Assessment of agricultural water security for different agro-ecosystems using analytic hierarchy process

Abstract

Water security is the ability to access sufficient quantities and qualities of water to maintain adequate standards of food and goods production, proper sanitation and sustainable health care. Water logging, salinity, etc. are among the major factors that hamper agricultural production and hence influence water security in the south-west coastal region of Bangladesh. Sea level rise, occurrence of natural disasters, changes in climatic patterns and man-made alteration of natural settings are further deteriorating the water security situation. This study assessed agricultural water security for three selected agro-ecosystems of Tala Upazila of Satkhira district and suggested suitable strategies to improve the security. The study followed an interdisciplinary approach to produce an integrated assessment of water security, linking physical dimensions of water availability with socioeconomic variables that reflect water security. Five components of water security like water availability, access to water, water use, capacity to use water and disaster management were considered to develop the water security index. Within each major component, there were a number of sub-components. Water security indices were developed using Analytical Hierarchical Approach. Required data and information like source of water for irrigation, adequacy of water, quality of water and existing hazards for agricultural production were collected from the local people using focus group discussion and questionnaire survey, and from the local key informants using semi-structured interview. The agricultural water security index was found to be 2.3 on a scale of 5 at Khanpur, and 2.0 at Kheshra. According to the values, both the agro-ecosystems were water insecured for agricultural production, mainly due to water logging and salinity problems. At Bhorot Bhaena, the index was found to be 4.2 which indicated that the area was water secured for agricultural production. The high value at Bhorot Bhaena was due to the implementation of tidal river management (TRM). Suitable strategies for improving agricultural production at Khanpur were found to be TRM, mixed cropping system and flood-tolerant rice varieties. For Kheshra, the suitable strategies to improve agricultural water security were found to be saline-resistant crop cultivation, rice-prawn farming and rainwater harvesting. Agricultural productivity at Bhorot Bhaena can be further improved using strategies like rainwater harvesting and rice-prawn farming.