The spatiotemporal variation of surface soil moisture is a key subject variable need to be assessed accurately since it plays a crucial role in partitioning of rainfall into runoff and infiltration. Active microwave remote sensing has offered prominent potential towards accurate estimation of surface soil moisture. Present study utilizes ERS-2 SAR image for estimating surface soil moisture by incorporating the effect of topography, vegetation and surface roughness over three land cover types namely; sugarcane, wheat and barren land through Multiple Linear Regression (MLR) approach. Five independent variables considered for MLR analysis include backscatter coefficient (\(σ^0\) ), local incidence angle (\(α_i\)), surface roughness height (\(h_s\)), Leaf Area Index (LAI) and Plant Water Content (PWC), respectively. Results indicate retrieval of soil moisture within ± 20% accuracy for all the three land cover types with higher accuracy for barren land (i.e. R2 ~ 0.78 and RMSE = 1.31) as compared to the other two land cover types (i.e. sugarcane; R2 ~ 0.67 and RMSE = 3.60 and wheat; R2 ~ 0.72 and RMSE = 1.94). The present study reveals the effectiveness of MLR approach in the retrieval of surface soil moisture using fewer numbers of variables.
Landsat TM and ETM+ datasets are useful for forest change detection (FCD) at good accuracy level. Classified forest maps have been prepared using NDVI calculated from Landsat-5 TM (2009) and Landsat-7 ETM+ (2002) datasets for FCD using post-classification technique. About 58.59% of reviewed area shows positive changes, 33.69% no-changes and 7.72% negative changes with 77.84% accuracy. This accuracy insists limitations of present FCD analysis. Therefore, improved post-classification technique was formulated for precise FCD using field data and statistical techniques. Information about stable land surface (water bodies, rocky lands, deep forests, etc.) was used for normalisation of exaggerated reflectance in vegetation indices i.e. greenness. About 70.08% land estimated using second approach shows stable vegetation, 23.59% positive changes and 6.33% negative changes. Higher accuracy (95.21%) itself shows improvement in FCD technique and efficient applicability for sustainable land management.
The geomorphic effectiveness of floods is evaluated in terms of unit stream power (\(\omega\)) and boundary shear stress (\(\tau\)) for floods on the Par River. The highest values for \(\omega\) and \(\tau\) for a flood on the river are 52125 W/m2 and 3320 N/m2, respectively. The estimated Froude numbers are <1 indicating subcritical flows. It is >1 for a few constricted reaches showing supercritical or shooting flows. High values of Reynolds number reveal that the flood discharges were extremely turbulent. Values of critical velocity for the inception of cavitation (Vc) show that none of the powerful floods on the river, except two, exceed the conditions. Estimates of \(\omega\), \(\tau\) and velocity associated with transported boulders indicate that all floods were competent to move large boulders of more than 5.5 m in diameter. The efficiency of high-magnitude flood events is evident from the presence of a variety of geomorphic features.
The study presents an approach to map Land Use / Land Cover Change (LULCC) at large scale and processing techniques that permit higher accuracy. IRS RESOURCESAT-2 LISS-IV images of Nellore district of Andhra Pradesh were used to apply the classification technique. In multi-scale feature extraction approach LULCC takes two forms i.e. conversion from one category of LULCC to another and modification of condition within a category. Thus, major LULCC classes were extracted using object based approach and uncertain classes were identified using onscreen knowledge based method. The results showed in 2009, the accuracy of cropland, water body and built-up segments were 99.3%, 94.79% and 89.72%, respectively, whereas, in 2013 the accuracies were 94.31%, 88.26% and 81.20%, respectively. Hence, this classification approach can be useful in different landscape structure over the time, which can be quantified and assessed to achieve a better understanding of the land cover.
Unlike many other mainstream disciplines that only seek to broaden knowledge and add to it, and thus become additive, women’s studies tries to question and posit new ways of thinking, inaugurating paradigm shifts and thus becoming subversive by trying to question established hierarchies of knowledge. This has not been an easy journey and the practioners of this new approach have faced numerous odds as all pioneering endeavours encounter. This is a story that needs to be told and the present book attempts to do this by charting the trajectories of eighteen women’s studies scholars and their academic sojourn. These scholars have been confined not just to the traditional dominant hierarchies of knowledge but by their own making, ventured into new areas, which has now emerged from the margins to the forefront and struggled to give women’s studies a visibility.