Microbial transport from dairying under two spray-irrigation systems in Canterbury, New Zealand.

摘要: Transport through the soil and vadose zone to groundwater of Escherichia coli, fecal coliforms, Campylobacter spp. from pasturing dairy cows was studied on two working farms under a traveling irrigator center pivot system. Leachate collected 1.5 m depth using large linear lysimeter over period 4 yr after rainfall or irrigation applied irrigator. There little transport coliforms Campylabacter applications 55 mm. some at 80 mm (corresponding plus heavy rainfall) but no detectable Campylobacter. When fresh cow pats were placed half plots with an 80-mm water application, there Campylobacter, levels low (≤4 MPN L ―1 ). Groundwater farm spray monitored monthly September 2001 June 2007, 60% samples being downgradient wells. coli detected in 5.4 2.8% upgradient wells, respectively, concentrations □1 cfu 100 mL . 0.7% study period, equal percentages up- The results indicate minimal impact dairying these sites microbial quality as result irrigators rates approximately every 2 wk 18 3 d.