Journal articles: 'Soil salinization – Western Australia'

1

Hick, PT, and WGR Russell. "Some spectral considerations for remote sensing of soil salinity." Soil Research 28, no. 3 (1990): 417. http://dx.doi.org/10.1071/sr9900417.

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The National Soil Conservation Program (NSCP) and CSIRO funded a research project titled Remote Sensing of Agricultural Salinity, which gathered field and airborne reflectance data for study sites in areas of dryland agricultural salinity in Western Australia. Multivariate techniques are employed to analyse these data gathered over a 3-year period to determine optimum, spectral and temporal considerations for maximizing information content. This report concentrates on some of the spectral aspects and concludes that: spectral bands, existing in currently available remote sensing systems, may not be optimal for the delineation of salinity; that volunteer vegetation indicated the impact of increasing salinity; and that minor amounts of soluble salts in surface soils will modify spectra. The usefulness of portable field spectroradiometers and airborne scanning systems are also assessed for the discrimination of areas of land in the early stages of the effects of salinization.

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Wang, Bo, Xinguang Dong, Zhihui Wang, and Guoqiang Qin. "Characterizing Spatiotemporal Variations of Soil Salinization and Its Relationship with Eco-Hydrological Parameters at the Regional Scale in the Kashi Area of Xinjiang, China from 2000 to 2017." Water 13, no. 8 (April 14, 2021): 1075. http://dx.doi.org/10.3390/w13081075.

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Soil salinization is one of the most serious issues of land degradation, especially in inland drylands, such as the Kashgar region in the Xinjiang province, western China. The investigation of the spatiotemporal variations of soil salinization and its causes is critical for regional ecological restoration and social development. In this study, salinization severity was firstly interpreted in Kashgar region for the years 2000, 2010, and 2017 using multitemporal Landsat images, and the spatiotemporal variations of salinized soil area, salinization severity index, and important index of salinization change were then analyzed using transition matrix method. Finally, the relationship between salinization and eco-hydrological parameters at the regional scale was investigated using correlation analysis and multivariate linear regression. The results show that salinized soil is mainly concentrated in irrigated oasis areas. Although the decrease rate of total salinized soil area is decreasing, the decrease rate of average salinization severity is increasing gradually. There is an increasing trend for the improved area of salinized soil, whereas an opposite trend was observed for the deteriorated area of salinized soil. The conversion from extremely severe salinized soil to the severe ones was the dominant transforming type from 2000 to 2017; meanwhile, the transformation from non-salinized soil to salinized soil for the newly reclaimed farmland was observed, indicating that some necessary irrigation control measures must be taken to avoid further soil salinizing. A significant negative correlation between salinization severity and evapotranspiration, normalized difference vegetation index (NDVI) was observed, implying that soil structure change induced by vegetation, associated with high evapotranspiration (ET) and low land surface temperature (LST), played a positive role in alleviating soil salinization in this region. It is concluded that the soil salinization had been alleviated from 2000 to 2017, mainly due to the combined effects of the farmland expansion and the reasonable irrigation system.

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3

Löffler, Ernst. "Soil erosion and soil salinization in Australia (Érosion et salinisation du sol en Australie)." Bulletin de l'Association de géographes français 69, no. 2 (1992): 161–67. http://dx.doi.org/10.3406/bagf.1992.1624.

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Ive, J. R., P. A. Walker, and K. D. Cocks. "Spatial modelling of dryland salinization potential in Victoria, Australia." Land Degradation and Development 3, no. 1 (April 1992): 27–36. http://dx.doi.org/10.1002/ldr.3400030104.

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5

Zsembeli, József, and Lilla Szűcs. "Environmental friendly irrigation of vegetables with high salt content water." Acta Agraria Debreceniensis, no. 61 (September 18, 2014): 115–19. http://dx.doi.org/10.34101/actaagrar/61/2053.

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Horticultural activities have been characteristic in the hobby gardens located in the northern and western areas around the town of Karcag for more than 300 years. During the droughty summer periods, characteristic to the region, the water demand of vegetables and fruit trees are covered by irrigation, for that the water is gained from drilled wells. These well waters contain high amount of dissolved salts contributing to the secondary salinization of the soil. Taking these facts into consideration an irrigation experiment was set at the lysimeter station of Karcag Research Institute. Our goal was to mitigate the risk of secondary salinization generated by irrigation with waters of high salt content and to survey the application possibilities of soil preserving irrigation.

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6

Dvurechenskya, Elena. "TECHNOGENIC HALOGENESIS IN THE MIDDLE TAIGA OF WESTERN SIBERIA AND EFFECTS OF SOIL SALINIZATION." Acta Geobalcanica 7, no. 3 (October 25, 2020): 101–7. http://dx.doi.org/10.18509/agb.2021.14.

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7

SINGH, B., and R. J. GILKES. "Properties of soil kaolinites from south-western Australia." Journal of Soil Science 43, no. 4 (December 1992): 645–67. http://dx.doi.org/10.1111/j.1365-2389.1992.tb00165.x.

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8

Cochrane, HR, G. Scholz, and AME Vanvreswyk. "Sodic soils in Western Australia." Soil Research 32, no. 3 (1994): 359. http://dx.doi.org/10.1071/sr9940359.

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Sodic soils are common throughout Western Australia, particularly in the south-west agricultural area where they occur mainly as duplex or gradational profiles. Soils with sodic properties are dominant in 26% of the state; saline-sodic sediments and soils in intermittent streams, lakes and estuarine plains occupy a further 5%. Sodic soils are moderately common throughout the south and western portion of the rangeland areas (38% of the state). The south-west coastal sands and the desert and rangeland soils to the north and east of the state are rarely sodic. Although sodicity has been recognized as a discrete problem in W.A. soils since the 1920s, the extent and severity of sodicity has been satisfactorily described only for small areas of the state and most land managers are unaware of the role sodicity plays in limiting the productivity of their soils. Sodicity is implicated in a diversity of problems for both agricultural and non-agricultural uses of Western Australian soils. Subsoil impermeability is probably the most widespread of these, but no comprehensive, quantitative assessment of the influence of exchangeable sodium on subsoil properties has been undertaken. Topsoil sodicity is much less extensive but can severely restrict land productivity, particularly on sandy loam and finer textured soils which set hard when dry. The physical behaviour of Western Australian topsoils cannot usefully be predicted from measurements of exchangeable sodium alone because soils differ so greatly in their response to changing exchangeable sodium. Some remain structurally stable at ESP values >15 while others are so 'sodium-sensitive' that they exhibit highly dispersive behaviour at ESP values as low as 2%. Land values over much of the dryland farming and pastoral areas of W.A. do not justify sustained use of amendments which would reduce soil exchangeable sodium contents. Efficient management of sodic soils in these areas must rely on the prevention of degradation and the use of biological and physical means to maintain adequate soil physical properties. Effective restoration of degraded sodic soils, however, often does require application of inorganic amendments in combination with tillage to initiate structural recovery. Sodicity is currently not considered to be a problem at any of the three main irrigation areas in W.A., but all have sodic soil within their potentially irrigable lands, which may limit their future expansion.

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9

Dvurechenskaya, Elena B. "HALOGENESIS IN OLIGOTROPHIC SOILS OF THE MIDDLE TAIGA OF WESTERN SIBERIA." Географический вестник = Geographical bulletin, no. 3(54) (2020): 148–58. http://dx.doi.org/10.17072/2079-7877-2020-3-148-158.

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The paper provides analysis of salinization processes in the soils of middle taiga due to oil and petroleum products pollution of humid landscapes of Western Siberia. The specific features of man-made chloride-sodium halogenesis which develops in hydromorphic soils of Western Siberia have been investigated. The obtained materials have been initially processed: salt content, alkaline-acid characteristics, soil absorbent complex composition, and organic carbon content have been determined. There have been identified differences in lateral and radial migration of salts in peat bog soils of ryam and ridge-hollow bogs.

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Hart, R. D., T. G. St Pierre, R. J. Gilkes, A. J. McKinley, S. Siradz, and Balwant Singh. "Iron in soil kaolins from Indonesia and Western Australia." Clay Minerals 37, no. 4 (December 2002): 671–85. http://dx.doi.org/10.1180/0009855023740069.

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AbstractSoil kaolins from Indonesia and Western Australia and a range of reference kaolins were studied using Mössbauer spectroscopy, electron paramagnetic resonance (EPR) spectroscopy and SQUID magnetometry. Mössbauer spectra indicate that the Fe within the kaolins is in the highspin Fe3+oxidation state and that a large fraction of the Fe is present as dispersed atoms residing within the octahedral sites of the kaolinite crystal structure. The EPR spectra are typical for soil kaolins except for the absence of radiation-induced defects for the Indonesian kaolins. The Fe(I)spectra are dominant with a strong symmetric peak atg= 4.3, the presence of Fe(II) spectra is shown by a shoulder on this peak atg= 4.9 and a small phase up peak atg= 9.2.Low-temperature (5 K) magnetization (M) measurements over large field (H) sweeps (±70 kOe) yieldedM(H) curves which are fitted well with Brillouin functions indicating the paramagnetic nature of the kaolins at temperatures down to 5 K. A very small remanent magnetization was detectable in the kaolins. Remanent magnetization to saturation magnetization ratios ranged from 10–4to 10–3for the Indonesian kaolins and were all ∼10–3for the Western Australian kaolins, indicating that at high fields the vast majority of the magnetization of the kaolins is due to paramagnetic ions.Zero-field-cooled and field-cooled magnetization measurements in small fields (500 Oe) indicate that the Indonesian kaolins are generally free from magnetically-blocked material down to a temperature of 5 K. The magnetic susceptibility of the Indonesian kaolins shows Curie Law behaviour indicating paramagnetic behaviour over all temperatures down to 5 K. Measurements on the Western Australian kaolins indicated the presence of some magnetic material that is magnetically blocked at temperatures below ∼200 250 K. As a consequence, the magnetic susceptibility showed large deviations from Curie Law behaviour.

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11

St. Pierre, Tim G. "Mössbauer Spectra of Soil Kaolins from South-Western Australia." Clays and Clay Minerals 40, no. 3 (1992): 341–46. http://dx.doi.org/10.1346/ccmn.1992.0400315.

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12

CROWLEY, GABRIEL M. "Groundwater rise, soil salinization and the decline of Casuarina in southeastern Australia during the late Quaternary." Austral Ecology 19, no. 4 (December 1994): 417–24. http://dx.doi.org/10.1111/j.1442-9993.1994.tb00507.x.

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13

Gning, Abdoul, Philippe Orban, Raymond Malou, Joost Wellens, Johan Derouane, Mansour Gueye, and Serge Brouyère. "Impacts of Irrigation Water on the Hydrodynamics and Saline Behavior of the Shallow Alluvial Aquifer in the Senegal River Delta." Water 13, no. 3 (January 27, 2021): 311. http://dx.doi.org/10.3390/w13030311.

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The Senegal River Delta located in north-western Senegal is a strategic region for the development of irrigated rice cultivation for achieving rice self-sufficiency. The presence of a shallow salty water table is often considered as a brake to the development of irrigation, by causing salinization of the soil, although the mechanisms of operation are not well known. An experimental study was carried out in a rice paddy located in the village of Ndiaye, 35 km north from Saint Louis, to characterize the water and solute flux processes below the irrigated plots. The objective was to better understand the irrigation-driven dynamics of soil salinization processes. An experimental monitoring network was installed for monitoring the transit of water at the plot level, in the unsaturated zone and in the aquifer. The results show that the supply of water by irrigation contributes to significantly recharging the water table, as shown by the rise in piezometric level, with a concomitant dilution of the water salinity in the soil zone and in the shallow groundwater. However, when irrigation is stopped, the groundwater level and salinity return within a month to their initial level and salinity status because of the evaporative recovery, which strongly governs these processes. Thus, water flow and solute transfers operate in the delta following a recharge–discharge and dilution–concentration cycle controlled by the water balance, and we do not expect to observe in the short- to middle-term any significant reduction in soil salinization processes by drainage.

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14

Yevgrashkina, Galina, Mykola Kharytonov, Iryna Klimkina, and Elena Shikula. "Long-term assessment, modeling and forecast of salinity conditions of reclaimed mine dumps of Western Donbass." E3S Web of Conferences 280 (2021): 06007. http://dx.doi.org/10.1051/e3sconf/202128006007.

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The neutralization of toxic mine rocks with additional of soil and loess like loam mass leads to a significant decreasing of salts migration at the contact zone. The mathematical model was working out follow general principle where mine rock is pollution source, but soil and loess like loam take place as volumetric filter for water-soluble salts. MathCAD file with commands for solving the problem forecasting the process of vertical salinization of reclaimed minelands was developed. The prospect for the numerical model using up to the most accepted range of values with experimental data shown. The irrigation of reclaimed minelands in the Western Donbass possible in the case of the dilution of the mine waters of aquifers with the Samara river water.

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15

Hamblin, Ann, D. Tennant, and M. W. Perry. "Management of soil water for wheat production in Western Australia." Soil Use and Management 3, no. 2 (June 1987): 63–69. http://dx.doi.org/10.1111/j.1475-2743.1987.tb00712.x.

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16

Hart, Robert D., Robert J. Gilkes, Syamsul Siradz, and Balwant Singh. "The Nature of Soil Kaolins from Indonesia and Western Australia." Clays and Clay Minerals 50, no. 2 (April 1, 2002): 198–207. http://dx.doi.org/10.1346/000986002760832793.

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17

FOULDS, W. "Nutrient concentrations of foliage and soil in South-western Australia." New Phytologist 125, no. 3 (November 1993): 529–46. http://dx.doi.org/10.1111/j.1469-8137.1993.tb03901.x.

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18

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.

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19

Riley, I. T., and S. J. Kelly. "Endoparasitic nematodes in cropping soils of Western Australia." Australian Journal of Experimental Agriculture 42, no. 1 (2002): 49. http://dx.doi.org/10.1071/ea01054.

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Soil samples were collected in Western Australia from cereal fields at about harvest time to determine levels of the endoparasitic nematodes, Pratylenchus and Heterodera. A systematic survey in 1997 and 1998 centred on the 40 shires with the highest proportion of cereal cropping. One hundred and eighty samples were collected in 1997 and 227 in 1998 at 10-km intervals along north–south transects 35 km apart. A targeted survey in 1997 included 98 soil samples from fields selected by growers as having poor productivity without an evident cause. No Heterodera cysts were found in any survey sample but these could be extracted from soils previously known to be infested. Pratylenchus neglectus was most commonly detected followed by P. thornei and P. zeae. Populations identified as P. brachyurus, P. penetrans, P. scribneri, and an undescribed species similar to P. thornei were also found. Overall Pratylenchus was extracted from 63% of samples (mean 1.1, median 0.3, max. 22.0/mL of soil). Maps of the data indicate that Pratylenchus populations were aggregated with some areas having relatively light infestations. There was a positive relationship with the intensity of cereal cropping and a negative relationship with pulse cropping. The findings indicate that potentially damaging Pratylenchus numbers occur in a significant proportion of fields and highlight the need to develop and implement strategies to lower population densities.

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20

Hamza, M. A., and W. K. Anderson. "Improving soil physical fertility and crop yield on a clay soil in Western Australia." Australian Journal of Agricultural Research 53, no. 5 (2002): 615. http://dx.doi.org/10.1071/ar01099.

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In the low rainfall area of Western Australia, clay soils with massive soil structure form a major part of the area sown to wheat. Yield increases on such soils have been poor in the last decade compared with those on other soil types. An experiment was conducted over 4 years (1997–2000) using a factorial combination of soil ripping to 0.4 m, application of commercial grade gypsum at 2.5 t/ha, and addition of complete nutrients based on soil test each year. All crop residues were retained after harvest and returned to the soil. The experiment was conducted in a wheat–field pea rotation at Merredin, WA. Soil water infiltration rate, soil strength, bulk density, water-stable aggregates, cation exchange capacity, and wheat yields were measured. Grain yields of wheat and field peas were increased by deep ripping, the addition of gypsum, or the addition of complete nutrients in some years. The main treatment effects on yield were additive, as significant interactions between the treatments on yield were seldom found. However, all the main treatments also significantly improved many of the soil physical properties related to crop growth. In 2000, 4 years after the treatments were applied, soil water infiltration rate was increased by more than 200%, strength of the topsoil decreased by around 1600 kPa, and soil bulk density decreased by 20%. Gypsum application increased water-stable aggregates, but soil mixing caused by deep ripping reduced them. The combination of soil ripping and gypsum application in the presence of complete nutrients and annual return of crop residues to the soil is suggested to improve crop grain yield and soil physical fertility on a range of Western Australian soils.

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21

Daneshmand, Hossein, Sina Alaghmand, Matteo Camporese, Amin Talei, Pat J. F. Yeh, and Edoardo Daly. "Long-Term Impacts of Partial Afforestation on Water and Salt Dynamics of an Intermittent Catchment under Climate Change." Water 12, no. 4 (April 9, 2020): 1067. http://dx.doi.org/10.3390/w12041067.

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Soil salinization is a major environmental issue in arid and semi-arid regions, and has been accelerated in some areas by removal of native vegetation cover. Partial afforestation can be a practical mitigation strategy if efficiently integrated with farms and pastures. Using an integrated surface-subsurface hydrological model, this study evaluates the water and salt dynamics and soil salinization conditions of a rural intermittent catchment in the semi-arid climate of southeast Australia subjected to four different partial afforestation configurations under different climate change scenarios, as predicted by several general circulation models. The results show that the locations of afforested areas can induce a retarding effect in the outflow of groundwater salt, with tree planting at lower elevations showing the steadier salt depletion rates. Moreover, except for the configuration with trees planted near the outlet of the catchment, the streamflow is maintained under all other configurations. It appears that under both Representative Concentration Pathways considered (RCP 4.5 and RCP 8.5), the Hadley Centre Global Environmental Model represents the fastest salt export scheme, whereas the Canadian Earth System Model and the Model for Interdisciplinary Research on Climate represent the slowest salt export scheme. Overall, it is found that the location of partial afforestation generally plays a more significant role than the climate change scenarios.

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22

Farré, Imma, Michael Robertson, and Senthold Asseng. "Reliability of canola production in different rainfall zones of Western Australia." Australian Journal of Agricultural Research 58, no. 4 (2007): 326. http://dx.doi.org/10.1071/ar06176.

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The area of canola in the wheat-based farming systems of the wheatbelt of Western Australia (WA) expanded rapidly during the 1990s and has subsequently decreased. Due to the short history of canola production in WA, there is little information on yield and oil content expectations in relation to rainfall, location, and soil type. In this paper we: (1) present the recent history of canola production in the context of the long-term climate record; (2) assess the effect of location, rainfall, soil type, and soil water at sowing on yield and oil content; and (3) determine cut-off sowing dates for profitable canola production. Simulations were run using the APSIM-Canola model with long-term climate records for 3 selected locations from the low-, medium-, and high-rainfall zones and different soil types. Analysis of recent trends in canola area showed that poor seasons and price volatility in the last few years have contributed to farmers’ perception of risk and hence the decline in area sown. Long-term simulations showed the importance of location, sowing date, soil type, and stored soil water at sowing on grain yield. Yield was negatively related to sowing date. Light-textured soils had lower yields and larger yield penalties with delayed sowing than heavy-textured soils. Soil water at sowing gave a yield advantage in most years in all locations studied, but especially in low- and medium-rainfall locations. Variation in oil content was most strongly affected by sowing date and location, while soil type and soil water at sowing had a minor effect. Long-term simulation analysis can be used as a tool to establish the latest possible sowing date to achieve profitable canola for different locations and soil types, given different canola prices and growing costs. Given the vulnerability of profitability to seasonal conditions, in the low- and medium-rainfall zone, the decision to grow canola should be tactical depending on stored soil water, sowing opportunities, seasonal climate outlook, prices, and costs. In contrast, in the high-rainfall zone, canola production is relatively low risk, and could become a reliable component of rotations.

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23

Debruyn, LAL, and AJ Conacher. "Soil modification by termites in the central wheat-belt of Western-Australia." Soil Research 33, no. 1 (1995): 179. http://dx.doi.org/10.1071/sr9950179.

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In a semi-arid region of Western Australia, in kwongan and open woodland, we examined the texture and selected chemical properties of two soil types, firstly in the mounds of two mound-building termite species (Drepanotermes tamminensis and Amitermes obeuntis) and secondly in the foraging galleries of D. tamminensis and A. neogermanus. The soil properties of the termite-modified soil were compared with soil unaffected by termite activity. It was found that both mounds and foraging galleries had significantly higher clay contents, increased organic carbon, and lower pH than the surface soil. The mean standing mass of D. tamminensis mounds was 5 Mg ha-1) on yellow sand (under kwongan vegetation) and 7 Mg ha-1) on grey sandy loam (under open woodland). However, this modified soil is predicted to be inaccessible for plant growth for a considerable period of time, since termite mound longevity could be as much as 70 years. In contrast, termite-modified soil from foraging galleries and chambers in the soil or soil sheetings covering food sources would be more readily accessible to the plant-soil ecosystem than modified soil materials in termite mounds.

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24

Pepper, R. G., and G. F. Craig. "Resistance of Selected Eucalptys Species to Soil Salinity in Western Australia." Journal of Applied Ecology 23, no. 3 (December 1986): 977. http://dx.doi.org/10.2307/2403949.

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25

Bastian, L. V. "Residual soil mineralogy and dune subdivision, Swan Coastal Plain, Western Australia." Australian Journal of Earth Sciences 43, no. 1 (February 1996): 31–44. http://dx.doi.org/10.1080/08120099608728233.

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26

Asumadu, K., R. J. Gilkes, H. M. Churchward, and T. M. Armitage. "Detailed characterization of quartz grains in two sandy soils, Western Australia." Geoderma 41, no. 1-2 (December 1987): 29–47. http://dx.doi.org/10.1016/0016-7061(87)90027-9.

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27

Rovira, AD. "Dryland mediterranean farming systems in Australia." Australian Journal of Experimental Agriculture 32, no. 7 (1992): 801. http://dx.doi.org/10.1071/ea9920801.

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The mediterranean region of Australia extends from Geraldton in Western Australia across southern Australia into western and northern Victoria. This region experiences hot, dry summers and cool, wet winters, with 300-600 mm annual rainfall. In the dryland farming zone, the cereal-livestock farming system dominates and produces 30-35% of Australia's total agricultural production. The major soils in the region are deep, coarse-textured sands and sandy loams, duplex soils with coarse-textured sands over clay (generally low in nutrients and organic matter), and fine-textured red-brown earths of low hydraulic conductivity. Major soil problems in the region include sodicity, salinity, soil structural degradation, nutrient deficiencies, boron toxicity, acidity, waterlogging, inadequate nitrogen nutrition, water-repellence, and root diseases. These problems have been exacerbated by excessive clearing of trees, increased frequency of cropping, reduced area sown to pastures, declining pasture production, and a decline in nutrient levels. With improved soil management there is potential for increased productivity from dryland farming areas of the region and improved ecological sustainability.

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Wong, DH, MJ Barbetti, and K. Sivasithamparam. "Behavior of Phytophthora clandestina propagules at a field site in Western Australia." Soil Research 24, no. 4 (1986): 485. http://dx.doi.org/10.1071/sr9860485.

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The number of infective propagules of Phytophthora clandestina, an important pathogen of subterranean clover, was estimated by the most probable number (MPN) method in soil at a field site in Western Australia. The behaviour of the propagules of this fungus was studied in relation to root disease index (RDI), disease suppressiveness index (DSI), rainfall, soil moisture and soil temperature for a period of 12 months. There was an increase in the number of infective propagules in the field soil in January and no further increase was observed until May, then marked decrease occurred in June and July with the numbers remaining low through to December. There was no significant correlation between MPN and RDI, DSI, rainfall, soil moisture or temperature. The RDI was, however, negatively correlated (P < 0.05) with DSI linearly (r = 0.76) and quadratically (r = 0.81). Subterranean clover appears to be the sole source of P. clandestina inoculum in the pasture sward of mixed plant species.

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Mcfarlane, DJ, RJ Loughran, and BL Campbell. "Soil erosion of agricultural land in Western Australia estimated by cesium-137." Soil Research 30, no. 4 (1992): 533. http://dx.doi.org/10.1071/sr9920533.

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The caesium-137 technique was used to estimate net soil loss from 10 hillslopes in the agricultural area of Western Australia. The gravel fraction of the soil was found to have approximately 56% of the total 137Cs activity found on the <2 mm fraction of the soil on three slopes where it was measured. In the lower rainfall zones, 137Cs appeared not to have uniformly labelled the soils in uncleared areas, possibly due to the redistribution of rainfall in the canopy and above the soil surface, and the water repellence of some soils. A previously established calibration curve was used to calculate net soil losses from the 10 hillslopes. Potato-growing land and slopes below rock outcrops in the Wheatbelt appear to have experienced the most severe erosion since the soils were first labelled with 137Cs in the mid 1950s (19-27 t ha-1 yr-1). Hillslopes below rock outcrops had appreciably less 137Cs than those below lateritic breakaways, indicating the presence of sheet erosion.

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Barrett-Lennard, Edward G., Geoffrey C. Anderson, Karen W. Holmes, and Aidan Sinnott. "High soil sodicity and alkalinity cause transient salinity in south-western Australia." Soil Research 54, no. 4 (2016): 407. http://dx.doi.org/10.1071/sr15052.

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Transient salinity associated with increased dispersion of clays is arguably one of the most economically important soil constraints in Australia because it occurs on land that is regularly cropped. However, this issue is rarely studied. This paper examines the occurrence of transient salinity on agricultural land in the south-west of Western Australia and the factors causing it. We analysed four soil datasets from the region, collected at scales varying from the entire south-west to a single paddock. A variety of soil parameters were correlated with increased electrical conductivity (EC1:5). The most significant relationships were invariably with measures of exchangeable sodium (Na+; 53–85% of variance accounted for), and this factor appears to be most responsible for transient salinity. Another parameter correlated with increased EC1:5 was alkalinity. This has been associated with the increased dispersion of kaolinite and consequent decreases in soil hydraulic conductivity; kaolinite is the most common clay mineral in the south-west of Western Australia. Other factors correlated with increased EC1:5 were increasing clay, increasing depth in the soil profile and decreasing rainfall. These factors are environmental indicators of transient salinity. Affected soils might be ameliorated by application of agents to increase soil hydraulic conductivity, such as gypsum and/or elemental sulfur.

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Qi, Zhiwei, Changlai Xiao, Ge Wang, and Xiujuan Liang. "Study on Ecological Threshold of Groundwater in Typical Salinization Area of Qian’an County." Water 13, no. 6 (March 20, 2021): 856. http://dx.doi.org/10.3390/w13060856.

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A suitable groundwater level is an important condition to maintain the stability of the vegetation community, especially in arid and semi-arid areas. The surface of Qian’an County in Western Jilin Province is often accompanied by salinization due to the influence of natural and human factors. In order to maintain the healthy development of ecological vegetation and reduce the risk of soil salinization, the concept of an ecological threshold of groundwater level is proposed, and two methods are used to determine the reasonable ecological threshold of groundwater. (1) Based on field investigation and indoor experiment, the data layer of soil texture, land use type and groundwater mineralization degree in the research area was established by using remote sensing technology and GIS technology. According to the thickness of vegetation root layer and the height of capillary rise of different soil and water types, the influence of groundwater salinity is considered, and the sum of the two is taken as the ecological threshold of groundwater in the study area. The reasonable threshold value of suitable growth of various vegetation crops is 3.76~5.66 m. (2) According to the relationship between the normalized vegetation index (NDVI) and the groundwater buried depth and phreatic salt, the groundwater buried depth and the mineralization degree under the best vegetation cover are analyzed as follows: the buried depth of groundwater is between 4.8 m and 6.1 m, and the salinity of groundwater is between 0.37 and 1.25 g/L, which are reasonable groundwater properties in the study area of the ecological threshold. This result not only enriches and broadens the content of groundwater research, but also helps to predict the prospect of water resource development.

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Sprigg, Hayden, Robert Belford, Steve Milroy, Sarita Jane Bennett, and David Bowran. "Adaptations for growing wheat in the drying climate of Western Australia." Crop and Pasture Science 65, no. 7 (2014): 627. http://dx.doi.org/10.1071/cp13352.

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This study investigated the effects of predicted changes in rainfall distribution in marginal (≤325 mm annual rainfall) parts of the south-west Australian wheatbelt and options for management and adaptation of the wheat crop. Field experiments with rain-out shelters and irrigation were conducted in 2008 and 2009 to investigate the interactions of rainfall distribution, row spacing, genotype and timing of nitrogen application on growth, water use and grain yield of spring wheat. Water storage before seeding showed potential to maintain or increase yields despite lower in-season rainfall. Widening row spacing reduced biomass and slowed water use but did not increase grain yield, because of increased soil evaporation and water left in the soil at crop maturity. The Agricultural Production Systems Simulator (APSIM) wheat model was used to investigate the effects of recent and projected climate change on yield in relation to row spacing, phenology and nitrogen. Two climate-change scenarios were applied to historical climatic data to create two plausible future climates (‘optimistic’ and ‘pessimistic’) for the year 2030. None of the strategies tested increased wheat yield under the predicted climate scenarios. Simulated yields at wider row spacings were consistently lower due to insufficient biomass, increased soil evaporation and the inability of the crop to use all of the available water before maturity. Simulated yields of short-season genotypes were always greater than yields of longer season genotypes. Nitrogen regimes had little effect in this study. This study points to several genotypic traits that could improve the performance of wheat grown at wider row spacings. These include early vigour to reduce soil evaporation and increase competition with weeds, greater tillering/biomass to reduce limitation by sink size, and a vigorous root system with appropriate lateral spread and growth to depth to access available soil water.

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Standish, Rachel J., and Richard J. Hobbs. "Restoration of OCBILs in south-western Australia: Response to Hopper." Plant and Soil 330, no. 1-2 (October 9, 2009): 15–18. http://dx.doi.org/10.1007/s11104-009-0182-z.

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Li, Y., E. P. Campbell, D. Haswell, R. J. Sneeuwjagt, and W. N. Venables. "Statistical forecasting of soil dryness index in the southwest of Western Australia." Forest Ecology and Management 183, no. 1-3 (September 2003): 147–57. http://dx.doi.org/10.1016/s0378-1127(03)00103-8.

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VLAHOS, STEPHEN, and DAVID T. BELL. "Soil seed-bank components of the northern jarrah forest of Western Australia." Austral Ecology 11, no. 2 (June 1986): 171–79. http://dx.doi.org/10.1111/j.1442-9993.1986.tb01388.x.

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36

Lau, I., and M. Verrall. "Acid sulphate soil mapping with hyperspectral imagery at South Yunderup, Western Australia." ASEG Extended Abstracts 2009, no. 1 (2009): 1. http://dx.doi.org/10.1071/aseg2009ab100.

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Shi, Xian-Zhong, Mehrooz Aspandiar, and David Oldmeadow. "Reflectance spectral characterization of acid sulphate soil in South Yunderup, Western Australia." International Journal of Remote Sensing 35, no. 10 (April 24, 2014): 3537–55. http://dx.doi.org/10.1080/01431161.2014.907938.

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Lee, Joanna, Armin Postmaster, Hooi Peng Soon, David Keast, and Kerry C. Carson. "Siderophore production by actinomycetes isolates from two soil sites in Western Australia." BioMetals 25, no. 2 (October 29, 2011): 285–96. http://dx.doi.org/10.1007/s10534-011-9503-9.

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39

Gardner, WK, RG Fawcett, GR Steed, JE Pratley, DM Whitfield, Hvan Rees, and Rees H. Van. "Crop production on duplex soils in south-eastern Australia." Australian Journal of Experimental Agriculture 32, no. 7 (1992): 915. http://dx.doi.org/10.1071/ea9920915.

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The environment, duplex soil types and trends in crop production in South Australia, southern New South Wales, north-eastern and north-central Victoria, the southern Wimmera and the Victorian Western District are reviewed. In the latter 2 regions, pastoral industries dominate and crop production is curtailed by regular and severe soil waterlogging, except for limited areas of lower rainfall. Subsurface drainage can eliminate waterlogging, but is feasible only for the Western District where subsoils are sufficiently stable. The other regions all have a long history of soil degradation due to cropping practices, but these effects can now be minimised with the use of direct drilling and stubble retention cropping methods. A vigorous pasture ley phase is still considered necessary to maintain nitrogen levels and to restore soil structure to adequate levels for sustainable farming. Future productivity improvements will require increased root growth in the subsoils. Deep ripping, 'slotting' of gypsum, and crop species capable of opening up subsoils are techniques which may hold promise in this regard. The inclusion of lucerne, a perennial species, in annual pastures and intercropping at intervals is a technique being pioneered in north-central and western Victoria and may provide the best opportunity to crop duplex soils successfully without associated land degradation.

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Asseng, S., B. A. Keating, I. R. P. Fillery, P. J. Gregory, J. W. Bowden, N. C. Turner, J. A. Palta, and D. G. Abrecht. "Performance of the APSIM-wheat model in Western Australia." Field Crops Research 57, no. 2 (May 1998): 163–79. http://dx.doi.org/10.1016/s0378-4290(97)00117-2.

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Rokich, Deanna P., Kathy A. Meney, Kingsley W. Dixon, and K. Sivasithamparam. "The impact of soil disturbance on root development in woodland communities in Western Australia." Australian Journal of Botany 49, no. 2 (2001): 169. http://dx.doi.org/10.1071/bt00015.

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The impact of soil disturbance of the Banksia woodland soil profile and particularly the effect of different reconstructed soil profiles (overburden profile, white profile and yellow profile) and soil ripping within rehabilitation sites, was investigated in terms of root development and architecture for eight species that are key structural elements in Banksia woodland. The aim was to determine the soil environment best suited for root development and architecture likely to contribute to high seedling survival in post-mined sites. Root development and architecture differed significantly between native woodland, and rehabilitation sites. In general, roots were longer in native woodland with low lateral root production (for all species studied) compared to rehabilitation sites where the roots were shorter, tended to divide or lose geotrophy and consisted of numerous laterals. When comparing the different soil profiles in the rehabilitation sites, the commonly reconstructed profile of ‘topsoil over overburden’ (overburden profile) was the least favourable for root development and architecture. Ripping of the soil to 80 cm depth had a positive effect on root growth. There were differences between native woodland and rehabilitation sites, in soil impedance, soil bulk density, soil moisture percentage and organic carbon content. In general, reconstructed soils in rehabilitation sites have (1) soil impedance and soil bulk density values likely to seriously impede root development and architecture, (2) soil moisture percentages higher than those in undisturbed woodland during all months of monitoring and at most depths down to 40 cm and (3) lower organic carbon content than native woodland. When comparing the different soil profiles in rehabilitation sites, the overburden profile (a) had the highest impedance values, (b) was one of the profiles with the highest bulk density values and (c) had the highest soil moisture percentages during most months and at most depths examined. Ripping the soil decreased soil impedance and soil moisture contents. The major conclusion from this study is that soil impedance, which influences water movement, is a key characteristic of soil conditions that are not conducive to the development of deep penetrating root systems. These deep root systems may be directly linked to survival.

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Singh, B., and RJ Gilkes. "Phosphorus sorption in relation to soil properties for the major soil types of South-Western Australia." Soil Research 29, no. 5 (1991): 603. http://dx.doi.org/10.1071/sr9910603.

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The P sorption characteristics of 97 soils that are representative of the agricultural areas of Western Australia were described using Langmuir and Freundlich equations. The Langmuir P maximum (xm) ranged from 11 to 2132 �g g-1 soil and the Freundlich k coefficient ranged from 1 to 1681. Clay content, DCB Fe and Al, oxalate Fe and AL, and pyrophosphate Al were positively related to xm and k. By using stepwise regression analysis, the combination of DCB and oxalate-soluble A1 predicted more than 75% Of the variation in the P sorption coefficients. Reactive Al compounds may thus be responsible for much of the P sorption by these soils. Soil pH in 1 M NaF (pH 8.2), which is normally used for the detection of allophanic material, was strongly related to the P sorption coefficients and might therefore be used as a quick test for predicting the P sorption capacity of soils.

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Noble, R. R. P., D. M. Seneshen, M. J. Lintern, R. R. Anand, A. Pagès, and G. T. Pinchand. "Soil-gas and weak partial soil extractions for nickel exploration through transported cover in Western Australia." Geochemistry: Exploration, Environment, Analysis 18, no. 1 (August 8, 2017): 31–45. http://dx.doi.org/10.1144/geochem2017-026.

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Aldaoud, R., W. Guppy, L. Callinan, S. F. Flett, K. A. Wratten, G. A. Murray, T. Cook, and A. McAllister. "Occurrence of Phytophthora clandestina in Trifolium subterraneum paddocks in Australia." Australian Journal of Experimental Agriculture 41, no. 2 (2001): 187. http://dx.doi.org/10.1071/ea00048.

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In 1995–96, a survey of soil samples from subterranean clover (Trifolium subterraneum L.) paddocks was conducted across Victoria, South Australia, New South Wales and Western Australia, to determine the distribution and the prevalence of races of Phytophthora clandestina (as determined by the development of root rot on differential cultivars), and the association of its occurrence with paddock variables. In all states, there was a weak but significant association between P. clandestina detected in soil samples and subsequent root rot susceptibility of differential cultivars grown in these soil samples. Phytophthora clandestina was found in 38% of the sampled sites, with a significantly lower prevalence in South Australia (27%). There were significant positive associations between P. clandestina detection and increased soil salinity (Western Australia), early growth stages of subterranean clover (Victoria), mature subterranean clover (South Australia), recently sown subterranean clover (South Australia), paddocks with higher subterranean clover content (Victoria), where herbicides were not applied (South Australia), irrigation (New South Wales and Victoria), cattle grazing (South Australia and Victoria), early sampling dates (Victoria and New South Wales), sampling shortly after the autumn break or first irrigation (Victoria), shorter soil storage time (Victoria) and farmer’s perception of root rot being present (Victoria and New South Wales). Only 29% of P. clandestina isolates could be classified under the 5 known races. Some of the unknown races were virulent on cv. Seaton Park LF (most resistant) and others were avirulent on cv. Woogenellup (most susceptible). Race 1 was significantly less prevalent in South Australia than Victoria and race 0 was significantly less prevalent in New South Wales than in South Australia and Western Australia. This study revealed extremely wide variation in the virulence of P. clandestina. The potential importance of the results on programs to breed for resistance to root rot are discussed. in South Australia.

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L. Morgan, David, Dean C. Thorburn, and Howard S. Gill. "Salinization of southwestern Western Australian rivers and the implications for the inland fish fauna - the Blackwood River, a case study." Pacific Conservation Biology 9, no. 3 (2003): 161. http://dx.doi.org/10.1071/pc030161.

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Increasing salinities throughout southwestern Western Australia, facilitated by extensive land clearing, have compromised the region's highly endemic freshwater fishes. Salinization of the Blackwood River has resulted in the main channel and upper cleared catchment being dominated by estuarine and halotolerant teleosts. The non-halotolerant species are restricted to the forested non-saline tributaries of the lower catchment. Of the 12 943 fish (13 species) captured in 113 sites, the halotolerant introduced Mosquitofish Gambusia holbrooki was widespread and the most abundant, representing almost 52% of fish caught. The estuarine Western Hardyhead Leptatherina wallacei, which was also widespread throughout the main channel and upper catchment, was the next most abundant, representing ca. 24% of fish caught. Freshwater endemics represented ca. 23% of captures, with the Western Minnow Galaxias occidentalis and Western Pygmy Perch Edelia vittata accounting for most (i.e., ca. 20%). There were significant differences in teleost communities among the naturally vegetated, low salinity tributaries of the river compared with the main channel and upper cleared catchment. While the forested tributaries still contain populations of E. vittata, Nightfish Bostockia porosa and Mud Minnow Galaxiella munda, the elevated salinities in the upper reaches of the Blackwood River system appear to have caused a massive decline in, or extinction of, populations of these species. The protection of the region's unique freshwater teleosts relies on the preservation of their remaining habitat in both the uncleared catchments of the region and in the low salinity forested tributaries within largely cleared systems, such as those in the Blackwood River catchment.

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Dolling, P. J., S. Asseng, M. J. Robertson, and M. A. Ewing. "Water excess under simulated lucerne - wheat phased systems in Western Australia." Australian Journal of Agricultural Research 58, no. 8 (2007): 826. http://dx.doi.org/10.1071/ar06048.

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The long-term effect of lucerne use, in reducing drainage of water below the root zone and runoff (water excess), has not been examined in south-western Australia (Western Australia). The main aims of the paper were to determine how the long-term mean water excess was influenced by the proportion of lucerne in the rotation and the length of the lucerne phase in relation to soil type and location. A simulation model was used to compare scenarios, drawing on historical weather data from 1957 to 2001. Simulations were performed for 2 locations (high and low rainfall) and 2 soil types (high and low water-holding capacity). Lucerne significantly and rapidly (within 2–3 years) reduces the long-term mean water excess in rotations consisting of 2–4 years of lucerne followed by 1–4 years of wheat compared with continuous wheat. For every 10% increase in the percentage of lucerne years in the total rotation length, the mean water excess decreased by 17–20 mm (7–9%) at Kojonup (high-rainfall site) and 7–8 mm (8–9%) at Buntine (low-rainfall site) compared with the water excess associated with continuous wheat at each location. The proportion of lucerne in the rotation had a greater effect on the water excess than the effect of different soil types. Variation in the water excess due to variation in rainfall was greater than the reduction in water excess due to lucerne. This makes the decisions about when to grow lucerne to reduce water excess difficult if livestock enterprises are less profitable than cropping enterprises. The simulations show that lucerne mean yearly biomass ranges from 4.5 to 6.9 t/ha at Kojonup and from 1.6 to 4.7 t/ha at Buntine, depending on soil type and stage of lucerne in the land use sequence. It is worth considering that lucerne has the potential to reduce subsequent wheat yields with removal in autumn.

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Samadi, Abbas, and R. J. Gilkes. "Phosphorus Transformations and Their Relationships with Calcareous Soil Properties of Southern Western Australia." Soil Science Society of America Journal 63, no. 4 (July 1999): 809–15. http://dx.doi.org/10.2136/sssaj1999.634809x.

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48

Hatton, T. J., J. Ruprecht, and R. J. George. "Preclearing hydrology of the Western Australia wheatbelt: Target for the future?" Plant and Soil 257, no. 2 (December 2003): 341–56. http://dx.doi.org/10.1023/a:1027310511299.

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Summers, RN, NR Guise, DD Smirk, and KJ Summers. "Bauxite residue (red mud) improves pasture growth on sandy soils in Western Australia." Soil Research 34, no. 4 (1996): 569. http://dx.doi.org/10.1071/sr9960569.

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Red mud is a finely crushed, iron-rich, alkaline residue, obtained by digesting bauxite with caustic soda to remove the alumina. The remnant alkalinity of red mud is equivalent to 11% pure calcium carbonate. Phosphorus leaching from infertile sandy soils has resulted in eutrophication of estuaries and has caused algal blooms. Red mud has been shown to reduce leaching of phosphorus from sandy soil. This research was undertaken to determine the effect of red mud on pasture growth and uptake of heavy metals. Red mud, either untreated or treated with gypsum, was applied at rates of 0, 10, 20, 40, and 80 t/ha to a subterranean clover and ryegrass hay paddock. There were 3 replicates of each treatment and a completely randomised design was used. The experimental design was 5 rates of red mud x 2 untreated and treated with gypsum x 3 replicates, resulting in 30 plots. Plant growth, and nutrient and heavy metal composition of the plant tops, were measured. An application of 40 t/ha of red mud increased hay (mainly subterranean clover and ryegrass) production by 24% and increased soil pH in the top 10 cm by 1.0 unit from 3.5 (1 : 5 soil : 0.1 M CaCl2). The increase in production was probably because of the liming effect of the remnant alkali in the red mud, which may have potential as a replacement for crushed limestone. Sodium carbonate, the predominant alkali in red mud, is more soluble than calcium carbonate from crushed limestone and has the potential to change the pH of the soil more rapidly. The soil was top-dressed with red mud, without disturbing the existing pasture, resulting in changes to the pasture production and nutrient composition consistent with a change in soil pH throughout the rooting depth. If crushed limestone is not mixed into the soil it may take many years to increase the pH of the soil; however, this mixing results in extra cost from re-seeding and an initial depression in yield. Although much more red mud is needed than lime, the cost is comparable when the haulage distance is less than about 30 km. In previous trials, at red mud application rates > 500 t/ha, gypsum was mixed into the red mud to reduce salinity and pH. At these rates, the red mud had overwhelmed the buffering capacity of the soil. The gypsum reduced the pH by changing the sodium carbonate in the red mud to calcium carbonate, thus changing the pH from > 10 to about 8.5. However, amendment of the red mud with gypsum when applied at rates < 80 t/ha proved unnecessary in this experiment, probably because the proportion of soil was sufficient to alter the pH of the red mud. When red mud is applied to acidic infertile sands, manganese application as manganese sulfate may be necessary, because the rise in pH may rapidly induce manganese deficiency in plants. Care should be taken to monitor other nutrients which have their availability for plants affected by pH (e.g. copper, zinc, and molybdenum). Red mud did not elevate the concentrations of heavy metals in the soil, hay, or fresh plant tissue.

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Holmes, K. W., E. A. Griffin, and N. P. Odgers. "Large-area spatial disaggregation of a mosaic of conventional soil maps: evaluation over Western Australia." Soil Research 53, no. 8 (2015): 865. http://dx.doi.org/10.1071/sr14270.

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Conventional soil maps may be the best available source for spatial soil information in data-limited areas, including individual soil properties. Spatial disaggregation of these maps, or mapping the unmapped soil components, offers potential for transforming them into spatially referenced soil class distributions. We used an automated, iterative classification tree approach to spatially disaggregate a patchwork of soil surveys covering Western Australia (2.5 × 106 km2) to produce raster surfaces of soil class occurrence. The resulting rasters capture the broad spatial patterns of dominant soils and harmonise soil class designations across most survey boundaries. More than 43 000 archived profiles were used to evaluate the accuracy of the rasters. In 20% of cases, the predicted soil class with the highest probability matched that recorded for the profile; when any of the three highest probability soil classes predicted were considered correct, the global accuracy was 40%. The accuracy increased to 71% when the rasters were reassembled to represent a higher level in the soil classification system. The predicted surfaces retained features related to the mapping intensity of the original surveys and generally had higher prediction accuracy of profile soil class where the surface geochemistry was more homogeneous. The best indicator of prediction accuracy was how common the profile soil class was in the original mapping (94% variance explained); profile observations collected during soil survey may be biased towards rare soils, making them less suitable for validation or modelling directly from point data.

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Journal articles on the topic 'Soil salinization – Western Australia'

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