ORCID Profile
0000-0003-1755-7334
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Research Topics
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Top 5 Research Topics
ANZSRC Field of Research (FoR)
Physical Geography and Environmental Geoscience | Surface Processes | Surfacewater Hydrology | Forestry Management and Environment | Applied Hydrology (Drainage, Flooding, Irrigation, Quality, Etc.) | Geomorphology | Surfacewater Hydrology
ANZSRC Socio-Economic Objective (SEO)
Land and water management | Natural Hazards in Mountain and High Country Environments | Land and water management | Forest and Woodlands Water Management | Land and water management | Mountain and High Country Land and Water Management |
Related Links
Publications
Surface runoff and erosion after prescribed burning and the effect of different fire regimes in forests and shrublands: A review
Publisher: CSIRO Publishing
Date: 2012
DOI: 10.1071/WF11160
Abstract: This paper examines the state of knowledge about the effects of prescribed burning on surface runoff and erosion at point to catchment scales in forests and shrublands. Fires can increase surface runoff and erosion by removing vegetation, changing soil hydrologic properties and providing a readily erodible layer of sediment and ash. Catchment-scale studies in prescribed-burnt areas usually report minimal impacts from the burn. However, measurements at smaller spatial scales suggest that large changes to hydrologic properties and processes do occur, and a debris-flow ex le from Australia demonstrates that large catchment-scale impacts are possible. It appears that existing catchment-scale studies in prescribed burns do not capture these large events as the s le size (i.e. number of studies) is too small relative to the infrequency of such events. Furthermore, numerous knowledge gaps across all spatial scales limit understanding of the processes contributing to post-prescribed burn runoff and erosion. Understanding the influence of fire regime characteristics on post-fire runoff and erosion is particularly important in the context of prescribed burning, as fire regimes can be manipulated to reduce erosion and water-quality impacts. Therefore, two directions for future research are recommended: (1) process-based studies to understand the factors controlling surface runoff and erosion, particularly in relation to aspects of the fire regime and (2) landscape-scale surveys to quantify large erosion events.
The influence of soil moisture on surface and sub-surface litter fuel moisture simulation at five Australian sites
Publisher: Elsevier BV
Date: 03-2021
Sediment availability on burned hillslopes
Publisher: American Geophysical Union (AGU)
Date: 12-2013
DOI: 10.1002/JGRF.20152
Wildfire and salvage harvesting effects on runoff generation and sediment exports from radiata pine and eucalypt forest catchments, south-eastern Australia
Publisher: Elsevier BV
Date: 02-2011
Probability and Consequence of Postfire Erosion for Treatability of Water in an Unfiltered Supply System
Publisher: American Geophysical Union (AGU)
Date: 2021
DOI: 10.1029/2019WR026185
Abstract: Forested catchments are critical to water supply in major cities. Many of these catchments face the threat of postwildfire erosion, which can contaminate reservoir water. The aim of this paper is to determine the probability and duration of disruptions to treatability due to runoff‐generated debris flows in the first year after a wildfire, before substantial vegetation recovery takes place. We combine models of reservoir hydrodynamics, postfire erosion, and stochastic rainfall to determine probability and magnitude of sediment concentration at the reservoir water offtake. Central to the paper is our technique for linking model components into a risk framework that gives probabilities to the number of days that the turbidity threshold for treatment is exceeded. The model is applied to the Upper Yarra reservoir, which is the linchpin of the water supply system for Melbourne in SE Australia. However, the framework is applicable to other unfiltered water supply systems where suspended sediment is a risk to treatability. Results show that postwildfire erosion poses a substantial threat, with a relatively high probability (annual exceedance probability = 0.1–0.3) of water being untreatable for year following a high‐severity wildfire. Important factors that influence the risk include postwildfire runoff potential, reservoir temperature, and the amount of clay‐sized grains in eroding headwaters. Assumptions about spatial‐temporal rainfall attributes, reservoir hydrodynamics, and the catchment erosion potential are all important sources of error in our estimate of risk. Our approach to risk quantification will help support planning, risk management, and strategic investment to mitigate impacts.
Shifting States, Altered Fates: Divergent Fuel Moisture Responses after High Frequency Wildfire in an Obligate Seeder Eucalypt Forest
Publisher: MDPI AG
Date: 20-05-2019
DOI: 10.3390/F10050436
Abstract: High frequency wildfires can shift the structure and composition of obligate seeder forests and initiate replacement with alternative vegetation states. In some forests, the alternative stable state is drier and more easily burned by subsequent fires, driving a positive feedback that promotes further wildfire and perpetuates alternative stable states. Mountain Ash (Eucalyptus regnans (F.Muell.)) forests are highly valued for their bio ersity, water, timber and carbon. Fires are a natural part of the lifecycle of these forests, but too frequent fires can eliminate Mountain Ash and trigger a transition to lower stature, non-eucalypt forests which are dominated by understorey species. This study sought to better understand the fuel moisture dynamics of alternative stable states resulting from high frequency wildfires. A vegetation mosaic in the Central Highlands, Victoria created a unique opportunity to measure fuel moisture in adjacent forest stands that differed in overstorey species composition and time since fire. Specifically, we measured fuel moisture and microclimate at two eucalypt sites (9 and 79 years old) and three non-eucalypt sites (two 9 year old and one 79 year old). Fuel availability, defined here as the number of days surface fuels were below 16% and dry enough to ignite and sustain fire, was calculated to estimate flammability. Fuel availability differed between sites, particularly as a function of time since fire, with recently burnt sites available to burn more often (4–17 versus 0–3 days). There were differences in fuel availability between non-eucalypt sites of the same age, suggesting that high frequency fire does not always lead to the same vegetation condition or outcome for fuel availability. This indicates there is potential for both positive and negative flammability feedbacks following state transition depending on the composition of the non-eucalypt state. This is the first study to provide empirical insight into the fuel moisture dynamics of alternative stable states in Mountain Ash forests.
The Role of Fire in the Coevolution of Soils and Temperate Forests
Publisher: American Geophysical Union (AGU)
Date: 08-2020
DOI: 10.1029/2019WR026005
Abstract: Climate drives the coevolution of vegetation and the soil that supports it. Wildfire dramatically affects many key eco‐hydro‐geomorphic processes, but its potential role in coevolution of soil‐forest systems has been largely overlooked. The steep landscapes of southeastern Australia provide an excellent natural laboratory to study the role of fire in the coevolution of soil and forests, as they are characterized by temperate forest types, fire frequencies, and soil depths that vary systematically with aridity. The aims of this study were (i) to test the hypothesis that in Southeastern Australia, fire‐related processes are critical to explain the variations in coevolved soil‐forest system states across an aridity gradient and (ii) to identify the key processes and (iii) feedbacks involved. To achieve these aims, we developed a numerical model that simulates the coevolution of soil‐forest systems which employ eco‐hydro‐geomorphic processes that are typical of the flammable forests of southeastern Australia. A stepwise model evaluation, using measurements and published data, confirms the robustness of the model to simulate eco‐hydro‐geomorphic processes across the aridity gradient. Simulations that included fire replicated patterns of observed soil depth and forest cover across an aridity gradient, supporting our hypothesis. The contribution of fire to coevolution increased in magnitude with aridity, mainly due to the higher fire frequency and lower post‐fire infiltration capacity, increasing the rates of fire‐related surface runoff and erosion. Our results show that critical feedbacks between soil depth, vegetation, and fire frequency dictate the trajectory and pace of the coevolution of flammable temperate forests and soils.
Climate Dictates Magnitude of Asymmetry in Soil Depth and Hillslope Gradient
Publisher: American Geophysical Union (AGU)
Date: 07-07-2018
DOI: 10.1029/2018GL077629
Wildfire effects on water quality in forest catchments: A review with implications for water supply
Publisher: Elsevier BV
Date: 2011
Evidence of debris flow occurrence after wildfire in upland catchments of south-east Australia
Publisher: Elsevier BV
Date: 02-2011
Estimating catchment-scale impacts of wildfire on sediment and nutrient loads using the E2 catchment modelling framework
Publisher: Elsevier BV
Date: 07-2011
Predicting sediment delivery from debris flows after wildfire
Publisher: Elsevier BV
Date: 12-2015
Quantifying relations between surface runoff and aridity after wildfire
Publisher: Wiley
Date: 18-04-2018
DOI: 10.1002/ESP.4370
Effects of fire severity and burn patchiness on hillslope-scale surface runoff, erosion and hydrologic connectivity in a prescribed burn
Publisher: Elsevier BV
Date: 12-2013
Fire Effects on Soil Properties
Publisher: CSIRO Publishing
Date: 2019
Abstract: Wildland fires are occurring more frequently and affecting more of Earth's surface than ever before. These fires affect the properties of soils and the processes by which they form, but the nature of these impacts has not been well understood. Given that healthy soil is necessary to sustain bio ersity, ecosystems and agriculture, the impact of fire on soil is a vital field of research. Fire Effects on Soil Properties brings together current research on the effects of fire on the physical, biological and chemical properties of soil. Written by over 60 international experts in the field, it includes ex les from fire-prone areas across the world, dealing with ash, meso and macrofauna, smouldering fires, recurrent fires and management of fire-affected soils. It also describes current best practice methodologies for research and monitoring of fire effects and new methodologies for future research. This is the first time information on this topic has been presented in a single volume and the book will be an important reference for students, practitioners, managers and academics interested in the effects of fire on ecosystems, including soil scientists, geologists, forestry researchers and environmentalists.
How soil temperatures during prescribed burning affect soil water repellency, infiltration and erosion
Publisher: Elsevier BV
Date: 09-2016
Carbon loads, forms and sequestration potential within ash deposits produced by wildfire: new insights from the 2009 ‘Black Saturday’ fires, Australia
Publisher: Springer Science and Business Media LLC
Date: 10-02-2012
Performance of GEDI Space-Borne LiDAR for Quantifying Structural Variation in the Temperate Forests of South-Eastern Australia
Publisher: MDPI AG
Date: 28-07-2022
DOI: 10.3390/RS14153615
Abstract: Monitoring forest structural properties is critical for a range of applications because structure is key to understanding and quantifying forest biophysical functioning, including stand dynamics, evapotranspiration, habitat, and recovery from disturbances. Monitoring of forest structural properties at desirable frequencies and cost globally is enabled by space-borne LiDAR missions such as the global ecosystem dynamics investigation (GEDI) mission. This study assessed the accuracy of GEDI estimates for canopy height, total plant area index (PAI), and vertical profile of plant area volume density (PAVD) and elevation over a gradient of canopy height and terrain slope, compared to estimates derived from airborne laser scanning (ALS) across two forest age-classes in the Central Highlands region of south-eastern Australia. ALS was used as a reference dataset for validation of GEDI (Version 2) dataset. Canopy height and total PAI analyses were carried out at the landscape level to understand the influence of beam-type, height of the canopy, and terrain slope. An assessment of GEDI’s terrain elevation accuracy was also carried out at the landscape level. The PAVD profile evaluation was carried out using footprints grouped into two forest age-classes, based on the areas of mountain ash (Eucalyptus regnans) forest burnt in the Central Highlands during the 1939 and 2009 wildfires. The results indicate that although GEDI is found to significantly under-estimate the total PAI and slightly over-estimate the canopy height, the GEDI estimates of canopy height and the vertical PAVD profile (above 25 m) show a good level of accuracy. Both beam-types had comparable accuracies, with increasing slope having a slightly detrimental effect on accuracy. The elevation accuracy of GEDI found the RMSE to be 10.58 m and bias to be 1.28 m, with an R2 of 1.00. The results showed GEDI is suitable for canopy densities and height in complex forests of south-eastern Australia.
Estimation of surface dead fine fuel moisture using automated fuel moisture sticks across a range of forests worldwide
Publisher: CSIRO Publishing
Date: 2020
DOI: 10.1071/WF19061
Abstract: Field measurements of surface dead fine fuel moisture content (FFMC) are integral to wildfire management, but conventional measurement techniques are limited. Automated fuel sticks offer a potential solution, providing a standardised, continuous and real-time measure of fuel moisture. As such, they are used as an analogue for surface dead fine fuel but their performance in this context has not been widely evaluated. We assessed the ability of automated fuel sticks to predict surface dead FFMC across a range of forest types. We combined concurrent moisture measurements of the fuel stick and surface dead fine fuel from 27 sites (570 s les), representing nine broad forest fuel categories. We found a moderate linear relationship between surface dead FFMC and fuel stick moisture for all data combined (R2=0.54), with fuel stick moisture averaging 3-fold lower than surface dead FFMC. Relationships were typically stronger for in idual forest fuel categories (median R2=0.70 range=0.55–0.87), suggesting the sticks require fuel-specific calibration for use as an analogue of surface dead fine fuel. Future research could identify fuel properties that will enable more generalised calibration functions.
Conditional Performance Evaluation: Using Wildfire Observations for Systematic Fire Simulator Development
Publisher: MDPI AG
Date: 06-04-2018
DOI: 10.3390/F9040189
Modeling the effects of surface storage, macropore flow and water repellency on infiltration after wildfire
Publisher: Elsevier BV
Date: 05-2014
Critical climate thresholds for fire in wet, temperate forests
Publisher: Elsevier BV
Date: 06-2023
Spatio-temporal transpiration patterns reflect vegetation structure in complex upland terrain
Publisher: Elsevier BV
Date: 12-2019
DOI: 10.1016/J.SCITOTENV.2019.07.357
Abstract: Topography exerts control on eco-hydrologic processes via alteration of energy inputs due to slope angle and orientation. Further, water availability varies with drainage position in response to topographic water redistribution and the catena effect on soil depth and thus soil water storage capacity. Our understanding of the spatio-temporal dynamics and drivers of transpiration patterns in complex terrain is still limited by lacking knowledge of how systematic interactions of energy and moisture patterns shape ecosystem state and water fluxes and adaptation of the vegetation to these patterns. To untangle the effects of slope orientation and hillslope position on forest structure and transpiration patterns, we measured forest structure, sap flux, soil moisture, throughfall and incoming shortwave radiation along two downslope transects in a forested head water catchment in south-east Australia. Our plot locations controlled for three systematically varying drainage position levels (topographic wetness index: 5.0, 6.5 and 8.0) and two levels of energy input (aridity index: 1.2 and 1.8). Vegetation patterns were generally stronger related to drainage position than slope orientation, whereas sap velocity variations were less pronounced. However, in combination with stand sapwood area, consistent spatio-temporal transpiration patterns emerged in relation to landscape position, where slope orientation was the primary and drainage position the secondary controlling factor. On short temporal scales, radiation and vapor pressure deficit were most important in regulating transpiration rates, whereas soil water limitation only occurred on shallow soils during summer. The importance of stand structural parameters increased on longer time scales, indicating optimization of vegetation in response to the long-term hydro-climatic conditions at a given landscape position. Thus, vegetation patterns can be conceptualized as a 'time-integrated' predictor variable that captures large fractions of other factors contributing to transpiration patterns.
Evaluating models of shortwave radiation below Eucalyptus canopies in SE Australia
Publisher: Elsevier BV
Date: 11-2017
A model for assessing water quality risk in catchments prone to wildfire
Publisher: Elsevier BV
Date: 03-2016
Modeling Vegetation Water Stress over the Forest from Space: Temperature Vegetation Water Stress Index (TVWSI)
Publisher: MDPI AG
Date: 17-11-2021
DOI: 10.3390/RS13224635
Abstract: The conventional Land Surface Temperature (LST)–Normalized Difference Vegetation Index (NDVI) trapezoid model has been widely used to retrieve vegetation water stress. However, it has two inherent limitations: (1) its complex and computationally intensive parameterization for multi-temporal observations and (2) deficiency in canopy water content information. We tested the hypothesis that an improved water stress index could be constructed by the representation of canopy water content information to the LST–NDVI trapezoid model. Therefore, this study proposes a new index that combines three indicators associated with vegetation water stress: canopy temperature through LST, canopy water content through Surface Water Content Index (SWCI), and canopy fractional cover through NDVI in one temporally transferrable index. Firstly, a new optical space of SWCI–NDVI was conceptualized based on the linear physical relationship between shortwave infrared (SWIR) and soil moisture. Secondly, the SWCI–NDVI feature space was parameterized, and an index d(SWCI, NDVI) was computed based on the distribution of the observations in the SWCI–NDVI spectral space. Finally, standardized LST (LST/long term mean of LST) was combined to d(SWCI, NDVI) to give a new water stress index, Temperature Vegetation Water Stress Index (TVWSI). The modeled soil moisture from the Australian Water Resource Assessment—Landscape (AWRA-L) and Soil Water Fraction (SWF) from four FLUXNET sites across Victoria and New South Wales were used to evaluate TVWSI. The index TVWSI exhibited a high correlation with AWRA-L soil moisture (R2 of 0.71 with p 0.001) and the ground-based SWF (R2 of 0.25–0.51 with p 0.001). TVWSI predicted soil moisture more accurately with RMSE of 21.82 mm (AWRA-L) and 0.02–0.04 (SWF) compared to the RMSE ranging 28.98–36.68 mm (AWRA-L) and 0.03–0.05 (SWF) were obtained for some widely used water stress indices. The TVWSI could also be a useful input parameter for other environmental models.
Forest Structure Drives Fuel Moisture Response across Alternative Forest States
Publisher: MDPI AG
Date: 15-08-2021
DOI: 10.3390/FIRE4030048
Abstract: Climate warming is expected to increase fire frequency in many productive obligate seeder forests, where repeated high-intensity fire can initiate stand conversion to alternative states with contrasting structure. These vegetation–fire interactions may modify the direct effects of climate warming on the microclimatic conditions that control dead fuel moisture content (FMC), which regulates fire activity in these high-productivity systems. However, despite the well-established role of forest canopies in buffering microclimate, the interaction of FMC, alternative forest states and their role in vegetation–fire feedbacks remain poorly understood. We tested the hypothesis that FMC dynamics across alternative states would vary to an extent meaningful for fire and that FMC differences would be attributable to forest structural variability, with important implications for fire-vegetation feedbacks. FMC was monitored at seven alternative state forested sites that were similar in all aspects except forest type and structure, and two proximate open-weather stations across the Central Highlands in Victoria, Australia. We developed two generalised additive mixed models (GAMMs) using daily independent and autoregressive (i.e., lagged) input data to test the importance of site properties, including lidar-derived forest structure, in predicting FMC from open weather. There were distinct differences in fuel availability (days when FMC 16%, dry enough to sustain fire) leading to positive and negative fire–vegetation feedbacks across alternative forest states. Both the independent (r2 = 0.551) and autoregressive (r2 = 0.936) models ably predicted FMC from open weather. However, substantial improvement between models when lagged inputs were included demonstrates nonindependence of the automated fuel sticks at the daily level and that understanding the effects of temporal buffering in wet forests is critical to estimating FMC. We observed significant random effects (an analogue for forest structure effects) in both models (p 0.001), which correlated with forest density metrics such as light penetration index (LPI). This study demonstrates the importance of forest structure in estimating FMC and that across alternative forest states, differences in fuel availability drive vegetation–fire feedbacks with important implications for forest flammability.
Scale‐dependency of effective hydraulic conductivity on fire‐affected hillslopes
Publisher: American Geophysical Union (AGU)
Date: 07-2016
DOI: 10.1002/2016WR018998
Exploring the key drivers of forest flammability in wet eucalypt forests using expert-derived conceptual models
Publisher: Springer Science and Business Media LLC
Date: 24-06-2020
Paired Eucalyptus forest catchment study of prescribed fire effects on suspended sediment and nutrient exports in south-eastern Australia
Publisher: CSIRO Publishing
Date: 2010
DOI: 10.1071/WF08208
Abstract: The effect of prescribed fire on suspended sediment and nutrient exports was investigated in two small Eucalyptus forest catchments in south-eastern Australia. In 2005, a patchy, mostly low-severity prescribed fire was applied to both catchments, followed in 2006 by a second burn applied to riparian areas of one catchment, with the other catchment utilised as a control for this burn. Historic pre-fire weekly stream water s ling was combined with post-fire weekly and storm-based s ling to quantify the effect of the fires. The 2005 fire resulted in a significant difference (P = 0.000) in suspended sediment concentrations compared to pre-fire data and generated peak study period suspended sediment (11.5 kg ha–1 year–1) and total phosphorous (0.016 kg ha–1 year–1) exports under near-average rainfall. However, peak suspended sediment exports only slightly exceeded the average annual load from a nearby undisturbed catchment. Well-below-average rainfall in 2006 resulted in lower exports after this burn compared with the 2005 fire. The results highlighted the importance of hydrological conditions for suspended sediment and nutrient exports within the first 12–18 months after prescribed fires, beyond which generally rapid surface vegetation recovery is likely to mitigate any burns effects.
Impacts of wildfire and salvage harvesting on water quality and nutrient exports from radiata pine and eucalypt forest catchments in south-eastern Australia
Publisher: Elsevier BV
Date: 2012
Changes to sediment sources following wildfire in a forested upland catchment, southeastern Australia
Publisher: Wiley
Date: 17-03-2011
DOI: 10.1002/HYP.8050
Quantifying sources of fine sediment supplied to post-fire debris flows using fallout radionuclide tracers
Publisher: Elsevier BV
Date: 02-2012
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Related Funding Activities
Linkage Projects - Grant ID: LP150100654
Start Date: 03-2016
End Date: 12-2020
Amount: $310,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Projects - Grant ID: LP0881993
Start Date: 09-2008
End Date: 12-2012
Amount: $290,000.00
Funder: Australian Research Council
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