scholarly journals Instruments and Methods Snow Density Profiling by Nuclear Means

1966 ◽  
Vol 6 (43) ◽  
pp. 171-176
Author(s):  
Robert D. Leighty
Keyword(s):  
Soil Moisture ◽  
Field Investigation ◽  
Present Form ◽  
Snow Density ◽  
Nuclear Technique ◽  
Density Profiles ◽  
Snow Stratigraphy ◽  
Modes Of Processing ◽  
Nuclear Detectors ◽  
Nuclear Method

Abstract During the period 8–19 May 1963 a preliminary field investigation was conducted in Greenland to determine the feasibility of using a nuclear technique to determine snow and ice density profiles. A standard nuclear soil-moisture depth probe was used with two modes of processing and recording the nuclear pulses. Example data are compared with snow densities obtained by the standard weighing technique. The nuclear method was found to be feasible; however, deficiencies related to poor resolution render the probe unusable for detailed profiling of snow stratigraphy in its present form, but expected progress in nucleonics should enable improved resolution and accuracy to be achieved by improvement of nuclear detectors.

scholarly journals Instruments and Methods Snow Density Profiling by Nuclear Means

1966 ◽  
Vol 6 (43) ◽  
pp. 171-176
Author(s):  
Robert D. Leighty
Keyword(s):  
Soil Moisture ◽  
Field Investigation ◽  
Present Form ◽  
Snow Density ◽  
Nuclear Technique ◽  
Density Profiles ◽  
Snow Stratigraphy ◽  
Modes Of Processing ◽  
Nuclear Detectors ◽  
Nuclear Method

AbstractDuring the period 8–19 May 1963 a preliminary field investigation was conducted in Greenland to determine the feasibility of using a nuclear technique to determine snow and ice density profiles. A standard nuclear soil-moisture depth probe was used with two modes of processing and recording the nuclear pulses. Example data are compared with snow densities obtained by the standard weighing technique. The nuclear method was found to be feasible; however, deficiencies related to poor resolution render the probe unusable for detailed profiling of snow stratigraphy in its present form, but expected progress in nucleonics should enable improved resolution and accuracy to be achieved by improvement of nuclear detectors.

scholarly journals Estimating snow water equivalent over long mountain transects using snowmobile-mounted ground-penetrating radar

Geophysics ◽  
2016 ◽  
Vol 81 (1) ◽  
pp. WA183-WA193 ◽  
Author(s):  
W. Steven Holbrook ◽  
Scott N. Miller ◽  
Matthew A. Provart
Keyword(s):  
Ground Penetrating Radar ◽  
Snow Water Equivalent ◽  
Ground Surface ◽  
Snow Accumulation ◽  
Accurate Estimation ◽  
Snow Density ◽  
Snow Stratigraphy ◽  
Flood Estimation ◽  
Snow Water ◽  
Ground Penetrating

The water balance in alpine watersheds is dominated by snowmelt, which provides infiltration, recharges aquifers, controls peak runoff, and is responsible for most of the annual water flow downstream. Accurate estimation of snow water equivalent (SWE) is necessary for runoff and flood estimation, but acquiring enough measurements is challenging due to the variability of snow accumulation, ablation, and redistribution at a range of scales in mountainous terrain. We have developed a method for imaging snow stratigraphy and estimating SWE over large distances from a ground-penetrating radar (GPR) system mounted on a snowmobile. We mounted commercial GPR systems (500 and 800 MHz) to the front of the snowmobile to provide maximum mobility and ensure that measurements were taken on pristine snow. Images showed detailed snow stratigraphy down to the ground surface over snow depths up to at least 8 m, enabling the elucidation of snow accumulation and redistribution processes. We estimated snow density (and thus SWE, assuming no liquid water) by measuring radar velocity of the snowpack through migration focusing analysis. Results from the Medicine Bow Mountains of southeast Wyoming showed that estimates of snow density from GPR ([Formula: see text]) were in good agreement with those from coincident snow cores ([Formula: see text]). Using this method, snow thickness, snow density, and SWE can be measured over large areas solely from rapidly acquired common-offset GPR profiles, without the need for common-midpoint acquisition or snow cores.

scholarly journals Density measurements in ice boreholes using neutron scattering

2003 ◽  
Vol 49 (167) ◽  
pp. 599-604 ◽  
Author(s):  
Elizabeth M. Morris ◽  
J. David Cooper
Keyword(s):  
Neutron Scattering ◽  
Count Rate ◽  
Fast Neutrons ◽  
Potential Contribution ◽  
Snow Density ◽  
Hydrogen Atoms ◽  
Density Profiles ◽  
Annual Variations ◽  
Neutron Probe ◽  
Calibration Equations

AbstractThis paper describes the use of a neutron probe to measure detailed stratigraphy in ice and snow. The Wallingford neutron probe, developed for measurement of soil moisture, consists of an annular radioactive source of fast neutrons around the centre of a cylindrical detector for slow (thermal) neutrons. In snow and ice, the fast neutrons lose energy by scattering from hydrogen atoms, and the number of slow neutrons arriving at the detector (the count rate) is related to the density of the medium. Calibration equations for count rate as a function of snow density and borehole diameter have been derived. Snow-density profiles from boreholes obtained using the probe show that, despite the smoothing produced by the neutron-scattering process, annual variations in density can be resolved. The potential contribution of the neutron probe to improvements in mass-balance monitoring is discussed.

scholarly journals Earthworm Abundance and Soil Characteristics Following Cocoa Waste and Manure Applications

2020 ◽  
Vol 36 (1) ◽  
Author(s):  
Erwin Prastowo ◽  
Lina Dwi Agustina ◽  
Cahyo Prayogo
Keyword(s):  
Soil Moisture ◽  
Soil Fertility ◽  
Soil Characteristics ◽  
Field Investigation ◽  
Organic Wastes ◽  
Fertility Level ◽  
Total N ◽  
Organic C ◽  
Top Soil ◽  
Earthworm Population

Soil fertility level improvement in an environmentally friendlier way has been a key to provide a sustainable cocoa production. Earthworms, as decomposeragents in soil, may provide a sustainable way of improving soil fertility level. The objective of this study was to quantify top soil earthworm population andsome important soil characteristics, e.g. soil moisture, organic C, total N, and pH to see if there was any response observed due to different level and type oforganic waste applications. Their surface populations, i.e. at 5–10 cm depth, within cocoa circle were investigated with respect to different type of organic wasteapplications, i.e. cocoa pod waste, cocoa leaf waste, and sheep manure. For cocoa derived organic matter, the level of application was arranged at 5, 10, and 20 ton/ha to obtain an optimal condition at which the highest population of earthworm is obtained. A field investigation was performed at a square of 900 cm2 sizedarea, and extending down to 5–10 cm depth. Additionally, the effect of organic waste to top soil characteristics were also determined mainly to some importantparameters such as soil moisture, organic carbon, total nitrogen, and soil pH (H2O). Our analysis suggest that field heterogeneity condition may limit the conclusion, mainly related to the question of to what extent the effect of organic wastes to the changes in terms of soil characteristics. The application of organic wastes was able to increase the population of earthworms. Their highest abundance was obtained following the application of cocoa pod at 20 ton/ha, which was about 5 times higher than the population in the control. 

scholarly journals Hydrological functioning of forested catchments, Central Himalayan Region, India

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Nuzhat Qazi
Keyword(s):  
Soil Moisture ◽  
Water Discharge ◽  
Field Investigation ◽  
Himalayan Region ◽  
Annual Rainfall ◽  
Hydrological Response ◽  
Dry Period ◽  
Catchment Scale ◽  
Forested Catchments ◽  
Hydrological Functioning

Abstract Background Central Himalayan forested catchments provide fresh water supply and innumerable ecosystem services to millions of people. Hence, the understanding of linkages between forests and water is very crucial for availability and quality of water at catchment scale. Therefore, the present study aims to understand the hydrological response of two forested catchments (namely, Arnigad and Bansigad) in the Central Himalayan Region. Methods Three-years’ data (March, 2008 to February, 2011) were collected from meteorological and hydrological stations in Arnigad and Bansigad catchments. The present paper describes the mean hydrological response of these forested catchments investigated through detailed field investigation. Results The annual hyetograph analysis revealed that the rainfall at both the catchments was highly seasonal, and wet-period (June–September) plays a key role in catchment functioning. Exceedance of rainfall threshold of ~ 200 mm (~ 10% of annual rainfall) significantly increased streamflow generation in both catchments. In Arnigad, the stream was perennial with a mean baseflow of ~ 83 mm per month (~ 6% of annual baseflow) whereas, Bansigad had greater seasonality due to lack of streamflow during the pre-wet-period (March–May). Separation of hydrographs in Arnigad and Bansigad catchments i.e. stormflow (6% and 31%, respectively) and baseflow (50% and 32%, respectively) helped to understand the probability of flooding during wet-period and drought during dry-period. The forest ecosystem in Arnigad displayed healthier hydrological functioning in terms of reduced stormflow (82%), and enhanced baseflow (52%), soil moisture (13%), steady infiltration rate (22%) and lag time (~ 15 min) relative to Bansigad. These enhanced values indicated soil capability to store water in the forested catchment (Arnigad) and helped to understand the volume of water (discharge) that was available during dry-period. The lower denudation rate at Arnigad by 41% resulted in decreased suspended sediment (18%) and bed load (75%) compared to Bansigad. Further, the enhanced dissolved solids in the Arnigad stream resulted from the higher organic matter generated in the forest floor. Conclusion This study shows that rainfall during the wet-period was the main driver of hydrological functioning, whereas, forests provided substantial services by regulating water balance, soil moisture and sediment budget through different mechanisms of forest components at catchment-scale in the Central Himalayan Region.

scholarly journals Hydrological Functioning of Forested Catchments, Central Himalayan Region, India.

2020 ◽  
Author(s):  
Nuzhat Ul Qayoom Qazi
Keyword(s):  
Soil Moisture ◽  
Water Discharge ◽  
Field Investigation ◽  
Himalayan Region ◽  
Annual Rainfall ◽  
Hydrological Response ◽  
Dry Period ◽  
Catchment Scale ◽  
Forested Catchments ◽  
Hydrological Functioning

Abstract Background: Central Himalayan forested catchments provide fresh water supply and innumerable ecosystem services to millions of people. Hence, the understanding of linkages between forests and water is very crucial to recognize for availability and quality of water at catchment scale. Therefore, present study aims to understand hydrological response of two forested catchments (namely, Arnigad and Bansigad) in the Central Himalayan Region.Methods: Three-year data (March, 2008 to February, 2011) were collected from meteorological and hydrological stations installed at Arnigad and Bansigad catchments. The present paper displays mean hydrological response of forested catchments through detailed field investigation.Results : The annual hyetograph analysis revealed that the rainfall at both the catchments was highly seasonal, and wet-period (June-September) plays a key role in catchment functioning. Exceedance of rainfall threshold of ~200 mm (~10% of annual rainfall) significantly increased streamflow generation at both the catchments. At Arnigad, stream was perennial with a mean baseflow of ~83 mm per month (~ 6 % of annual baseflow) whereas, Bansigad had greater seasonality due to lack of streamflow during the pre-wet-period (March-May). Separation of hydrographs at Arnigad and Bansigad catchments i.e. stormflow (6% and 31%, respectively) and baseflow (50% and 32%, respectively) helped to understand the probability of flooding during wet-period and drought during dry-period. Forest ecosystem at Arnigad improved the hydrological functioning by: reducing stormflow (82%), and enhancing: baseflow (52%), soil moisture (13%), steady infiltration rate (22%) and lag time (~15 minutes) relative to Bansigad. These enhanced values indicated soil capability to store water at forested catchment (Arnigad) and helped to understand the volume of water (discharge) that was available during dry-period. The decrease of denudation rate (at Arnigad) by 41% resulted decrease in suspended sediment (18%) and bed load (75%) compared to Bansigad. Further, the enhancement of dissolved solids in stream resulted due to maximum organic matter generated in forest floor of Arnigad. Conclusion: This study accomplishes that rainfall during the wet-period was the main driver of hydrological functioning, whereas, forests provided substantial services by regulating water balance, soil moisture and sediment budget at Arnigad catchments through different mechanisms of forest components at catchment-scale in the Central Himalayan region.

Experimental analysis of snow micropenetrometer (SMP) cone penetration in homogeneous snow layers

2013 ◽  
Vol 50 (10) ◽  
pp. 1044-1054 ◽  
Author(s):  
Alec van Herwijnen
Keyword(s):  
Penetration Depth ◽  
Experimental Studies ◽  
Small Diameter ◽  
High Porosity ◽  
Snow Density ◽  
Cone Penetration ◽  
Avalanche Forecasting ◽  
Snow Stratigraphy ◽  
Image Velocimetry ◽  
Compaction Zone

The cone penetration test (CPT) is widely used to determine in situ soil and snow characteristics and stratigraphy. For avalanche forecasting, knowledge about snow stratigraphy is of crucial importance. Portable electric cone penetrometers have therefore been developed with the goal of obtaining rapid and accurate measurements of snow stratigraphy. The most widely used electric penetrometer is the snow micropenetrometer (SMP), a constant-speed small-diameter cone penetrometer. The SMP was specifically designed to study snow and is not a penetrometer in the geotechnical sense, as the diameter of the SMP cone (5 mm) is comparable to the typical size of snow grains (0.1 to 1 mm). Previous numerical and experimental studies of the CPT in granular materials have highlighted the importance of material compaction around the cone. Nevertheless, given the high porosity of snow, compaction of failed elements around the SMP cone is generally neglected when interpreting SMP force signals. To verify this assumption, microcomputed tomography and particle image velocimetry were used to investigate the deformation of snow during SMP cone penetration. Results from laboratory experiments with uniform snow show that a compaction zone around the SMP tip develops during penetration. The size of the compaction zone was on average twice as large as the actual size of the cone, increasing with increasing snow density. Furthermore, an average penetration depth of about 40 mm was required for the compaction zone to develop fully. This critical penetration depth roughly decreased with increasing snow density. These results show that the compaction zone around the SMP tip is far from negligible and has to be accounted for when interpreting SMP force measurements.

scholarly journals Effect of land configuration ways on soil moisture and sesame seed yield in Ethiopia

2021 ◽  
pp. 1-6
Author(s):  
Goitom Teame
Keyword(s):  
Soil Moisture ◽  
Seed Yield ◽  
Agricultural Research ◽  
Block Design ◽  
Sesame Seed ◽  
Moisture Stress ◽  
Field Investigation ◽  
Management Options ◽  
Dry Spell ◽  
Growth Habits

Sesame is an erect herbaceous annual plant with both single-stemmed and branched growth habits. Sesame seed yield is easily affected by soil moisture stress in semi-arid climate. Good vertisol management options that conserve moisture during dry spell period and drain excess moisture during wet periods is vital. Study area has limited rainfall therefore evidences on effect of land configuration ways on soil moisture and sesame yield is critical. A field investigation was conducted at Humera Agricultural Research Center (HuARC) during 2016 growing season in vertisol soil type. The experiment was laid out by randomized complete block design (RCBD) with three replication that consists of three land configuration ways or methods namely flat, ridge and furrow, and bed furrow. Sesame variety, Setit-1, was sown with 40 cm and 10 cm spacing between rows and plants respectively. The analysis revealed that land configuration methods had a significant effect on soil moisture and agronomic parameter. The highest sesame seed yield (558 kg ha-1) was recorded at ridge and furrow, while the lowest (400 kg ha-1) was found at the flat land configuration method. The ridge and furrow methods conserved best soil moisture for highest plant and seed yield performance.

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