Showing papers by "K. P. Sudheer published in 2022"

Reconceptualizing HRU Threshold Definition in the Soil and Water Assessment Tool

Abstract: The Soil and Water Assessment Tool (SWAT) model simulates a watershed by dividing it into subbasins which are further divided into hydrologic response units (HRUs). User‐defined area thresholds for land use, soil, and slope are often used when defining HRUs during model setup to improve computational efficiency by reducing the number of HRUs. This, however, results in loss of watershed biophysical information due to the reapportionment of HRUs that fail to exceed the threshold to other dominant HRUs. This study presents an improved HRU definition method that minimizes the loss of watershed biophysical information without considerably increasing the number of HRUs and lowering the user‐defined HRU thresholds. Comparison of land use and soil distribution showed that the new HRU model closely matched the no‐threshold full HRU model, unlike the default threshold SWAT model in which the landscape distribution characteristics were inadequately represented. Simulated hydrological and water quality variables, as well as model parameterization, were also better characterized when using the proposed HRU definition method when compared with the default SWAT model. The number of HRUs with the new method (934) was only slightly higher than the default threshold model (589) but considerably lower than the full HRU model (29,288). This new HRU definition method can help modelers perform computationally efficient modeling without compromising the accuracy of biophysical inputs to the model.

Improved accuracy of storm surge simulations by incorporating changing along‐track parameters

Abstract: The estimation of maximum storm surges along a coast is indispensable for emergency action planning, design, and adaptation of coastal infrastructure. The existing studies on the Bay of Bengal coast have used synthetic tracks with constant track parameters such as the maximum wind speed, radius of maximum wind, and central pressure to estimate the probable maximum storm surges. However, the analysis of the best tracks from the Joint Typhoon Warning Center during 1978–2019 shows that the track parameters vary from origin to landfall locations. The reported studies along the Bay of Bengal have failed to capture such variations and overestimated probable maximum storm surges due to constant track parameters. Therefore, this study proposes a methodology for estimating wind speed of various return periods and associated track parameters that vary along a synthetic track. The wind speed of different return periods is computed at each eye location using the probabilistic approach. Thus, the calculated wind speeds vary from origin to landfall locations, and such a pattern of wind speed variation is observed to be similar to the historical cyclones. The radius of maximum wind and central pressure is calculated using the regression equations derived from historical tracks. The accuracy of the proposed methodology is investigated by simulating the cyclones Thane and Vardah that occurred along the Tamil Nadu coast. The results suggest that the varying track parameters using the proposed methodology produce realistic surge values similar to parameters from best track data, and it overcomes the overestimation of surge heights. The proposed methodology is further utilized to analyse the maximum surge scenarios along the Tamil Nadu coast resulting from various track shifts and angles of attack. The proposed methodology is expected to improve the estimation of storm surges in other basins.

Integrated Simulation Modeling Approach for Investigating Pore Water Pressure Induced Landslides

Abstract: Soil pore water pressure analysis is crucial for understanding landslide initiation and prediction. However, field-scale transient pore water pressure measurements are complex. This study investigates the integrated application of simulation models (HYDRUS-2D/3D and GeoStudio–Slope/W) to analyze pore water pressure-induced landslides. The proposed methodology is illustrated and validated using a case study (landslide in India, 2018). Model simulated pore water pressure was correlated with the stability of hillslope, and simulation results were found to be co-aligned with the actual landslide that occurred in 2018. Simulations were carried out for natural and modified hill slope geometry in the study area. The volume of water in the hill slope, temporal and spatial evolution of pore water pressure, and factor of safety were analysed. Results indicated higher stability in natural hillslope (factor of safety of 1.243) compared to modified hill slope (factor of safety of 0.946) despite a higher pore water pressure in the natural hillslope. The study demonstrates the integrated applicability of the physics-based models in analyzing the stability of hill slopes under varying pore water pressure and hill slope geometry and its accuracy in predicting future landslides.

Reliability of Hydrology and Water Quality Simulations Using Global Scale Datasets

Abstract: Physics‐based, comprehensive, distributed hydrologic models, such as the Soil and Water Assessment Tool, are a prime choice of decision makers and watershed managers for analyzing the impact of different land management practices on watershed hydrology and water quality. However, the decisions framed through the application of such models are highly affected by the model input data accuracy. On a global scale, the majority of watersheds are data‐limited (DL), and model input data at required spatial and temporal resolutions are unavailable, incomplete, or low in quality. Thus, the hydrological simulations are significantly influenced by poor representation and characterization of the system, which affects the reliability of simulations in DL regions. This study quantifies the effects of global‐scale dataset usage in ecohydrological simulations. The global‐scale datasets are generally coarse in spatial resolution and significantly affect the hydrology and water quality simulations. The average annual flow simulations were 35.7% higher for DL scenarios as compared to the data‐intensive scenario. Researchers with limited data should take special care to ensure that their simulations allow them to take informed decisions so that effective and reliable management system is planned. Validation with locally available data for land use and management practices may help increase reliability.

Development of protein enriched cold extruded pasta products using hybrid dried processed mushroom powder and defatted flours: A study on nutraceutical, textural, colour and sensory attributes

Abstract: Standardisation of the formulation for the development of three categories of protein enriched Ready -to -cook (RTC) pastas (defatted coconut-based pasta, soya-based pasta and mushroom-based pasta) was performed. Protein enrichment using defatted coconut flour (DFC-10, 15 and 20 g/100 g, microwave combined with fluidized bed dried mushroom powder (M-5, 10 and 15 g/100 g) and defatted soya flour (DFS-20, 25 and 30 g/100 g) were incorporated in the study. Highest swelling power of 2.5 g/g to 2.9 g/g was observed for mushroom-based pasta. Whereas maximum firmness of 57.22 N was observed in soya-based pasta sample with 30 g/100 g addition level. The optimal cooking time for coconut-based pasta was least - around 6 min with 20 g/100 g inclusion. However, the solid loss of DFC pasta samples gradually increased with the incorporation of DFC flour (6.8%–12.0%). Sensory evaluation using fuzzy logic model was performed for each category and the sample M1 with 5 g/100 g inclusion of mushroom powder was standardized as the best among the mushroom-based pasta. The standardized composition in defatted coconut-based pasta and defatted soya-based pasta category were DFC1 (10 g/100 g) and S 2 (25 g/100 g) respectively. The protein enrichment by partially replacing wheat with the by-products imparted high nutritive value and acceptance to the protein enriched pasta products. • Protein-enriched pasta was prepared by using defatted coconut flour, mushroom powder and defatted soy flour. • Combination of microwave and fluidized bed drying was used to produce mushroom powder with maximum nutrient retention. • The pasta quality was affected by the addition levels of the protein-rich supplements. • Fuzzy logic model was used to determine the pasta with best sensory properties within each supplement.

Effect of incorporation of various toppings in spent hen meat chips

Abstract: Spent hens are by-products of the egg industry and it has poor tenderness and less juiciness due to high cross-linking collagen content. Chips are popular snacks throughout the world due to their easy preparation and savoury flavour. Incorporation of spent hen meat in chips can provide a complete nutritious snack. The addition of toppings in spent hen meat snacks would give a unique taste and enhance the acceptance of consumers. The study was undertaken in the Department of Livestock Products Technology to analyse the effect of two different toppings namely, tandoori (T1) and chicken chip topping (T2) in spent hen chips for their physico-chemical, proximate, colour and sensory attributes. A higher pH value was found for control without toppings while water activity value was found significantly (p<0.001) higher for T1. Significant (p<0.001) difference was found for lightness (L*) between control and treatments. Redness (a*) and yellowness (b*) were found highest for T1. The highest sensory score for all sensory parameters was found for T2. Thus, chicken chips with 50 per cent spent hen meat dusted with five per cent chicken chip topping was highly accepted by the consumers due to its uniqueness in taste.

Susceptibility of Life Stages of Tribolium castaneum (Herbst) to Microwave Radiation

Abstract: Physical methods of stored grain pest management such as microwave radiation can be utilized as a preventive and curative method of pest control. The susceptibility of various lifestages of Tribolium castaneum (Herbst) to microwave radiation was studied by irradiating infested wheat flour at 3 cm flour bed thickness. All the life stages of T. castaneum were irradiated at five different power levels viz., 136 W, 264 W, 440 W, 616 W and 800 W for 20 s. Eggs were more susceptible to microwave irradiation, whereas the susceptibility of grubs, pupae and adults were comparable. Mortality of all the life stages of T. castaneum increased with the increase in microwave irradiation power. Mortality of egg, grubs, pupae and adults were highest at an irradiation dose of 800 W i.e., 100, 96, 80 and 80%, respectively. Standardization of power, depth of flour bed thickness and duration of irradiation will enable the utilization of household microwave oven for the disinfestation of food grains.

A study of the influence of rainfall dataset's spatial resolution on stream simulation in Chaliyar River Basin, India

Abstract: Rainfall is a vital input to model watershed hydrology, and the availability of numerous gridded and point-observed rainfall datasets poses a major challenge to the modellers to choose the appropriate data. This study compares three gridded rainfall datasets (i.e., 1° × 1°, 0.5° × 0.5°, and 0.25° × 0.25°) and point rainfall observations of the India Meteorological Department (IMD) on the simulation of streamflow of a river basin in the southern Western Ghats (India) using Soil and Water Assessment Tool (SWAT). The results show that the different data sets lead to different optimal model parameter values and consequent water balance components, significantly in groundwater hydrology. The 0.5° × 0.5° and 0.25° × 0.25° datasets result in comparable SWAT model performances (NSE = 0.75 and 0.70, respectively), probably due to the similarity in the rain gauge network density employed for deriving the datasets and also due to the spatial discretization threshold used for sub-watershed delineation. However, the coarser resolution data (1° × 1°) results in poor performance (NSE = 0.21). The study suggests that the choice of rainfall data depends on the spatial resolution of the data and the spatial discretization threshold while compromising the computational requirement vis-à-vis simulation accuracy.

Engendering Agricultural Development Dimensions and Strategies

Abstract: This book is an attempt to comprehend and compile the history, present status, and future trends of the gender roles in agriculture. The book comprises of three divisions viz., Gender in agriculture development (Part I), Gender in allied sectors of agriculture (Part II) and Data, Tools and approaches in gender analysis (Part III), that explicates the prevalent gendered relegations. It provides insights on the gender dimensions in Indian agriculture, including initiatives, policy reforms and mends the literature gap in gender roles in the sector. The gender roles and impacts from different cultural and geographical horizons of agricultural and allied sectors in the emerging contexts of globalization, urbanization, climate change and the Covid19 pandemic are discussed in the book. It will be helpful to academics, researchers, students, and social workers who strive towards a gender-neutral world. Print and electronic editions not for sale in South Asia (India, Sri Lanka, Nepal, Bangladesh, Pakistan, Afghanistan and Bhutan). © 2023 New India Publishing Agency. All rights reserved.