Nolan, R, Tarin, T, Rumman, R, Cleverly, J, Fairweather, KA, Zolfaghar, S, Santini, NS, O'Grady, AP & Eamus, D 2018, 'Contrasting ecophysiology of two widespread arid zone tree species with differing access to water resources', Journal of Arid Environments, vol. 153, pp. 1-10.View/Download from: UTS OPUS or Publisher's site
Zolfaghar, S, Villalobos-Vega, R, Zeppel, M, Cleverly, J, Rumman, R, Hingee, M, Boulain, N, Li, Z, Eamus, D & Tognetti, R 2017, 'Transpiration of Eucalyptus woodlands across a natural gradient of depth-to-groundwater', Tree Physiology, vol. 37, no. 7, pp. 961-975.View/Download from: UTS OPUS or Publisher's site
Hingee, MC, Eamus, D, Krix, DW, Zolfagher, S & Murray, BR 2017, 'Patterns of plant species composition in mesic woodlands are related to a naturally occurring depth-to-groundwater gradient', Community Ecology, vol. 18, pp. 21-30.View/Download from: UTS OPUS
Zolfaghar, S, Villalobos-Vega, R, Cleverly, J & Eamus, D 2015, 'Co-ordination among leaf water relations and xylem vulnerability to embolism of Eucalyptus trees growing along a depth-to-groundwater gradient', TREE PHYSIOLOGY, vol. 35, no. 7, pp. 732-743.View/Download from: UTS OPUS or Publisher's site
Zolfaghar, S, Villalobos-Vega, R, Zeppel, M & Eamus, D 2015, 'The hydraulic architecture of Eucalyptus trees growing across a gradient of depth-to-groundwater', FUNCTIONAL PLANT BIOLOGY, vol. 42, no. 9, pp. 888-898.View/Download from: UTS OPUS or Publisher's site
Eamus, D, Zolfaghar, S, Villalobos-Vega, R, Cleverly, J & Huete, A 2015, 'Groundwater-dependent ecosystems: recent insights from satellite and field based studies', Hydrology and Earth System Sciences, vol. 19, pp. 4229-4256.View/Download from: UTS OPUS or Publisher's site
Groundwater-dependent ecosystems (GDEs) are at risk globally due to unsustainable levels of groundwater extraction, especially in arid and semi-arid regions. In this review, we examine recent developments in the ecohydrology of GDEs with a focus on three knowledge gaps: (1) how
do we locate GDEs, (2) how much water is transpired from shallow aquifers by GDEs and (3) what are the responses of GDEs to excessive groundwater extraction? The answers to these questions will determine water allocations that are required to sustain functioning of GDEs and to guide regulations on groundwater extraction to avoid negative impacts on
We discuss three methods for identifying GDEs: (1) techniques relying on remotely sensed information; (2) fluctuations in depth-to-groundwater that are associated with diurnal variations in transpiration; and (3) stable isotope analysis of water sources in the transpiration stream. We then discuss several methods for estimating rates of GW use, including direct measurement using sapflux or eddy covariance technologies, estimation of a climate wetness index within a Budyko framework, spatial distribution of evapotranspiration (ET) using remote sensing, groundwater modelling and stable isotopes. Remote sensing methods often rely on direct measurements to calibrate the relationship between
vegetation indices and ET. ET from GDEs is also determined using hydrologic models of varying complexity, from the White method to fully coupled, variable saturation models. Combinations of methods are typically employed to obtain clearer insight into the components of groundwater discharge in GDEs, such as the proportional importance of
transpiration versus evaporation (e.g. using stable isotopes) or from groundwater versus rainwater sources. Groundwater extraction can have severe consequences for the structure and function of GDEs. In the most extreme cases, phreatophytes experience crown dieback and death
following groundwater drawdown.We provide a brief...
Zolfaghar, S, Villalobos-Vega, R, Cleverly, J, Zeppel, M, Rumman, R & Eamus, D 2014, 'The influence of depth-to-groundwater on structure and productivity of Eucalyptus woodlands', AUSTRALIAN JOURNAL OF BOTANY, vol. 62, no. 5, pp. 428-437.View/Download from: UTS OPUS or Publisher's site
Yunusa, IA, Zolfaghar, S, Zeppel, MJ, Li, Z, Palmer, A & Eamus, D 2012, 'Fine root biomass and its relationship to evapotranspiration in woody and grassy vegetation covers for ecological restoration of waste storage and mining landscapes', Ecosystems, vol. 15, no. 1, pp. 113-127.View/Download from: UTS OPUS or Publisher's site
Production and distribution of fine roots (<= 2.0 mm diameter) are central to belowground ecological processes. This is especially true where vegetation serves as a pump to prevent saturation of soil and possible drainage of excess water into or from potentially toxic waste material stored underground or in mounds aboveground. In this study undertaken near Sydney in Australia, we determined fine root biomass and evapotranspiration (ET) on a waste disposal site restored with either a 15-year-old grass sward or plantations of mixed woody species that were either 5 years old (plantation-5) with a vigorous groundcover of pasture legumes and grasses, or 3 years old (plantation-3) with sparse groundcover. These sites were compared with nearby remnant woodland; all four were located within 0.5-km radius at the same site. Ranking of fine root biomass was in the order woodland (12.3 Mg ha(-1)) > plantation-5 (8.3 Mg ha(-1)) > grass (4.9 Mg ha(-1)) > plantation-3 (1.2 Mg ha(-1)) and was not correlated with nutrient contents in soil or plants, but reflected the form and age of the vegetation covers. Trends in root length density (RLD) and root area index (RAI) followed those in root biomass, but the differences in RAI were larger than those in biomass amongst the vegetation covers. Annual ET in the dry year of 2009 was similar in the three woody vegetation covers (652-683 mm) and was at least 15% larger than for the grass (555 mm), which experienced restrained growth in winter and periodic mowing. This resulted in drainage from the grass cover while there was no drainage from any of the woody vegetation covers.