scholarly journals In situ measurements of winter wheat diurnal changes in photosynthesis and environmental factors reveal new insight into photosynthesis improvement by super-high-yield cultivation

2021 ◽  
Vol 20 (2) ◽  
pp. 527-539
Author(s):  
Ming-yang MA ◽  
Yang LIU ◽  
Yao-wen ZHANG ◽  
Wei-long QIN ◽  
Zhi-min WANG ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Winter Wheat ◽  
In Situ Measurements ◽  
High Yield ◽  
Diurnal Changes ◽  
Insight Into

scholarly journals The First Evaluation of Formaldehyde Column Observations by Pandora Spectrometers during the KORUS-AQ Field Study

2018 ◽  
Author(s):  
Elena Spinei ◽  
Andrew Whitehill ◽  
Alan Fried ◽  
Martin Tiefengraber ◽  
Travis N. Knepp ◽  
...  
Keyword(s):  
Field Study ◽  
Mixed Layer ◽  
In Situ Measurements ◽  
Rural Site ◽  
Forest Site ◽  
Diurnal Changes ◽  
Layer Height ◽  
Mixed Layer Height ◽  
Total Column

Abstract. The KORUS-AQ field study conducted during May–June 2016 offered the first opportunity to evaluate direct-sun observations of formaldehyde (HCHO) total column densities with improved Pandora spectrometer instruments. The measurements highlighted in this work were conducted both in the Seoul megacity area at the Olympic Park site (latitude: 37.5232° N, longitude: 127.1260° E, 26 m a.s.l.) and at a nearby rural site downwind of the city at the Mount Taehwa Research Forest site (latitude: 37.3123° N, longitude: 127.3106° E, 160 m a.s.l.). Evaluation of these measurements was made possible by concurrent ground-based in situ observations of HCHO at both sites as well as overflight by the NASA DC-8 research aircraft. The flights provided in situ measurements of HCHO to characterize its vertical distribution in the lower troposphere (0–5 km). Diurnal variation in HCHO total column densities followed the same pattern at both sites, with the minimum daily values typically observed between 6:00–7:00 local time, gradually increasing to a maximum between 13:00 and 17:00 before decreasing into the evening. Pandora vertical column densities were compared with those derived from the DC-8 HCHO in-situ measured profiles augmented with in-situ surface concentrations below the lowest altitude of the DC-8 in proximity to the ground sites. A comparison between 49 column densities measured by Pandora versus aircraft integrated in-situ data showed that Pandora values were larger by 16 % (intercept = 0.22 DU, R2 =  0.68). Pandora HCHO columns were also compared with columns calculated from the surface in-situ measurements over Olympic Park by assuming a well-mixed lower atmosphere up to a ceilometer measured mixed-layer height (MLH) and various assumptions about the small residual HCHO amounts in the free troposphere up to the tropopause. The best comparison (slope = 1.03 ± 0.03, intercept = 0.29 ± 0.02 DU and R2 of 0.78 ± 0.02) was achieved assuming equal mixing within ceilometer measured MLH combined with an exponential profile shape. These results suggest that diurnal changes in HCHO surface concentrations can be reasonably estimated from the Pandora total column and information on the mixed-layer height. More work is needed to understand the bias in the intercept and the slope relative to columns derived from the in-situ aircraft and surface measurements.

scholarly journals In-situ measurements of oxygen, carbon monoxide and greenhouse gases from Ochsenkopf tall tower in Germany

2009 ◽  
Vol 2 (2) ◽  
pp. 573-591 ◽  
Author(s):  
R. L. Thompson ◽  
A. C. Manning ◽  
E. Gloor ◽  
U. Schultz ◽  
T. Seifert ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Growth Rate ◽  
Fossil Fuels ◽  
In Situ Measurements ◽  
Seasonal Cycles ◽  
Diurnal Changes ◽  
Diurnal Variability ◽  
Annual Variations ◽  
Mixing Ratios

Abstract. We present 2.5 years (from June 2006 to December 2008) of in-situ measurements of CO2, O2, CH4, CO, N2O and SF6 mixing ratios sampled from 23, 90 and 163 m above ground on the Ochsenkopf tower in the Fichtelgebirge range, Germany (50°01'49" N, 11°48'30" E, 1022 m a.s.l.). In addition to the in-situ measurements, flask samples are taken at Ochsenkopf at approximately weekly intervals and are subsequently analysed for the mixing ratios of the same species, as well as H2, and the stable isotopes, δ13C, δ18O in CO2. The in-situ measurements of CO2 and O2 from 23 m show substantial diurnal variations that are modulated by biospheric fluxes, combustion of fossil fuels, and by diurnal changes in the planetary boundary layer height. Measurements from 163 m exhibit only very weak diurnal variability, as this height (1185 m a.s.l.) is generally above the nocturnal boundary layer. CH4, CO, N2O and SF6 show little diurnal variation even at 23 m owing to the absence of any significant diurnal change in the fluxes and the absence of any strong local sources or sinks. From the in-situ record, the seasonal cycles of the gas species have been characterized and the multi-annual trends determined. Because the record is short, the calculation of the trend is sensitive to inter-annual variations in the amplitudes of the seasonal cycles. However, for CH4 a significant change in the growth-rate was detected for 2006.5–2008.5 as compared with the global mean from 1999 to 2006 and is consistent with other recent observations of a renewed increasing global growth rate in CH4 since the beginning of 2007.

In Situ Measurements of Through-Plane, Ionic Potential Distributions in Porous Electrodes

2010 ◽  
Author(s):  
Katherine C. Hess ◽  
William K. Epting ◽  
Shawn Litster
Keyword(s):  
Polymer Electrolyte Membrane ◽  
Porous Electrode ◽  
Catalyst Layer ◽  
In Situ Measurements ◽  
Porous Electrodes ◽  
Ionic Potential ◽  
Electrolyte Membrane ◽  
Insight Into

We present a novel apparatus for gathering in situ measurements of through-plane, ionic potential distributions in the porous electrodes of a polymer electrolyte membrane (PEM) fuel cell. Our diagnostic method uses a micro-structured electrode scaffold (MES) that is comprised of alternating layers of insulating and sensing materials into which a 100 μm diameter hole is micro-milled and then filled with catalyst ink. Using the MES, we performed a polarization curve experiment where the ionic potential was measured within a 50 μm thick catalyst layer at 8 and 24 μm from membrane. Our results show that there are significant ionic potential variations within the electrode. Such data is valuable in the electrochemical characterization of electrodes and catalysts. The MES potential measurements also provide insight into reaction distributions across the thickness of the electrode, which is valuable in the validation of porous electrode models.

scholarly journals The first evaluation of formaldehyde column observations by improved Pandora spectrometers during the KORUS-AQ field study

2018 ◽  
Vol 11 (9) ◽  
pp. 4943-4961 ◽  
Author(s):  
Elena Spinei ◽  
Andrew Whitehill ◽  
Alan Fried ◽  
Martin Tiefengraber ◽  
Travis N. Knepp ◽  
...  
Keyword(s):  
Mixed Layer ◽  
Lower Troposphere ◽  
In Situ Measurements ◽  
Rural Site ◽  
Forest Site ◽  
Diurnal Changes ◽  
Layer Height ◽  
Mixed Layer Height ◽  
Total Column

Abstract. The Korea–United States Air Quality Study (KORUS-AQ) conducted during May–June 2016 offered the first opportunity to evaluate direct-sun observations of formaldehyde (HCHO) total column densities with improved Pandora spectrometer instruments. The measurements highlighted in this work were conducted both in the Seoul megacity area at the Olympic Park site (37.5232∘ N, 27.1260∘ E; 26 m a.s.l.) and at a nearby rural site downwind of the city at the Mount Taehwa research forest site (37.3123∘ N, 127.3106∘ E; 160 m a.s.l.). Evaluation of these measurements was made possible by concurrent ground-based in situ observations of HCHO at both sites as well as overflight by the NASA DC-8 research aircraft. The flights provided in situ measurements of HCHO to characterize its vertical distribution in the lower troposphere (0–5 km). Diurnal variation in HCHO total column densities followed the same pattern at both sites, with the minimum daily values typically observed between 6:00 and 7:00 local time, gradually increasing to a maximum between 13:00 and 17:00 before decreasing into the evening. Pandora vertical column densities were compared with those derived from the DC-8 HCHO in situ measured profiles augmented with in situ surface concentrations below the lowest altitude of the DC-8 in proximity to the ground sites. A comparison between 49 column densities measured by Pandora vs. aircraft-integrated in situ data showed that Pandora values were larger by 16 % with a constant offset of 0.22 DU (Dobson units; R2=0.68). Pandora HCHO columns were also compared with columns calculated from the surface in situ measurements over Olympic Park by assuming a well-mixed lower atmosphere up to a ceilometer-measured mixed-layer height (MLH) and various assumptions about the small residual HCHO amounts in the free troposphere up to the tropopause. The best comparison (slope =1.03±0.03; intercept =0.29±0.02 DU; and R2=0.78±0.02) was achieved assuming equal mixing within ceilometer-measured MLH combined with an exponential profile shape. These results suggest that diurnal changes in HCHO surface concentrations can be reasonably estimated from the Pandora total column and information on the mixed-layer height. More work is needed to understand the bias in the intercept and the slope relative to columns derived from the in situ aircraft and surface measurements.

scholarly journals In-situ measurements of oxygen, carbon monoxide and greenhouse gases from Ochsenkopf tall tower in Germany

2009 ◽  
Vol 2 (3) ◽  
pp. 1247-1291 ◽  
Author(s):  
R. L. Thompson ◽  
A. C. Manning ◽  
E. Gloor ◽  
U. Schultz ◽  
T. Seifert ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Growth Rate ◽  
Fossil Fuels ◽  
In Situ Measurements ◽  
Seasonal Cycles ◽  
Diurnal Changes ◽  
Diurnal Variability ◽  
Annual Variations ◽  
Mixing Ratios

Abstract. We present 2.5 years of in-situ measurements of CO2, O2, CH4, CO, N2O and SF6 mixing ratios sampled from 23, 90 and 163 m above ground on the Ochsenkopf tower in the Fichtelgebirge range, Germany (50°01´49´´ N, 11°48´30´´ E, 1022 m a.s.l.). In addition to the in-situ measurements, flask samples are taken at Ochsenkopf at approximately weekly intervals and are subsequently analysed for the same species, as well as H2, and the stable isotopes, δ13C, δ18O in CO2. The in-situ measurements of CO2 and O2 from 23 m show substantial diurnal variations that are modulated by biospheric fluxes, combustion of fossil fuels, and by diurnal changes in the planetary boundary layer height. Measurements from 163 m exhibit only very weak diurnal variability, as this height (1185 m a.s.l.) is generally above the nocturnal boundary layer. CH4, CO, N2O and SF6 show little diurnal variation even at 23 m owing to the absence of any significant diurnal change in the fluxes and the absence of any strong local sources or sinks. From the in-situ record, the seasonal cycles of the gas species have been characterized and the multi-annual trends determined. Because the record is short, the calculation of the trend is sensitive to inter-annual variations in the amplitudes of the seasonal cycles. However, for CH4 a significant change in the growth-rate was detected for 2006.5–2008.5 as compared with the global mean from 1999 to 2006 and is consistent with other recent observations of a renewed increasing global growth rate in CH4 since the beginning of 2007.

Evaluation of germ plasm for resistant to Soybean mosaic virus (SMV)

2020 ◽  
Vol 21 (1) ◽  
pp. 6-9
Author(s):  
Wuye Ria Andayanie
Keyword(s):  
Abiotic Stress ◽  
Environmental Factors ◽  
Mosaic Virus ◽  
Polyclonal Antibody ◽  
Symptom Severity ◽  
Germ Plasm ◽  
Polyclonal Antibodies ◽  
Soybean Mosaic Virus ◽  
High Yield ◽  
High Yields

Soybean superior varieties with high yields and are resistant to abiotic stress have been largely released, although some varieties grown in the field are not resistant to SMV. In addition, the opportunity to obtain lines of hope as prospective varieties with high yield and resistance to SMV is very small. The method for evaluating soybean germplasm is based on serological observations of 98 accessions of leaf samples from SMV inoculation with T isolate. The evaluation results of 98 accessions based on visual observations showed 31 genotypes reacting very resistant or healthy to mild resistant category to SMV T isolate  with a percentage of symptom severity of 0 −30 %. Among 31 genotypes there are 2 genotypes (PI 200485; M8Grb 44; Mlg 3288) with the category of visually very resistant and resistant, respectively and  Mlg 3288  with the category of mild resistant.  They have a good agronomic appearance with a weight of 100 seeds (˃10 g) and react negatively with polyclonal antibodies to SMV, except Mlg 3288 reaction is not consistent, despite the weight of 100 seeds (˃ 10 g). Leaf samples from 98 accessions revealed various symptoms of SMV infection in the field. This diversity of symptoms is caused by susceptibility to accession, when infection occurs, and environmental factors. Keywords—: soybean; genotipe; Soybean mosaic virus (SMV); disease severity; polyclonal  antibody

Atmospheric CO2 Record from In Situ Measurements at Amsterdam Island

1996 ◽  
Author(s):  
A. Guadry, ◽  
V. Kazan, ◽  
P. Monfray,
Keyword(s):  
In Situ Measurements ◽  
Atmospheric Co2

The Carbon:²³⁴Thorium ratios of sinking particles in the California Current Ecosystem 2: Examination of a thorium sorption, desorption, and particle transport model

2019 ◽  
Author(s):  
Michael Stukel ◽  
Thomas Kelly
Keyword(s):  
Organic Carbon ◽  
Water Column ◽  
Particulate Organic Carbon ◽  
Transport Model ◽  
California Current ◽  
In Situ Measurements ◽  
Power Law Distribution ◽  
Sinking Particles ◽  
Organic Carbon Concentration

Thorium-234 (234Th) is a powerful tracer of particle dynamics and the biological pump in the surface ocean; however, variability in carbon:thorium ratios of sinking particles adds substantial uncertainty to estimates of organic carbon export. We coupled a mechanistic thorium sorption and desorption model to a one-dimensional particle sinking model that uses realistic particle settling velocity spectra. The model generates estimates of 238U-234Th disequilibrium, particulate organic carbon concentration, and the C:234Th ratio of sinking particles, which are then compared to in situ measurements from quasi-Lagrangian studies conducted on six cruises in the California Current Ecosystem. Broad patterns observed in in situ measurements, including decreasing C:234Th ratios with depth and a strong correlation between sinking C:234Th and the ratio of vertically-integrated particulate organic carbon (POC) to vertically-integrated total water column 234Th, were accurately recovered by models assuming either a power law distribution of sinking speeds or a double log normal distribution of sinking speeds. Simulations suggested that the observed decrease in C:234Th with depth may be driven by preferential remineralization of carbon by particle-attached microbes. However, an alternate model structure featuring complete consumption and/or disaggregation of particles by mesozooplankton (e.g. no preferential remineralization of carbon) was also able to simulate decreasing C:234Th with depth (although the decrease was weaker), driven by 234Th adsorption onto slowly sinking particles. Model results also suggest that during bloom decays C:234Th ratios of sinking particles should be higher than expected (based on contemporaneous water column POC), because high settling velocities minimize carbon remineralization during sinking.

In-situ measurements of seismic velocity at 22 locations in the Los Angeles, California region

1982 ◽  
Author(s):  
Thomas E. Fumal ◽  
James F. Gibbs ◽  
Edward F. Roth
Keyword(s):  
Los Angeles ◽  
Seismic Velocity ◽  
In Situ Measurements

Evaluation of reanalysis and satellite-based sea surface winds using in situ measurements from Chinese Antarctic Expeditions

2013 ◽  
Vol 24 (3) ◽  
pp. 147
Author(s):  
Ming LI ◽  
Qinghua YANG ◽  
Jiechen ZHAO ◽  
Lin ZHANG ◽  
Chunhua LI ◽  
...  
Keyword(s):  
In Situ Measurements ◽  
Sea Surface ◽  
Surface Winds ◽  
Sea Surface Winds
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