02511naa a2200277 a 450000100080000000500110000800800410001910000160006024501260007626000090020252017480021165000120195965000110197165000090198265000130199165000090200465300230201365300170203665300210205365300200207470000170209470000190211170000160213070000180214677300690216417895652017-04-04       1995    bl ---       0--  u    #d1 aROSS, D. J.  aSoil microbial biomass, C and N mineralization, and enzyme activities in a hill pasturebinfluence of grazing management.  c1995  aGrazing and fertilizer management practices are of prime importance for maintaning summer moist hill pasture of introduced grasses and clovers in New Zealand for sheep and cattle production. The influence of withholding grazing ( a pastoral fallow) from spring to late summer on microbial biomass. C and N mineralization, and enzyme activities was investigated in a Typic Dystrochrept soil from unfertilized (rock phosphate and elemental S) low-fertility pastures at a temperate hill site. The fallow increased pasture but not legume growth in the following year in the unfertilized treatment, but had no effect on pasture or legume growth in fetilized plots. High background levels of thje biochemical properties and very variable rates of N mineralization, complicated data interpretation. Extractable-C concentration and CO2-C production were enhanced at the completion of the fallow. Increases in net N mineralization (14-56 days incubation), following initial immobilization, after the fallow were clearly indicated in the underfertilized treatment, but were less distinct in the fertilized treatment. The fallow had no detectable influence on the concentratioins of total C and N or microbial C and P or on inverse, phosphodiesterase and sulfatase activities. Some small changes in microbial N and an increased proportion of bacteria in the microbial population were, however, suggested. Results are consistent with the concept of fallowing giving a short-term increase in pools of readily decomposable soil organic matter. Generally, the changes that did occur in these soil biochemical properties are, with the partial exception of increased N availability, unlikely to have had any pronounced impact on subsequent pasture performance.  abiomass  afallow  asoil  aBiomassa  aSolo  aCiclo de nutriente  aHill pasture  aNutrient cycling  aPasto de colina1 aSPEIR, T. W.1 aKETTLES, H. A.1 aTATE, K. R.1 aMACKAY, A. D.  tAustralian Journal of Soil Researchgv.33, n.6, p.943-959, 1995.