Influence of soil on fecal indicator organisms in a tidally influenced subtropical environment
Influence of soil on fecal indicator organisms in a tidally influenced subtropical environment
复制标题
DOI：
10.1128/aem.68.3.1165-1172.2002
复制
发表时间：
2002-03-01
影响因子：
4.4
通讯作者：
Palmer, CJ
中科院分区：
文献类型：
--
作者：
Desmarais, TR;Solo-Gabriele, HM;Palmer, CJ
在娱乐水体中释放到沿海环境中的粪便指示细菌的潜在再生长一直受到关注，特别是在热带和亚热带地区，这些细菌的数量可以人为地升高，超出粪便的影响。通过一系列现场采样和实验室实验，使用大肠杆菌，肠球菌，产气荚膜梭菌在河水，沉积物和土壤中的原位密度，确定指标细菌再生长的影响因素的任务得到解决。实地取样工作包括收集沿河岸横截面沿着的表层沉积物、20厘米深的土芯以及偏远地区的其他表层土壤。除了现场取样外，还进行了两种类型的实验室实验。第一个实验研究了在河水中加入无菌和未无菌沉积物后细菌的存活情况。第二个实验是为了模拟由于潮汐周期的湿润和干燥的影响。抽样研究的结果发现E. coli和C.产气荚膜杆菌在靠近水边的河岸表层沉积物中。从土芯中获得的地下样品中发现了大量的产气荚膜梭菌。实验室实验的结果显示肠球菌和大肠杆菌的再生量很大。大肠杆菌，模拟潮汐和添加无菌沉淀物。未观察到产气荚膜梭菌的再生长。这项研究表明，有必要进一步评估热带和亚热带水系内的指示微生物的特性，天然植被，土壤覆盖，和长期沉积物积累。在这些地区，使用传统的指示微生物来管理水体的娱乐用途可能不合适。
The potential regrowth of fecal indicator bacteria released into coastal environments in recreational water bodies has been of concern, especially in tropical and subtropical areas where the number of these bacteria can be artificially elevated beyond that from fecal impacts alone. The task of determining the factors that influence indicator bacterial regrowth was addressed though a series of field sampling and laboratory experiments using in situ densities of Escherichia coli, enterococci, and Clostridium perfringens in river water, sediment, and soil. Field sampling efforts included the collection of surface sediments along the cross section of a riverbank, a 20-cm-deep soil core, and additional surface soils from remote locations. In addition to field sampling, two types of laboratory experiments were conducted. The first experiment investigated the survival of bacteria already present in river water with the addition of sterile and unsterile sediment. The second experiment was designed to simulate the wetting and drying effects due to tidal cycles. The results from the sampling study found elevated numbers of E. coli and C. perfringens in surficial sediments along the riverbank near the edge of the water. C perfringens was found in high numbers in the subsurface samples obtained from the soil core. Results from laboratory experiments revealed a significant amount of regrowth for enterococci and E. coli with the simulation of tides and addition of sterile sediment. Regrowth was not observed for C perfringens. This study demonstrates the need to further evaluate the characteristics of indicator microbes within tropical and subtropical water systems where natural vegetation, soil embankments, and long-term sediment accumulation are present. In such areas, the use of traditional indicator microbes to regulate recreational uses of a water body may not be appropriate.