Letteratura scientifica selezionata sul tema "Soils South Australia Barossa Valley"

This paper reports on an assessment of the need for early intervention services for children aged 0-8 years in the Southern Fleurieu sub-region of South Australia and an evaluation of the efficacy of utilising a generic community health service to provide the therapeutic and case management services to appropriately address those needs. Previous studies in regional South Australia estimated the incidence of developmental delay in children to be 5% of the total population aged 0-8 years (Barossa Valley, 1997). This estimate indicated a client group of over 130 in the Southern Fleurieu sub-region. The project team adopted a transdisciplinary model for early identification and intervention, with over half the children on the program aged less than five years, indicating that the program addressed needs of children at an early age. Outcomes have demonstrated the appropriateness of using a transdisciplinary approach in a regional setting and the community health service as the auspice has shown an increase in the capacity for therapists to provide the wide variety of programs that are essential in addressing early childhood delay.

Summary. A study of the petiole nutrient status of cvv. Shiraz, Cabernet Sauvignon and Rhine Riesling (Vitis vinifera) was carried out in 19 vineyards of each in the Barossa Valley, South Australia, during 1979 to 1982. The sampling unit chosen was the petiole of leaves opposite bunches, collected at flowering time. Nitrogen status (assessed as nitrate concentration) varied widely among vineyards and high concentrations of nitrate could be associated with use of organic materials (chicken litter, winery marc) in the vineyards. Phosphorus status was almost invariably higher than necessary. Potassium, magnesium and chloride status were usually high by Californian standards. Of the trace elements, boron was low in 1979 to 1980 in some vineyards, but sufficient in other years. Zinc and manganese were usually present in sufficient quantities. Daily sampling of petioles showed that nutrient levels during the flowering period changed less dramatically in this region than in California. Pre-bloom foliar sprays ofurea with zinc had non-significant effects on petiole nitrate concentration. Differences in nutrient concentrations between the three cultivars were detected in some years. The standards used to interpret petiole analysis data in California, while useful in the survey area, required some modification for local use, and working standards are proposed.

Morphological variation in Eucalyptus baxteri (Benth.) Maiden & Blakely ex Black is described throughout its range. There are two geographical forms, the principal differences between which are seedling morphology and the time of transition from juvenile to intermediate growth phase. The forms are hereby recognised as two species. E. baxteri s.str. has adult leaves broad near the apex, warty flower buds, often large fruits, and an early transition to intermediate foliage. It occurs in South Australia on Kangaroo Island, Fleurieu Peninsula, Barossa Range and near Wandilo, and in Victoria on the Grampian Ranges, Great Dividing Range and coastal areas, E. arenacea sp. nov. has tapering adult leaves, generally more slender, non-warty flower buds with longer, narrower pedicels and peduncles. Fruits are generally smaller with the disc less raised. Seedlings typically show a later transition to the intermediate foliage. It occurs on Mt Stapylton in the Grampian Ranges and the desert sand country of north-western Victoria and south-eastern South Australia. It is parapatric with E. baxteri on Kangaroo Island and Fleurieu Peninsula, and is restricted to sand deposits. A previous cladistic analysis suggested that E. baxteri s.l. is paraphyletic, E. arenacea sp. nov. being the sister taxon to E. baxteri s.str. and E. akina (an endemic of the Grampian Ranges). A sequence of evolutionary events is hypothesised by using the cladogram, the distribution of the taxa on different soils, and the geological history of the region.

The impact of elemental cycling and biological fractionation in the soil–vegetation system was investigated for 6 Red Brown Earth soil profiles (Xeralfs and Xerults) from South Australia by comparing geochemical and 87Sr/86Sr data from bulk soils, soil exchange pool, and vegetation (grapes). In all 6 soil profiles from 3 different sites, Ba/Ca ratios of vegetation, soil exchange pool, and bulk soils were found to be a more robust biological fractionation indicator than Sr/Ca ratios. In the base-poor soils of the Coonawarra–Padthaway area of South Australia, the degree of weathering of soil material, as estimated by titania and alumina contents, correlated very well with the biological fractionation indicator Ba/Ca. Soil horizons with greater clay and titania content also had higher degrees of biological fractionation. Similar Red Brown Earth soils 400 km north in the Clare Valley showed either no, or poor, biological fractionation signature in their bulk soil. The Clare Valley soils have a stronger colluvial component and are richer in base cations than the Coonawarra and Padthaway sites. The main source of bulk soil material in the base-poor soils of the Coonawarra–Padthaway areas is dust, which has greatly influenced the base cation concentration, Ba/Ca ratios, and the strontium isotope ratios. Soils from Clare Valley, by comparison, are less intensely weathered and are thus not as dependent on dust and biocycling for their base cations. Biological fractionation has not left a discernible signature on the composition of the bulk soil. The exchange pools at all 3 sites are dominated by wetfall–dryfall sources, which in this coastal area are dominated by marine sources. For the base-poor soils of the Coonawarra–Padthaway area, the most likely major source of aeolian detritus is Murray River mud. The fine-grained component of this mud, with its organic matter content, relatively high base cation concentrations, and low strontium isotope ratios (Douglas et al. 1995) appears to have overwhelmed other dust sources and caused a homogenisation of the geochemical signature of fine-grained bulk soils in this area. Subsequent in situ weathering and neoformation following dust deposition were strongly influenced by exchange phase concentrations and ratios and resulted in an enhanced biological fractionation signature of the soils.

Three senior Chief Executives of acute hospital trusts in the UK recently visited the Northern Territory (NT)and South Australia (SA) to study remote and rural health care in general - and Aboriginal health in particular. As with all other aspects of Aboriginal life, the subject of health status is highly charged and generates heightened emotions and intense political debate across the country but particularly in the NT and SA where many of the remote indigenous people live. Every "mainstream" Australian has an opinion on the trials and tribulations of the indigenous people.The field study was part of the NHS Leadership Centre's Senior Chief Executives' Development Programme. Itcomprised a longitudinal journey across the continent from Darwin (NT) through to Alice Springs to Tanundain the Barossa Valley and then on to Adelaide following the route of the 2,500 kilometre Stuart Highway. Itinvolved visiting rural health services, and meetings with Aboriginal leaders, academics, health practitioners and senior officials of the SA government.A specific research topic was to understand how practitioners working in extreme environments, and delivering long-term programmes of care, can maintain their morale and motivation.

A new approach to pedology was developed in Australia in the 1950's. It was based on geomorphic and stratigraphic principles and recognized the cyclic or episodic nature of soil and landscape development. The research reviewed here represents a contribution to that approach and further developments of it in fluvial erosional and depositional landscapes of south-eastern Australia and in glaciated landscapes of midwestern U.S.A. This research features detailed studies of hillslope layers and their relationship to alluvial valley fills; soil chronosequences on flights of alluvial terraces; the stratigraphy of coastal flood plains and the development of acid sulfate soils; dust accession in soils and the resulting problems of interpreting pedogenesis; the erosional-depositional origin of soils in enclosed drainage basins on glacial deposits of Iowa, U.S.A.; the development of a raintower-tilting flume facility and its use in elucidating the processes of soil erosion by flowing water.

Within Australia, carbon capture and storage (CCS) and carbon capture, utilisation and storage will play a significant role as part of an ‘all of the above’ approach to managing greenhouse gas emissions. Two CCS projects are currently operating: Gorgon and the Otway CCS project. The Gorgon and Jansz-Io fields contain approximately 14% carbon dioxide (CO2). The CO2 is brought to shore at Barrow Island and injected into the Dupuy Formation saline aquifer at a depth of 2500 m. While the project has experienced delays with start-up and operational issues, to July 2021 nearly 5 MMt of CO2 had been injected. The Otway CCS Project is a research facility used to study subsurface CO2 storage and behaviour within saline aquifers and depleted reservoirs. Since the start of the project in 2007 a total of 95 000 t of CO2 has been stored. Final Investment Decision was taken for the Moomba CCS project on 1 November 2021 and for the Leigh Creek Urea project in March 2021. In addition, feasibility studies are being carried out across multiple projects within Australia including the South West and Mid-West Projects in the Perth Basin, CarbonNet in Victoria’s Latrobe Valley and Gippsland Basin and the Moonie oil field EOR, Integrated Surat Basin Project and the ATP 2062-P Buckland Basalt projects in the Bowen-Surat Basin. A CCS hub at Bayu-Undan is being assessed as a possible option to reduce the carbon footprint of the Barossa, Caldita and Evans Shoals projects, and feasibility studies are underway into large-scale multi-user CCS hubs near both Darwin and Karratha.

Soil colour is often used as a general purpose indicator of internal soil drainage. In this study we developed a necessarily simple model of soil drainage which combines the tacit knowledge of the soil surveyor with observed matrix soil colour descriptions. From built up knowledge of the soils in our Lower Hunter Valley, New South Wales study area, the sequence of well-draining → imperfectly draining → poorly draining soils generally follows the colour sequence of red → brown → yellow → grey → black soil matrix colours. For each soil profile, soil drainage is estimated somewhere on a continuous index of between 5 (very well drained) and 1 (very poorly drained) based on the proximity or similarity to reference soil colours of the soil drainage colour sequence. The estimation of drainage index at each profile incorporates the whole-profile descriptions of soil colour where necessary, and is weighted such that observation of soil colour at depth and/or dominantly observed horizons are given more preference than observations near the soil surface. The soil drainage index, by definition disregards surficial soil horizons and consolidated and semi-consolidated parent materials. With the view to understanding the spatial distribution of soil drainage we digitally mapped the index across our study area. Spatial inference of the drainage index was made using Cubist regression tree model combined with residual kriging. Environmental covariates for deterministic inference were principally terrain variables derived from a digital elevation model. Pearson’s correlation coefficients indicated the variables most strongly correlated with soil drainage were topographic wetness index (−0.34), mid-slope position (−0.29), multi-resolution valley bottom flatness index (−0.29) and vertical distance to channel network (VDCN) (0.26). From the regression tree modelling, two linear models of soil drainage were derived. The partitioning of models was based upon threshold criteria of VDCN. Validation of the regression kriging model using a withheld dataset resulted in a root mean square error of 0.90 soil drainage index units. Concordance between observations and predictions was 0.49. Given the scale of mapping, and inherent subjectivity of soil colour description, these results are acceptable. Furthermore, the spatial distribution of soil drainage predicted in our study area is attuned with our mental model developed over successive field surveys. Our approach, while exclusively calibrated for the conditions observed in our study area, can be generalised once the unique soil colour and soil drainage relationship is expertly defined for an area or region in question. With such rules established, the quantitative components of the method would remain unchanged.

Drip irrigation is the most common method of water application used in Australian vineyards. However it places physical and chemical stress upon soil structure, which may affect soil physical properties, soil water availability and grapevine functioning. Common soil types within Australian vineyards appear vulnerable to soil degradation and there is emerging evidence of such degradation occurring. Two South Australian vineyards (one located at Nuriootpa in the Barossa Valley, the other in the McLaren Vale winegrowing region) were used to examine evidence of altered soil physical properties due to irrigation. Significantly higher soil strength and lower permeability was found under or near the dripper in irrigated soils. There was also evidence that irrigation increased subsoil bulk density at Nuriootpa. It was uncertain how irrigation caused these changes. While sodicity was present at Nuriootpa, it appeared the physical pressures exerted by irrigation, such as rapid wetting and prolonged wetness, also contributed. To gauge the severity of the degradation at Nuriootpa, a modelling study assessed the impact of higher soil strength and salinity on grapevine transpiration. The SWAP model (Soil- Water-Atmosphere-Plant) was modified and then calibrated using soil moisture data from Nuriootpa. Simulations were conducted for different irrigation regimes and the model output indicated that degradation led to a reduction in cumulative transpiration, which was almost entirely due to higher soil strength. However the reduction was relatively minor and there was evidence of water extraction by roots in all soil layers. Hence the degradation, in terms of higher soil strength and salinity, was not considered a significant management problem in the short - term. Evidence of increased waterlogging and its consequences require further investigation. Roots were observed in soils at Nuriootpa with penetration resistance (PR) much greater than 2 MPa, which was thought to completely impede grapevine root growth. It was hypothesised that roots avoided the physically hostile matrix by using biopores or structural cracks. A pot experiment tested this hypothesis and examined the relationship between soil strength, biopores and root growth for grapevines. Grapevine rootlings (cv. Cabernet Sauvignon) were grown into pots with varying degrees of soil compaction, with and without artificial biopores. No root growth occurred when PR>2 MPa unless biopores were present. Pores also improved root growth in non-compacted soil when PR approached 1 MPa, which suggested biopores influence root growth in soils regardless of compaction levels. Therefore PR should not be the only tool used to examine the rooting-potential of a vineyard soil. An assessment of soil structure, such as biopore density and size, should be incorporated. In drip-irrigated vineyards, there is a possibility that degraded clayey subsoils could be ameliorated by manipulating zones of soil drying. At distances away from the dripper, drying events could generate shrinkage cracks that improve drainage and provide opportunities for root growth. From a practical perspective, drying events could be manipulated by moving the dripper laterally or by changing the irrigation frequency and intensity. The potential of this simple, non-invasive, ameliorative approach was investigated. Large, intact cores were sampled from Nuriootpa subsoil where degradation had been identified. Individual core bulk density was calculated using a formula that was derived by solving two common soil physics equations simultaneously. This proved to be an accurate and non - invasive method. Half the cores were leached with a calcium solution, and the saturated hydraulic conductivity (K [subscript s] ) was measured on all cores before and after drying to a matric potential of -1500 kPa. Soil drying led to a significant increase in K [subscript s], which indicated an improvement in structure through the creation of shrinkage cracks and heaving. Calcium treatment had no impact on K [subscript s], but that could change with more wetting and drying cycles. Results indicated the need for further investigation in the field, where different compressive and tensile forces operate. Harnessing this mechanism may provide an attractive soil management option for growers. The soil physical degradation identified is concerning for sustainable production in irrigated vineyards. Given the sites were representative of typical irrigation practices, such degradation may be widespread. While modelling suggested the impact of higher soil strength and salinity was minimal, these properties should be monitored because they may worsen with continuing irrigation. Furthermore, the impact of irrigation on subsoil permeability needs to be defined more accurately. An increased incidence of waterlogging could significantly restrict production, which was evident when overly wet growing seasons were modelled. If subsoil permeability was found to be significantly lower in irrigated soils, amelioration may be required. In this instance, the use of drying events to generate structure provides an option. Ultimately, the impact of drip irrigation on soil physical quality warrants further attention, and it is imperative to monitor the physical quality of vineyard soils to ensure sustainable production.
Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2007.

Weathering of rocks is the crucial first step in making vineyards possible. For where the debris produced by weathering—the sediment we met in Chapter 5—becomes mixed with moist humus, it will be capable of supporting higher plant life. And thus we have soil, that fundamental prerequisite of all vineyards, indeed of the world’s agriculture. So how does this essential process of weathering come about? Any bare rock at the Earth’s surface is continually under attack. Be it a rocky cliff, a stone cathedral, or a tombstone, there will always be chemical weathering—chemical reactions between its surface and the atmosphere A freshly hewn block of building stone may look indestructible, but before long it will start to look a bit discolored and its surface a little crumbly. We are all familiar with an analogy of this: a fresh surface of iron or steel reacting with moisture and oxygen in the air to form the coating we call rust. In his “Guide to the Lakes” of England, William Wordsworth put the effects of weathering far more picturesquely: “elementary particles crumbling down, over-spread with an intermixture of colors, like the compound hues of a dove’s neck.” A weathered rock is one that is being weakened, broken down. The rock fragments themselves are further attacked, which is why stones in a vineyard often show an outer coating of discolored material, sometimes referred to as a weathering rind (Figure 9.1; see Plate 22). If the stone is broken open, it may show multiple zones of differing colors paralleling the outer surface of the fragment and enclosing a core of fresh rock. Iron minerals soon weather to a powdery combination of hematite, goethite, and limonite, and the rock takes on a reddish-brown, rusty-looking color. The great example of such weathering in viticulture is the celebrated terra rossa, but the rosy soils in parts of Western Australia and places further east such as McLaren Vale and the Barossa Valley are also due to iron minerals. Several Australian wines take their names from this “ironstone.”

As outlined in chapter 1, “determining the site” in old established wine regions such as Burgundy, Tuscany, and the Rheingau has been achieved through centuries of acquired knowledge of the interaction between climate, soil, and grape variety. Commonly, vines were planted on the shallow soils of steep slopes, leaving the more productive lower terraces and flood plains for the cultivation of cereal crops and other food staples, as shown, for example, by the vineyards along the Rhine River in Germany. The small vineyard blocks of the Rhine River, the Côte d’Or, Valais and Vaud regions of Switzerland allowed winegrowers to dif­ferentiate sites on the basis of the most favorable combination of local climate and soil, which underpinned the concept of terroir. In much of the New World, by contrast, where agricultural land was abundant and population pressure less, vineyards have been established on the better soils of the plains and river valleys, as exemplified by such regions as the Central Valley of California, the Riverina in New South Wales, Australia, and Marlborough in New Zealand. Apart from the availability of land, the overriding factor governing site selection was climate and the suitability of particular varieties to the prevailing regional climate. In such regions, although soil variability undoubtedly occurred, plantings of a single variety were made on large areas and vineyard blocks managed as one unit. Soil type and soil variability were largely ignored. Notwithstanding this approach to viticulture in New World countries, in recent time winegrowers aiming at the premium end of the market have become more focused on matching grape varieties to soil and climate and adopting winemaking techniques to attain specific outcomes for their products. For established vineyards, one obvious result of this change is the appearance of “single vineyard” wines that are promoted as expressing the sense of place or terroir. Another reflection of this attitudinal change is the application of precision viticulture (see “Managing Natural Soil Variability in a Vineyard,” chapter 6), whereby vineyard management and harvesting are tailored to the variable expression of soil and local climate in the yield and sensory characteristics of the fruit and wine.

Rainbow Beach is a small town on the coastal dunes of eastern Australia, near Brisbane. I had travelled there to meet with some colleagues to sample soils from the vast coastal sand dunes that surround the area. It might seem an unusual place to visit to collect soil, but a unique sequence of soils has formed in the sand dunes, which differ greatly in age. As you move inland from the sea, the soils get progressively older and deeper, and more weathered and nutrient-poor. The youngest soils are shallow, having only just started to form in recent sand dunes, whereas the oldest soils are around half a million years old and can reach 25 metres deep. These are among the oldest, deepest, and most weathered soils that I have sampled, and what I recall most vividly is how stunted and sparse the vegetation was that grew there, reflecting their struggle to grow in such ancient, weathered soil. The soils of Rainbow Beach are by no means the oldest on Earth. Hidden beneath ice sheets in Greenland, scientists recently discovered a soil that was 2.7 million years old, a remnant of the fertile tundra that covered the area before the ice sheets came. And scientists working in South Africa recently discovered a soil, now compacted in rock, that is 3 billion years old. One of the most fascinating things about soil is that it is incredibly diverse; soils vary enormously across continents, countries, and from valley to valley and field to field. Even within a small patch of land, such as a field, forest, or vegetable garden, the underlying soil can vary considerably. Over distances of metres, it might differ in its texture and depth, and in its pH, being acid in one patch of a field and neutral in another. Soils also vary greatly in the diversity of living organisms that live within them. I will go into more detail about the diversity of soil life later in this book; but for now suffice to say that it is vast. Soils also change with time.