TY - JOUR
T1 - Modelling vegetation water-use and groundwater recharge as affected by climate variability in an arid-zone Acacia savanna woodland
AU - Chen, Chao
AU - Eamus, Derek
AU - Cleverly, James
AU - Boulain, Nicolas
AU - Cook, Peter
AU - Zhang, Lu
AU - Cheng, Lei
AU - Yu, Qiang
PY - 2014
Y1 - 2014
N2 - For efficient and sustainable utilisation of limited groundwater resources, improved understanding of how vegetation water-use responds to climate variation and the corresponding controls on recharge is essential. This study investigated these responses using a modelling approach. The biophysically based model WAVES was calibrated and validated with more than two years of field experimental data conducted in Mulga (. Acacia aneura) in arid central Australia. The validated model was then applied to simulate vegetation growth (as changes in overstory and understory leaf area index; LAI), vegetation water-use and groundwater recharge using observed climate data for the period 1981-2012. Due to large inter-annual climatic variability, especially precipitation, simulated annual mean LAI ranged from 0.12 to 0.35 for the overstory and 0.07 to 0.21 for the understory. These variations in simulated LAI resulted in vegetation water-use varying greatly from year-to-year, from 64 to 601. mm pa. Simulated vegetation water-use also showed distinct seasonal patterns. Vegetation dynamics affected by climate variability exerted significant controls on simulated annual recharge, which was greatly reduced to 0-48. mm compared to that (58-672. mm) only affected by climate. Understanding how climate variability and land use/land cover change interactively impact on groundwater recharge significantly improves groundwater resources management in arid and semi-arid regions.
AB - For efficient and sustainable utilisation of limited groundwater resources, improved understanding of how vegetation water-use responds to climate variation and the corresponding controls on recharge is essential. This study investigated these responses using a modelling approach. The biophysically based model WAVES was calibrated and validated with more than two years of field experimental data conducted in Mulga (. Acacia aneura) in arid central Australia. The validated model was then applied to simulate vegetation growth (as changes in overstory and understory leaf area index; LAI), vegetation water-use and groundwater recharge using observed climate data for the period 1981-2012. Due to large inter-annual climatic variability, especially precipitation, simulated annual mean LAI ranged from 0.12 to 0.35 for the overstory and 0.07 to 0.21 for the understory. These variations in simulated LAI resulted in vegetation water-use varying greatly from year-to-year, from 64 to 601. mm pa. Simulated vegetation water-use also showed distinct seasonal patterns. Vegetation dynamics affected by climate variability exerted significant controls on simulated annual recharge, which was greatly reduced to 0-48. mm compared to that (58-672. mm) only affected by climate. Understanding how climate variability and land use/land cover change interactively impact on groundwater recharge significantly improves groundwater resources management in arid and semi-arid regions.
KW - Climate variability
KW - Groundwater recharge
KW - Savanna woodland
KW - Vegetation water-use
KW - WAVES
UR - http://www.scopus.com/inward/record.url?scp=84907688235&partnerID=8YFLogxK
U2 - 10.1016/j.jhydrol.2014.08.032
DO - 10.1016/j.jhydrol.2014.08.032
M3 - Article
SN - 0022-1694
VL - 519
SP - 1084
EP - 1096
JO - Journal of Hydrology
JF - Journal of Hydrology
IS - Part A
ER -