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A one year water table management field study was conducted on a Soulanges sandy loam soil in Soulanges county, Quebec. Two controlled water table levels, i.e. 0.5 m and 0.75 m from the soil surface, as well as free outlet conventional drainage treatments were established in monocropped corn (Zea mays L.) and corn intercropped with ryegrass (Lolium multiflorum Lam) plots. / Cropping system showed no significant effects on evapotranspiration, and on soil moisture distribution. It was observed that the 0.5 m and 0.75 m controlled water tables (CWT) provided the same soil moisture trends in both cropping systems. The soil moisture was always higher in controlled water table plots compared to freely drained plots. The water use efficiency of 0.75 m CWT in both cropping systems was high compared to 0.5 m CWT. / The soil moisture contents at three depths were only 2% to 10% less in intercropped plots compared to monocropped plots. The soil moisture was 12 to 13% higher in CWT plots compared to freely drained plots for both cropping systems. The soil moisture in 0.5 m CWT and 0.75 m CWT plots was not significantly different. The average water table levels in monocropped plots were not significantly different from intercropped plots.

The above-ground part of a plant has an important contribution to plant development and yield production. Physiological activities of a plant canopy highly correlate to morphology of plant vegetation. Obviously, leaf area index is a good indicator for leaf area, but does not provide any information about the spatial architecture of plant canopy. With the development of fractal theory, a quantitative toot is now available for the investigation of complex objects and shapes such as plant structure. Vegetation structure of corn ( Zea mays L.) and soybean (Glycine max. (L.) Merr.] plants might be affected by the plant population density (low, normal, high) of each crop and corn-soybean intercropping. Skeletonized leaf-off images provided acceptable information to estimate the fractal dimension of the soybean plant 2-dimensionally, using the box-counting method. Fractal dimension varied among soybean treatments, with rankings: low > normal > intercrop > high, in the overall mean and normal ≈ intercrop ≈ low > high, in the slope of time plots. An adjustment of field corn plants to treatments, by changing the orientation of the plane of developed leaves with respect to the row, was observed. Thus, the fractal dimension of corn plant skeletal images from each of two sides, side I (parallel to row) and side 2 (perpendicular to row), was analyzed. On the basis of overall means of fractal dimension, treatments were ranked as: high > normal ≈ intercrop ≈ low for side 1 and intercrop > low ≈ normal > high for side 2. In both cases of soybean and corn plants, leaf area index, plant height and number of leaves (only in case of soybean plant) increased over the experiment for all the treatments, indicating a positive correlation with fractal dimension. In contrast, light penetration decreased during crop development, indicating a negative correlation with fractal dimension. Furthermore, a modified version of the Beer-Lambert equation, in which fractal dimension mu

Thesis (Ph. D.)--Oregon State University, 1989. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.

Thesis (Ph.D.)--University of Alberta, 2010. / Title from PDF file main screen (viewed on May 27, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Plant Science, [Department of] Agricultural, Food and Nutritional Science, University of Alberta. Includes bibliographical references.

Thesis (M.Sc.)--University of Alberta, 2010. / Title from PDF file main screen (viewed on May 28, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Rangeland and Wildlife Resources, Department of Agriculture, Food and Nutritional Science, University of Alberta. Includes bibliographical references.

Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 74-80). Also available on the Internet.

Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Includes bibliographical references (leaves 74-80). Also available on the Internet.