1. a Dortoral candidate, Department of Geography , Hebrew University of Jerusalem , Mt Scopus, Jerusalem, 91905, Israel Phone: Fax: E-mail:
2. b Department of Geography , Hebrew University of Jerusalem , Mt Scopus, Jerusalem, 91905, Israel Phone: Fax: E-mail:
3. c Department of Geography , Hebrew University of Jerusalem , Mt Scopus, Jerusalem, 91905, Israel Phone: Fax: E-mail: