The Experts below are selected from a list of 333432 Experts worldwide ranked by ideXlab platform
Bai Zhang - One of the best experts on this subject based on the ideXlab platform.
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mapping soil salinity Sodicity by using landsat oli imagery and plsr algorithm over semiarid west jilin province china
Sensors, 2018Co-Authors: Hao Yu, Baojia Du, Zongming Wang, Liangjun Hu, Bai ZhangAbstract:Soil salinity and Sodicity can significantly reduce the value and the productivity of affected lands, posing degradation, and threats to sustainable development of natural resources on earth. This research attempted to map soil salinity/Sodicity via disentangling the relationships between Landsat 8 Operational Land Imager (OLI) imagery and in-situ measurements (EC, pH) over the west Jilin of China. We established the retrieval models for soil salinity and Sodicity using Partial Least Square Regression (PLSR). Spatial distribution of the soils that were subjected to hybridized salinity and Sodicity (HSS) was obtained by overlay analysis using maps of soil salinity and Sodicity in geographical information system (GIS) environment. We analyzed the severity and occurring sizes of soil salinity, Sodicity, and HSS with regard to specified soil types and land cover. Results indicated that the models’ accuracy was improved by combining the reflectance bands and spectral indices that were mathematically transformed. Therefore, our results stipulated that the OLI imagery and PLSR method applied to mapping soil salinity and Sodicity in the region. The mapping results revealed that the areas of soil salinity, Sodicity, and HSS were 1.61 × 106 hm2, 1.46 × 106 hm2, and 1.36 × 106 hm2, respectively. Also, the occurring area of moderate and intensive Sodicity was larger than that of salinity. This research may underpin efficiently mapping regional salinity/Sodicity occurrences, understanding the linkages between spectral reflectance and ground measurements of soil salinity and Sodicity, and provide tools for soil salinity monitoring and the sustainable utilization of land resources.
William F. Bleam - One of the best experts on this subject based on the ideXlab platform.
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atterberg limits and shrink swell capacity of soil as indicators for sodium sensitivity within a gradient of soil exchangeable sodium percentage and salinity
Geoderma, 2019Co-Authors: Hans W. Klopp, Francisco J. Arriaga, William J. Likos, William F. BleamAbstract:Abstract Soil sodification and salinization present a global soil degradation risk to agricultural production since they affect soil hydraulic properties. Soils containing smectite clays have been found to be most sensitive to Sodicity although little research exists directly relating Sodicity to clay swelling under varying levels of salinity and Exchangeable Sodium Percentage (ESP). The goal of this study is to determine whether soil swelling related measurements can be a proxy to determine soil sensitivity to exchangeable sodium. This study examined the response of three smectitic soils treated with salt solutions having concentrations ranging between 5 and 40 mmolc dm−3 and ESP levels between 0 and 50% to create differing degrees of Sodicity. Whole soil Atterberg limits and the coefficient of linear extensibility (COLE) were measured prior to and after treatments. Liquid limit, plasticity index and the coefficient of linear extensibility increased for all three soils after treatment with a salt concentration of 5 mmolc dm−3 at an ESP of 25 and 50% and 10 mmolc dm−3 at an ESP of 50%. Comparing liquid limit of low salinity treatment at 50% ESP to low salinity 0% ESP revealed the presence of swelling smectite clay and the sensitivity of the soils to Sodicity and a soil measurement to identify soil Sodicity risk.
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Atterberg limits and shrink/swell capacity of soil as indicators for sodium sensitivity within a gradient of soil exchangeable sodium percentage and salinity
Geoderma, 2019Co-Authors: Hans W. Klopp, Francisco J. Arriaga, William J. Likos, William F. BleamAbstract:Abstract Soil sodification and salinization present a global soil degradation risk to agricultural production since they affect soil hydraulic properties. Soils containing smectite clays have been found to be most sensitive to Sodicity although little research exists directly relating Sodicity to clay swelling under varying levels of salinity and Exchangeable Sodium Percentage (ESP). The goal of this study is to determine whether soil swelling related measurements can be a proxy to determine soil sensitivity to exchangeable sodium. This study examined the response of three smectitic soils treated with salt solutions having concentrations ranging between 5 and 40 mmolc dm−3 and ESP levels between 0 and 50% to create differing degrees of Sodicity. Whole soil Atterberg limits and the coefficient of linear extensibility (COLE) were measured prior to and after treatments. Liquid limit, plasticity index and the coefficient of linear extensibility increased for all three soils after treatment with a salt concentration of 5 mmolc dm−3 at an ESP of 25 and 50% and 10 mmolc dm−3 at an ESP of 50%. Comparing liquid limit of low salinity treatment at 50% ESP to low salinity 0% ESP revealed the presence of swelling smectite clay and the sensitivity of the soils to Sodicity and a soil measurement to identify soil Sodicity risk.
Hao Yu - One of the best experts on this subject based on the ideXlab platform.
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mapping soil salinity Sodicity by using landsat oli imagery and plsr algorithm over semiarid west jilin province china
Sensors, 2018Co-Authors: Hao Yu, Baojia Du, Zongming Wang, Liangjun Hu, Bai ZhangAbstract:Soil salinity and Sodicity can significantly reduce the value and the productivity of affected lands, posing degradation, and threats to sustainable development of natural resources on earth. This research attempted to map soil salinity/Sodicity via disentangling the relationships between Landsat 8 Operational Land Imager (OLI) imagery and in-situ measurements (EC, pH) over the west Jilin of China. We established the retrieval models for soil salinity and Sodicity using Partial Least Square Regression (PLSR). Spatial distribution of the soils that were subjected to hybridized salinity and Sodicity (HSS) was obtained by overlay analysis using maps of soil salinity and Sodicity in geographical information system (GIS) environment. We analyzed the severity and occurring sizes of soil salinity, Sodicity, and HSS with regard to specified soil types and land cover. Results indicated that the models’ accuracy was improved by combining the reflectance bands and spectral indices that were mathematically transformed. Therefore, our results stipulated that the OLI imagery and PLSR method applied to mapping soil salinity and Sodicity in the region. The mapping results revealed that the areas of soil salinity, Sodicity, and HSS were 1.61 × 106 hm2, 1.46 × 106 hm2, and 1.36 × 106 hm2, respectively. Also, the occurring area of moderate and intensive Sodicity was larger than that of salinity. This research may underpin efficiently mapping regional salinity/Sodicity occurrences, understanding the linkages between spectral reflectance and ground measurements of soil salinity and Sodicity, and provide tools for soil salinity monitoring and the sustainable utilization of land resources.
Tim Sutton - One of the best experts on this subject based on the ideXlab platform.
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bread wheat with high salinity and Sodicity tolerance
Frontiers in Plant Science, 2019Co-Authors: Yusuf Genc, Juian Taylor, Graham Lyons, Judy Cheong, Marie Appelbee, Klaus Oldach, Tim SuttonAbstract:Soil salinity and Sodicity are major constraints to global cereal production, but breeding for tolerance has been slow. Narrow gene pools, over-emphasis on the sodium (Na+) exclusion mechanism, little attention to osmotic stress/tissue tolerance mechanism(s) in which accumulation of inorganic ions such as Na+ is implicated, and lack of a suitable screening method have impaired progress. The aims of this study were to discover novel genes for Na+ accumulation using genome-wide association studies, compare growth responses to salinity and Sodicity in low-Na+ bread Westonia with Nax1 and Nax2 genes and high-Na+ bread wheat Baart-46, and evaluate growth responses to salinity and Sodicity in bread wheats with varying leaf Na+ concentrations. The novel high-Na+ bread wheat germplasm, MW#293, had higher grain yield under salinity and Sodicity, in absolute and relative terms, than the other bread wheat entries tested. Genes associated with high Na+ accumulation in bread wheat were identified, which may be involved in tissue tolerance/osmotic adjustment. As most modern bread wheats are efficient at excluding Na+, further reduction in plant Na+ is unlikely to provide agronomic benefit. The salinity and Sodicity tolerant germplasm MW#293 provides an opportunity for the development of future salinity/Sodicity tolerant bread wheat.
Alex Onus - One of the best experts on this subject based on the ideXlab platform.
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Spatial Analysis of Soil Salinity and Soil Structural Stability in a Semiarid Region of New South Wales, Australia
Environmental Management, 2008Co-Authors: Inakwu O. A. Odeh, Alex OnusAbstract:Salt-affected soils are a major threat to agriculture especially in the semiarid regions of the world. The effective management of these soils requires adequate understanding of not only how water and, hence, solutes are transported within the soil, but also how soil salinity and Sodicity spatially interact to determine soil structural breakdown. For sustainable agricultural production, information on quantitative soil quality, such as salinity, is required for effective land management and environmental planning. In this study, quantitative methods for mapping indicators of soil structural stability, namely salinity and Sodicity, were developed to assess the effect of these primary indicators on soil structural breakdown. The current levels of soil salinity, as measured by electrical conductivity (EC) of the soil/water suspension, soil Sodicity, represented by exchangeable sodium percentage (ESP), and aggregate stability, were assessed. Remote sensing, geographical information system (GIS), and geostatistical techniques—primarily regression-kriging and indicator-kriging—were used to spatially predict the soil Sodicity and salinity. The patterns of salinity (EC) and Sodicity (ESP > 5%) were identified. The effect of land use on these soil quality indicators was found to be minimal. Co-spatial patterns were elucidated between sodic soils (defined by ESP > 5%) and highly probable mechanically dispersive soils predicted from indicator-kriging of ASWAT scores. It was established that the incorporation of EC with ESP into an objective index, called electrolyte stability index (ESI = ESP/EC), gave a good indication of soil dispersion, although the threshold ESI value below which effective structural breakdown might occur is 0.025, which is twice as small as the expected 0.05. The discrepancies between ESI and ASWAT scores suggest that other soil factors than salinity and Sodicity are affecting soil structural breakdown. This calls for further investigation. The study provides valuable information in the form of risk zones of soil structural breakdown for land management. These zones, with a probability of mechanical soil dispersion of >0.70, require immediate management attention with greater monitoring and amelioration techniques, particularly gypsum or lime application and/or altered cultivation techniques.
