UPSC Mains Answer: What is Water-use efficiency? Describe the role of micro-irrigation in increasing the water-use efficiency.

Difficulty Level: Medium

Sub-category: Agriculture (GS-III: Technology, Economic Development, Bio-diversity, Environment, Security and Disa

Introduction

Water-use efficiency (WUE) refers to the ratio of water effectively utilized for a specific purpose, such as agriculture, to the total water applied. In a country like India, where agriculture consumes over 80% of freshwater resources, improving WUE is critical for sustainable water management and food security.

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Concept of WUE

WUE is measured as crop yield per unit of water used. Traditional irrigation methods like flood irrigation lead to significant water loss due to evaporation, runoff, and seepage, resulting in low WUE. Enhancing WUE involves adopting technologies and practices that minimize water wastage while maximizing agricultural productivity.

Role of Micro-Irrigation

Micro-irrigation, including drip and sprinkler systems, plays a transformative role in increasing WUE. Drip irrigation delivers water directly to the plant roots, reducing evaporation and runoff by up to 60%. Sprinkler systems mimic rainfall, ensuring uniform water distribution with minimal loss. These methods not only conserve water but also improve crop yields, reduce soil erosion, and prevent waterlogging. Government schemes like the Pradhan Mantri Krishi Sinchayee Yojana (PMKSY) promote micro-irrigation to enhance WUE, particularly in water-scarce regions like Maharashtra, Rajasthan, and Karnataka.

Additional Benefits

Micro-irrigation also enables precise nutrient application (fertigation), reduces weed growth, and lowers energy costs. It is particularly effective for high-value crops such as fruits, vegetables, and spices, contributing to higher farmer incomes and sustainable agriculture.

Conclusion

In the face of depleting water resources and climate change, improving WUE through micro-irrigation is indispensable for India’s agricultural sustainability. Policymakers, farmers, and stakeholders must collaborate to scale up these technologies, ensuring water security and economic prosperity for future generations.