Research was conducted to compare the effects of composted dairy manure and raw dairy manure alone, or in combination with supplemental inorganic fertilizer, on soil chemical properties and Coastal bermudagrass [Cynodon dactylon (L.) Pers.] yield and nutritive value. Composted dairy manure was surface applied at rates of 14 (125 kg N ha-1), 29 (250 kg N ha-1) and 57 (500 kg N ha-1) Mg dry matter (DM) ha-1, and raw dairy manure was surface applied at a rate of 54 (420 kg N ha-1) Mg DM ha-1 to established bermudagrass. Selected compost and manure plots received supplemental inorganic N at rates of 56, 84 and 112 kg ha-1 cutting-1 or 112 kg ha-1 cutting-1 of supplemental N with supplemental inorganic phosphorus or potassium at rates of 112 kg P2O5 ha-1 yr-1 and 112 kg K2O ha-1 cutting-1, respectively. Composted dairy manure (29 and 57 Mg DM ha-1) or raw manure alone increased cumulative forage yields compared to the untreated check in both years of the study, but were less than those obtained using only inorganic fertilizer. Application of 56 kg N ha-1 cutting-1 or more of supplemental N to compost (29 and 57 Mg DM ha-1) or iv manure produced forage yields that were equal to or greater than those obtained using inorganic fertilizer alone. However, increasing compost rate did not increase tissue N concentrations regardless of supplemental inorganic N rate. Yield and tissue K concentrations were increased in the second growing season when supplemental inorganic K was applied to 29 Mg ha-1 of compost or 54 Mg ha-1 of raw dairy manure. No yield response was observed when supplemental inorganic P was applied to compost or manure. Soil pH and concentrations of NH4, NO3, K, Ca, Mg and Mn were increased by application of compost or manure. Soil P concentrations in the 0 to 5-cm zone exceeded 200 mg kg-1 when compost was applied at the high rate. Dairy manure compost was an effective nutrient source for bermudagrass hay production, but will require the use of supplemental N and, in some cases, K to achieve yields comparable to inorganic fertilizer.

The purpose of this study is to investigate the distribution and growth of the Black-Disease-causing Terpios hoshinota, including the effects of light, depth and nutrient on their growth at Green Island and Orchid Island. We also simulated the future coverage of black disease based on present data. Most T. hoshinota colonies were distributed at 2-3 meters (0-62 ind./100 m2) and the densities decrease with depth (0-5 ind./100 m2, at 10 m). The BD density at north and east coast were higher than that at west coast at Green Island, but no such difference occurred at Orchid Island. There were many small sponges and the number decrease with size. The frequency distribution of log-transformed lengths displayed a normal distribution. In comparing various recruitment models, i.e., normal, uniform, exponential and seasonal, we found that the actual size distribution is only compatible with the exponential temporal pattern. Thus more and more recruits may be entering the population continuously. The average growth rate of T. hoshinota is 0.18 cm/day, therefore the largest sponge at Green Island might have grown for only 2-4 years (340 cm).Two independent nutrient experiments did not detect the effects of nutrient addition on growth rates of the sponge. Comparison of BD densities and house numbers near the reef failed to reveal correlation. Most sponge colonies could not grow normally when shaded. The sponges transported to deeper water (15-20 m) might suffer tissue loss, but if they survived, they grew as fast as those controls at shallow waters (5-10 m). Growth rates of T. hoshinota differed by seasons within our testing period from April to July, 2008. The sponge expanded slower on non-coral substrate, at about 55% the rate, than those on corals. T. hoshinota grow on artificial substrate like glass, antifouling coatings, soft corals and other sponges. Using BD densities, sizes, growth rates and coral coverage, we simulated the BD colony distribution to predict its future coverage. We found that the sponge has the potential to cover the shallow reefs in 3-5 years at Green Island. The actual rate of increase at Gon-guan reef between 2007 and 2008 supports the above prediction.

Thesis (Ph. D.)--University of Queensland, 2002. / Includes bibliographical references.

Thesis (M.S.) in Oceanography--University of Maine, 2002. / Includes vita. Bibliography: leaves 72-78.

Earlier studies indicate that the interaction between heterotrophic bacteria and dissolved organic matter is rather different in rivers and estuaries. The aim of my thesis was to elucidate if bacteria are regulated differently in the Råne river and estuary during a spring situation. Surface water was collected at both locations and a bioassay performed to study limiting substances for bacterial production, proportion bio-available dissolved organic carbon (DOC) in the water and bacterial growth efficiencies (BGE). The Carbon, Nitrogen and Phosperous concentrations were all higher in the estuary than in the river. The bioassay showed that nitrogen-phosphorus limited the bacterial production at both locations, while DOC occurred in excess. The bio-available part of the DOC pool was larger in the estuary (~6%) than in the river (~3%). However, the BGE was much higher in the river (~40%) than in the estuary (~5%), indicating that a larger proportion of the consumed DOC was used for respiration in the estuary. I conclude that heterotrophic bacteria are limited by the same substance, but that the bacterial metabolism is quite differently regulated in the river and in the estuary.

Currently, the information available concerning requirements for optimum crop growth and development, dry matter production, and nutrient uptake and partitioning for Cantaloupes and New Mexico chile type cultivars is limited. Such information is required to predict and identify critical stages of growth in order to develop efficient nutrient management programs for these crops. The goals of this dissertation are: 1) to obtain general irrigated cantaloupe and New Mexico chile plants development models as a function of heat units accumulated after planting (HUAP), and 2) to determine dry matter production and nutrient uptake and partitioning patterns of these crops as a function of HUAP. Four primary investigations are presented in this dissertation. In the first and second studies, plant development models for irrigated cantaloupe and New Mexico chile-type cultivars were obtained. For cantaloupe plants, early bloom occurred at 265 ± 47 HUAP, early fruit set at 381 ± 51 HUAP, early netting at 499 ± 63 HUAP, and physiological maturity at 746 ± 66 HUAP. For chile plants, first bloom occurred at 530 ± 141 HUAP, early bloom at 750 ± 170 HUAP, peak bloom at 1006 ± 145 HUAP, first green chile harvest at 1329 ± 120 HUAP, and red harvest stage at 1798 ± 58 HUAP. Also, these studies revealed that beyond the early netting stage (approximately 499 HUAP), cantaloupe fruits were the strongest sinks for dry matter accumulation. For chile plants, between the first green chile harvest and red chile harvest stages (approximately at 1550 HUAP), chile pods developed into stronger sinks for dry matter accumulation. The third and fourth investigations revealed that the period of maximum nutrient uptake coincides with that of maximum dry matter accumulation for both crops. The overall total nutrient uptake of N, P, K, Ca, Mg, S, B, Zn, Mn, Fe, and Cu for cantaloupe plants was 138, 21, 213, 132, 29, 28, 0.17, 0.20, 0.13, 2.0, and 0.06 kg ha⁻¹, for chile plants, the overall total nutrient was 216, 20, 292, 117, 56, 28, 0.31, 0.20, 0.31, 1.6 and 0.14 kg ha⁻¹ for these nutrients respectively.

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.

Study Objective. To assess the dietary intakes of children with Attention Deficit Hyperactivity Disorder (ADHD); including macro- and micronutrient intake, the percentage of low nutrient density foods in the diet, as well as specific biochemical and anthropometric parameters. Design. Observational study. Setting. Provincial ADHD Program of BC, Children’s’ Hospital, Vancouver, BC. Sample. 44 children aged 6 - 12 years with ADHD, treatment-naïve or stable on medication for 6 months or longer. Main Results. ADHD Children were taller and heavier than population norms, and significantly taller than previously reported in ADHD. Of children aged 6-8 years, 28% were below the Estimate Average Requirement (EAR) for zinc and 61% of children aged 9-12 years were below the EAR for zinc. In addition, 28% of children aged 6-8 years and 39% of children aged 9-12 years were below the EAR for copper. Only 2% of children in the sample were below lab normal cutoffs for ferritin; however, 73% had serum zinc values below lab normal cut-offs and 23% had serum copper below lab normal cutoffs. Overall prevalence of serum zinc below the 2.5 percentile was 23% compared to 2% from National Health and Nutrition Examination Survey II (NHANES) data. Additionally, mean serum copper was significantly lower than NHANES II data. Mean energy intake was comparable to mean Estimated Energy Requirement (EER) based on the age, gender, height, weight and physical activity of subjects. In addition, mean dietary intake of Low Nutrient Density foods was not significantly different from NHANES II data and there was no significant difference in energy intake or the proportion of daily energy from protein, fat, and carbohydrate than what is observed from CCHS data. Medication treatment for ADHD was not associated with altered dietary intake or nutrient status. Conclusion. Results are suggestive of low zinc status in ADHD.

Soil microbial communities can be characterized by community structure and function (community composition) across a spectrum of spatial scales, and variation in soil microbial composition has been associated with a number of environmental gradients. This study investigates the structure and function of soil microbial communities under mature, undisturbed forested sites across a range of regional climates in British Columbia and Alberta, and also examines the variation in community composition within sites. Phospholipid fatty acid analysis was used to investigate the structure of soil microbial communities and total soil microbial biomass at each site. Extra-cellular enzyme assays established the functional potential of the soil microbial community at each site. Multivariate analysis of the data showed that the soil microbial communities under different forest types did significantly separate along the regional climate gradient by both community structure and function, despite high local variation in the communities. Soil moisture content and soil organic matter concentration consistently exhibited the strongest relationship with microbial community characteristics, although the functional and structural responses to the external drivers were different. Microbial community function and structure also changed with soil depth but not with time of sampling. Microbial community function was related to the regional annual average precipitation gradient. Most of the locations exhibited unique microbial community functional profiles in their soil layers; however the enzyme activities in the samples from the driest (Ponderosa Pine) and wettest (Mountain Hemlock) locations were notably different from each other and from those of the other locations, especially in the organic layers. The moist maritime-influenced Coastal Western Hemlock (CWH) forest exhibited microbial community structural characteristics which were unique from those of the other forest locations. The higher abundance of bacteria relative to fungi in the CWH forest soils may be related to the significantly higher available nitrogen concentrations at this site.

The export of nitrogen (N) and phosphorus (P) from agricultural catchments is a major problem worldwide. The export of these nutrients is largely driven by storm events, and the hydrologic response of catchments varies within and between storm events. Antecedent soil moisture and rainfall rates have both been shown to affect the discharge and nutrient export from agricultural catchments, but their relationship to nutrient export is not fully understood. Currently, there are no studies that examine the leaching of both nitrate and phosphate from soil pools under the combined influence of differences in soil moisture and rainfall rates. The objectives of this study were to examine the combined effect of antecedent soil moisture and rainfall rates on the hydrologic response of soil and the export of nitrate and phosphate from the soil. The approach used intact soil monoliths in two experiments to first characterize the hydrologic response of the soil, and secondly to assess how the hydrologic response of the soil affects the leaching of nitrate and phosphate from soil pools. Differences in antecedent soil moisture and rainfall rates influenced both the amount of discharge and the hydrologic flow paths in the soil. As was expected, antecedent soil moisture governed the depth of discharge, with more discharge (runoff ratios= 0.89 to 0.91) produced by wet soil and the least runoff produced by dry soil (runoff ratios= 0.08 to 0.14) although this was not affected by the rainfall rate. Instead, rainfall rates predominantly affected hydrologic flow paths in the soil, with preferential flow at the beginning of the leaching period under high intensity rainfall (especially in wet soil), and predominantly matrix flow occurring under low intensity rainfall. The rainfall intensity did not appear to affect discharge volume. The mass of both nitrate and phosphate exported was higher under low intensity rainfall, ranging from 11.2 to 60.1mg/mU+00B2 and 77 to 4980μg/mU+00B2, respectively and from 0.9 to 34.4mg/mU+00B2 and 18.4 to 732μg/mU+00B2, respectively under high intensity rainfall. Antecedent soil moisture was significantly positively correlated with the depth of discharge produced, which also had a significant positive relationship with the mass of nitrate and phosphate exported (Spearman’s ρ= 0.75 to 0.81, p= <0.001), with greater masses of both nutrients exported from wet soil than dry soil. Soil moisture had contrasting influences on the nitrate concentrations in leachate, where nitrate concentrations and soil moisture were negatively related under low intensity rainfall and positively related under high intensity rainfall. Concentrations of phosphate in leachate were more variable, with no clear relationship to soil moisture, discharge, rainfall rate or soil phosphate pools. Antecedent soil moisture and the rainfall rate have a combined influence on the concentration of nitrate in leachate and an influence on the mass of both nitrate and phosphate exported. Although different hydrologic flow paths (matrix, preferential) were observed under the variable antecedent conditions and rainfall rates, this did not appear to affect nutrient fluxes from soil. This may be related to available nutrient pools and distributions in the soil in the current study. Understanding of the influence of flow types on the export of soil nutrient pools requires further study in a lab and a comparison of the breakthrough of nitrate and phosphate from soil pools with that of a conservative tracer (chloride). Nutrient and tracer breakthrough could then be compared to the hydraulic conductivity of the soil and the progression of the wetting front to fully understand the flow paths occurring and their effect on nutrient leaching.