@article {bnh-4970, title = {Controlled burn and immediate mobilization of potentially toxic elements in soil, from a legacy mine site in Central Victoria, Australia}, journal = {Science of The Total Environment}, volume = {616-617}, year = {2018}, month = {03/2018}, chapter = {1022}, abstract = {

Conducting controlled burns in fire prone areas is an efficient and economic method for forest management, and provides relief from the incidence of high severity wild fires and the consequent damage to human property and ecosystems. However, similar to wild fires, controlled burns also affect many of the physical and biogeochemical properties of the forest soil and may facilitate remobilization of potentially toxic elements (PTEs) sequestered in vegetation and soil organic matter. The objective of the current study is to investigate the mobilization of PTEs, in Central Victorian forest soils in Australia after a controlled burn. Surface soil samples were collected two days before and after the controlled burn to determine the concentration of PTEs and to examine the physicochemical properties. Results show that As, Cd, Mn, Ni and Zn concentrations increased 1.1, 1.6, 1.7, 1.1 and 1.9 times respectively in the post-burn environment, whereas the concentrations of Hg, Cr and Pb decreased to 0.7, 0.9 and 0.9 times respectively, highlighting considerable PTE mobility during and after a controlled burn. Whilst these results do not identify very strong correlations between physicochemical properties of soil and PTEs in the pre- and post-burn environments, PTEs themselves demonstrated very strong and significant correlations. The mobilization of As, Hg and other toxic elements raise potential health concerns as the number of controlled burns are projected to increase in response to climate change. Due to this increased level of PTE release and remobilization, the use of any kinds of controlled burn must be carefully considered before being used as a forest management strategy in mining-affected landscapes which include areas with high PTE concentrations.

}, keywords = {Arsenic and metals, environmental pollution, forest fire, historical mining, prescribed fire, soil and water pollution}, doi = {10.1016}, url = {https://www.sciencedirect.com/science/article/pii/S0048969717329364}, author = {Joji Abraham and Kim Dowling and Singarayer Florentine} } @article {bnh-5401, title = {Influence of controlled burning on the mobility and temporal variations of potentially toxic metals (PTMs) in the soils of a legacy gold mine site in Central Victoria, Australia}, journal = {Geoderma}, volume = {331}, year = {2018}, chapter = {1}, abstract = {

Controlled burns also known as managed burns or prescribed fires conducted in fire-prone areas are an efficient and economic option to reduce the frequency and intensity of\ wildfires. The objective of this study is to investigate the\ remobilizationof potentially\ toxic metals\ (PTMs) in the soils of a legacy\ gold mine\ site in Central Victoria, Australia after a controlled burn and to describe their\ temporal variationsin concentrations. Soil samples were collected two days before, two days after and five times later (3, 6, 9, 12 months and after major rainfall) in the post-burn environment after a controlled burn, from the Maldon legacy mine site and analysed for PTM concentrations. The results revealed PTM mobilization after the burn and most of the PTMs (As, Cd, Cu, Mn, Ni, and Zn) evidenced an increase immediately after the burn but a reduction in the subsequent post-burn environment. The increase is postulated to be associated with addition of PTM enriched ash to the soil, while the decrease is due to the removal of ash and surface soil by wind activity as well as rainfall\ runoff\ and\ leaching. The PTM mobility is of specific concern due to the negative impacts on human and\ ecosystems health.\ Climate change\ and the resulting projection of increased\ forest fire\ frequency highlight the environmental significance, given the expected concomitant increase in PTM mobilization through wildfires and controlled burns. Hence, the practice of controlled burning should be carefully considered as a\ forest management\ option in any legacy mining areas and indeed in other areas where PTM\ contamination\ is reported.

}, keywords = {Ash, forest fire, Forest management, Metal mobility, prescribed fire, Soil and water contamination}, doi = {https://doi.org/10.1016/j.geoderma.2018.06.010}, url = {https://www.sciencedirect.com/science/article/pii/S0016706117320001}, author = {Joji Abraham and Kim Dowling and Singarayer Florentine} } @article {bnh-5403, title = {Risk of post-fire metal mobilization into surface water resources: A review}, journal = {Science of the total Environment}, volume = {599-600}, year = {2017}, abstract = {

One of the significant economic benefits to communities around the world of having pristine forest\ catchments\ is the supply of substantial quantities of high quality potable water. This supports a saving of around US$ 4.1 trillion per year globally by limiting the cost of expensive\ drinking water treatments\ and provision of unnecessary infrastructure. Even low levels of contaminants specifically organics and metals in catchments when in a mobile state can reduce these economic benefits by seriously affecting the water quality.\ Contamination\ and contaminant mobility can occur through natural and anthropogenic activities including\ forest fires. Moderate to high intensity forest fires are able to alter\ soil properties\ and release sequestered metals from sediments,\ soil organic matter\ and fragments of vegetation. In addition, the increase in post-fire\ erosion rate\ by rainfall runoff and strong winds facilitates the rapid transport of these metals downslope and downstream. The subsequent metal deposition in distal soil and water bodies can influence surface water quality with potential impacts to the larger ecosystems inclusive of negative effects on humans. This is of substantial concern as 4 billion hectares of forest catchments provide high quality water to global communities. Redressing this problem requires quantification of the potential effects on water resources and instituting rigorous fire and\ environmental management\ plans to mitigate deleterious effects on catchment areas. This paper is a review of the current state of the art literature dealing with the risk of post-fire mobilization of the metals into surface water resources. It is intended to inform discussion on the preparation of suitable management plans and policies during and after fire events in order to maintain potable water quality in a cost-effective manner. In these times of climate fluctuation and increased incidence of fires, the need for development of new policies and management frameworks are of heighted significance.

}, keywords = {Catchment, Ecosystem, environment, forest fire, Metal, Water resources}, doi = {https://doi.org/10.1016/j.scitotenv.2017.05.096}, url = {https://www.sciencedirect.com/science/article/pii/S0048969717311968}, author = {Joji Abraham and Kim Dowling and Singarayer Florentine} }