A multi-objective calibration approach using in-situ soil moisture data for improved hydrological simulation of the Prairies     

Sujata Budhathoki  Prabin Rokaya  Karl-Erich Lindenschmidt  Bruce Davison 《水文科学杂志》2020,65(4):638-649

ABSTRACT

Traditionally, hydrological models are only calibrated to reproduce streamflow regime without considering other hydrological state variables, such as soil moisture and evapotranspiration. Limited studies have been performed on constraining the model parameters, despite the fact that the presence of a large number of parameters may provide large degree of freedom, resulting in equifinality and poor model performance. In this study, a multi-objective optimization approach is adopted, and both streamflow and soil moisture data are calibrated simultaneously for an experimental study basin in the Saskatchewan Prairies in western Canada. The results of this study show that the multi-objective calibration improves model fidelity compared to the single objective calibration. Moreover, the study demonstrates that single objective calibration performed against only streamflow can fairly mimic the streamflow hydrograph but does not yield realistic estimation of other fluxes such as evapotranspiration and soil moisture (especially in deeper soil layers).  相似文献   

Impacts of future climate on the hydrology of a northern headwaters basin and its implications for a downstream deltaic ecosystem     

Prabin Rokaya  Daniel L. Peters  Mohamed Elshamy  Sujata Budhathoki  Karl-Erich Lindenschmidt 《水文研究》2020,34(7):1630-1646

Anthropogenic and climatic-induced changes to flow regimes pose significant risks to river systems. Northern rivers and their deltas are particularly vulnerable due to the disproportionate warming of the Northern Hemisphere compared with the Southern Hemisphere. Of special interest is the Peace–Athabasca Delta (PAD) in western Canada, a productive deltaic lake and wetland ecosystem, which has been recognized as a Ramsar site. Both climate- and regulation-induced changes to the hydrological regime of the Peace River have raised concerns over the delta's ecological health. With the damming of the headwaters, the role of downstream unregulated tributaries has become more important in maintaining, to a certain degree, a natural flow regime, particularly during open-water conditions. However, their flow contributions to the mainstem river under future climatic conditions remain largely uncertain. In this study, we first evaluated the ability of a land-surface hydrological model to simulate hydro-ecological relevant indicators, highlighting the model's strengths and weaknesses. Then, we investigated the streamflow conditions in the Smoky River, the largest unregulated tributary of the Peace River, in the 2071–2100 versus the 1981–2010 periods. Our modelling results revealed significant changes in the hydrological regime of the Smoky River, such as increased discharge in winter (+190%) and spring (+130%) but reduced summer flows (−33%) in the 2071–2100 period compared with the baseline period, which will have implications for the sustainability of the downstream PAD. In particular, the projected reductions in 30-day and 90-day maximum flows in the Smoky River will affect open-water flooding, which is important in maintaining lake levels and connectivity to perimeter delta wetlands in the Peace sector of the PAD. The evaluation of breakup and freeze-up flows for the 2071–2100 period showed mixed implications for the ice-jam flooding, which is essential for recharging high-elevation deltaic basins. Thus, despite projected increase in annual and spring runoff in the 2071–2100 period from the Smoky sub-basin, the sustainability of the PAD still remains uncertain.  相似文献   

An appraisal of water resources of India and need for national water policy     

S. L. Kayastha Dr. 《GeoJournal》1981,5(6):563-572

Water is one of the basic resources of mankind and is vital to all forms of life. Although water is abundant covering 3/4 of the earth, yet it is a scarce resource; its universal use and the fact that only 3% is drinkable, makes its utilization and conservation, a most complicated problem, which has received inadequate attention. Water is like Shiva; it can create, preserve and destory. It is man's greatest friend and for; while it sustains life, it is a killer also. Water resources are limited but the demand for water continues to rise steeply, making the need most urgent for an efficient planning and implementation of programme of water resource appraisal, development, conservation and management.  相似文献