Abundance and diversity of fungi in a saline soil in central-west New South Wales, Australia

Soil salinity is a major threat to agricultural productivity and natural ecosystems in Australia. The effect of rising salinity on soil organisms in general and fungi in particular is almost unknown in Australia. The purpose of the study reported in this paper is to examine the effects of salinity on fungal abundance and diversity in a saline soil in a dryland-agricultural region of central-west NSW. Soil fungal abundance and diversity were compared across four sampling sites in spring 2005 and autumn 2006. Species richness, diversity measurement using Shannon-Wiener index, and evenness measurement using Smith and Wilson index of soil fungi were obtained by sampling soil from 0-10 and 10-20 cm depths, and culturing fungi using Dilution plate and Warcup's plate methods. Soil salinity recorded at the time of sampling did not exceed 2 dS/m, but a negative correlation occurred between soil salinity and soil fungal abundance in spring 2005 and autumn 2006 (ANOVA; p < 0.05). No relationship between soil salinity and fungal diversity existed. Penicillium was the dominant species in 30-40% of the identified fungal samples. Also no correlation existed between low fungal abundance and diversity in salt-affected soils with little or no vegetation cover.