15 / 2023-12-16 05:13:45

An Approach to Method for Water Yield Spatiotemporal Prediction in Basins without Records. Case: Two Micro Basins of Paito River Basin, Venezuela

method,water yield,spatio-temporal prediction

.In this study, an approach to method for water yield spatiotemporal prediction was applied in two micro-basins that are drained by Cantilote’s creek and Quintana`s creek. These two creeks pour their waters to Paito River basin, Venezuela. Both of these creeks have no hydrometeorological measurement records. Geomorphological characteristics of micro-basins were obtained using digital elevation models acquired from ALOS PALSAR satellite. Two models were included for spatiotemporal prediction of hydrometeorological variables. First model involved deterministic and stochastic components, calibrated using two time series (TS). TS-1 consisted of records from 227 precipitation stations and 62 evaporation stations collected by Environment Ministry during 1980-1999. TS-2 included records from 28 precipitation stations and 18 evapotranspiration stations collected by the National Institute of Meteorology and Hydrology during 2015-2018. Second model estimated effective precipitation from TS-2 precipitation maps, runoff coefficient from land use and land cover (LULC) prediction. LULC were estimated on 59 Landsat 8OLI images for 2015-2018. A comparison of the monthly spatially distributed precipitation was estimated by the Ordinary Kriging (OK) method using ArcGIS 10.0. Precipitation was estimated from applying OK on the Ministry of Environment stations for the Quintana and Cantilote creels’s micro-basins during 1980-1999. These results were compared with the monthly precipitation observed in a meteorological station (MS) monitored by Central Hydrologic Company (HIDROCENTRO, in Spanish) placed at Pao-Cachinche water reservoir, for TS-1, finding that a high proportion of the observations were close to the estimates, existing a univariate linear relationship between the estimates and observations of the monthly precipitation through a gradient of 0.86, which was approximate to a 1:1 ratio, supported by a determination coefficient between observations and estimates of 0.95, which confirms a high to very high correlation. Validation was carried out with observations of HIDROCENTRO-MS, resulting in determination coefficients upper to 0.95. Monthly water production estimated through a monthly surface water balance was similar both in TS-1 for a difference (P-E) and in TS-2 for a difference (PE-ET). Reduction was due to the fact of considering losses due to infiltration, PE/P ratio varied between 0.50 and 0.85 for rainy season, resulting in a surface flow that varied between 100,000 and 120,000 m³/month for the Quintana creek micro-basin and 25,000 to 30,000 m³/month for Cantilote creek, both for an exceedance probability of 80%. When considering inclusion of groundwater flow component, which was up to 100 times less than surface flow, total contributed volume was defined by surface flow.