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The proficient supply of water and nutrients is a key factor for successful vegetable production under greenhouses. This field experiment was conducted during 2018–2019 under a completely randomized design to evaluate the effects of drip irrigation and nutrient schedule on soil water dynamics and the productivity of greenhouse tomato. The experiment consisted of two irrigation schedules, i.e., I1 (irrigation applied from week 1 to 2 on the basis of 100% pan evaporation (Epan), week 3 to 8 on the basis of 40% of Epan, week 9 to 14 on the basis of 60% of Epan, week 15 to 20 on the basis of 80% of Epan, week 21 to 24 on the basis of 100% of Epan) and I2 (irrigation applied on the basis of 100% of Epan throughout the crop period) with a five-nutrient schedule, viz., F1 (100% NPK applied through the conventional method), F2 (100% N applied through fertigation + PK through the conventional method), F3 (100% NK applied through fertigation + P through the conventional method), F4 (100% NPK applied through fertigation) and F5 (50% NPK applied through the conventional method + 150% NPK applied through fertigation). The soil moisture content (SMC) and its depletion were measured during growing season. The tomato yield was significantly higher under I2. However, water use efficiency (WUE) was significantly higher under I1 treatment. Among the nutrient schedules, the yield and WUE were significantly higher in F5 treatment. The net returns were highest under F5 and lowest under F1. The Benefit:Cost ratio was highest in F4 and lowest under F1. The irrigation level I2 (irrigation applied on the basis of 100% of Epan throughout the crop period) with fertigation treatment F4 (100% NPK applied through fertigation) was the best strategy for obtaining the maximum productivity of tomato under the greenhouse. It can be concluded that the drip-based fertigation enhances the crop yield and net returns and therefore may be promoted to increase the income of the farmers.

The present study examined 35 morphometric parameters related to stream/drainage network, catchment geometry, and relief aspects for hydrological characterization of the Thana Dam catchment using geospatial tools and techniques. The dam catchment was delineated using the high-resolution Advanced Land Observing Satellite Phased Array type L-band Synthetic Aperture Radar (ALOS PALSAR) Digital Elevation Model (DEM) data in ArcGIS 10.4.1 software using the Arc Hydro tools. The catchment is comprised of 4th order stream, obtained using a stream threshold value of 100 m length. The lower values of elongation ratio (0.61), circularity ratio (0.22), and form factor (0.29) indicated higher soil erosion potential, mainly due to their inverse relationship with land erodibility. Moreover, the higher values of stream frequency (15.7), drainage density (>5.0), drainage texture (7.48 km-1), and mean bifurcation ratio (4.08-6.33) indicated higher runoff potential, which would intensify the soil erosion, mainly due to their direct relationship with erodibility. Bifurcation ratio, elongation ratio, circulatory ratio, form factor, altogether indicated an elongated shape of the catchment with a fine drainage texture. The higher values of bifurcation ratio and texture ratio of the catchment also indicated severe overland flow (low infiltration rate) with a limited scope for groundwater recharge in the area, which in turn might significantly encourage the soil erosion. Overall, it was concluded that the catchment has a huge runoff potential resulting in high soil erosion due to its fine texture, impermeable subsurface material, steep slope, low infiltration rate, limited vegetation, longer duration of overland flow, and higher surface runoff. The morphometric analysis was found to be suitable for identifying catchment shape and the factors affecting hydrologic conditions and erodibility of the catchment. Thus, Geo-informatics based morphometric analysis of a reservoir catchment can be useful to study the erosion potential in relation to hydrologic (rainfall-runoff relationship) and other related land characteristics (e.g., relief, slope, infiltration rate, etc.).

The WEPP watershed model was applied for simulation of storm-wise runoff and sediment yield from two forest watersheds (WS-I and WS-II) having an area of 1.85 and 21.3 ha, respectively, situated in Shivalik foot-hills of North-West, India. The WS-I was divided into 29 hillslopes and 18 channels, while WS-II was divided into 35 hillslopes and 25 channels. CLIGEN software was used to create the climate file, which was based on the observed meteorological data. The soil, slope, and land-use management files were created for each hillslope and channel. The model was calibrated on WS-I and then applied to WS-II to ascertain whether the model must be calibrated every time it is applied to a new watershed in the region. The WEPP model was calibrated and validated by using the hydrological data of 22 storms (1982–2004) for WS-I and 13 storms (2001–4) for WS-II. The statistics showed that calibrated model for WS-I, simulated storm-wise runoff, and sediment yield for WS-II with advisable precision as substantiated by the lower values of RMSE (5.43 mm and 0.31 Mg/ha) and average error (2.09 mm and 0.09 Mg/ha) and high values of correlation coefficient (0.93 and 0.86) and model efficiency (83.90% and 69.50%). It is evident from this study that once the WEPP model has been calibrated on a representative watershed, it can be effectively applied to uncalibrated/ungauged watersheds in Shivalik foot-hills for watersheds with similar characteristics.