This thesis examined the impact of anthropogenic alterations in four riverine catchments of the Eastern Mt. Lofty Ranges, South Australia, to identify if creek restoration via environmental flows is a viable management option and if so, to determine; 1) Whether an aquatic/riparian viable seed bank was present and if so what was its composition 2) The ecological condition of selected riverine reaches. This in combination with the seed bank study would identify those creeks that would most benefit from the imposition of environmental flows 3) The response of key species to the water regimes likely to result from the imposition of environmental flows 4) The influence of nutrient enrichment under a fluctuating water level and to use this information to formulate best practice policy for environmental flows 5) Whether aquatic plants promoted by environmental flows were a significant fraction of the diet for higher trophic levels represented by Trichopterans and Amphipods. The seed banks were of comparable density (ranging from 4,000 to 110,000 seeds m-2) and species richness (ranging from 13 to 20 aquatic / riparian species) to the seed banks of other Australian rivers and wetlands, but this varied significantly among riverine sections and across catchments. Out of a total of 81 species recorded, 51 were classified as terrestrial (63% of all species recorded). What is of greater concern was the number of exotic (both aquatic and terrestrial) species recorded: 43% of the species recorded in the Angas, 47% of the species in the Finniss, 39% of the species in Tookayerta creek and 43% of the species recorded in Currency creek were exotic, which are significantly higher in comparison to other Australian studies. There were 24 to 28 aquatic/riparian species recorded in the extant vegetation of each catchment that were not recorded in their seed banks. Likewise, a number of species (3 to 7) were recorded in each catchments seed bank that were not recorded in the extant vegetation of those catchments. A species of particular interest is Crassula sieberana, which is on the State endangered plant species list. Indices for assessing the ecological condition, health or integrity of a river or riparian habitat were employed to investigate the relationship between the river/riparian habitat and the land and water management practices associated with those habitats. Of the four catchments surveyed, each catchment identified a unique set of site parameters (subindex indicators) that were strongly correlated with its ecological condition. Indicator species analyses revealed pasture grasses to be a significant indicator of reaches in very poor condition (p = 0.0010) along the Finniss and Baumea juncea of those reaches in good condition (p = 0.0230). Along the Angas, Cotula coronopifolia was an indicator of those reaches in average condition (p = 0.0240) and along Currency creek, Cladium procerum was an indicator of those reaches in good condition (p = 0.0190). However, when all 115 surveyed reaches were analysed together, those reaches of average to excellent ecological condition were all strongly correlated (R2 = 0.50) with the subindex indicators: bank stability, % riparian cover, grazing, fenced, aquatic wood, and width of the riparian vegetation. This would indicate that these subindex indicators are the main site parameters determining the ecological condition of a riverine reach and hence its restoration potential. Those catchments or sub-catchments containing a high proportion of reaches classified to be in poor to very poor condition had significantly reduced seed banks. The influence of water level fluctuations (±15 cm, ±30 cm and ±45 cm) on the growth of four species of emergent macrophytes (Cyperus vaginatus, Phragmites australis, Typha domingensis and Triglochin procerum) were species dependent. These species naturally inhabits different zones across the elevation gradient. C. vaginatus, which has a high elevation preference, was strongly inhibited by increasing water depth and fluctuations in water levels. In contrast, species with an intermediate elevation preference, such as Phragmites australis and Typha domingensis, were more tolerant to both depth and water level fluctuations. However, the biomass and relative growth rate (RGR) of T. domingensis and P. australis were depressed when grown under the combination of deep elevation and a highly fluctuating water level (±45 cm). Between the static and ±45 cm amplitude treatments, growth of T. domingensis was inhibited by 52%. The growth of P. australis appeared to be enhanced by fluctuating water levels and only showed a severe drop-off in growth in the deep elevation, ±45 cm amplitude treatment. In C. vaginatus the RGR was dependent of the average emergent surface area (and the implied rate of carbon acquisition)(p<0.0001; r2=0.7196; F=87.276; n=36; RGR (mg g-1 day-1) = -5.096 + 4.313 × ln (Average emergent surface area (cm2)), but this was not the case in P. australis and T. domingensis (p>0.05) even when the photosynthetic canopy was partially inundated by rising water levels. Yet these two species demonstrated different growth rates when grown under different water regime amplitudes and at different elevations. Growth of T. procerum did not respond to either amplitude or elevation, but its RGR remained negative. This suggests that another factor(s) was limiting the growth of P. australis, T. domingensis and possibly T. procerum, a factor that varies with water level. Cyperus gymnocaulos had significantly increased plant performance (p <.0001) with increased nutrient loading rates but this effect was significantly reduced under a fluctuating water regime (p =0.0007). Remarkably, under a fluctuating regime, P. australis had a significant reduction in performance with increased nutrient loading rates (p =0.0013), whereas T. domingensis performance was significantly limited (p =0.034) even with increased nutrient loading rates. T. procerum too had increased plant performance with increased nutrient loading rates but this effect was reduced under a fluctuating regime. The morphological response by T. procerum demonstrates that it is mainly limited by the nutrient loading rates and not the water regime. However, it was significantly limited/reduced by its increased turnover rates caused by a stochastic fluctuating water regime. Illustrating that in fact the effects of nutrient enrichment on T. procerum were independent of water regime but bearing in mind that water regime is the primary factor determining the productivity of this species. For those species with higher elevation preferences, e.g. C. gymnocaulos, or low elevation preference, e.g. T. procerum, the effects of nutrient loading are independent of water regime, whereas those species with an intermediate elevation preference, e.g. P. australis and T. domingensis the effects of nutrient loading are largely dependent on the water regime. Amphipoda and Trichoptera selectively fed on succulent semi-emergent macrophytes across sites of average to excellent ecological condition (31-64% to 65-97% of diet), depending on availability. These semi-emergent macrophytes contained the lowest C:N ratio (≈10:1), closest to that of their consumers (≈5:1) and therefore the highest nutritional content. In degraded riverine reaches, there were limited food resources available, hence course particulate organic matter (CPOM) formed the main dietary components of Amphipoda (20-53% of diet) even though it had the highest C:N ratio (≈40:1). At site VP. 1, filamentous algae was the main dietary component of Trichoptera (48-64% of diet) due to its availability and its low C:N ratio (≈14:1) in comparison to the other primary sources available. The imbalanced consumer-resource nutrient ratios in these degraded riverine reaches are likely to impose constraints on the growth and reproduction of their aquatic shredder communities with probable knock-on effects at higher trophic levels. The installation of environmental flows to restore and promote aquatic/riparian plant communities, which in turn would benefit higher trophic organisms, is a viable and realistic management option along selected reaches. Those selected reaches contain a significant aquatic/riparian seed bank and with sufficient physical habitat remaining to promote their germination and establishment. However, the imposition of environmental flows as a control measure to prevent the colonisation and dominance of particular species (T. domingensis and P. australis) was deemed to be redundant as a management technique given the limited water resources available. / Thesis (Ph.D.) -- School of Earth and Environmental Sciences, 2007

The restoration of rivers and streams should be based on a strong conceptual framework. Streams are developing systems. As such, streams exhibit temporal behaviors that change with changing stream environments. Underlying the dynamic development of streams is potential capacity. Streams express this capacity as an array of habitats over time and across the landscape. Human land uses in the western United States have rapidly altered aquatic habitats as well as the processes that shape habitat. As a result, the diversity of native fishes and their habitats has been suppressed. Restoration is fundamentally about allowing stream systems to re-express their capacities. Four steps are provided to guide stream restoration activities. Key tasks include: identification of the historic patterns of habitat development; protection of the developmental diversity that remains; local application of specific knowledge about suppressive factors; classification of sensitive, critical or refugium habitats; release of anthropogenic suppression; and monitoring of biotic response to habitat change. Applying these concepts, I describe potential habitat refugia for aquatic organisms in the Joseph Creek basin in the Blue Mountains of northeast Oregon. Five valley segment classes, differing in valley corridor landforms, are described. Of these, low-gradient wide alluvial valleys have been most altered by human land use. Riparian vegetation has been extensively removed or altered in alluvial valleys. Currently, stream habitats are structurally depauperate, and warm to temperatures well above thermal tolerances of native salmonids. Potential refugia for native coldwater fishes in these valleys include patches of complex habitat within stream reaches. Reaches fenced to exclude domestic livestock exhibit narrower channels, more pools, and higher frequencies of stable vegetated banks than nearby unfenced reaches. During summer low flow periods, cold groundwater seeping into and accumulating in stream channels forms "cold pools". Cold pools provide potential seasonal refuge for coldwater fish at microhabitat scales. Cold pools are associated with channel complexity, and are more frequent in reaches with vigorous riparian vegetation. Seven classes of cold pools are described. Cold pool classes differ in minimum temperature, maximum depth and volume. Distributions of cold pool classes between valley segment classes suggest that valley geomorphology in addition to local channel form may influence development of certain cold pool types. Although refugia at the microhabitat to reach scales are important, the context within which remnant or refugium habitats and associated relict populations are maintained may ultimately determine the persistence of those species and habitats. In managed landscapes, protection and restoration of habitats at many scales may be necessary if we are to best insure the persistence of native species. / Graduation date: 1995

From the Proceedings of the 1972 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 5-6, 1972, Prescott, Arizona / Chaparral covers 4 million acres in Arizona. There is interest in determining how much these lands contribute to surface water supply, and how this contribution could be changed by conversion of chaparral cover to grass or grass forb. Results from treatment in the Whitespar watersheds are interpreted. Live oak and true mountain mahogany dominate the study area, which averages 22.7 inches of annual precipitation. Whitespar B watershed was converted to grasses in 1967, and litter was not disturbed. The 246 acre watershed produced more streamflow than the untreated, 303-acre control which tended to remain intermittent. Prior to treatment, streamflow in both watersheds was quite well synchronized. Watershed b has since had continual flow. Winter flows contribute about 77 percent of the increased streamflow volume. The degree of effect is still under study, but a new rainfall-runoff relationship for the treated watershed is necessitated.

From the Proceedings of the 1972 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 5-6, 1972, Prescott, Arizona / A critique of statistical properties of monthly flows on an ephemeral stream in Arizona is given. A subjective procedure, justified for managerial purposes not concerned with the variability of flow within the month, is proposed for sequential generation of monthly flow data. Ephemeral flows should be modeled by starting with at least historical daily flows for more meaningful monthly flow models. Stochastic properties of monthly streamflows and state transition probabilities are reviewed with regard to ephemeral streams. A flow chart for a streamflow model geared to digital computers, with a simulation of streamflow subroutine, is developed. Meaningful monthly flow models could serve as a check on alternative models (subjective matrix, lag-one auto regressive, harmonic, bivariate normal, bivariate log-normal models). Rules and guidelines are presented in developing meaningful probability matrices.

From the Proceedings of the 1973 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 4-5, 1973, Tucson, Arizona / An infiltration- wetting agent study, using the wetting agent "WATER-IN", was conducted in the ponderosa pine forest type of east central Arizona. An application rate of 10 gallons of wetting agent per acre was used on bare mineral soil and on ponderosa pine litter. The infiltration rate was measured by a modified North Fork infiltrometer. It was found that "WATER-IN" significantly increased water runoff when applied to litter, but, when applied to bare mineral soil, "WATER-IN" caused a significant increase in water infiltration. The wetting agent did not significantly affect antecedent moisture, soil particle distribution, litter water holding capacity, or litter bulk density. It is presently hypothesized that the increase in water infiltration on treated bare mineral soil is due to a decrease in the average bulk density of the surface inch of soil. The increase in runoff when litter is treated is probably due to an interaction, either physical, chemical, or both, between the humus layer and "WATER-IN ", creating a hydrophobic condition where one did not exist before.

From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / Effects of vegetation management on water and other renewable natural resources and amenities are subjects of a computerized reference retrieval information system operated out of the department of watershed management, university of Arizona. Although WaMIS (watershed management information system is a subsystem of the arid lands information system, it has its own unique scope. The system, which serves as a link between bibliographic material and users who need access to the information, provides a personalized bibliography for the user in his area of interest. Documents identified as relevant to the system's scope are abstracted and indexed, and references stored in a computer bank. In response to specific inquiries from users, the computer tapes are searched under indexing terms, author, and/or data, and a printout of citations (giving author, data, title, source, abstract, and indexing terms) relevant to the inquiry is sent to the user.

From the Proceedings of the 1975 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 11-12, 1975, Tempe, Arizona / Space-time variability in the hydrologic characteristics of four major soil series represented in the Silverbell validation site was investigated by sampling the infiltration characteristics, at randomly selected locations, under several vegetative covers within each series. The experimental data was the time distribution of infiltration which, for each sampled location, was fitted by least squares to the Philip's infiltration equation. The parameters of this equation have physical interpretation and therefore were used as measures of the infiltration characteristics. Analysis of variance was used to investigate the spatial variability in the parameters. The mean values of the parameters for selected soil-vegetation combinations were used to simulate runoff due to a rainfall event over a desert catchment "containing" the given combination. Statistical tests show that there is no significant difference among the infiltration parameters of all the soil-vegetation combinations. However, the statistically insignificant variations in the parameters produce significant variations in simulated runoff volumes indicating the sensitivity of the runoff generating process to infiltration characteristics vis-a-vis the hydrologic properties of the soils.

From the Proceedings of the 1975 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 11-12, 1975, Tempe, Arizona / Arizona's continued growth and development depends upon sound management of water resources, especially melted snow which is the primary source of water for the 1.1. Million residents of Maricopa county. The method for snowpack information gathering practiced by watershed specialists of the Salt River project in Arizona is described. The method is outlined, describing aircraft reconnaissance, direct enroute mapping of extent and depth of snowpack, and techniques for identifying ice and/or melt conditions. Under optimal conditions, this technique is considered more than acceptable for determining snowpack levels. Limitations of the technique result from the observer's tolerance of vertigo which can arise under flying conditions; cloud cover, which can reduce contrast and shadows thereby reducing accuracy of observation; and vegetation zones where density of plant matter screens much of the snow.

From the Proceedings of the 1976 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 29-May 1, 1976, Tucson, Arizona / The case study of an Upper San Pedro River watershed is developed to show how a multiple objective approach to decision-making may be used in watershed management. The effects of various land treatments and management practices on water runoff, sediment, recreation,, wildlife levels, and commercial potential of a study area are investigated while observing constraints' on available land and capital. The example involves the optimization of five objective functions subject to eighteen constraints. In an iterative manner, the decision-maker proceeds from one noninferior solution to another, comparing sets of land management activities for reaching specified goals, and evaluating trade-offs between individual objective functions. This technique, which involves the formulation of a surrogate objective function and the use of the cutting plane method to solve the general nonlinear problem, hopefully provides a compromise between oversimplified and computationally intractable approaches to multiobjective watershed management.

From the Proceedings of the 1977 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 15-16, 1977, Las Vegas, Nevada / Mathematical simulation of the erosion process is accomplished by using a time series of hydrologic parameters as inputs into a modified form of the Universal Soil Loss Equation. A parameter to account for antecedent moisture conditions was found to improve the predictive success of the Universal Soil Loss Equation. The simulation predicts sediment yield resulting from a stochastic sequence of precipitation events on an experimental watershed. This sediment model will be used as a component in a larger, more complex hydrologic simulation model which can be used to determine optimum reclamation practices for the strip mined areas of the arid Southwest. Data from regraded strip mine spoils at the Black Mesa of Arizona are used in calibrating the model.