impactsof bushfires on ecologicalprocesses and relationships between productivity andbiodiversity
carbon and nutrientcyclingin forests and semi-aridecosystems, includingthe Pilbara
litterdecomposition and ecosystemfunctioning, includingorganicmatterinputs in to streams
constraints to waterand nutrientacquisition and use bytrees undera range ofconditions
the ecologicalwaterrequirements ofriparian ecosystems
understanding vegetationresponse to climatechangeusing tree ringsto construct climates(dendroclimatology)
Most research that weundertakeis stronglyfield-based,with study sites across muchof WA.Wecomplementourfield studies with comprehensive analyticalworkin the laboratoryand in the glasshouse. Projectideasfor2009-pleasefeelfreetodiscussanyotherideasthatyoumaywanttopursuewithPauline, Matthias or Greg
How lowcan you go?: Vulnerability to cavitation in Australian conifers &shrubs (with DrTimBleby&DrJochen Schenk)
Vulnerabilityorresistance to cavitation (the developmentof‘airbubbles’in xylem)is an importanttraitofdroughttolerance. This projectwould examine vulnerabilityto cavitation in a range ofspecies across arainfallgradientand within an evolutionarycontextand explore whetherlowervulnerabilityhelps explainthe abilityofdifferentgenera to survive in arid environments.
Litter decomposition and rootinteractions under Allocasuarina fraseriana
Allocasuarina fraseriana is a fire-sensitive species in the understoreyofjarrah (Eucalyptus marginata)forest.Actinorhizalroots often proliferate throughthe litterand probablycontribute to Nacquisition andlitterdecomposition. This projectwillcharacterise aspects oflitterqualityand decomposition bylookingatdifferentchemicaland biologicalindices includingroot-microbe associations and howthese associationsmayaffectnitrogencyclingprocesses.
Hydraulic structure and function ofdeep roots oftalltrees
Deep roots are the keyto success formanylarge tree species thatgrow in seasonallydryenvironments,yetweknow nextto nothingabouthowdeep roots are constructed orhowtheywork. This projectwouldexamine the structuraland functionalcharacteristics ofdeep roots thatallowtalltrees to efficientlyuptakeand transportwaterfromdeep in the soilprofile. The projectwould include samplingdeep roots ofkarritrees viacavesystems in the southwestofWA.Rootsegments would be measured in the laboratoryfor(1)xylemanatomyusingmicroscopytechniques (xylemvessels are the microscopic'pipes'plants use totransportwater), (2)howefficientlytheyconductwater, and (3)how vulnerable theyare to cavitation (thedevelopmentof'airbubbles'in xylem). The aimofthe projectwould be to compare deep and shallowrootsand assess howthe numberand width ofxylemvessels relates to the amountofwaterthatcan betransported (hydraulicefficiency)and the likelihood thatwatertransportmaybreakdown due to cavitationunderdroughtconditions (hydraulicsafety). This projectwould be co-supervised byDrTimBleby,Research Associate in the SchoolofPlantBiology(firstname.lastname@example.org). Otherpossible research topics:
Oxygen isotopes ofsediments as records ofenvironmentalchange
Plantspecies effects on organicmattercyclingin freshwaterbodies in WA(with CSIRO Land &Water)
Predictingcanopyleafarea in plantations and native forest
Nutrientcyclingin termitemounds and antnests
PROFESSORRICHARDHOBBS,RESEARCHASSISTANTPROFESSORRACHELSTANDISH,DR JODI PRICE,DR MELINDA MOIR, DR MIKE PERRING,DR LEONIE VALENTINE
RoomG.33 BotanyBuilding;Ph 6488 4691;Email:email@example.comEcosystemRestoration &InterventionEcologyResearchGroup(ERIE)http://www.erie-research.org/index.html PLANT ECOLOGYAPPLIED TOCONSERVATION &RESTORATION South-western Australian ecosystems are remarkable on a globalscale fortheirfloristic diversityand thestrongabiotic controls on ecosystemprocesses—nutrient-impoverished soils, summerdrought, fire. Forthese reasons, theyare valuable “end points” forunderstandingmanyofthe keyecologicaltheories thatunderpin ecologicalrestoration. Yetourabilityto restore these ecosystems is limited bythe veryqualitiesthatmake these ecosystems so unique. This means thatsouth-western Australia is a veryinterestingandchallengingplace fora restoration ecologistto work! Research in the Hobbs lab is grounded in theorybutdriven byan interestin developingpracticaloutcomesforrestoration in a rapidlychangingworld. We use an experimentalapproach to research thatis informed byobservations ofwhatoccurs in nature and weencourage students to do the same. We have listed someprojects and co-supervisors below. These projects include a mix offieldwork, lab workand/orglasshouseexperiments. Also, we are happyto help students develop theirown ideas as longas these fitwithin thebroadlydefined research interests wehave described above. Atrait-based approach to jarrah forestrestoration
There is increasinginterestin usinga traitapproach to understand the restoration ofecosystemfunctions.Traits determine howspecies respond to theirenvironmentand also howtheyaffectecosystemfunctions.Examples ofplanttraits are seed size, life form, palatabilityand fire response. The aimofthis projectwouldbe to measure the traits ofcommon jarrah forestspecies to determine ifthe traits represented in restoredjarrah forestweresimilarto those represented in the reference (unmined)jarrah forest. The projectwouldinvolve a mix offield and laboratory-based research and would be supervised byAsst. Prof.RachelStandishand DrMatthew Daws (Alcoa ofAustralia). Multi-trophic responses to restoration
This is partofa largerprojectusinga trait-based approach to determine the differentresponses ofvariousinteractinggroups to old-field restoration. The old-field restoration site is located atthe UWA future farm(Ridgefield). To date, the traits ofherbaceous plants and herbivorous insects have been assessed. Thestudentwould be required to record and assess changes in the traits (e.g., winglength, bodyweight, etc)ofthe nexttrophic levelfromsamples alreadycollected;the parasitoides and/orpredators (e.g.,wasps,spiders). The studentwillthen relate anytraitpatterns to those oflowertrophic levels and determinewhatsynergies are presentin recolonisation success. Nobackgroundknowledge ofinvertebrates is required,however, an enthusiasmto learn is essential. This projectwould be supervised byDrMelinda Moirand DrJodiPrice.