Influence of different field sites on pesticide movement into subsurface drains

1995 ◽  
Vol 43 (2) ◽  
pp. 121-129 ◽  
Author(s):  
Ute Traub-Eberhard ◽  
Klaus-Peter Henschel ◽  
Werner Kördel ◽  
Werner Klein
Keyword(s):  
Subsurface Drains

A Design Method For Landslide Surface Water Drainage Control

2017 ◽  
Vol 23 (4) ◽  
pp. 275-289
Author(s):  
Benjamin D. Haugen
Keyword(s):  
Surface Water ◽  
Ad Hoc ◽  
Design Method ◽  
Design Procedure ◽  
Water Drainage ◽  
Technical Literature ◽  
Design Procedures ◽  
Landslide Mitigation ◽  
Preferential Pathways ◽  
Subsurface Drains

Abstract Infiltration of surface water increases pore water pressures in slopes and reduces their stability. Common landslide features such as tension cracks and sag ponds can act as preferential pathways for surface drainage and may increase infiltration and exacerbate pore pressure–induced instability. Surface water drainage control is likewise recommended by numerous authors as an effective and inexpensive landslide mitigation method and has been shown to reduce the risk of landslides. While robust design procedures for other geotechnical applications exist (e.g., slope reduction, subsurface drains), similar procedures for landslide surface water drainage control have remained largely ad hoc and vary among practitioners. The objective of this article is to summarize technical literature related to surface water drainage control and provide a coherent design procedure for landslides.

scholarly journals Edge-of-Field Technologies for Phosphorus Retention from Agricultural Drainage Discharge

2020 ◽  
Vol 10 (2) ◽  
pp. 634 ◽  
Author(s):  
Lipe Renato Dantas Mendes
Keyword(s):  
Surface Waters ◽  
Organic Phosphorus ◽  
Freshwater Ecosystems ◽  
Phosphorus Retention ◽  
Buffer Strips ◽  
Large Variability ◽  
Agricultural Catchments ◽  
Limiting Nutrient ◽  
Phosphorus Form ◽  
Subsurface Drains

Agriculture is often responsible for the eutrophication of surface waters due to the loss of phosphorus—a normally limiting nutrient in freshwater ecosystems. Tile-drained agricultural catchments tend to increase this problem by accelerating the transport of phosphorus through subsurface drains both in dissolved (reactive and organic phosphorus) and particulate (particle-bound phosphorus) forms. The reduction of excess phosphorus loads from agricultural catchments prior to reaching downstream surface waters is therefore necessary. Edge-of-field technologies have been investigated, developed and implemented in areas with excess phosphorus losses to receive and treat the drainage discharge, when measures at the farm-scale are not able to sufficiently reduce the loads. The implementation of these technologies shall base on the phosphorus dynamics of specific catchments (e.g., phosphorus load and dominant phosphorus form) in order to ensure that local retention goals are met. Widely accepted technologies include constructed wetlands, restored wetlands, vegetated buffer strips and filter materials. These have demonstrated a large variability in the retention of phosphorus, and results from the literature can help targeting specific catchment conditions with suitable technologies. This review provides a comprehensive analysis of the currently used edge-of-field technologies for phosphorus retention in tile-drained catchments, with great focus on performance, application and limitations.

COMPARISON OF METHODS FOR DETERMINING SATURATED HYDRAULIC CONDUCTIVITY AND DRAINABLE POROSITY OF TWO SOUTHERN ALBERTA SOILS

1986 ◽  
Vol 66 (2) ◽  
pp. 249-259 ◽  
Author(s):  
G. D. BUCKLAND ◽  
D. B. HARKER ◽  
T. G. SOMMERFELDT
Keyword(s):  
Soil Moisture ◽  
Hydraulic Conductivity ◽  
Characteristic Curve ◽  
Subsurface Drainage ◽  
Saturated Hydraulic Conductivity ◽  
Drainage Design ◽  
Moisture Characteristic ◽  
Constant Head ◽  
Subsurface Drains ◽  
Drainable Porosity

Saturated hydraulic conductivity (Ks) and drainable porosity (f) determined by different methods and for different depths were compared with those determined from the performance of drainage systems installed at two locations. These comparisons were made to determine which methods are suitable for use in subsurface drainage design. Auger hole and constant-head well permeameter Ks were 140 and 110%, respectively, of Ks determined from subsurface drains. Agreement of horizontal or vertical Ks, from in situ falling-head permeameters; to other methods was satisfactory providing sample numbers were large. Ks by Tempe cells was only 3–10% of drain Ks and in one instance was significantly lower than Ks determined by all other methods. At one site a profile-averaged value of f determined from the soil moisture characteristic curve (0–5 kPa) of semidisturbed cores agreed with that determined from drainage trials. At the other site, a satisfactory value of f was found only when the zone in which the water table fluctuated was considered. Results indicate that Ks determined by the auger hole and constant-head well permeameter methods, and f determined from the soil moisture characteristic curve of semidisturbed cores, are sufficiently reliable and practical for subsurface drainage design. Key words: Subsurface drainage, hydraulic conductivity, drainable porosity

Streamline pattern and salt leaching through progressive flooding between subsurface drains

2009 ◽  
Vol 58 (2) ◽  
pp. 199-208 ◽  
Author(s):  
Muhammad Saffar Mirjat ◽  
Derek A. Rose
Keyword(s):  
Salt Leaching ◽  
Subsurface Drains
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