Measurement of slope runoff in a permafrost region

1983 ◽  
Vol 20 (2) ◽  
pp. 361-365 ◽  
Author(s):  
Peter Steer ◽  
Ming-ko Woo
Keyword(s):  
Surface Runoff ◽  
Subsurface Flow ◽  
High Arctic ◽  
Surface Flow ◽  
Ice Formation ◽  
Permafrost Region ◽  
Experimental Site ◽  
Permafrost Table ◽  
Discharge Measurements ◽  
Slope Runoff

Installations at a High Arctic experimental site that is underlain by continuous permafrost allowed the measurement of slope runoff. Surface flow was collected near the base of the slope and the water was led to a flume with a V-notch weir. The water level in the flume was recorded and subsequently converted to discharge measurements. Subsurface flow was intercepted by an impermeable flow barrier set in a trench dug down to the permafrost table and later back-filled by the excavated slope materials. Water draining from above the flow barrier was fed into another flume unit similar to that for surface runoff. During the operational period, regular inspection of the flumes was required to ensure the prevention of ice formation or evaporative losses from the water in the flumes. Keywords: surface flow, subsurface flow, slope hydrology, permafrost.

Slope hydrology as influenced by thawing of the active layer, Resolute, N.W.T.

1983 ◽  
Vol 20 (6) ◽  
pp. 978-986 ◽  
Author(s):  
Ming-ko Woo ◽  
Peter Steer
Keyword(s):  
Surface Topography ◽  
Active Layer ◽  
Surface Runoff ◽  
Storage Capacity ◽  
Water Storage ◽  
High Arctic ◽  
Surface Flow ◽  
Water Storage Capacity ◽  
Continuous Permafrost ◽  
Generate Surface

High arctic slopes have a shallow active layer that thaws unevenly during summer. The result is often a lack of agreement between the configuration of the frost table and the surface topography, and this has effects on the slope hydrology. (1) Areas with a shallow frost table favour surface runoff but areas with a deeper frost table require a thick zone of saturation to generate surface flow. Uneven thaw depths then cause alternating seepage and re-emergence of water down a slope. (2) The configuration of the frost table is highly dynamic, causing day to day changes in water storage capacity in the active layer. (3) A frost table with local depressions can pond up groundwater, which may be rapidly released when part of the frozen sill is breached by continual thawing. (4) The topographical drainage divide may not correspond with the subsurface drainage divide as defined by the frost table, thus allowing groundwater to drain laterally across topographical boundaries. These findings show that a knowledge of the frost table behaviour, both spatially and temporally, is essential to the study of slope hydrology in continuous permafrost terrains.

Loss of phosphorus and nitrogen in runoff and subsurface drainage from high and low input pastures grazed by sheep in southern Australia

Soil Research ◽  
2008 ◽  
Vol 46 (2) ◽  
pp. 161 ◽  
Author(s):  
A. R. Melland ◽  
M. R. Mc Caskill ◽  
R. E. White ◽  
D. F. Chapman
Keyword(s):  
Surface Runoff ◽  
Water Flux ◽  
Subsurface Flow ◽  
Surface Flow ◽  
Nutrient Loss ◽  
Subsurface Water ◽  
Balance Model ◽  
Nutrient Inputs ◽  
N Losses ◽  
Primary Determinant

High rates of fertiliser applied to boost pasture growth in the southern Australian sheep industry may lead to eutrophication of waterways and groundwater degradation. A field study was used to investigate whether higher fertiliser and stocking rates would increase nutrient loss in runoff and subsurface flow from pastures. Phosphorus (P) and nitrogen (N) concentrations in surface and subsurface flow were measured from 1998–2000 in four 0.5-ha hillslope plots. Surface flow volume was measured directly and subsurface water flux was estimated using soil moisture data and a water balance model. A simulated rainfall study was also conducted using 0.64-m2 plots. The treatments represented were: a low-P set-stocked sown pasture (SS low P), a high-P set-stocked sown pasture (SS high P), a high-P sown pasture in a 4-paddock rotation (RG 4-pdk), and an unsown set-stocked pasture (Low P volunteer). No runoff from the hillslope occurred in 1999, while the volume of runoff in 1998 and 2000 varied from 0.1 to 68 mm/year across the 4 hillslope plots. More P was lost via surface runoff (up to 0.25 kg P/ha.year) than subsurface flow (up to 0.027 kg P/ha.year). However, N loads were greater in subsurface flows (3.2–10.6 kg N/ha.year) than surface runoff (0.04–2.74 kg N/ha.year). Phosphorus concentrations were higher in runoff from the high P treatments (0.34–0.83 mg P/L) than the set-stocked low P treatment (0.19–0.22 mg P/L). Higher TP concentrations in runoff from the high P treatments were associated with greater labile P contents in the soil, dung, and herbage. However, the volume of runoff, rather than the pasture treatment, was the primary determinant of nutrient loss. Avoiding high nutrient inputs in seasonally waterlogged areas, sowing perennial pastures, and minimising stock camping helps minimise P losses to waterways and N losses to groundwater.

Optimization of Artificial Wetland Design for Removal of Indicator Microorganisms and Pathogenic Protozoa

1999 ◽  
Vol 40 (4-5) ◽  
pp. 363-368 ◽  
Author(s):  
C. P. Gerba ◽  
J. A. Thurston ◽  
J. A. Falabi ◽  
P. M. Watt ◽  
M. M. Karpiscak
Keyword(s):  
Subsurface Flow ◽  
Individual Performance ◽  
Surface Flow ◽  
Enteric Pathogens ◽  
Fecal Coliforms ◽  
Treatment Level ◽  
Artificial Wetland ◽  
Indicator Microorganisms ◽  
Duckweed Pond ◽  
Wetland Design

The enhancement of water quality by artificial wetland systems is increasingly being employed throughout the world. Three wetlands were studied in Tucson, AZ to evaluate their individual performance in the removal of indicator bacteria (coliforms), coliphage, and enteric pathogens (Giardia and Cryptosporidium). A duckweed-covered pond, a multi-species subsurface flow (SSF) and a multi-species surface flow (SF) wetland were studied. Removal of the larger microorganisms, Giardia and Cryptosporidium, was the greatest in the duckweed pond at 98 and 89 percent, respectively. The lowest removal occurred in the SF wetland, 73 percent for Giardia and 58 percent removal for Cryptosporidium. In contrast, the greatest removal of coliphage, total and fecal coliforms occurred in the SSF wetland, 95, 99, and 98 percent respectively, whereas the pond had the lowest removals (40, 62, and 61 percent, respectively). Sedimentation may be the primary removal mechanism within the duckweed pond since the removal was related to size, removal of the largest organisms being the greatest. However, the smaller microorganisms were removed more efficiently in the SSF wetland, which may be related to the large surface area available for adsorption and filtration. This study suggests that in order to achieve the highest treatment level of secondary unchlorinated wastewater, a combination of aquatic ponds and subsurface flow wetlands may be necessary.

scholarly journals Post-treatment of tannery wastewater using pilot scale horizontal subsurface flow constructed wetlands (polishing)

2017 ◽  
Vol 77 (4) ◽  
pp. 988-998 ◽  
Author(s):  
Tadesse Alemu ◽  
Andualem Mekonnen ◽  
Seyoum Leta
Keyword(s):  
Removal Efficiency ◽  
Batch Reactor ◽  
Subsurface Flow ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Surface Flow ◽  
Tannery Wastewater ◽  
Treated Effluent ◽  
Horizontal Subsurface Flow ◽  
Pollutants Removal

Abstract In the present study, a pilot scale horizontal subsurface flow constructed wetland (CW) system planted with Phragmites karka; longitudinal profile was studied. The wetland was fed with tannery wastewater, pretreated in a two-stage anaerobic digester followed by a sequence batch reactor. Samples from each CW were taken and analyzed using standard methods. The removal efficiency of the CW system in terms of biological oxygen demand (BOD), chemical oxygen demand (COD), Cr and total coliforms were 91.3%, 90%, 97.3% and 99%, respectively. The removal efficiency for TN, NO3− and NH4+-N were 77.7%, 66.3% and 67.7%, respectively. Similarly, the removal efficiency of SO42−, S2− and total suspended solids (TSS) were 71.8%, 88.7% and 81.2%, respectively. The concentration of COD, BOD, TN, NO3−N, NH4+-N, SO42 and S2− in the final treated effluent were 113.2 ± 52, 56 ± 18, 49.3 ± 13, 22.75 ± 20, 17.1 ± 6.75, 88 ± 120 and 0.4 ± 0.44 mg/L, respectively. Pollutants removal was decreased in the first 12 m and increased along the CW cells. P. karka development in the first cell of CW was poor, small in size and experiencing chlorosis, but clogging was higher in this area due to high organic matter settling, causing a partial surface flow. The performance of the pilot CW as a tertiary treatment showed that the effluent meets the permissible discharge standards.

Separation of surface flow from subsurface flow in catchments using runoff coefficient

2021 ◽  
Author(s):  
A. Afshar Ardekani ◽  
T. Sabzevari ◽  
A. Torabi Haghighi ◽  
A. Petroselli
Keyword(s):  
Subsurface Flow ◽  
Surface Flow ◽  
Runoff Coefficient

scholarly journals Assessment of catchment response and calibration of a hydrological model using high-frequency discharge–nitrate concentration data

2013 ◽  
Vol 44 (6) ◽  
pp. 995-1012 ◽  
Author(s):  
Rajesh R. Shrestha ◽  
Karsten Osenbrück ◽  
Michael Rode
Keyword(s):  
Surface Runoff ◽  
High Frequency ◽  
Hydrological Model ◽  
Nitrate Concentration ◽  
Subsurface Flow ◽  
Nitrate Transport ◽  
Response Analysis ◽  
Catchment Scale ◽  
Concentration Data ◽  
High Frequency Discharge

This study uses a high-frequency discharge and nitrate concentration dataset from the Weida catchment in Germany for the catchment scale hydrologic response analysis. Nitrate transport in the catchment is mostly conservative as indicated by the nitrate stable isotope (δ15N and δ18O) analysis. Discharge–nitrate concentration data from the catchment show distinctive patterns, suggesting flushing and dilution response. A self-organizing feature map-based methodology was employed to identify such patterns or cluster in the datasets. Based on knowledge of the catchment conditions and prevailing understanding of discharge–nitrate concentration relationship, the clusters were characterized into five qualitative flow responses: (1) baseflow; (2) subsurface flow increase; (3) surface runoff increase; (4) surface runoff recession; and (5) subsurface flow decrease. Such qualitative flowpaths were used as soft data for a multi-objective calibration of a hydrological model (WaSiM-ETH). The calibration led to a reasonable simulation of overall discharge (Nash–Sutcliffe coefficient: 0.84) and qualitative flowpaths (76% agreement). A prerequisite for using such methodology is limited biogeochemical transformation of nitrate (such as denitrification).

A critical evaluation of a pilot scale subsurface flow wetland: 10 years after commissioning

1997 ◽  
Vol 35 (5) ◽  
pp. 337-343 ◽  
Author(s):  
Allan Batchelor ◽  
Pierre Loots
Keyword(s):  
Critical Evaluation ◽  
Subsurface Flow ◽  
Plug Flow ◽  
Pilot Scale ◽  
Preliminary Evidence ◽  
Surface Flow ◽  
Organic Load ◽  
Hydraulic Load ◽  
Flow Through ◽  
Back Mixing

A pilot scale subsurface flow wetland, commissioned in 1986, has been continuously operated since 1990 at a hydraulic load of 330 mm/day and a corresponding organic load of 1200 kg/ha·day. At these loading rates preliminary evidence suggests that the microbial biomass in the wetland was dominated by anaerobes. Attempts to increase the hydraulic load resulted in surface flooding which was attributed to suspended solids clogging the surface. Despite short circuiting, revealed by tracer studies, COD removal exceeded 70%. The hydraulic flow through the wetland was modelled and was described as modified plug flow with a degree of back mixing. A comparative costing exercise revealed that the unit treatment cost of a combination of a subsurface flow wetland/nitrification column, surface flow wetland was lower than that of an activated sludge system treating the same volume of effluent.

scholarly journals Granulometric characterization of sediments transported by surface runoff generated by moving storms

2008 ◽  
Vol 15 (6) ◽  
pp. 999-1011 ◽  
Author(s):  
J. L. M. P. de Lima ◽  
C. S. Souza ◽  
V. P. Singh
Keyword(s):  
Grain Size ◽  
Surface Runoff ◽  
Laboratory Experiments ◽  
Overland Flow ◽  
Temporal Distribution ◽  
Surface Flow ◽  
Constant Speed ◽  
Stream Power ◽  
Sediment Grain Size ◽  
Rain Simulator

Abstract. Due to the combined effect of wind and rain, the importance of storm movement to surface flow has long been recognized, at scales ranging from headwater scales to large basins. This study presents the results of laboratory experiments designed to investigate the influence of moving rainfall storms on the dynamics of sediment transport by surface runoff. Experiments were carried out, using a rain simulator and a soil flume. The movement of rainfall was generated by moving the rain simulator at a constant speed in the upstream and downstream directions along the flume. The main objective of the study was to characterize, in laboratory conditions, the distribution of sediment grain-size transported by rainfall-induced overland flow and its temporal evolution. Grain-size distribution of the eroded material is governed by the capacity of flow that transports sediments. Granulometric curves were constructed using conventional hand sieving and a laser diffraction particle size analyser (material below 0.250 mm) for overland flow and sediment deliveries collected at the flume outlet. Surface slope was set at 2%, 7% and 14%. Rainstorms were moved with a constant speed, upslope and downslope, along the flume or were kept static. The results of laboratory experiments show that storm movement, affecting the spatial and temporal distribution of rainfall, has a marked influence on the grain-size characteristics of sediments transported by overland flow. The downstream-moving rainfall storms have higher stream power than do other storm types.

SURFACE RUNOFF AND LATERAL SUBSURFACE FLOW AS A RESPONSE TO CONSERVATION TILLAGE AND SOIL-WATER CONDITIONS

2005 ◽  
Vol 48 (6) ◽  
pp. 2137-2144 ◽  
Author(s):  
D. D. Bosch ◽  
T. L. Potter ◽  
C. C. Truman ◽  
C. W. Bednarz ◽  
T. C. Strickland
Keyword(s):  
Soil Water ◽  
Surface Runoff ◽  
Conservation Tillage ◽  
Subsurface Flow ◽  
Water Conditions ◽  
Soil Water Conditions
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