Lake Water and Sediment

Abstract

Sixteen lakes are described, varying in geology and all but two of low productivity, and including three acid bog types. A method is described for indirect estimation of the sum of Na and K. In lakes generally, low pH is related to low conductivity, but in these coastal lakes the Na in ocean spray keeps up the conductivity even in very acid waters. At equilibrium the inorganic P in solution is 2–3 ppb and represents a residual soluble fraction, independent of productivity and pH. Total P is 10–15 ppb and the concentration is not related to productivity. There is an annual cycle of inorganic P with a winter maximum, spring decline, and summer minimum. Methyl orange alkalinity varies directly with the sum of Ca and Mg and with either of the ions separately. The scatter in the regression of alkalinity versus Mg is greater than that of alkalinity versus Ca. There is a reduction of per cent organic material in the sediments directly related to increasing alkalinity. The cause is attributed to greater bacterial activity as the pH goes up.