Ecology and Evolutionary Biology Commons^™

Investigating The Effects Of Changes In Light Quality On Different Life History Stages Of Seagrasses, Simone Strydom

Theses: Doctorates and Masters

Seagrass meadows provide crucial ecosystem services to the coastal zone but globally are threatened. Seagrass loss to date has mainly been attributed to anthropogenic activities that reduce light quantity, such as dredging, declining water quality from urban and agricultural run-off and eutrophication. However, light quality (wavelengths of light) is also altered by these anthropogenic stressors as well as natural events. This study consisted of three main components: (1) characterising light quality to which seagrasses are exposed across a local natural estuarine-ocean gradient and with a human impact pressure; (2) the influence of monochromatic light quality (blue λ=451 nm; green λ=522 …

Nocturnal Roost Tree, Roost Site And Landscape Characteristics Of Carnaby's Black-Cockatoo (Calyptorynchus Latirostris) On The Swan Coastal Plain, Candice Le Roux

Theses: Doctorates and Masters

There is limited information on communal roosting in parrot species of Western Australia and other parts of the world. Carnaby’s Black-Cockatoo is an endangered species that forms large nocturnal communal roosts, and for this reason they are an ideal model species to test the characteristics or factors that are associated with roost sites. Known roost sites distributed across the Swan Coastal Plain were identified and selected through the Great Cocky Count project. A minimum of five and maximum of ten individual trees were assessed at 11 roost sites with an overall total of 95 roost trees sampled. I determined the …

Ecology Of Savanna Ecosystems In Indonesia, Sutomo

Theses: Doctorates and Masters

Tropical savannas in South East Asia are important yet understudied ecosystems. In fact, the description of savanna is limited in the Indonesian Archipelago, a region which, based on climate alone, would be expected to have mostly forest. In this thesis, I compared and contrasted the vegetation characteristics of four savannas in the wetter part of the Indonesian archipelago (Java – Bali – Lombok) to understand how fire and grazing influence their dynamics, and searched for evidence of savanna origins, maintenance, invasion by exotic/woody species and possible ecosystem transitions. Vegetation surveys, remote sensing techniques and statistical models were used to spatially …

The Role Of The Seagrass Leaf Microbiome In Assisting Nitrogen Uptake By The Western Australian Seagrass, Posidonia Sinuosa, Flavia Tarquinio

Theses: Doctorates and Masters

Microorganisms play a key role in facilitating the cycling of several elements in coastal environments, including nitrogen (N). N is a key component for maintaining high seagrass productivity and is often the limiting nutrient in marine environments. Seagrasses harbour an abundant and diverse microbial community (the ‘microbiome’), however their ecological and functional roles related to the seagrass host are still poorly understood, in particular regarding N cycling. Microorganisms capable of mineralising dissolved organic nitrogen (DON) may play a pivotal role in enhancing N availability in coastal environments such as seagrass meadows. Thus, the overall aim of my thesis was to …

Fire Was In The Reptile’S Mouth: Towards A Transcultural Ecological Poetics, Stuart Cooke

Landscapes: the Journal of the International Centre for Landscape and Language

This paper compares two creation narratives from indigenous peoples on either side of the Pacific Ocean, the relationships between which catalyse the theorisation of a transcultural approach to ecological poetics. The comparison of these narratives reveals important, rhizomatic similarities, and also unmistakable regional differences, concerning the origins of language and culture in Yanomami (Venezuela) and MakMak (Australia) communities. Concomitant with the centrality of indigenous thought in this theorisation of ecopoetics is the de­centrality of human-only conceptions of poetics. Accordingly, the paper considers non-semantic forms of poetics such as birdsong in order to de-centre classically Western, humanist conceptions of language …

A Profusion Of Parallel Tracks: Why Mongolian Roads Of Dirt And Gravel Branch, Multiply, And Fuse Endlessly, Bill Yake

Landscapes: the Journal of the International Centre for Landscape and Language

A Profusion of Parallel Tracks: Why Mongolian Roads of Dirt and Gravel Branch, Multiply, and Fuse Endlessly

Accelerating Tropicalization And The Transformation Of Temperate Seagrass Meadows, Glenn A. Hyndes, Kenneth L. Heck, Jnr, Adriana Verges, Euan S. Harvey, Gary A. Kendrick, Paul Lavery, Kathryn Mcmahon, Robert J. Orth, Alan Pearce, Mathew Vanderklift, Thomas Wernberg, Scott Whiting, Shaun Wilson

Research outputs 2014 to 2021

Climate-driven changes are altering production and functioning of biotic assemblages in terrestrial and aquatic environments. In temperate coastal waters, rising sea temperatures, warm water anomalies and poleward shifts in the distribution of tropical herbivores have had a detrimental effect on algal forests. We develop generalized scenarios of this form of tropicalization and its potential effects on the structure and functioning of globally significant and threatened seagrass ecosystems, through poleward shifts in tropical seagrasses and herbivores. Initially, we expect tropical herbivorous fishes to establish in temperate seagrass meadows, followed later by megafauna. Tropical seagrasses are likely to establish later, delayed by …

Coastal Connectivity And Spatial Subsidy From A Microbial Perspective, Christin Säwström, Glenn A. Hyndes, Bradley D. Eyre, Megan J. Huggett, Matthew W. Fraser, Paul S. Lavery, Paul G. Thomson, Flavia Tarquinio, P. D. Steinberg, Bonnie Laverock

Research outputs 2014 to 2021

The transfer of organic material from one coastal environment to another can increase production in recipient habitats in a process known as spatial subsidy. Microorganisms drive the generation, transformation, and uptake of organic material in shallow coastal environments, but their significance in connecting coastal habitats through spatial subsidies has received limited attention. We address this by presenting a conceptual model of coastal connectivity that focuses on the flow of microbially mediated organic material in key coastal habitats. Our model suggests that it is not the difference in generation rates of organic material between coastal habitats but the amount of organic …

Asal Usul Formasi Savana: Tinjauan Dari Nusa Tenggara Timur Dan Hasil Penelitian Di Baluran Jawa Timur [Origin Of Savanna Formation: Literature Review From East Nusa Tenggara And Research Results From Baluran East Java Indonesia], Sutomo

Research outputs 2014 to 2021

Savannas are ecosystems mostly confined to tropical and subtropical regions that are characterized by a continuous cover of C₄ grasses that have different characteristics based on seasonality and where woody plants are also an important feature, but with sparse cover and no closed canopy. This is common formation in the driest part of Indonesia such as East Nusa Tenggara, however savana can also be found in Java Island: Baluran Savanna in East Java. There has been considerable amount of debat among scientists, botanists in Indonesia regarding the origin of Indonesian savanna. Using literature study and also field observation at …

Key Biogeochemical Factors Affecting Soil Carbon Storage In Posidonia Meadows, Oscar Serrano, Aurora M. Ricart, Paul S. Lavery, Miguel-Angel Mateo, Ariane Arias-Ortiz, Pere Masque, Mohammad Rozaimi, Andy D. L. Steven, Carlos Duarte

Research outputs 2014 to 2021

Biotic and abiotic factors influence the accumulation of organic carbon (C_org) in seagrass ecosystems.We surveyed Posidonia sinuosa meadows growing in different water depths to assess the variability in the sources, stocks and accumulation rates of C_org. We show that over the last 500 years, P. sinuosa meadows closer to the upper limit of distribution (at 2-4m depth) accumulated 3- to 4-fold higher C_org stocks (averaging 6.3 kgC_org m^-2) at 3- to 4-fold higher rates (12.8 gC_org m^-2 yr^-1/ compared to meadows closer to the deep limits of distribution …

Permanent Slides For Morphological Studies Of Small Crustaceans: Serban's Method And Its Variation Applied On Bathynellacea (Malacostraca), Giulia Perina, Ana I. Camacho

Research outputs 2014 to 2021

Morphological studies of small invertebrates often involve the preparation of slides to observe minute body parts under a compound microscope. Preparation should facilitate observation, through traditional optical microscopy, of small surface structures on different planes, like pores, spines and setae. Various methods and techniques, using different mounting media that specialists have adopted to observe and preserve small crustaceans, have their advantages and disadvantages.Within the order Bathynellacea, specimens in the family Bathynellidae are particularly challenging due to their small size (0.5 to 2.25 mm body length) and very delicate exoskeleton, which tends to be completely digested when using common clearing mounting …

Can Mud (Silt And Clay) Concentration Be Used To Predict Soil Organic Carbon Content Within Seagrass Ecosystems?, Oscar Serrano, Paul Lavery, Carlos Duarte, Gary A. Kendrick, Antoni M. Calfat, P. H. York, Andy D. Steven, Peter I. Macreadie

Research outputs 2014 to 2021

The emerging field of blue carbon science is seeking cost-effective ways to estimate the organic carbon content of soils that are bound by coastal vegetated ecosystems. Organic carbon (C_org) content in terrestrial soils and marine sediments has been correlated with mud content (i.e., silt and clay, particle sizes < 63 µm), however, empirical tests of this theory are lacking for coastal vegetated ecosystems. Here, we compiled data (n =  1345) on the relationship between C_org and mud contents in seagrass ecosystems (79 cores) and adjacent bare sediments (21 cores) to address whether mud can be used to predict soil C_org content. We also combined these data with the δ¹³C signatures of the soil …

Predicting The Impact Of Future Climate On Ecologically Important Macroalgae, Charlie Phelps

Theses: Doctorates and Masters

Macroalgae play an important role in coastal reef systems and are often referred to as ecosystem engineers. They serve as primary producers, supporting a diverse range of organisms, and are a sink for atmospheric CO2. Water acidification and ocean warming caused by anthropogenic activities are affecting many marine flora and fauna, potentially impacting the physical and chemical performance of macroalgae and the consumption rates of associated herbivores. Many studies have focused on ocean acidification or ocean warming individually but there is an overall lack of research investigating the combined effects and the ensuing repercussions on consumer-prey relationships.

Three species of …

Identifying Plant Functional Traits To Assist Ecological Intervention In A Drying Landscape, Ana Luiza Muler

Theses: Doctorates and Masters

Mediterranean-type ecosystems (MTEs) are among the most vulnerable to land use and climate change and many attempts are in place to restore these ecosystems. Therefore, it is necessary to assess differences in plants’ ability to withstand water-stress, including biotic interactions. Such knowledge helps us understand community assembly, which is crucial for ecological intervention. This study involved: (1) reviewing the literature on traits that can differentiate functional types; (2) adapting the methodology to measure leaf water potential at turgor loss point (πtlp) for small-leaved species; (3) using these traits to quickly identify water-use strategies of adult …

Evolution, Systematics & Geographic Parthenogenesis Of Ilyodromus (Crustacea, Ostracoda), Rylan James Shearn

Theses

Most multicellular organisms reproduce sexually at some point in their life cycle. This is paradoxical because being asexual is theoretically far more advantageous. Asexual organisms do not need to find and court new mates, they reproduce at a faster rate, and with no males, all members of the population contribute toward population growth rate. With over 20, often mutually exclusive hypotheses, this paradox resists a synthesised explanation, and continues to represent one of the largest gaps in our understanding of fundamental evolutionary theory. Clearly, more real world studies are required that document the selective mechanisms underlying differences in evolutionary fitness …

Do Water Buffalo Facilitate Dispersal Of Invasive Alien Tree Species Acacia Nilotica In Bekol Savanna Baluran National Park?, Sutomo

Research outputs 2014 to 2021

Invasion of Acacia nilotica in Baluran National Park, East Java Province, Indonesia, has caused significant loss to savanna cover which is the main natural feature of the park. This study aimed to describe whether water buffalo may play a role in the dispersal of Acacia nilotica seed in Bekol Savanna usinganalysis of buffalo stools/scats, observations and seed experiments. In total there were 30 plots set up around the Bekol Savanna to collect buffalo stools. In addition,A. nilotica pods matured from its trees were collected, as controls. Germination tests were conducted on seeds that were extracted from the collected stools …

Climate-Adjusted Provenancing: A Strategy For Climate-Resilient Ecological Restoration, Suzanne M. Prober, Margaret Byrne, Elizabeth H. Mclean, Dorothy A. Steane, Brad M. Potts, Rene E. Vaillancourt, William D. Stock

Research outputs 2014 to 2021

Investments in ecological restoration are estimated at $US 2 trillion per annum worldwide and are increasing rapidly (Cunningham, 2008; Williams et al., 2014). These investments are occurring in an environment of accelerated climate change that is projected to continue into the next century, yet they currently take little account of such change. This has significant implications for the long-term success of restoration plantings across millions of hectares, with germplasm used in current restoration efforts potentially poorly-adapted to future climates. New approaches that optimize the climate-resilience of these restoration efforts are thus essential (Breed et al., 2013; Williams et al., 2014; …

Seagrass Meadows As A Globally Significant Carbonate Reservoir, I Mazarrasa, N Marbà, O Serrano, C E. Lovelock, Paul S. Lavery, J W. Fourqurean, H Kennedy, M A. Mateo, D Krause-Jensen, A D. Steven, C M. Duarte

Research outputs 2014 to 2021

There has been growing interest in quantifying the capacity of seagrass ecosystems to act as carbon sinks as a natural way of offsetting anthropogenic carbon emissions to the atmosphere. However, most of the efforts have focused on the particulate organic carbon (POC) stocks and accumulation rates and ignored the particulate inorganic carbon (PIC) fraction, despite important carbonate pools associated with calcifying organisms inhabiting the meadows, such as epiphytes and benthic invertebrates, and despite the relevance that carbonate precipitation and dissolution processes have in the global carbon cycle. This study offers the first assessment of the global PIC stocks in seagrass …

Dynamics Of Baseline Stable Isotopes Within A Temperate Coastal Ecosystem: Relationships And Projections Using Physical And Biogeochemical Factors, Andrew Mackey

Theses: Doctorates and Masters

Measurements of carbon (13C/12C; δ13C) and nitrogen (15N/14N; δ15N) stable isotope ratios have become important tools for: estimating energy flow and trophic positions in aquatic foodwebs; comparing food webs; and aiding in the tracking of wide-ranging consumers. However, each of these applications requires accurate measurements of isotopic signatures in organisms at or near the base of the food web (e.g. autotrophs and their consumers), which act as basal reference points from which to calibrate inferences. Therefore, understanding variations in isotopic baselines, and the mechanisms leading to their variability, is crucial for food web ecology.

Using the shallow temperate reefs along …

Ecology Of Feral Cats Felis Catus And Their Prey In Relation To Shrubland Fire Regimes, Tim S. Doherty

Theses: Doctorates and Masters

Invasive predators are major drivers of global biodiversity loss and their impacts may be worsened by other disturbances such as fire. I examined how the fire history of shrublands influences the ecology of feral cats Felis catus, dingoes Canis dingo and their prey species in Western Australia’s northern Wheatbelt region.

A review of the literature revealed that feral cats inhabit a diverse range of ecosystems worldwide, but are generally recorded most often in habitat types characterised by a mixture of plant growth forms close to ground level. Cat habitat use is influenced by predation/competition, prey availability, shelter availability and …

Soil Seed Banks Of Fringing Salt Lake Vegetation In Arid Western Australia - Density, Composition And Implications For Postmine Restoration Using Topsoil, Eddie J. Van Etten, Brett Neasham, Sarah Dalgleish

Research outputs 2014 to 2021

Although studies of seed banks in arid ecosystems are commonplace, they are lacking for the large arid zone of Western Australia. Across the six major plant communities fringing a large salt lake within this zone, topsoil (0-5 cm depth) was collected from 12 to 36 sites per community. Samples were dried, spread out on a bed of vermiculite in seedling trays and placed in a well-watered glasshouse to determine the readily germinable component of the soil seed bank. Subsamples of topsoil were treated with smoke water, hot water or flooding to help determine seed bank of species with dormancy mechanisms. …

Behavioural Ecology Of The Black-Flanked Rock-Wallaby (Petrogale Lateralis Lateralis): Refuge Importance In A Variable Environment, Craig Pentland

Theses: Doctorates and Masters

The black-flanked rock-wallaby (Petrogale lateralis lateralis) has suffered a significant decline in its distribution in Western Australia. This has been attributed to introduced predators (predominantly the red fox) and herbivores, fire, and habitat destruction due to clearing. Although since 2001 the Department of Environment and Conservation (DEC) had begun to reintroduce this species back into its former range, little was known of the behavioural ecology of this species. Fox control in the 1980s and 1990s resulted in population increases of rock-wallabies on several reserves in the central wheatbelt of WA. However, recently these populations have rapidly declined despite continuing fox …

The Movement Ecology Of Seagrasses, Kathryn Mcmahon, Kor-Jent Van Dijk, Leonardo Ruiz-Montoya, Gary A. Kendrick, Siegfried L. Krauss, Michelle Waycott, Jennifer Verduin, Ryan Lowe, John Statton, Eloise Brown, Carlos Duarte

Research outputs 2014 to 2021

A movement ecology framework is applied to enhance our understanding of the causes, mechanisms and consequences of movement in seagrasses: marine, clonal, flowering plants. Four life-history stages of seagrasses can move: pollen, sexual propagules, vegetative fragments and the spread of individuals through clonal growth. Movement occurs on the water surface, in the water column, on or in the sediment, via animal vectors and through spreading clones. A capacity for long-distance dispersal and demographic connectivity over multiple timeframes is the novel feature of the movement ecology of seagrasses with significant evolutionary and ecological consequences. The space–time movement footprint of different life-history …

Systematics And Biogeography Of The Australian Burrowing Freshwater Crayfish Genus Engaewa Riekk (Decapoda: Parastacidae), Quinton Burnham

Theses: Doctorates and Masters

The overall aim of this study was to explore the systematics and biogeographic patterns of the freshwater crayfish genus Engaewa Riek, a strongly burrowing freshwater crayfish restricted to the coastal corner of south-western Australia (SWA). The genus Engaewa is a Gondwanan relict with great potential as a marker of historical processes, due to its high habitat specificity and low dispersal ability. This study comprises an extensive taxonomic and phylogenetic revision of the genus Engaewa (using both molecular and morphological data), a detailed study of its distribution and uses the knowledge gained to explore biogeographic patterns in the biodiversity hotspot of …

Influence Of Hydrological And Environmental Conditions On Mangrove Vegetation At Coastal And Inland Semi-Arid Areas Of The Gascoyne Region, Natasha Robin Dunham

Theses: Doctorates and Masters

Mangrove stands are uncommon within semi-arid climates and rare within inland systems. It is uncertain whether the same environmental variables influence mangroves growing in a semi-arid climate as the trees growing in tropical and sub-tropical areas. Field studies conducted on the ecophysiological responses of the mangrove species Avicennia marina are few; however hydrological regimes are considered the key factor influencing mangrove stand zonation, structure and individual tree growth. The Gascoyne region of Western Australia provides a unique opportunity to investigate whether mangroves growing within an inland semi-arid environment display similar growth patterns and ecophysiological responses to their coastal counterparts.

This …

Persons As Plants: Ecopsychology And The Return To The Dream Of Nature, Monica Gagliano

Landscapes: the Journal of the International Centre for Landscape and Language

Abstract. In this article, I examine human-plant perceptions and interactions in terms of developing a new perspective on the perception and the actions of people towards plants. By combining my scientific understanding of the biological world and my own experiences working with plant shamans, storytellers and mystics from around the world, I engage with the idea that the hierarchical structure by which Western science defines the variety of life forms as ‘primitive’ or ‘more evolved’ is at the root of the current environmental crisis and I argue that the solution to it rests in a change of this very perspective.

Threats And Knowledge Gaps For Ecosystem Services Provided By Kelp Forests: A Northeast Atlantic Perspective, Dan A. Smale, Michael T. Burrows, Philippa J. Moore, Nessa O'Connor, Stephen J. Hawkins

Research outputs 2013

Kelp forests along temperate and polar coastlines represent some of most diverse and productive habitats on the Earth. Here, we synthesize information from >60 years of research on the structure and functioning of kelp forest habitats in European waters, with particular emphasis on the coasts of UK and Ireland, which represents an important biogeographic transition zone that is subjected to multiple threats and stressors. We collated existing data on kelp distribution and abundance and reanalyzed these data to describe the structure of kelp forests along a spatial gradient spanning more than 10° of latitude. We then examined ecological goods and …

Coastal Bacterioplankton Community Dynamics In Response To A Natural Disturbance, Sara K. Yeo, Megan J. Huggett, Alexander Eiler, Michael Rappe

Research outputs 2013

In order to characterize how disturbances to microbial communities are propagated over temporal and spatial scales in aquatic environments, the dynamics of bacterial assemblages throughout a subtropical coastal embayment were investigated via SSU rRNA gene analyses over an 8-month period, which encompassed a large storm event. During non-perturbed conditions, sampling sites clustered into three groups based on their microbial community composition: an offshore oceanic group, a freshwater group, and a distinct and persistent coastal group. Significant differences in measured environmental parameters or in the bacterial community due to the storm event were found only within the coastal cluster of sampling …

Applying The Principles Of Spatial Modelling To The Management Of Biodiversity In The Fragmented Landscapes Of South-Western Australia, Shaun Molloy

Theses: Doctorates and Masters

Biodiversity conservation throughout the world is challenged by the impacts of a changing climate on fragmented landscapes. To mitigate these threats, conservation managers require models which can demonstrate the consequences of both negative impacts and management actions. This need can be addressed through spatial modelling applications. Unfortunately, throughout much of the world, spatial modelling is forgone, being seen as requiring skills and resources beyond the means of many conservation planners and managers. This thesis seeks to address this dilemma by delivering criteria for a successful modelling application and by providing case studies which demonstrate how appropriate modelling can be undertaken …

The Biology And Ecology Of Epinephilidae Speciea And Their Implications To Fisheries Management, Jason R. How

Theses: Doctorates and Masters

This thesis examines the biological and ecological aspects of members of the globally exploited Epinephilidae with reference to fisheries management and in particular the use of closures. The leopard coralgrouper Plectropomus leopardus is a common reef fish throughout the Indo-Pacific region and a major target of both commercial and recreational fisheries. There has been limited research on this species in the eastern Indian Ocean, where there are only two populations. An examination of the species found a number of significant biological differences to their eastern Australian con-specifics. Most noticeable was the strong size-related cue over their protogynous sex change. The …