The spinel ferrites with the compositional formula Ni0.8Zn0.2Fe2−xDyxO4 (x = 0, 0.004, 0.008, 0.012, 0.016) have been prepared using the sol–gel method. The X‐ray diffraction measurements confirm the cubic spinel structure of the sample with a space group of Fd‐3m. Morphological analysis of scanning electron microscope images reveals that the particles are spherical in shape. Energy dispersive X‐ray spectroscopy (EDX) confirms the elemental composition. Thermogravimetric analysis (TGA)/differential scanning calorimetry (DSC) analysis of synthesized dysprosium (Dy) doped Ni–Zn ferrites are carried out from 25 to 700 °C. Fourier‐transform infrared (FTIR) spectroscopy studies reveal the stretching and bending vibrations of the various bonds presented in the compounds. The UV–vis absorption spectrum indicates the energy gap values which small decrease with the Dy concentration increase. Raman spectroscopy reveals the crystal distortion and phases of the samples. The room temperature magnetic measurements (M–H loops) are carried out to study the effect of Dy doping on magnetic properties.

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The Indo-Gangetic plains (IGP) encompass a large alluvial track consisting of multi-tier aquifer system. Due to stride developmental activities and intensification of agriculture with higher irrigation water requirement, shallow groundwater regime is getting depleted causing hydrological drought. Spatio-temporal variation of seasonal drought pattern and drought severity in the IGP region was analysed for the period of 2005-2009, using Standardized water level index (SWI) with topo to raster methods of interpolation in geographic information system (GIS). Analysis of hydrological drought indicated that 40-60 % area in the IGP was affected by mild hydrological drought, whereas 2-7 % of the area was affected by extreme hydrological drought because of excessive and indiscriminate groundwater pumping leading to decline in groundwater level. SWI categories were correlated with the irrigation activity for better irrigation planning. Irrigation planning for the IGP was suggested for different SWI drought categories.

The analysis of stream flow trends of hydro-climatic variables such as stream flow, rainfall, and temperature provides useful information for effective water resource planning, design, and management. Trends in observed stream flow at seven gauging stations in the Ramganga river basin of North India were examined from 1981 to 2012 using the Mann-Kendall and Sen's slope. Lag 1 autocorrelation analyses were used to investigate the relationships between trends in stream flow and rainfall. Annual, monsoonal, and winter seasonal stream flow (p0.05) decreased gradually from upstream to downstream of the river, as did crop seasonal and decadal moving averaged standardized anomalies of streamflow for the entire basin. The streamflow's declining trend was partly attributed to higher water withdrawal, higher air temperature, and higher population, and partly to a significantly declining post-monsoon rainfall trend, particularly upstream and downstream. The changing monsoon rainfall pattern and the growing population both contributed significantly to the development of this trend.  The significant decreasing trend in stream flow at the upstream gauging station (-0.39 m3/s/year) was attributed to the significant decreasing trend in catchment rainfall (-8.40 mm/year). This study shows a strong positive correlation between stream flow and catchment rainfall (r=0.60). The Ramganga River basin is showing signs of drying up, as evidenced by the declining stream flow, post-monsoon rainfall, especially in the downstream area, and concurrently rising temperature trends. The Ramganga River basin's sustainable water management planning will be aided and made possible by the study's findings and recommendations, which will help stakeholders design strategies for stream flow restoration. This study thus highlights the urgent need for comprehensive water management planning in this basin by implementing procedures at various spatial scales that may be able to halt the trend of drying by improving river water use efficiency in a variety of sectors.