Current Research
Mt Buller Resort management Board:
Fate and Ecological Impact of Treated Sewage Effluent from Mount Buller Alpine Resort, Phase VII
(2004/2005)
Australian Research Council (ARC) Linkage Grant: Advanced micro analysis systems for environmental
monitoring (2003-2006) $258,000
Understanding of the behaviour of the nutrients controlling nuisance algae in water bodies is
currently limited by the cost and logistics of collecting and analysing the large numbers of
samples required. This project will focus on the development and evaluation of portable multiparameter
micro analysis systems that will be capable of high frequency measurements from a sampling vessel.
This will enable environmental agencies to perform rapid on-site mapping of nutrients and other
water quality parameters in large water bodies, intensive scale mapping of effluent mixing and
dispersal zones, quick assessment of the impact of dredging and aquaculture, and compliance monitoring
in effluent streams.
Victorian Institute of Chemical Sciences: Detection and Environmental Chemistry of Phosphorus
in Aquatic and Terrestrial Ecosystems (2004-2005) $360,000
This is a joint project between Monash University (A/Prof Ian McKelvie and Dr Mike Grace),
University of Melbourne (Dr Spas Kolev) and RMIT University (Dr Nichola Porter, Dr Julie
Niere, A/Prof barry Meehan).
This project will concentrate on clarifying the fate and transport of a number of important phosphorus
species such as organic phosphorus, phosphine and phosphonate in aquatic and terrestrial systems.
Sediment core studies will be undertaken to assess the conditions under which organic phosphorus
can be released and converted to bioavailable phosphorus. Soil samples will be taken from areas
treated with fertilizers versus those treated with biosolids such as dairy waste, to study the
fate of the phosphorus added by the two different mechanisms. Soil samples will also be taken
from areas treated with phosphorus containing herbicides such phosphonate to study their transport
and phosphate forming potential. Studies will also be conducted to elucidate the poorly understood
role of phosphine in the total cycling of phosphorus. These studies will require the development
and optimization of novel flow injection methods and accompanying field instrumentation. Validation
studies on the speciation of the phosphorus compounds detected will be carried out using 31P
NMR.
Biogeochemistry of organic phosphorus compounds
This research area is studying the biogeochemistry of nutrient species in aquatic systems, with
a particular emphasis on organic phosphorus. Funding has previously been obtained via two ARC
grants: a large ARC grant for a project on Inositol phosphates: their detection and occurrence
in the aquatic environment and a small ARC grant for project on Enzymatic determination
of phospholipids in the aquatic environment. Both projects are developing and applying sensitive
and selective detection techniques for measuring these species in the environment. Phosphohydrolytic
enzymes, such as alkaline phosphatase, phytase and phosphodiesterase, have been investigated
as a means to functionally characterise organic phosphorus. These enzyme methods have been coupled
with a size exclusion technique to separate high and low molecular mass organic phosphorus species
in sediments and soils. This latter technique has been used to study the occurrence of inositolhexakisphosphate
in sediment pore waters and sediment extracts. Although inositolhexakisphosphate can make up
80% of the total phosphorus content in some soils and sediments, it is insoluble and stronglybound
within the sediments, and is therefore effectively biologically unavailable. However, we have
recently found that inositol phosphate and other higher molecular weight (MW) organic phosphorus
compounds are present in sediment interstitial waters, and are also readily released from sediments
at brackish water salinities (>5 ppt). Further research in this area will concentrate on defining
the physicochemical conditions that favour organic phosphorus release, and on assessing the bioavailability
of this released organic phosphorus. |
