Assessing strategic water availability using remote sensing,GIS and a spatial water budget model: case study of the Upper Ing Basin,Thailand     

Krishna Bahadur KC 《水文科学杂志》2013,58(6):994-1014

Abstract

This paper assesses strategic water availability and use under different development pathways on a basin scale using remote sensing (RS), geographical information systems (GIS) and a spatial water budget model (SWBM). The SWBM was applied to the Upper Ing Basin in northern Thailand to investigate the spatial and temporal variations in the location of streams and water yields from different parts of the basin. The base simulation was carried out for the years 1998–2007 using a DEM and actual land-use data at 100-m resolution. The simulated stream network was compared with topographic maps under different flow conditions, which were successfully represented. The 10-year average simulated river flow rate was 1300 L/s, but it more than doubled during periods of heavy rainfall and decreased below 600 L/s in dry seasons. The total length of the streams (based on flow threshold of 25 L/s) on a typical day in the dry season differed by a factor of approx. 1.5. Agricultural water needs and possible extraction were assessed and presented by dividing the basin into 10 different zones based on the stream network. The results show that there is the potential for harvesting significant quantities of water at different spatial gradients with no initial water supply for irrigation. Monthly water yields for each zone were computed; the results varied from less than 50% to over 137% of the per hectare water yield for the entire basin. This variation was due to differences in topography and land cover. The impact of land use and climate change on streamwater availability was also studied. The basin shows very different hydrological responses. The changes in average river flow relative to the base simulation were +27.6%,??32.1%, +94% and +52.9% under deforestation, changing land use from paddy field to orchard, bare soil and increased rainfall scenarios, respectively.

Citation Bahadur KC, K. (2011) Assessing strategic water availability using remote sensing, GIS and a spatial water budget model: case study of the Upper Ing Basin, Thailand. Hydrol. Sci. J. 56(6), 994–1014.  相似文献   

Seabirds and chronic oil pollution: self-cleaning properties of gulls, Laridae, as revealed from colour-ring sightings     

Camphuysen KC 《Marine pollution bulletin》2011,62(3):514-519

Mystery oil spills off the Dutch coast affected colonial, adult Lesser Black-backed Gulls prior to and within the breeding season. From colour-ringed individuals, it was demonstrated that most oiled birds survived and were clean within a few weeks and often bred successfully. Further evidence of self-cleaning properties of Larus-gulls is provided from a long-term colour-ringing project (1984-2009). In total 46 birds were reported ‘oiled’, two died, but the majority cleaned itself and survived for up to 20 years after being oiled. From colour-ring data and 30 years of beached bird surveys (1980-2010) it is demonstrated that the effects of chronic oil pollution is larger in winter than in summer; a reflection of seasonal differences in exposure and environmental conditions. The self-cleaning properties of gulls are such that long-term survival is not necessarily jeopardised and even in a breeding season, not all is lost in case of a spill.  相似文献   

Estimating time parameters of overland flow on impervious surfaces by the particle tracking method     

Manoj KC 《水文科学杂志》2013,58(2):294-310

Abstract

Travel time and time of concentration T_c are important time parameters in hydrological designs. Although T_c is the time for the runoff to travel to the outlet from the most remote part of the catchment, most researchers have used an indirect method such as hydrograph analysis to estimate T_c. A quasi two-dimensional diffusion wave model with particle tracking for overland flow was developed to determine the travel time, and validated for runoff discharges, velocities, and depths. Travel times for 85%, 95% and 100% of particles arrival at the outlet of impervious surfaces (i.e. T_t85, T_t95, and T_t100) were determined for 530 model runs. The correlations between these travel times and T_c estimated from hydrograph analysis showed a significant agreement between T_c and T_t85. All the travel times showed nonlinear relationships with the input variables (plot length, slope, roughness coefficient, and effective rainfall intensity) but showed linear relationships with each other.