The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Morgan W Kelly - One of the best experts on this subject based on the ideXlab platform.
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phenotypic and transcriptomic responses to Salinity stress across genetically and geographically divergent tigriopus californicus populations
Molecular Ecology, 2018Co-Authors: Melissa B Debiasse, Yasmeen Kawji, Morgan W KellyAbstract:Species inhabiting the North American west coast intertidal must tolerate an extremely variable environment, with large fluctuations in both temperature and Salinity. Uncovering the mechanisms for this tolerance is key to understanding species' persistence. We tested for differences in Salinity tolerance between populations of Tigriopus californicus copepods from locations in northern (Bodega Reserve) and southern (San Diego) California known to differ in temperature, precipitation and humidity. We also tested for differences between populations in their transcriptomic responses to Salinity. Although these two populations have ~20% mtDNA sequence divergence and differ strongly in other phenotypic traits, we observed similarities in their phenotypic and transcriptomic responses to low and high Salinity stress. Salinity significantly affected respiration rate (increased under low Salinity and reduced under high Salinity), but we found no significant effect of population on respiration or a population by Salinity interaction. Under high Salinity, there was no population difference in knock-down response, but northern copepods had a smaller knock-down under low Salinity stress, corroborating previous results for T. californicus. Northern and southern populations had a similar transcriptomic response to Salinity based on a principle components analysis, although differential gene expression under high Salinity stress was three times lower in the northern population compared to the southern population. Transcripts differentially regulated under Salinity stress were enriched for "amino acid transport" and "ion transport" annotation categories, supporting previous work demonstrating that the accumulation of free amino acids is important for osmotic regulation in T. californicus.
Melissa B Debiasse - One of the best experts on this subject based on the ideXlab platform.
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phenotypic and transcriptomic responses to Salinity stress across genetically and geographically divergent tigriopus californicus populations
Molecular Ecology, 2018Co-Authors: Melissa B Debiasse, Yasmeen Kawji, Morgan W KellyAbstract:Species inhabiting the North American west coast intertidal must tolerate an extremely variable environment, with large fluctuations in both temperature and Salinity. Uncovering the mechanisms for this tolerance is key to understanding species' persistence. We tested for differences in Salinity tolerance between populations of Tigriopus californicus copepods from locations in northern (Bodega Reserve) and southern (San Diego) California known to differ in temperature, precipitation and humidity. We also tested for differences between populations in their transcriptomic responses to Salinity. Although these two populations have ~20% mtDNA sequence divergence and differ strongly in other phenotypic traits, we observed similarities in their phenotypic and transcriptomic responses to low and high Salinity stress. Salinity significantly affected respiration rate (increased under low Salinity and reduced under high Salinity), but we found no significant effect of population on respiration or a population by Salinity interaction. Under high Salinity, there was no population difference in knock-down response, but northern copepods had a smaller knock-down under low Salinity stress, corroborating previous results for T. californicus. Northern and southern populations had a similar transcriptomic response to Salinity based on a principle components analysis, although differential gene expression under high Salinity stress was three times lower in the northern population compared to the southern population. Transcripts differentially regulated under Salinity stress were enriched for "amino acid transport" and "ion transport" annotation categories, supporting previous work demonstrating that the accumulation of free amino acids is important for osmotic regulation in T. californicus.
Yasmeen Kawji - One of the best experts on this subject based on the ideXlab platform.
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phenotypic and transcriptomic responses to Salinity stress across genetically and geographically divergent tigriopus californicus populations
Molecular Ecology, 2018Co-Authors: Melissa B Debiasse, Yasmeen Kawji, Morgan W KellyAbstract:Species inhabiting the North American west coast intertidal must tolerate an extremely variable environment, with large fluctuations in both temperature and Salinity. Uncovering the mechanisms for this tolerance is key to understanding species' persistence. We tested for differences in Salinity tolerance between populations of Tigriopus californicus copepods from locations in northern (Bodega Reserve) and southern (San Diego) California known to differ in temperature, precipitation and humidity. We also tested for differences between populations in their transcriptomic responses to Salinity. Although these two populations have ~20% mtDNA sequence divergence and differ strongly in other phenotypic traits, we observed similarities in their phenotypic and transcriptomic responses to low and high Salinity stress. Salinity significantly affected respiration rate (increased under low Salinity and reduced under high Salinity), but we found no significant effect of population on respiration or a population by Salinity interaction. Under high Salinity, there was no population difference in knock-down response, but northern copepods had a smaller knock-down under low Salinity stress, corroborating previous results for T. californicus. Northern and southern populations had a similar transcriptomic response to Salinity based on a principle components analysis, although differential gene expression under high Salinity stress was three times lower in the northern population compared to the southern population. Transcripts differentially regulated under Salinity stress were enriched for "amino acid transport" and "ion transport" annotation categories, supporting previous work demonstrating that the accumulation of free amino acids is important for osmotic regulation in T. californicus.
Amal Allbed - One of the best experts on this subject based on the ideXlab platform.
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assessing soil Salinity using soil Salinity and vegetation indices derived from ikonos high spatial resolution imageries applications in a date palm dominated region
Geoderma, 2014Co-Authors: Amal Allbed, Lali Kuma, Yousef Y AldakheelAbstract:Abstract In saline soils, the spectral reflectance of either salt features at the surface or of vegetation that was negatively affected by salt varies with different Salinity levels. Thus, several indices for vegetation and soil Salinity have been developed. This study was conducted to assess the soil Salinity levels in the Al-Hassa Oasis, which is dominated by date palm vegetation, in the eastern province of Saudi Arabia. Ground and remote sensing data were used to determine if any existing vegetation and soil Salinity indices could be used to assess the soil Salinity of communities vegetated with date palm. A systematic regular grid-sampling approach was used to collect a total of 149 composite soil samples from the study area. Thirteen broadband indices, which encompassed vegetation and soil Salinity indices, were extracted from IKONOS satellite images. The predictive power of these indices for soil Salinity was examined. The study area was dominated by areas of high Salinity. Among the investigated indices, the Soil-Adjusted Vegetation Index (SAVI), Normalized Differential Salinity Index (NDSI) and Salinity Index (SI-T) yielded the best results for assessing the soil Salinity of cultivated lands with dense and uniform vegetation. In contrast, the NDSI and SI-T exhibited the highest significant correlation with Salinity for less densely vegetated lands and bare soils. Generally, the soil Salinity in the areas that were dominated by date palms was successfully assessed by broadband vegetation and soil Salinity indices that were extracted from the IKONOS satellite images.
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soil Salinity mapping and monitoring in arid and semi arid regions using remote sensing technology a review
ARS, 2013Co-Authors: Amal Allbed, Lalit KumarAbstract:Soil Salinity is a serious environmental problem especially in arid and semiarid areas. It either occurs naturally or is human-induced. High levels of soil Salinity negatively affect crop growth and productivity leading land degradation ultimately. Thus, it is important to monitor and map soil Salinity at an early stage to enact effective soil reclamation program that helps lessen or prevent future increase in soil Salinity. Remote sensing has outperformed the traditional method for assessing soil Salinity offering more informative and professional rapid assessment techniques for monitoring and mapping soil Salinity. Soil Salinity can be identified from remote sensing data obtained by different sensors by way of direct indicators that refer to salt features that are visible at the soil surface as well as indirect indicators such as the presence of halophytic plant and assessing the performance level of salt-tolerant crops. The purposes of this paper are to 1) discuss some soil Salinity indicators; 2) review the satellite sensors and methods used for remote monitoring, detecting and mapping of soil Salinity, particularly in arid and semi-arid regions; 3) review various spectral vegetation and Salinity indices that have been developed and proposed for soil Salinity detection and mapping, with an emphasis on soil Salinity mapping and assessment in arid and semi-arid regions; and 4) highlight the most important issues limiting the use of remote sensing for soil Salinity mapping, particularly in arid and semi-arid regions.
Yousef Y Aldakheel - One of the best experts on this subject based on the ideXlab platform.
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assessing soil Salinity using soil Salinity and vegetation indices derived from ikonos high spatial resolution imageries applications in a date palm dominated region
Geoderma, 2014Co-Authors: Amal Allbed, Lali Kuma, Yousef Y AldakheelAbstract:Abstract In saline soils, the spectral reflectance of either salt features at the surface or of vegetation that was negatively affected by salt varies with different Salinity levels. Thus, several indices for vegetation and soil Salinity have been developed. This study was conducted to assess the soil Salinity levels in the Al-Hassa Oasis, which is dominated by date palm vegetation, in the eastern province of Saudi Arabia. Ground and remote sensing data were used to determine if any existing vegetation and soil Salinity indices could be used to assess the soil Salinity of communities vegetated with date palm. A systematic regular grid-sampling approach was used to collect a total of 149 composite soil samples from the study area. Thirteen broadband indices, which encompassed vegetation and soil Salinity indices, were extracted from IKONOS satellite images. The predictive power of these indices for soil Salinity was examined. The study area was dominated by areas of high Salinity. Among the investigated indices, the Soil-Adjusted Vegetation Index (SAVI), Normalized Differential Salinity Index (NDSI) and Salinity Index (SI-T) yielded the best results for assessing the soil Salinity of cultivated lands with dense and uniform vegetation. In contrast, the NDSI and SI-T exhibited the highest significant correlation with Salinity for less densely vegetated lands and bare soils. Generally, the soil Salinity in the areas that were dominated by date palms was successfully assessed by broadband vegetation and soil Salinity indices that were extracted from the IKONOS satellite images.