Abstract: Measuring discharge in a developing and riverine country like Bangladesh is very important to predict flood and proper land utilization for sustainable development. The Teesta River is one of the most important trans-boundary rivers of northern region of Bangladesh. Bangladesh has long argued that India’s construction of the Gazoldoba Barrage upstream of Dalia has significantly reduced the availability of water in the dry season. Furthermore, the release of water during the monsoon season causes flooding and bank erosion in downstream. With this issue in mind, a hydrological model for the Teesta basin has been developed using a semi distributed model Soil and Water Assessment Tool (SWAT). In this research, we are interested to investigate discharge estimation and to determine watershed parameters, land use, soil and slope modeled of Teesta watershed and the percentage area distribution, which are outlined from the data observed for Northern region of Bangladesh by using SWAT. For model calibration SWAT_CUP SUFI-2 algorithm has been used at Kaunia station, out let of Teesta watershed. The calibration and validation periods have been selected 2009 to 2013 and 2014 to 2017 respectively. Discharge for both daily and monthly time step are generated by the model. The performance of the calibration and validation has been assessed by different statistical techniques. During the calibration, in daily simulation the NSE value is 0.80 while R2 is 0.82, which are quite reasonable and during the validation period the values of NSE and R2 are 0.76, 0.77 respectively also quite reasonable. In monthly simulation, the NSE, R2 values for calibration period are 0.92 and 0.93 respectively while the values of validation period are 0.84 and 0.88, respectively. Overall, the model efficiency is satisfactory. The performance of the model indicates that such an approach can indeed produce an acceptable result for both daily and monthly simulation. The results are presented graphically to compare observed and simulated result.

Abstract: Discharge estimation from rainfall event is a very difficult task due to various influencing factors. Various physiographic parameters play a vital role for surface and channel flow. Actual field values of several hydrological event parameters are sometimes impossible to ascertain in developing country like Bangladesh. Hydrological model can be used to measure the discharge and physiographic parameter. Discharge for Khowai river basin, one of the important basin in Bangladesh is simulated for period 1995-2016 using a semi-distributed model Soil and water Assessment Tool (SWAT). Model calibration and validation have been performed for daily time periods using Sequential Uncertainty Fitting version 2(SUFI-2) algorithm within SWAT-CUP (SWAT Calibration Uncertainty program) using 22 physiographic parameters.  Our calibration outputs for the period 2000-2008 showed good correlation between observed and model simulated values with NSE=0.81 and R2=0.86.  During Validation period from 2009-2016 the NSE and R2 were 0.69 and 0.78 respectively which are reasonable. Sensitivity analysis is an integral part of model development and involves analytical examination of input parameters to aid in model validation and provide guidance for future research.  Sensitivities of 22 input parameters have been analyzed using SUFI-2 algorithm in SWAT-CUP. It is done by global and one-at-a-time sensitivity procedures.  For Khowai river four parameters show most sensitive for both of global and one-at-a-time sensitivity procedures.  They are SCS surface runoff curve (CN2.mgt), baseflow alpha factor for bank storage (ALPHA_BNK.rte), ground water delay time (GW_DELAY.gw), Soil evaporation and compensation factor (ESCO.hru ). From the study that focusing on sensitive parameters can lead to a better understanding and to better estimated values and thus reduced uncertainty of model and it helped to simulate reliable local hydrology of watershed of Bangladesh.

Abstract: The study area, Sariska Sanctuary established in the year 1955-56 is situated in Alwar district between parallels of 27⁰ 14’5” and 27⁰ 52’12” N latitude and 76⁰ 14’20” and 76⁰ 32’12” E longitudes and roughly shaped like jumping frog, covering an area of 866.13 sq. Kms. with core area of 492 sq. kms. (Fig.1.1) Situated amidst the high ranges of Aravallies, undulating plateau and wide valley, the Sariska Sanctuary occupies a pride place in Rajasthan for conservation of wildlife for more than a century. The Sariska Sanctuary is one of the 28 Tiger Project of India. Consist 4 forest ranges, Sariska (205 Sq.kms). Tehla (341 Sq.kms.).

Abstract: Groundwater depletion has emerged as a significant environmental and socio-economic challenge in Rajasthan, where limited rainfall and high agricultural dependency put immense pressure on water resources. This study aims to assess groundwater depletion rates and evaluate the recharge potential across different regions of Rajasthan. By integrating historical groundwater level data, satellite imagery, and hydrological modeling, we analyzed trends in groundwater depletion and identified factors driving these changes, including land use practices, population growth, and climate variability. Recharge potential was evaluated using a combination of water balance techniques and remote sensing, allowing for a spatially resolved understanding of recharge capabilities.