<p>The aim of the study is to understand the level of co-operation between emerging and commercial farmers in a Water User Associations. The effort is expected to inform policy and improve practice in the building of new water institutions as government strives to implement IWRM.</p>

High latitude soils are estimated to store a considerable part of the global pool of soil organic carbon (SOC). Studies of global and regional SOC pools have estimated total inventories in northern Sweden’s subarctic region to fall within 10-50 kg m-2. However, correction factors for stone and boulder content of soils are often overlooked in SOC-studies and soil profiles are commonly normalized to a depth of 1 m, which can result in substantial overestimates of the SOC pool if a large part of the soil volume is occupied by stones/boulders or if the soil depth is shallower than 1 m. This study was performed to quantify SOC in soils of the Torneträsk catchment area using detailed measures of soil depth and stone/boulder contents. Two non-destructive sampling methods, ground penetrating radar (GPR) and rod penetration, were used to measure soil depth and stone and boulder content in the catchment area. Results show that average soil depth (n = 52344) varied between 0.95 – 2.14 m depending on elevation and the average mire depth was 0.63 m. Stone and boulder content of the soil was estimated to 49 – 68 % depending on elevation. The results were added to existing carbon and soil density data from the Torneträsk catchment area and total SOC inventories were calculated to 6.8 – 13.1 kg m-2. The results of this study indicate that previous studies on regional and global scale may have overestimated the SOC pools in the subarctic regions of northern Sweden.

Water governance worldwide is going through a shift towards more holistic and participatory approaches. In Europe, the EU Water Framework Directive (WFD) adopted in 2000, aims at protecting surface water and groundwater. The WFD emphasizes the importance of stakeholder participation in planning and implementation of the directive, and in order to reach environmental objectives. However, the empirical findings are insufficient regarding how stakeholder participation can lead to improved decisions and implemented plans. In Sweden, a major water quality problem is eutrophication caused to a large extend by diffuse nutrient leakage from agriculture. Therefore, it is important to involve farmers in water management, since their participation can lead the commitment of mitigation measures for reduced nutrient leakage. The overall aim of this study is to contribute the knowledge and understanding of active stakeholder participation in water management, in particular how it can lead to implementation of water quality objectives. The thesis addresses stakeholder participation in eutrophication management in local Swedish catchments, with a particular focus on farmers’ participation in the commitment of mitigation measures. The results are based on case study research, involving four catchment areas in Sweden with severe eutrophication problems. The thesis identified socio-demographic factors, farmers’ knowledge, and the level of existing information and economic support for wetland creation, as factors affecting farmers’ willingness to participate in wetland creation to mitigate nutrient leakage. In the local catchment groups studied, farmers and other local stakeholders participated to discuss potential mitigation activities. In these, farmers emphasized other emitting actors’ responsibility and commitment in local action plans. Where this was realized, social capital within the group increased and led to further collaboration. The thesis also analyzed large-scale wetland programmes at catchment scale, where the organizational and institutional arrangements were central to realize farmers’ participation: inter-municipal agreements entailed sufficient resources, the organization involved the most relevant actors; and leadership resources were important. The thesis argues that organizing water management at a catchment level can be important to cope with challenges related to stake-holder participation for mitigating diffuse nutrient leakage. In particular for dissemination and collection of information, suggesting potential measures for all concerned actors, provide resources needed to realize actions, and to build trust and collaboration. The thesis also emphasized that stakeholder participation has to be underpinned by a genuine meaning, both for the initiators and the participants. / <p>QC 20150506</p>

With the increasing degradation of rivers worldwide, an understanding of spatial and temporal patterns in freshwater quality is important. Water quality is highly variable in space and time, yet this is largely overlooked at the scale of stream catchments. I employed a landscape ecology approach to examine the spatial patterning of water quality in complex, impacted stream networks on the Canterbury Plains of the South Island of New Zealand, with the goal of understanding how land-use effects proliferate through stream systems. In particular, I used “snapshot” sampling events in conjunction with spatial modelling and longitudinal profiles to investigate the ways in which spatial and environmental factors influence the variability of water quality in stream networks. Spatial eigenfunction analyses showed that distance measures, which took into account variable connectivity by flow and distance along the stream between sites, explained more spatial variance in water quality than traditional distance metrics. Small upstream reaches were more spatially and temporally variable than main stems (under summer base-flow conditions). The extent of spatial variation in water quality differed between stream networks, potentially depending on linkages to groundwater and the surrounding landscape. My results indicated that the water quality of headwater streams can have a disproportionate influence over water quality throughout an entire network. I investigated spatio-temporal patterns in water quality more intensively in one stream network, the Cam River, in which I found consistent spatial pattern through time. The relative balance between nutrient inputs (pollution and groundwater) and in-stream conditions influenced the spatial pattern of water quality, as well as that of several ecosystem processes which I measured simultaneously. The spatially intensive and explicit approach has allowed identification of key factors controlling water quality and ecosystem processes throughout the Cam River. This research highlights the importance of taking a spatially explicit approach when studying stream water quality and that such an approach could be insightful and will contribute to solving current stream management problems.

There has been a dramatic expansion of dairying in New Zealand in the last two decades. This has been accompanied by a series of environmental issues around water use and water pollution. This thesis looks at the issue of excess nitrogen and phosphorus lost off dairy farms to waterways using a mixed method approach. Qualitative interviews with dairy farmers and GIS based water quality modelling are employed to explore whether the introduction of nutrient benchmarks would achieve sustainable milk production systems. Two Best Practice Dairy Catchments, Waikakahi in South Canterbury and Inchbonnie on the West Coast, were investigated as the study areas. These catchments are part of an established DairyNZ program. Findings show that nutrient benchmarks do have the ability to achieve sustainable milk production systems in the catchments. It presents the implications and recommendations for the benchmarking project.

Farming practices within the upper Selwyn plains have significantly expanded, and are becoming more dependent on groundwater as a reliable source of irrigation. This expansion has resulted in the rapid development of the groundwater resource and water levels in many wells have reached record low levels. Groundwater resources can be found within at least three aquifers within the glacial gravel deposits of the upper Selwyn plains. Aquifer 1 occurs between approximately 0-30 m, aquifer 2 between 40-85 m and aquifer 3 greater than 100 m below the surface. Aquifers 1 and 2 occur within close proximity to the Selwyn River and its tributaries. Aquifer 1 is unconfined, aquifer 2 semi-confined and aquifer 3 semi-confined to confined. Significant leakage of groundwater occurs between the different aquifers. Recharge sources to the aquifers include rainfall infiltration and river seepage. Water levels and groundwater chemistry suggest that the Selwyn River provides the dominant source of recharge to aquifers 1 and 2 in areas immediately surrounding the river and to the south of the current course of the river between Greendale and Dunsandel.

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The Bells Creek catchment covers an area of 100 km2 in the northern part of the Pumicestone Passage region of southeast Queensland. This catchment is an example of a low-lying sub-tropical coastal plain including both freshwater and estuarine settings. The main creeks drain into Pumicestone Passage, a large shallow estuary, which is a declared marine habitat and a Ramsar listed wading bird location. The Bells Creek catchment has undergone land-use change from bushland to grazing to pine plantations and is now coming under pressure for urban development. Quaternary age unconsolidated sediments are the dominant surface material in this area and formed during the last marine transgression. Of significance for such a setting is that estuarine sediments can retain metals mobilised as a result of natural processes (e.g. weathering) and anthropogenic activities (e.g. land-use disturbance). As trace metals can also occur naturally in rocks and their weathered products, it is of value to clearly distinguish natural and anthropogenic controls over metal source, distribution and mobility. To achieve this aim two approaches were taken: 1) to determine the factors controlling the geochemistry of weathered profiles, unconsolidated sediments, soils and natural waters, and 2) to identify the most effective analytical and numerical methods for evaluating metal concentration in different solid materials. This investigation is structured around four linked papers. The influence of mineralogy, geological setting, location of water table and depth of burial on the geochemistry of weathered profile are assessed in Paper 1. The second paper is an investigation of different analytical approaches for studying weathered sedimentary rocks, as well as the testing of several numerical methods for evaluating geochemical data from weathered profiles. In paper 3, a large heterogeneous geochemical data set including trace metals, total organic carbon and sulfur content, in addition to mineralogy and land use practices are integrated to enable evaluation of geochemical and anthropogenic processes controlling metal distribution. The fourth paper considers the distribution of iron and its transport as well as variations in size and morphology of different forms of framboidal pyrite within a smaller sub-catchment in the southern part of the study area. The labile and heterogeneous nature of the bedrock of the region, the Landsborough Sandstone, along with the sub-tropical climate of the area have resulted in weathering profiles up to 26 m deep. Due to the absence of industrial activity in the Bells Creek catchment, such weathering of the bedrock constitutes the major process governing metal distribution throughout the area. Analysis by X-ray diffraction (XRD) shows that the primary minerals occurring in the weathered profiles are quartz, plagioclase and K-feldspars while kaolinite is the most dominant secondary mineral present. Overall, parent rock silicates have been extensively replaced by clay minerals and Fe oxides. The relative influence of mineralogy, geological setting and groundwater over chemical weathering and geochemical cycling of metals can be summarised as follows: Mineralogy>geological setting>watertable position>depth of profile burial As the relationship between the total metal composition and the extractable and mobile component has environmental significance, a comparison was made between these forms of metals in weathered material. This comparison shows that metals such as V, Cr and Fe are part of the aluminosilicate matrix and remain largely in primary mineral structures. The retention of these metals may lead to their future release to the environment during on-going weathering. Other elements such as Cu, Zn, Pb, however, are found to be primarily adsorbed to sediment particles and therefore, easily releasable to the environment. As limited information on weathering of sedimentary rocks is reported in the literature, a variety of chemical analysis and numerical assessment methods were used to understand the geochemical processes involved in trace metal mobility in the weathered profiles. Two analytical methods of digestion, hydrofluoric acid and x-ray fluorescence were tested and found to be highly comparable except for refractory elements such as V and Cr. Among the numerical methods applied to the dataset were "chemical and mineralogical indices", "weight loss factor" and "immobile element approach". The "immobile element approach" was found to be the most appropriate method to characterise the weathering profiles typical of the catchment. This method considers a weathering system to be open and transforms the absolute values of trace metals enabling a quantitative evaluation of metal mobility. The following sequence of mobility was determined after applying this method to the data generated in this study: Zn>Pb>Cu>Cr>V The above sequence of mobility is supported by the comparison between extractable and total metal concentrations where Cr and V were identified as being part of aluminosilicate matrix and less mobile. On the other hand, Zn, Pb and Cu were found to exist in adsorbed form and to be readily released to the environment. Trace elements released through weathering and erosion of the bedrock can accumulate in estuarine and coastal sediments. Therefore, both the lateral and vertical distribution of trace metals within sediments and soils of Bells Creek catchment were investigated. Natural and anthropogenic factors controlling metal distribution were compared and it was concluded that the natural sediment character such as its mineral content is more significant than anthropogenic influences in controlling lateral and vertical metal distribution. Further, due to varying degrees of weathering and the heterogeneous nature of soils and sediments, the data were normalised. After testing several methods, it was concluded that calculation of an enrichment factor was the most appropriate. The enrichment factor revealed that elevated trace metal concentrations at some sites are due to bedrock weathering. Due to the environmental persistence of iron, excess of this common metal has always been of environmental concern in many coastal settings. In the small Halls Creek sub-catchment, for example, iron anomalies were detected in bottom sediments (Fe up to 14%). This finding has significance in the area, as iron has been identified as one of the major contributors in the growth of the toxic cyanobacteria "Lyngbya majuscula" which can negatively impact on aquatic fauna. Iron concentrations were also shown to be high in natural stream waters of this coastal zone (up to 16 mg/L); in the bottom sediments of the creek, iron occurs as hematite (freshwater section) or pyrite (estuarine section). A variety of pyrite morphologies were identified in both bottom sediments and particulate matter samples including spherical closely packed framboids, and the rare form of euhedra which indicates slow crystallisation. The different components of this investigation have: 1) established the order and extent to which natural factors control weathering, 2) tested a number of analytical and numerical methods in evaluating weathering profiles, 3) assessed natural and anthropogenic factors and established the mobility sequence for trace metals in weathered profiles and, 4) determined the iron mineral speciation and established morphological variations of pyrite. As the area of Bells Creek catchment will be under development pressure in the future, findings of this study represent a baseline of comparison for environmental assessment and are of importance for environmental management.

The Tragowel Plains Irrigation District lies in the lower Loddon catchment of northern Victoria. Since the 1890s progressive development of the irrigation infrastructure of the Tragowel Plains has been accompanied by the development of irrigation induced soil salinity. In 1988 the State Government of Victoria supported the development of a community managed salinity management plan. At the same time, the water supply industry was significantly deregulated. Full cost recovery principles were applied to irrigation water pricing. Water entitlements were transformed into tradable commodities.The Tragowel Plains Salinity Plan was subsequently promoted by the Victorian government and the Loddon irrigation community as a model for encouraging structural change in a Commonwealth government facilitated regional development plan for the whole of the Loddon-Murray irrigation region. The process of developing this regional development plan revealed difference in the objectives of the various actors in this new planning process. The objective of community planners was the survival of the irrigation district. One of the objectives of Commonwealth was the transfer of water from low value use to high value use. These higher value uses were potentially elsewhere in the Murray Darling Basin. Further, these actors in the planning process used differing implicit models of the process of structural change in irrigation areas. The Commonwealth representatives had an implicit model of structural change in which farm consolidation was driven by the rate of exit from farming. They were also sceptical of the capacity of the Tragowel Plains salinity plan model to facilitate significant change in water use.

Thesis (Ph.D) -- University of Western Sydney, 2007. / A thesis submitted to the University of Western Sydney, College of Health and Science, School of Natural Sciences, in fulfilment of the requirements for the degree of Doctor of Philosophy. Includes bibliography.