The purpose of this study is to estimate the effect of Ontario’s Nutrient Management Act (NMA) on farm level profitability of dairy sector. NMA came into force in 2003 and sets standards for the storage and handling of nutrients for regulating farms that fit certain criteria to reduce the risk of nutrients entering surface water or groundwater, especially for farms with herd size that can produce Nutrient Units above a certain level (i.e. 300 Nutrient Units). While the Act may affect its regulated farms by incorporating additional compliance costs, it may not have the same effect on unregulated farms. Increase in the weighted-average production costs of all farms may lead to elevated milk price within a national cost of production (COP) pricing formula for dairy industry. A theoretical framework that describes the pathway by which farms’ economic performance can be affected by NMA is developed in this study. To empirically test whether NMA has effect on farm level profitability, a RE model is estimated by using the unbalanced panel data from Ontario Dairy Farm Accounting Project (ODFAP) from year 2000 to 2010. The empirical results of this study indicate that NMA may not have statistically significant effect on the profitability of regulated farms with no less than 300 Nutrient Units (NUs). A discussion is further developed to take into consideration factors that may affect this empirical results. / OMAFRA funding code: 200222

Three experiments were conducted to determine the nutritive value of black Brassica napus (BBN), yellow Brassica juncea (YBJ) and yellow Brassica napus (YBN) in pig diets. In experiment 1, effect of multi-carbohydrase supplementation on SID of AA in BBN, YBJ and YBN was evaluated in growing pigs. The YBJ had similar SID of AA to BBN and enzyme did not affect SID of most of AA. The second and third experiments investigated the effect of high dietary inclusion of BBN and YBJ on weaned pig performance and nutrient digestibility with enzyme supplementation. The studies showed that weaned pigs can be fed diets containing up to 250 g/kg of either BBN or YBJ. Enzyme supplementation improved the nutrient digestibility. In conclusion, BBN and YBJ had similar digestible nutrient contents and there were no detrimental effects detected when pigs were fed up to 250 g/kg of BBN and YBJ in weaned pigs.

Pulses are nutrient dense foods that possess many beneficial effects. The purpose of this project was to examine the prevalence and effect of pulse consumption on nutrient intake in Canadian adults (≥ 19 y). Analysis was performed on data (N = 20,156) from the 2004 Canadian Community Health Survey (Cycle 2.2). Respondents were divided into groups based on pulse consumption and levels of intake and the association between nutrient intakes and pulse consumption was examined. Analysis revealed that thirteen percent of Canadians consumed pulses on any given day, and individuals with higher pulse intakes had higher intakes of macronutrients as well as enhanced micronutrient intake. Although pulses are generally low in sodium, its intake also was higher in pulse consumers. These data indicate that pulse consumption supports dietary advice that pulses be included in healthful diets. Further studies will be necessary so that dietary advice to increase consumption of pulses will maximize their nutritional benefits.

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No description available.

No description available.

Pulses are nutrient dense foods that possess many beneficial effects. The purpose of this project was to examine the prevalence and effect of pulse consumption on nutrient intake in Canadian adults (≥ 19 y). Analysis was performed on data (N = 20,156) from the 2004 Canadian Community Health Survey (Cycle 2.2). Respondents were divided into groups based on pulse consumption and levels of intake and the association between nutrient intakes and pulse consumption was examined. Analysis revealed that thirteen percent of Canadians consumed pulses on any given day, and individuals with higher pulse intakes had higher intakes of macronutrients as well as enhanced micronutrient intake. Although pulses are generally low in sodium, its intake also was higher in pulse consumers. These data indicate that pulse consumption supports dietary advice that pulses be included in healthful diets. Further studies will be necessary so that dietary advice to increase consumption of pulses will maximize their nutritional benefits.

With climate change, forest soils of British Columbia (B.C.) will likely undergo significant increases in temperature. Changes in temperature may differentially alter steps of N cycling, altering the amount of N in various pools of the cycle. Furthermore, plant species may show a preference for certain N forms available in soils, such as ammonium, nitrate or organic N. Changes in soil N forms and plant N preferences can shift competitive interactions among conifer species in B.C. forests. Using a greenhouse incubation of forest soils from two elevations, I aimed to determine how temperature affects N cycling in soils that differ in temperature adaptations. With a conifer growth experiment where ammonium, nitrate and a mix of amino acids were applied to trees, I studied N form preferences and uptake rates of three conifer species from contrasting environments (Pseudotsuga menziesii, Picea sitchensis, and Picea engelmannii), and how N uptake in these species reacted to increases in soil temperature. Results show that the abundance of all N forms increased with temperature, but the response to warming was stronger in soils from a low elevation. Furthermore, ammonium and soluble organic N in soils increased faster with warming than nitrate. Nitrification potential was higher in the low elevation soil. This indicates that rates of soil processes, producing plant available N may increase with warming and the balance of different N forms may change. Differences in the abundance, composition, or activity of soil biota at these two locations likely caused dissimilar reactions to warming in two chemically and physically similar soils. Conifers exhibited preferences towards N forms, and these preferences are likely due to adaptation to the N form most available in native soils. On average, Douglas-fir showed preference for nitrate (a N form commonly found in warmer areas), Sitka spruce preferred ammonium (a N form high in cooler areas), and Engelmann spruce showed equal preference for organic N and ammonium (organic N is usually abundant in very cold areas). Preference as indicated by plant growth changed when species were grown at different temperatures, showing ability for acclimation in these conifers. Understanding that a soil’s history greatly affects its response to perturbation is important if we are to make predictions on how N cycling in soils may change with changing climate. Knowing how conifers utilize available soil nutrients at different temperatures will help to predict species’ future performance, composition and abundance in B.C. forests as soils warm and tree lines move north or to higher elevations. / Graduate / 0481 / 0817 / boczulst@uvic.ca

Patterns and rates of nutrient input to the forest floor in litterfall, throughfall and stemflow were investigated in plots of low and high abundance of ectomycorrhizal species. The aim of the study was to examine the comparative advantage of the ectomycorrhizal species in nutrient acquisition and cycling on nutrient-poor soils in Korup. Litterfall was similar in both forests with annual estimates of 9.00 and 8.33 t ha-1 yr-1 for LEM and HEM forests respectively. Litterfall distribution followed a mono-modal pattern, with peaks in the dry season in both forests and the HEM forest showing stronger seasonality. The concentrations N, K and Ca in total litterfall were higher in the LEM forest while those of P and Mg were higher in the HEM forest. The bulk of nutrients in total litterfall was in leaf litter with the reproductive fractions having the highest concentrations of nutrients. Ectomycorrhizal species showed lesser internal redistribution of nutrients than non-ectomycorrhizal species which resulted in their higher leaf litter concentrations of nutrients. Breakdown of litter was relatively faster in the LEM forest with an annual decomposition constant (KL) of 3.21 compared to 2.43 for the HEM forest. The reproductive fractions had relatively higher annual decomposition constants of 8.20 and 4.27 in the LEM and HEM forests respectively compared to the other fractions. The overall element mobility in decomposing leaf litter was similar in both forests and in the following order: Mg>K>Ca>P>N. Mineralization of N, P and K in the decomposing leaf litter was similar in both forests and higher in the HEM forest for Mg and Ca. Throughfall was 96.6% and 92.4%, and stemflow 1.5% and 2.2%, of gross rainfall in LEM and HEM forests respectively. Considerable amounts of Ca, Mg and P were brought to the forest canopy in gross rainfall (24-45% of total input through this route) with higher amounts of K and Ca leached from plant parts by the rainwater. The amounts of P, K and Ca in stemflow and throughfall were of the same magnitude in both forests with the enhancement of N slightly higher in the LEM forest and Mg in the HEM forest.

No description available.