Mixed grasslands in south Canada serve a variety of economic, environmental and ecological purposes. Numerical modeling has become a major method used to identify potential grassland ecosystem responses to environment changes and human activities. In recent years, the focus has been on process models because of their high accuracy and ability to describe the interactions among different environmental components and the ecological processes. At present, two commonly-used process models (CENTURY and BIOME-BGC) have significantly improved our understanding of the possible consequences and responses of terrestrial ecosystems under different environmental conditions. However, problems with these models include only using site-based parameters and adopting different assumptions on interactions between plant, environmental conditions and human activities in simulating such complex phenomenon. In light of this shortfall, the overall objective of this research is to integrate remote sensing products into ecosystem process model in order to simulate productivity for the mixed grassland ecosystem in the landscape level. Data used includes 4-years of field measurements and diverse satellite data (System Pour lObservation de la Terre (SPOT) 4 and 5, Landsat TM and ETM, Advanced Very High Resolution Radiometer (AVHRR) imagery). <p>Using wavelet analyses, the study first detects that the dominant spatial scale is controlled by topography and thus determines that 20-30 m is the optimum resolution to capture the vegetation spatial variation for the study area. Second, the performance of the RDVI (Renormalized Difference Vegetation Index), ATSAVI (Adjusted Transformed Soil-Adjusted Vegetation Index), and MCARI2 (Modified Chlorophyll Absorption Ratio Index 2) are slightly better than the other VIs in the groups of ratio-based, soil-line-related, and chlorophyll-corrected VIs, respectively. By incorporating CAI (Cellulose Absorption Index) as a litter factor in ATSAVI, a new VI is developed (L-ATSAVI) and it improves LAI estimation capability by about 10%. Third, vegetation maps are derived from a SPOT 4 image based on the significant relationship between LAI and ATSAVI to aid spatial modeling. Fourth, object-oriented classifier is determined as the best approach, providing ecosystem models with an accurate land cover map. Fifth, the phenology parameters are identified for the study area using 22-year AVHRR data, providing the input variables for spatial modeling. Finally, the performance of popular ecosystem models in simulating grassland vegetation productivity is evaluated using site-based field data, AVHRR NDVI data, and climate data. A new model frame, which integrates remote sensing data with site-based BIOME-BGC model, is developed for the mixed grassland prairie. The developed remote sensing-based process model is able to simulate ecosystem processes at the landscape level and can simulate productivity distribution with 71% accuracy for 2005.

A growing body of literature has drawn attention to the ways in which contemporary education reforms are changing how teachers perform their work, but less attention has been paid to what this means for particular social contexts, including the schools and communities attempting to improve learning for Aboriginal peoples. Teachers are increasingly subject to the dynamics of the global economy, and citizens expectations that public schools can solve social and economic problems. Governments have demanded too much from schools and educators given their capacity to be both more productive in education, and to provide more social care than before to Aboriginal students and families, while at the same time achieving the improvement of educational attainment for Aboriginal children and youth. Educational researchers suggest there is evidence that global-productivity and local-community imperatives are contradictory objectives in educational change. Despite the resources and attention given to Aboriginal education, and a more recent resurgence in support for elementary and secondary schooling, teachers have known for some time that citizens expectations are goliath in comparison to the actual resources that schools have at their disposal for educational improvement. In contrast with the lack of attention given to educators perspectives in literature on school reform, teachers are identified in critical analysis within the sociology of education as key agents crucial to the actualisation of educational improvement for Aboriginal peoples This thesis draws on data from a number of studies pertaining to teachers work in Aboriginal communities, conducted between 2002 and 2005, to determine:<p> What do teachers, working in Aboriginal communities located in Saskatchewan, identify as the main factors driving their work? <p> According to teachers, how are the main factors driving their work affected by policies to improve education for Aboriginal students in Saskatchewan?<p> How, if at all, are educators managing to balance the seemingly oppositional policy and program logics of productivity and community while attempting to achieve educational improvement for Aboriginal students in Saskatchewan?<p> Informed by teachers perspectives regarding their work in Aboriginal communities, I argue that teachers working in cross cultural contexts, and where governments share jurisdiction over education with Indigenous peoples, may undergo changes in their professionalism which situates them as cultural mediators in the community. Teachers may mediate between the competing demands of governments, parents, students, and even the demands of competing policy and program logics intended, when combined to improve Aboriginal peoples educational outcomes.

Two trials were conducted with the objective of investigating the effect of light intensity, approximately within the practical levels at confinement barns (1, 10, 20 and 40 lx), on production, processing characteristics and welfare of broilers raised to 35 d of age. In each trial, 950 Ross x Ross 308 chicks were placed randomly in each room with replication of individual light intensity treatment in two environmentally controlled experimental rooms. Within each large room, a small pen with 25 male and 25 female chicks was used for recording behaviour. Data were analyzed as a randomized complete block design, considering trial as a block. All chicks were exposed to 40 lx light intensity and 23 h light for the first 7 d, followed by treatment light intensity and 17 h day length thereafter. Body weight and feed consumption were determined at 7, 14, and 35 d of age. At the conclusion of each trial, 60 birds per treatment were processed to determine the detailed meat yield. For each replicate, behaviour was recorded for the 24 h period, starting at 16 or 17 d of age. At 23 d of age, serum samples were collected from three birds per room at the start, middle and end of light and dark periods, respectively, for melatonin estimation. Skeletal and foot pad, and ocular health were monitored at 31 and 32 d of age, respectively. Broiler live production (BW, FC, FCR and mortality) was unaffected by light intensity. Carcass, thigh and drum yield as a percentage of live weight decreased linearly with increasing light intensity. The 1 lx treatment resulted in heavier wings as a percentage of live weight. Birds exposed to 1 lx rested more and had reduced expression of foraging, preening, dust-bathing, stretching and wing-flapping behaviours in comparison to other light intensities, over the 24 h period and 17 h light phase. Light intensity did not affect circadian behavioural rhythms (24 h period) and behavioural patterns over the 17 h light phase. Diurnal rhythms of serum melatonin were also unaffected by light intensity with all treatments demonstrating a pronounced rhythm. Skeletal health was unaffected by light intensity but ulcerative foot pad lesions decreased linearly with increasing light intensity. Birds exposed to the 1 lx intensity had heavier and larger eyes. In conclusion, light intensity did not affect broiler production, behavioural and physiological rhythms and mortality but did affect carcass characteristics. Increased ulcerative foot pad lesions, ocular dimensions and altered behavioural expression at 1 lx light intensity are indicators of reduced broiler welfare.

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In this dissertation, I study the effects of climate change on agricultural total factor productivity and crop yields and their variability. In addition, an examination was conducted on the value of select climate change adaptation strategies in forestry. Across the study, the climate change scenarios analyzed were based on the 2007 Intergovernmental Panel on Climate Change Assessment Report. Climate change impacts on the returns to research investments were examined extending the work of Huffman and Evenson (2006), incorporating climatic effects. The conjecture is that the rate of return of agricultural research is falling due to altered resource allocations and unfavorable weather conditions, arising from the early onset of climate change. This work was done using a panel model of Agricultural Total Factor Productivity (TFP) for the forty-eight contiguous states over 1970?1999. Climatic variables such as temperature and amount and intensity of precipitation were added into the model. The main results are (1) climate change affects research productivity, varying by region; (2) this effect is generally negative; (3) additional investments are needed to achieve pre-climate change TFP rates of growth; and (4) the predicted investment increases are on the order of 18%. The second inquiry involved the impact of historical climatic conditions on the statistical distributions of crop yields through mean and variability. This was done statistically, using historical yields for several crops in the US, and climate variables, with annual observations from 1960 to 2007. The estimation shows that climate change is having an effect on the first two moments of the distribution, concluding that crop yield distributions are not stationary. The implication is that risk analysis must consider means and volatility measures that depend on future climatic conditions. The analysis shows that future mean yields will increase, but volatility will also be greater for the studied crops. These results have strong implication for future crop insurance decisions. Finally, an examination was done on the value of select forestry adaptation strategies in the face of climate change. This work is motivated by the known fact that forestry sector is already heavily adapted to changing climatic conditions. Using the Forestry and Agriculture Sector Optimization Model for the United States (FASOM), I found that rotation age is the most effective adaptation strategy being worth about 60 billion dollars, while changes in species and management intensity are worth about 1.5 billion, and land use change between forestry to agriculture is worth about 200,000.

Data were analyzed on 2 to 6 yr old cows to evaluate sire and family effects. Cows were produced in the McGregor Genomics Project from 13 embryo transfer (ET) full sib families (n = 188, F2 Nellore-Angus (NA)) and 4 half sib natural service (NS) families (n = 114, out of 1/2 Brahman 1/2 British dams) from the same 4 F1 NA sires. The ET and NS cows were analyzed separately and together as paternal half sibs (PHS). Daughters of bull 437J had the highest calving rate and weaning rate; daughters of 551G were the lowest in ET, and daughters of 297J were the lowest in NS. Calves out of daughters of 551G were the heaviest at birth; those from of daughters of 437J were the lightest in NS and PHS. Calves out of daughters of 297J were the heaviest at weaning in ET and PHS, and those from daughters of 432H were the lightest. Calves from daughters of 297J and 437J gained the most weight and those from daughters of 432H gained the least. Daughters of 297J and 551G had longer and larger diameter teats and lower udder support scores (more pendulous) than daughters of 432H and 437J. Daughters of 437J had the highest body condition score (BCS); daughters of 551G were the lowest in ET and NS. Calves from daughters of 297J had the highest BCS at weaning. Those out of daughters of 551G had the lightest WWT, those out of daughters of 437J were the heaviest in NS and PHS, and those out of daughters of 432H were the heaviest in ET. Daughters of 437J and 551G scored the highest for disposition (least docile) in ET and PHS, and daughters of 432H were lowest. The regression of WWT on weaning age was 0.82 plus/minus 0.07 in ET, 0.71 plus/minus 0.08 in NS, and 0.78 plus/minus 0.05 kg/d in PHS. There appears to be sufficient variation within and between these full sib and half sib families for use in QTL analysis for major genes affecting cow productivity in NA crosses.

The focus of this paper is to discuss the relationship between organizational changes and information communication technology (ICT) in Taiwan semiconductor industry. Besides, we also examine the effect of ICT adoption workforce on productivity and organizational change. In this paper, our organizational change includes electronics ICT and manpower saving cost. We develop a treatment effect to estimate organizational change. Electronics ICT adoption leads organizational change and then causes firms to employ less low-skilled labors. Organizational change also makes productivity growth further in semiconductor industry.

The contribution of phytoplankton productivity to higher trophic levels in salt marshes is not well understood. My study furthers our understanding of possible mechanisms controlling phytoplankton productivity, abundance, and community composition in salt marshes. Across three consecutive springs (2001 to 2003), I sampled the upper Nueces Delta in south Texas, a shallow, turbid, salt marsh system stressed by low freshwater inflow and wide ranging salinity (<15 to >300 ppt). Water column productivity and respiration were estimated using a light-dark bottle technique, and phytoplankton biovolume and community composition were determined using inverted light microscopy. To determine their effect on the phytoplankton community, zooplankton and bacterioplankton abundance and several physical parameters were also assessed. Meaningful relationships among the numerous variables evaluated in this study were identified using principal component analysis (PCA). Despite high turbidity, phytoplankton productivity and biovolume were substantial. Resuspension appeared to play a major role in phytoplankton dynamics, as indicated by a positive relationship between ash weight and biovolume that explained up to 46% of the variation in the PCA. Negative relationships between zooplankton grazers and pennate diatoms of optimal sizes for these grazers suggested a functional grazing food chain in this system. Salinity also may have been important in phytoplankton dynamics, whereas nutrients appeared to play a minor role. Salinity increases may have been responsible for a decoupling observed between phytoplankton and grazers during late spring. Findings suggest hypotheses for future studies focused on the role of phytoplankton in salt marshes, particularly those stressed by reduced freshwater inflow and high salinities.

Reproductive and weight traits were analyzed for Angus (A), Brahman (B), Hereford (H), and Nellore (N) straightbred cows; F1 NA cows; 3/8N 5/8A cows and quarter blood composite cows (BANH) of the four straightbreds in Central Texas. Heterosis was estimated for calf crop born (CCB), calf crop weaned (CCW), and calf survival (CS) by linear contrasts within cow breed groups. F1 NA cows expressed heterosis (P < 0.0001) for CCB (0.22) and CCW (0.20). Except for the 3/8N 5/8Ac cows, which resulted from the mating of NA bulls to 3/4A 1/4N cows, all of the crossbred cow breed types expressed significant heterosis (P < 0.05) when compared to the weighted average of the parental purebreds for CCB. BANHc cows that were the result of mating NA bulls to HB cows expressed heterosis for CCB (0.35) (P < 0.001) and CCW (0.29) (P < 0.05). The 3/8N 5/8Aa females produced by mating 3/4N 1/4A bulls to NA cows expressed heterosis (P < 0.0001) for CCW (0.20). Heterosis for calf survival was near zero for all breed types, but only two breed types of 3/8N 5/8A cows were significantly greater than the weighted average of the parental purebreds. Heterosis for birth weight (BWT) and weaning weight (WWT) was also analyzed by linear contrasts within cow breed groups. The BANHb and BANHc cows produced from mating NA bulls to BH and HB F1 cows, respectively, expressed heterosis for BWT (2.89 + 0.79 (P < 0.001) and 3.38 + 1.51 (P < 0.05)). All cow breed types expressed significant heterosis (P < 0.05) for WWT. The BANH2 cows resulting from the mating of NA bulls to F2 HB or BH cows expressed heterosis (P < 0.0001) for WWT (52.01 kg + 9.88).

Sire and family effects were evaluated for calf growth, udder and teat conformation, and reproduction traits in 2- to 4- yr-old cows from the McGregor Genomics Project. Cows were produced by embryo transfer (ET) and natural service (NS) from the same 4 F1 Nellore-Angus sires, and were analyzed separately. Sire of cow was significant for calf birth weight (P = 0.014) among ET cows, but not NS cows. Among NS families, calves from cows out of Brahman-Hereford dams were 2.0 kg heavier (P = 0.064) at birth than calves from cows out of Brahman-Angus dams. Sire of cow accounted for variation in weaning weight (P = 0.006) and preweaning ADG (P = 0.005) of calves from ET dams, but not NS dams. Family nested within sire also accounted for variation (P = 0.061) in weaning weights of calves from ET dams. Sire of cow was significant for average teat length in ET (P < 0.001) and NS (P = 0.013) cows. Sire of cow was significant for average teat diameter (P = 0.022) among NS cows. Sire of cow also affected udder support score (P = 0.002), cow disposition at calf birth (P = 0.002), and cow weight at weaning (P = 0.045) in ET cows. Family and cow age also accounted for variation in cow disposition at calf birth (P = 0.015, P = 0.041, respectively) and cow weight at weaning (P = 0.001, P < .001, respectively) among ET cows. Calf year of birth also affected (P < .001) cow weight at weaning among ET cows. For NS dams, calf year of birth (P = 0.012), cow age (P < .001), and parity nested within cow age (P = 0.005) affected cow weight at weaning. Although reproduction data were not formally analyzed, there appear to be substantial differences for calving rate and average calving date among these cow families. Data from this project will be used for identification of genetic markers for these cow productivity traits.