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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Measurements of soil permeability anisotropy by three techniques

Roy, Pierre January 1992 (has links)
Measurements of vertical and horizontal components of hydraulic conductivity were made by the falling head permeameter, the standard piezometer and the piezometer with packing device on 4 farms in the Saint-Lawrence lowlands of Quebec, Canada. All fields are considered to be between imperfectly and slowly drained. / The values obtain by the 2 types of piezometer were calculated with the aid of 3 different equations and were compared. / The falling head permeameter technique was found to be not appropriate to study anisotropy in clay and clay loam soils due to its high variability and small volume of soil sampled. / Both piezometers were found well suited to make directional hydraulic conductivity measurements. Values of vertical hydraulic conductivity twice greater than values of horizontal hydraulic conductivity were obtained by piezometer measurements in a subsoil of a St-Benoit soil series.
2

Measurements of soil permeability anisotropy by three techniques

Roy, Pierre January 1992 (has links)
No description available.
3

Evolution of a newly reclaimed organic soil in southwestern Quebec

Millette, Jacques Armand, 1948- January 1984 (has links)
Three drainage experiments were conducted on a newly developed organic soil where three cultural methods were superimposed. Measurements of carrot yields, subsidence, water table fluctuations, subsurface drain performance, hydraulic conductivity and soil bulk density were made. Rotovating the soil produced higher carrot yields than plowing or disking during the first year. The seven-year subsidence totalled 515 mm and depended mostly on organic soil depth. Hydraulic conductivity values did not change after five years of drainage. Bulk density of the top 0.20 m increased by 71% in 6 years, whereas the values down the profile increased between 3.3 and 16.2%. / The effect of two water table depths (WTD), 0.6 and 0.9 m, in an organic soil on soil water tension, subsidence swelling and carrot yields was studied in undisturbed cores in the greenhouse. Carrot yields were reduced by the 0.9 m WTD. Subsidence with the 0.9 m WTD was more than double that of the 0.6 m WTD. Raising the water table near the surface caused the soil to swell. / Hydraulic conductivity, bulk density, fiber content and drainable porosity were measured in undisturbed organic soil profiles. Values from all four properties decreased with increasing depth.
4

Evolution of a newly reclaimed organic soil in southwestern Quebec

Millette, Jacques Armand, 1948- January 1984 (has links)
No description available.
5

Observations of water table heights and subsurface drain flows

Bostock, J. Gregory. January 1984 (has links)
No description available.
6

Observations of water table heights and subsurface drain flows

Bostock, J. Gregory. January 1984 (has links)
No description available.

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