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1
Harper, R. J., R. J. Gilkes, M. J. Hill, and D. J. Carter. "Wind erosion and soil carbon dynamics in south-western Australia." Aeolian Research 1, no. 3-4 (January 2010): 129–41. http://dx.doi.org/10.1016/j.aeolia.2009.10.003.
Повний текст джерела
2
Yang, Xihua, and Bofu Yu. "Modelling and mapping rainfall erosivity in New South Wales, Australia." Soil Research 53, no. 2 (2015): 178. http://dx.doi.org/10.1071/sr14188.
Повний текст джерелаАнотація:
Considerable seasonal and inter-annual changes exist in rainfall amount and intensity in New South Wales (NSW), Australia. These changes are expected to have significant effect on rainfall erosivity and soil erosion by water, but the magnitude of the impact is not well quantified because of the non-linear and dynamic nature of the relationship between rainfall amount and rainfall erosivity. The primary aim of this study was to model spatial and temporal variations in rainfall erosivity and impacts on hillslope erosion across NSW. We developed a daily rainfall erosivity model for NSW to calculate monthly and annual rainfall erosivity values by using gridded daily rainfall data for a continuous 53-year period including a baseline period (1961–90) and a recent period (2000–12). Model parameters were improved based on their geographic locations and elevations to be truly geo-referenced and representative of the regional relationships. Monthly and annual hillslope erosion risk for the same periods was estimated with the Revised Universal Soil Loss Equation. We produced finer scale (100-m) maps of rainfall erosivity and hillslope erosion through spatial interpolation techniques, and implemented the calculation of rainfall erosivity and hillslope erosion in a geographic information system by using automated scripts so that it is fast, repeatable and portable. The modelled rainfall erosivity values were compared with pluviograph calculations and previous studies, and the Nash–Sutcliffe coefficient of efficiency is >0.90. Outcomes from this study provide not only baseline information but also continuous estimates of rainfall erosivity and hillslope erosions allowing better monitoring and mitigation of hillslope erosion risk in NSW.
3
Yang, Xihua, Jonathan Gray, Greg Chapman, Qinggaozi Zhu, Mitch Tulau, and Sally McInnes-Clarke. "Digital mapping of soil erodibility for water erosion in New South Wales, Australia." Soil Research 56, no. 2 (2018): 158. http://dx.doi.org/10.1071/sr17058.
Повний текст джерелаАнотація:
Soil erodibility represents the soil’s response to rainfall and run-off erosivity and is related to soil properties such as organic matter content, texture, structure, permeability and aggregate stability. Soil erodibility is an important factor in soil erosion modelling, such as the Revised Universal Soil Loss Equation (RUSLE), in which it is represented by the soil erodibility factor (K-factor). However, determination of soil erodibility at larger spatial scales is often problematic because of the lack of spatial data on soil properties and field measurements for model validation. Recently, a major national project has resulted in the release of digital soil maps (DSMs) for a wide range of key soil properties over the entire Australian continent at approximately 90-m spatial resolution. In the present study we used the DSMs and New South Wales (NSW) Soil and Land Information System to map and validate soil erodibility for soil depths up to 100 cm. We assessed eight empirical methods or existing maps on erodibility estimation and produced a harmonised high-resolution soil erodibility map for the entire state of NSW with improvements based on studies in NSW. The modelled erodibility values were compared with those from field measurements at soil plots for NSW soils and revealed good agreement. The erodibility map shows similar patterns as that of the parent material lithology classes, but no obvious trend with any single soil property. Most of the modelled erodibility values range from 0.02 to 0.07 t ha h ha–1 MJ–1 mm–1 with a mean (± s.d.) of 0.035 ± 0.007 t ha h ha–1 MJ–1 mm–1. The validated K-factor map was further used along with other RUSLE factors to assess soil loss across NSW for preventing and managing soil erosion.
4
Cooke, JW. "Effect of fallowing practices on runoff and soil erosion in south-eastern Australia." Australian Journal of Experimental Agriculture 25, no. 3 (1985): 628. http://dx.doi.org/10.1071/ea9850628.
Повний текст джерелаАнотація:
The effect on runoff and soil loss of four methods of preparation of fallow was investigated at each of three sites in north-central Victoria. There was a chemical fallow treatment (uncultivated) and three scarified treatments (smooth, medium and rough cultivation). When the results from the three sites were combined, there was 10.7 mm runoff from the uncultivated treatment, 5.1 mm from the smooth, 0.8 mm from the medium and 0.3 mm from the rough scarified treatments. Soil loss from the uncultivated treatment was 103 g/m2 compared with 87 g/m2 from the smooth, 22 g/m2 from the medium and 13 g/m2 from the rough treatment. The concentration of sediment in the runoff was negatively correlated (R2 = -0.56 to -0.98) with runoff. It ranged from 1.21% (w/w) for the uncultivated to 5.06% (w/w) for the rough scarified treatment. The results show that a regimen of minimum scarification to produce a rough surface, and then use of herbicides to control weeds, reduces soil loss compared with either an uncultivated or a smoothly cultivated soil surface.
5
Lu, Hua, Ian P. Prosser, Chris J. Moran, John C. Gallant, Graeme Priestley, and Janelle G. Stevenson. "Predicting sheetwash and rill erosion over the Australian continent." Soil Research 41, no. 6 (2003): 1037. http://dx.doi.org/10.1071/sr02157.
Повний текст джерелаАнотація:
Soil erosion is a major environmental issue in Australia. It reduces land productivity and has off-site effects of decreased water quality. Broad-scale spatially distributed soil erosion estimation is essential for prioritising erosion control programs and as a component of broader assessments of natural resource condition. This paper describes spatial modelling methods and results that predict sheetwash and rill erosion over the Australian continent using the revised universal soil loss equation (RUSLE) and spatial data layers for each of the contributing environmental factors. The RUSLE has been used before in this way but here we advance the quality of estimation. We use time series of remote sensing imagery and daily rainfall to incorporate the effects of seasonally varying cover and rainfall intensity, and use new digital maps of soil and terrain properties. The results are compared with a compilation of Australian erosion plot data, revealing an acceptable consistency between predictions and observations. The modelling results show that: (1) the northern part of Australia has greater erosion potential than the south; (2) erosion potential differs significantly between summer and winter; (3) the average erosion rate is 4.1 t/ha.year over the continent and about 2.9 × 109 tonnes of soil is moved annually which represents 3.9% of global soil erosion from 5% of world land area; and (4) the erosion rate has increased from 4 to 33 times on average for agricultural lands compared with most natural vegetated lands.
6
Yang, Xihua, John Leys, Mingxi Zhang, and Jonathan M. Gray. "Estimating nutrient transport associated with water and wind erosion across New South Wales, Australia." Geoderma 430 (February 2023): 116345. http://dx.doi.org/10.1016/j.geoderma.2023.116345.
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7
Tiller, KG, LH Smith, and RH Merry. "Accessions of atmospheric dust east of Adelaide, South Australia, and the implications for pedogenesis." Soil Research 25, no. 1 (1987): 43. http://dx.doi.org/10.1071/sr9870043.
Повний текст джерелаАнотація:
Atmospheric dust and rainfall were collected at 19 locations within a 90 x 10 km study area extending eastwards from the coast near Adelaide, South Australia. Monthly collections for up to 3 years established seasonal and regional trends in fallout of particulate matter. Fallout was highest in the area of highest rainfall, but correlation of monthly rainfall with fallout was generally not statistically significant. The amount of dust collected was higher under tree foliage than in adjacent open space. Annual accession of atmospheric dust within this urban-rural transect was in the range of 5-10 t km-2 but the occasional severe dust storm could contribute about half the annual rate. These accretions of dust to the landscape, 2.5-5 mm per 1000 years, were about one hundredth of the recommended soil loss tolerance adopted in many studies of soil erosion, and thus unlikely to contribute significantly to models developed for soil loss on that basis. Dust accessions were, however, similar to estimates of rates of soil formation or profile deepening on resistant rocks of 1-5 mm per 1000 years which may be appropriate to conditions in southern Australia. Incorporation of such accessions into existing soils would be difficult to identify yet may provide a significant factor in pedogenesis in the higher rainfall areas. The low rates of soil development in many Australian landscapes, with contribution from both weathering and eolian dust inputs, would encourage the adoption of soil loss tolerances in soil erosion management that are orders of magnitude lower than those commonly accepted.
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Doran-Browne, Natalie A., John Ive, Phillip Graham, and Richard J. Eckard. "Carbon-neutral wool farming in south-eastern Australia." Animal Production Science 56, no. 3 (2016): 417. http://dx.doi.org/10.1071/an15541.
Повний текст джерелаАнотація:
Ruminant livestock production generates higher levels of greenhouse gas emissions (GHGE) compared with other types of farming. Therefore, it is desirable to reduce or offset those emissions where possible. Although mitigation options exist that reduce ruminant GHGE through the use of feed management, flock structure or breeding management, these options only reduce the existing emissions by up to 30% whereas planting trees and subsequent carbon sequestration in trees and soil has the potential for livestock emissions to be offset in their entirety. Trees can introduce additional co-benefits that may increase production such as reduced salinity and therefore increased pasture production, shelter for animals or reduced erosion. Trees will also use more water and compete with pastures for water and light. Therefore, careful planning is required to locate trees where the co-benefits can be maximised instead of any negative trade-offs. This study analysed the carbon balance of a wool case study farm, Talaheni, in south-eastern Australia to determine if the farm was carbon neutral. The Australian National Greenhouse Gas Inventory was used to calculate GHGE and carbon stocks, with national emissions factors used where available, and otherwise figures from the IPCC methodology being used. Sources of GHGE were from livestock, energy and fuel, and carbon stocks were present in the trees and soil. The results showed that from when the farm was purchased in 1980–2012 the farm had sequestered 11 times more carbon dioxide equivalents (CO2e) in trees and soil than was produced by livestock and energy. Between 1980 and 2012 a total of 31 100 t CO2e were sequestered with 19 300 and 11 800 t CO2e in trees and soil, respectively, whereas farm emissions totalled 2800 t CO2e. There was a sufficient increase in soil carbon stocks alone to offset all GHGE at the study site. This study demonstrated that there are substantial gains to be made in soil carbon stocks where initial soils are eroded and degraded and there is the opportunity to increase soil carbon either through planting trees or introducing perennial pastures to store more carbon under pastures. Further research would be beneficial on the carbon-neutral potential of farms in more fertile, high-rainfall areas. These areas typically have higher stocking rates than the present study and would require higher levels of carbon stocks for the farm to be carbon neutral.
9
Bayne, Paul, Robert Harden, and Ian Davies. "Feral goats (Capra hircus L.) in the Macleay River gorge system, north-eastern New South Wales, Australia. I. Impacts on soil erosion." Wildlife Research 31, no. 5 (2004): 519. http://dx.doi.org/10.1071/wr03039.
Повний текст джерелаАнотація:
The impact of feral goats (Capra hircus) on the rate of erosion in steep gorge country was estimated. The erosion (sediment flux) in a manipulated treatment area before and after the removal of goats was compared with erosion in two adjacent unmanipulated areas: one with goats at high density (~20 goats km–2) and one with very few goats (~0.2 goats km–2). Erosion was measured with 36 2-m-wide catch fences, collecting debris (soil and rock) moving down 40° slopes over 10 collection periods spanning 31 months. In the central manipulated area, goats were initially at high density but were completely removed during the third collection period. Over the 10 collection periods, erosion was consistently greater in the area with many goats than in the area with few goats (mean five times greater, range 2.4–11.8). This difference was significant for 6 of the 10 collection periods. Before goats were removed from the manipulated treatment, the erosion in this area was not significantly different from that in the area with many goats, but was significantly greater than the area with few goats. After goat removal erosion in the manipulated area decreased relative to each of the other treatments. By the final collection period erosion in the manipulated (goats removed) area was significantly less than in the area with many goats, but not significantly different from the area with few goats. Initial reduction in erosion following goat removal was rapid, followed by a continued slower decline over the next two years coincident with a relative increase in ground-cover vegetation. It was thought that both direct physical disturbance by the goats and secondary effects due to goat impacts on the substrate and ground-cover vegetation contributed to the increase in erosion associated with the presence of goats.
10
Yang, Xihua. "Deriving RUSLE cover factor from time-series fractional vegetation cover for hillslope erosion modelling in New South Wales." Soil Research 52, no. 3 (2014): 253. http://dx.doi.org/10.1071/sr13297.
Повний текст джерелаАнотація:
Soil loss due to water erosion, in particular hillslope erosion, can be estimated using predictive models such as the Revised Universal Soil Loss Equation (RUSLE). One of the important and dynamic elements in the RUSLE model is the cover and management factor (C-factor), which represents effects of vegetation canopy and ground cover in reducing soil loss. This study explores the potential for using fractional vegetation cover, rather than traditional green vegetation indices (e.g. NDVI), to estimate C-factor and consequently hillslope erosion hazard across New South Wales (NSW), Australia. Values of the C-factor were estimated from the emerging time-series fractional cover products derived from Moderate Resolution Imaging Spectroradiometer (MODIS). Time-series C-factor and hillslope erosion maps were produced for NSW on monthly and annual bases for a 13-year period from 2000 to 2012 using automated scripts in a geographic information system. The estimated C-factor time-series values were compared with previous study and field measurements in NSW revealing good consistency in both spatial and temporal contexts. Using these time-series maps, the relationship was analysed between ground cover and hillslope erosion and their temporal variation across NSW. Outcomes from this time-series study are being used to assess hillslope erosion hazard, sediment and water quality (particularly after severe bushfires) across NSW at local, catchment and regional scales.
11
Yang, Xihua. "Digital mapping of RUSLE slope length and steepness factor across New South Wales, Australia." Soil Research 53, no. 2 (2015): 216. http://dx.doi.org/10.1071/sr14208.
Повний текст джерелаАнотація:
The Universal Soil Loss Equation (USLE) and its main derivate, the Revised Universal Soil Loss Equation (RUSLE), are widely used in estimating hillslope erosion. The effects of topography on hillslope erosion are estimated through the product of slope length (L) and slope steepness (S) subfactors, or LS factor, which often contains the highest detail and plays the most influential role in RUSLE. However, current LS maps in New South Wales (NSW) are either incomplete (e.g. point-based) or too coarse (e.g. 250 m), limiting RUSLE-based applications. The aim of this study was to develop automated procedures in a geographic information system (GIS) to estimate and map the LS factor across NSW. The method was based on RUSLE specifications and it incorporated a variable cutoff slope angle, which improves the detection of the beginning and end of each slope length. An overland-flow length algorithm for L subfactor calculation was applied through iterative slope-length cumulation and maximum downhill slope angle. Automated GIS scripts have been developed for LS factor calculation so that the only required input data are digital elevation models (DEMs). Hydrologically corrected DEMs were used for LS factor calculation on a catchment basis, then merged to form a seamless LS-factor digital map for NSW with a spatial resolution ~30 m (or 1 s). The modelled LS values were compared with the reference LS values, and the coefficient of efficiency reached 0.97. The high-resolution digital LS map produced is now being used along with other RUSLE factors in hillslope erosion modelling and land-use planning at local and regional scales across NSW.
12
Blake, David, Petter Nyman, Helen Nice, Frances M. L. D'Souza, Christopher R. J. Kavazos, and Pierre Horwitz. "Assessment of post-wildfire erosion risk and effects on water quality in south-western Australia." International Journal of Wildland Fire 29, no. 3 (2020): 240. http://dx.doi.org/10.1071/wf18123.
Повний текст джерелаАнотація:
Investigations of wildfire impact on water resources have escalated globally over the last decade owing to an awareness of climate-related vulnerabilities. Within Australia, research into post-wildfire erosion has focused on water supply catchments in the south-eastern region. Here, we examine post-wildfire erosion risk and its potential for water quality impacts in a catchment in south-western Australia. The catchment of the Harvey River, which drains from forested escarpments onto an agricultural coastal plain and into valuable coastal wetlands, was burnt by wildfire in 2016. The aims of this study were to determine erosion risk across contrasting landforms and variable fire severity, using the Revised Universal Soil Loss Equation (RUSLE), and to determine whether post-fire water quality impacts could be detected at permanent river monitoring stations located on the coastal plain. RUSLE outputs showed erosion hot-spots at intersections of steep terrain and high fire severity and that these areas were confined to forested headwaters and coastal dunes. Monthly water quality data showed conspicuous seasonal patterns, but that sampling frequency was temporally too coarse to pick up predicted event-related effects, particularly given that the pre-existing monitoring sites were distal to the predicted zone of contamination.
13
Tozer, P., and J. Leys. "Dust storms – what do they really cost?" Rangeland Journal 35, no. 2 (2013): 131. http://dx.doi.org/10.1071/rj12085.
Повний текст джерелаАнотація:
Dust storms are frequent in Australia and can have a large impact on the soil resource, the economy and people. There have been few economic studies of the impact of wind erosion worldwide and only one in Australia before this study. While wind erosion impacts on the soil resource at the point of the erosion, the level of economic impact rises as the population and associated infrastructure affected by dust increases. This study estimates the impact on the economy of the state of New South Wales of a single large dust storm called Red Dawn that passed over the eastern coast of Australia on 23 September 2009. Estimates for rural and urban areas are presented with both on- and off-site costs evaluated. The estimated cost is A$299 million (with a range of A$293–A$313 million) with most of the cost being associated with household cleaning and associated activities. The dust storm also impacted on many cities on the coast of the state of Queensland, but their costs are not included in this study. This study demonstrates some, but not all, of the major economic costs associated with wind erosion in Australia. Given the annual average cost of dust storms it is suggested that A$9 million per year would be a conservative estimate of the level of investment required in rural areas for dust mitigation strategies, based on improved land management that could be justified to achieve a positive impact on soil condition and reduce economic losses in rural towns and the more populous coastal cities.
14
Ma, Yuxin, Budiman Minasny, Valérie Viaud, Christian Walter, Brendan Malone, and Alex McBratney. "Modelling the Whole Profile Soil Organic Carbon Dynamics Considering Soil Redistribution under Future Climate Change and Landscape Projections over the Lower Hunter Valley, Australia." Land 12, no. 1 (January 14, 2023): 255. http://dx.doi.org/10.3390/land12010255.
Повний текст джерелаАнотація:
Soil organic carbon (SOC) storage and redistribution across the landscape (through erosion and deposition) are linked to soil physicochemical properties and can affect soil quality. However, the spatial and temporal variability of soil erosion and SOC remains uncertain. Whether soil redistribution leads to SOC gains or losses continues to be hotly debated. These considerations cannot be modelled using conventional soil carbon models and digital soil mapping. This paper presents a coupled-model combining RothPC-1 which considers soil carbon (C) down to 1 m and a soil redistribution model. The soil redistribution component is based on a cellular automata technique using the multi-direction flow (FD8) algorithm. With the optimized input values based on land use, we simulated SOC changes upon soil profiles to 1 m across the Lower Hunter Valley area (11,300 ha) in New South Wales, Australia from the 1970s to 2016. Results were compared to field observations and showed that erosion was predicted mostly in upslope areas and deposition in low-lying areas. We further simulated SOC trends from 2017 until ~2045 in the area under three climate scenarios and five land use projections. The variation in the magnitude and direction of SOC change with different projections shows that the main factors influencing SOC changes considering soil redistribution are climate change which controlled the trend of SOC stocks, followed by land use change. Neglecting soil erosion in carbon models could lead to an overestimation of SOC stocks. This paper provides a framework for incorporating soil redistribution into the SOC dynamics modelling and also postulates the thinking that soil erosion is not just a removal process by surface runoff.
15
Yang, Xihua, Qinggaozi Zhu, Mitch Tulau, Sally McInnes-Clarke, Liying Sun, and Xiaoping Zhang. "Near real-time monitoring of post-fire erosion after storm events: a case study in Warrumbungle National Park, Australia." International Journal of Wildland Fire 27, no. 6 (2018): 413. http://dx.doi.org/10.1071/wf18011.
Повний текст джерелаАнотація:
Wildfires in national parks can lead to severe damage to property and infrastructure, and adverse impacts on the environment. This is especially pronounced if wildfires are followed by intense storms, such as the fire in Warrumbungle National Park in New South Wales, Australia, in early 2013. The aims of this study were to develop and validate a methodology to predict erosion risk at near real-time after storm events, and to provide timely information for monitoring of the extent, magnitude and impact of hillslope erosion to assist park management. We integrated weather radar-based estimates of rainfall erosivity with the revised universal soil loss equation (RUSLE) and remote sensing to predict soil loss from individual storm events after the fire. Other RUSLE factors were estimated from high resolution digital elevation models (LS factor), satellite data (C factor) and recent digital soil maps (K factor). The accuracy was assessed against field measurements at twelve soil plots across the Park and regular field survey during the 5-year period after the fire (2013–17). Automated scripts in a geographical information system have been developed to process large quantity spatial data and produce time-series erosion risk maps which show spatial and temporal changes in hillslope erosion and groundcover across the Park at near real time.
16
Yu, B., and C. J. Rosewell. "Evaluation of WEPP for runoff and soil loss prediction at Gunnedah, NSW, Australia." Soil Research 39, no. 5 (2001): 1131. http://dx.doi.org/10.1071/sr00091.
Повний текст джерелаАнотація:
It is important to use historical data to test physically based runoff and soil erosion prediction models as well as the method to estimate model parameters. WEPP (Water Erosion Prediction Project) was validated for bare fallow and annual wheat treatments at Gunnedah, New South Wales, Australia. Wheat stubble was either burned or mulched. Climate, soil, management, and runoff and soil loss data were collected for the period 1980–87 for 3 bare fallow plots, and 1950–74 for 10 annual wheat plots. Three slope lengths from 21 to 62 m were established for the treatment with stubble burned. Slope steepness varied from 8% to 9% at the site. Effective saturated hydraulic conductivity and soil erodibility parameters were estimated from measured soil properties. No further calibration of these parameters was attempted in order to assess the true potential of the model for runoff and soil loss predictions. WEPP worked well for the bare fallow plots with prediction efficiency of 0.97 for event runoff and soil losses. WEPP generally over-predicted the runoff, and consequently, the soil loss for annual wheat treatments for the site. WEPP was able to predict the effect of slope length on sediment concentration and soil loss for the site. CLIGEN, which provides the continuous climate input to WEPP, was found to produce adequately the mean daily rainfall, but produced higher than expected peak rainfall intensity, resulting in higher runoff and soil loss for all treatments.
17
Fritsch, E., and RW Fitzpatrick. "Colour plates - Interpretation of soil features produced by ancient and modern processes in degraded landscapes .1. A new method for constructing conceptual soil-water-landscape models." Soil Research 32, no. 5 (1994): 880. http://dx.doi.org/10.1071/sr9940880.
Повний текст джерелаАнотація:
A pedo-hydrological method which involves interpreting features in soils that result from both ancient and modern processes along toposequences in a subcatchment of the Mt Lofty Ranges, South Australia, is used to construct conceptual soil-water-landscape models. This method links soil-landscape features to soil-water processes with strong emphasis on: (i) soil water-flow systems and (ii) soil-forming and soil-change processes. The conceptual model illustrates the interactions between soil processes acting in soil water-flow systems. This model is able to predict future modes of soil-landscape evolution under changing environmental conditions. As well, it may be used by land and water supply managers to develop more efficient management strategies under conditions of increasing land degradation (e.g. erosion and water pollution). A typical Palexeralf-Natraqualf hydro-toposequence of soils (i.e. catena consisting of red-yellow-grey duplex soils) is used as an example to illustrate this new approach. The landscape selected is undergoing severe soil degradation (i.e. waterlogging, dryland salinity, erosion and water pollution). The constructed conceptual soil-water-landscape model is the result of detailed pedo-hydrological investigations along toposequences in a representative subcatchment in the high rainfall zone (>600 mm) of the Mount Lofty Ranges, South Australia. The model illustrates in graphic form interactions between three soil water-flow systems (freely drained red soil system, hydromorphic topsoil system, hydromorphic subsoil system) and eight soil processes (saprolitization, ferralitization, glaebulization, redoximorphism, eluviation/illuviation, salinization/solonization, sulfidization/sulfuricization and water erosion). The study demonstrates that this whole ecosystem has been placed into disequilibrium thereby developing severe land degradation problems as a result of rising saline sulfatic ground watertables and perched watertables due to land-clearing since European settlement. The purpose of this paper is to provide a methodology framework and overall summary for other papers in a series dealing essentially with detailed field and laboratory investigations of individual soil-water processes.
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Fritsch, E., and RW Fitzpatrick. "Interpretation of soil features produced by ancient and modern processes in degraded landscapes .1. A new method for constructing conceptual soil-water-landscape models." Soil Research 32, no. 5 (1994): 889. http://dx.doi.org/10.1071/sr9940889.
Повний текст джерелаАнотація:
A pedo-hydrological method which involves interpreting features in soils that result from both ancient and modern processes along toposequences in a subcatchment of the Mt Lofty Ranges, South Australia, is used to construct conceptual soil-water-landscape models. This method links soil-landscape features to soil-water processes with strong emphasis on: (i) soil water-flow systems and (ii) soil-forming and soil-change processes. The conceptual model illustrates the interactions between soil processes acting in soil water-flow systems. This model is able to predict future modes of soil-landscape evolution under changing environmental conditions. As well, it may be used by land and water supply managers to develop more efficient management strategies under conditions of increasing land degradation (e.g. erosion and water pollution). A typical Palexeralf-Natraqualf hydro-toposequence of soils (i.e. catena consisting of red-yellow-grey duplex soils) is used as an example to illustrate this new approach. The landscape selected is undergoing severe soil degradation (i.e. waterlogging, dryland salinity, erosion and water pollution). The constructed conceptual soil-water-landscape model is the result of detailed pedo-hydrological investigations along toposequences in a representative subcatchment in the high rainfall zone (>600 mm) of the Mount Lofty Ranges, South Australia. The model illustrates in graphic form interactions between three soil water-flow systems (freely drained red soil system, hydromorphic topsoil system, hydromorphic subsoil system) and eight soil processes (saprolitization, ferralitization, glaebulization, redoximorphism, eluviation/illuviation, salinization/solonization, sulfidization/sulfuricization and water erosion). The study demonstrates that this whole ecosystem has been placed into disequilibrium thereby developing severe land degradation problems as a result of rising saline sulfatic ground watertables and perched watertables due to land-clearing since European settlement. The purpose of this paper is to provide a methodology framework and overall summary for other papers in a series dealing essentially with detailed field and laboratory investigations of individual soil-water processes.
19
Walker, PH. "Contributions to the understanding of soil and landscape relationships." Soil Research 27, no. 4 (1989): 589. http://dx.doi.org/10.1071/sr9890589.
Повний текст джерелаАнотація:
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.
20
Radke, L. C., I. P. Prosser, M. Robb, B. Brooke, D. Fredericks, G. B. Douglas, and J. Skemstad. "The relationship between sediment and water quality, and riverine sediment loads in the wave-dominated estuaries of south-west Western Australia." Marine and Freshwater Research 55, no. 6 (2004): 581. http://dx.doi.org/10.1071/mf04044.
Повний текст джерелаАнотація:
We examine surface sediment and water column total nutrient and chlorophyll a concentrations for 12 estuaries with average water depths <4 m, and calculated sediment loads ranging from 0.2 to 10.8 kg m−2 year−1. Sediment total nitrogen, phosphorus and organic carbon concentrations vary inversely with sediment loads due to: (i) the influx of more mineral-rich sediment into the estuaries; and (ii) increasing sediment sulfidation. Sediment total organic carbon (TOC) : total sulfur (TS) and TS : Fe(II) ratios correlated to sediment loads because enhanced sedimentation increases burial, hence the importance of sulfate reduction in organic matter degradation. Curvilinear relationships were found between a weathering index and organic matter δ13C in sediment, and sediment load. The rising phase of the curve (increasing weathering, lighter isotopic values) at low to intermediate loads relates to soil erosion, whereas regolith or bedrock erosion probably explains the declining phase of the curve (decreasing weathering, heavier isotopic values) at higher sediment loads. The pattern of change for water column total nutrients (nitrogen and phosphorus) with sediment loads is similar to that of the weathering index. Most water quality problems occur in association with soil erosion, and at sediment loads that are intermediate for the estuaries studied. Limited evidence is presented that flushing can moderate the impact of sediment loads upon the estuaries.
21
Poch, R. M., B. P. Thomas, R. W. Fitzpatrick, and R. H. Merry. "Micromorphological evidence for mineral weathering pathways in a coastal acid sulfate soil sequence with Mediterranean-type climate, South Australia." Soil Research 47, no. 4 (2009): 403. http://dx.doi.org/10.1071/sr07015.
Повний текст джерелаАнотація:
Soil micromorphology, using light microscopy and scanning electron microscopy (SEM), was used to describe detailed soil morphological and compositional changes and determine mineral weathering pathways in acid sulfate soils (ASS) from the following 2 contrasting coastal environments in Barker Inlet, South Australia: (i) a tidal mangrove forest with sulfidic material at St Kilda, and (ii) a former supratidal samphire area at Gillman that was drained in 1954 causing sulfuric material to form from sulfidic material. Pyrite framboids and cubes were identified in sulfidic material from both sites and are associated with sapric and hemic materials. Gypsum crystals, interpreted as a product of sulfide oxidation, were observed to have formed in lenticular voids within organic matter in the tidal mangrove soils at St Kilda. Sulfide oxidation was extensive in the drained soil at Gillman, evidenced by the formation of iron oxyhydroxide pseudomorphs (goethite crystallites and framboids) after pyrite and jarosite, and of gypsum crystals. Gypsum crystals occur where a local source of calcium such as shells or calcareous sand is present. Sporadic oxidation episodes are indicated by the formation of iron oxide and jarosite coatings around coarse biogenic voids. These observations indicate that mineral transformation pathways are strongly influenced by soil physico-chemical characteristics (i.e. oxidation rate, Eh, pH, soil solution chemistry, mineralogy, and spatial distribution of sulfides). This information has been used to illustrate the interrelationships of pyrite, carbonate, gypsum, jarosite, and organic matter and help predict soil evolution under changing hydro-geochemical, redoximorphic, and thermal conditions in soils from coastal environments.
22
Sudmeyer, R. A., and P. R. Scott. "Characterisation of a windbreak system on the south coast of Western Australia. 1. Microclimate and wind erosion." Australian Journal of Experimental Agriculture 42, no. 6 (2002): 703. http://dx.doi.org/10.1071/ea02007.
Повний текст джерелаАнотація:
The lack of data relating changes in microclimate and wind erosion to crop growth in shelter is a constraint to the adoption of windbreak systems in Australia. In this experiment microclimate and soil movement were measured in a 450 m wide bay between 2 Pinus pinaster windbreaks in south-western Australia over 4 years. Changes in wind speed and microclimate as a result of wind shelter varied spatially and temporally. When the wind direction was perpendicular to the windbreaks, wind-run reductions greater than 20% extended 18 times the height of the windbreak (H) downwind. However, over the whole growing season wind-run reductions greater than 20% only extended 3–6 H from the windbreaks, and were confined to within 4 H over the whole year. Over the growing season, atmospheric vapour pressure and average daily temperature and potential evaporation in the most sheltered part of the windbreak bay were generally within ± 5–10% of unsheltered values. While growing conditions were generally improved, there were periods at the end of the growing season when sheltered crops experienced increased air temperatures and vapour pressure deficit. The principal benefit of the windbreaks appeared to be reducing wind speed during periods with short duration erosive winds. More than 1 H from the windbreaks, wind erosion was reduced for 36 H downwind of the windbreak that provided most shelter during the period of maximum soil movement. Browsing stock increased the porosity of the lower 1.5 m of the windbreaks, which allowed wind to funnel under the windbreaks. This study highlights the difficulty of maintaining constant shelter in an environment where the prevailing wind direction changes throughout the year and the need to orient windbreaks to provide shelter during those times when strong winds are most damaging to soils or crops.
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Gray, Jonathan M., Greg A. Chapman, and Brian W. Murphy. "Land management within capability: a new scheme to guide sustainable land management in New South Wales, Australia." Soil Research 53, no. 6 (2015): 683. http://dx.doi.org/10.1071/sr14196.
Повний текст джерелаАнотація:
A new evaluation scheme, land management within capability (LMwC), used to guide sustainable land management in New South Wales (NSW), is presented. The scheme semi-quantitatively categorises the potential impacts of specific land-management actions and compares these with the inherent physical capability of the land in relation to a range of land-degradation hazards. This leads to the derivation of LMwC indices, which signify the sustainability of land-management practices at the scale of individual sites up to broader regions. The LMwC scheme can be used to identify lands at greatest risk from various land-degradation hazards. It can help to guide natural resource agencies at local, regional and state levels to target priorities and promote sustainable land management across their lands. Few other schemes that assess the sustainability of a given land-management regime in a semi-quantitative yet pragmatic manner are found in the literature. The scheme has particular application for regional soil-monitoring programs and it was applied in such a program over NSW in 2008–09. The results suggested that the hazards most poorly managed across the state are wind erosion, soil acidification and soil organic carbon decline. The LMwC scheme, or at least its underlying concepts, could be readily applied to other jurisdictions.
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Braunack, MV. "The effect of tracked vehicles on soil strength and micro-relief of a calcareous earth (Gc1.12) North of Woomera, South Australia." Rangeland Journal 7, no. 1 (1985): 17. http://dx.doi.org/10.1071/rj9850017.
Повний текст джерелаАнотація:
Changes in soil strength and surface micro-relief were measured in a calcareous earth (Gc. 1.12) at a site north of Woomera, before and after the passage of a tracked vehicle. The passage of a tracked vehicle resulted in a reduction of ?oil strength and the formation of ruts. The degree of change depended on the number of vehicle passes and whether the vehicle was travelling in a straight line or turning. Implications for erosion are discussed.
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Shan, Linxin, Xihua Yang, and Qinggaozi Zhu. "Effects of DEM resolutions on LS and hillslope erosion estimation in a burnt landscape." Soil Research 57, no. 7 (2019): 797. http://dx.doi.org/10.1071/sr19043.
Повний текст джерелаАнотація:
The combined slope length and slope steepness factor (LS) is crucial in soil erosion models such as the revised universal soil loss equation (RUSLE), and is often calculated from digital elevation models (DEMs). With high-resolution DEMs becoming increasingly available in recent years, we face considerable challenges in selecting the optimal DEM for erosion modelling. In this paper, we present a case study on LS factor computation using various DEMs at resolutions ranging from 1 to 90 m over a burnt national park in New South Wales, Australia, aiming to assess the effects of DEM resolution on LS and hillslope erosion estimation. The LS was calculated based on RUSLE specifications and incorporated a variable cutoff slope angle that improves the detection of the beginning and the end of each slope length. Results show the trend of an increase in the estimated LS value as the DEM resolution became coarser. We consider 5–10-m DEMs to have optimal resolution because the LS values calculated at this range were closer to the LS values measured at the 12 soil plots over the study area. We also assessed different sampling methods for LS value extraction and statistical analysis. The sampling method based on contributing area was more representative compared with point-based and buffer sampling methods. Findings from this study will be useful for choosing the optimal DEM resolution and sampling method in hillslope erosion modelling.
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Schultz, JE. "Crop production in a rotation trial at Tarlee, South Australia." Australian Journal of Experimental Agriculture 35, no. 7 (1995): 865. http://dx.doi.org/10.1071/ea9950865.
Повний текст джерелаАнотація:
A crop rotation trial was established in 1977 on a hard-setting red-brown earth at Tarlee, South Australia, to monitor the long-term effect of intensive and traditional rotations on soil properties and crop production. The rotations involve wheat alternating with cereals, grain legumes, pasture, and fallow. There are 3 stubble + tillage treatments: remove stubble + cultivate, retain stubble + cultivate, retain stubble + no tillage. Three rates of nitrogen (0,40, 80 kg N/ha as ammonium nitrate) are applied to the wheat. Grain yield varied with seasonal conditions, and water use efficiencies were up to 10 kg/ha. mm. In the more productive rotations, wheat grain yields expressed as a percentage of potential yield tended to increase over time. The best wheat yields were always in rotations that included a grain legume or legume pasture, with additional yield increases in all rotations coming from the use of N fertiliser. By comparison with rotation and N fertiliser effects, there was little effect of the stubble + tillage treatments on grain yield. Most of the yield variations were related to differences in tiller density or grains per ear, with grain weight remaining relatively constant over all seasons. There was a tendency for grain legume yields to decrease over the latter years of the trial, and this was attributed to the build-up of plant diseases through growing the same species on the same plot every second year. Overall, faba beans were the highest yielding grain legume, and the wheat-beans rotation, with 80 kg N/ha on the wheat, gave highest total grain production. Data for residue remaining after harvest indicate that in some years there is less than the desired minimum levels to give adequate protection against erosion, so any grazing of the residues must be carefully managed.
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Eldridge, DJ, and TB Koen. "Run-Off and Sediment Yield From a Semi-Arid Woodland in Eastern Australia. Ii. Variation in Some Soil Hydrological Properties Along a Gradient in Soil Surface Condition." Rangeland Journal 15, no. 2 (1993): 234. http://dx.doi.org/10.1071/rj9930234.
Повний текст джерелаАнотація:
Three sites on red earth soils were examined at Yathong Nature Reserve and 'Coan Downs' in central- western New South Wales. The sites represented a gradient in soil surface condition from a stable, uneroded and productive site, supporting moderately dense perennial grasses (site 1) to a moderately unstable and degraded site with few perennials and evidence of erosion (site 3). The hydrological characteristics of the three sites were measured using a rainfall simulator on plots with varying vegetation cover. Water ponded earlier at the degraded site, and run-off and sediment removal increased as the soil surface became more degraded. Associated with this was an increase in the importance of vegetation cover, and a decrease in the importance of soil physico-chemical variables as descriptors of soil hydrological properties. The results are consistent with the notion that vegetation plays a more important role in maintaining soil hydrological processes as the soil surface becomes more degraded.
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Murphy, Brian, and Peter Fogarty. "Application of the Soil Security Concept to Two Contrasting Soil Landscape Systems—Implications for Soil Capability and Sustainable Land Management." Sustainability 11, no. 20 (October 16, 2019): 5706. http://dx.doi.org/10.3390/su11205706.
Повний текст джерелаАнотація:
Soil security identifies global challenges and a series of dimensions that are necessary requirements to meet those global challenges using sustainable land management. The soil security concept is applied to two contrasting soil landscape systems with varying climate, landform and soil types. Previous methodologies for assessing land and soil capability are combined within the soil security conceptual approach. The land and soil capability methodologies are used to assess how the soil condition changes in response to the stresses and forcing associated with land management and land and soil degradation processes. It is the soil capability that defines how the soil condition changes between the reference state of the soil condition, or the genoform, and the soil condition under land use, or the phenoform. The conclusion is that soil capability, which is one of the dimensions used to apply the soil security concept, is a complex dimension and has several aspects or further facets to be considered to achieve sustainable land management. It is apparent that in assessing soil capability, the following facets are relevant. I: The capacity of the soil to provide ecosystem services to meet the global challenges outlined for Soil Security. II: The stability of the soil condition to land degradation processes resulting from the effects of land management practices and the environmental stresses on the soil. III: The capacity to recover following degradation. Facets II and III can be considered the resilience. An important conclusion is that the soil capability cannot be assessed without taking into account features of the landscape including climate and landform. Two examples from south eastern Australia of the application of these facets of soil capability to on-ground situations are presented. The Cowra Trough Red Soils in the Australian wheat belt are a set of soils, primarily contributing to meeting the global challenge of food security. The major degradation processes threatening the stability of these soils are water erosion and soil acidification. The Kosciusko National Park in the Snowy Mountains region is primarily contributing to meeting the challenges of water security for the irrigation industry in the Murray Darling Basins and energy security through the production of hydroelectricity. The set of soil landscapes also contributes to biodiversity protection and human health and well-being. The major degradation processes threatening the stability of these soils and their capacity to meet the global challenges are water and wind erosion. A major limitation is the poor capacity of these soils to recover once degraded. Identifying the main ecosystem services provided by the two examples, together with the major risks of land degradation can clarify extension, economic and policy aspects of sustainable land management for the two sets of soil landscapes. For the Cowra Trough Red Soils, management of water erosion and soil acidification are essential for maintaining the contribution of the area to food security. For the Kosciusko National Park, the control of water and wind erosion are essential to maintain the contribution of the area to water and energy security.
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Sheridan, Gary J., Petter Nyman, Christoph Langhans, Jane Cawson, Philip J. Noske, Akiko Oono, Rene Van der Sant, and Patrick N. J. Lane. "Is aridity a high-order control on the hydro–geomorphic response of burned landscapes?" International Journal of Wildland Fire 25, no. 3 (2016): 262. http://dx.doi.org/10.1071/wf14079.
Повний текст джерелаАнотація:
Fire can result in hydro–geomorphic changes that are spatially variable and difficult to predict. In this research note we compile 294 infiltration measurements and 10 other soil, catchment runoff and erosion datasets from the eastern Victorian uplands in south-eastern Australia and argue that higher aridity (a function of the long-term mean precipitation and net radiation) is associated with lower post-fire infiltration capacities, increasing the chance of surface runoff and strongly increasing the chance of debris flows. Post-fire debris flows were only observed in the more arid locations within the Victorian uplands, and resulted in erosion rates more than two orders of magnitude greater than non-debris flow processes. We therefore argue that aridity is a high-order control on the magnitude of post-wildfire hydro–geomorphic processes. Aridity is a landscape-scale parameter that is mappable at a high resolution and therefore is a useful predictor of the spatial variability of the magnitude of post-fire hydro–geomorphic responses.
30
Peterson, David J., and Raj Prasad. "The biology of Canadian weeds. 109. Cytisus scoparius (L.) Link." Canadian Journal of Plant Science 78, no. 3 (July 1, 1998): 497–504. http://dx.doi.org/10.4141/p97-079.
Повний текст джерелаАнотація:
Scotch broom (Cytisus scoparius [L.] Link.) is an exotic perennial, leguminous, deciduous shrub, which during the past century has greatly expanded its range along the Pacific and Atlantic coasts of North America, and in Australia, New Zealand, South Africa, Chile, Iran, and India. This shrub rapidly invades disturbed areas, forming dense thickets, which can suppress and inhibit native vegetation, including economically important conifer seedlings. The developmental characteristics whereby Scotch broom invades new sites include specialized stem photosynthesis, prolific seed production, longevity of seeds in the soil, and nitrogen fixation. Human activities such as planting along highways for beautification and prevention of soil erosion have accelerated the problem of rapid geographical dispersal. Various methods of control (chemical, manual, and biological) together with habitat, morphology, reproductive biology, growth and development are discussed. Key words: Cytisus scoparius, Ulex europaeus, Scotch broom, invasive weeds, bioherbicides, Fusarium tumidu
31
Crockford, R. H., and I. R. Willett. "Application of mineral magnetism to describe profile development of toposequences of a sedimentary soil in south-eastern Australia." Soil Research 39, no. 5 (2001): 927. http://dx.doi.org/10.1071/sr00077.
Повний текст джерелаАнотація:
Mineral magnetism and chemical properties of soil profiles across a valley with an erosion gully in a Yellow Dermosol sedimentary soil suggest that the magnetic profile resulted from a combination of alluviation and pedogenesis. The concentration of soil magnetic minerals in a range of particle sizes (3.36–2 mm to <2 μm) diminished from the surface downwards to a minimum (referred to as layer P), then increased to high values (layer H), after which it decreased to bed rock level at the base layer. It is proposed that the H layer was the surface of a buried soil, and that the ferrimagnetic mineral through the profiles was dominantly maghemite, formed by fire enhancement. The magnetic pattern of the profiles compressed as the soil became shallower up-slope, from 3 m in depth at the lowest site to 0.7 m at a site 40 m up-slope. Above this site the high susceptibility H layer was absent, which is consistent with the H layer being an earlier soil surface. Except for the profile at the very top of the slope (depth of 0.63 m), the magnetic grain size did not vary with depth. In the P layers, there was a greater proportion of paramagnetic minerals than in the other layers. The changes in magnetic susceptibility through the profiles were influenced by ferrimagnetic, paramagnetic, and canted anti-ferromagnetic material. For all depths in all profiles the magnetic susceptibility changed consistently through the particle size range, decreasing from the larger sizes to the 10–20 m size then increasing slightly to the smallest size (<2 μm). The mean magnetic grain size also decreased through the particle size range. Magnetic particles of 3 concentration levels were extracted by a hand magnet from the 4 largest particle sizes and showed the same magnetic-particle size relationships, for both mass susceptibility and magnetic grain size, as the other particle sizes. This showed that the proportion of highly magnetic particles effectively determined the susceptibility and magnetic grain size features of the bulk samples of each particle size class. The particle size/magnetic susceptibility pattern described in this paper occurs in all sedimentary soils and derived river sediments studied in this part of Australia. However, soils and sediments of granitic origin have an inverse pattern. These differences are attributed to pedogenic and geomorphological process. The difficulties in using mineral magnetic properties as a means of sourcing mobile sediments in catchments are discussed.
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Sanderman, Jonathan, I. R. P. Fillery, R. Jongepier, A. Massalsky, M. M. Roper, L. M. Macdonald, T. Maddern, D. V. Murphy, and J. A. Baldock. "Carbon sequestration under subtropical perennial pastures II: Carbon dynamics." Soil Research 51, no. 8 (2013): 771. http://dx.doi.org/10.1071/sr12351.
Повний текст джерелаАнотація:
Here we take advantage of the stable carbon isotope shift that occurs when a C4 plant is sown into a soil previously dominated by C3 vegetation, to explore the movement and fate of newly sequestered soil organic carbon (SOC) following establishment of subtropical perennial pastures in temperate regions of Australia. In kikuyu-based pastures up to 33 years of age, SOC accumulated exclusively in the coarse size fraction (>50 μm) in the sandy soils of southern Western Australia. In South Australian loams, regardless of pasture age, new SOC was found to accumulate in both the coarse and fine (<50 μm) size fractions. These differential results suggest that in soils with low clay content, new SOC remains in an unprotected form that is highly vulnerable to loss through decomposition and erosion. The Rothamsted Carbon Model, modified to track changes in stable isotopes, was able to represent the changes in total SOC stocks in both regions; however, the model over-predicted the incorporation of the new C4-SOC into the soil. This difference between data and model output could be reconciled if a greater proportion of new SOC is rapidly mineralised without being incorporated into any sort of stabilised pool.
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Bradstock, Ross A. "Effects of large fires on biodiversity in south-eastern Australia: disaster or template for diversity?" International Journal of Wildland Fire 17, no. 6 (2008): 809. http://dx.doi.org/10.1071/wf07153.
Повний текст джерелаАнотація:
Large fires coincident with drought occurred in south-eastern Australia during 2001–2007. Perceptions of large, intense fires as being ecologically ‘disastrous’ are common. These are summarised by four hypotheses characterising large fires as: (i) homogenous in extent and intensity; (ii) causing large-scale extinction due to perceived lack of survival and regeneration capacity among biota; (iii) degrading due to erosion and related edaphic effects; (iv) unnatural, as a consequence of contemporary land management. These hypotheses are examined using available evidence and shown to inadequately account for effects of large fires on biodiversity. Large fires do not burn homogeneously, though they may produce intensely burnt patches and areas. The bulk of biota are resilient through a variety of in situ persistence mechanisms that are reinforced by landscape factors. Severe erosive episodes following fire tend to be local and uncertain rather than global and inevitable. Redistribution of soil and nutrients may reinforce habitat variation in some cases. Signals of fire are highly variable over prehistoric and historic eras, and, in some cases, contemporary and pre-European signal levels are equivalent. The most important effects of large fires in these diverse ecological communities and landscapes stem from their recurrence rate. Adaptive management of fire regimes rather than fire events is required, based on an understanding of risks posed by particular regimes to biota.
34
Lawrence, Susan, James Grove, Peter Davies, Jodi Turnbull, Ian Rutherfurd, and Mark Macklin. "Historical dredge mining as a significant anthropomorphic agent in river systems: A case study from south-eastern Australia." Holocene 31, no. 7 (March 25, 2021): 1158–74. http://dx.doi.org/10.1177/09596836211003272.
Повний текст джерелаАнотація:
Bucket dredging to mine and extract gold and tin from rivers is a global industry that has had a range of negative effects on physical environments. These include the destruction of riparian soil profiles and structures, artificial channel straightening and loss of in-stream biodiversity. In this paper we evaluate the immediate effects and long-term consequences of bucket dredging on rivers in Victoria and New South Wales during the period 1900–1950. High quality historical sources on dredge mining are integrated with geospatial datasets, aerial imagery and geomorphological data to analyse the scale of the dredging industry, evidence for disturbance to river channels and floodplains and current land use in dredged areas. The study demonstrates that the environmental impact of dredging was altered but not reduced by anti-pollution regulations intended to control dredging. An assessment of river condition 70–100 years after dredge mining ceased indicates that floodplains and river channels continue to show the effects of dredging, including bank erosion, sediment slugs, compromised habitat and reduced agricultural productivity. These findings have significant implications for river and floodplain management.
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Eyles, Alieta, Garth Coghlan, Marcus Hardie, Mark Hovenden, and Kerry Bridle. "Soil carbon sequestration in cool-temperate dryland pastures: mechanisms and management options." Soil Research 53, no. 4 (2015): 349. http://dx.doi.org/10.1071/sr14062.
Повний текст джерелаАнотація:
Permanent pastures, which include sown, native and naturalised pastures, account for 4.3 Mha (56%) of the national land use in Australia. Given their extent, pastures are of great interest with respect to their potential to influence national carbon (C) budgets and CO2 mitigation. Increasing soil organic C (SOC) mitigates greenhouse gases while providing other benefits such as pasture productivity, soil health and ecosystem services. Several management approaches have been recommended to increase C sequestration in pasture-based systems; however, results have proved variable and often contradictory between sites and years. Here, we present an overview of the processes and mechanisms responsible for C sequestration in permanent pastures. In addition, we discuss the merits of traditional and emerging pasture-management practices for increasing SOC in pastures, with a focus on dryland pasture systems of south-eastern Australia. We conclude by summarising the knowledge gaps and research priorities for soil C-sequestration research in dryland pastures. Our review confirms that soils under a range of pasture types have considerable potential for sequestration of atmospheric CO2 in Australia, and that the magnitude of this potential can be greatly modified by pasture-management practices. Although the shortage of long-term studies under Australian conditions limits our ability to predict the potential of various management approaches to sequester soil C, our review indicates that prevention of erosion through maintenance of groundcover and adoption of options that promote deep C sequestration are likely to confer broad-scale maintenance or increases in SOC in pasture soils over a decade or longer. We acknowledge that the evidence is limited; therefore, confidence in the recommended practices in different locations and climates is largely unknown.
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Sudmeyer, R. A., M. A. Adams, J. Eastham, P. R. Scott, W. Hawkins, and I. C. Rowland. "Broadacre crop yield in the lee of windbreaks in the medium and low rainfall areas of south-western Australia." Australian Journal of Experimental Agriculture 42, no. 6 (2002): 739. http://dx.doi.org/10.1071/ea02011.
Повний текст джерелаАнотація:
In Western Australia, the paucity of documented information detailing crop yield in the lee of windbreaks is a constraint to the adoption of tree windbreaks in dryland farming systems. This paper presents grain yield data for crops growing in the lee of windbreaks in the medium to low rainfall areas of the south-west of Western Australia for 64 field years between 1994 and 1997. Two distinct areas were identified in the lee of windbreaks: a zone of reduced crop yield extending 3–5 times the windbreak height (H) from the trees (competition zone), and a zone of unchanged or improved yield extending 15–20 H (sheltered zone). Yield between 1 and 20 H was less than unsheltered yield in years with average rainfall, similar to unsheltered yield in years, or areas, with low rainfall and higher than unsheltered yield if the unsheltered crop was subjected to sandblasting. Changes in microclimate in shelter appeared to be of benefit in increasing crop yields in drier years or areas. Lupin yield was generally increased in the sheltered zone while cereal yield was generally unchanged. The rate of canopy development may be critical to crop response. In dry years, reduced wind speed in shelter reduced evaporation of soil moisture, increasing the amount of soil water available to establishing crops and reducing sandblasting damage. The principle benefit of windbreaks was their ability to reduce wind erosion and subsequent crop damage. As such, windbreaks are best regarded as a form of insurance.
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Sanjari, Gholamreza, Bofu Yu, Hossein Ghadiri, Cyril A. A. Ciesiolka, and Calvin W. Rose. "Effects of time-controlled grazing on runoff and sediment loss." Soil Research 47, no. 8 (2009): 796. http://dx.doi.org/10.1071/sr09032.
Повний текст джерелаАнотація:
The time-controlled rotational grazing (TC grazing) has become popular in Australia and elsewhere in the world to provide graziers and ranchers with improved productivity over traditional practices. However, this grazing system, which involves short periods of intensive grazing, has raised concerns about sustainability and environmental impacts on water and soil resources, and ecosystem health generally. A runoff experiment at the catchment scale was established on the grazing property ‘Currajong’ in the south-east region of Queensland, Australia, to investigate the effects of continuous and TC grazing on runoff and sediment generation from 2001 to 2006. Sediment loss was reduced significantly under TC grazing compared with continuous grazing irrespective of the size of runoff events. This effect was more pronounced in the catchments with soils of gentler slopes and greater depths. The reduction in soil erosion was achieved despite the fact that the increase in ground cover under TC grazing had little effect on runoff coefficient or runoff depth. Decrease in runoff in relation to the increase in surface cover only occurred for small events, whereas for large rainfall events, runoff generated irrespective of the level of ground cover. This study showed that ground cover is a key driver in reducing sediment concentration, resulting in a significantly lower sediment loss under TC grazing. In the study area a minimum of 70% of surface cover as a threshold appeared to be needed to efficiently protect the soil surface from erosive forces of rain and runoff and to control soil erosion. The results also indicate that TC grazing has a superior capability to produce and maintain a higher level of ground cover (up to 90%) than continuous grazing (up to 65%). The long rest periods in TC grazing are seen as the major contributor to soil and pasture recovery after intensive defoliations by grazing animals, leading to an increase in above-ground organic material and thus surface cover over time.
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Troccoli, Antonio, Carmen Maddaluno, Massimo Mucci, Mario Russo, and Michele Rinaldi. "Is it appropriate to support the farmers for adopting conservation agriculture? Economic and environmental impact assessment." Italian Journal of Agronomy 10, no. 4 (December 3, 2015): 169. http://dx.doi.org/10.4081/ija.2015.661.
Повний текст джерелаАнотація:
Conservation agriculture (CA) in the last decades has been spread in several parts of the world, especially in South and North America and Australia. In Italy, however, its adoption is often restrained by the risk to have a reduction in crop production in the early years of transition from conventional (CT) to CA. To quantify sufficient financial support to promote no-tillage and CA, a mini-review about main effects of CA was conducted. The effect on crop yield, soil fertility - especially as it is influenced by the chemical, physical and microbiological factors - on soil compaction, the economic balance of the farm and the cost of equipment for direct seeding, the influence of environment on soil erosion, water retention, emissions of greenhouse gases, and carbon sequestration are briefly treated. The paper reports findings from national and international scientific literature and some results from long-term experiments conducted in Southern Italy. The main conclusions are about the reduction of yield in the first years of transition from CT to CA (from -5 to - 10%), an improvement of soil fertility (soil organic carbon increases in the upper layers), reduction of management cost (less machinery operations), improvement of soil C sequestration (in specific conditions), a reduction of greenhouse gases emission and soil erosion risk. The paper provides the scientific basis in order to justify and quantify the amount to be paid to the farmers who decide to adopt the model of CA, oriented to protect the agro-ecosystem and to promote the principle of subsidiarity. Finally, a proposal of public subsidy in cash and for machinery purchase has been described.
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Harper, R. J., and R. J. Gilkes. "The effects of clay and sand additions on the strength of sandy topsoils." Soil Research 42, no. 1 (2004): 39. http://dx.doi.org/10.1071/sr03063.
Повний текст джерелаАнотація:
The clay contents of sandy soils in south-western Australia are often modified, either intentionally or inadvertently, as a result of management practices and erosion. Although the strength of sandy surfaced soils has previously been shown to be related to clay content, in natural soils the effects of induced changes in clay content on soil strength have not been assessed.Increasing amounts of subsoil clay were added to their respective topsoils in increments ranging from 5 to 20% by weight, and these systematically increased soil strength. A strong log–log relationship between clay content and soil strength explained 69% of the variation, with soil strength further affected by sodicity. This enhancement of soil strength has implications for the practice of claying water-repellent soils, particularly where non-uniform application or poor incorporation results in high concentrations of clay, where very high rates (e.g. 300 t/ha) of application are used, or where clayey subsoils are brought to the surface by deep cultivation or the removal of topsoils by erosion.Drift sand, with a clay content of around 1% and negligible strength, was added in increasing increments to typical topsoils, over the range of 0–100% by weight to replicate the effects of wind-induced deposition and winnowing of clay particles. Increasing additions of drift sand systematically decreased soil strength, with a log–log relationship between clay content and strength of the mixtures explaining 81% of the variation. This suggests that wind erosion, and the winnowing of clay or deposition of drift sand, permanently destabilises soil surfaces by reducing soil strength. It is feasible that strategic applications of sand on the surfaces of soils affected by hardsetting may reduce soil strength and encourage soil structure development and seedling emergence.
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Schoknecht, Noel. "Report card on sustainable natural-resource use in the agricultural regions of Western Australia." Soil Research 53, no. 6 (2015): 695. http://dx.doi.org/10.1071/sr14267.
Повний текст джерелаАнотація:
A ‘Report Card’, which summarises the current knowledge of the status and trend in land condition in the agricultural areas of the south-west of Western Australia, was published in 2013 by the Department of Agriculture and Food, Western Australia. The Report Card draws on best available evidence from government and industry on the current condition and trend of 10 soil- and water-related natural resource themes relevant to agriculture, and discusses the implications of these results for the agricultural industries. The report also discusses the three main factors driving the performance of the land, namely climate, land characteristics and land management. The first two factors are largely out of the control of land managers, but in a drying and warming climate of the agricultural areas of Western Australia, land-management practices need to be able to respond to these changing conditions. The paper briefly explains the methodologies used to assess the seven soil-related themes in the Report Card and summarises the major findings. The results indicate that, for soils, the situation and outlook for our natural resources is mixed. Although there has been progress in some areas, such as managing wind and water erosion, the status and trend in many indicators of resource condition, such as soil acidity, soil compaction and water repellence, are adverse. The predicted growth in global demand for food and fibre brings many opportunities to the Western Australian agri-food sector but also challenges, especially in light of the Report Card findings. One of these challenges is our need to achieve agricultural productivity growth while ensuring our natural resources are healthy and resilient.
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Yu, B., C. A. A. Ciesiolka, C. W. Rose, and K. J. Coughlan. "A validation test of WEPP to predict runoff and soil loss from a pineapple farm on a sandy soil in subtropical Queensland, Australia." Soil Research 38, no. 3 (2000): 537. http://dx.doi.org/10.1071/sr99104.
Повний текст джерелаАнотація:
Monthly runoff and soil loss simulated by WEPP (Water Erosion Prediction Project) were compared with field observations on a pineapple farm in south-east Queensland for a 3-year period. The soil at the site is sandy. Slope length and steepness are 36m and 5.5%, respectively. Three treatments, namely bare, farmers’ conventional practice, and mulching of the furrows, were used. Infiltration and erodibility parameters were determined using WEPP-recommended equations and measurable soil properties. These parameters were also calibrated using the runoff and soil loss data for the bare plot only. Apart from the soil loss prediction for the mulching treatment, for which WEPP did not perform well, the average coefficient of efficiency in runoff and soil loss predictions was –0.02 using soil property-based parameter values and 0.66 using calibrated parameter values. The corresponding r 2 values are 0.57 and 0.81, respectively. On the whole, WEPP is able to reproduce the trend and variations in runoff and soil loss among different treatments for the site. Parameter values based on measurable soil properties would greatly under-estimate the runoff and soil loss for the site. Thus, use of WEPP outside its US database requires calibration with locally obtained data. It was also found that WEPP does not seem to model effectively the situation where there is considerable flow impediment with the furrows covered with mulch. We are unable to reject WEPP because the statistical performance indicators are reasonable for the site, and because the model is so complex that it is nearly impossible to pinpoint the source of discrepancy and articulate the model deficiency on physical grounds.
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Ellerton, Daniel, Tammy Rittenour, Graziela Miot da Silva, Allen Gontz, James Shulmeister, Patrick Hesp, Talitha C. Santini, and Kevin J. Welsh. "Late-Holocene cliff-top blowout activation and evolution in the Cooloola Sand Mass, south-east Queensland, Australia." Holocene 28, no. 11 (August 6, 2018): 1697–711. http://dx.doi.org/10.1177/0959683618788679.
Повний текст джерелаАнотація:
Cliff-top dunes are a locally important geomorphic features of sedimentary coasts. They are traditionally interpreted as being sourced by (or with) sand derived from the beach below the cliff. This paper presents the results of a stratigraphic and geochronological study of Carlo Sand Blow, a coastal blowout that has developed on top of a high sandy cliff in the Cooloola Sand Mass, south-east Queensland. We use a combination of sedimentological, pedological and geophysical techniques along with optically stimulated luminescence dating to determine the depositional history and evolution of the blowout. We demonstrate that the blowout is dominantly nourished by sand eroded from its floor rather than the adjacent beach. The original dune surface dates to the first half of the last glacial period (c. 40–70 ka) and this dune was deflated in the late-Holocene. Dune activity is directly associated with cliff undercutting because of coastal retreat in the late-Holocene, but coastal erosion on its own is not capable of maintaining aeolian activity. Blowout activity occurred between 2.6 and 2.3 ka and again at 0.3 ka with aeolian sand burying palaeosols. Both soil surfaces contained charcoal and tree stumps in growth position and our study suggests that fire is the immediate trigger for blowout reactivation. It is likely that these fires were anthropogenic in origin, because the site is somewhat protected from natural fire and the ages coincide with intensification of human use of coastal sites in the area.
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Krause, A. K., R. J. Loughran, and J. D. Kalma. "The use of Caesium-137 to Assess Surface Soil Erosion Status in a Water-Supply Catchment in the Hunter Valley, New South Wales, Australia." Australian Geographical Studies 41, no. 1 (March 2003): 73–84. http://dx.doi.org/10.1111/1467-8470.00193.
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Martinez, C., G. R. Hancock, and J. D. Kalma. "Comparison of fallout radionuclide (caesium-137) and modelling approaches for the assessment of soil erosion rates for an uncultivated site in south-eastern Australia." Geoderma 151, no. 3-4 (July 2009): 128–40. http://dx.doi.org/10.1016/j.geoderma.2009.03.023.
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Costantini, A., and R. J. Loch. "Effects of site preparation on runoff, erosion, and nutrient losses from Pinus plantations established on the coastal lowlands of south-east Queensland, Australia." Soil Research 40, no. 8 (2002): 1287. http://dx.doi.org/10.1071/sr02032.
Повний текст джерелаАнотація:
Site preparation practices used during establishment of second rotation Pinus plantations on the coastal lowlands of south-east Queensland became more conservative during the 1990s. Traditionally, site preparation included stick raking of residue into windrows, followed by burning. Areas subject to periodic saturation were then cultivated to form continuous high mounds, while better drained sites were contour strip cultivated. These practices were replaced by retention of residue biomass on hillslopes. Similarly, intensive site disturbance was increasingly replaced by tillage of the immediate planting zone only and, as far as possible, avoidance of continuous furrows, major drainage structures, and high mounding works. In the study reported here, simulated rainfall and overland flows were used to assess the impacts of the earlier, less-conservative site preparation practices on hillslope soil loss, nutrient loss, and the potential for off-site nutrient movement.Where residue from clearfell harvesting of the first rotation was not removed, runoff, erosion, and nutrient loss were negligible. Harvesting tended to distribute residue widely across hillslopes, and, together with naturally occurring understorey biomass, it formed a largely continuous groundcover. Highest concentrations of sediment in overland flow were recorded for hillslopes in the newly stick-raked condition. Sediment concentrations in overland flows applied to properly designed and constructed high mounds were low, even for large flows simulating relatively long furrow lengths. However, sediment in rainfall-induced runoff from mounded areas was observed to be nutrient enriched, indicating potential for an off-site nutrient pollution risk, at least prior to establishment of grass cover along furrows. Nutrient enrichment was correlated with enrichment of finer size classes of sediment in runoff.The work reported in this paper vindicated the move away from traditional residue removal and site preparation practices to an approach based on residue retention, minimum site disturbance, and, wherever possible, spot rather than continuous mounding/cultivation.
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Blackwell, Paul, Evelyn Krull, Greg Butler, Allan Herbert, and Zakaria Solaiman. "Effect of banded biochar on dryland wheat production and fertiliser use in south-western Australia: an agronomic and economic perspective." Soil Research 48, no. 7 (2010): 531. http://dx.doi.org/10.1071/sr10014.
Повний текст джерелаАнотація:
Effects of banded biochar application on dryland wheat production and fertiliser use in 4 experiments in Western Australia and South Australia suggest that biochar has the potential to reduce fertiliser requirement while crop productivity is maintained, and biochar additions can increase crop yields at lower rates of fertiliser use. Banding was used to minimise wind erosion risk and place biochar close to crop roots. The biochars/metallurgical chars used in this study were made at relatively high temperatures from woody materials, forming stable, low-nutrient chars. The results suggest that a low biochar application rate (~1 t/ha) by banding may provide significant positive effects on yield and fertiliser requirement. Benefits are likely to result from improved crop nutrient and water uptake and crop water supply from increased arbuscular mycorrhizal fungal colonisation during dry seasons and in low P soils, rather than through direct nutrient or water supply from biochars. Financial analysis using farm cash flow over 12 years suggests that a break-even total cost of initial biochar use can range from AU$40 to 190/ha if the benefits decline linearly to nil over 12 years, taking into account a P fertiliser saving of 50% or a yield increase of 10%, or both, assuming long-term soil fertility is not compromised. Accreditation of biochar for carbon trading may assist cost reduction.
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Connolly, R. D., A. Costantini, R. J. Loch, and R. Garthe. "Sediment generation from forest roads: bed and eroded sediment size distributions, and runoff management strategies." Soil Research 37, no. 5 (1999): 947. http://dx.doi.org/10.1071/sr98088.
Повний текст джерелаАнотація:
A rainfall simulator and overland flow study was conducted to determine in situ and eroded sediment size distributions for a range of forest road surfaces at 2 important commercial plantation centres in subtropical south-east Queensland, Australia; and parameters necessary for running the CREAMS model to assess erosion and sediment transport from road/table drain systems. Results revealed very low concentrations of fine particles in the surface of gravel roads, and somewhat higher proportions in ungravelled (dirt) road surfaces. However, there was considerable enrichment of fine particles in sediment eroded under simulated rain, with concentrations of particles <0 . 02 mm in diameter being up to 8 g/L. Table drains were generally resistant to scour by overland flows, with the only exception being a drain bordering a newly gravelled road. This drain was bare of vegetation and contained significant quantities of loose gravel from which the fine component was easily eroded. It demonstrated the need to construct both roads and table drains at the end of the wet season when consolidation and re-vegetation can occur under lighter rains during the dry season. CREAMS model runs for a ‘standard’ road and drain configuration predicted considerable enrichment of fine particles in sediment from all road surfaces. The major factor controlling predicted concentrations of fine particles was the rate of erosion from the road surface, with gravelled surfaces showing considerably less erosion than ungravelled surfaces. Because road surfaces will be significant sources of fine sediment during erosive rains, a second part of this study was designed to model whether hillslopes could be used to infiltrate runoff, thereby controlling sediment movement. For the modelled hillslopes—typical of those used to support commercial forest plantations in south-east Queensland—design runoffs from forest road turn-out drains could be infiltrated. It is suggested that forest managers use hillslope infiltration as the primary tool for managing flows and sediments from road turn-out drains, and that vegetative filter strips be used only as a secondary support tool.
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Anderson, Geoffrey C., Shahab Pathan, James Easton, David J. M. Hall, and Rajesh Sharma. "Short- and Long-Term Effects of Lime and Gypsum Applications on Acid Soils in a Water-Limited Environment: 1. Grain Yield Response and Nutrient Concentration." Agronomy 10, no. 8 (August 18, 2020): 1213. http://dx.doi.org/10.3390/agronomy10081213.
Повний текст джерелаАнотація:
Surface (0–10 cm) and subsoil (soil layers below 10 cm) acidity and resulting aluminum (Al) toxicity reduce crop grain yields. In South Western Australia (SWA), these constraints affect 14.2 million hectares or 53% of the agricultural area. Both lime (L, CaCO3) and gypsum (G, CaSO4) application can decrease the toxic effect of Al, leading to an increase in crop grain yields. Within the region, it is unclear if G alone or the combined use of L and G has a role in alleviating soil acidity in SWA, due to low sulfate S (SO4–S) sorption properties of the soil. We present results from three experiments located in the eastern wheatbelt of SWA, which examined the short-term (ST, 2 growing seasons), medium-term (MT, 3 growing seasons), and long-term (LT, 7 growing seasons over 10 years) effects of L and G on grain yield and plant nutrient concentrations. Despite the rapid leaching of SO4–S and no self-liming impact, it was profitable to apply G, due to the significant ST grain yield responses. The grain yield response to G developed even following relatively dry years, but declined over time due to SO4–S leaching. At the LT experimental site had received no previous L application, whereas, at the ST and MT sites, L had been applied by the grower over the previous 5–10 years. For the LT site, the most profitable treatment for wheat (Triticum aestivum L.) grain yield, was the combined application of 4 t L ha−1 with 2 t G ha−1. At this site, the 0–10 cm soil pHCaCl2 was 4.6, and AlCaCl2 was greater than 2.5 mg kg−1 in the 10–30 cm soil layer. In contrast, at the ST and MT sites, the pHCaCl2 of 0–10 cm soil layer was ≥5.5; it was only profitable to apply G to the MT site where the soil compaction constraint had been removed by deep ripping. The use of L increases soil pHCaCl2, resulting in the improved availability of anions, phosphorus (P) in the LT and molybdenum (Mo) at all sampling times, but reduced availability of cations zinc (Zn) in the LT and manganese (Mn) at all sampling. The application of G reduced Mo concentrations, due to the high SO4–S content of the soil.
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McDowall, M. M., D. J. M. Hall, D. A. Johnson, J. Bowyer, and P. Spicer. "Kikuyu and annual pasture: a characterisation of a productive and sustainable beef production system on the South Coast of Western Australia." Australian Journal of Experimental Agriculture 43, no. 8 (2003): 769. http://dx.doi.org/10.1071/ea02230.
Повний текст джерелаАнотація:
Production parameters and water use of kikuyu (Pennisetum clandestinum) and annual-based pastures were monitored for a beef weaner production system from 1998 to 2000 in a paddock-scale demonstration on the south-east coast of Western Australia. A paired paddock (40–105 ha) comparison was carried out between a kikuyu-based pasture (DSKikuyu) and temperate annual pasture (DSAnnual), with comparative measurements covering pasture production, composition and quality, and soil water deficits and drainage. The stocking rates for the paddocks were determined by the pasture productivity and cow P8 fat depth in the 'lactation phase' (April–December), and by sward management and soil stability imperatives in the 'dry cow phase' (January–March). Cow liveweight and P8 fat depth and calf liveweight were compared during the 'lactation phase'. Kikuyu and annual pasture had similar carrying capacities through the 'lactation phase'. Kikuyu pasture carried more animals than annual pasture through the 'dry cow phase' (late summer and autumn) in all years. During late autumn, cattle were destocked from the annual pasture to reduce the risk of wind erosion and 'crash grazed' on the kikuyu pasture so as to reduce competition between kikuyu and regenerating annual grass and legume species. The comparative quality and productivity of the kikuyu pasture in the lactation phase (winter and spring) was positively correlated with the level of winter legume present. When a similar level of winter legume was measured in the kikuyu pasture relative to the annual pasture (in 1998), the pasture quality, cow liveweight and condition and calf weaning weights were all comparable between the 2 pasture types. When a low legume component was recorded in the kikuyu pasture, the pasture quality and cow liveweight and condition were poorer than the annual pasture. The kikuyu pasture growing on deep sandy soil developed a larger (mean 37 mm) soil water deficit than the annual pasture over the measurement period, and in particular from November to March. When integrated over a farm where kikuyu covers 40% of the total area, as was the case in this experiment, the resulting deep drainage was calculated to be just over half that of an equivalent whole farm of annual pasture. Over the 3 years of monitoring, the combined system of annual and kikuyu pasture was calculated to have an annual gross margin 19% higher than the annual pasture alone. The major source of difference was no requirement for supplementary feed in the kikuyu–annual pasture system. This difference was limited however, by lighter post-weaning sale weights of cull cows from the kikuyu pasture in 'poor legume' years. There was no difference of calf weaning weights between treatments.There is considerable opportunity to improve on this gross margin, through achieving a consistent strong presence of legume in the kikuyu pasture through winter and spring.
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Dekker, Louis W., Klaas Oostindie, and Coen J. Ritsema. "Exponential increase of publications related to soil water repellency." Soil Research 43, no. 3 (2005): 403. http://dx.doi.org/10.1071/sr05007.
Повний текст джерелаАнотація:
Soil water repellency is much more wide-spread than formerly thought. During the last decades, it has been a topic of study for soil scientists and hydrologists in at least 21 States of the USA, in Canada, Australia, New Zealand, Mexico, Colombia, Chile, Congo, Nepal, India, Hong Kong, Taiwan, China, Ecuador, Venezuela, Brazil, Mali, Japan, Israel, Turkey, Egypt, South Africa, Germany, The Netherlands, Spain, Portugal, United Kingdom, Denmark, Sweden, Finland, Poland, Slovakia, Russia, France, Italy, and Greece. Although, water repellent soils already have been indicated at the end of the nineteenth century, they have been discovered and studied in most countries in the last decades. Water repellency is most common in sandy soils with grass cover and in nature reserves, but has also been observed in loam, heavy clay, peat, and volcanic ash soils. From 1940 to 1970 research was focussed on identifying vegetation types responsible for inducing water repellency and on developing techniques to quantify the degree of water repellency. Of special interest has been the effects of wildfire on the development of soil water repellency and its consequences for soil erosion. Due to increasing concern over the threat to surface and groundwater posed by the use of agrichemicals and organic fertilisers, studies on water repellent soils have also been focused on its typical flow behavior with runoff and the existence of preferential flow paths. Since the end of the 1950s, wetting agents and clay amendments have been studied to ameliorate water repellent soils. Since 1883, more than 1200 articles related to soil water repellency have been published in journals, reports, and theses. An exponential increase in number of publications started in 1960, resulting in an average of 200 publications per 5 years.