Water status of isolated Negev desert populations of Acacia raddiana with different mortality levels Academic Article uri icon

abstract

  • Many populations of native Acacia raddiana trees in ephemeral riverbeds in the Negev desert are suffering from high mortality. Road-building techniques that cut off water to trees in downstream populations and the pumping of aquifers for agriculture have been mooted as causes of this mortality. We studied the water relations of nine isolated populations of these trees using a pressure chamber and stable carbon isotopes in order to determine whether current water stress could be the cause of this mortality. High mortality populations had more negative water potentials, lower relative water contents, and lower cell water volumes at full turgor than low mortality populations. Thus, mortality is correlated with current inter-population differences in water stress. However, there was no difference in water potentials between trees upstream and downstream of roads. Furthermore, greater water …

publication date

  • September 1, 2003