Mitigation of low stream pH and its effects on salmonids.

摘要: Crushed limestone (200 tonnes) was spread in bars on the bed of an acidic brook (mean pH 5·0) Nova Scotia, Canada. A seasonally variable but significant increase running water resulted, and a longitudinal gradient over limed section extended to mouth brook. The effectiveness persisted after 3 years, during which downstream increased average 0·4 units (range <0·1–1·3 units) along with significantly Ca, Mg acid neutralizing capacity. Total exchangeable Al were not altered by non-exchangeable forms dominated. interstitial nearly neutral 7·1) beds it 5·4) gravel control upstream. Spawning Atlantic salmon (Salmo salar) dug three times more redds than control. Salmon fry survived they abundant density juvenile time, indicating recovery population. trout (Salvelinus fontinalis) also usually observed benefits for salmonids suggest that small-scale application stream spawning sites can be used mitigate effects low pH.