Jan 3, 1995 - Bioindicators of soil health, based on soil biological properties, would be used along with other indicators based on the chemical and physical ...
Australian Journal of Experimental Agriculture, 1995,35, 1015-28
1015
Evaluation of soil biological properties as potential bioindicators of soil health C. E. pankhurstAB,B. G. ~ a w k eH. ~ J. ~ ~, c ~ o n a lC.d A. ~ KrkbyAB, ~ , J. C. ~ u c k e r f i e l d ~ ~ , I? ~ i c h e l s e nK. ~ ,A. ~ ' ~ r i e Vn V ~ S. , R. ~ u ~and t B.a M.~ DoubeAB A
CSIRO Division of Soils, Glen Osmond, SA 5064, Australia. Cooperative Research Centre for Soil and Land Management, Glen Osmond, SA 5064, Australia. Soil Science Department, University of Adelaide, Glen Osmond, SA 5064, Australia.
Summary. Two long-term field trials in South Australia were used to detect and characterise changes in soil biological properties that were a consequence of different agricultural management. The properties examined were total bacteria, fungi, and actinomycetes; total pseudomonads; cellulolytic bacteria a n d fungi; mycorrhizal fungi; plant root pathogens (Gaeumannomyces graminis var. tritici, Rhizoctonia solani, Pythium irregulare); bacterial-feeding protozoa; soil mesofauna (collembola and acari); earthworms; microbial biomass; C and N mineralisation; in situ C 0 2 respiration; cellulose decomposition; and soil enzyme activity (peptidase, phosphatase, sulfatase). T h e sensitivity of these biological properties was assessed to tillage (no-tillage v. conventional cultivation), stubble management (stubble retained v. stubble harvested), crop rotation (continuous wheat v. wheat-sown pasture), and
N fertilisation (nil v. 8 0 kg N/ha applied during the crop phase). Tillage, stubble management, crop rotation, and N fertilisation significantly (P0.05) of tillage plus stubble management, crop rotation, N fertiliser, or time of sampling on populations of pseudomonads, fungi, and actinomycetes. However, populations of fungi and actinomycetes tended (P = 0.10 for fungi and P = 0.13 for actinomycetes) to be higher in no-till soil where stubble was retained, than in cultivated soil where stubble was harvested. Total bacteria showed trends towards higher populations in cultivated soil ( P = 0.13) and soil under continuous wheat ( P = 0.12), and lower ( P = 0.10) populations where N had been applied. There were significant (P
