Byappanahalli M, Fujioka R
Water Resources Research Center, University of Hawaii, Honolulu, HI 96822, USA.
Water Sci Technol. 2004;50(1):27-32.
The soil environment in Hawaii is generally characterised as sub-optimal but permissive to support the in situ growth of E. coli and enterococci. However, soil desiccation and competition for nutrients by major indigenous soil microflora have been identified as potential factors that could limit a rapid and continual growth of faecal indicator bacteria in this soil environment. Despite these limitations, the genetic capacities of E. coli and enterococci are robust enough to enable these bacteria to become established as minor populations of Hawaii's soil microflora. Although the concentrations of E. coli and enterococci may have represented a fraction of the total soil microbiota, their presence in this habitat was very significant, for two important reasons: (a) soil was a major environmental source of E. coli and enterococci, and (b) the elevated counts of these bacteria in streams that routinely exceeded the EPA standards were due to run-off from soil. As a result, E. coli and enterococci were inadequate indicators to measure the degree of faecal contamination and potential presence of sewage-borne pathogens in Hawaiian streams.
夏威夷的土壤环境总体上被认为不太理想，但仍能支持大肠杆菌和肠球菌的原位生长。然而，土壤干燥以及主要本地土壤微生物对养分的竞争已被确定为可能限制粪便指示菌在这种土壤环境中快速持续生长的潜在因素。尽管存在这些限制，但大肠杆菌和肠球菌的遗传能力足够强大，使这些细菌能够在夏威夷土壤微生物群落中作为少数种群立足。虽然大肠杆菌和肠球菌的浓度可能只占土壤微生物群总量的一小部分，但它们在这个栖息地的存在非常重要，原因有两个：（a）土壤是大肠杆菌和肠球菌的主要环境来源，（b）这些细菌在溪流中的数量经常超过美国环境保护局的标准，原因是土壤径流。因此，大肠杆菌和肠球菌不足以作为衡量夏威夷溪流中粪便污染程度和污水传播病原体潜在存在的指标。
