Transport of Cryptosporidium parvum oocysts through vegetated buffer strips and estimated filtration efficiency.
نویسندگان
چکیده
Vegetated buffer strips were evaluated for their ability to remove waterborne Cryptosporidium parvum from surface and shallow subsurface flow during simulated rainfall rates of 15 or 40 mm/h for 4 h. Log(10) reductions for spiked C. parvum oocysts ranged from 1.0 to 3.1 per m of vegetated buffer, with buffers set at 5 to 20% slope, 85 to 99% fescue cover, soil textures of either silty clay (19:47:34 sand-silt-clay), loam (45:37:18), or sandy loam (70:25:5), and bulk densities of between 0.6 to 1.7 g/cm(3). Vegetated buffers constructed with sandy loam or higher soil bulk densities were less effective at removing waterborne C. parvum (1- to 2-log(10) reduction/m) compared to buffers constructed with silty clay or loam or at lower bulk densities (2- to 3-log(10) reduction/m). The effect of slope on filtration efficiency was conditional on soil texture and soil bulk density. Based on these results, a vegetated buffer strip comprised of similar soils at a slope of or=3 m should function to remove >or=99.9% of C. parvum oocysts from agricultural runoff generated during events involving mild to moderate precipitation.
منابع مشابه
Efficacy of vegetated buffer strips for retaining Cryptosporidium parvum.
Overland and shallow subsurface hydrologic transport of pathogenic Cryptosporidium parvum oocysts from cattle feces into surface drinking water supplies is a major concern on annual grasslands in California's central and southern Sierra Nevada foothills. Soil boxes (0.5 m wide x 1.1 m long x 0.3 m deep) were used to evaluate the ability of grass vegetated buffer strips to retain 2 x 10(8) spike...
متن کاملModeling Transport of Cryptosporidium Parvum Oocysts in Overland Flow
Cryptosporidium, a manure-borne protozoan parasite that is common in the environment, has recently been recognized as an important microbial contaminant of water. Cryptosporidium parvum (C. parvum) can cause infection and diarrhea in many mammalian hosts, including humans. Because cattle, particularly calves, are considered a major source of C. parvum , it is important to understand the movemen...
متن کاملOverland and near-surface transport of Cryptosporidium parvum from vegetated and nonvegetated surfaces.
Understanding microbial pathogen transport patterns in overland flow is important for developing best management practices for limiting microbial transport to water resources. Knowledge about the effectiveness of vegetative filter strips (VFS) to reduce pathogen transport from livestock confinement areas is limited. In this study, overland and near-surface transport of Cryptosporidium parvum ha...
متن کاملDeveloping risk models of Cryptosporidium transport in soils from vegetated, tilted soilbox experiments.
Transport of Cryptosporidium parvum through macroporous soils is poorly understood yet critical for assessing the risk of groundwater contamination. We developed a conceptual model of the physics of flow and transport in packed, tilted, and vegetated soilboxes during and immediately after a simulated rainfall event and applied it to 54 experiments implemented with different soils, slopes, and r...
متن کاملTransport of Cryptosporidium parvum oocysts in a silicon micromodel.
Effective removal of Cryptosporidium parvum oocysts by granular filtration requires the knowledge of oocyst transport and deposition mechanisms, which can be obtained based on real time microscopic observation of oocyst transport in porous media. Attachment of oocysts to silica surface in a radial stagnation point flow cell and in a micromodel, which has 2-dimensional (2-D) microscopic pore str...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Applied and environmental microbiology
دوره 68 11 شماره
صفحات -
تاریخ انتشار 2002