No description available.

No description available.

Thesis (Ph. D.)--Illinois State University, 2006. / Title from title page screen, viewed on May 14, 2007. Dissertation Committee: Steven A. Juliano (chair), Roger C. Anderson, L. Philip Lounibos, Wade A. Nichols, William L. Perry. Includes bibliographical references (leaves 145-162) and abstract. Also available in print.

Same of the philosophical aspects of modelling are discussed along with the importance of understanding primary marine food-web components. Howe Sound, a coastal embayment on the British Columbia coast, is examined as a base study area, and field sampling methods as well as laboratory techniques are summarized. The main body of the investigation involves the development of a mathematical description of phytoplankton population growth and distribution as a function of biological and physical circulation parameters in the sound. This is accomplished by dividing the sound into zones and modelling primary productivity as a result of certain key environmental forcing functions. Transport between zones is shown to affect spatial timing and distribution. Observed and predicted values of nutrients, temperature, extinction coefficients, zooplankton biomass, and phytoplankton productivity and biomass are compared as the model is refined. It is then used to simulate the effects of a delayed spring on productivity in Howe Sound, as well as to model growth in Indian /Arm, an adjacent embayment. Simulated annual productivity in Have Sound is 235, 316 and 384 gC‧m⁻²‧yr⁻¹ in the down inlet direction for the three model zones. With a delayed spring the values are reduced to 200, 308 and gC‧m⁻²‧yr⁻¹ and comparisons are made with observed data in Howe Sound in 1974 when poor spring weather conditions prevailed. In Indian Arm the model predicts a spatial productivity distribution of 318, 256 and 239 gC‧m⁻²‧yr⁻¹, values which agree with field observations of two workers. The general applicability of such models to complex ecosystems is discussed. / Science, Faculty of / Zoology, Department of / Graduate

No description available.

This research examines scientific productivity among authors in natural scientific reference groups. A broad literature review surveys models of knowledge production, including measures of scientific products at different levels of abstraction. Data is drawn from authors in ten specialty areas, elites identified by co-citation analysis. These co-citation clusters are analyzed in general, in disciplinary sets, and as specialty groups. Results show that variance in the productivity of elite authors is not predictable on the basis of stratification variables. Descriptive differences in disciplines and specialties reflect contextual diversity in the social production of scientific knowledge. Differences in average annual paper publication, citation and highly cited paper publication do not correspond to differences in career age, job sector or prestige of highest degree. In general, stratification by experience and affiliation is not reflected in the variation of bibliometric measures of scientific productivity. This suggests that co-citation clusters are partially comparable to general populations of science, since author productivity is not simply predicted on the basis of social stratification for either type of population. Co-citation cluster authors are heterogeneous, like scientists in general, and their bibliometric differences do not correspond to variation in experience or affiliation. / Master of Science

Thesis (M.Sc. (Agriculture (Crop Science)) -- University of Limpopo, 2004. / Canon Collins Educational Trust of Southern Africa (CCETSA), and the National Research Foundation (NRF)

Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 127-138). Also available on the World Wide Web.

Thesis (M.S.)--Naval Postgraduate School, 1981. / Cover title. "September 1981." Includes bibliographical references (leaves 108-120).

M.Sc. (Botany) / Eight sampling points were selected on the Jukskei River so that the impact of inflows from various localities on the quality of the river water could be determined. Samples were taken every two weeks from the 4th April 1983 to 19th March 1984. The temperature, conductivity, dissolved oxygen and pH of the water were determined on site. Determinations of total phosphorus (as p-po1-), nitrate (NO), chloride (C11 and chlorophyll a were done. After filtration the water of each sample was inoculated with Euglena gracilis and incubated for four days under controlled conditions after which the Euglena chlorophyll-content, primary productivity and biological growth potential were measured...