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• 281. [Image] Geoscientific Studies and the Potential of the Natural Environment

  	Citation × Citation Citation Abstract Copy Title: Geoscientific Studies and the Potential of the Natural Environment Year: 1975 Title: Geoscientific Studies and the Potential of the Natural Environment Year: 1975 Close

• 282. [Image] Gulf Faces a Growing Food Crisis

  	Citation × Citation Citation Abstract Copy Title: Gulf Faces a Growing Food Crisis Year: 1981 Title: Gulf Faces a Growing Food Crisis Year: 1981 Close

• 283. [Image] Negev--Israel's Desert Wonderland

  	Citation × Citation Citation Abstract Copy Title: Negev--Israel's Desert Wonderland Year: 1991 Title: Negev--Israel's Desert Wonderland Year: 1991 Close

• 284. [Image] Study of water consumption of cotton in the Euphrates Valley

  	Citation × Citation Citation Abstract Copy Title: Study of water consumption of cotton in the Euphrates Valley Year: 1972 Title: Study of water consumption of cotton in the Euphrates Valley Year: 1972 Close

• 285. [Image] Volume 2 : Water Resources

  	Citation × Citation Citation Abstract Copy Title: Volume 2 : Water Resources Author: Howard Humphreys & Sons Year: 1978 Title: Volume 2 : Water Resources Author: Howard Humphreys & Sons Year: 1978 Close

• 286. [Image] Studies on Dry land Farming at the College of Agriculture and Forestry , University of Mogul

  	Citation × Citation Citation Abstract Copy Title: Studies on Dry land Farming at the College of Agriculture and Forestry , University of Mogul Year: 1979 Title: Studies on Dry land Farming at the College of Agriculture and Forestry , University of Mogul Year: 1979 Close

• 287. [Image] Is the Nile Drying Up?

  	Citation × Citation Citation Abstract Copy Title: Is the Nile Drying Up? Author: Derrick, Jonathan Year: 1987 Title: Is the Nile Drying Up? Author: Derrick, Jonathan Year: 1987 Close

• 288. [Image] Ground Water in the eastern Mediterranean and Western Asia

  	Citation × Citation Citation Abstract Copy Title: Ground Water in the eastern Mediterranean and Western Asia Year: 1982 Title: Ground Water in the eastern Mediterranean and Western Asia Year: 1982 Close

• 289. [Article] Physiological impacts of groundwater and surface water application on desert graminoids of different geographic origin

  Desert plant communities are among the most sensitive to changes in soil water conditions. In areas with shallow aquifers, it is important to understand both the effects of groundwater alterations on ...

  Citation × Citation Citation Abstract Copy Title: Physiological impacts of groundwater and surface water application on desert graminoids of different geographic origin Author: Abdallah, Mohamed (Mohamed Ahmed B.) Desert plant communities are among the most sensitive to changes in soil water conditions. In areas with shallow aquifers, it is important to understand both the effects of groundwater alterations on vegetation and how changes in surface-soil water affect plant water uptake. Studies in arid environments have evaluated the effect of groundwater variation and simulated precipitation on plant production and vegetation condition but it is not clear if plants respond equally to the availability of surface water or groundwater. This study was conducted in a greenhouse to evaluate growth and physiology of three desert graminoids (Distichlis spicata, Leymus triticoides, and Juncus arcticus) as affected by surface water availability (mimicking precipitation) or subsurface water availability (mimicking groundwater). The species of study are amply distributed in wetlands and open rangelands of western USA and were collected from two sources of ecological distribution: an area near Bishop, California, and an area near Burns, Oregon. The Bishop, California area has a characteristic shallow aquifer and plants in this area are considered somewhat dependent on groundwater. The Burns, Oregon, area sustains the same species but in a variety of soil moisture conditions. We had two general hypotheses for this study: 1) that the use of surface water is favored over groundwater and 2) that there are ecotypic differences in the response of the species to water availability. The first hypothesis was partially supported by the results of the study, but variability existed among species. However, when all species had equal access to both surface soil water and groundwater plants tended to preferentially use surface water. The second hypothesis was clearly supported by our results. Although the mechanism is not clear, it is possible that an area with periodic and predictable shallow groundwater underlying a dry or saline soil layer, such as the California site, might favor plant ecotypes with high proficiency in water acquisition by deeper roots. Knowledge of water use characteristics of vegetation is essential to provide management guidelines for areas where plants depend on both surface-soil water and groundwater. This study contributed to that knowledge. Further studies on ecotypic variation and an expansion to different species that inhabit areas with shallow aquifers are recommended. Title: Physiological impacts of groundwater and surface water application on desert graminoids of different geographic origin Author: Abdallah, Mohamed (Mohamed Ahmed B.) Desert plant communities are among the most sensitive to changes in soil water conditions. In areas with shallow aquifers, it is important to understand both the effects of groundwater alterations on vegetation and how changes in surface-soil water affect plant water uptake. Studies in arid environments have evaluated the effect of groundwater variation and simulated precipitation on plant production and vegetation condition but it is not clear if plants respond equally to the availability of surface water or groundwater. This study was conducted in a greenhouse to evaluate growth and physiology of three desert graminoids (Distichlis spicata, Leymus triticoides, and Juncus arcticus) as affected by surface water availability (mimicking precipitation) or subsurface water availability (mimicking groundwater). The species of study are amply distributed in wetlands and open rangelands of western USA and were collected from two sources of ecological distribution: an area near Bishop, California, and an area near Burns, Oregon. The Bishop, California area has a characteristic shallow aquifer and plants in this area are considered somewhat dependent on groundwater. The Burns, Oregon, area sustains the same species but in a variety of soil moisture conditions. We had two general hypotheses for this study: 1) that the use of surface water is favored over groundwater and 2) that there are ecotypic differences in the response of the species to water availability. The first hypothesis was partially supported by the results of the study, but variability existed among species. However, when all species had equal access to both surface soil water and groundwater plants tended to preferentially use surface water. The second hypothesis was clearly supported by our results. Although the mechanism is not clear, it is possible that an area with periodic and predictable shallow groundwater underlying a dry or saline soil layer, such as the California site, might favor plant ecotypes with high proficiency in water acquisition by deeper roots. Knowledge of water use characteristics of vegetation is essential to provide management guidelines for areas where plants depend on both surface-soil water and groundwater. This study contributed to that knowledge. Further studies on ecotypic variation and an expansion to different species that inhabit areas with shallow aquifers are recommended. Close

• 290. [Article] ENSO Controls Interannual Fire Activity in Southeast Australia

  El Niño–Southern Oscillation (ENSO) is the main mode controlling the variability in the ocean-atmosphere system in the South Pacific. While the ENSO influence on rainfall regimes in the South Pacific is ...

  Citation × Citation Citation Abstract Copy Title: ENSO Controls Interannual Fire Activity in Southeast Australia Author: Mariani, Michela, Fletcher, Michael-Shawn, Holz, Andrés, Nyman, Petter Year: 2016 El Niño–Southern Oscillation (ENSO) is the main mode controlling the variability in the ocean-atmosphere system in the South Pacific. While the ENSO influence on rainfall regimes in the South Pacific is well documented, its role in driving spatiotemporal trends in fire activity in this region has not been rigorously investigated. This is particularly the case for the highly flammable and densely populated southeast Australian sector, where ENSO is a major control over climatic variability. Here we conduct the first region-wide analysis of how ENSO controls fire activity in southeast Australia. We identify a significant relationship between ENSO and both fire frequency and area burnt. Critically, wavelet analyses reveal that despite substantial temporal variability in the ENSO system, ENSO exerts a persistent and significant influence on southeast Australian fire activity. Our analysis has direct application for developing robust predictive capacity for the increasingly important efforts at fire management. Title: ENSO Controls Interannual Fire Activity in Southeast Australia Author: Mariani, Michela, Fletcher, Michael-Shawn, Holz, Andrés, Nyman, Petter Year: 2016 El Niño–Southern Oscillation (ENSO) is the main mode controlling the variability in the ocean-atmosphere system in the South Pacific. While the ENSO influence on rainfall regimes in the South Pacific is well documented, its role in driving spatiotemporal trends in fire activity in this region has not been rigorously investigated. This is particularly the case for the highly flammable and densely populated southeast Australian sector, where ENSO is a major control over climatic variability. Here we conduct the first region-wide analysis of how ENSO controls fire activity in southeast Australia. We identify a significant relationship between ENSO and both fire frequency and area burnt. Critically, wavelet analyses reveal that despite substantial temporal variability in the ENSO system, ENSO exerts a persistent and significant influence on southeast Australian fire activity. Our analysis has direct application for developing robust predictive capacity for the increasingly important efforts at fire management. Close