Isolating the impacts of anthropogenic water use within the hydrological regime of north India
Author(s)
Type
Journal Article
Abstract
The effects of anthropogenic water use play a significant role in determining the hydrological cycle of north India. This paper explores anthropogenic impacts within the regions’ hydrological regime by explicitly including observed human water use behaviour, irrigation infrastructure and the natural environment in the CHANSE (Coupled Human And Natural Systems Environment) socio‐hydrological modelling framework. The model is constrained by observed qualitative and quantitative information collected in the study area, along with climate and socio‐economic variables from additional sources. Four separate scenarios, including business as usual (BAU, representing observed irrigation practices), groundwater irrigation only (where the influence of the canal network is removed), canal irrigation only (where all irrigation water is supplied by diverted surface water) and rainfed only (where all human interventions are removed) are used. Under BAU conditions the modelling framework closely matched observed groundwater levels. Following the removal of the canal network, which forces farmers to rely completely on groundwater for irrigation, water levels decrease, while under a canal only scenario flooding occurs. Under the rainfed only scenario, groundwater levels similar to current business as usual conditions are observed, despite much larger volumes of recharge and discharge entering and leaving the system under BAU practices. While groundwater abstraction alone may lead to aquifer depletion, the conjunctive use of surface and groundwater resources, which includes unintended contributions of canal leakage, create conditions similar to those where no human interventions are present. Here, the importance of suitable water management practices, in maintaining sustainable water resources, are shown. This may include augmenting groundwater resources through managed aquifer recharge and reducing the impacts on aquifer resources through occasional canal water use where possible. The importance of optimal water management practices that highlight trade‐offs between environmental impact and human wellbeing are shown, providing useful information for policy makers, water managers and users.
Date Issued
2020-04
Date Acceptance
2019-12-08
Citation
Earth Surface Processes and Landforms, 2020, 45 (5), pp.1217-1228
ISSN
0197-9337
Publisher
Wiley
Start Page
1217
End Page
1228
Journal / Book Title
Earth Surface Processes and Landforms
Volume
45
Issue
5
Copyright Statement
This article is protected by copyright. All rights reserved.
Sponsor
Natural Environment Research Council (NERC)
Identifier
https://onlinelibrary.wiley.com/doi/abs/10.1002/esp.4799
Grant Number
NE/N01670X/1
Subjects
Science & Technology
Physical Sciences
Geography, Physical
Geosciences, Multidisciplinary
Physical Geography
Geology
socio-hydrological model
water resources
hydrological cycle
human impacts
irrigation water use
groundwater
canals
GROUNDWATER IRRIGATION
BIHAR PLAINS
ROOT-GROWTH
BASIN
DEPLETION
DYNAMICS
CLIMATE
SURFACE
YIELD
0403 Geology
0406 Physical Geography and Environmental Geoscience
Geography
Publication Status
Published
Article Number
esp.4799
Date Publish Online
2019-12-21