title: Regionalizing potential for microbial bypass flow through New Zealand soils.
abstract: Microbial breakthrough curves of 12 soils, generated by the application of dairy shed effluent followed by continuous artificial rainfall for one pore volume at 5 mm h(-1) onto large undisturbed soil cores, have been ranked as high, medium, or low potential for microbial bypass flow. The ranking is based on the position of the peak in the breakthrough curve. Knowledge of soil properties that affect microbial transport through soil gained from the microbial breakthrough curves was linked to soil classes, or to their accessory properties, of the New Zealand Soil Classification. Spatial depiction of the ratings has been achieved via the national 1:50,000 scale soil map. Soils with a drainage impediment or those with well developed soil structure have a high potential for microbial bypass flow, whereas soils from tephra and Recent Soils with less developed, porous, soil structure have a low potential for microbial bypass flow. The risk rankings should be considered as maxima because management may change some rankings.
authors.affiliation: Landcare Research, Private Bag 3127, Hamilton, New Zealand. mcleodm@landcareresearch.co.nz
authors.forename: Malcolm
authors.initials: M
authors.lastname: McLeod
authors.forename: Jackie
authors.initials: J
authors.lastname: Aislabie
authors.forename: Janine
authors.initials: J
authors.lastname: Ryburn
authors.forename: Alexandra
authors.initials: A
authors.lastname: McGill
mesh_terms: D009520:New Zealand; D012987:Soil; D012988:Soil Microbiology; D014865:Waste Disposal, Fluid
chemical_list: D012987:Soil