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Optimising recovery post-game or post-training could provide a competitive advantage to an athlete, especially if more than one bout of exercise is performed in a day. Active recovery is one common method that is thought to enhance the recovery process. Another recovery method that is gaining popularity is water immersion. The objective of this thesis was to analyse whether these two recovery methods provided greater recovery from explosive exercise than passive recovery. A physiological rationale that may explain the possibility of enhanced recovery with water immersion was initially investigated. The literature surrounding active recovery, water immersion and passive recovery on strength, cycling, running and jumping was then examined. Following these reviews an experimental study was conducted investigating the effects of water immersion, active recovery and passive recovery conducted after repeated bouts of explosive exercise. The rationale for active recovery post-exercise is that during intense exercise, fluid from the blood is forced into the working muscles due to the increase in mean arterial pressure, which increases muscle volume and decreases blood plasma fraction. Active recovery reduces this exercise induced edema and, with an associated increase in blood flow throughout the body, may increase the metabolism of waste substrates produced during exercise. Researchers have observed this increased substrate metabolism with reductions in post-exercise blood lactate accumulation following active recovery. Water immersion would appear to cause a similar physiological response to active recovery without the need to expend extra energy. When a large portion of the body is immersed, hydrostatic pressure acts on the body's fluids within the immersed region. Fluids from the extravascular space move into the vascular system reducing exercise-induced increases in muscular volume and reducing soft tissue inflammation. Additionally, blood volume increases and is redistributed towards the central cavity, which in turn increases cardiac preload, stroke volume, cardiac output, and blood flow throughout the body. Cardiac output increases in relation to the depth of immersion and have been observed to increase by as much as 102% during head-out immersions. These cardiovascular responses occur without any increase in energy expenditure. If extra-intravascular fluid movement is enhanced, then the movement and metabolism of waste substrates could increase. Observations of increased post-exercise blood lactate clearance with water immersion would support this theory. Most methodologies studying the performance benefits of active recovery and water immersion suffer many limitations. These limitations often consist of the experimental time schedule not replicating what is likely to occur in a practical situation, no isolation of water temperature and hydrostatic pressure effects, and lack of a sport-like exercise consisting of repeated expressions of explosive power. Light-intensity active recovery and water immersion do not appear to be detrimental to performance, but neither does there appear to be enough evidence to claim they are beneficial. Effects of active recovery and water immersion would seem to be trivial to small, with any benefits more likely following multiple bouts of high-intensity exercise and recovery or following muscle damaging exercise. There may be a link between blood plasma fraction and performance, however, evidence is inconclusive. Given these issues and limitations the aim of this research was to investigate whether combinations of active recovery, water immersion and passive recovery could maintain peak power and work during subsequent bouts of explosive exercise. We also investigated whether there was any difference in subjects' blood plasma faction and perceived fatigue between the recovery modes. A cross-over experiment was conducted on seven subjects over four weeks. On the same day of each week subjects performed three sessions of maximal jumping, each two hours apart, followed by a different recovery method. Each jump session consisted of three sets of 20 maximal jumps repeated every three seconds, with a minute's rest in-between. Immediately following the jumping subjects performed 10 minutes of either (A) active recovery on a cycle ergometer followed by seated rest, (I) immersion to the gluteal fold in 19°C water followed by seated rest, (AI) active recovery followed by immersion, or (P) seated passive rest. Jumping was conducted on an instrumented supine squat machine that allowed the measurement of total peak power and total work. Pre-jump, post jump and post-recovery blood was taken and the percentage of blood plasma fraction calculated. Perceived leg fatigue was also measured at these times. Observed differences in total peak power and total work between the recovery modes were non-significant. No differences were observed in the change of blood plasma fraction between the recovery modes or perceived fatigue. One reason for any lack of difference between the recovery modes may have been the brevity of the recovery time. Research that has observed significant benefits of active recovery and water immersion compared to passive recovery have used recovery times greater of 15 minutes or more. Additionally, changes in blood plasma fraction between active recovery, water immersion and passive recovery have not been apparent until at least 10 minutes post-recovery in previous research. Alternatively, rather than brevity, it may be that active recovery or water immersion simply does not provide any benefit to performance recovery. Overall there is a meagre amount of research into active recovery, water immersion and passive recovery. Further research that incorporates a variety of exercise and recovery protocols is required.

A series of physical and chemical analyses were conducted over a fifteen month period to establish the ecological risk, if any, of discharging minewater into aquatic ecosystems. Organic and inorganic analyses were used to determine the extent of contamination of minewater with soluble hydraulic fluids and other contaminant species. Throughout the sampling period the pithead discharge water exhibited a neutral pH and low levels of iron, manganese, zinc and potassium were found. Parallel toxicological and chemical studies identified elevated zinc levels above published toxicity levels for the test species Ceriodaphnia Dubia, but were not confirmed by subsequent study. The presence of organic species in the pit head discharge water was also identified, but the levels were found to be quite variable. Treatment processes involving the detention of the surface minewater and subsequent passage through wetlands exhibited a beneficial effect in reducing pollutant levels prior to disposal. Comparisons of the chemical composition of the minewater discharge with those of local waters were carried out and found to be similar in nature. / Master of Science (Hons)

The aim of this work was to develop devices for elite athletes to record performance related parameters during their training. A device was initially designed and built for rowing to record the motion of the boat. This was to gain understanding of motion signals in a one dimensional plane. The device uses a iPAQ handheld computer for recording and display of data to the user. Using the knowledge obtained from the accelerometer data of the rowing system an initial prototype device was designed and constructed for use in swimming. This device was required to be wearable whilst the swimmer was training, thus it had to record the data onboard. A second version of the swimming device was constructed to improve the usability of the device. The swimming device has fully sealed electronics, wireless charging and infrared communications. The device records three dimensional acceleration patterns at 150Hz, and can store over 6 hours of data using the internal memory. The device can operate for greater than 12 hours before needing to be recharged. The data collected from the swimming device was used to develop processing algorithms to extract when the swimmers push off from the wall, the type of stroke they are swimming, and for freestyle the stroke count. The results of the wall push off algorithm were compared against manual hand timing with 90% algorithm results being with ±1 second of the hand timing data. The stroke type identification algorithm determines which stroke is being swum and presently has an accuracy of 95%. The results of the freestyle stroke count algorithm were compared against manual stroke counts from raw accelerometers data and underwater video. Of the 164 data sets analysed over 90% of the algorithm results were within ±1 strokes of the manual recorded stroke counts.

This study has contributed to the development of the reference condition approach in disturbed landscapes. The reference condition approach has been an important development for the bioassessment of aquatic ecosystems by providing a practical tool for the accurate assessment of river condition. The selection of appropriate reference sites is critical to the success of the predictive model in terms of being able to distinguish between natural variation in biota and the effects of human disturbance. Capturing natural variability and explaining it is a key difference between the reference condition approach and other study designs (e.g. before/after/control/impact). Natural disturbances such as drought or bushfire can significantly alter the ecological condition of streams, and although the ecological condition of streams affected by natural drought or bushfire is part of the natural cycle, this natural variation of the ecological condition is rarely incorporated into many study designs because of a mismatch in time scales. Human disturbance has also significantly altered the condition of landscapes through the development of agriculture and urbanisation. In urban or agricultural landscapes it can be impossible to locate streams that have not been modified by human activity for use as a reference condition. This study looked at the effects of natural disturbance on the reference condition, in terms of the way natural disturbance affects the prediction of stream condition and also the incorporation of the condition of streams experiencing natural disturbance into a predictive model. Additionally this study identified an alternative benchmark for modified landscapes based on the presence of good management practices for river protection, and tested this benchmark for the assessment of streams impacted by urbanisation. Drought and bushfire regularly disturb aquatic ecosystems in Australia, and affected reference sites in the ACT and South Coast region of New South Wales in 2002 and 2003. Drought and bushfire conditions affected macroinvertebrates and environmental variables across these streams, and the majority of sites were assessed as significantly impaired using regional AUSRIVAS (AUstralian RIVers Assessment System) models. This indicated the existing reference conditions for these regions had not incorporated the ecological conditions of reference sites suffering these natural disturbances. Many of the environmental variables used to predict the condition of streams were also affected by drought or bushfire. The changes to environmental variables affected how sites were assessed in models, but the overall assessment was not significantly changed from the initial assessment that drought or bushfire had significantly impaired the ecological condition. To reduce potential assessment errors associated with changes to predictor variables an attempt was made to construct new models with changeable variables excluded. However, it was not possible to completely exclude these types of variables, and subsequent models were no better than the original models in terms of changes to predictor variables affecting the generation of expected taxa lists. The changes to environmental variables did not affect the actual assessment of site condition because although group membership probabilities were changed the probabilities of taxon occurrence did not change significantly. The different reference site groups all contained some common taxa that occurred at most sites and even when group probabilities changed this did not change the probability of these taxa occurring at a test site. For regional models, such as the ACT or NSW South Coast, changes to predictor variables may not significantly affect the assessment of site condition. Incorporating reference sites under drought conditions into a predictive model was an effective way of discriminating the effects of drought from human disturbance. The model only provided two different ecological conditions, a single drought measurement and a single non-drought measurement, so the model did not fully encompass the potential natural variability. The model has value as a starting point and was effective in distinguishing sites affected by human disturbance from sites affected by drought. Good Management Practice (GMP) for river protection is any intervention that minimises human impact on stream condition. Urban sites protected by GMP were used as an alternative benchmark to a minimally impacted reference condition. The criteria used to select reference sites were not sufficiently robust to detect a significant benefit of GMP on physical or chemical characteristics of protected sites, compared to sites without GMP. In general however, the physical and chemical condition of GMP sites was better than sites without GMP and there were significant differences in macroinvertebrate assemblages of GMP and non-GMP sites. A refinement to the site selection process is proposed to include a specific assessment of GMP effectiveness for the protection it is designed to provide. This will substantially improve the robustness of a GMP benchmark and provide a clearer picture of the factors controlling biota in urban streams protected by GMP. The GMP benchmark was developed into a predictive model for the assessment of urban stream health, and in terms of the assessment of test site condition, it did not differ significantly from a model using minimally impacted sites. The purpose of the GMP benchmark was to provide an alternative reference condition for the assessment of stream health in modified landscapes when minimally impacted sites are unavailable or provide an unattainable benchmark. The GMP reference condition as an alternative can provide an attainable and realistic benchmark. The development and application of the suggested site selection protocol will improve the robustness of the GMP benchmark and better account for natural variation in the biota and physical characteristics of the sites used to determine the reference condition.

Estuarine benthic assemblages are often numerically dominated by polychaetes. The limits of these populations are determined by larval, and probably to a lesser extent adult movement. A previous study (Newton 1996), indicated that planktonic polychaete larvae were very abundant over the summer months in the Hopkins River; however, the identification and source of these larvae was not known. Defining the extent of a population, and therefore the likelihood of that population recovering following a perturbation, is crucial for effective estuarine management. This study investigated both the likely source of the larvae, (i.e. estuarine or marine) and the extent of larval dispersal within and between estuaries by addressing the following questions: Which taxa produced the planktonic larvae? Are these taxa resident estuarine species? Are the larvae of different taxa evenly distributed within the estuary or do physicochemical parameters or other factors influence their abundance? Are the same larvae found in other estuaries along the coast? and Is there exchange of these larval taxa with the marine environment and other estuaries? Larvae were identified and described by culturing commonly occurring planktonic larvae until adult characteristics appeared. The spionids, Carazziella victoriensis and Prionospio Tatura, numerically dominated the plankton in the Hopkins and the spionid, Orthoprionospio cirriformia was recorded from the Hopkins, Curdies and Gellibrand estuaries. Two spionids, Carazziella sp. and Polydora sp. were identified from tidal waters. Mouth status and physicochemical conditions (salinity, temperature and dissolved oxygen) were monitored in each estuary. Whereas the Merri and Gellibrand estuaries were predominantly stratified over the sampling period, the Curdies was more often well mixed and the Hopkins varied from well mixed to stratified. The duration of mouth opening and hence the opportunity for larval exchange also varied in each estuary. The Merri River was closed for 13.5% of days over the study period, the Gellibrand River for 18.4%, the Hopkins River for 49% and the Curdies River for 71.0%. The distributions of larvae at spatial scales of metres, 100s of metres and kilometres were investigated within a single estuary. While the same larvae, C. victoriensis, P. Tatura and bivalve larvae, were found along the length of the Hopkins estuary the abundances varied at different spatial scales suggesting different processes were influencing the distribution of P. Tatura larvae, and C. victoriensis and bivalve larvae. The distribution of larvae between several estuaries was investigated by monitoring meroplankton at two sites at the mouth of each of the four estuaries approximately monthly (except for winter months). Different meroplanktonic assemblages were found to distinguish each estuary. Further, C. victoriensis and P. Tatura larvae were only recorded in the Hopkins but larvae of the spionid, Orthoprionopio cirriformia were detected in the Hopkins, Curdies and Gellibrand estuaries. The extent of larval exchange with other estuaries and the marine environment was determined by monitoring tidal waters. Settlement trays were also deployed to determine if larvae were moving into estuaries and settling but not recruiting. P. tatura larvae were not detected in the tidal waters of any estuary and while C. victoriensis and O. cirriformia were found in both flood and ebb tides there was no evidence of movement of theses taxa to other estuaries. Larvae of the spionids, Carazziella sp. and Polydora sp., were found in tidal waters of each estuary but were rarely detected in the plankton within the estuaries. Neither species was found as an adult in background cores from any estuary, nor with the exception of a few individuals in the Merri, were they detected in settlement trays in any estuary. I conclude that the source of the larvae of C. victoriensis, P. Tatura and O. cirriformia is estuarine and while C. victoriensis, and O. cirriformia move in and outh of the source estuary in tidal waters there was no evidence for movement to other estuaries. The spionids, Carazziella sp. and Polydora sp were considered to be marine and while they moved in and out of estuaries in tidal waters they did not usually settle in the estuaries. The results of this study are a crucial first step in the development of ecological models to better understand dispersal in seasonally closed estuaries that are typical of southern Australia. This study emphasises the unique physicochemical characteristics and biological assemblages within these estuaries and the need for estuarine management to reflect these differences.

"March 2004" / Bibliography: leaves 115-141. / 141. [8] leaves : ill., maps, photos (col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Localised disturbance can generate considerable patchiness in the structure and composition of subtidal habitats which is a key determinant of differences in the diversity of associated assemblages of invertebrates. / Thesis (Ph.D.)--University of Adelaide, School of Earth and Environmental Sciences, Discipline of Environmental Biology, 2004

<p>Human activities have caused acidification of freshwater systems on a large scale resulting in reduced species diversity and ecological functioning in many lakes and streams. However, many naturally acidic freshwater systems have also been found, for instance in northern Sweden. In regions where such naturally acidic aquatic ecosystems have prevailed over evolutionary periods, species diversity and ecological functioning are not automatically impaired due to possible adaptation to the putatively adverse environmental conditions. I studied species diversity patterns and ecological functioning in anthropogenically acidified, naturally acidic, circumneutral, and limed streams to test the adaptation hypothesis and examine the ecological effects of variation in naturally acidic water chemistry. Species diversity was studied using benthic macroinvertebrates, while functioning was modelled using the decomposition rates of leaf litter. In accordance with the evolutionary species pool hypothesis, species richness was reduced more strongly in regions with anthropogenic than natural acidity when compared to circumneutral streams, supporting the adaptation hypothesis. In contrast, the patterns in ecological functioning along the pH-gradients did not differ between regions with anthropogenic and natural acidity, likely resulting from compensation: the biomass of tolerant taxa probably increased which thus rescued the loss in functioning otherwise mediated by the more sensitive taxa. Furthermore, the naturally variable acidic water chemistry clearly supported distinct macroinvertebrate assemblages, as was reflected in differing patterns of species diversity and ecological functioning. Such naturally acidic waters that were rich in dissolved organic carbon supported higher ecosystem process rates and lower species diversity than waters that contained little dissolved organic carbon. Upon liming naturally acidic streams microbial leaf decomposition increased, whereas shredding decreased along with changes in shredder abundances. The abundance of large caddisflies decreased, while the abundance of small stoneflies increased. The results suggest that various types of benthic macroinvertebrates with varying levels of adaptation and tolerance inhabited the hydrochemically variable naturally acidic streams. The distributions of macroinvertebrates in response to different pH levels and differences in acid quality and how these distributions translate into varying patterns of species diversity and ecological functioning are worthy of further investigation. This will likely improve our understanding of how such naturally acidic streams and their biota can be successfully managed.</p>

<p>In the spring of 2007 the Kuba Dam in Nätra Stream was removed for restoration purposes, mainly to give free passage to migrating fish. This action gave an opportunity to study the effects of dam removal on organisms both on land and in water, a type of study which is in demand for planning purposes of future dam removals. This study focuses on the effects upon the vegetation along the stream where the former reservoir was situated. Willow cuttings and sunflower seeds were used as phytometers to assess the growth conditions one year after removal at three different elevation levels at four different sites along the Nätra Stream. The reaches studied were the former reservoir of Kuba Dam (Site A), the area just downstream of this former dam (Site B), further upstream in the reservoir of the existing Nyfors Dam (Site C), and even further upstream at Myreforsen, a reference area not affected by dams (Site D). Willow cuttings and sunflower seeds were planted at three different riparian levels at the sites in June and left to grow until August when growth results were collected. Many of the cuttings had died but statistically significant differences between sites could still be detected. They showed that the former reservoir shorelines in Kuba (Site A) had a plant growth significantly higher than the other regulated site. In other words, it was no longer equal to an existing reservoir but not yet similar to a free-flowing reach. The western side of the stream at this site had a higher growth than the eastern side and also higher than all the other sites. As for the three levels, the results showed a higher growth at the lowest elevation level at site A than all at the other levels and sites. This suggests that a combination of good access to sunlight and nutrients and fine-grade moist substrate results in a good growing conditions nearer the water in this former reservoir. The results for the sunflower seeds showed that the reference reach had a higher colonization success than the other sites.</p> / <p>Utrivningen av Kubadammen i Nätraån våren 2007 gav möjlighet att studera och följa upp hur en sådan förändring påverkar organismer på land och i vatten både uppströms och nedströms den tidigare dammen. Denna typ av undersökningar efterfrågas allt mer i och med att fler och fler dammar rivs av olika anledningar. I Kubadammens fall hade dammen förlorat sin ursprungliga roll och de fördelar som magasinet förde med sig för bland annat rekreation vägde inte längre upp dämningens negativa effekter på vattendragets ekosystem, till exempel som vandringshinder för fiskar. I denna studie har fokus lagts på vad som sker med vegetationen på stränderna längs det forna vattenmagasinet efter rivning. Med hjälp av videkvistar och solrosfrön som fytometrar undersöktes tillväxten ett år efter rivning på tre olika strandnivåer på fyra olika lokaler längs Nätraån. Dessa lokaler var Kubadammens gamla magasin (Lokal A), området direkt nedströms den före detta dammen (Lokal B), den nuvarande Nyforsdammens magasin (Lokal C) uppströms den före detta dammen, samt en referenssträcka vid Myreforsen (Lokal D) uppströms alla Nätraåns dammar och därmed ej påverkad av dämningseffekter. Videkvistarna och solrosorna planterades på tre nivåer på de olika lokalerna i juni och tilläts växa till augusti då tillväxtresultaten samlades in. Många kvistar hade dött under tiden men tillräckligt många överlevde för att det skulle gå att läsa ut statistiskt signifikanta skillnader i tillväxt. Resultaten visade att det före detta magasinet vid Kuba (Lokal A) hade en signifikant högre tillväxt än de andra lokalerna, vilket visar på att tillväxtförhållandena för vide varken liknar dem i ett befintligt magasin eller på en orörd sträcka eller nedströmssträckan, utan var betydligt mer gynnsamma. På denna lokal växte fytometrarna dessutom signifikant bättre på den västra sidan än på den östra sidan. När man ser till de tre nivåerna så växte videkvistarna i nivån närmast vattnet i det före detta magasinet vid Kuba bättre än på de övriga nivåerna på samma lokal och på de övriga lokalerna. Troligtvis beror detta på en kombination av öppenhet som ger bra tillgång till solljus, bra näringstillgång, substratets finkornighet och förmåga att hålla kvar fukt närmare vattnet. Resultaten av solrosfrönas etablering visade på att referenssträckan hade en högre etablering än övriga lokaler.</p>

<p>Although there is much theoretical and empirical data about the life history responses of time constrained organisms, little is known about the latitude compensating mechanism that enables northern populations’ developmental rates to compensate for latitude. To investigate the importance of photoperiod on development and growth, I collected adults and raised the offspring of the obligatory univoltine damselfly Lestes sponsa from two populations at different latitudes (53º N and 63º N). The offspring were raised in a common laboratory environment at 21º C and at the two photoperiods corresponding to the sites of collection. Field data showed that adult and egg sizes decreased towards the higher latitude. This adult size difference was a genetically fixed trait since the same size difference between populations was also found when larvae where reared in the laboratory. All studied individuals expressed shorter development time and faster growth rates under northern photoperiod regimes. Northern damselflies showed fixed body size and mass at emergence despite being reared at different photoperiod conditions. Similarly, southern individuals kept body size at emergence constant at both photoregimes, but overcompensated shorter development time in the northern photoregime by gaining higher body mass than in original,southern photoregime. There was no difference in hatching synchronisation between larvae from the south and the north. I found evidence of higher synchrony at adult emergence among northern individuals. The previous investigation of L. sponsa phenology in natural conditions together with these laboratory results indicate the presence of the latitude compensating mechanism that is triggered by a response to photoperiod. A positive correlation between photoperiod and developmental rate in this damselfly, and probably in many other temperate insect species, might be adaptive since it optimises the life history stage transitions and body size/mass at each latitude.</p>