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京都大学 / 新制・課程博士 / 博士(エネルギー科学) / 甲第23997号 / エネ博第433号 / 新制||エネ||82(附属図書館) / 京都大学大学院エネルギー科学研究科エネルギー社会・環境科学専攻 / (主査)教授 石原 慶一, 教授 白井 康之, 准教授 尾形 清一 / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DFAM

Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.

Diss. (sammanfattning) Uppsala : Univ., 2001. / Härtill 5 uppsatser.

The purpose of the following study was to re-address the energy requirements of Canadian Armed Forces (CAF) during training in a cold winter environment. Twenty CAF personnel were recruited to participate in a 5-day winter training exercise at Canadian Forces Base Meaford in Ontario, Canada. Energy expenditure (n=10) and body composition (n=14) were measured via the doubly labelled water (DLW) method and the deuterium isotope dilution technique, respectively. Mean total daily energy expenditure (TDEE) was 4900±693 kcal·day-1 with no significant differences observed between sexes. Body mass and body composition of CAF personnel changed significantly (p < 0.05) across the 5-day exercise. This decrease was associated with a significant (p < 0.05) reduction in fat mass. Despite these losses, participants were able to maintain high physical activity level (PAL) values (2.6) and high TDEE levels throughout the study period. It is recommended to increase the caloric content of the rations via additional supplements that provide energy-dense foods in bar format that can be easily consumed at the convenience of the individual. / February 2016

Snowpack energy balance in forest environment: spatial and temporal variability of shortwave and longwave radiation Assessment of the role of forest on snowmelt processes and snowpack attributes contributes to the accuracy of spring floods forecasting. An importance of the coniferous forest consists in change of the snowpack energy balance. Forest reduces the total amount of solar radiation, however trees cause emitting of longwave radiation, both factors are fundamentally reflected in time of snowmelt in forest environment. Master thesis focuses on temporal and spatial variability of shortwave and longwave radiation depending on the structures of vegetation cover. Individual site types were defined as an open area, a forest affected by the bark beetle (Ips typographus) and a healthy coniferous forest, based on the hemispheric images of vegetation and its Leaf Area Index (LAI). Moreover, repeated manual measurements of the snow depth and snow water equivalent (SWE) were done in plots during winter period 2016/2017 in the Ptačí Brook catchment in the Šumava Mountains, and an analysis of shortwave and longwave radiation data the radiometers in plots was performed. Radiation fluxes in different plots were described in daily and seasonal scale, including the calculation of total heat from shortwave and...

Introduction: Obesity has become a major world-wide health issue. Social-economic status, physical activity levels and dietary intake may influence the weight status in children. However, these issues have not been examined together in studies of young girls in Saudi Arabia. Aim: This study aimed to investigate energy and nutrient intakes, physical activity and social economic status of girls aged 8-11 years in western Saudi Arabia according to their BMI. Methods: This study was conducted in two phases, phase one was a pilot study where 32 girls were selected to assess the suitability of body composition, dietary intake (food diary, food frequency questionnaire) and physical activity measurement tools (pedometer, physical activity questionnaire). The findings of this phase were employed in phase 2; the diet diary and accelerometer were nominated as assessment tools. In phase two, girls (n= 234) participated from different schools. Waist circumference, height and weight were measured and BMI was calculated. Girls were classified according to BMI centile charts (CDC). Dietary intake was measured via a 4-day food diary and accelerometers were used to assess the intensity and time spent in physical activity. Results: A total of 30% of the sample were classified obese or overweight. There was a significant difference in the mean daily energy intake between the BMI groups with the obese group having the highest energy, fat, carbohydrate and protein intake (obese group: 2677 ± 804 kcal/d; healthy weight group: 1806 ± 403 kcal/d, p< 0.001), but the percentage contribution of the macronutrients to energy intake remained the same across the BMI groups. Carbohydrate intake was shown to be the main contributor to predict obesity levels. VI There were no differences in number of steps taken per day or time spent in moderate/ vigorous intensity exercise according to BMI category. Most of the girls did not meet daily physical activity guidelines (5969 to 6773 steps per day and 18.5 - 22.5 mins per day of moderate- vigorous activity). Intake of sweets and sugary drinks, and total energy intake were significantly higher in the high income group compared to the low income group. However, family income was not associated with BMI status. Conclusion: The results of this study suggest that obesity in girls aged 8-11 years is linked to excessive energy intake from all macronutrients and the majority of girls in all weight categories are inactive. Research should be conducted to develop interventions to promote dietary change and activity that is culturally acceptable for girls in Saudi Arabia.

Ce travail a permis de modéliser le bilan de masse superficiel sur le bassin versant du Glacier 15 du massif Antisana (0.28 km2; 0°28'S, 78°09'W), dans les Andes tropical de l'Equateur. Le bilan de masse superficiel (MBS) entre 2000 et 2008 sur le glacier 15a de l'Antisana a été modélisé en utilisant deux approches parallèles : un modèle empirique de type degré-jour et un modèle physique de type bilan d'énergie.Dans un premier temps, la fonte a été calculée à l'aide de la température moyenne et des cumuls de précipitations alors que le calcul de la sublimation a été réalisé grâce à la vitesse du vent. Ce modèle a été appliqué au pas de temps journalier et a été calé à 4900 m d'altitude entre mars 2002 et août 2003 et validé entre janvier et novembre 2005. Un lien significatif entre la température et la fonte apparaît lorsqu'une distinction entre neige et glace est effectuée. La relation entre la fusion et la température est expliquée essentiellement par le lien significatif existant entre le bilan radiatif de courtes longueurs d'onde et la température, car le rayonnement solaire est aussi le principal moteur de la fonte. Néanmoins, cette relation disparaît dès lors que le vent devient intense. Ce point a cependant peu de conséquences sur les calculs effectués, car les périodes ventées sont marquées par des températures faibles. Le modèle a été appliqué pour évaluer dans quelle mesure cette approche est appropriée pour modéliser le bilan de masse superficiel, l'ablation, et les altitudes de la ligne de neige et de la ligne d'équilibre. Les résultats montrent qu'un modèle empirique de type degré-jour permet une modélisation précise du MBS à l'échelle d'un glacier en Equateur. Néanmoins, ce modèle ne devrait pas être appliqué à d'autres régions tropicales, en particulier là où la sublimation est importante (grâce à une saison sèche prononcée) ou lorsque les glaciers sont situés au-dessus de l'altitude moyenne de l'isotherme 0°C.Dans un deuxième temps, un modèle de bilan d'énergie superficiel (BES) distribué développé initialement pour des applications en Terre d'Adélie (Antarctique) a été appliqué sur le site du glacier 15a de l'Antisana pour quantifier l'ablation de la glace et de la neige. Ce modèle a été adapté pour les conditions tropicales puis forcé à l'aide des mesures météorologiques obtenues à proximité et sur glacier 15a. Le modèle a tout d'abord été appliqué à une altitude de référence à 4900 m pour une pente de 28° et avec un azimut NO (45°). La spatialisation du bilan d'énergie a ensuite été effectuée en discrétisant le glacier par tranches de 50 m d'altitude, puis en calculant la pente et l'azimut moyen de chaque tranche à l'aide de un modèle numérique de terrain (MNT) précis du glacier. Les données d'entrées ont été distribuées sur la langue du glacier 15a en supposant que les forçages météorologiques varient selon des gradients verticaux constants. Ces gradients ont été établis à partir de mesures de terrain. Le modèle a été calé à partir des données de bilan de masse mensuel et d'albédo journalier mesurées sur le glacier 15a entre mars 2002 et août 2003, puis validé à partir de mesures obtenues entre janvier 2005 et décembre 2008. Le modèle reproduit précisément les variations spatiales et temporelles du bilan de masse entre 4850 m et 5700 m d'altitude. Les résultats inédits de bilan d'énergie de surface distribués sur le glacier 15a ont ainsi permis d'analyser les processus physiques à l'origine des variations spatio-temporelles de l'ablation. Enfin, cette étude explique pour la première fois pourquoi les modèles de type degré-jour donnent systématiquement des résultats de bonne qualité dans cette région, venant contredire les résultats d'études antérieures. Cette thèse constitue ainsi une étape importante dans la compréhension de la sensibilité des bilans de masse aux variations de température dans cette région. / Antisana Glacier 15 basin surface mass balance (SMB) (0.28 km2;0°28'S,78° 09'W, 5750 m), located in the tropical Andes of Ecuador, between 2000 and 2008 has been modeled using two models: an empirical positive degree-day (PDD) and other physical surface energy balance approach..As a first stage, melting was calculated using daily temperature and the cumulative precipitation while sublimation was computed as wind-speed function. The PDD was applied at daily-time step and calibrated at 4900 m a.s.l. The period time to calibrate was March 2002 - August 2003 and validated was January - November 2005. A significant link between melting rates and temperature was revealed when model discriminates snow and ice surface. This relationship is explained by the link between the short-wave radiation and air temperature. However, this relationship disappears under intense wind-speed events, however this events show low air temperature, therefore they are not affect the final results. The PDD model was applied for modeling SMB, ablation, snow-line position and equilibrium line altitude. The results show this model type fits to SMB measures over Antisana glacier. However, it should not apply to other tropical regions, particularly where there are high sublimation rates (pronounced dry seasons) or where glaciers are located under the isotherm 0 ° C.A second stage, a distributed surface energy balance (DBES) model over glacier 15a of the Antisana was applied to quantify ice and snow ablation. For this task was used a model adapted to tropical conditions from Adélie Land-Antarctica BES model. Initially, the model was applied at 4900 m.a.s.l. , with a slope of 28º and NW (45 °) azimuth. For computing DBES, the glacier was divided in 18 altitude strips ( 50m/level). The model generated slops and azimuths from a digital elevation model (DEM). The meteorological vertical gradients were measured in the study zone. This values was used into de model as constants during both periods calibration and validation. The DBES model reproduced the spatial variation and temporal of SMB between 4850 m.a.s.l. and 5700 m.a.s.l.. The unpublished results of SEB distributed on the glacier 15a allowed to analyze the physical processes that to generate the spatio-temporal variation of the ablation.The DBES results show that the model applied in a former research was based on wrong assumptions and inaccurate. The results of DBES and PDD models show that the accumulated precipitation measured at the bottom of the glacier are greatly underestimated. It implies the need for new protocols for improving the precipitation measurement. Both the former research and SEB confirm the crucial role of shortwave radiation and albedo values over glacier melt. It puts also in evidence that snow metamorphism in the study zone occurs faster than other latitudes, associated with accelerated degradation of surface albedo. Finally, this research explains the reason why the PDD model provides good quality results in this region, which contradicted the results of previous study. This research contributes a better understanding about sensibility of SMB with temperature variations in the inner tropics.

abstract: The North American Monsoon System (NAMS) contributes ~55% of the annual rainfall in the Chihuahuan Desert during the summer months. Relatively frequent, intense storms during the NAMS increase soil moisture, reduce surface temperature and lead to runoff in ephemeral channels. Quantifying these processes, however, is difficult due to the sparse nature of coordinated observations. In this study, I present results from a field network of rain gauges (n = 5), soil probes (n = 48), channel flumes (n = 4), and meteorological equipment in a small desert shrubland watershed (~0.05 km2) in the Jornada Experimental. Using this high-resolution network, I characterize the temporal and spatial variability of rainfall, soil conditions and channel runoff within the watershed from June 2010 to September 2011, covering two NAMS periods. In addition, CO2, water and energy measurements at an eddy covariance tower quantify seasonal, monthly and event-scale changes in land-atmosphere states and fluxes. Results from this study indicate a strong seasonality in water and energy fluxes, with a reduction in Bowen ratio (B, the ratio of sensible to latent heat fluxes) from winter (B = 14) to summer (B = 3.3). This reduction is tied to shallow soil moisture availability during the summer (s = 0.040 m3/m3) as compared to the winter (s = 0.004 m3/m3). During the NAMS, I analyzed four consecutive rainfall-runoff events to quantify the soil moisture and channel flow responses and how water availability impacted the land-atmosphere fluxes. Spatial hydrologic variations during events occur over distances as short as ~15 m. The field network also allowed comparisons of several approaches to estimate evapotranspiration (ET). I found a more accurate ET estimate (a reduction of mean absolute error by 38%) when using distributed soil moisture data, as compared to a standard water balance approach based on the tower site. In addition, use of spatially-varied soil moisture data yielded a more reasonable relationship between ET and soil moisture, an important parameterization in many hydrologic models. The analyses illustrates the value of high-resolution sampling for quantifying seasonal fluxes in desert shrublands and their improvements in closing the water balance in small watersheds. / Dissertation/Thesis / M.S. Civil and Environmental Engineering 2011

Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-10-08T13:59:24Z No. of bitstreams: 1 ANECLÉIA RODRIGUES DE LIMA - DISSERTAÇÃO (PPGRN) 2011.doc: 7132672 bytes, checksum: 6ba8998cfd7769b657914feb266b8475 (MD5) / Made available in DSpace on 2018-10-08T13:59:24Z (GMT). No. of bitstreams: 1 ANECLÉIA RODRIGUES DE LIMA - DISSERTAÇÃO (PPGRN) 2011.doc: 7132672 bytes, checksum: 6ba8998cfd7769b657914feb266b8475 (MD5) Previous issue date: 2011-03-01 / Capes / A presente pesquisa foi conduzida em nível de campo na Fazenda Experimental da Empresa de Pesquisa Agropecuária do Rio Grande do Norte – EMPARN, localizada no município de Apodi, RN. Foram utilizados na determinação do consumo hídrico da cultura do feijão caupi irrigado os métodos de Penman-Monteith para estimar a evapotranspiração de referencia (ETo), balanço de energia baseado na razão de Bowen para estimar a ETc e a relação ETc/ETo para determinar o coeficiente de cultivo (Kc). O experimento foi realizado utilizando uma parcela experimental de 4,0 ha cultivado com feijão caupi, cultivar Potiguar, com espaçamento de 70 cm entre linhas e uma densidade populacional de aproximadamente 4 plantas m-1. O sistema de irrigação foi por aspersão, considerando uma eficiência de 60%, o que totalizou uma lâmina de irrigação de 463,7 mm ao final do ciclo da cultura. Os resultados evidenciam que o consumo hídrico da cultura do feijão-caupi foi maior na fase de desenvolvimento vegetativo (166,91 mm), enquanto que para todo o ciclo o consumo foi 431,86 mm; Comparando os sistemas irrigado e de sequeiro na produção de feijão-caupi, o sistema irrigado alcançou uma rentabilidade superior. Assim, o cultivo irrigado do feijão-caupi na região de Apodi, RN, é economicamente viável, pois a renda líquida com o cultivo irrigado foi superior a renda líquida obtida pelo cultivo em sistema de sequeiro. / This study was carried out under field conditions at the Experimental Farm of the Agricultural Research Company of Rio Grande do Norte (EMPARN), in Apodi, RN. For determining the crop water consumption of cowpea irrigated, it was used the methods of Penman-Monteith to estimate reference evapotranspiration (ETo), energy balance based on Bowen ratio to estimate crop evapotranspiration (ETc) and the ratio ETc/ETo to determine the crop coefficient (Kc). The experiment was conducted using an experimental plot of 4.0 ha cultivated with cowpea cultivar Potiguar, with 70 cm between rows which resulted a density of 4 plants m-1. The irrigation system sprinkler was used with an efficiency of 60%, which produced a water depth of 463.7 mm at the end of the cycle. The results show that the water requirement of cowpea was higher in the period of vegetative growth (166.91 mm), while for the entire cycle it was 431.86 mm.