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Applicability of satellite and NWP precipitation for flood modeling and forecasting in transboundary Chenab River Basin, PakistanAhmed, Ehtesham 11 April 2024 (has links)
This research was aimed to evaluate the possibility of using satellite precipitation products (SPPs) and Numerical Weather Prediction (NWP) of precipitation for better hydrologic simulations and flood forecasting in the trans-boundary Chenab River Basin (CRB) in Pakistan. This research was divided into three parts.
In the first part, two renowned SPPs, i.e., global precipitation mission (GPM) IMERG-F v6 and tropical rainfall measuring mission (TRMM) 3B42 v7, were incorporated in a semidistributed hydrological model, i.e., the soil and water assessment tool (SWAT), to assess the daily and monthly runoff pattern in Chenab River at the Marala Barrage gauging site in Pakistan. The results exhibit higher correlation between observed and simulated discharges at monthly timescale simulations rather than daily timescale simulations. Moreover, results show that IMERG-F is superior to 3B42 by indicating higher R2, higher Nash–Sutcliffe efficiency (NSE), and lower percent bias (PBIAS) at both monthly and daily timescale.
In the second part, three latest half-hourly (HH) and daily (D) SPPs, i.e., 'IMERG-E', 'IMERGL', and 'IMERG-F', were evaluated for daily and monthly flow simulations in the SWAT model. The study revealed that monthly flow simulation performance is better than daily flow simulation in all sub-daily and daily SPPs-based models. Results depict that IMERGHHF and IMERG-DF yield the best performance among the other latency levels of SPPs. However, the IMERG-HHF based model has a reasonably higher daily correlation coefficient (R) and lower daily root mean square error (RMSE) than IMERG-DF. IMERG-HHF displays the lowest PBIAS for daily and monthly flow validations and it also represents relatively higher values of R2 and NSE than any other model for daily and monthly model validation. Moreover, the sub-daily IMERG based model outperformed the daily IMERG based model for all calibration and validation scenarios. IMERG-DL based model demonstrates poor performance among all of the SPPs, in daily and monthly flow validation, with low R2, low NSE, and high PBIAS. Additionally, the IMERG-HHE model outperformed IMERG-HHL.
In the third and last part of this research, coupled hydro-meteorological precipitation information was used to forecast the 2016 flood event in the Chenab River Basin. The gaugecalibrated SPP, i.e., Global Satellite Mapping of Precipitation (GSMaP_Gauge), was selected to calibrate the Integrated Flood Analysis System (IFAS) model for the 2016 flood event. Precipitation from the Global Forecast System (GFS) NWP, with nine different lead times up to 4 days, was used in the calibrated IFAS model. This study revealed that the hydrologic simulations in IFAS, with global GFS forecasts, were unable to predict the flood peak for all lead times. Later, the Weather Research and Forecasting (WRF) model was used to downscale the precipitation forecasts with one-way and two-way nesting approaches. It was found in this study that the simulated hydrographs in the IFAS model, at different lead times, from the precipitation of two-way WRF nesting exhibited superior performance with the highest R2, NSE and the lowest PBIAS compared with one-way nesting.
Moreover, it was concluded that the combination of GFS forecast and two-way WRF nesting can provide high-quality precipitation prediction to simulate flood hydrographs with a remarkable lead time of 96 h when applying coupled hydrometeorological flow simulation.
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The potential of Russia to increase its wheat production through cropland expansion and intensificationSchierhorn, Florian 18 November 2015 (has links)
Die vorrangige Zielstellung dieser Dissertation war die Berechnung nicht erschlossener landwirtschaftlicher Potenziale des Europäischen Russlands. Wir haben ein räumliches Allokationsmodell entwickelt, dass die jährlichen Acker- und Ackerbrachflächen von 1991 bis 2009 kartiert. Diese Daten haben wir anschließend in ein dynamisches Vegetationsmodell integriert und damit berechnet, dass während der postsowjetischen Aufgabe von 31 Millionen Hektar Ackerland bis 2009 470 TgC in Boden und Vegetation gebunden wurden. Anschließend haben wir ein Pflanzenwachstumsmodell auf regionale Weizenerträge kalibriert und darauf basierend durchschnittliche Ertragslücken von 1.51-2.10 t ha−1 für natürliche (künstlich unbewässerte) und 3.14-3.30 t ha−1 für künstlich bewässerte Anbaubedingungen ermittelt. Die Karte der Ackerbrachflächen, räumlich-explizite Informationen über die Kohlenstoffspeicherung in Boden und Vegetation infolge der Ackerflächenaufgabe sowie unsere Ergebnisse der Ertragslückenberechnung haben wir zur Berechnung von Weizenproduktionspotenzialen verwendet. Unsere Ergebnisse zeigen, dass das Europäische Russland erhebliche Potenziale mobilisieren kann – bis zu 32 Millionen Tonnen für künstlich unbewässerte Bedingungen – obwohl ausschließlich jüngere Ackerbrachen zur Rekultivierung in unserem Modell berücksichtigt wurden. Ältere Brachflächen haben häufig große Mengen Kohlenstoff in Boden und Vegetation gespeichert; die Rekultivierung ältere Brachflächen würde zu hohen Emissionen führen. Eine wesentliche Schlussfolgerung dieser Dissertation ist daher, dass Produktionssteigerungen vorrangig durch Flächenintensivierung der bestehenden Ackerflächen erzielt werden sollten. Allerdings können die Ergebnisse dieser Arbeit helfen, Brachen für die Rekultivierung zu bestimmen, deren Rekultivierung relativ geringe Kohlenstoffemissionen nach sich ziehten. Zudem können die Ergebnisse dieser Arbeit nützlich sein, landwirtschaftliche Produktionsmittel effizienter einzusetzen. / This dissertation addresses the primary objective to systematically quantify untapped agricultural potentials in European Russia, where widespread abandoned agricultural lands and large yield gaps co-exist. We developed a spatial allocation model to produce annual cropland and cropland abandonment maps. Feeding the new maps into a dynamic vegetation model revealed that 470 Tg of carbon was sequestered in soil and vegetation due to the abandonment of 31 million hectares of cropland. Thus, the environmental consequences limit the potential for cropland expansion to abandoned cropland. We then calibrated a crop growth model for provincial wheat yields in European Russia and found average yield gaps of 1.51–2.10 t ha−1 under rainfed conditions and 3.14–3.30 t ha−1 under irrigated conditions. The cropland abandonment maps, spatial information on carbon sequestration due to cropland abandonment, and the estimates of yield gaps allowed us to estimate the potential of European Russia to increase its wheat production and to account for the carbon tradeoffs of cropland expansion. We demonstrated that European Russia can substantially increase its wheat production (up to 32 Mt under rainfed conditions). This increase is despite a limited expansion of wheat cultivation to the recently abandoned cropland to reduce the trade-off from the high carbon emissions in re-cultivating older, abandoned cropland where most carbon is stored. Therefore, intensification of the existing croplands is recommended to be the major driver for future growth in agricultural production. This dissertation can help policy makers and agribusiness owners identify areas suitable for cropland expansion, better target agricultural inputs and infrastructures, as well as guide adaptation strategies to the volatile climate conditions. Moreover, this dissertation contributes to better identifying and balancing trade-offs between environmental impacts and increasing agricultural production in European Russia.
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Potential climate change impacts on hydrologic regimes in northeast KansasSiebenmorgen, Christopher B. January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Kyle R. Douglas-Mankin / The Great Plains once encompassed 160 million hectares of grassland in the central United States. In the last several decades, conversion of grassland to urban and agricultural production areas has caused significant increases in runoff and erosion. Past attempts to slow this hydrologic system degradation have shown success, but climate change could once again significantly alter the hydrology. The Intergovernmental Panel on Climate Change (IPCC) studies the state of knowledge pertaining to climate change. The IPCC has developed four possible future scenarios (A1, A2, B1 and B2). The output temperature and precipitation data for Northeast Kansas from fifteen A2 General Circulation Models (GCMs) were analyzed in this study. This analysis showed that future temperature increases are consistent among the GCMs. On the other hand, precipitation projections varied greatly among GCMs both on annual and monthly scales. It is clear that the results of a hydrologic study will vary depending on which GCM is used to generate future climate data. To overcome this difficulty, a way to take all GCMs into account in a hydrologic analysis is needed. Separate methods were used to develop three groups of scenarios from the output of fifteen A2 GCMs. Using a stochastic weather generator, WINDS, monthly adjustments for future temperature and precipitation were applied to actual statistics from the 1961 – 1990 to generate 105 years of data for each climate scenario. The SWAT model was used to simulate watershed processes for each scenario. The streamflow output was analyzed with the Indicators of Hydrologic Alteration program, which calculated multiple hydrologic indices that were then compared back to a baseline scenario. This analysis showed that large changes in projected annual precipitation caused significant hydrologic alteration. Similar alterations were obtained using scenarios with minimal annual precipitation change. This was accomplished with seasonal shifts in precipitation, or by significantly increasing annual temperature. One scenario showing an increase in spring precipitation accompanied by a decrease in summer precipitation caused an increase in both flood and drought events for the study area. The results of this study show that climate change has the potential to alter hydrologic regimes in Northeast Kansas.
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Intensifying Agricultural Water Management in the Tropics : A cause of water shortage or a source of resilience?Dile, Yihun January 2014 (has links)
Frequent climatic shocks have presented challenges for rainfed agriculture in sub-Saharan Africa. Appropriate water management practices are among the solutions to the challenges. The role of water harvesting in achieving sustainable agricultural intensification and specified resilience was explored. Suitable areas for water harvesting in the Upper Blue Nile basin were identified. The usefulness of the Curve Number method for surface runoff estimation was evaluated, and was found to perform satisfactorily. The impact of climate change in the Lake Tana sub-basin was studied. A decision support system was developed for locating and sizing of water harvesting ponds in the SWAT model. Methodological developments enabled analysis of the implications of water harvesting intensification in a meso-scale watershed in the Lake Tana sub-basin. Results suggest that water harvesting can increase agricultural productivity, sustain ecosystems and build specified resilience, and thereby contribute to sustainable agricultural intensification. There is considerable potential for water harvesting in the Upper Blue Nile Basin. Rainfall may increase in the Lake Tana sub-basin due to climate change. Supplementary irrigation from water harvesting ponds and better nutrient application increased staple crop production by up to three-fold. Moreover, a substantial amount of cash crop was produced using dry seasonal irrigation. Water harvesting altered the streamflow regime, and reduced sediment loss from the watershed. Water harvesting can play an important role in food security. It showed potential to buffer climatic variability. In the watershed studied, water harvesting will not compromise the environmental water requirements. Instead, increased low flows, and reduced flooding and sediment loss may benefit the social-ecological systems. The adverse effects of disturbance of the natural flow variability and sediment influx to certain riverine ecosystems warrant detailed investigation. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Manuscript. Paper 5: Epub ahead of print. Paper 6: Manuscript.</p> / Water resources management and social-ecological resilience
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Modelování znečištění povrchových vod v CHKO Křivoklátsko s využitím GIS / Modelling of surface water pollution in Krivoklatsko protected area using GISŠereš, Michal January 2014 (has links)
Environmental modelling is lately becoming to be one of the most important decision support systems. Hydrological models present significant potential for use especially in area of surface and groundwater protection. In the diploma thesis, the Soil and Water Assessment Tool (SWAT) was used to evaluate nitrate surface water pollution in nine catchments situated in Křivoklátsko protected area during the period of 2003 - 2010. Modelling process consist of assorted consequent steps. First the hydrological model of each catchment was created. Afterwards the sensitivity analysis was conducted to select most sensitive model parameters. Calibration process was carried out after the parameters selection using SWAT-CUP automatic calibration tool. Model results were visualized and evaluated. The results of the model suggested, that the area of interest was not widely endangered by nitrate pollution. Within each catchment the critical source areas of nitrate pollution were identified. It was observed that these areas are related with intensive agricultural areas. Nitrate leaching ranged from 6 kg.ha-1 to 10 kg.ha-1 per year in agriculture areas. Some areas exceed this amount. Nitrate loss from most of the area of interest ranged from 0 kg.ha-1 to 4 kg.ha-1 per year. Concentrations of nitrates in modeled...
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Avaliação do modelo Soil and Water Assessment tool (SWAT) na bacia hidrográfica do Ribeirão TaquaruçuNoda, Fernanda Sousa dos Santos 18 April 2018 (has links)
Devido ao processo de crescimento das cidades e atividade agrícolas há impactos que afetam
os recursos hídricos como a escassez, degradação da qualidade de água e consequente
conflitos de usos. Neste contexto, os modelos hidrológicos são importantes ferramentas para
avaliar o comportamento hídrico de bacias hidrográficas, além de também poderem ser
utilizados na previsão de cenários a fim de verificar o impacto do uso e ocupação do solo.
Assim, o presente estudo teve como finalidade avaliar o desempenho do modelo Soil and
Water Assessment Tool (SWAT) na simulação da vazão na Bacia Hidrográfica do Ribeirão
Taquaruçu. A calibração automática foi realizada com o programa SWAT-CUP, em passo
diário, com dados de duas estações fluviométricas da BRK Ambiental no período de abril de
2013 a julho de 2014, enquanto os dados de agosto de 2014 a agosto de 2015 foram utilizados
no período de validação. A análise de sensibilidade foi realizada com 14 parâmetros
selecionados entre aqueles mais significativos para a simulação de vazão em região do bioma
Cerrado. Os resultados da análise de sensibilidade indicaram que os parâmetros mais
influentes são o SOL_K (condutividade hidráulica saturada do solo) e CN2 (curva número
para a condição II). Para avaliação do desempenho do modelo foram utilizadas as funções
objetivos Nash-Sutcliffe (NSE) e o coeficiente de determinação (R2) que indicaram, no
período de calibração, os seguintes valores: -0,05 e 0,55 (sub-bacia 1); 0,51 (sub-bacia 3),
respectivamente. Já no período de validação foram apresentados os seguintes resultados para
NSE e R2: 0,44 e 0,54 (sub-bacia 1); 0,24 e 0,29 (sub-bacia 3), nesta ordem. Considerando
que o objeto de estudo é importante por ser responsável por grande parte do abastecimento de
água do município de Palmas – TO e que o software não conseguiu simular de forma
adequada as vazões mínimas, os resultados são considerados insatisfatórios. / Due to the process of city growth and agricultural activity there are impacts that affect water
resources such as scarcity, degradation of water quality and consequent conflicts of uses. In
this context, hydrological models are important tools to evaluate the hydrological behavior of
watersheds, and can also be used to predict scenarios to verify the impact of land use and
occupation. Thus, the present study had as purpose to evaluate the performance of the Soil
and Water Assessment Tool (SWAT) model in the flow simulation in the Ribeirão Taquaruçu
Watershed. The automatic calibration was performed with the SWAT-CUP program, in a daily
step, with data from two BRK Ambiental fluviometric stations from April 2013 to July 2014,
while data from August 2014 to August 2015 were used in the period of validation. The
sensitivity analysis was performed with 14 parameters chosen considering the most
significant ones for the simulation of flow in the Cerrado region. The results of the sensitivity
analysis indicated that the most influential parameters are the SOL_K (saturated hydraulic
conductivity of the soil) and CN2 (number curve for condition II). The Nash-Sutcliffe
objective functions (NSE) and the determination coefficient (R2) were used to evaluate the
performance of the model, which indicated, in the calibration period, the following values: -
0.05 and 0.55 (sub-basin 1); 0.51 (sub-basin 3), respectively. In the validation period, the
following results were presented for NSE and R2: 0,44 and 0,54 (sub-basin 1); 0.24 and 0.29
(sub-basin 3), in that order. Considering that the object of study is important because it is
responsible for a large part of the water supply of the municipality of Palmas – TO and that
the software was not able to simulate the minimum flows adequately, the results are
considered unsatisfactory.
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EVALUATION OF VEGETATED FILTER STRIP IMPLEMENTATIONS IN DEEP RIVER PORTAGE-BURNS WATERWAY WATERSHED USING SWAT MODELLinji Wang (5930996) 16 January 2019 (has links)
In 2011, the Deep River Portage-Burns Waterway Watershed was identified as a priority in the
Northwest Indiana watershed management framework by the Northwester Indiana Regional
Planning Committee. 319 grant cost-share programs were initiated in effort of maintaining and
restoring the health of Deep River Portage-Burns Waterway Watershed. A watershed management
plans have been developed for this watershed which proposed the implementation of vegetated
filter strips (VFS) as an option. In this thesis work, the effectiveness of VFS as a best management
practice (BMP) for the Deep River system was evaluated using a hydrological model scheme. <div><br></div><div>In this research, a Nonpoint Source Pollution and Erosion Comparison Tool (NSPECT) model and
a Soil Water Assessment Tool (SWAT) model were constructed with required watershed
characteristic data and climate data. The initial hydrologic and nutrient parameters of the SWAT
model were further calibrated using SWAT Calibration and Uncertainty Programs (SWAT_CUP)
with historical flow and nutrient data in a two-stage calibration process. The calibrated parameters
were validated to accurately simulate the field condition and preserved in SWAT model for
effectiveness analysis of BMP implementations. </div><div><br></div><div>To evaluate the effectiveness of VFS as a BMP, four different scenarios of VFS implementations
along the Turkey Creek was simulated with the calibrated SWAT model. With the implementation
of VFS in the tributary subbasin of Turkey Creek, the annual total phosphorus (TP) of the VFS
implemented subbasin was reduced by 1.60% to 78.95% and the annual TP of downstream
subbasins were reduced by 0.09% to 55.42%. Daily percentage of TP reductions ranged from 0%
to 90.3% on the VFS implemented subbasin. Annual TP reductions of the four scenarios ranged
from 28.11 kg to 465.01 kg.<br></div>
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Optimizing Feedstock Logistics and Assessment of Hydrologic Impacts for Sustainable Bio-Energy ProductionHa, Mi-Ae 1979- 14 March 2013 (has links)
Rising world petroleum prices and global warming are contributing to interest in renewable energy sources, including energy produced from agricultural crops and waste sources of biomass. A network of small mobile pyrolysis units may be the most cost effective system to convert biomass from agricultural feedstocks to bio-crude oil. Mobile pyrolysis units could be moved to the feedstock production fields thereby greatly simplifying feedstock logistics. In the North Central (NC) region of the U.S., possible feedstocks are corn stover, energy sorghum, and switchgrass. A grid-based Geographic Information System (GIS) program was developed to identify optimum locations for mobile pyrolysis units based on feedstock availability in the NC region. Model builder was used to automate the GIS analysis. Network analysis was used to find the best route to move the mobile pyrolysis units to new locations and to identify the closest refinery to transport the bio-crude oil.
To produce bioenergy from feedstocks, the removal of biomass from agricultural fields will impact the hydrology and sediment transport in rural watersheds. Therefore, the hydrologic effects of removing corn stover from corn production fields in Illinois (IL) were evaluated using the Soil Water Assessment Tool (SWAT). The SWAT model was calibrated and validated for streamflow and sediment yields in the Spoon River basin in IL using observed data from the USGS. The modeling results indicated that as residue removal rates increased, evapotranspiration (ET) and sediment yields increased, while streamflows decreased.
Biochar is a carbon-based byproduct of pyrolysis. To ensure that the mobile pyrolysis system is economically and environmental sustainable, the biochar must be land applied to the feedstock production fields as a soil amendment. An assessment of hydrologic changes due to the land application of biochar was made using the SWAT model in the Spoon River basin and changes in soil properties due to incorporation of biochar into the soil obtained from laboratory experiments by Cook et al. (2012). Model simulations indicated that a biochar application rate of 128 Mg/ha decreased water yield, and sediment yield in surface runoff and increased soil moisture and ET.
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Modelling Hydrological and Hydrodynamic Processes in Lake Tana Basin, EthiopiaSetegn, Shimelis Gebriye January 2010 (has links)
Lake Tana Basin is of significant importance to Ethiopia concerning water resources aspects and the ecological balance of the area. The growing high demands in utilizing the high potentials of water resource of the Lake to its maximal limit, pictures a disturbing future for the Lake. The objective of this study was to assess the influence of topography, soil, land use and climatic varia-bility on the hydrological and hydrodynamic processes of the Lake Tana Basin. The physically based SWAT model was successfully calibrated and validated for flow and sediment yield. Se-quential uncertainty fitting (SUFI-2), parameter solution (ParaSol) and generalized likelihood un-certainty estimation (GLUE) calibration and uncertainty analysis methods were compared and used for the set-up of the SWAT model. There is a good agreement between the measured and simulated flows and sediment yields. SWAT and GIS based decision support system that uses multi-criteria evaluation (MCE) was used to identify the most vulnerable areas to soil erosion in the basin. The results indicated that 12 to 30.5% of the watershed is high erosion potential. Pro-jected changes in precipitation and temperature in the basin for two seasons were analyzed using outputs from fifteen global climate models (GCMs). A historical-modification procedure was used to downscale large scale outputs from GCM models to watershed-scale climate data. The results showed significant changes in streamflow and other hydrological parameters in the period between 2045-2100. SWAT was combined with a three dimensional hydrodynamic model, GEMSS to investigate the flow structure, stratification, the flushing time, lake water balance and finally the Lake‘s water level response to planned water removal. We have found an alarming and dramatic fall of the water levels in Lake Tana as response to the planned water withdrawal. The combination of the two models can be used as a decision support tools to better understand and manage land and water resources in watersheds and waterbodies. The study showed that the Lake Tana Basin may experience a negative change in water balance in the forthcoming decades due to climate change as well as over abstraction of water resources. / QC 20100720
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Os efeitos da cultura nas relações entre estilo de liderança, confiança e comprometimento: comparando equipes de operações especiais no Brasil e Estados UnidosMotta, Roberto Bezerra 30 November 2015 (has links)
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Previous issue date: 2015-11-30 / Esse trabalho tem como objetivo compreender a influência da cultura no estilo de liderança em equipes de operações especiais, usando como referência teórica principal as pesquisas de Geert Hofstede sobre dimensões culturais. Buscamos entender como os elementos da cultura nacional e da cultura organizacional influenciam o estilo de liderança comparando equipes de operações especiais do Brasil e dos Estados Unidos. As unidades brasileiras estudadas foram o Batalhão de Operações Especiais (BOPE) da Polícia Militar do Rio de Janeiro e a Coordenadoria de Recursos Especiais (CORE) da Polícia Civil do Rio de Janeiro. A equipe de operações especiais estudada nos Estados Unidos foi a SWAT. Os resultados apontam para a influência da cultura organizacional, e não da cultura nacional, no estilo de liderança.
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