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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Leaf sample detail, Feb2016-May2016, PA-SLZ, PA-PNM, PA-BCI: Panama

This data package contains details of the date, location, species and photographs of leaf samples collected on a monthly basis from Feb to May 2016 from Parque Natural Metropolitano (PA-PNM), Barro Colorado Island (PA-BCI) and Bosque Protector San Lorenzo (PA-SLZ) in Panama. Data from BCI only available for March. This data was collected as part of the 2016 El Niño-Southern Oscillation (ENSO) campaign. Included in this data package are an Excel file with data (2016ENSO_Panama_LeafSamples) and two Excel files with associated metadata. Sample photos are included in five zip files, organized by month and site. Also included is a Word document (Metadata_description_2016_ENSO_Panama) with details such as data collection methods, equipment used, and site information. Data to be used as a reference to linking related datasets including leaf water potential, leaf spectra, LMA, gas exchange and leaf chemistry (CHN, NSC). Most leaves were sampled from sunlit canopy trees. VERSION 2 update. The identification of a species from the PNM site has been corrected as follows: the identification of the tree initially identified as Pseudosamanea guachapele (ALBIED) has been revised to Albizia adinocephala (ALBIAD). The updated data package includes revised data, metadata and protocol documents updated to reflect this change.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Diurnal leaf gas exchange survey, Feb2016-May2016, PA-SLZ, PA-PNM: Panama

This data package contains the results of a diurnal leaf gas exchange survey measured on sunlit canopy trees within the NGEE Tropics sites Parque Natural Metropolitano (PA-PNM) and Bosque Protector San Lorenzo (PA-SLZ) in Panama. Measurements were taken on a monthly basis from February to May of 2016. This data was collected as part of the 2016 El Niño-Southern Oscillation (ENSO) campaign. Included in this data package are two Excel files with data (2016ENSO_Panama_DiurnalGasEx, 2016ENSO_Panama_AreaCorrections) and additional Excel files with associated metadata. Also included is a Word document (Metadata_description_2016_ENSO_Panama) with details such as data collection methods, equipment used, and site information. See related datasets for further sample details, leaf water potential, LMA, leaf spectra, other gas exchange and leaf chemistry. VERSION 2 update. The identification of a species from the PNM site has been corrected as follows: the identification of the tree initially identified as Pseudosamanea guachapele (ALBIED) has been revised to Albizia adinocephala (ALBIAD). The updated data package includes revised data, metadata and protocol documents updated to reflect this change.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Leaf mass area, Feb2016-May2016, PA-SLZ, PA-PNM, PA-BCI: Panama

This data package contains leaf mass data per unit area measured on a monthly basis from February to April, 2016, at the Bosque Protector San Lorenzo (PA-SLZ) and Parque Natural Metropolitano (PA-PNM) sites in Panama. Data from the Barro Colorado Island (PA-BCI) site are only available for March. This data was collected as part of the 2016 El Niño-Southern Oscillation (ENSO) campaign. Included in this data package are an Excel file with data (2016ENSO_Panama_LMA1) and two Excel files with associated metadata. Also included is a Word document (Metadata_description_2016_ENSO_Panama) with details such as data collection methods, equipment used, and site information. See related datasets for further sample details, leaf water potential, leaf spectra, gas exchange and leaf chemistry. VERSION 2 update. The identification of a species from the PNM site has been corrected as follows: the identification of the tree initially identified as Pseudosamanea guachapele (ALBIED) has been revised to Albizia adinocephala (ALBIAD). The updated data package includes revised data, metadata and protocol documents updated to reflect this change.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Leaf spectra, Feb2016-April2016, PA-SLZ, PA-PNM, PA-BCI: Panama

This data package contains leaf spectra data measured on a monthly basis from February to April, 2016. Measurements were taken at the Bosque Protector San Lorenzo (SLZ), Barro Colorado Island (BCI) and Parque Natural Metropolitano (PNM) NGEE Tropics sites in Panama. Data from the BCI site are only available for March, 2016. Within the attached zip file are PDF manuals for instruments used, a guide to data collection protocol, and metadata files, including a PDF containing metadata for the 2016 ENSO gas exchange campaign. Also included is an additional zip file "2016_ENSO_BNL_Leaf_Spectra_Archive.zip" with data in .csv format organized by site. This data was collected as part of the 2016 ENSO campaign. See related datasets (existing and future) for further sample details, leaf water potential data, LMA, and gas exchange and leaf chemistry data. VERSION 2 update. The identification of a species from the PNM site has been corrected as follows: the identification of the tree initially identified as Pseudosamanea guachapele (ALBIED) has been revised to Albizia adinocephala (ALBIAD). The updated data package includes revised data, metadata and protocol documents updated to reflect this change.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Pantropical tropical tree xylem hydraulic functional traits, 1991 - 2013

This data package contains xylem hydraulic properties data, both newly extracted from publications plus tropics-specific data extracted from the "Xylem Functional Traits Database" (Choat et al., 2012; Gleason et al., 2016), which is available on TRY (www.try-db.org). Choat, B., Jansen, S., et al: Global convergence in the vulnerability of forests to drought, Nature, doi: 10.1038/nature11688, 2012. 2012. Gleason, S. M., Westoby, M., Jansen, S., Choat, B., et al.: Weak tradeoff between xylem safety and xylem-specific hydraulic efficiency across the world's woody plant species, New Phytologist, 209, 123-136, 2016. Measurements include xylem hydraulic conductivity per unit sapwood (Ks) and per unit leaf (Kl) area, water potential at 12%, 50%, and 88% loss of conductivity (P12, P50, and P88, respectively), leaf mass per area, wood density, and maximum rate of photosynthesis. Data span both natural tropical forests and plantations and rainfall gradients from deciduous dry tropical forests to everwet tropical forests, and come from countries all across the pantropics. Data is included in the attached zip file as three CSV files.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Leaf structural and chemical traits, and BNL field campaign sample details, San Lorenzo, Panama, 2020

This data package includes leaf traits, canopy traits and sample details for leaves from 71 species sampled from the San Lorenzo forest canopy crane site, Panama (PA-SLZ) during the BNL field campaign in January to March 2020. Each leaf sample is described with species, phenological stage and location within vertical canopy profiles. Leaf area index (LAI) and height is presented for each canopy profile location. Leaf mass per area (LMA), leaf water content (LWC) and leaf carbon and nitrogen content are included for a subset of the samples. This data package includes sample details, processed data for leaf traits and LAI (*.csv), LAI raw data (compressed as *.zip) and digital camera images (*.jpg, compressed as *.zip) of the leaf samples. Metadata files include data descriptions (_dd.csv) for tabular data, a list of all species sampled during the campaign (*.csv) and a detailed description of the field campaign protocol and methods (*.pdf). See related datasets for leaf gas exchange, leaf water potential and leaf spectral measurements made on the samples described here.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Functional trait data for 11 canopy tree species in the control and drought treatments at AU-DRO (2018-2019)

This data package contains foliar abscisic acid levels, xylem anatomy, foliar d13C, leaf mass per area, leaf water potentials, non-structural carbohydrates, and pressure volume curve traits for 11 canopy tree species in the control and drought treatments at the Daintree Rainforest Observatory in Queensland, Australia (AU-DRO). Data were collected at the end of the dry season (Nov 2018) and end of the wet season (May 2019). The species included in the dataset are: Castanospermum australe, Cleistanthus myrianthus, Cryptocarya mackinnoniana, Dysoxylum papuanum, Elaeocarpus angustifolius (Elaeocarpus grandis), Endiandra microneura, Mallotus paniculatus, Myristica globosa, Rockinghamia angustifolia, Synima cordierorum, Syzygium spp. These data correspond to the previously archived dataset “Leaf gas exchange data, Nov 2018 and May 2019, Daintree Rainforest, Australia. NGEE-Tropics Data Archive” (DOI: 10.15486/ngt/1773854).

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Leaf C and N content, Feb2016-May2016, PA-SLZ, PA-PNM, PA-BCI: Panama

This dataset contains carbon, hydrogen and nitrogen content data of 33 tree species collected from February to May 2016 at the NGEE-Tropics Bosque Protector San Lorenzo (PA-SLZ) and Parque Natural Metropolitano (PA-PNM) sites in Panama. Data from Barro Colorado Island (PA-BCI) is only available for March 2016. This data was collected as part of the 2016 ENSO campaign. See related datasets for further sample details, leaf water potential, leaf spectra, gas exchange and leaf mass per area (LMA). Most leaves were sampled from sunlit canopy trees. VERSION 2 update. The identification of a species from the PNM site has been corrected as follows: the identification of the tree initially identified as Pseudosamanea guachapele (ALBIED) has been revised to Albizia adinocephala (ALBIAD). The updated data package includes revised data, metadata and protocol documents updated to reflect this change.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Leaf C and N content by leaf age, Feb2017, PA-SLZ: Panama

This dataset contains carbon, hydrogen and nitrogen content measurements of sunlit canopy leaves of Apeiba membranacea (APEIME), Guatteria dumetorum (GUATDU), Miconia borealis (MICOBO), Terminalia amazonia (TERMAM), Virola multiflora (VIROSP) and Vochysia ferruginea (VOCHFE) species. Data was collected from the NGEE-Tropics Bosque Protector San Lorenzo (PA-SLZ) site in Panama in February of 2017 as part of the 2017 Brookhaven National Lab–Smithsonian Tropical Research Institute leaf traits by age campaign. A PDF with full sapling protocol is included in this dataset, along with metadata files in Excel file format. Data is in both CSV (Panama2017_CHN.csv) and Excel file formats. See related datasets for further sample details, leaf spectra, sap flow, leaf water potential, leaf mass per area (LMA), and gas exchange measurements.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2026

Department of Transportation PHMSA Aerosol Spray Project: Phase-0

This report discusses the work conducted at Sandia National Laboratories during the preliminary phase (Phase-0) of the Department of Transportation (DOT) Pipeline and Hazardous Materials Safety Administration (PHMSA) project tasked to better understand what happens to a high-pressure liquid canister or vessel during a fire in which an accidental instantaneous release occurs. Phase 0 had two main objects: (1) to establish a methodology for the high temperature and pressure spray vessel release and (2) to characterize the spray droplet formation. For this test series, diagnostic equipment such as the Malvern Spraytec, high-speed photometric cameras, pencil gauges, and thermocouples were used. Additionally, the effect of surface tension on the particle size distribution was evaluated with 1-liter of distilled water and with the same including the addition of 0.5% soap/water mixture. Results from this effort indicated that the plume formed from the instantaneous release in all conditions primarily included two distinct particle size distributions including 217-312µm and 0.53µm on average. Soapy water formed a higher concentration of smaller mist (0.53µm) than distilled water, potentially due to decreased surface tension with the added surfactant. Though results showed good correlation to certain particle size distributions it is encouraged to conduct additional tests like this with a wider range of liquids with different properties, which could affect the overall particle size distribution when released.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Lianas and Trees From a Seasonally Dry and a Wet Tropical Forest Did Not Differ in Embolism Resistance but Did Differ in Xylem Anatomical Traits in the Dry Forest

One of the most prominent changes in neotropical forests has been the increase in abundance and size of lianas. Studies suggest that lianas have more acquisitive strategies than trees, which could allow them to take advantage of water more effectively when it is available in water-limited forests, but few studies compared across growth form (i.e., lianas vs. trees) and forest type (i.e., wet vs. seasonally dry). We measured hydraulic and anatomical traits of co-occurring lianas and trees that convey drought resistance (xylem embolism resistance and intervessel pit membranes) and water transport capacity (xylem vessel diameter and density) in a seasonally dry and a wet evergreen tropical forest to address: (1) Are there differences between vulnerability to embolisms (P 50 —water potential at 50% loss of hydraulic conductivity) and hydraulic safety margins (HSM) across growth form and forest type? (2) How do vessel diameter and density vary across growth form and forest type? (3) Are there differences in xylem intervessel pit membrane thickness across growth form and forest type and does it predict xylem embolism vulnerability in trees and lianas? We examined hydraulic and xylem anatomical traits of 32 species—eight lianas and eight trees in each forest type. We found no difference in P 50 and HSMs between lianas and trees and between the wetter and drier forest. Dry forest lianas had 81% greater maximum vessel diameter and 125% greater range in vessel diameter sizes than dry forest trees but, there was no significant difference between life forms in the wet forest. Dry forest species had 50% greater vessel density and 30% greater maximum pit membrane thickness than wet forest ones. Maximum pit membrane thickness was correlated to P 50 and HSMs. The main difference between lianas and trees occurred in the dry forest, where lianas had larger maximum xylem vessel size than trees, implying that they have proportionally greater hydraulic conductive capacity than the trees in seasonal forests.

Smith-Martin, Chris M.↗
NASA NTRS1981

A project to evaluate moisture stress and phenological factors in corn and soybean areas of southwestern and south-central Minnesota

The capability of aerial color infrared photography for identifying and locating soilscapes most susceptible to drought development or those having different soil drainages was evaluated. Although west central and southwestern Minnesota had a significant precipitation deficit during the 1980 crop season, indications of plant stress were not observed either from ground observation or through interpretation of imagery at the selected sampling sites. Well-drained soil was more depleted during the "maximium green peak" period than the poorly drained soil. The recharge was more evident on the poorly drained site in the fall. Measurements of leaf water potential and leaf temperature for corn and soybean leaves were made by multispectral band scanner and recorded for analysis.

Rust, R. H.↗
NASA NTRS1983

Simulating spatial and temporal variation of corn canopy temperature during an irrigation cycle

The canopy air temperature difference (delta T) which provides an index for scheduling irrigation was examined. The Monteith transpiration equation was combined with both uptake from a single layered root zone and change in internal storage of the plant and the continuity equation for water flux in the soil plant atmosphere system was solved. The model indicates that both daily total transpiration and soil induced depression of plant water potential may be inferred from mid-day delta T. It is suggested that for the soil plant weather data used in the simulation, either a mid day spatial variability of about 0.8K in canopy temperatures or a field averaged delta T of 2 to 4K may be a suitable criterion for irrigation scheduling.

Choudhury, B. J.↗
NASA NTRS1985

Mechanical Stress Regulation of Plant Growth and Development

Growth dynamics analysis was used to determine to what extent the seismic stress induced reduction in photosynthetic productivity in shaken soybeans was due to less photosynthetic surface, and to what extent to lower efficiency of assimulation. Seismic stress reduces shoot transpiration rate 17% and 15% during the first and second 45 minute periods following a given treatment. Shaken plants also had a 36% greater leaf water potential 30 minutes after treatment. Continuous measurement of whole plant photosynthetic rate shows that a decline in CO2 fixation began within seconds after the onset of shaking treatment and continued to decline to 16% less than that of controls 20 minutes after shaking, after which gradual recovery of photosynthesis begins. Photosynthetic assimilation recovered completely before the next treatment 5 hours later. The transitory decrease in photosynthetic rate was due entirely to a two fold increase in stomatal resistance to CO2 by the abaxial leaf surface. Mesophyll resistance was not significantly affected by periodic seismic treatment. Temporary stomatal aperture reduction and decreased CO2 fixation are responsible for the lower dry weight of seismic stressed plants growing in a controlled environment.

Mitchell, C. A.↗
NASA NTRS1987

Remote sensing of leaf water status

Relative water content (RWC) measurements were made concurrently with spectral reflectance measurements from individual snapbean leaves. The relationships between spectra and RWC were described using second order polynomial equations. The middle infrared bands most sensitive to changes in leaf RWC also had the highest water absorption coefficients, as published by Curcio Petty (1951). The relationship between reflectance at 2100nm and total water potential for a single leaf was found to be linear.

Ripple, William J.↗
NASA NTRS1988

Estimating soil water evaporation using radar measurements

Field studies were conducted to evaluate the application of radar reflectivity as compared with the shortwave reflectivity (albedo) used in the Idso-Jackson equation for the estimation of daily evaporation under overcast sky and subhumid climatic conditions. Soil water content, water potential, shortwave and radar reflectivity, and soil and air temperatures were monitored during three soil drying cycles. The data from each cycle were used to calculate daily evaporation from the Idso-Jackson equation and from two other standard methods, the modified Penman and plane of zero-flux. All three methods resulted in similar estimates of evaporation under clear sky conditions; however, under overcast sky conditions, evaporation fluxes computed from the Idso-Jackson equation were consistently lower than the other two methods. The shortwave albedo values in the Idso-Jackson equation were then replaced with radar reflectivities and a new set of total daily evaporation fluxes were calculated. This resulted in a significant improvement in computed soil evaporation fluxes from the Idso-Jackson equation, and a better agreement between the three methods under overcast sky conditions.

Sadeghi, Ali M.↗
NASA NTRS1990

Components of surface energy balance in a temperate grassland ecosystem

Eddy correlation measurements of moisture, heat, and momentum fluxes were made at a tall grassland site in Kansas during the First International Satellite Land Surface Climatology Project Field Experiment. The fluxes, stomatal conductance, and leaf water potential of three grass species are reported. The species are big bluestem, indiangrass, and switchgrass. The daily and seasonal variation in the components of the surface energy balance and the aerodynamic and canopy surface conductances for prairie vegetation are examined.

Kim, Joon↗