Characterization of pathogen transport in overland flow

cryptosporidium;rotavirus;agricultural runoff;vegetative filter strip;soil

Davidson, Paul C.

关键词: cryptosporidium;    rotavirus;    agricultural runoff;    vegetative filter strip;    soil;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/15507/1_Davidson_Paul.pdf?sequence=2&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Overland transport kinetics of pathogens are controlled, in large part, by soil and vegetation.With an increasing number of concentrated animal operations, there is becoming a greater need to dispose of a vast amount of manure in a single, localized area.Animal manure contains a substantial amount of microbial pathogens, including Cryptosporidium parvum and rotavirus that may pose a threat of potential contamination of water resources.This study examines the kinetics of C. parvum and rotavirus in overland transport, with an overall objective of optimizing the design of best management practices, especially vegetative filter strips.Three soil types are tested (Catlin silt-loam, Alvin fine sandy-loam, Darwin silty-clay), spanning the entire spectrum of typical Illinois soils, in terms of soil texture.A 20-minute rainfall event is produced using a small-scale (1.07 m x 0.66 m) laboratory rainfall simulator over a soil box measuring 0.67 m x 0.33 m.Each soil type is tested for pathogen transport kinetics with bare and vegetated surface conditions.Surface runoff, soil cores, and near-surface runoff are each analyzed for infective C. parvum oocysts and infective rotavirus particles using cell-culture infectivity assays.Results show that vegetation reduces the recovery of infective oocysts in surface runoff by an average of 62% and rotavirus particles by an average of 73%, in addition to delaying the time to the peak recovery.Recovery of infective rotavirus particles from surface runoff of bare Alvin (high sand content) soil is seven times higher than that of infective oocysts.Recovery from surface runoff of bare Darwin (high clay content) soil is nearly one and a half times more for C. parvum than for rotavirus, with the recovery of C. parvum oocysts approaching 40%.Recovery from the soil cores was slightly higher for C. parvum (0.06%) than for rotavirus (0.05%) in the case of the bare Alvin soil, but was slightly higher for rotavirus (0.92%) than C. parvum (0.19%) for the bare Darwin soil condition.