Researchers have noted the difficulties of conducting surveys, one of the most widely used techniques for collecting social science data, in minority communities. These difficulties include low response rates, interviewer bias, and the development of adequate sampling strategies to tap diverse segments within minority communities and locate specific segments of the population, such as male respondents. Efforts to minimize these difficulties in the implementation of an epidemiological, field‐based survey of 1,018 Black American adults are described.

Within one year of neutralizing Bowland Lake (pH 4.8–5.5 increased to 6.3–6.7), previously extensive growths of filamentous algae et (Mougeotia and Zygogonium, > 10 and 100% shoreline coverage, respectively) were essentially eliminated (< 1% shoreline coverage). Reacidification in the second year (pH 5.7–6.7) was accompanied by increased submerged epilithic and epiphytic growths of predominantly Zygogonium, often to preliming coverage. As found in other studies, pH [Formula: see text] appears to represent a threshold relative to the predominance of certain filamentous algae in softwater lakes. The short time between the change in acidity and the disappearance and reappearance of the filamentous algae suggests that they may be important biological indicators or predictors of acidification and its reversal. The changes in pH and alkalinity following neutralization did not substantially affect the macrophyte community in Bowland Lake. Macrophytes were restricted primarily to littoral areas less than 3 m in depth, despite excellent water transparency both before (SD = 8.0 m, 1982) and after neutralization (SD = 4.5 m, 1985). Two uncommon species observed prior to neutralization (Eleocharis parvula and E. acicularis) were not observed afterwards, while two new and uncommon species (Nitella sp. and Brasenea schreberi) were.

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