| Popis: |
Mass conversion of native vegetation to agricultural land-use triggered secondary salinity, a hydrological imbalance, which has damaged more than 1.75 million ha of farmland in south-western Australia. Various types of reforestation have been proposed and tested to restore the hydrological balance, however the economic returns from these cannot compete with existing farm practice and land-holders thus have a reluctance to adopt. An alternative approach has been to reforest abandoned saline areas with salinity and/or water-logging tolerant trees to avoid displacement of farming activities and to minimize opportunity costs. We propose an improved evaluation methodology for saline site reforestation and in this paper test its feasibility. Three eucalypts species (Eucalyptus salubris, E. camaldulensis and E. sargentii) were planted adjacent to a salt scald in Wickepin, Western Australia, and their survival and growth were monitored under increasing soil salinity ranging from moderate (ECe: 400-800 mS m-1), high (800-1,600 mS m-1) or extreme (>1,600 mS m-1) with shallow (< 1 m depth) saline ground water (EC: 2,000-3,000 mS m-1). Survival and growth of E. sargentii and E. salubris in the saline discharge areas were comparable to those in the arable area, and reforestation by these species can thus avoid land competition and opportunity costs. |
