of bark with dbh as the predictor variable. Mean bark percentage was found to be 16.8% of above ground leafless biomass. The results concur that bark percentage decreases with increasing tree diameter, providing the conclusion that larger trees contain a lower bark proportion, and thus positively influence the quality of the end product while consequently reducing the export of nutrients from site.

  1. Mapping Above-Ground Biomass in a Tropical Forest in Cambodia Using Canopy Textures Derived from Google Earth

    Minerva Singh

    2015-04-01

    Full Text Available This study develops a modelling framework for utilizing very high-resolution (VHR aerial imagery for monitoring stocks of above-ground biomass (AGB in a tropical forest in Southeast Asia. Three different texture-based methods (grey level co-occurrence metric (GLCM, Gabor wavelets and Fourier-based textural ordination (FOTO were used in conjunction with two different machine learning (ML-based regression techniques (support vector regression (SVR and random forest (RF regression. These methods were implemented on both 50-cm resolution Digital Globe data extracted from Google Earth™ (GE and 8-cm commercially obtained VHR imagery. This study further examines the role of forest biophysical parameters, such as ground-measured canopy cover and vertical canopy height, in explaining AGB distribution. Three models were developed using: (i horizontal canopy variables (i.e., canopy cover and texture variables plus vertical canopy height; (ii horizontal variables only; and (iii texture variables only. AGB was variable across the site, ranging from 51.02 Mg/ha to 356.34 Mg/ha. GE-based AGB estimates were comparable to those derived from commercial aerial imagery. The findings demonstrate that novel use of this array of texture-based techniques with GE imagery can help promote the wider use of freely available imagery for low-cost, fine-resolution monitoring of forests parameters at the landscape scale.

  2. Tree density on a vegetated uranium mill tailings site and associated estimates of Ra-226 in above ground biomass

    The transfer of Ra-226 to the terrestrial pathway will depend on the uptake by indigenous species which colonize dry areas of inactive or abandoned uranium mill tailings sites. The density of trembling aspen and white birch, their heights and biomass values, have been determined 10 to 15 years after revegetation. In addition the percentage composition of the ground cover for herbs, shrubs and grasses is evaluated. For aspens of less than 1 m in height, the density of 0.0536 trees/m2 was considerably higher than for birches of the same height with 0.0097 trees/m2. As tree heights increase the number of trees/m2 decrease to 0.0049 and 0.0010 respectively for 3 to 4 m tall trees. Trees taller than 4 m were rarely found. The ground cover biomass (approximately 125 g/m2) consisted generally of two types; either shrubs were dominant or herbs and grasses prevailed. From Ra-226 concentrations in different above-ground biomass components and the average composition of the vegetation on one square metre, transfer values were estimated. Annual transfer by herbal biomass (leaves, herbs and grasses) ranged from 330 to 760 pCi/m2. The standing crop of woody biomass was estimated to range from 450 to 1700 pCi/m2

  3. Above-ground biomass estimation of tuberous bulrush ( Bolboschoenus planiculmis) in mudflats using remotely sensed multispectral image

    Kim, Ji Yoon; Im, Ran-Young; Do, Yuno; Kim, Gu-Yeon; Joo, Gea-Jae

    2016-03-01

    We present a multivariate regression approach for mapping the spatial distribution of above-ground biomass (AGB) of B. planiculmis using field data and coincident moderate spatial resolution satellite imagery. A total of 232 ground sample plots were used to estimate the biomass distribution in the Nakdong River estuary. Field data were overlain and correlated with digital values from an atmospherically corrected multispectral image (Landsat 8). The AGB distribution was derived using empirical models trained with field-measured AGB data. The final regression model for AGB estimation was composed using the OLI3, OLI4, and OLI7 spectral bands. The Pearson correlation between the observed and predicted biomass was significant (R = 0.84, p coefficient value: 53.4%) and revealed a negative relationship with the AGB biomass. The total distribution area of B. planiculmis was 1,922,979 m2. Based on the model estimation, the total AGB had a dry weight (DW) of approximately 298.2 tons. The distribution of high biomass stands (> 200 kg DW/900 m2) constituted approximately 23.91% of the total vegetated area. Our findings suggest the expandability of remotely sensed products to understand the distribution pattern of estuarine plant productivity at the landscape level.

  4. Nitrogen mediates above-ground effects of ozone but not below-ground effects in a rhizomatous sedge

    Jones, M.L.M., E-mail: lj@ceh.ac.u [Centre for Ecology and Hydrology (CEH), Environment Centre Wales, Deiniol Road, Bangor, LL57 2UW Wales (United Kingdom); Hodges, G. [AMEC, Earth and Environmental UK Ltd, Unit 1, Trinity Place, Thames St, Weybridge, Surrey KT13 8JB (United Kingdom); Mills, G. [Centre for Ecology and Hydrology (CEH), Environment Centre Wales, Deiniol Road, Bangor, LL57 2UW Wales (United Kingdom)

    2010-02-15

    Ozone and atmospheric nitrogen are co-occurring pollutants with adverse effects on natural grassland vegetation. Plants of the rhizomatous sedge Carex arenaria were exposed to four ozone regimes representing increasing background concentrations (background-peak): 10-30, 35-55, 60-80 and 85-105 ppb ozone at two nitrogen levels: 12 and 100 kg N ha{sup -1} yr{sup -1}. Ozone increased the number and proportion of senesced leaves, but not overall leaf number. There was a clear nitrogen x ozone interaction with high nitrogen reducing proportional senescence in each treatment and increasing the ozone dose (AOT40) at which enhanced senescence occurred. Ozone reduced total biomass due to significant effects on root biomass. There were no interactive effects on shoot:root ratio. Rhizome tissue N content was increased by both nitrogen and ozone. Results suggest that nitrogen mediates above-ground impacts of ozone but not impacts on below-ground resource translocation. This may lead to complex interactive effects between the two pollutants on natural vegetation. - Nitrogen alters threshold of ozone-induced senescence, but not below-ground resource allocation.

  5. Reflectance of blue, green, red and near infrared radiation from wetland vegetation used in a model discriminating live and dead above ground biomass

    Field measurements of canopy reflectance of wetland vegetation in the blue (450 ran), green (548 nm), red (655 nm) and NIR (805 nm) wavebands were correlated with plant biomass variables. Negative relationships, asymptotic in nature, were observed between visible wavebands, canopy reflectance and total live biomass as well as green biomass, with correlation coefficients r between −0·52 and −0·93. Curvilinear relations were observed between NIR canopy reflectance and total live biomass as well as green biomass, with r between 0·39 and 0·88. Different normalization indices (NIR blue−1, NIR red−1, VI, PI and NIRlbio) were tested and positive relations between these indices and total live biomass and green biomass were observed, with r between 0·69 and 0·96. Inverse relations of an asymptotic nature were observed between dead biomass as a percentage of total biomass and of green biomass, with r between 0·90 and 0·91. A model discriminating live and dead above-ground biomass was developed to improve correlations between canopy reflectance and biomass variables. The model nearly doubled the correlation coefficient between reflectance and green biomass for a canopy containing large amounts of interfering dead biomass, but did not change this correlation for a canopy containing small amounts of dead biomass. (author)

  6. Lasting effects of climate disturbance on perennial grassland above-ground biomass production under two cutting frequencies.

    Zwicke, Marine; Alessio, Giorgio A; Thiery, Lionel; Falcimagne, Robert; Baumont, René; Rossignol, Nicolas; Soussana, Jean-François; Picon-Cochard, Catherine

    2013-11-01

    Climate extremes can ultimately reshape grassland services such as forage production and change plant functional type composition. This 3-year field research studied resistance to dehydration and recovery after rehydration of plant community and plant functional types in an upland perennial grassland subjected to climate and cutting frequency (Cut+, Cut-) disturbances by measuring green tissue percentage and above-ground biomass production (ANPP). In year 1, a climate disturbance gradient was applied by co-manipulating temperature and precipitation. Four treatments were considered: control and warming-drought climatic treatment, with or without extreme summer event. In year 2, control and warming-drought treatments were maintained without extreme. In year 3, all treatments received ambient climatic conditions. We found that the grassland community was very sensitive to dehydration during the summer extreme: aerial senescence reached 80% when cumulated climatic water balance fell to -156 mm and biomass declined by 78% at the end of summer. In autumn, canopy greenness and biomass totally recovered in control but not in the warming-drought treatment. However ANPP decreased under both climatic treatments, but the effect was stronger on Cut+ (-24%) than Cut- (-15%). This decline was not compensated by the presence of three functional types because they were negatively affected by the climatic treatments, suggesting an absence of buffering effect on grassland production. In the following 2 years, lasting effects of climate disturbance on ANPP were observable. The unexpected stressful conditions of year 3 induced a decline in grassland production in the Cut+ control treatment. The fact that this treatment cumulated higher (45%) N export over the 3 years suggests that N plays a key role in ANPP stability. As ANPP in this mesic perennial grassland did not show engineering resilience, long-term experimental manipulation is needed. Infrequent mowing appears more

  7. Above-Ground Dimensions and Acclimation Explain Variation in Drought Mortality of Scots Pine Seedlings from Various Provenances

    Seidel, Hannes; Menzel, Annette

    2016-01-01

    Seedling establishment is a critical part of the life cycle, thus seedling survival might be even more important for forest persistence under recent and future climate change. Scots pine forests have been disproportionally more affected by climate change triggered forest-dieback. Nevertheless, some Scots pine provenances might prove resilient to future drought events because of the species’ large distributional range, genetic diversity, and adaptation potential. However, there is a lack of knowledge on provenance-specific survival under severe drought events and on how acclimation alters survival rates in Scots pine seedlings. We therefore conducted two drought-induced mortality experiments with potted Scots pine seedlings in a greenhouse. In the first experiment, 760 three-year-old seedlings from 12 different provenances of the south-western distribution range were subjected to the same treatment followed by the mortality experiment in 2014. In the second experiment, we addressed the question of whether acclimation to re-occurring drought stress events and to elevated temperature might decrease mortality rates. Thus, 139 four-year-old seedlings from France, Germany, and Poland were subjected to different temperature regimes (2012–2014) and drought treatments (2013–2014) before the mortality experiment in 2015. Provenances clearly differed in their hazard of drought-induced mortality, which was only partly related to the climate of their origin. Drought acclimation decreased the hazard of drought-induced mortality. Above-ground dry weight and height were the main determinants for the hazard of mortality, i.e., heavier and taller seedlings were more prone to mortality. Consequently, Scots pine seedlings exhibit a considerable provenance-specific acclimation potential against drought mortality and the selection of suitable provenances might thus facilitate seedling establishment and the persistence of Scots pine forest. PMID:27458477

  8. Risk Assessment of Genetically Engineered Maize Resistant to Diabrotica spp.: Influence on Above-Ground Arthropods in the Czech Republic.

    Zdeňka Svobodová

    Full Text Available Transgenic maize MON88017, expressing the Cry3Bb1 toxin from Bacillus thuringiensis (Bt maize, confers resistance to corn rootworms (Diabrotica spp. and provides tolerance to the herbicide glyphosate. However, prior to commercialization, substantial assessment of potential effects on non-target organisms within agroecosystems is required. The MON88017 event was therefore evaluated under field conditions in Southern Bohemia in 2009-2011, to detect possible impacts on the above-ground arthropod species. The study compared MON88017, its near-isogenic non-Bt hybrid DK315 (treated or not treated with the soil insecticide Dursban 10G and two non-Bt reference hybrids (KIPOUS and PR38N86. Each hybrid was grown on five 0.5 ha plots distributed in a 14-ha field with a Latin square design. Semiquantitative ELISA was used to verify Cry3Bb1 toxin levels in the Bt maize. The species spectrum of non-target invertebrates changed during seasons and was affected by weather conditions. The thrips Frankliniella occidentalis was the most abundant species in all three successive years. The next most common species were aphids Rhopalosiphum padi and Metopolophium dirhodum. Frequently observed predators included Orius spp. and several species within the Coccinellidae. Throughout the three-year study, analysis of variance indicated some significant differences (P<0.05. Multivariate analysis showed that the abundance and diversity of plant dwelling insects was similar in maize with the same genetic background, for both Bt (MON88017 and non-Bt (DK315 untreated or insecticide treated. KIPOUS and PR38N86 showed some differences in species abundance relative to the Bt maize and its near-isogenic hybrid. However, the effect of management regime on arthropod community was insignificant and accounted only for a negligible portion of the variability.

  9. Above-Ground Dimensions and Acclimation Explain Variation in Drought Mortality of Scots Pine Seedlings from Various Provenances.

    Seidel, Hannes; Menzel, Annette

    2016-01-01

    Seedling establishment is a critical part of the life cycle, thus seedling survival might be even more important for forest persistence under recent and future climate change. Scots pine forests have been disproportionally more affected by climate change triggered forest-dieback. Nevertheless, some Scots pine provenances might prove resilient to future drought events because of the species' large distributional range, genetic diversity, and adaptation potential. However, there is a lack of knowledge on provenance-specific survival under severe drought events and on how acclimation alters survival rates in Scots pine seedlings. We therefore conducted two drought-induced mortality experiments with potted Scots pine seedlings in a greenhouse. In the first experiment, 760 three-year-old seedlings from 12 different provenances of the south-western distribution range were subjected to the same treatment followed by the mortality experiment in 2014. In the second experiment, we addressed the question of whether acclimation to re-occurring drought stress events and to elevated temperature might decrease mortality rates. Thus, 139 four-year-old seedlings from France, Germany, and Poland were subjected to different temperature regimes (2012-2014) and drought treatments (2013-2014) before the mortality experiment in 2015. Provenances clearly differed in their hazard of drought-induced mortality, which was only partly related to the climate of their origin. Drought acclimation decreased the hazard of drought-induced mortality. Above-ground dry weight and height were the main determinants for the hazard of mortality, i.e., heavier and taller seedlings were more prone to mortality. Consequently, Scots pine seedlings exhibit a considerable provenance-specific acclimation potential against drought mortality and the selection of suitable provenances might thus facilitate seedling establishment and the persistence of Scots pine forest. PMID:27458477

  10. Detection of large above-ground biomass variability in lowland forest ecosystems by airborne LiDAR

    J. Jubanski

    2013-06-01

    Full Text Available Quantification of tropical forest above-ground biomass (AGB over large areas as input for Reduced Emissions from Deforestation and forest Degradation (REDD+ projects and climate change models is challenging. This is the first study which attempts to estimate AGB and its variability across large areas of tropical lowland forests in Central Kalimantan (Indonesia through correlating airborne light detection and ranging (LiDAR to forest inventory data. Two LiDAR height metrics were analysed, and regression models could be improved through the use of LiDAR point densities as input (R2 = 0.88; n = 52. Surveying with a LiDAR point density per square metre of about 4 resulted in the best cost / benefit ratio. We estimated AGB for 600 km of LiDAR tracks and showed that there exists a considerable variability of up to 140% within the same forest type due to varying environmental conditions. Impact from logging operations and the associated AGB losses dating back more than 10 yr could be assessed by LiDAR but not by multispectral satellite imagery. Comparison with a Landsat classification for a 1 million ha study area where AGB values were based on site-specific field inventory data, regional literature estimates, and default values by the Intergovernmental Panel on Climate Change (IPCC showed an overestimation of 43%, 102%, and 137%, respectively. The results show that AGB overestimation may lead to wrong greenhouse gas (GHG emission estimates due to deforestation in climate models. For REDD+ projects this leads to inaccurate carbon stock estimates and consequently to significantly wrong REDD+ based compensation payments.

  11. Risk Assessment of Genetically Engineered Maize Resistant to Diabrotica spp.: Influence on Above-Ground Arthropods in the Czech Republic.

    Svobodová, Zdeňka; Skoková Habuštová, Oxana; Hutchison, William D; Hussein, Hany M; Sehnal, František

    2015-01-01

    Transgenic maize MON88017, expressing the Cry3Bb1 toxin from Bacillus thuringiensis (Bt maize), confers resistance to corn rootworms (Diabrotica spp.) and provides tolerance to the herbicide glyphosate. However, prior to commercialization, substantial assessment of potential effects on non-target organisms within agroecosystems is required. The MON88017 event was therefore evaluated under field conditions in Southern Bohemia in 2009-2011, to detect possible impacts on the above-ground arthropod species. The study compared MON88017, its near-isogenic non-Bt hybrid DK315 (treated or not treated with the soil insecticide Dursban 10G) and two non-Bt reference hybrids (KIPOUS and PR38N86). Each hybrid was grown on five 0.5 ha plots distributed in a 14-ha field with a Latin square design. Semiquantitative ELISA was used to verify Cry3Bb1 toxin levels in the Bt maize. The species spectrum of non-target invertebrates changed during seasons and was affected by weather conditions. The thrips Frankliniella occidentalis was the most abundant species in all three successive years. The next most common species were aphids Rhopalosiphum padi and Metopolophium dirhodum. Frequently observed predators included Orius spp. and several species within the Coccinellidae. Throughout the three-year study, analysis of variance indicated some significant differences (Pinsects was similar in maize with the same genetic background, for both Bt (MON88017) and non-Bt (DK315) untreated or insecticide treated. KIPOUS and PR38N86 showed some differences in species abundance relative to the Bt maize and its near-isogenic hybrid. However, the effect of management regime on arthropod community was insignificant and accounted only for a negligible portion of the variability. PMID:26083254

  12. Interactive effects of frequent burning and timber harvesting on above ground carbon biomass in temperate eucalypt forests

    Collins, Luke; Penman, Trent; Ximenes, Fabiano; Bradstock, Ross

    2015-04-01

    The sequestration of carbon has been identified as an important strategy to mitigate the effects of climate change. Fuel reduction burning and timber harvesting are two common co-occurring management practices within forests. Frequent burning and timber harvesting may alter forest carbon pools through the removal and redistribution of biomass and demographic and structural changes to tree communities. Synergistic and antagonistic interactions between frequent burning and harvesting are likely to occur, adding further complexity to the management of forest carbon stocks. Research aimed at understanding the interactive effects of frequent fire and timber harvesting on carbon biomass is lacking. This study utilised data from two long term (25 - 30 years) manipulative burning experiments conducted in southern Australia in temperate eucalypt forests dominated by resprouting canopy species. Specifically we examined the effect of fire frequency and harvesting on (i) total biomass of above ground carbon pools and (ii) demographic and structural characteristics of live trees. We also investigated some of the mechanisms driving these changes. Frequent burning reduced carbon biomass by up to 20% in the live tree carbon pool. Significant interactions occurred between fire and harvesting, whereby the reduction in biomass of trees >20 cm diameter breast height (DBH) was amplified by increased fire frequency. The biomass of trees DBH increased with harvesting intensity in frequently burnt areas, but was unaffected by harvesting intensity in areas experiencing low fire frequency. Biomass of standing and fallen coarse woody debris was relatively unaffected by logging and fire frequency. Fire and harvesting significantly altered stand structure over the study period. Comparison of pre-treatment conditions to current conditions revealed that logged sites had a significantly greater increase in the number of small trees (DBH) than unlogged sites. Logged sites showed a significant

  13. Modelling above-ground carbon dynamics using multi-temporal airborne lidar: insights from a Mediterranean woodland

    Simonson, W.; Ruiz-Benito, P.; Valladares, F.; Coomes, D.

    2016-02-01

    Woodlands represent highly significant carbon sinks globally, though could lose this function under future climatic change. Effective large-scale monitoring of these woodlands has a critical role to play in mitigating for, and adapting to, climate change. Mediterranean woodlands have low carbon densities, but represent important global carbon stocks due to their extensiveness and are particularly vulnerable because the region is predicted to become much hotter and drier over the coming century. Airborne lidar is already recognized as an excellent approach for high-fidelity carbon mapping, but few studies have used multi-temporal lidar surveys to measure carbon fluxes in forests and none have worked with Mediterranean woodlands. We use a multi-temporal (5-year interval) airborne lidar data set for a region of central Spain to estimate above-ground biomass (AGB) and carbon dynamics in typical mixed broadleaved and/or coniferous Mediterranean woodlands. Field calibration of the lidar data enabled the generation of grid-based maps of AGB for 2006 and 2011, and the resulting AGB change was estimated. There was a close agreement between the lidar-based AGB growth estimate (1.22 Mg ha-1 yr-1) and those derived from two independent sources: the Spanish National Forest Inventory, and a tree-ring based analysis (1.19 and 1.13 Mg ha-1 yr-1, respectively). We parameterised a simple simulator of forest dynamics using the lidar carbon flux measurements, and used it to explore four scenarios of fire occurrence. Under undisturbed conditions (no fire) an accelerating accumulation of biomass and carbon is evident over the next 100 years with an average carbon sequestration rate of 1.95 Mg C ha-1 yr-1. This rate reduces by almost a third when fire probability is increased to 0.01 (fire return rate of 100 years), as has been predicted under climate change. Our work shows the power of multi-temporal lidar surveying to map woodland carbon fluxes and provide parameters for carbon

  14. Modelling above-ground carbon dynamics using multi-temporal airborne lidar: insights from a Mediterranean woodland

    W. Simonson

    2015-09-01

    Full Text Available Woodlands represent highly significant carbon sinks globally, though could lose this function under future climatic change. Effective large-scale monitoring of these woodlands has a critical role to play in mitigating for, and adapting to, climate change. Mediterranean woodlands have low carbon densities, but represent important global carbon stocks due to their extensiveness and are particularly vulnerable because the region is predicted to become much hotter and drier over the coming century. Airborne lidar is already recognized as an excellent approach for high-fidelity carbon mapping, but few studies have used multi-temporal lidar surveys to measure carbon fluxes in forests and none have worked with Mediterranean woodlands. We use a multi-temporal (five year interval airborne lidar dataset for a region of central Spain to estimate above-ground biomass (AGB and carbon dynamics in typical mixed broadleaved/coniferous Mediterranean woodlands. Field calibration of the lidar data enabled the generation of grid-based maps of AGB for 2006 and 2011, and the resulting AGB change were estimated. There was a close agreement between the lidar-based AGB growth estimate (1.22 Mg ha−1 year−1 and those derived from two independent sources: the Spanish National Forest Inventory, and a~tree-ring based analysis (1.19 and 1.13 Mg ha−1 year−1, respectively. We parameterised a simple simulator of forest dynamics using the lidar carbon flux measurements, and used it to explore four scenarios of fire occurrence. Under undisturbed conditions (no fire occurrence an accelerating accumulation of biomass and carbon is evident over the next 100 years with an average carbon sequestration rate of 1.95 Mg C ha−1 year−1. This rate reduces by almost a third when fire probability is increased to 0.01, as has been predicted under climate change. Our work shows the power of multi-temporal lidar surveying to map woodland carbon fluxes and provide parameters for carbon

  15. Importance of testing in nuclear facilities

    In nuclear facilities systems and materials important for safety and reliability are frequently tested. This paper analyzes testing during design, building and operation of nuclear facilities. Then different aspects of test quality are examined: requirements, test programming, test quality, interfaces. Mainly new facilities, pilots or prototypes are concerned

  16. Nuclear science of Kazakhstan and former nuclear test site

    This abstract contains short historical notes on the genesis of Kazakhstan nuclear science, on Semipalatinsk former test site, information on main directions of investigations in Kazakhstan National Nuclear Centre, on activity of the centre on non-proliferation problems

  17. EU-wide maps of growing stock and above-ground biomass in forests based on remote sensing and field measurements

    Gallaun, H.; Zanchi, G.; Nabuurs, G.J.; Hengeveld, G.M.; Schardt, M.; Verkerk, P.J.

    2010-01-01

    The overall objective of this study was to combine national forest inventory data and remotely sensed data to produce pan-European maps on growing stock and above-ground woody biomass for the two species groups " broadleaves" and " conifers" An automatic up-scaling approach making use of satellite r

  18. Above-ground biomass production and allometric relations of Eucalyptus globulus Labill. coppice plantations along a chronosequence in the central highlands of Ethiopia

    Eucalyptus plantations are extensively managed for wood production in the central highlands of Ethiopia. Nevertheless, little is known about their biomass (dry matter) production, partitioning and dynamics over time. Data from 10 different Eucalyptus globulus stands, with a plantation age ranging from 11 to 60 years and with a coppice-shoot age ranging from 1 to 9 years were collected and analyzed. Above-ground tree biomass of 7-10 sampled trees per stand was determined destructively. Dry weights of tree components (Wc; leaves, twigs, branches, stembark, and stemwood) and total above-ground biomass (Wa) were estimated as a function of diameter above stump (D), tree height (H) and a combination of these. The best fits were obtained, using combinations of D and H. When only one explanatory variable was used, D performed better than H. Total above-ground biomass was linearly related to coppice-shoot age. In contrast a negative relation was observed between the above-ground biomass production and total plantation age (number of cutting cycles). Total above-ground biomass increased from 11 t ha-1 at a stand age of 1 year to 153 t ha-1 at 9 years. The highest dry weight was allocated to stemwood and decreased in the following order: stemwood > leaves > stembark > twigs > branches. The equations developed in this study to estimate biomass components can be applied to other Eucalyptus plantations under the assumption that the populations being studied are similar with regard to density and tree size to those for which the relationships were developed

  19. Estimating the Above-Ground Biomass in Miombo Savanna Woodlands (Mozambique, East Africa Using L-Band Synthetic Aperture Radar Data

    Maria J. Vasconcelos

    2013-03-01

    Full Text Available The quantification of forest above-ground biomass (AGB is important for such broader applications as decision making, forest management, carbon (C stock change assessment and scientific applications, such as C cycle modeling. However, there is a great uncertainty related to the estimation of forest AGB, especially in the tropics. The main goal of this study was to test a combination of field data and Advanced Land Observing Satellite (ALOS Phased Array L-band Synthetic Aperture Radar (PALSAR backscatter intensity data to reduce the uncertainty in the estimation of forest AGB in the Miombo savanna woodlands of Mozambique (East Africa. A machine learning algorithm, based on bagging stochastic gradient boosting (BagSGB, was used to model forest AGB as a function of ALOS PALSAR Fine Beam Dual (FBD backscatter intensity metrics. The application of this method resulted in a coefficient of correlation (R between observed and predicted (10-fold cross-validation forest AGB values of 0.95 and a root mean square error of 5.03 Mg·ha−1. However, as a consequence of using bootstrap samples in combination with a cross validation procedure, some bias may have been introduced, and the reported cross validation statistics could be overoptimistic. Therefore and as a consequence of the BagSGB model, a measure of prediction variability (coefficient of variation on a pixel-by-pixel basis was also produced, with values ranging from 10 to 119% (mean = 25% across the study area. It provides additional and complementary information regarding the spatial distribution of the error resulting from the application of the fitted model to new observations.

  20. Ecological consequences of nuclear testing

    Many of the terrestrial disturbances on Amchitka Island resulting from nuclear testing were superimposed on scars remaining from military occupation. Construction, road improvement, and the Milrow and Cannikin nuclear detonations resulted in the loss or deterioration of about 420 ha (1040 acres) of terrestrial habitat, or less than 1.5% of the total area of Amchitka. A few streams and lakes were polluted by drilling effluents or human wastes; normal flushing action is expected to restore the quality of most of these freshwater habitats. Irreversible effects in freshwaters include the drainage of several ponds, gross channel alteration in a part of one stream, and the creation of a new lake which is deeper and which has a greater volume than any of the more than 2100 natural lakes on the southeast half of Amchitka. About 6 ha (15 acres) of intertidal bench was displaced to a level above the intertidal zone, and an undetermined amount of similar habitat was altered to some degree by lesser vertical displacement. No type of habitat on the island was destroyed, and localized habitat losses in the terrestrial, freshwater, and marine ecosystems are believed to have been too slight to have permanent effects on associated biotic populations

  1. Importance of tests in nuclear facilities

    In nuclear facilities, safety related systems and equipments are subject, along their whole service-life, to numerous tests. This paper analyses the role of tests in the successive stages of design, construction, exploitation of a nuclear facility. It examines several aspects of test quality control: definition of needs, test planning, intrinsic quality of each test, control of interfaces (test are both the end and the starting point of many actions concerned by quality) and the application

  2. Assinatura da deposição atmosférica de testes nucleares em sedimentos da costa brasileira (240+239Pu e 137Cs

    Christian J. Sanders

    2012-01-01

    Full Text Available The aim of this review is to take a look at Cold War era nuclear tests signatures found in Brazilian coastal sediments. Both137Cs and 240+239Pu signatures have been documented in mangrove, coastal mudflats and continental shelf sediments, associated with above ground nuclear tests beginning in the 1950's. The dates associated to the anthropogenic radionuclide signatures 137Cs and 240+239Pu along sediment columns are confirmed by 210Pb geochronology in many of the studies highlighted in this review. The results outlined in this review characterize the extent to which nuclear fallout products reach the Brazilian coast in quantities sufficient for detection, allowing the use of these radioisotopes as geochronometers.

  3. Diversity and above-ground biomass patterns of vascular flora induced by flooding in the drawdown area of China's Three Gorges Reservoir.

    Qiang Wang

    Full Text Available Hydrological alternation can dramatically influence riparian environments and shape riparian vegetation zonation. However, it was difficult to predict the status in the drawdown area of the Three Gorges Reservoir (TGR, because the hydrological regime created by the dam involves both short periods of summer flooding and long-term winter impoundment for half a year. In order to examine the effects of hydrological alternation on plant diversity and biomass in the drawdown area of TGR, twelve sites distributed along the length of the drawdown area of TGR were chosen to explore the lateral pattern of plant diversity and above-ground biomass at the ends of growing seasons in 2009 and 2010. We recorded 175 vascular plant species in 2009 and 127 in 2010, indicating that a significant loss of vascular flora in the drawdown area of TGR resulted from the new hydrological regimes. Cynodon dactylon and Cyperus rotundus had high tolerance to short periods of summer flooding and long-term winter flooding. Almost half of the remnant species were annuals. Species richness, Shannon-Wiener Index and above-ground biomass of vegetation exhibited an increasing pattern along the elevation gradient, being greater at higher elevations subjected to lower submergence stress. Plant diversity, above-ground biomass and species distribution were significantly influenced by the duration of submergence relative to elevation in both summer and previous winter. Several million tonnes of vegetation would be accumulated on the drawdown area of TGR in every summer and some adverse environmental problems may be introduced when it was submerged in winter. We conclude that vascular flora biodiversity in the drawdown area of TGR has dramatically declined after the impoundment to full capacity. The new hydrological condition, characterized by long-term winter flooding and short periods of summer flooding, determined vegetation biodiversity and above-ground biomass patterns along the

  4. Estimating above-ground biomass by fusion of LiDAR and multispectral data in subtropical woody plant communities in topographically complex terrain in North-eastern Australia

    Sisira Ediriweera; Sumith Pathirana; Tim Danaher; Doland Nichols

    2014-01-01

    We investigated a strategy to improve predicting capacity of plot-scale above-ground biomass (AGB) by fusion of LiDAR and Land-sat5 TM derived biophysical variables for subtropical rainforest and eucalypts dominated forest in topographically complex landscapes in North-eastern Australia. Investigation was carried out in two study areas separately and in combination. From each plot of both study areas, LiDAR derived structural parameters of vegetation and reflectance of all Landsat bands, vegetation indices were employed. The regression analysis was carried out separately for LiDAR and Landsat derived variables indi-vidually and in combination. Strong relationships were found with LiDAR alone for eucalypts dominated forest and combined sites compared to the accuracy of AGB estimates by Landsat data. Fusing LiDAR with Landsat5 TM derived variables increased overall performance for the eucalypt forest and combined sites data by describing extra variation (3% for eucalypt forest and 2% combined sites) of field estimated plot-scale above-ground biomass. In contrast, separate LiDAR and imagery data, and fusion of LiDAR and Landsat data performed poorly across structurally complex closed canopy subtropical rainforest. These findings reinforced that obtaining accurate estimates of above ground biomass using remotely sensed data is a function of the complexity of horizontal and vertical structural diversity of vegetation.

  5. Above-ground tree outside forest (TOF) phytomass and carbon estimation in the semiarid region of southern Haryana: A synthesis approach of remote sensing and field data

    Kuldeep Singh; Pritam Chand

    2012-12-01

    Trees outside forest (TOF) play an important role in global carbon cycling, since they are large pools of carbon as well as potential carbon sinks and sources to the atmosphere. In view of the importance of biomass estimates in the global carbon (C) cycle, the present study demonstrates the potential of the standwise tree outside forest inventory data and finer spatial resolution of IRS-P6 LISS-IV satellite data to classify TOF, to estimate above-ground TOF phytomass and the carbon content of TOF in a semiarid region of the southern Haryana, India. The study reports that above-ground TOF phytomass varied from 1.26 tons/ha in the scattered trees in the rural/urban area to 91.5 tons/ha in the dense linear TOF along the canal. The total above-ground TOF phytomass and carbon content was calculated as 367.04 and 174.34 tons/ha, respectively in the study area. The study results conclude that the classification of TOF and estimation of phytomass and carbon content in TOF can be successfully achieved through the combined approach of Remote Sensing and GIS based spatial technique with the supplement of field data. The present approach will help to find out the potential carbon sequestration zone in the semi-arid region of southern Haryana, India.

  6. Political aspects of nuclear test effects at Semipalatinsk nuclear test site

    The paper describes tense struggle of Kazakhstan people for closure of the Semipalatinsk Nuclear Test Site. It reveals major foreign policy aspects and nuclear test effects for both Kazakhstan and the world community. (author)

  7. Estimation of the carbon pool in soil and above-ground biomass within mangrove forests in Southeast Mexico using allometric equations

    Jesús Jaime Guerra-Santos; Rosa María Cerón-Bretón; Julia Griselda Cerón-Bretón; Diana Lizett Damián-Hernández; Reyna Cristina Sánchez-Junco; Emma del Carmen Guevara Carrió

    2014-01-01

    We report the results of carbon stored in soil and aboveground biomass from the most important area of mangroves in Mexico, with dominant vegetation of Red mangrove (Rhizophora mangle L.), Black mangrove (Avicennia germinans L.), white mangrove (Laguncularia racemosa Gaertn.) and button mangrove (Conocarpus erectus L.). We sampled soils with high fertility during the dry season in 2009 and 2010 at three sites on Atasta Peninsula, Campeche. We used allometric equations to estimate above ground biomass (AGB) of trees. AGB was higher in C. erectus (253.18±32.17 t⋅ha-1), lower in A. germinans (161.93±12.63 t⋅ha-1), and intermediate in R. mangle (181.70±16.58 t⋅ha-1) and L. racemosa (206.07±19.12 t⋅ha-1). Of the three studied sites, the highest absolute value for AGB was 279.72 t⋅ha-1 in button mangrove forest at any single site. Carbon stored in soil at the three sites ranged from 36.80±10.27 to 235.77±66.11 t⋅ha-1. The Tukey test (p <0.05) made for AGB was higher for black mangrove showed significant differences in soil carbon content between black mangrove and button mangrove. C. erectus had higher AGB compared with the other species. A. germinans trees had lower AGB because they grew in hypersaline environments, which reduced their development. C. erectus grew on higher ground where soils were richer in nutrients. AGB tended to be low in areas near the sea and increased with distance from the coast. A. germinans usually grew on recently deposited sediments. We assumed that all sites have the same potential to store carbon in soil, and then we found that there were no significant differences in carbon content between the three samples sites: all sites had potential to store carbon for long periods. Carbon storage at the three sampling sites in the state of Campeche, Mexico, was higher than that reported for other locations.

  8. Ground test facility for nuclear testing of space reactor subsystems

    Two major reactor facilities at the INEL have been identified as easily adaptable for supporting the nuclear testing of the SP-100 reactor subsystem. They are the Engineering Test Reactor (ETR) and the Loss of Fluid Test Reactor (LOFT). In addition, there are machine shops, analytical laboratories, hot cells, and the supporting services (fire protection, safety, security, medical, waste management, etc.) necessary to conducting a nuclear test program. This paper presents the conceptual approach for modifying these reactor facilities for the ground engineering test facility for the SP-100 nuclear subsystem. 4 figs

  9. Nuclear: Water-testing time?

    With Florida Power and Light Co reporting that five unnamed independent power producers specified nuclear powerplants in response to the utility's Request for Proposal for 800 MW (EW, January 1990, p 15), along with a report in McGraw-Hill's Nucleonics Week that Florida Public Service Commission (PSC) Chairman Michael Wilson told Westinghouse Electric Corp - developer of the AP-600 reactor - he did not have a knee-jerk reaction against nuclear power if it's done right, speculation increases that the state of Florida is one of the top locations in the US for the next nuclear order

  10. The Comprehensive Nuclear Test Ban Treaty

    The Comprehensive Nuclear-Test-Ban Treaty (CTBT) is a cornerstone of the international regime on the non-proliferation of nuclear weapons and an essential foundation for the pursuit of nuclear disarmament. Its total ban of any nuclear weapon test explosion will constrain the development and qualitative improvement of nuclear weapons and end the development of advanced new types of these weapons. The Comprehensive Nuclear-Test-Ban Treaty was adopted by the United Nations General Assembly, and was opened for signature in New York on 24 September 1996. The Treaty will enter into force after it has been ratified by the 44 States listed in its Annex 2. These states possess nuclear power or research reactors. The Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO Preparatory Commission) is an international organization established by the States Signatories to the Treaty on 19 November 1996. It carries out the necessary preparations for the effective implementation of the Treaty, and prepares for the first session of the Conference of the States Parties to the Treaty. The Treaty has been signed and ratified by the Republic of Croatia and National Commission for the implementation of the Treaty has been established. Basic obligations of the Treaty, as specified in Article I, are: (1) Each State Party undertakes not to carry out any nuclear weapon test explosion or any other nuclear explosion, and to prohibit and prevent any such nuclear explosion at any place under its jurisdiction or control. (2) Each State Party undertakes, furthermore, to refrain from causing, encouraging, or in any way participating in the carrying out of any nuclear weapon test explosion or any other nuclear explosion.(author)

  11. Comprehensive Nuclear Test-ban Treaty

    The Comprehensive Nuclear Test-Ban Treaty was adopted by the General Assembly on 10 September 1996 (Res/50/245) and was open for signature by all states on 24 September 1996. It will enter into force 180 days after the date of deposit of the instruments of ratification by all states listed in Annex 2 to the Treaty. This document reproduces the text of the Treaty and the Protocol to the Comprehensive Nuclear Test-Ban Treaty Protocol to the Comprehensive Nuclear Test-Ban Treaty

  12. Impacts of Woody Invader Dillenia suffruticosa (Griff. Martelli on Physio-chemical Properties of Soil and, Below and Above Ground Flora

    B.A.K. Wickramathilake

    2014-01-01

    Full Text Available Dillenia suffruticosa (Griffith Martelli, that spreads fast in low-lying areas in wet zone of Sri Lanka is currently listed as a nationally important Invasive Alien Species that deserves attention in ecological studies. Thus, impact of this woody invader on physical, chemical properties of soil and below and above ground flora was investigated. Five sampling sites were identified along a distance of 46km from Avissawella to Ratnapura. At each site, two adjacent plots [1m x10m each for D. suffruticosa present (D+ and absent (D-] were outlined. Physical and chemical soil parameters, microbial biomass and number of bacterial colonies in soil were determined using standard procedures and compared between D+ and D- by ANOVA using SPSS. Rate of decomposition of D. suffruticosa leaves was also determined using the litter bag technique at 35% and 50% moisture levels. Above ground plant species richness in sample stands was compared using Jaccard and Sorenson diversity indices.  Decomposition of D. suffruticosa leaves was slow, but occurred at a more or less similar rate irrespective of moisture content of soil. Particle size distribution in D+ soil showed a much higher percentage of large soil particles.  Higher % porosity in D+ sites was a clear indication that the soil was aerated.  The pH was significantly lower for D+ than D- thus developing acidic soils whereas conductivity has been significantly high making soil further stressed. The significant drop in Cation Exchange Capacity (CEC in D+ soil was a remarkable finding to be concerned with as it correlated with fertility of soil. Significantly higher values of phosphates reported in D+ soil support the idea that plant invaders are capable to increase phosphates in soil. Higher biomass values recorded for D+ sites together with higher number of bacterial colonies could be related to the unexpectedly recorded higher Organic Carbon. Both  the  Jaccard  and  Sorenson   indices indicated  that

  13. Soviet nuclear testing: The Republics say no

    Massive protests are taking place in Russia against nuclear weapons testing. Efforts have been mounted to stop all testing at Kazakhstan test site near the town of Semipalatinsk, site of the first nuclear detonation in 1949 and of more than 500 test conducted since. Boris Yeltsin proposed just after his election as president of the federation the elimination of testing grounds for nuclear and biological weapons on Russian territory. The central government in Moscow has announced that it is considering closing the Semipalatinsk site. Reaction has also been strong to testing at the Arctic island of Novaya Zemlya, and severe constraints, such as Arctic cold, frozen rocks, high winds, difficult access, and protests by Greenpeace activists and USSR's Nordic neighbors do not make this site attractive. The author feels that this movement in the USSR has set in motion a politically dynamic situation that makes for the best chance for a comprehensive test ban treaty yet witnessed

  14. Trustworthiness test of nuclear power station employees

    The trustworthiness test is an important part of securing nuclear facilities against internal offenders. For performing such a test the supervisory authority, which is the State's physical protection authority, contacts the security offices or authorities regarding persons who work inside the sensitive areas of nuclear power stations - areas containing nuclear material. The trustworthiness test covers the present activities of the employees and gives a prediction for the following five years; after this time the test must be repeated. The trustworthiness test is a prerequisite for a facility to obtain a licence for the use of nuclear material, to hire persons for work in the inner area of a nuclear facility or the hire persons for leading positions. In Germany the content and form of the test as well as the evaluation of the results are regulated in a guideline of the Federal Ministry for the Environment, Nature Conservation and Reactor Safety (BMU) (latest edition in June 1996). The test is performed by the licensing authority or the supervisory authority. the basis of the test is a declaration by the employee concerned, containing personal data and the agreement of the person to the use of the data files by the safety authorities. It the results of the test are positive, the person tested has the possibility to comment on differences or to explain certain facts. The paper presents details of the BMU guideline. (author)

  15. On the hydrostatic test for nuclear vessels

    A comparison of the pressure test requirements, namely specified values of pressure and temperature, for nuclear vessels designed and constructed according to the ASME Code and Spanish Rules is presented. Also the relationship of the design criteria and the pressure test requirements is indicated with a particular emphasis on the test temperature in order to avoid brittle behaviour of the materials. (author)

  16. Effect of Polythene-covering on Above-ground tuberization and storage roots yield in Cassava (Manihot esculenta Crantz

    Abdullahi N

    2014-02-01

    Full Text Available Present study aimed to investigate the effectiveness of polythene-covering on activation of dormant auxiliary buds on the stem for lateral tuber formation and the resultant effect on total storage roots yield. Three time intervals i.e. 1 day after planting, 30 days after planting and 60 days after planting used as treatment, and uncovered stem used as control. Treatments were tested in randomized complete block design with three replications. Regardless of the variety, stem polythene-covering at day 1 after planting showed the highest effect with respect to storage roots production and yield components tested. However, the effect of stem polythene-covering at day 1 after planting in terms of dry mass partitioning to storage roots was the lowest across all the treatments (25.50 to 27.37% of the biomass compared to that of stem covering at day 60 after planting (33.10 to 37.20%. This study opens new perspectives in cassava yield improvement which hitherto has not been exploited.

  17. Above-ground woody carbon sequestration measured from tree rings is coherent with net ecosystem productivity at five eddy-covariance sites.

    Babst, Flurin; Bouriaud, Olivier; Papale, Dario; Gielen, Bert; Janssens, Ivan A; Nikinmaa, Eero; Ibrom, Andreas; Wu, Jian; Bernhofer, Christian; Köstner, Barbara; Grünwald, Thomas; Seufert, Günther; Ciais, Philippe; Frank, David

    2014-03-01

    • Attempts to combine biometric and eddy-covariance (EC) quantifications of carbon allocation to different storage pools in forests have been inconsistent and variably successful in the past. • We assessed above-ground biomass changes at five long-term EC forest stations based on tree-ring width and wood density measurements, together with multiple allometric models. Measurements were validated with site-specific biomass estimates and compared with the sum of monthly CO₂ fluxes between 1997 and 2009. • Biometric measurements and seasonal net ecosystem productivity (NEP) proved largely compatible and suggested that carbon sequestered between January and July is mainly used for volume increase, whereas that taken up between August and September supports a combination of cell wall thickening and storage. The inter-annual variability in above-ground woody carbon uptake was significantly linked with wood production at the sites, ranging between 110 and 370 g C m(-2) yr(-1) , thereby accounting for 10-25% of gross primary productivity (GPP), 15-32% of terrestrial ecosystem respiration (TER) and 25-80% of NEP. • The observed seasonal partitioning of carbon used to support different wood formation processes refines our knowledge on the dynamics and magnitude of carbon allocation in forests across the major European climatic zones. It may thus contribute, for example, to improved vegetation model parameterization and provides an enhanced framework to link tree-ring parameters with EC measurements. PMID:24206564

  18. Nuclear Fuel Test Rod Fabrication for Data Acquisition Test

    A nuclear fuel test rod must be fabricated with precise welding and assembly technologies, and confirmed for their soundness. Recently, we have developed various kinds of processing systems such as an orbital TIG welding system, a fiber laser welding system, an automated drilling system and a helium leak analyzer, which are able to fabricate the nuclear fuel test rods and rigs, and keep inspection systems to confirm the soundness of the nuclear fuel test rods and rids. The orbital TIG welding system can be used with two kinds of welding methods. One can perform the round welding for end-caps of a nuclear fuel test rod by an orbital head mounted in a low-pressure chamber. The other can do spot welding for a pin-hole of a nuclear fuel test rod in a high-pressure chamber to fill up helium gas of high pressure. The fiber laser welding system can weld cylindrical and 3 axis samples such as parts of a nuclear fuel test rod and instrumentation sensors which is moved by an index chuck and a 3 axis (X, Y, Z) servo stage controlled by the CNC program. To measure the real-time temperature change at the center of the nuclear fuel during the irradiation test, a thermocouple should be instrumented at that position. Therefore, a hole needs to be made at the center of fuel pellet to instrument the thermocouple. An automated drilling system can drill a fine hole into a fuel pellet without changing tools or breaking the work-piece. The helium leak analyzer (ASM-380 model of DEIXEN Co.) can check the leak of the nuclear fuel test rod filled with helium gas. This paper describes not only the assembly and fabrication methods used by the process systems, but also the results of the data acquisition test for the nuclear fuel test rod. A nuclear fuel test rod for the data acquisition test was fabricated using the welding and assembling echnologies acquired from previous tests

  19. Nuclear Fuel Test Rod Fabrication for Data Acquisition Test

    Joung, Chang-Young; Hong, Jin-Tae; Kim, Ka-Hye; Huh, Sung-Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    A nuclear fuel test rod must be fabricated with precise welding and assembly technologies, and confirmed for their soundness. Recently, we have developed various kinds of processing systems such as an orbital TIG welding system, a fiber laser welding system, an automated drilling system and a helium leak analyzer, which are able to fabricate the nuclear fuel test rods and rigs, and keep inspection systems to confirm the soundness of the nuclear fuel test rods and rids. The orbital TIG welding system can be used with two kinds of welding methods. One can perform the round welding for end-caps of a nuclear fuel test rod by an orbital head mounted in a low-pressure chamber. The other can do spot welding for a pin-hole of a nuclear fuel test rod in a high-pressure chamber to fill up helium gas of high pressure. The fiber laser welding system can weld cylindrical and 3 axis samples such as parts of a nuclear fuel test rod and instrumentation sensors which is moved by an index chuck and a 3 axis (X, Y, Z) servo stage controlled by the CNC program. To measure the real-time temperature change at the center of the nuclear fuel during the irradiation test, a thermocouple should be instrumented at that position. Therefore, a hole needs to be made at the center of fuel pellet to instrument the thermocouple. An automated drilling system can drill a fine hole into a fuel pellet without changing tools or breaking the work-piece. The helium leak analyzer (ASM-380 model of DEIXEN Co.) can check the leak of the nuclear fuel test rod filled with helium gas. This paper describes not only the assembly and fabrication methods used by the process systems, but also the results of the data acquisition test for the nuclear fuel test rod. A nuclear fuel test rod for the data acquisition test was fabricated using the welding and assembling echnologies acquired from previous tests.

  20. Using multi-frequency radar and discrete-return LiDAR measurements to estimate above-ground biomass and biomass components in a coastal temperate forest

    Tsui, Olivier W.; Coops, Nicholas C.; Wulder, Michael A.; Marshall, Peter L.; McCardle, Adrian

    2012-04-01

    Height measurements from small-footprint discrete-return LiDAR and backscatter coefficients from C- and L-band radar were used independently and in combination to estimate above-ground component and total biomass for a coniferous temperate forest, located on Vancouver Island, British Columbia, Canada. Reference biomass data were obtained from plot-level data and used for comparison against the LiDAR and radar-based biomass models. For the LiDAR-only model, height metrics such as mean first return height and percentiles (e.g., 10th and 90th) of first returns correlated best to total above-ground and stem biomass. While percent of first returns above 2 m and percentiles (75th and 90th) of first returns height metrics correlated best to crown biomass. A comparison between above-ground components and total biomass indicate that stem biomass displayed the highest relationship with the LiDAR measurements while crown biomass showed the lowest relationship with relative root mean squared error ranging from 16% to 22%, respectively. Alternatively, the radar-only models indicated that for C-band radar, a combination of HH and VV backscatter demonstrated the most significant correlation with forest biomass compared to coherence based models with a relative root mean squared error of 53%. For L-band radar, a combination of HH and HV backscatter showed the most significant correlation compared to coherence based models with a relative root mean squared error of 44%. Exploring a mixture of C- and L-band backscatter and coherence based models revealed that a combination of C-HV and L-HV coherence magnitudes provided the best radar relationship with forest biomass with a relative root mean squared error of 35%. Also for all radar-based models, L- and C-band backscatter and coherence magnitudes were poorly correlated with individual biomass components when compared to total above-ground biomass. The addition of C- and L-band backscatter and coherence variables to the Li

  1. Estimation of Above-Ground Tree Biomass Based on Probability Distribution of Allometric Parameters%基于异速参数概率分布的立木地上生物量估算

    黄兴召; 陈东升; 孙晓梅; 张守攻

    2014-01-01

    Allometric biomass equations are widely used to predict above-ground biomass in forest ecosystems. It found the distribution of the parameters a and b of the allometry between above-ground biomass ( M ) and diameter at breast height( D) ,lnM = a + blnD,well approximated by a bivariate normal from analysis a data of 304 functions of 80 papers. ANOVA was tested to parameters in seven genera. In contrast to the parameter a,there was significant difference in parameter b. There were negative correlation between the parameter a and b,the parameter b and latitude. From this negative correlation,simultaneous-equation was used to build general model for parameters which were changed by latitude . Three methods which include established general model,minimum-least-square regression and Bayesian approach were used to fitting the above-ground biomass of Larix kaempferi in sub-tropical alpine area. The result showed that general model was the lowest precise quantifications ( R2 =0. 892 ) ,but it could estimate the biomass where forest situated in latitude without samples. With sample size was more than 50,both Bayesian method and minimum-least-square regression was no significant difference in the mean absolute error. And it was less than 50,Bayesian method was better than minimum-least-square regression. Therefore,it was suggested that Bayesian method was used to estimate above-ground biomass when the sample size was less than 50 .%对收集的80篇文献中304个地上部分生物量( M)和胸径( D)的异速生物量模型 lnM =a+blnD数据集研究发现:模型参数a和b符合二元正态分布;参数a和b之间、参数b和纬度间呈负相关,并依此相关关系应用联立方程组建立参数a和b随纬度变化的通用模型。以实测的北亚热带高山区日本落叶松地上部分生物量数据对新建的通用模型、最小二乘法和贝叶斯方法拟合生物量的适用性进行研究,结果表明:虽然通用模型的拟合精度最低( R

  2. Net Changes in Above Ground Woody Carbon Stock in Western Juniper Woodlands using Wavelet Techniques and Multi-temporal Aerial Photography

    Strand, E. K.; Bunting, S. C.; Smith, A. M.

    2006-12-01

    Expansion of woody plant cover in semi-arid ecosystems previously occupied primarily by grasses and forbs has been identified as an important land cover change process affecting the global carbon budget. Although woody encroachment occurs worldwide, quantifying changes in carbon pools and fluxes related to this phenomenon via remote sensing is challenging because large areas are affected at a fine spatial resolution (1- 10 m) and, in many cases, at slow temporal rates. Two-dimensional spatial wavelet analysis (SWA) represents a novel image processing technique that has been successful in automatically and objectively quantifying ecologically relevant features at multiple scales. We apply SWA to current and historic 1-m resolution black and white aerial photography to quantify changes in above ground woody biomass and carbon stock of western juniper (Juniperus occidentalis subsp. occidentalis) expanding into sagebrush (Artemisia spp.) steppe on the Owyhee Plateau in southwestern Idaho. Due to the large land area (330,000 ha) and variable availability of historical photography, we sampled forty-eight 100-ha blocks situated across the area, stratified using topographic, soil, and land stewardship variables. The average juniper plant cover increased one-fold (from 5.3% to 10.4% total cover) at the site during the time period of 1939-1946 to 1998-2004. Juniper plant density has increased by 128% with a higher percentage of the plant population in the smaller size classes compared to the size distribution 60 years ago. After image-based SWA delineation of tree crown sizes, we computed the change in above ground woody plant biomass and carbon stock between the two time periods using allometry. Areas where the shrub steppe is dominated by low sagebrush (Artemisia arbuscula) has experienced little to no expansion of western juniper. However, on deeper, more well drained soils capable of supporting mountain big sagebrush (Artemisia tridentata subsp. vaseyana), the above

  3. Euthanasia: above ground, below ground.

    Magnusson, R S

    2004-10-01

    The key to the euthanasia debate lies in how best to regulate what doctors do. Opponents of euthanasia frequently warn of the possible negative consequences of legalising physician assisted suicide and active euthanasia (PAS/AE) while ignoring the covert practice of PAS/AE by doctors and other health professionals. Against the background of survey studies suggesting that anything from 4% to 10% of doctors have intentionally assisted a patient to die, and interview evidence of the unregulated, idiosyncratic nature of underground PAS/AE, this paper assesses three alternatives to the current policy of prohibition. It argues that although legalisation may never succeed in making euthanasia perfectly safe, legalising PAS/AE may nevertheless be safer, and therefore a preferable policy alternative, to prohibition. At a minimum, debate about harm minimisation and the regulation of euthanasia needs to take account of PAS/AE wherever it is practised, both above and below ground. PMID:15467073

  4. A comprehensive ban on nuclear testing.

    Neild, R; Ruina, J P

    1972-01-14

    Our foregoing analysis of the role of a comprehensive test ban leads us to the following conclusions. 1) A CTB by itself will have little direct effect on the arms race between the superpowers. It would not hinder their nuclear arms production and deployment nor would it necessarily present a significant obstacle to the development of new nuclear weapons systems, despite limiting the development of new nuclear warhead designs. It can hardly make a dent in the destructive capability of the superpowers or in their ability to step up the pace of the arms race. 2) The chief merits of a CTB reside in the political sphere. It would help promote detente and could help to escalate interest in arms control agreements of broader scope. But in neither of these effects would it be as significant as a successful SALT (strategic arms limitation talks) agreement. The CTB also lingers as a piece of unfinished business since the signing of the LTB in 1963. The question can be and has been raised, "If the superpowers are serious about arms control, why have they not accepted the CTB, which is simple in concept and in form and is also free of serious military risks?" Such doubts about the sincerity of the superpowers' willingness to limit their own arms development will persist as long as there is no CTB. Substantial agreement at SALT would lessen some of this effect too, but would not eliminate it completely. 3) Recent progress in seismic identification has been impressive, and other means of obtaining technical intelligence about nuclear testing have probably also improved greatly. In addition, research on the technical means of on-site inspection has demonstrated its limited effectiveness. Therefore, the role of on-site inspections as an added deterrent to cheating on a CTB has diminished substantially. This is not to say that detection and identification of all nuclear tests is possible now, or ever, but only that on-site inspection would add very little to the other technical

  5. Correlation testing for nuclear density functional theory

    Correlation testing provides a quick method of discriminating amongst potential terms to include in a nuclear mass formula or functional and is a necessary tool for further nuclear mass models; however a firm mathematical foundation of the method has not been previously set forth. Here, the necessary justification for correlation testing is developed and more detail of the motivation behind its use is given. Examples are provided to clarify the method analytically and for computational benchmarking. We provide a quantitative demonstration of the method's performance and short-comings, highlighting also potential issues a user may encounter. In concluding we suggest some possible future developments to improve the limitations of the method. (orig.)

  6. Non-Nuclear Testing of Space Nuclear Systems at NASA MSFC

    Houts, Michael G.; Pearson, Boise J.; Aschenbrenner, Kenneth C.; Bradley, David E.; Dickens, Ricky; Emrich, William J.; Garber, Anne; Godfroy, Thomas J.; Harper, Roger T.; Martin, Jim J.; Polzin, Kurt; Schoenfeld, Michael P.; Webster, Kenneth L.

    2010-01-01

    Highly realistic non-nuclear testing can be used to investigate and resolve potential issues with space nuclear power and propulsion systems. Non-nuclear testing is particularly useful for systems designed with fuels and materials operating within their demonstrated nuclear performance envelope. Non-nuclear testing allows thermal hydraulic, heat transfer, structural, integration, safety, operational, performance, and other potential issues to be investigated and resolved with a greater degree of flexibility and at reduced cost and schedule compared to nuclear testing. The primary limit of non-nuclear testing is that nuclear characteristics and potential nuclear issues cannot be directly investigated. However, non-nuclear testing can be used to augment the potential benefit from any nuclear testing that may be required for space nuclear system design and development. This paper describes previous and ongoing non-nuclear testing related to space nuclear systems at NASA's Marshall Space Flight Center (MSFC).

  7. Residues from nuclear testing at the test site Azgir

    The Azgir test site is situated in the western part of the Republic of Kazakhstan, about 180 km north of the Caspian Sea. The Azgir test site was used for conducting peaceful nuclear explosions from 1966 to 1979. 17 underground tests were carried out in 10 wells which created 9 special cavities in the salt with depths from 160 to 1500 m. The total volume of these cavities is about 1,000,000 cubic meter. Resulting from this activity, there is an environmental contamination that may have affected population living in the adjacent areas. The results of investigations of radiological conditions that were performed after the closing of the Azgir test site, and current activities of international and Kazakhstan's institutions for studying residues from nuclear tests are also discussed in this report. (author)

  8. Studies of Health Effects from Nuclear Testing near the Semipalatinsk Nuclear Test Site, Kazakhstan

    Bernd Grosche; Tamara Zhunussova; Kazbek Apsalikov; Ausrele Kesminiene

    2015-01-01

    The nuclear bomb testing conducted at the Semipalatinsk nuclear test site in Kazakhstan is of great importance for today’s radiation protection research, particularly in the area of low dose exposures. This type of radiation is of particular interest due to the lack of research in this field and how it impacts population health. In order to understand the possible health effects of nuclear bomb testing, it is important to determine what studies have been conducted on the effects of low dose e...

  9. Risk Perception of Radiation Exposure of Villagers Living Near the Semipalatinsk Nuclear Test Site

    Purvis-Roberts, K. L.

    2006-12-01

    Connecting scientific data to societal needs is particularly important with the complex environmental issues that face us in the near future, such as global warming and natural hazards. Once the scientific data is collected and analyzed, dissemination of the results needs to be communicated to the public in a way that can be easily understood without glossing over the complexity of the issue. An interesting case study derives from the primary nuclear test site for the former Soviet Union, located near the city of Semipalatinsk, Kazakhstan. Villagers living directly adjacent to the Semipalatinsk Nuclear Test Site (SNTS) were exposed continuously to radioactive clouds from atmospheric, above ground and underground nuclear tests. The people living in the region are still exposed to low levels of radiation through the environmental contamination of their food and water and have experienced a higher incidence of cancers and birth defects than people living in other regions of the country. A database of historical environmental data was collected throughout the nuclear testing period by the Soviet government, tracking radiation concentrations through food, water, and soil samples around the SNTS, but this environmental data was never shared with the villagers. In fact, only after the Soviet Union fell apart in 1989 did the people discover that they had been exposed to radiation during the past 40 years. Through preliminary interviews with villagers, physicians, and scientists who live near the SNTS, it was discovered that the three groups viewed the risk of radiation exposure very differently. By developing a risk perception survey to understand how the different groups perceived radiation risk, and then comparing the scientific data to the survey results, a better way to communicate the risk could be developed. The risk perception survey was given to over 800 people in East Kazakhstan Oblast, including villagers living near the SNTS, scientists who study the

  10. Nuclear cask testing films misleading and misused

    In 1977 and 1978, Sandia National Laboratories, located in Albuquerque, New Mexico, and operated for the US Department of Energy (DOE), filmed a series of crash and fire tests performed on three casks designed to transport irradiated nuclear fuel assemblies. While the tests were performed to assess the applicability of scale and computer modeling techniques to actual accidents, films of them were quickly pressed into service by the DOE and nuclear utilities as ''proof'' to the public of the safety of the casks. In the public debate over the safety of irradiated nuclear fuel transportation, the films have served as the mainstay for the nuclear industry. Although the scripts of all the films were reviewed by USDOE officials before production, they contain numerous misleading concepts and images, and omit significant facts. The shorter versions eliminated qualifying statements contained in the longer version, and created false impressions. This paper discusses factors which cast doubt on the veracity of the films and the results of the tests

  11. Radiological criteria for underground nuclear tests

    The radiological criteria for the conduct of nuclear tests have undergone many revisions with the current criteria being 0.17 rad for uncontrolled populations and 0.5 rad for controllable populations. Their effect upon operations at the Nevada Test Site and the current off-site protective plans are reviewed for areas surrounding the Site. The few accidental releases that have occurred are used to establish estimates of probability of release and of hazard to the population. These are then put into context by comparing statistical data on other accidents and cataclysms. The guidelines established by DOE Manual Chapter MC-0524 have never been exceeded during the entire underground nuclear test program. The probability of real hazard to off-site populations appears to be sufficiently low as not to cause undue concern to the citizenry

  12. Nuclear weapon testing and the monkey business

    Reasons for India's total ban on the export of rhesus monkeys to U.S. have been explained. The major reason is that some of the animals were used in nuclear weapon related radiation experiments. This was a clear violation of a stricture in the agreement about supply of monkeys. The stricture prohibited the use of animals for research concerning military operations, including nuclear weapon testing. It is pleaded that a strict enforcement of strictures rather than a total ban on the export of monkeys would be better in the interest of advancement of knowledge in human medicine and disease control. (M.G.B.)

  13. Aseismic design and testing of nuclear facilities

    Earthquake possibility is a main problem faced by certain countries concerning nuclear reactor siting and safety. To assist in finding solutions to earthquake problems, a Panel on Aseismic Design and Testing of Nuclear Facilities was held from 12 to 16 June 1967 in Tokyo. Paper presented in the Panel are condensed into recommendations that comprise this report. Topics discussed in this report are (i) basic philosophy of aseismic design (ii) site selection or evaluation (iii) aseismic design and (iv) future action including investigations and research problems. Tabs

  14. Peculiarities of vegetation restoration of low mountain massif 'Degelen' of Semipalatinsk Test Sites after nuclear tests

    Full text: Geo-botanical researches in low mountain massif 'Degelen' Semipalatinsk Test Site were conducted out in 1994-2000 in the frames of INTAS 93-1422 and INTAS 96-2072 projects. 209 underground nuclear explosions were conducted out in horizontal adits in granite low mountain massif in 1968-1989. At present PED γ-irradiation reaches 100-500 μR/h in 14 adits, 500-1000 μR/h - in 8 adits, 1000-5000 μR/h - in 5 adits. Crests of the main mountain ridges and their lateral spurs were destroyed by multiple influence of blasts of nuclear explosions. 'Zones of split' appeared at the tops of the mountain ridges. Technogene screens appeared on the slopes of the mountain ridges. Radioactive springs appeared as a result of opening of water-bearing horizons under nuclear explosions. 'Zones of split' consist of granite fragments measuring 0.1-3.0 meters. Higher plants were not revealed on ground with big rock fragments. Single individuals of Urtica wens, Setaria viridis are found on ground with small rock fragments. Rarefied aggregations constituted by Artemisia frigida, Festuca valesiaca, Agropyron cristatum develop in small depressions with accumulation of fine earth. Single individuals of petrophytes (Orostachys spinosa, Sedum hybridum, S. purpureum, Patrinia intermedia) appeared on small plots of slightly damaged areas of crests of the mountain ridges. Technogene screens are constituted by granite fragments measuring 0.03-1.0 meter. Higher plants were not found here. Only lower part of the screens sometimes is covered by shrubs - Rosa spinosissima, R. laxa, Spiraea trilobata, Lonicera microphylla, Berberis sibirica are found more rarely. Aggregations of weed plants (Artemisia scoparia, A. sieversiana, Amaranthus retroflexus) develop on orifice-side areas of the adits. We revealed development of adaptation signs of Melilotus albus and Kochia sieversiana growing in conditions of radiation pollution (PED of γ-irradiation 200-700 μR/h). Shape and dimensions of blade

  15. Structural, physiognomic and above-ground biomass variation in savanna–forest transition zones on three continents – how different are co-occurring savanna and forest formations?

    E. M. Veenendaal

    2015-05-01

    Full Text Available Through interpretations of remote-sensing data and/or theoretical propositions, the idea that forest and savanna represent "alternative stable states" is gaining increasing acceptance. Filling an observational gap, we present detailed stratified floristic and structural analyses for forest and savanna stands located mostly within zones of transition (where both vegetation types occur in close proximity in Africa, South America and Australia. Woody plant leaf area index variation was related to tree canopy cover in a similar way for both savanna and forest with substantial overlap between the two vegetation types. As total woody plant canopy cover increased, so did the relative contribution of middle and lower strata of woody vegetation. Herbaceous layer cover declined as woody cover increased. This pattern of understorey grasses and herbs progressively replaced by shrubs as the canopy closes over was found for both savanna and forests and on all continents. Thus, once subordinate woody canopy layers are taken into account, a less marked transition in woody plant cover across the savanna–forest-species discontinuum is observed compared to that inferred when trees of a basal diameter > 0.1 m are considered in isolation. This is especially the case for shrub-dominated savannas and in taller savannas approaching canopy closure. An increased contribution of forest species to the total subordinate cover is also observed as savanna stand canopy closure occurs. Despite similarities in canopy-cover characteristics, woody vegetation in Africa and Australia attained greater heights and stored a greater amount of above-ground biomass than in South America. Up to three times as much above-ground biomass is stored in forests compared to savannas under equivalent climatic conditions. Savanna–forest transition zones were also found to typically occur at higher precipitation regimes for South America than for Africa. Nevertheless, consistent across all three

  16. Nuclear Thermal Propulsion Ground Test History

    Gerrish, Harold P.

    2014-01-01

    Nuclear Thermal Propulsion (NTP) was started in 1955 under the Atomic Energy Commission as project Rover and was assigned to Los Alamos National Laboratory. The Nevada Test Site was selected in 1956 and facility construction began in 1957. The KIWI-A was tested on July 1, 1959 for 5 minutes at 70MW. KIWI-A1 was tested on July 8, 1960 for 6 minutes at 85MW. KIWI-A3 was tested on October 10, 1960 for 5 minutes at 100MW. The National Aeronautics and Space Administration (NASA) was formed in 1958. On August 31, 1960 the AEC and NASA established the Space Nuclear Propulsion Office and named Harold Finger as Director. Immediately following the formation of SNPO, contracts were awarded for the Reactor In Flight Test (RIFT), master plan for the Nuclear Rocket Engine Development Station (NRDS), and the Nuclear Engine for Rocket Vehicle Application (NERVA). From December 7, 1961 to November 30, 1962, the KIWI-B1A, KIWI-B1B, and KIWI-B4A were tested at test cell A. The last two engines were only tested for several seconds before noticeable failure of the fuel elements. Harold Finger called a stop to any further hot fire testing until the problem was well understood. The KIWI-B4A cold flow test showed the problem to be related to fluid dynamics of hydrogen interstitial flow causing fuel element vibrations. President Kennedy visited the NTS one week after the KIWI-B4A failure and got to see the engine starting to be disassembled in the maintenance facility. The KIWI-B4D and KIWI-B4E were modified to not have the vibration problems and were tested in test cell C. The NERVA NRX program started testing in early 1964 with NRX-A1 cold flow test series (unfueled graphite core), NRX-A2 and NRX-A3 power test series up to 1122 MW for 13 minutes. In March 1966, the NRX-EST (Engine System Test) was the first breadboard using flight functional relationship and total operating time of 116 minutes. The NRX-EST demonstrated the feasibility of a hot bleed cycle. The NRX-A5 had multiple start

  17. Traditional nuclear physics as a test of nuclear exotics

    The review considers the testing of some exotic hypotheses about the properties of the nucleon in a nuclear medium in phenomena of traditional nuclear physics. The hypothesis of nucleon swelling proposed to explain the EMC effects is considered in detail. The consequences of this hypothesis for the charge densities and cross sections for scattering of fast electrons and protons by nuclei are analyzed. Also considered are the Nolen--Schiffer anomaly, the Coulomb sum rule for inelastic electron scattering, y scaling, and some other nuclear processes. It is shown that one can estimate the possible scale of nuclear exotics by analyzing many of these phenomena. Thus, examination of high-precision data on the elastic scattering of electrons with energy 500--700 MeV using density distributions calculated on the basis of the self-consistent theory of finite Fermi systems yields a restriction on the amount of nucleon swelling: α=δrN/rN approx-lt 10%. A similar analysis for protons with energy 0.8--1.0 GeV using Glauber theory gives α approx-lt 6%. An even more stringent restriction, α approx-lt 3%, follows from data on y scaling in 56Fe

  18. Evaluating Generic Pantropical Allometric Models for the Estimation of Above-Ground Biomass in the Teak Plantations of Southern Western Ghats, India

    S. Sandeep

    2015-09-01

    Full Text Available The use of suitable tree biomass allometric equations is crucial for making precise and non- destructive estimation of carbon storage and biomass energy values. The aim of this research was to evaluate the accuracy of the most commonly used pantropical allometric models and site-specific models to estimate the above-ground biomass (AGB in different aged teak plantations of Southern Western Ghats of India. For this purpose, the AGB data measured for 70 trees with diameter >10 cm from different aged teak plantations in Kerala part of Southern Western Ghats following destructive procedure was used. The results show that site specific models based on a single predictor variable diameter at breast height (dbh, though simple, may grossly increase the uncertainty across sites. Hence, a generic model encompassing dbh, height and wood specific gravity with sufficient calibration taking into account different forest types is advised for the tropical forest systems. The study also suggests that the commonly used pantropical models should be evaluated for different ecosystems prior to their application at national or regional scales.

  19. Above-ground biomass and carbon estimates of Shorea robusta and Tectona grandis forests using QuadPOL ALOS PALSAR data

    Behera, M. D.; Tripathi, P.; Mishra, B.; Kumar, Shashi; Chitale, V. S.; Behera, Soumit K.

    2016-01-01

    Mechanisms to mitigate climate change in tropical countries such as India require information on forest structural components i.e., biomass and carbon for conservation steps to be implemented successfully. The present study focuses on investigating the potential use of a one time, QuadPOL ALOS PALSAR L-band 25 m data to estimate above-ground biomass (AGB) using a water cloud model (WCM) in a wildlife sanctuary in India. A significant correlation was obtained between the SAR-derived backscatter coefficient (σ°) and the field measured AGB, with the maximum coefficient of determination for cross-polarized (HV) σ° for Shorea robusta, and the weakest correlation was observed with co-polarized (HH) σ° for Tectona grandis forests. The biomass of S. robusta and that of T. grandis were estimated on the basis of field-measured data at 444.7 ± 170.4 Mg/ha and 451 ± 179.4 Mg/ha respectively. The mean biomass values estimated using the WCM varied between 562 and 660 Mg/ha for S. robusta; between 590 and 710 Mg/ha for T. grandis using various polarized data. Our results highlighted the efficacy of one time, fully polarized PALSAR data for biomass and carbon estimate in a dense forest.

  20. Ultraviolet-B Radiation and Nitrogen Affect Nutrient Concentrations and the Amount of Nutrients Acquired by Above-Ground Organs of Maize

    Carlos M. Correia

    2012-01-01

    Full Text Available UV-B radiation effects on nutrient concentrations in above-ground organs of maize were investigated at silking and maturity at different levels of applied nitrogen under field conditions. The experiment simulated a 20% stratospheric ozone depletion over Portugal. At silking, UV-B increased N, K, Ca, and Zn concentrations, whereas at maturity Ca, Mg, Zn, and Cu increased and N, P and Mn decreased in some plant organs. Generally, at maturity, N, Ca, Cu, and Mn were lower, while P, K, and Zn concentrations in stems and nitrogen-use efficiency (NUE were higher in N-starved plants. UV-B and N effects on shoot dry biomass were more pronounced than on nutrient concentrations. Nutrient uptake decreased under high UV-B and increased with increasing N application, mainly at maturity harvest. Significant interactions UV-B x N were observed for NUE and for concentration and mass of some elements. For instance, under enhanced UV-B, N, Cu, Zn, and Mn concentrations decreased in leaves, except on N-stressed plants, whereas they were less affected by N nutrition. In order to minimize nutritional, economical, and environmental negative consequences, fertiliser recommendations based on element concentration or yield goals may need to be adjusted.

  1. The Effect of Above-Ground Medium Voltage Power Lines on Displaying Site Selection of the Great Bustard (Otis Tarda in Central Hungary

    Lóránt Miklós

    2015-02-01

    Full Text Available Our study was conducted in the Upper-Kiskunság region, Central Hungary, which hosts the largest Pannonian population of the Great Bustard (Otis tarda. The influence of the presence of aboveground medium voltage power lines on displaying site selection of Great Bustard males was investigated. The results revealed that displaying males totally reject the sites located within 350-400 m or closer to medium voltage power lines as displaying sites and show relative rejection towards potential displaying sites located at a distance between 500 and 1000 m far from power lines. Surprisingly, the overall negative effects influence much larger part of the potential displaying grounds, up to the distance to 3500 m from power lines. It can be declared that power lines reduce the extent of suitable displaying sites of the Great Bustards in the Upper-Kiskunság region. Accordingly, installation of new above-ground power lines (and other kind of wires, such as high voltage power lines, optical cables etc. would further reduce the extent of suitable displaying sites.

  2. North Korea’s nuclear test

    Radchenko, Sergey

    2009-01-01

    North Korea’s nuclear test serves several purposes. Its first purpose is to bolster the flagging legitimacy of the regime and, by drumming up war hysteria, achieve domestic mobilization in the face of mounting internal difficulties. Throughout North Korea’s turbulent history, the regime has periodically resorted to war hysteria, at times on even grander scale than what we have recently seen. North Korea’s Songun (army-first) policy requires periodic crises to maintain the myth of ...

  3. Atmospheric methods for nuclear test monitoring

    The U.S. DOE sponsored research investigating atmospheric infrasound as a means of detecting both atmospheric and underground nuclear tests. Various detection schemes were examined and were found to be effective for different situations. It has been discovered that an enhanced sensitivity is realizable for the very lowest frequency disturbances by detecting the infrasound at the top of the atmosphere using ratio sound techniques. These techniques are compared to more traditional measurement schemes

  4. Biaxial dynamic testing of nuclear containment steel

    A test program has been initiated at the laboratories of the European Union Joint Research Centre of Ispra to investigate combined effects of high strain rates and biaxial stresses. The purpose is to assess the material behavior up to rupture in the special conditions which are produced during an explosion inside a nuclear metal containment. In the paper the main features of the campaign are discussed. (author). 19 refs., 4 figs

  5. Non-Nuclear Testing of Fission Technologies at NASA MSFC

    Houts, Robert G.; Pearson, J. Boise; Aschenbrenner, Kenneth C.; Bradley, David E.; Dickens, Ricky E.; Emrich, William J.; Garber, Anne E.; Godfroy, Thomas J.; Harper, Roger T.; Martin, Jim J.; Polzin, Kurt A.; Schoenfeld, Michael P.; Webster, Kenneth L.

    2011-01-01

    Highly realistic non-nuclear testing can be used to investigate and resolve potential issues with space nuclear power and propulsion systems. Non-nuclear testing is particularly useful for systems designed with fuels and materials operating within their demonstrated nuclear performance envelope. Non-nuclear testing also provides an excellent way for screening potential advanced fuels and materials prior to nuclear testing, and for investigating innovative geometries and operating regimes. Non-nuclear testing allows thermal hydraulic, heat transfer, structural, integration, safety, operational, performance, and other potential issues to be investigated and resolved with a greater degree of flexibility and at reduced cost and schedule compared to nuclear testing. The primary limit of non-nuclear testing is that nuclear characteristics and potential nuclear issues cannot be directly investigated. However, non-nuclear testing can be used to augment the potential benefit from any nuclear testing that may be required for space nuclear system design and development. This paper describes previous and ongoing non-nuclear testing related to space nuclear systems at NASA s Marshall Space Flight Center (MSFC).

  6. Environmental assessment report: Nuclear Test Technology Complex

    The US Department of Energy (USDOE) is planning to construct and operate a structure, designated the Nuclear Test Technology Complex (NTTC), on a site located west of and adjacent to the Lawrence Livermore National Laboratory. The NTTC is designed to house 350 nuclear test program personnel, and will accommodate the needs of the entire staff of the continuing Nuclear Test Program (NTP). The project has three phases: land acquisition, facility construction and facility operation. The purpose of this environmental assessment report is to describe the activities associated with the three phases of the NTTC project and to evaluate potential environmental disruptions. The project site is located in a rural area of southeastern Alameda County, California, where the primary land use is agriculture; however, the County has zoned the area for industrial development. The environmental impacts of the project include surface disturbance, high noise levels, possible increases in site erosion, and decreased air quality. These impacts will occur primarily during the construction phase of the NTTC project and can be mitigated in part by measures proposed in this report

  7. New test of the nuclear statistical model

    High resolution proton resonance measurements provide a new test of the nuclear statistical model. For a sequence of levels with the same spin and parity the width correlation rho/sub W/ and the amplitude correlation rho/sub A/ are determined separately for the inelastic decay channels. The observed correlations average about 0.5 and are ascribed to direction reactions between the inelastic channels. For a multivariate Gausian distribution rho/sup 2//sub A//rho/sub W/=1. The present data provide the first opportunity to test this prediction directly

  8. Testing Iodine Filters for Nuclear Installations

    The removal efficiency of iodine filters for nuclear installations has been tested The test method in use includes laboratory tests of the adsorber material (under MCA conditions for temperature, relative humidity, pressure, loading, stay time and bed depth) and in-place tests at the site of the installation. For removal of methyl iodide under high relative humidity Kl-impregnated charcoal is widely used. Most of the data for charcoal removal efficiency available today result from experiments with tracer amounts of CH3131I mixed with CH3127I. Considering MCA conditions, the validity of those data should be confirmed for specific activities on charcoal 103 - 106 times higher. Experimental data are given for realistic loadings with CH3131I up to 10 Ci/g charcoal under 100% relative humidity. For standard laboratory adsorber tests a method is discussed for humidification and control of gas streams up to 100% relative humidity at elevated temperatures. The apparatus used is described. Experimental data are given for the removal efficiency and the adsorption of water in charcoal samples from long-time tests under 100% relative humidity. The overall test period was up to 98 h, simulating the phase of elevated pressure and, therefore, high iodine release from the reactor containment. The reproducibility of long-time tests under extremely high relative humidity is shown and discussed. A description of the hardware for in-place tests is included and results are given. (author)

  9. Field test of wireless sensor network in the nuclear environment

    Wireless sensor networks (WSNs) are appealing options for the health monitoring of nuclear power plants due to their low cost and flexibility. Before they can be used in highly regulated nuclear environments, their reliability in the nuclear environment and compatibility with existing devices have to be assessed. In situ electromagnetic interference tests, wireless signal propagation tests, and nuclear radiation hardness tests conducted on candidate WSN systems at AECL Chalk River Labs are presented. The results are favourable to WSN in nuclear applications. (author)

  10. Field test of wireless sensor network in the nuclear environment

    Li, L., E-mail: lil@aecl.ca [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Wang, Q.; Bari, A. [Univ. of Western Ontario, London, Ontario (Canada); Deng, C.; Chen, D. [Univ. of Electronic Science and Technology of China, Chengdu, Sichuan (China); Jiang, J. [Univ. of Western Ontario, London, Ontario (Canada); Alexander, Q.; Sur, B. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2014-06-15

    Wireless sensor networks (WSNs) are appealing options for the health monitoring of nuclear power plants due to their low cost and flexibility. Before they can be used in highly regulated nuclear environments, their reliability in the nuclear environment and compatibility with existing devices have to be assessed. In situ electromagnetic interference tests, wireless signal propagation tests, and nuclear radiation hardness tests conducted on candidate WSN systems at AECL Chalk River Labs are presented. The results are favourable to WSN in nuclear applications. (author)

  11. Modeling Water and Nutrient Transport through the Soil-Root-Canopy Continuum: Explicitly Linking the Below- and Above-Ground Processes

    Kumar, P.; Quijano, J. C.; Drewry, D.

    2010-12-01

    Vegetation roots provide a fundamental link between the below ground water and nutrient dynamics and above ground canopy processes such as photosynthesis, evapotranspiration and energy balance. The “hydraulic architecture” of roots, consisting of the structural organization of the root system and the flow properties of the conduits (xylem) as well as interfaces with the soil and the above ground canopy, affect stomatal conductance thereby directly linking them to the transpiration. Roots serve as preferential pathways for the movement of moisture from wet to dry soil layers during the night, both from upper soil layer to deeper layers during the wet season (‘hydraulic descent’) and vice-versa (‘hydraulic lift’) as determined by the moisture gradients. The conductivities of transport through the root system are significantly, often orders of magnitude, larger than that of the surrounding soil resulting in movement of soil-moisture at rates that are substantially larger than that through the soil. This phenomenon is called hydraulic redistribution (HR). The ability of the deep-rooted vegetation to “bank” the water through hydraulic descent during wet periods for utilization during dry periods provides them with a competitive advantage. However, during periods of hydraulic lift these deep-rooted trees may facilitate the growth of understory vegetation where the understory scavenges the hydraulically lifted soil water. In other words, understory vegetation with relatively shallow root systems have access to the banked deep-water reservoir. These inter-dependent root systems have a significant influence on water cycle and ecosystem productivity. HR induced available moisture may support rhizosphere microbial and mycorrhizal fungi activities and enable utilization of heterogeneously distributed water and nutrient resources To capture this complex inter-dependent nutrient and water transport through the soil-root-canopy continuum we present modeling

  12. Towards ground-truthing of spaceborne estimates of above-ground life biomass and leaf area index in tropical rain forests

    P. Köhler

    2010-08-01

    Full Text Available The canopy height h of forests is a key variable which can be obtained using air- or spaceborne remote sensing techniques such as radar interferometry or LIDAR. If new allometric relationships between canopy height and the biomass stored in the vegetation can be established this would offer the possibility for a global monitoring of the above-ground carbon content on land. In the absence of adequate field data we use simulation results of a tropical rain forest growth model to propose what degree of information might be generated from canopy height and thus to enable ground-truthing of potential future satellite observations. We here analyse the correlation between canopy height in a tropical rain forest with other structural characteristics, such as above-ground life biomass (AGB (and thus carbon content of vegetation and leaf area index (LAI and identify how correlation and uncertainty vary for two different spatial scales. The process-based forest growth model FORMIND2.0 was applied to simulate (a undisturbed forest growth and (b a wide range of possible disturbance regimes typically for local tree logging conditions for a tropical rain forest site on Borneo (Sabah, Malaysia in South-East Asia. In both undisturbed and disturbed forests AGB can be expressed as a power-law function of canopy height h (AGB = a · hb with an r2 ~ 60% if data are analysed in a spatial resolution of 20 m × 20 m (0.04 ha, also called plot size. The correlation coefficient of the regression is becoming significant better in the disturbed forest sites (r2 = 91% if data are analysed hectare wide. There seems to exist no functional dependency between LAI and canopy height, but there is also a linear correlation (r2 ~ 60% between AGB and the area fraction of gaps in which the canopy is highly disturbed. A reasonable agreement of our results with observations is obtained from a

  13. Subsurface radionuclide investigation of a nuclear test

    Mathews, M.; Hahn, K.; Thompson, J.; Gadeken, L.; Madigan, W.

    1994-08-01

    This paper reports on an environmental investigation into the vertical distribution of radionuclides from a nuclear test. Dalhart is the name of an underground nuclear test that was executed at the Nevada Test Site at a depth of 2100 ft on October 13, 1988. The test occurred below the static water level of 1667 ft and created multiple radioactive isotopes or fission products. These radioactive isotopes penetrated the surrounding formations and chimney region above the test and were retained there. A 19° 9- {7}/{8}-inch diameter slant hole was drilled to sample the geologic material in the chimney region above the Dalhart test for the purpose of assessing the distribution of radioactivity in and around the shot site. A 30-ft core recovered from a vertical depth of 1628 ft in the collapsed zone or chimney region and above the original static water level was found to be free of radionuclides. Drilling was completed to a vertical depth of 2156 ft with the present static water level at a vertical depth of 1644 ft. Gamma-ray spectroscopy log measurements, made within the drill pipe while drilling fluid was pumped through this pipe, indicate that radioactive material produced by the test was present from the vertical depth interval of 1746-2156 ft. Side-wall samples acquired from the vertical depth interval of 1721-2089 ft and analyzed in the field contained radionuclides such as 137Cs, 125Sb, 106Ru, plus the natural radioactive background of potassium, uranium, and thorium. These samples were sent to Los Alamos to determine the complete radionuclide content at each depth. These analyses were used with the gamma-ray spectroscopy logging data to determine the subsurface vertical radionuclide distribution at the Dalhart site.

  14. Subsurface radionuclide investigation of a nuclear test

    This paper reports on an environmental investigation into the vertical distribution of radionuclides from a nuclear test. Dalhart is the name of an underground nuclear test that was executed at the Nevada Test Site at a depth of 2100 ft on October 13, 1988. The test occurred below the static water level of 1667 ft and created multiple radioactive isotopes or fission products. These radioactive isotopes penetrated the surrounding formations and chimney region above the test and were retained there. A 19o 9-7/8-inch diameter slant hole was drilled to sample the geologic material in the chimney region above the Dalhart test for the purpose of assessing the distribution of radioactivity in and around the shot site. A 30-ft core recovered from a vertical depth of 1628 ft in the collapsed zone or chimney region and above the original static water level was found to be free of radionuclides. Drilling was completed to a vertical depth of 2156 ft with the present static water level at a vertical depth of 1644 ft. Gamma-ray spectroscopy log measurements, made within the drill pipe while drilling fluid was pumped through this pipe, indicate that radioactive material produced by the test was present from the vertical depth interval of 1746-2156 ft. Side-wall samples acquired from the vertical depth interval of 1721-2089 ft and analyzed in the field contained radionuclides such as 137Cs, 125Sb, 106Ru, plus the natural radioactive background of potassium, uranium, and thorium. These samples were sent to Los Alamos to determine the complete radionuclide content at each depth. These analyses were used with the gamma-ray spectroscopy logging data to determine the subsurface vertical radionuclide distribution at the Dalhart site

  15. Heavy metal accumulation in the above-ground vegetation and soil around an iron smelting factory in Ile-Ife, southwestern Nigeria

    Emmanuel F. Isola; Olusanya A. Olatunji; Akinjide M. Afolabi; Ademayowa A. Omodara

    2015-01-01

    This study investigated the accumulation of heavy metals in the above-ground vegetation and soil around an iron smelting factory located at the Fashina Area, Ile-Ife, Osun State, southwestern Nigeria. This was with a view to establish baseline data which can be used for assessing the impact of the steel processing industry in the area. Samples of the two most common herbaceous species (Chromolaena odorataand Aspilia africana) around the factory were randomly collected at 10 m away from the wall of the factory, and soil samples were randomly collected at 0–15 cm depths in the same area. The plant species were oven-dried, put through a mixed acid digestion procedure, and, along with soil samples, were analyzed for N, P, K, C, Zn, Pb, Cd, Ni, and Cr using an atomic absorption spectrophotometer. The data obtained were subjected to appropriate descriptive and inferential statistical analyses. The results revealed that the soils were slightly acidic, with pH values of 6.23±0.24 in the dry season and 6.10±0.16 in the rainy season. There was a significant difference (P P > N in both Aspilia africana andChromolaena odorata. In the dry season, C percentage concentration was higher inAspilia africana, while the other elements followed the trend observed in the rainy season. The concentration of Zn was higher inAspilia af-ricana in both the polluted site and the control site in the rainy season, while the concentrations of the other heavy metals were higher inChromolaena odoratain the dry season. This study revealed that the heavy metal concentration varied with the plant species and also with the prevailing seasonal conditions. Also, the accumulation and concentration of heavy metals in both plant species and in the soil indicated a potential hazard of the factory to the local environment.

  16. Above-ground sulfur cycling in adjacent coniferous and deciduous forest and watershed sulfur retention in the Georgia Piedmont, U.S.A.

    Cappellato, R.; Peters, N.E.; Meyers, T.P.

    1998-01-01

    Atmospheric deposition and above-ground cycling of sulfur (S) were evaluated in adjacent deciduous and coniferous forests at the Panola Mountain Research Watershed (PMRW), Georgia U.S.A. Total atmospheric S deposition (wet plus dry) was 12.9 and 12.7 kg ha-1 yr-1 for the deciduous and coniferous forests, respectively, from October 1987 through November 1989. Dry deposition contributes more than 40% to the total atmospheric S deposition, and SO2 is the major source (~55%) of total dry S deposition. Dry deposition to these canopies is similar to regional estimates suggesting that 60-km proximity to emission sources does not noticeably impact dry deposition at PMRW. Below-canopy S fluxes (throughfall plus stemflow) in each forest are 37% higher annually in the deciduous forest than in the coniferous forest. An excess in below-canopy S flux in the deciduous forest is attributed to leaching and higher dry deposition than in the coniferous forest. Total S deposition to the forest floor by throughfall, stemflow and litterfall was 2.4 and 2.8 times higher in the deciduous and coniferous forests, respectively, than annual S growth requirement for foliage and wood. Although A deposition exceeds growth requirement, more than 95% of the total atmospheric S deposition was retained by the watershed in 1988 and 1989. The S retention at PMRW is primarily due to SO2+4 adsorption by iron oxides and hydroxides in watershed soils. The S content in while oak and loblolly pine boles have increased more than 200% in the last 20 yr, possibly reflecting increases in emissions.

  17. Optimizing the number of training areas for modeling above-ground biomass with ALS and multispectral remote sensing in subtropical Nepal

    Rana, Parvez; Gautam, Basanta; Tokola, Timo

    2016-07-01

    Remote sensing-based inventories of above-ground forest biomass (AGB) require a set of training plots representative of the area to be studied, the collection of which is the most expensive part of the analysis. These are time-consuming and costly because the large variety in forest conditions requires more plots to adequately capture this variability. A field campaign in general is challenging and is hampered by the complex topographic conditions, limited accessibility, steep mountainous terrains which increase labor efforts and costs. In addition it is also depend on the ratio between size of study area and number of training plots. In this study, we evaluate the number of training areas (sample size) required to estimate AGB for an area in the southern part of Nepal using airborne laser scanning (ALS), RapidEye and Landsat data. Three experiments were conducted: (i) AGB model performance, based on all the field training plots; (ii) reduction of the sample size, based on the ALS metrics and the AGB distribution; and (iii) prediction of the optimal number of training plots, based on the correlation between the remote sensing and field data. The AGB model was fitted using the sparse Bayesian method. AGB model performance was validated using an independent validation dataset. The effect of the strategies for reducing the sample size was readily apparent for the ALS-based AGB prediction, but the RapidEye and Landsat sensor data failed to capture any such effect. The results indicate that adequate coverage of the variability in tree height and density was an important condition for selecting the training plots. In addition, the ALS-based AGB prediction required the smallest number of training plots and was also quite stable with a small number of field plots.

  18. Assessment of Above-Ground Biomass of Borneo Forests through a New Data-Fusion Approach Combining Two Pan-Tropical Biomass Maps

    Andreas Langner

    2015-08-01

    Full Text Available This study investigates how two existing pan-tropical above-ground biomass (AGB maps (Saatchi 2011, Baccini 2012 can be combined to derive forest ecosystem specific carbon estimates. Several data-fusion models which combine these AGB maps according to their local correlations with independent datasets such as the spectral bands of SPOT VEGETATION imagery are analyzed. Indeed these spectral bands convey information about vegetation type and structure which can be related to biomass values. Our study area is the island of Borneo. The data-fusion models are evaluated against a reference AGB map available for two forest concessions in Sabah. The highest accuracy was achieved by a model which combines the AGB maps according to the mean of the local correlation coefficients calculated over different kernel sizes. Combining the resulting AGB map with a new Borneo land cover map (whose overall accuracy has been estimated at 86.5% leads to average AGB estimates of 279.8 t/ha and 233.1 t/ha for forests and degraded forests respectively. Lowland dipterocarp and mangrove forests have the highest and lowest AGB values (305.8 t/ha and 136.5 t/ha respectively. The AGB of all natural forests amounts to 10.8 Gt mainly stemming from lowland dipterocarp (66.4%, upper dipterocarp (10.9% and peat swamp forests (10.2%. Degraded forests account for another 2.1 Gt of AGB. One main advantage of our approach is that, once the best fitting data-fusion model is selected, no further AGB reference dataset is required for implementing the data-fusion process. Furthermore, the local harmonization of AGB datasets leads to more spatially precise maps. This approach can easily be extended to other areas in Southeast Asia which are dominated by lowland dipterocarp forest, and can be repeated when newer or more accurate AGB maps become available.

  19. Modeling nuclear explosion

    Redd, Jeremy; Panin, Alexander

    2012-10-01

    As a result of the Nuclear Test Ban Treaty, no nuclear explosion tests have been performed by the US since 1992. This appreciably limits valuable experimental data needed for improvement of existing weapons and development of new ones, as well as for use of nuclear devices in non-military applications (such as making underground oil reservoirs or compressed air energy storages). This in turn increases the value of numerical modeling of nuclear explosions and of their effects on the environment. We develop numerical codes simulating fission chain reactions in a supercritical U and Pu core and the dynamics of the subsequent expansion of generated hot plasma in order to better understand the impact of such explosions on their surroundings. The results of our simulations (of both above ground and underground explosions) of various energy yields are presented.

  20. Characteristics of Radioactive Pollutant From Ground Testing of Nuclear Propulsion Reactors

    The radioactive pollutant resulting from the ground testing of nuclear propulsion reactors is initially released as a distributed vertical line source. The resultant ground-level contamination pattern is much like what would be expected from a two-point release; one at ground level and a second at about 2000 m above ground. The material in the cloud is composed of volatile fission products or the daughters of volatile fission products. The major contributors to the activity are in three mass groups, 89 to 93, 129 to 135, and 140 to 144. The strontiums and yttriums have been measured on the ground and aloft, and tin and antimony have been measured in the cloud aloft as well. In the third group, barium and lanthanum have been measured on the ground and aloft, and cerium has been measured in the aircraft samples. It appears that the reason for the discontinuity between the last two groups is due to xenon remaining in the reactor. The pollutant, at distance, behaves as two clouds, one made up of gaseous material and the second of particulate. The activities of the two remain in a nearly constant ratio out to 25 miles along the hot line. It appears that the gaseous cloud suffers more lateral diffusion than the particulate fraction. The particulate fraction appears to be composed of particles principally in the submicron range. Depletion of the cloud seems to be largely by turbulent impaction or sorption. Correlation between airborne levels and ground concentrations is poor. Deposition velocities which have been measured are statistical in nature and show a log normal distribution with a mean of 0.5 cm/sec and a geometric standard deviation of about 10. The concept of a constant deposition velocity is most probably not valid. (author)

  1. Rehabilitation of nuclear test site at Maralinga

    A program to rehabilitate contaminated areas at the Maralinga Nuclear Test Range in South Australia is being undertaken by the Australian Department of Primary Industries and Energy (DPIE). A major part of the program is directed at reducing the risk presented by the contaminated debris buried at Taranaki, Maralinga's most heavily contaminated site. The rehabilitation program is using the insitu vitrification technology developed for the US Department of Energy. The program is now in its third phase, involving the construction of the full-scale treatment plant. This will be completed later this year. The fourth and last phase will involve the treatment of the Taranaki pits. This will commence in 1998. Tests carried out so far indicated that the normalized leach rates for all oxides in the vitrified product were less than 0.1g/m2. ills

  2. Sensitivity of Backscatter Intensity of ALOS/PALSAR to Above-ground Biomass and Other Biophysical Parameters of Boreal Forests in Alaska and Japan

    Suzuki, R.; Hayashi, M.; Kim, Y.; Ishii, R.; Kobayashi, H.; Shoyama, K.; Adachi, M.; Takahashi, A.; Saigusa, N.; Ito, A.

    2012-12-01

    For the better understanding of the carbon cycle in the global environment, investigations on the spatio-temporal variation of the carbon stock which is stored as vegetation biomass is important. The backscatter intensity of "Phased Array type L-band Synthetic Aperture Radar (PALSAR)" onboard the satellite "Advanced Land Observing Satellite (ALOS)" provides us the information which is applicable to estimate the forest above-ground biomass (AGB). This study examines the sensitivity of the backscatter intensity of ALOS/PALSAR to the forest AGB and other biophysical parameters (tree height, tree diameter at breast height (DBH), and tree stand density) for boreal forests in two geographical regions of Alaska and Kushiro, northern Japan, and compares the sensitivities in two regions. In Alaska, a forest survey was executed in the south-north transect (about 300 km long) along a trans-Alaska pipeline which profiles the ecotone from the boreal forest to tundra in 2007. Forest AGBs and other biophysical parameters at 29 forests along the transect were measured by Bitterlich method. In Kushiro, a forest survey was carried out at 42 forests in 2011 and those parameters were similarly obtained by Bitterlich method. 20 and 2 scenes of ALOS/PALSAR FBD Level 1.5 data that cover the regions in Alaska and Kushiro, respectively, were collected and mosaicked. Backscatter intensities of ALOS/PALSAR in HH (horizontally polarized transmitted and horizontally polarized received) and HV (horizontally polarized transmitted and vertically polarized received) modes were compared with the forest AGB and other biophysical parameters. The intensity generally increased with the increase of those biophysical parameters in both HV and HH modes, but the intensity in HV mode generally had a stronger correlation to those parameters than in HH mode in both Alaska and Kushiro. The HV intensity had strong correlation to the forest AGB and DBH, while weak correlation to the tree stand density in Alaska

  3. Studies of Health Effects from Nuclear Testing near the Semipalatinsk Nuclear Test Site, Kazakhstan

    Bernd Grosche

    2015-05-01

    Full Text Available The nuclear bomb testing conducted at the Semipalatinsk nuclear test site in Kazakhstan is of great importance for today’s radiation protection research, particularly in the area of low dose exposures. This type of radiation is of particular interest due to the lack of research in this field and how it impacts population health. In order to understand the possible health effects of nuclear bomb testing, it is important to determine what studies have been conducted on the effects of low dose exposure and dosimetry, and evaluate new epidemiologic data and biological material collected from populations living in proximity to the test site. With time, new epidemiological data has been made available, and it is possible that these data may be linked to biological samples. Next to linking existing and newly available data to examine health effects, the existing dosimetry system needs to be expanded and further developed to include residential areas, which have not yet been taken into account. The aim of this paper is to provide an overview of previous studies evaluating the health effects of nuclear testing, including some information on dosimetry efforts, and pointing out directions for future epidemiologic studies.

  4. Experimental test of nuclear magnetization distribution and nuclear structure models

    Models exist that ascribe the nuclear magnetic fields to the presence of a single nucleon whose spin is not neutralized by pairing it up with that of another nucleon; other models assume that the generation of the magnetic field is shared among some or all nucleons throughout the nucleus. All models predict the same magnetic field external to the nucleus since this is an anchor provided by experiments. The models differ, however, in their predictions of the magnetic field arrangement within the nucleus for which no data exist. The only way to distinguish which model gives the correct description of the nucleus would be to use a probe inserted into the nucleus. The goal of our project was to develop exactly such a probe and to use it to measure fundamental nuclear quantities that have eluded experimental scrutiny. The need for accurately knowing such quantities extends far beyond nuclear physics and has ramifications in parity violation experiments on atomic traps and the testing of the standard model in elementary particle physics. Unlike scattering experiments that employ streams of free particles, our technique to probe the internal magnetic field distribution of the nucleus rests on using a single bound electron. Quantum mechanics shows that an electron in the innermost orbital surrounding the nucleus constantly dives into the nucleus and thus samples the fields that exist inside. This sampling of the nucleus usually results in only minute shifts in the electron s average orbital, which would be difficult to detect. By studying two particular energy states of the electron, we can, however, dramatically enhance the effects of the distribution of the magnetic fields in the nucleus. In fact about 2% of the energy difference between the two states, dubbed the hyperfine splitting, is determined by the effects related to the distribution of magnetic fields in the nucleus, A precise measurement of this energy difference (better than 0.01%) would then allow us to place

  5. Reload Startup Physics Tests for Tianwan Nuclear Power station

    This paper briefly describes the test purposes, test items, test schedules and test equipment's for reload startup physics test's on Unit 1 and 2 of Tianwan Nuclear Power station. Then, an overview of the previous thrice tests and evaluations on the tests results are presented. In the end, the paper shows the development and work direction of optimization project for reload startup physics tests on Unit 1 and 2 of Tianwan Nuclear Power station. (Authors)

  6. Estimating Above-Ground Biomass Within the Footprint of an Eddy-Covariance Flux Tower: Continuous LiDAR Based Estimates Compared With Discrete Inventory and Disturbance History Based Stratification Boundaries

    Ferster, C. J.; Trofymow, J. A.; Coops, N. C.; Chen, B.; Black, T. A.

    2008-12-01

    Eddy-covariance (EC) flux towers provide data about carbon (C) exchange between land and the atmosphere at an ecosystem scale. However, important research questions need to be addressed when placing EC flux towers in complex heterogeneous forest landscapes, such as the coastal forests of Western Canada. Recently available footprint analysis, which describes the contribution function and catchment area where EC flux is being measured, can be used to relate EC flux tower measurements with the biological structure and carbon stock distributions of complex forest landscapes. In this study, above ground biomass is estimated near an EC flux tower using two approaches. In the first approach, a remote sensing based surface representing above ground biomass was estimated using small footprint, discrete return, light detection and ranging (LiDAR) data. Plot level LiDAR metrics were supplemented with metrics calculated using individual tree detection. A multiple regression model was developed to estimate above ground biomass using ground plot and LiDAR data, and then the model was applied across the EC flux footprint area to estimate the spatial distribution of above ground biomass. In the second approach, line boundaries from forest inventory, disturbance history, and site series were used to delineate discrete stratification units and the measured groundplot data assigned to the various strata. Within the heterogeneous tower footprint area, footprint weighting allows us to compare and contrast above ground biomass estimates from these two approaches. Using this methodology we then plan to compare, for the same period, ground-based measurements of ecosystem C stock changes with accumulative EC measured net ecosystem C flux.

  7. Yesterday's, today's and tomorrow's nuclear tests of India and Pakistan

    This paper presents the historical aspects that led India and Pakistan to develop nuclear weapons and to perform nuclear weapon tests: weapons acquisition: today's military capacity, help from foreign countries; motivations: nuclear programs, geo-political aspects; results and potentialities; consequences for the non-proliferation systems and for the cut-off convention and test-ban treaties; and the geo-strategic consequences of todays's military nuclear capacity of India and Pakistan. (J.S.)

  8. Development of nuclear technologies and conversion of nuclear weapon testing system infrastructure in Kazakhstan

    The article gives a brief description of the work done by the National Nuclear Center of the Republic of Kazakhstan in development of nuclear technology and conversion of nuclear weapon testing infrastructure in Kazakhstan. Content and trends of works are as follows: 1. Peaceful use of all physical facilities, created earlier for nuclear tests in Kazakhstan; 2. Development of methods and technologies for safe nuclear reactors use; 3. Examination of different materials in field of great neutron flow for thermonuclear reactor's first wall development; 4. Liquidation of all wells, which were formed in the results of underground nuclear explosions in Degelen mountain massif of former Semipalatinsk test site; 5. Study of consequences of nuclear tests in West Kazakhstan (territory of Azgir test site and Karachaganak oil field); 6. Study of radiological situation on the Semipalatinsk test site and surrounding territories; 7. Search of ways for high-level radioactive wastes disposal; 8. Construction of safe nuclear power plants in Kazakhstan

  9. Some Qualitative Requirements for Testing of Nuclear Emergency Response Robots

    Eom, Heungseop; Cho, Jai Wan; Choi, Youngsoo; Jeong, Kyungmin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    Korea Atomic Energy Research Institute (KAERI) is carrying out the project 'Development of Core Technology for Remote Response in Nuclear Emergency Situation', and as a part of the project, we are studying the reliability and performance requirements of nuclear emergency response robots. In this paper, we described some qualitative requirements for testing of nuclear emergency response robots which are different to general emergency response robots. We briefly introduced test requirements of general emergency response robots and described some qualitative aspects of test requirements for nuclear emergency response robots. When considering an immature field-robot technology and variety of nuclear emergency situations, it seems hard to establish quantitative test requirements of these robots at this time. However, based on studies of nuclear severe accidents and the experience of Fukushima NPP accident, we can expect some test requirements including quantitative ones for nuclear emergency response robots.

  10. Some Qualitative Requirements for Testing of Nuclear Emergency Response Robots

    Korea Atomic Energy Research Institute (KAERI) is carrying out the project 'Development of Core Technology for Remote Response in Nuclear Emergency Situation', and as a part of the project, we are studying the reliability and performance requirements of nuclear emergency response robots. In this paper, we described some qualitative requirements for testing of nuclear emergency response robots which are different to general emergency response robots. We briefly introduced test requirements of general emergency response robots and described some qualitative aspects of test requirements for nuclear emergency response robots. When considering an immature field-robot technology and variety of nuclear emergency situations, it seems hard to establish quantitative test requirements of these robots at this time. However, based on studies of nuclear severe accidents and the experience of Fukushima NPP accident, we can expect some test requirements including quantitative ones for nuclear emergency response robots

  11. Radioiodine prediction model for nuclear tests

    Over a 5-year period, 14 major experiments were conducted to investigate the air-forage-cow-milk system for transfer of radioiodine. The experiments included controlled releases using prepared aerosols, planned releases during Plowshare cratering tests, and releases due to accidental venting of underground nuclear tests. Two or more groups of dairy cows, three to six cows per group, were used in each experiment to study the effect on radioiodine transfer of such factors as: the mode of exposure, the type and state of forage fed, the type of aerosol, and variations in feeding practices. In each experiment, measurements were made of the total radioiodine intake and output in milk of the cows, the concentrations in forage and milk, the gaseous and particulate air concentrations, the open-field gamma exposure rate, and the deposition per unit area. The mean values of the experimental data are assembled in this report and are used to develop the parameters for a standard milk excretion pattern for dairy cows and to develop predictive equations for radioiodine. The resultant equations, for predicting the infinite dose to a 2-gram human thyroid caused by ingestion of 131I, are presented

  12. The risk of leukaemia in young children from exposure to tritium and carbon-14 in the discharges of German nuclear power stations and in the fallout from atmospheric nuclear weapons testing.

    Wakeford, Richard

    2014-05-01

    Towards the end of 2007, the results were published from a case-control study (the "KiKK Study") of cancer in young children, diagnosed tritium and carbon-14 discharges in this supposedly severe underestimation of risk. Both (3)H and (14)C are generated naturally in the upper atmosphere, and substantial increases in these radionuclides in the environment occurred as a result of their production by atmospheric testing of nuclear weapons during the late 1950s and early 1960s. If the leukaemogenic effect of these radionuclides has been seriously underestimated to the degree necessary to explain the KiKK Study findings, then a pronounced increase in the worldwide incidence of leukaemia among young children should have followed the notably elevated exposure to (3)H and (14)C from nuclear weapons testing fallout. To investigate this hypothesis, the time series of incidence rates of leukaemia among young children <5 years of age at diagnosis has been examined from ten cancer registries from three continents and both hemispheres, which include registration data from the early 1960s or before. No evidence of a markedly increased risk of leukaemia in young children following the peak of above-ground nuclear weapons testing, or that incidence rates are related to level of exposure to fallout, is apparent from these registration rates, providing strong grounds for discounting the idea that the risk of leukaemia in young children from (3)H or (14)C (or any other radionuclide present in both nuclear weapons testing fallout and discharges from nuclear installations) has been grossly underestimated and that such exposure can account for the findings of the KiKK Study. PMID:24477409

  13. Current Status of Nuclear Fuel Irradiation Test at HANARO

    Yang, Seong Woo; Park, Seung Jae; Shin, Yoon Taeg; Choo, Kee Nam; Cho, Man Soon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The in-pile testing of HANARO demand of not only the reactor core and structure material but also the nuclear fuel is recently increased to verify its irradiation performance, some fuel irradiation tests were planned and conducted using the irradiation test capsule in OR irradiation hole at HANARO. In this paper, the current status of irradiation test for the nuclear fuels at HANARO is reported. The current status of nuclear fuel irradiation test was reported. The irradiation test for plate, particle, pellet and metallic fuel for the development of research reactor, VHTR, LWR, SFR was planned and conducted at HANARO.

  14. Calculated concentrations of any radionuclide deposited on the ground by release from underground nuclear detonations, tests of nuclear rockets, and tests of nuclear ramjet engines

    This report presents calculated gamma radiation exposure rates and ground deposition of related radionuclides resulting from three types of event that deposited detectable radioactivity outside the Nevada Test Site complex, namely, underground nuclear detonations, tests of nuclear rocket engines and tests of nuclear ramjet engines

  15. Nuclear Materials Management for the Nevada Test Site (NTS)

    The Nevada Test Site (NTS) has transitioned from its historical role of weapons testing to a broader role that is focused on being a solution to multiple National Nuclear Security Administration (NNSA) challenges and opportunities with nuclear materials for the nation. NTS is supporting other NNSA sites challenged with safe nuclear materials storage and disposition. NNSA, with site involvement, is currently transforming the nuclear stockpile and supporting infrastructure to meet the 2030 vision. Efforts are under way to make the production complex smaller, more consolidated, and more modern. With respect to the nuclear material stockpile, the NNSA sites are currently reducing the complex nuclear material inventory through dispositioning and consolidating nuclear material. This includes moving material from other sites to NTS. State-of-the-art nuclear material management and control practices at NTS are essential for NTS to ensure that these new activities are accomplished in a safe, secure, efficient, and environmentally responsible manner. NTS is aggressively addressing this challenge

  16. Nuclear fuel manufacturing. Testing nuclear materials and materials of nuclear interest

    Adopting CANDU system for nuclear energy production in Romania was argued by utilization of natural uranium, no isotopic enrichment being required for the fissile nuclide. Manufacturing the nuclear fuel, testing nuclear materials and materials for nuclear use, designing and realisation of the installations associated to the fabrication and testing were the main directions of activity of INR - Pitesti, from its inception. The report presents the main results in the fabrication of nuclear fuel and material testing. There are described the stages of fabrication of sintered powders of uranium dioxide starting from uranium nitrate solution. Efforts for refining uranium nitrate up to the required level of nuclear purity were eventually finalised by working out a technology of sintered uranium dioxide, a technology later on transferred to the pilot plant 'R' and then to the industrial Unit 'E'. In parallel, activities for processing of half-finished Zircaloy 4, for fabrication of sheathing components of uranium dioxide pellets and assembling of fuel clusters were developed. Over 100 experimental fuel elements were manufactured and pre-irradiation characterized in order to check the fabrication technologies as well as the computer codes for calculation of the CANDU type fuel behavior in normal and accident conditions. The irradiation testing of the fuel manufactured in INR was done in the NRU (Canada), MZFR (Germany), BR - 2 (Belgium) and TRIGA (Pitesti, Romania) reactors, while the post-irradiation examination was carried out in the hot loops of the INR reactor. In addition, other relating activities were developed as for instance: establishing technologies for re-entry in the fabrication flow of the UO2 sintered powders, of some recyclable materials and integral recovery of uranium from wastes; testing of the materials to be used in the UO2 sintering powders and identification of reagents and indigenous materials; implementation of the quality assurance systems; testing

  17. Analysis of North Korea's Nuclear Tests under Prospect Theory

    North Korea has chosen nuclear weapons as the means to protect its sovereignty. Despite international society's endeavors and sanctions to encourage North Korea to abandon its nuclear ambition, North Korea has repeatedly conducted nuclear testing. In this paper, the reason for North Korea's addiction to a nuclear arsenal is addressed within the framework of cognitive psychology. The prospect theory addresses an epistemological approach usually overlooked in rational choice theories. It provides useful implications why North Korea, being under a crisis situation has thrown out a stable choice but taken on a risky one such as nuclear testing. Under the viewpoint of prospect theory, nuclear tests by North Korea can be understood as follows: The first nuclear test in 2006 is seen as a trial to escape from loss areas such as financial sanctions and regime threats; the second test in 2009 was interpreted as a consequence of the strategy to recover losses by making a direct confrontation against the United States; and the third test in 2013 was understood as an attempt to strengthen internal solidarity after Kim Jong-eun inherited the dynasty, as well as to enhance bargaining power against the United States. Thus, it can be summarized that Pyongyang repeated its nuclear tests to escape from a negative domain and to settle into a positive one. In addition, in the future, North Korea may not be willing to readily give up its nuclear capabilities to ensure the survival of its own regime

  18. Nuclear test-experimental science annual report, Fiscal year 1990

    Fiscal year 1990 was another year of outstanding accomplishments for the Nuclear Test-Experimental Science (NTES) Program at Lawrence Livermore National Laboratory (LLNL). We continued to make progress to enhance the experimental science in the Weapons Program and to improve the operational efficiency and productivity of the Nuclear Test Program

  19. United States nuclear tests, July 1945 through September 1992

    1994-12-01

    This document lists chronologically and alphabetically by name all nuclear tests and simultaneous detonations conducted by the United States from July 1945 through September 1992. Several tests conducted during Operation Dominic involved missile launches from Johnston Atoll. Several of these missile launches were aborted, resulting in the destruction of the missile and nuclear device either on the pad or in the air.

  20. Cancer in People Exposed to Nuclear Weapons Testing

    ... Compensation Programs for People Exposed to Radiation as Part of Nuclear Weapons Testing Between 1945 and 1962, the United States ... involving about 200,000 people were conducted as part of many of these tests. ... several nuclear weapons plant sites were exposed to radiation and other ...

  1. Earth physicist describes US nuclear test monitoring system

    1986-01-01

    The U. S. capabilities to monitor underground nuclear weapons tests in the USSR was examined. American methods used in monitoring the underground nuclear tests are enumerated. The U. S. technical means of monitoring Solviet nuclear weapons testing, and whether it is possible to conduct tests that could not be detected by these means are examined. The worldwide seismic station network in 55 countries available to the U. S. for seismic detection and measurement of underground nuclear explosions, and also the systems of seismic research observatories in 15 countries and seismic grouping stations in 12 countries are outlined including the advanced computerized data processing capabilities of these facilities. The level of capability of the U. S. seismic system for monitoring nuclear tests, other, nonseismic means of monitoring, such as hydroacoustic and recording of effects in the atmosphere, ionosphere, and the Earth's magnetic field, are discussed.

  2. The struggle of the veterans of the French nuclear tests

    The question debated in this article concerns the demand of compensation and recognition of the impact on their health of nuclear tests. The military personnel that worked during nuclear tests in French Polynesia and the Sahara sites, but also the inhabitants of the atolls of Moruroa and Fangataufa equally in French Polynesia. An observatory of the veterans health has been created in order to improve the medical management of military personnel and former military personnel. An association 'Moruroa e tatou' contains the Polynesian former workers of the Nuclear tests of the Pacific and the association A.V.E.N. contains the veterans of nuclear tests. numerous examples are detailed. The question is tackled too for the consequences on health of the British nuclear tests, in Australia, Christmas Islands, and New Zealand. (N.C.)

  3. Testing the nuclear will of Japan

    Backer, David A.

    2007-01-01

    Increasing instability in the Northeast Asian region, decreasing faith in the U.S.-Japan security alliance, and the growing Chinese presence in the Northeast Asian region have caused Japanese politicians to revisit an issue that has been discussed three times in their history. The current issue is that, based on the above factors, Japan is once again considering whether or not the advantages of becoming a nuclear power outweigh the advantages of remaining a non-nuclear state. The purpose...

  4. Rover nuclear rocket engine program: Overview of rover engine tests

    Finseth, J. L.

    1991-01-01

    The results of nuclear rocket development activities from the inception of the ROVER program in 1955 through the termination of activities on January 5, 1973 are summarized. This report discusses the nuclear reactor test configurations (non cold flow) along with the nuclear furnace demonstrated during this time frame. Included in the report are brief descriptions of the propulsion systems, test objectives, accomplishments, technical issues, and relevant test results for the various reactor tests. Additionally, this document is specifically aimed at reporting performance data and their relationship to fuel element development with little or no emphasis on other (important) items.

  5. DPRK nuclear test. Statement by IAEA Director General

    Full text: IAEA Director General Mohamed ElBaradei deeply regrets, and expresses serious concern, about the reported carrying-out of a nuclear test earlier today by the Democratic People's Republic of Korea (DPRK). This reported nuclear test threatens the nuclear non-proliferation regime and creates serious security challenges not only for the East Asian region but also for the international community. The breaking of a de-facto global moratorium on nuclear explosive testing that has been in place for nearly a decade and the addition of a new State with nuclear weapon capacity is a clear setback to international commitments to move towards nuclear disarmament, said the Director General. Dr. ElBaradei further reiterates the urgent need - more than any time before - for establishing a legally binding universal ban on nuclear testing through the early entry-into-force of the Comprehensive Nuclear-Test Ban Treaty. Dr. ElBaradei continues to believe in the importance of finding a negotiated solution to the current situation regarding the DPRK nuclear issue. The Director General believes that resumption of dialogue between all concerned parties is indispensable and urgent. (IAEA)

  6. Recent irradiation tests for future nuclear system at HANARO

    The capsule at HANARO is a device that evaluates the irradiation effects of nuclear materials and fuels, which can reproduce the environment of nuclear power plants and accelerate to reach to the end of life condition. As the integrity assessment and the extension of lifetime of nuclear power plants are recently considered as important issues in Korea, the requirements for irradiation test are gradually being increased. The capacity and capability irradiation tests at HANARO are becoming important because Korea strives to develop SFR (Sodium-cooled Fast Reactor) and VHTR (Very High Temperature Reactor) among the future nuclear system and to export the research reactors and to develop the fusion reactor technology.

  7. Recent irradiation tests for future nuclear system at HANARO

    Cho, Man Soon; Choo, Kee Nam; Yang, Seong Woo; Park, Sang Jun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-05-15

    The capsule at HANARO is a device that evaluates the irradiation effects of nuclear materials and fuels, which can reproduce the environment of nuclear power plants and accelerate to reach to the end of life condition. As the integrity assessment and the extension of lifetime of nuclear power plants are recently considered as important issues in Korea, the requirements for irradiation test are gradually being increased. The capacity and capability irradiation tests at HANARO are becoming important because Korea strives to develop SFR (Sodium-cooled Fast Reactor) and VHTR (Very High Temperature Reactor) among the future nuclear system and to export the research reactors and to develop the fusion reactor technology.

  8. Nuclear analyses of Indian LLCB test blanket system in ITER

    Heading towards the Nuclear Fusion Reactor Program, India is developing Lead Lithium Ceramic Breeder (LLCB) tritium breeding blanket for its future fusion Reactor. A mock-up of the LLCB blanket is proposed to be tested in ITER equatorial port no. 2, to ensure the overall performance of blanket in reactor relevant nuclear fusion environment. Nuclear analyses play an important role in LLCB Test Blanket System development. It is required for tritium breeding estimation, thermal-hydraulic design, coolants process design, radio-active waste management, equipments maintenance and replacement strategies and nuclear safety. To predict the nuclear behaviour of LLCB test blanket module in ITER, nuclear responses like tritium production, nuclear heating, neutron fluxes and radiation damages are estimated. As a part of ITER machine, LLCB TBS has to follow certain nuclear shielding requirements i.e. shutdown dose rates should not exceed the defined limits in ITER premises (inside bio-shield ∼100 μSv/hr after 12 days cooling and outside bio-shield ∼10 μSv/hr after 1 day cooling). Hence nuclear analyses are performed to assess and optimize the shielding capability of LLCB TBS inside and outside bio-shield. To state the radio-activity level of LLCB TBS components which support the rad-waste and safety assessment, nuclear activation analyses are executed. Nuclear analyses of LLCB TBS are performed using ITER recommended nuclear analyses codes (i.e. MCNP, EASY), nuclear cross section data libraries (i.e. FENDL 2.1, EAF) and neutronic model (ITER C-lite v.1). The paper describes comprehensive nuclear performance of LLCB TBS in ITER. (author)

  9. Testing quantum correlations with nuclear probes

    We investigated the feasibility of quantum-correlation measurements in nuclear physics experiments. In the first approach, we measured spin correlations of singlet-spin (1S0) proton pairs, which were generated in 1H(d,2He) and 12C(d,2He) nuclear charge-exchange reactions. The experiment was optimized for a clean preparation of the 2He singlet state and offered a 2π detection geometry for both protons in the exit channel. Our results confirm the effectiveness of the setup for these studies, despite limitations of a small data sample recorded during the feasibility studies

  10. Application of bounding spectra to seismic design of piping based on the performance of above ground piping in power plants subjected to strong motion earthquakes

    This report extends the potential application of Bounding Spectra evaluation procedures, developed as part of the A-46 Unresolved Safety Issue applicable to seismic verification of in-situ electrical and mechanical equipment, to in-situ safety related piping in nuclear power plants. The report presents a summary of earthquake experience data which define the behavior of typical U.S. power plant piping subject to strong motion earthquakes. The report defines those piping system caveats which would assure the seismic adequacy of the piping systems which meet those caveats and whose seismic demand are within the bounding spectra input. Based on the observed behavior of piping in strong motion earthquakes, the report describes the capabilities of the piping system to carry seismic loads as a function of the type of connection (i.e. threaded versus welded). This report also discusses in some detail the basic causes and mechanisms for earthquake damages and failures to power plant piping systems

  11. Semipalatinsk nuclear test site: History of building and function

    A vast materials on history of Semipalatinsk nuclear test site creation and it building and function are presented. Authors with big reliability report one page of Kazakhstan's history. In steppe on naked place thousands of soldiers and officers, construct and military specialists have built the nuclear site on which during 40 years were conducting nuclear tests . Prolonged chronic radiation on population living near by site results to tragedy which is confessed by General Assembly of United Nations. In the book aspects of test site conversion and rehabilitation of injured population are considered. The book consists of introduction, three chapters and conclusion. The book is intended to wide circle of readers. (author)

  12. Nuclear weapons tests detectable worldwide by means of seismographic recording

    The site and intensity of nuclear weapons tests can be reliably determined by measurement and suitable interpretation of seismic waves. A seismic focus is up to 20 times larger than the destruction zone of a comparably strong explosion, so that a seismic event will last longer by one order of magnitude than an explosion. Nuclear weapons tests induce much more high-frequency vibrations than a seismic event, and a seismic event normally proceeds in a series of subsequent shocks. Diaphragms applied in the range 10 to 30 Hz considerably improve the signal-to-noise ratio of systems for the detection of nuclear weapons tests. (orig./DG)

  13. Fabrication Process of a Nuclear Fuel Test Rig in HANARO

    Hong, Jintae; Joung, Chang-Young; Ahn, Sung-Ho; Heo, Sung-Ho; Kim, Jin-Joo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    To evaluate the performance of newly developed PWR nuclear fuels, an adequate test rig installed in a pressure vessel of IPS, as a part of FTL (Fuel Test Loop) should be fabricated to meet the irradiation purposes. Generally, a nuclear fuel test rig is designed to measure the central temperature of a nuclear fuel pellet and the internal pressure of a fuel rod during an irradiation test. In special cases, it is also designed to measure the swelling or elongation of the fuel rod. The fabrication process of a nuclear fuel test rig that includes a detachable fuel rod assembly has been introduced in this study. Key techniques to fabricate a nuclear fuel test rig have been developed and used in fabricating a test rig mockup. Therefore, to fabricate a new test rig, the tooling of the components and making sub-assemblies that do not include nuclear fuels are out sourced, and the key assembly and sealing processes are carried out in the controlled area using the developed techniques.

  14. Fabrication Process of a Nuclear Fuel Test Rig in HANARO

    To evaluate the performance of newly developed PWR nuclear fuels, an adequate test rig installed in a pressure vessel of IPS, as a part of FTL (Fuel Test Loop) should be fabricated to meet the irradiation purposes. Generally, a nuclear fuel test rig is designed to measure the central temperature of a nuclear fuel pellet and the internal pressure of a fuel rod during an irradiation test. In special cases, it is also designed to measure the swelling or elongation of the fuel rod. The fabrication process of a nuclear fuel test rig that includes a detachable fuel rod assembly has been introduced in this study. Key techniques to fabricate a nuclear fuel test rig have been developed and used in fabricating a test rig mockup. Therefore, to fabricate a new test rig, the tooling of the components and making sub-assemblies that do not include nuclear fuels are out sourced, and the key assembly and sealing processes are carried out in the controlled area using the developed techniques

  15. Drought and root herbivory interact to alter the response of above-ground parasitoids to aphid infested plants and associated plant volatile signals

    Muhammad Tariq; Wright, Denis J.; Bruce, Toby J. A.; Staley, Joanna T.

    2013-01-01

    Multitrophic interactions are likely to be altered by climate change but there is little empirical evidence relating the responses of herbivores and parasitoids to abiotic factors. Here we investigated the effects of drought on an above/below-ground system comprising a generalist and a specialist aphid species (foliar herbivores), their parasitoids, and a dipteran species (root herbivore).We tested the hypotheses that: (1) high levels of drought stress and below-ground herbivory interact to r...

  16. Nuclear Weapons Tests and Environmental Consequences: A Global Perspective

    Prăvălie, Remus

    2014-01-01

    The beginning of the atomic age marked the outset of nuclear weapons testing, which is responsible for the radioactive contamination of a large number of sites worldwide. The paper aims to analyze nuclear weapons tests conducted in the second half of the twentieth century, highlighting the impact of radioactive pollution on the atmospheric, aquatic, and underground environments. Special attention was given to the concentration of main radioactive isotopes which were released, such as 14C, 137...

  17. Detailed Burnup Calculations for Testing Nuclear Data

    Leszczynski, F.

    2005-05-01

    A general method (MCQ) has been developed by introducing a microscopic burnup scheme that uses the Monte Carlo calculated fluxes and microscopic reaction rates of a complex system and a depletion code for burnup calculations as a basis for solving nuclide material balance equations for each spatial region in which the system is divided. Continuous energy-dependent cross-section libraries and full 3D geometry of the system can be input for the calculations. The resulting predictions for the system at successive burnup time steps are thus based on a calculation route where both geometry and cross sections are accurately represented, without geometry simplifications and with continuous energy data, providing an independent approach for benchmarking other methods and nuclear data of actinides, fission products, and other burnable absorbers. The main advantage of this method over the classical deterministic methods currently used is that the MCQ System is a direct 3D method without the limitations and errors introduced on the homogenization of geometry and condensation of energy of deterministic methods. The Monte Carlo and burnup codes adopted until now are the widely used MCNP and ORIGEN codes, but other codes can be used also. For using this method, there is need of a well-known set of nuclear data for isotopes involved in burnup chains, including burnable poisons, fission products, and actinides. For fixing the data to be included in this set, a study of the present status of nuclear data is performed, as part of the development of the MCQ method. This study begins with a review of the available cross-section data of isotopes involved in burnup chains for power and research nuclear reactors. The main data needs for burnup calculations are neutron cross sections, decay constants, branching ratios, fission energy, and yields. The present work includes results of selected experimental benchmarks and conclusions about the sensitivity of different sets of cross

  18. On the population dose around the Semipalatinsk nuclear test site

    Since 1949 the Semipalatinsk Nuclear Test Site (NTS) was extensively used by the former Soviet government as a testing range for atomic weapons. Atmospheric and underground tests were finally stopped in 1962 and 1989, respectively. The Ministry of the Russian Federation of Atomic Energy officially counts a total of 456 tests, including 116 atmospheric tests. The total yield of the nuclear explosions carried out was 6.3 Megatons equivalent with 6.7 PetaBq of 137Cs and 3.7 PetaBq of 90Sr being released into the athmosphere. Some of the athmospheric radioactive tests shielded plumes, which extended far beyond the outer borders of the NTS. Already the first Soviet atomic bomb test on August 29, 1949 due to unfavourable meteorological conditions affected the villages of Dolon and Moistik. Since 1995 joint investigations performed by the Research Centre Julich in cooperation with the Kazakh National Nuclear Centre in the region of the former nuclear test site near Semipalatinsk besides environmental measurents also involve the assessment of the current dose of the population at and around the test site in addition to the important retrospective determination of the dose of persons affected by the atmospheric tests

  19. Los Alamos studies of the Nevada test site facilities for the testing of nuclear rockets

    Hynes, Michael V.

    1993-01-01

    The topics are presented in viewgraph form and include the following: Nevada test site geographic location; location of NRDA facilities, area 25; assessment program plan; program goal, scope, and process -- the New Nuclear Rocket Program; nuclear rocket engine test facilities; EMAD Facility; summary of final assessment results; ETS-1 Facility; and facilities cost summary.

  20. The startup physics tests of Qinshan nuclear power plant

    The first startup physics tests of Qinshan Nuclear Power Company's 300 MW PWR are presented. These include the first initial criticality and low power physics tests. Testing items include critical boron concentration, control rod worth, boron worth, power distribution, temperature coefficient of moderator, minimum shutdown boron concentration, rod cluster shoot-out worth, etc. The results of tests verified that the basic requirements for the design and safety of the core have been satisfied

  1. Nuclebras' installations for performance tests of nuclear power plants components

    The reasons for Nuclebras' Nuclear Technology Development Center to implement a laboratory for supporting Brazilian manufactures, giving to them the means for performing functional tests of industrial products, are presented. A brief description of facilities under construction: the components Test Loop and Facility for Testing N.P.P. components under Accident conditions, and other already in operation, as well as its objectives and main technical characteristics. Some test results had already obtained are also presented. (Author)

  2. NUCLEBRAS' installations for tests of nuclear power plants components

    The reasons for NUCLEBRAS' Nuclear Technology Development Center to implement a laboratory for supporting Brazilian manufacturers, giving to them the means for performing functional tests of industrial products, are presented. A brief description of the facilities under construction: the Components Test Loop and the Facility for Testing N.P.P. Components under Accident Conditions, and of other already in operation, is given, as well as its objectives and main technical characteristics. Some test results already obtained are also presented. (Author)

  3. Performance tests for integral reactor nuclear fuel

    Sohn, Dong-Seong; Yim, Jeong-Sik; Lee, Chong-Tak; Kim, Han-Soo; Koo, Yang-Hyun; Lee, Byung-Ho; Cheon, Jin-Sik; Oh, Je-Yong

    2006-02-15

    An integral type reactor SMART plans to utilize metallic Zr-U fuel which is Zr-based alloy with 34{approx}38 wt% U. In order to verify the technologies for the design and manufacturing of the fuel and get a license, performance tests were carried out. Experimental Fuel Assembly (EFA) manufactured in KAERI is being successfully irradiated in the MIR reactor of RIAR from September 4 2004, and it has achieved burnup of 0.21 g/cc as of January 25 2006. Thermal properties of irradiated Zr-U fuel were measured. Up to the phase transformation temperature, thermal diffusivity increased linearly in proportion to temperature. However its dependence on the burnup was not significant. RIA tests with 4 unirradiated Zr-U fuel rods were performed in Kurchatov Institute to establish a safety criterion. In the case of the un-irradiated Zr-U fuel, the energy deposition during the control rod ejection accident should be less than 172 cal/g to prevent the failure accompanying fuel fragmentation and dispersal. Finally the irradiation tests of fuel rods have been performed at HANARO. The HITE-2 test was successfully completed up to a burnup of 0.31 g/cc. The HITE-3 test began in February 2004 and will be continued up to a target burnup of 0.6 g/cc.

  4. Performance tests for integral reactor nuclear fuel

    An integral type reactor SMART plans to utilize metallic Zr-U fuel which is Zr-based alloy with 34∼38 wt% U. In order to verify the technologies for the design and manufacturing of the fuel and get a license, performance tests were carried out. Experimental Fuel Assembly (EFA) manufactured in KAERI is being successfully irradiated in the MIR reactor of RIAR from September 4 2004, and it has achieved burnup of 0.21 g/cc as of January 25 2006. Thermal properties of irradiated Zr-U fuel were measured. Up to the phase transformation temperature, thermal diffusivity increased linearly in proportion to temperature. However its dependence on the burnup was not significant. RIA tests with 4 unirradiated Zr-U fuel rods were performed in Kurchatov Institute to establish a safety criterion. In the case of the un-irradiated Zr-U fuel, the energy deposition during the control rod ejection accident should be less than 172 cal/g to prevent the failure accompanying fuel fragmentation and dispersal. Finally the irradiation tests of fuel rods have been performed at HANARO. The HITE-2 test was successfully completed up to a burnup of 0.31 g/cc. The HITE-3 test began in February 2004 and will be continued up to a target burnup of 0.6 g/cc

  5. Seismic qualification tests of nuclear service pressure relief valves

    This paper reports on the pressure relief valves which provide an overpressure protection of vessels and piping in the nuclear power plant. A seismic qualification of these valves is essential to ensure their structural integrity and operability under earthquake and other dynamic conditions. Four spring loaded pressure relief valves were qualified by dynamic testing in response to a need for an overseas nuclear power plant construction. The test valves were actual production valves in 3/4 to 3 inch sizes and weighed approximately 11 to 110 lb. Each valve was subjected to triaxial random multifrequency testing (RMF), resonance search testing, sine beat testing and impact resonance search testing. Very briefly, the dynamic test conditions enveloped the specified required response spectra (RRS) and required input motion (RIM) vibratory conditions. Each valve input motion (RIM) vibratory conditions. Each valve was also tested to determine valve action, opening pressure and lift characteristics prior to, during, and after various dynamic tests. The valve leakage was also checked except during the dynamic testing. The test results showed very satisfactory operability of all four valves before, during and after the dynamic tests. These and other geometrically/functionally similar valves have also met the seismic qualification requirements of several other domestic and overseas nuclear power plants

  6. Proving test on the reliability for nuclear valves

    Since valves are the most common components, they could be the most frequent causes of troubles in nuclear power plants. This proving test, therefore, has an important meaning to examine and verify the reliability of various valves under simulating conditions of abnormal and transient operations of the nuclear power plant. The test was performed mainly for the various types and pressure ratings of valves which were used in the primary and secondary systems in BWR and PWR nuclear power plants and which had major operating or safety related functions in those nuclear power plants. The results of the proving test, confirmed for more than four years, showed relatively favourable performance of the tested valves. It is concluded that performances of valves including operability, seat sealing and structural integrity were proved under the thermal cycling, vibration and pipe reaction load conditions. Operating functions during and after accident such as loss of coolant accident were satisfactory. From these results, it was considered that the purpose of this proving test was satisfactorily fulfilled. Several data accumulated by the test would be useful to get better reliability if it was evaluated with the actually experienced data of valves in the nuclear power plants. (Nogami, K.)

  7. Verifying seismic design of nuclear reactors by testing. Volume 1: test plan

    This document sets forth recommendations for a verification program to test the ability of operational nuclear power plants to achieve safe shutdown immediately following a safe-shutdown earthquake. The purpose of the study is to develop a program plan to provide assurance by physical demonstration that nuclear power plants are earthquake resistant and to allow nuclear power plant operators to (1) decide whether tests should be conducted on their facilities, (2) specify the tests that should be performed, and (3) estimate the cost of the effort to complete the recommended test program

  8. OFF-SITE MONITORING FOR THE MIGHTY OAK NUCLEAR TEST

    After a nuclear explosives test, code name Mighty Oak, the tunnel leading to the test point became contaminated with radioactive debris. To re-enter and recover valuable equipment and data, the DOE purged the tunnel air using particulate and charcoal filters to minimize discharge...

  9. Task force for integral test of High Energy nuclear data

    Oyama, Yukio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-11-01

    According to completion of the JENDL-High Energy file for neutron nuclear cross sections up to 50 MeV, a task force for integral test of high energy nuclear data was organized to discuss a guide line for integral test activities. A status of existing differential and integral experiments and how to perform such a test were discussed in the task force. Here the purpose and outline of the task force is explained with some future problems raised in discussion among the task member. (author)

  10. Nuclear Test-Experimental Science: Annual report, fiscal year 1988

    Struble, G.L.; Donohue, M.L.; Bucciarelli, G.; Hymer, J.D.; Kirvel, R.D.; Middleton, C.; Prono, J.; Reid, S.; Strack, B. (eds.)

    1988-01-01

    Fiscal year 1988 has been a significant, rewarding, and exciting period for Lawrence Livermore National Laboratory's nuclear testing program. It was significant in that the Laboratory's new director chose to focus strongly on the program's activities and to commit to a revitalized emphasis on testing and the experimental science that underlies it. It was rewarding in that revolutionary new measurement techniques were fielded on recent important and highly complicated underground nuclear tests with truly incredible results. And it was exciting in that the sophisticated and fundamental problems of weapons science that are now being addressed experimentally are yielding new challenges and understanding in ways that stimulate and reward the brightest and best of scientists. During FY88 the program was reorganized to emphasize our commitment to experimental science. The name of the program was changed to reflect this commitment, becoming the Nuclear Test-Experimental Science (NTES) Program.

  11. The Nuclear Non-Proliferation Treaty and the Comprehensive Nuclear-Test-Ban Treaty, the relationship

    Graham, Thomas Jr. [7609 Glenbrook Rd., Bethesda, MD 20814 (United States)

    2014-05-09

    The Nuclear Non-Proliferation Treaty (NPT) is the most important international security arrangement that we have that is protecting the world community and this has been true for many years. But it did not happen by accident, it is a strategic bargain in which 184 states gave up the right forever to acquire the most powerful weapon ever created in exchange for a commitment from the five states allowed to keep nuclear weapons under the NPT (U.S., U.K., Russia, France and China), to share peaceful nuclear technology and to engage in disarmament negotiations aimed at the ultimate elimination of their nuclear stockpiles. The most important part of this is the comprehensive nuclear test ban (CTBT); the thinking by the 184 NPT non-nuclear weapon states was and is that they understand that the elimination of nuclear weapon stockpiles is a long way off, but at least the NPT nuclear weapon states could stop testing the weapons. The CTBT has been ratified by 161 states but by its terms it can only come into force if 44 nuclear potential states ratify; 36 have of the 44 have ratified it, the remaining eight include the United States and seven others, most of whom are in effect waiting for the United States. No state has tested a nuclear weapon-except for complete outlier North Korea-in 15 years. There appears to be no chance that the U.S. Senate will approve the CTBT for ratification in the foreseeable future, but the NPT may not survive without it. Perhaps it is time to consider an interim measure, for the UN Security Council to declare that any future nuclear weapon test any time, anywhere is a 'threat to peace and security', in effect a violation of international law, which in today's world it clearly would be.

  12. Space Nuclear Thermal Propulsion Nuclear Element Tests at Sandia National Laboratories

    Nuclear Element Tests (NET) are being performed as part of the U.S. Air Force Space Nuclear Thermal Propulsion (SNTP) Program to evaluate high performance fuel elements intended for use in future nuclear propulsion systems. The NET experiments are to be performed at the Sandia National Laboratories (SNL's) Annular Core Research Reactor (ACRR). Objectives of these experiments are to provide engineering validation and demonstration of critical-fuel-element-related technologies and an experimental data base to support analytical design methods for the SNTP Program. Currently, hardware for the first two fueled NET experiments has been fabricated, and cold flow tests have been accomplished with a representative set of hardware to assure the experimental capability to achieve test objectives in-reactor. Assembly of the first NET experiment to test a representative nuclear fuel element is in progress, and planned operational sequences have been defined

  13. Devices (manipulators) particularly for ultrasonic tests in nuclear power stations

    The manipulator devices for internal and external tests described in this article, were used successfully in the basic and repeat tests for nearly all West German, Swiss and Austrian nuclear power stations. For older reactors or for reactors originating from abroad one did not take sufficient account of the required accessibility to the test location in the configuration of the reactor pressure vessel, which led to complicated special manipulation devices. The handling of which at site requires a great deal of time. The more modern types of reactors are laid out so as to be easier to test and make a better manipulation test system and better test results possible. (orig./RW)

  14. Survey of hazardous materials used in nuclear testing

    Bryant, E.A.; Fabryka-Martin, J.

    1991-02-01

    The use of hazardous'' materials in routine underground nuclear tests at the Nevada Test Site has been reviewed. In addition the inventory of test yields, originally reported in 1976 has been updated. A trail down-hole inventory'' has been conducted for a selected test. The inorganic hazardous materials introduced during testing (with the exception of lead and the fissionable materials) produce an incremental change in the quantity of such materials already present in the geologic media surrounding the test points. 1 ref., 3 tabs.

  15. Importance of the quality control tests in nuclear medicine

    Full text: The acceptance of nuclear energy and its application by some part of the population are associated with the benefits brought by those activities and the guarantee that the incorporation of this technology will be strictly done according to the currently security norms. This project aims at presenting the Nuclear Medicine tests of control of quality models to assist the National Commission of Nuclear Energy Program of Regulatory Inspection (CNEN). The main aspects related with the radiological protection are discussed along the project and it is presented models that assist the Nuclear Medicine Service, in the matter of Radioprotection paying attention to the requirements of the Regulatory Inspection of CNEN. The fulfilment of such models shows, clearly, that they are fundamental for the radioprotection safety in the Nuclear Medicine Services. (author)

  16. Nuclear Test Ban: Converting Political Visions to Reality

    Suárez, Gerardo

    2010-05-01

    Negotiations to ban or at least restrict nuclear explosions began not long after the first test was conducted, in the Alamogordo desert of New Mexico on 16 July 1945. In August of that same year, the world witnessed the devastation of the Japanese cities of Hiroshima and Nagasaki and the horrifically destructive power that these weapons are capable of unleashing. Almost 50 years later, the long and tortuous road to negotiating a treaty that comprehensively bans nuclear explosions, whether for alleged peaceful purposes or for weapons development, culminated on 24 September 1996 when the Comprehensive Nuclear-Test-Ban Treaty (CTBT) was opened for signature. In a surge of enthusiasm, that first day the treaty was signed by more than 70 nations, including the five acknowledged nuclear powers. Addressing the United Nations General Assembly, U.S. President Bill Clinton described the CTBT as “the longest-sought, hardest-fought prize in the history of arms control.”

  17. Radioactive fallout in the southern hemisphere from nuclear weapons tests

    Fallout in the southern hemisphere, and its origins in the national programs of atmospheric nuclear weapons testing in both hemispheres, are reviewed. Of the 390 nuclear tests conducted in the atmosphere to date, 53 were carried out in the southern hemisphere and it is the second phase of these, between 1966 and 1974, that is seen to have been responsible for the main fallout of short-lived fission products in the southern hemisphere. In contrast to this, the programs of atmospheric nuclear testing in the northern hemisphere up to 1962 are shown to have been the main source of long-lived fission products in fallout in the southern hemisphere. The course followed by this contamination through the environment of the southern hemisphere is traced for the national programs of nuclear testing after 1962 taken separately (France, China) and for the earlier national programs taken together (U.S.S.R., U.S.A. and U.K.). The impact on populations in the southern hemisphere of fallout from atmospheric nuclear weapons tests to date is assessed

  18. A new role of proficiency testing in nuclear analytical work

    Heydorn, Kaj

    2008-01-01

    The most recent definition of measurement result requires a statement of uncertainty whenever results obtained by nuclear or other quantitative methods of analysis are reported. Proficiency testing (PT) therefore must include the ability of laboratories to present not only unbiased quantity values...... laboratory intercomparison of uranium isotopic ratios with very low reported uncertainties. In the paper this example is used to present the situation in the nuclear field....

  19. Nuclear commissioning of the NRU blowdown test facility

    The Blowdown Test Facility in the NRU reactor will be used to conduct all-effects experiments under postulated Loss-of-Coolant Accident and Severe Fuel Damage conditions. Experiments conducted in the BTF will provide information on the release, transport and deposition of fission products, and the thermal and mechanical behaviour of nuclear fuel under these conditions. This paper describes results from the nuclear commissioning experiment for the BTF. (2 refs., 4 figs.)

  20. On site inspection for nuclear test ban verirication

    P. D. Marschall

    1994-01-01

    The problem of verifying compliance with a nuclear test ban treaty is mainly a technical one. However the problem of detecting, locating and identifying nuclear explosions has, since the late 1950s, been intimately involved with the political problems associated with negotiating a treaty. In fact there are few other areas in which policy, diplomacy and science have been so interwoven. This paper attempts to illustrate how technology can. be applied to solve some of the political problems whic...

  1. Special tests of building structures of Dukovany nuclear power plant

    Two demanding safety tests for leaks are described applied to building structures of the Dukovany nuclear power plant. A hydrostatic leak test was conducted of tanks permanently or temporarily flooded, and an integral leak test was performed of the power plant sealed space. The objective was to show that the structures are leakproof in case of a hypothetical accident of the production unit. The hydrostatic leak test was performed by flooding the central part with 500 m3 of demineralized water. For the integral leak test the sealed space was pressurized with air to a value of 144 kPa. Defects inside the sealed space were continuously detected and removed. The lose of air in 24 hours was calculated. It is recommended that the experience gained should be used to work out standard requirements on leak tests of building structures of nuclear power plants. (Pu)

  2. Crash testing of nuclear fuel shipping containers

    In an attempt to understand the dynamics of extra severe transportation accidents and to evaluate state-of-the-art computational techniques for predicting the dynamic response of shipping casks involved in vehicular system crashes, the Environmental Control Technology Division of ERDA undertook a program with Sandia to investigate these areas. The program encompasses the following distinct major efforts. The first of these utilizes computational methods for predicting the effects of the accident environment and, subsequently, to calculate the damage incurred by a container as the result of such an accident. The second phase involves the testing of 1/8-scale models of transportation systems. Through the use of instrumentation and high-speed motion photography the accident environments and physical damage mechanisms are studied in detail. After correlating the results of these first two phases, a full scale event involving representative hardware is conducted. To date two of the three selected test scenarios have been completed. Results of the program to this point indicate that both computational techniques and scale modeling are viable engineering approaches to studying accident environments and physical damage to shipping casks

  3. Periodic testing of safety valves of nuclear facilities

    The report is concerned with the periodic performance testing of the pressure relief devices, i.e. safety and relief valves, used in nuclear power plants. The factors affecting the operation of safety and relief valves are described and the requirements and instructions presented in the literature for testing of safety and relief valves are reviewed. Moreover, some testing procedures and related equipment based on pertinent literature are presented. (30 refs., 11 figs., 4 tabs.)

  4. Recognition structure of semipalatinsk residents caused by nuclear explosion tests

    Authors' team of Hiroshima University and Scientific Research Institute of Radiation Medicine and Ecology (Kazakhstan) has been investigating the health state, exposure route, contents and mental effect of nuclear explosion tests of Semipalatinsk residents through their witness and questionnaire since 2002, to elucidate the humanistic damage of nuclear tests. Reported here is the recognition structure in the title statistically analyzed with use of frequently spoken words in the witness. The audit was performed in 2002-2007 to 994 residents who had experienced ground explosion tests during the period from 1949 to 1962 and were living in 26 villages near the old test site. Asked questions concerning nuclear tests involved such items as still unforgettable matters, dreadful events, regretting things, thought about the test, requests; and matters about themselves, their family, close friends and anything. The frequency of the test site-related words heard in the interview were analyzed with hierarchical clustering and multi-dimensional scaling with a statistic software R for computation and MeCab for morphological analysis. Residents' recognition was found to be of two structures of memory at explosion tests and anger/dissatisfaction/anxiety to the present state. The former contained the frequent words of mushroom cloud, flash, blast, ground tremble and outdoor evacuation, and the latter, mostly anxiety about health of themselves and family. Thus residents have had to be confronted with uneasiness of their health even 20 years after the closure of the test site. (T.T.)

  5. On-site tests on the nuclear power plants

    On-site tests and experiments are performed by EDF Research and Development Division on the nuclear power plants to assess the behaviour of major components submitted to thermal and vibratory solicitations. On-going studies deal with the qualification of new nuclear power plant standard and with the feedback of plants under operation. The tests, particularly the investigation tests, correspond to large investments and entail an important data volume which must ensure the continuity over a long period of the order of magnitude of the in-service plant life (around 40 years). This paper addresses the on-site experimental activities, describes the means to be used, and gives an example: the qualification of SG of new 1450 MW nuclear power plants. (author)

  6. Penetration Testing Model for Web sites Hosted in Nuclear Malaysia

    Nuclear Malaysia web sites has been very crucial in providing important and useful information and services to the clients as well as the users worldwide. Furthermore, a web site is important as it reflects the organisation image. To ensure the integrity of the content of web site, a study has been made and a penetration testing model has been implemented to test the security of several web sites hosted at Nuclear Malaysia for malicious attempts. This study will explain how the security was tested in the detailed condition and measured. The result determined the security level and the vulnerability of several web sites. This result is important for improving and hardening the security of web sites in Nuclear Malaysia. (author)

  7. Dynamic testing of pressure sensing lines in nuclear power plants

    Commercial nuclear power plants are equipped with instrumentation designed to detect unsafe conditions and, if required, to initiate protective action. The time elapsed between the realization of an unsafe condition and the initiation of protective action is known as the response time of the instrumentation involved. The US Nuclear Regulatory Commission has issued guidelines that advise periodic in situ response-time testing of safety-related instrumentation. No method is currently available for in situ response-time testing of pressure sensing lines (fluid-filled tubes connecting process to pressure transducer). A proposed method of doing just that has been investigated. While the proposed test (the burp test) was found to be impractical, a theoretical description of the sensing line led to the realization that it is probably not necessary to test the response time of sensing lines. Experimental observations backed up this conclusion

  8. Effluent treatment options for nuclear thermal propulsion system ground tests

    A variety of approaches for handling effluent from nuclear thermal propulsion system ground tests in an environmentally acceptable manner are discussed. The functional requirements of effluent treatment are defined and concept options are presented within the framework of these requirements. System concepts differ primarily in the choice of fission-product retention and waste handling concepts. The concept options considered range from closed cycle (venting the exhaust to a closed volume or recirculating the hydrogen in a closed loop) to open cycle (real time processing and venting of the effluent). This paper reviews the strengths and weaknesses of different methods to handle effluent from nuclear thermal propulsion system ground tests

  9. Handling effluent from nuclear thermal propulsion system ground tests

    A variety of approaches for handling effluent from nuclear thermal propulsion system ground tests in an environmentally acceptable manner are discussed. The functional requirements of effluent treatment are defined and concept options are presented within the framework of these requirements. System concepts differ primarily in the choice of fission-product retention and waste handling concepts. The concept options considered range from closed cycle (venting the exhaust to a closed volume or recirculating the hydrogen in a closed loop) to open cycle (real time processing and venting of the effluent). This paper reviews the different methods to handle effluent from nuclear thermal propulsion system ground tests

  10. Parity- and Time-Reversal Tests in Nuclear Physics

    Hertzog, David

    2013-01-01

    Nuclear physics tests of parity- and time-reversal invariance have both shaped the development of the Standard Model and provided key tests of its predictions. These studies now provide vital input in the search for physics beyond the Standard Model. We give a brief review of a few key experimental and theoretical developments in the history of this sub-field of nuclear physics as well as a short outlook, focusing on weak decays, parity-violation in electron scattering, and searches for permanent electric dipole moments of the neutron and neutral atoms.

  11. Parity- and Time-Reversal Tests in Nuclear Physics

    Hertzog, David; Ramsey-Musolf, Michael J.

    2012-01-01

    Nuclear physics tests of parity- and time-reversal invariance have both shaped the development of the Standard Model and provided key tests of its predictions. These studies now provide vital input in the search for physics beyond the Standard Model. We give a brief review of a few key experimental and theoretical developments in the history of this sub-field of nuclear physics as well as a short outlook, focusing on weak decays, parity-violation in electron scattering, and searches for perma...

  12. Capsule irradiation tests of nuclear materials in HANARO

    Several irradiation capsule (3 instrumented and 2 non-instrumented capsules) were designed, fabricated and successfully irradiated in HANARO CT and IR2 test holes since the first non-instrumented capsule of 96M-01K. Those capsule were designed for the irradiation of the RPV (Reactor Pressure Vessel) material used in Korean PWR nuclear reactors. Various instrumentation techniques including temperature measuring and monitoring, gas controlling, micro-heating and neutron fluence monitoring were also developed for the capsule irradiation system. Through the irradiation tests, the obtained experience and design data will be effectively applied to the capsule design of other nuclear materials. (author)

  13. The initial criticality and nuclear commissioning test program at HANARO

    The construction of the Korea Multipurpose Research Reactor - HANARO of 3MW, developed by Korea Atomic Energy Research Institute, was completed at the beginning of this year. The first fuel loading began on February 2 1995, and initial criticality was achieved on February 8, when the core had four 18-element assemblies and thirteen 36-element assemblies. The critical control rod position was 600.8 mm which represents excess reactivity of 0.71 $. Currently the nuclear commissioning test is on going under the zero power range. This paper describes the initial criticality approach of the HANARO, and its nuclear commissioning test program. (author)

  14. From Alamogordo to the Nuclear Test-Ban Treaty

    Friedlander, Michael

    2008-04-01

    After W.W.II., the U.S. continued its program for the development of nuclear weapons. Winds carried radioactive debris far beyond the Nevada test site, and these fission products were deposited by rain, to enter the human food chain. The isotopes of greatest concern were Sr90 and I131, that, after ingestion, become concentrated in bone and thyroid respectively. There was a growing public anxiety about possible heath hazards posed by radiation from this fallout. In March 1958, the Greater St. Louis Citizens' Committee for Nuclear Information (C.N.I.) was formed. Among the leaders of C.N.I. were E. U. Condon and Barry Commoner. The aim of C.N.I. was ``to collect and distribute in the widest possible manner information which the public requires to understand the present and future problems which arise from potential large-scale use of nuclear weapons in war; testing of nuclear weapons; and nonmilitary uses of nuclear energy.'' In accordance with its objectives, members of C.N.I. gave many nontechnical talks, where we described the various forms of radiation and what was then known about the biological effects of radiation. Some of our members testified at Congressional committee hearings. We published a newsletter, initially titled Nuclear Information, and later Scientist and Citizen. In this presentation, I will describe some of the activities of this idealistic organization.

  15. Lightning vulnerability of nuclear explosive test systems at the Nevada Test Site

    A task force chartered to evaluate the effects of lightning on nuclear explosives at the Nevada Test Site has made several recommendations intended to provide lightning-invulnerable test device systems. When these recommendations have been implemented, the systems will be tested using full-threat-level simulated lightning

  16. Nuclear tests of lepton number and CP nonconservation

    I will discuss two topics, double beta decay and time-reversal-odd nuclear moments, in which important questions of nuclear structure must be addressed. These problems are taken from a growing class of nuclear and atomic experiments in which the special properties of many-body systems are exploited to test properties of elementary particles. Nuclei can serve as filters for interactions by providing kinematic windows where only certain processes can occur and by isolating quantum numbers such as spin, isospin, and parity. In addition, the strengths of interesting interactions can be enhanced through the mixing of nearly degenerate levels in nuclei. However, the most important asset of nuclear and atomic experiments is their precision. For example, experiments searching for T-odd nuclear moments exploit techniques for measuring changes in atomic energies of 10-22 eV. Such precision techniques will play an increasingly important role in particle physics. In the discussion of double beta decay and T-odd nuclear moments it will become clear that important nuclear structure issues must be resolved in order to fully exploit the experimental results. During this talk I will highlight this aspect. 29 references

  17. Why nuclear power failed the market test in the UK

    The Conservative Party's manifesto for the general election of May 1987 contained two pledges of relevance to the UK electricity supply industry (ESI). These were to privatize the industry; and to continue to support the development of civil nuclear power in the private sector. As anticipated by some independent commentators, in the event these objectives proved incompatible. The costs of nuclear power have long been a vexed issue and UK nuclear costs have been higher than those in many other countries. While most of the UK ESI has now been privatized, nuclear generation remains in the public sector. This article seeks to explore the reasons for this fundamental and politically embarrassing policy reversal, a rarity under three successive Conservative administrations since 1979. It would be incorrect to argue that private ownership and nuclear power are inherently incompatible. Rather the specific - competitive - form of privatization proposed for the UK failed to provide sufficient guarantees for the London capital market. Thus, at least in this specific case, nuclear power failed the market test. The implications of this for the UK nuclear industry have been profound. As a result, the UK case has wider international lessons as the pressures for privatization, liberalization and greater cost transparency bear down upon electric utilities in other countries. (author)

  18. Special Nuclear Material Portal Monitoring at the Nevada Test Site

    Prior to April 2007, acceptance and performance testing of the various Special Nuclear Material (SNM) monitoring devices at the Nevada Test Site (NTS) was performed by the Radiological Health Instrumentation department. Calibration and performance testing on the PM-700 personnel portal monitor was performed, but there was no test program for the VM-250 vehicle portal monitor. The handheld SNM monitors, the TSA model 470B, were being calibrated annually, but there was no performance test program. In April of 2007, the Material Control and Accountability Manager volunteered to take over performance testing of all SNM portal monitors at NTS in order to strengthen the program and meet U.S. Department of Energy Order requirements. This paper will discuss the following activities associated with developing a performance testing program: changing the culture, learning the systems, developing and implementing procedures, troubleshooting and repair, validating the process, physical control of equipment, acquisition of new systems, and implementing the performance test program

  19. Nuclear waste repository transparency technology test bed demonstrations at WIPP

    Secretary of Energy, Bill Richardson, has stated that one of the nuclear waste legacy issues is ''The challenge of managing the fuel cycle's back end and assuring the safe use of nuclear power.'' Waste management (i.e., the back end) is a domestic and international issue that must be addressed. A key tool in gaining acceptance of nuclear waste repository technologies is transparency. Transparency provides information to outside parties for independent assessment of safety, security, and legitimate use of materials. Transparency is a combination of technologies and processes that apply to all elements of the development, operation, and closure of a repository system. A test bed for nuclear repository transparency technologies has been proposed to develop a broad-based set of concepts and strategies for transparency monitoring of nuclear materials at the back end of the fuel/weapons cycle. WIPP is the world's first complete geologic repository system for nuclear materials at the back end of the cycle. While it is understood that WIPP does not currently require this type of transparency, this repository has been proposed as realistic demonstration site to generate and test ideas, methods, and technologies about what transparency may entail at the back end of the nuclear materials cycle, and which could be applicable to other international repository developments. An integrated set of transparency demonstrations was developed and deployed during the summer, and fall of 1999 as a proof-of-concept of the repository transparency technology concept. These demonstrations also provided valuable experience and insight into the implementation of future transparency technology development and application. These demonstrations included: Container Monitoring Rocky Flats to WIPP; Underground Container Monitoring; Real-Time Radiation and Environmental Monitoring; Integrated level of confidence in the system and information provided. As the world's only operating deep geologic

  20. Dynamic testing of nuclear power plant structures: an evaluation

    Lawrence Livermore Laboratory (LLL) evaluated the applications of system identification techniques to the dynamic testing of nuclear power plant structures and subsystems. These experimental techniques involve exciting a structure and measuring, digitizing, and processing the time-history motions that result. The data can be compared to parameters calculated using finite element or other models of the test systems to validate the model and to verify the seismic analysis. This report summarizes work in three main areas: (1) analytical qualification of a set of computer programs developed at LLL to extract model parameters from the time histories; (2) examination of the feasibility of safely exciting nuclear power plant structures and accurately recording the resulting time-history motions; (3) study of how the model parameters that are extracted from the data be used best to evaluate structural integrity and analyze nuclear power plants

  1. Modeling and Simulation of a Nuclear Fuel Element Test Section

    Moran, Robert P.; Emrich, William

    2011-01-01

    "The Nuclear Thermal Rocket Element Environmental Simulator" test section closely simulates the internal operating conditions of a thermal nuclear rocket. The purpose of testing is to determine the ideal fuel rod characteristics for optimum thermal heat transfer to their hydrogen cooling/working fluid while still maintaining fuel rod structural integrity. Working fluid exhaust temperatures of up to 5,000 degrees Fahrenheit can be encountered. The exhaust gas is rendered inert and massively reduced in temperature for analysis using a combination of water cooling channels and cool N2 gas injectors in the H2-N2 mixer portion of the test section. An extensive thermal fluid analysis was performed in support of the engineering design of the H2-N2 mixer in order to determine the maximum "mass flow rate"-"operating temperature" curve of the fuel elements hydrogen exhaust gas based on the test facilities available cooling N2 mass flow rate as the limiting factor.

  2. Geologic surface effects of underground nuclear testing, Yucca Flat, Nevada Test Site, Nevada; TOPICAL

    This report presents a new Geographic Information System composite map of the geologic surface effects caused by underground nuclear testing in the Yucca Flat Physiographic Area of the Nevada Test Site, Nye County, Nevada. The Nevada Test Site (NTS) was established in 1951 as a continental location for testing nuclear devices (Allen and others, 1997, p.3). Originally known as the ''Nevada Proving Ground'', the NTS hosted a total of 928 nuclear detonations, of which 828 were conducted underground (U.S. Department of Energy, 1994). Three principal testing areas of the NTS were used: (1) Yucca Flat, (2) Pahute Mesa, and (3) Rainier Mesa including Aqueduct Mesa. Underground detonations at Yucca Flat and Pahute Mesa were typically emplaced in vertical drill holes, while others were tunnel emplacements. Of the three testing areas, Yucca Flat was the most extensively used, hosting 658 underground tests (747 detonations) located at 719 individual sites (Allen and others, 1997, p.3-4). Figure 1 shows the location of Yucca Flat and other testing areas of the NTS. Figure 2 shows the locations of underground nuclear detonation sites at Yucca Flat. Table 1 lists the number of underground nuclear detonations conducted, the number of borehole sites utilized, and the number of detonations mapped for surface effects at Yucca Flat by NTS Operational Area

  3. The consequences of underground nuclear testing in French Polynesia

    France began atmospheric nuclear testing at Mururoa and Fangataufa atolls in the South Pacific in July 1966. Following international protest, atmospheric testing ceased in August 1970. In late 1995, an International Geomechanical Commission (IGC) was created to assess the short- and long-term effects of underground nuclear testing on the stability and hydrology of Mururoa and Fangataufa. With the aid of its consultants, the Commission sought to develop its own understanding of the mechanics and consequences of the underground nuclear tests. It carried out extensive numerical analyses of shock wave effects, seismic wave propagation, slope stability and pre- and post-test hydrology. However, in its studies, the IGC was constrained to use the data made available to it by the French authorities. The Commission's report (International Geomechanical Commission 1998) has been submitted to the French Government. This article draws heavily on parts of that report. The Commission's observations and analyses show that there has been no apparent change, on the atoll scale, to the overall mechanical stability of either atoll as a consequence of the underground nuclear tests. The main observable consequences of the tests are underwater slope failures, open fractures on the rim surface and surface settlements. The fractures visible on the surface are generally associated with subsurface slope displacements and occur only in the carbonates. There is no evidence that slope failures or settlements have occurred in the underlying volcanics. There has been no significant change in the long-term (beyond 500 years) hydrology of either atoll. The IGC estimates that the long-term change in the natural groundwater flow will be no more than 1%. There are, however, significant short-term changes locally around the test sites, which are briefly outlined

  4. A nuclear power plant certification test plan and checklist

    Regulations within the nuclear industry are requiring that all reference plant simulators be certified prior to or during 1991. A certification test plan is essential to ensure that this goal is met. A description of each step in the certification process is provided in this paper, along with a checklist to help ensure completion of each item

  5. Prediction of ground motion from nuclear weapons tests at NTS

    Ground motion data from underground nuclear detonations during FY78 were added to data from earlier detonations; the data were used to formulate a tentative equation for predicting ground motion at the Nevada Test Site. Additional measurements to explore an unexplained seismic anomaly in Jackass Flats are described. Methods used in automatic processing of ground motion data are explained

  6. Drop testing of the Westinghouse fresh nuclear fuel package

    The Westinghouse Columbia Fuel Fabrication Facility has decided to develop and certify a new fresh fuel package design (type A, fissile) that has the capability to transport more highly enriched fuel than was previously possible. A prototype package was tested in support of the Safety Analysis Report of the Packaging (SARP). This paper provides detailed information on the tests and test results. A first prototype test was carried out at the STF, and the design did not give the safety margin that Westinghouse wanted for their containers. The data from the test were used to redesign the connection between the clamping frame and the pressure pad, and the tests were reinitiated. Three packages were then tested at the STF. All packages met the acceptance criteria and acceleration information was obtained that provided an indication of the behavior of the cradle and strongback which holds the fuel assemblies and nuclear poison in place. (J.P.N.)

  7. Overview of seismic reliability proof test of nuclear power facilities

    This report overviewed seismic reliability proof test of nuclear power facilities, which had been performed for 25 years until March 2004 to confirm seismic safety and safety margin of nuclear power facilities by seismic test of scale model equipment akin to full size using the Tadotsu Vibration Exciter. Test results were outlined to understand test objective, test model, earthquake input condition, test items and test results. Fifteen items were tested for verification tests of seismic reliability of reactor components or system against basic ground motion S1 and S2, and later validation of new technology (heavy components with energy absorbing support) and confirmation of functional limit of PCCV/RCCV and piping system. This report might contribute to understand safety function of important equipment against new basic earthquake ground motion Ss, and limit of strength/function or damage mode of equipment against earthquake beyond Ss, which were requested by 'new seismic design review guide' updated in September 2006 based on latest technical knowledge. (T. Tanaka)

  8. Guidelines for inservice testing at nuclear power plants

    Campbell, P.

    1995-04-01

    The staff of the U.S. Nuclear Regulatory Commission (NRC) gives licensees guidelines and recommendations for developing and implementing programs for the inservice testing of pumps and valves at commercial nuclear power plants. The staff discusses the regulations; the components to be included in an inservice testing program; and the preparation and content of cold shutdown justifications, refueling outage justifications, and requests for relief from the American Society of Mechanical Engineers Code requirements. The staff also gives specific guidance on relief acceptable to the NRC and advises licensees in the use of this information at their facilities. The staff discusses the revised standard technical specifications for the inservice testing program requirements and gives guidance on the process a licensee may follow upon finding an instance of noncompliance with the Code.

  9. Guidelines for inservice testing at nuclear power plants

    The staff of the U.S. Nuclear Regulatory Commission (NRC) gives licensees guidelines and recommendations for developing and implementing programs for the inservice testing of pumps and valves at commercial nuclear power plants. The staff discusses the regulations; the components to be included in an inservice testing program; and the preparation and content of cold shutdown justifications, refueling outage justifications, and requests for relief from the American Society of Mechanical Engineers Code requirements. The staff also gives specific guidance on relief acceptable to the NRC and advises licensees in the use of this information at their facilities. The staff discusses the revised standard technical specifications for the inservice testing program requirements and gives guidance on the process a licensee may follow upon finding an instance of noncompliance with the Code

  10. Nuclear performance analyses for HCPB test blanket modules in ITER

    Neutronic, shielding and activation analyses have been performed for recent design variants of the Helium Cooled Pebble Bed (HCPB) test blanket module (TBM) in ITER on the basis of 3D Monte Carlo calculations. The main objective has been to assess and optimise the nuclear performance of the HCPB test blanket modules in terms of the tritium generation, the nuclear heating and the radiation shielding and provide, among others, the data required for the engineering design of the test modules. The shielding efficiency of the TBM system was shown to be sufficient to allow access of work personnel to the port extension after a waiting time of 10 days after shut down as required by ITER. The activation analyses provided the afterheat and activation data for quality assured safety analyses assuming a representative irradiation scenario