Hidrológiai Közlöny 1967 (47. évfolyam)

7. szám - A „Szervesanyag meghatározási problémák édesvizekben” című 1966. szeptember 25–28. között Tihanyben rendezett Szimpózium előadásai - Wetzel, Róbert G.: Oldott organikus vegyületek két indiánai tóban

Wetzel, R. G.: Oldott organikus vegyületek Hidrológiai Közlöny 1967. 7. sz. 301 Table 1. Concentrations and bacterial utilization ot galactose and fructose in Crooked Laké, Indiana Compound Date Depth [m] i—i bo a i &p i c H 1 1 QE o Sí Galactose 9 VII 04 25 9.0 0.56 171 13 VII 04 25 0.7 0.25 447 7 VIII 04 2.5 1.7 0.78 22 7 11.3 1.28 88 15 0.5 1.12 58 25 47.1 1.04 453 30 10.5 1.95 54 20 IX 04 1 6.5 0.88 74 30 5.2 0.54 96 30 X 04 1 16.0 0.38 421 30 30.1 0.60 502 28 XI 04 1 34.3 0.44 780 30 49.3 0.73 675 Fructose 13 VII 04 25 15.2 0.34 447 12 VIII 64 2.5 15.4 1.59 97 7 15.3 1.26 121 15 8.6 0.19 453 25 12.0 0.32 375 30 11.8 1.12 132 20 IX 64 1 25.9 1.54 168 30 18.4 0.65 283 30 X 64 1 28.9 0.85 340 30 13.1 0.33 40 27 XI 64 1 28.8 0.69 417 30 51.0 0.80 638 Table 2. Concentrations and bacterial atilization of glucose, acetate, galactose, and fructose in Liltle Crooked Laké, Indiana Compound Date Depth [m] 7 M g s^ '—

1 i tx i—i 7Glucose 24 VI 64 4 35.5 8.1 44 29 VI 64 12 37.8 1.6 232 9 VII 64 12 97.3 9.4 104 21 VIII 64 1 30.6 8.5 36 l 68.3 4.0 171 14 48.6 4.7 104 25 IX 64 1 48.0 8.9 54 14 69.6 3.1 222 Acetate 30 VI 64 3 34.9 5.0 68 12 51.1 2.7 193 21 VIII 64 1 26.3 6.0 44 7 31.8 13.3 24 14 15.4 1.6 98 25 IX 64 1 59.2 5.4 109 14 79.5 4.2 190 Galactose 9 VII 64 12 13.7 1.4 100 26 VIII 64 1 62.4 3.9 160 7 38.8 1.8 222 14 47.7 2.4 193 Fructose 26 VIII 64 1 20.6 2.2 93 7 12.6 0.8 150 14 18.3 1.1 168 portant, the natural periods of substrate regeneration were consistently low in contrast with turnover times for Croóked Lake. Tlie verticai distribution of substrate concentrations and rates of heterotrophic utilization exhibited a marked stratification that persisted for several months. During thermal stratification, levels of glucose, galactose, and acetate in the deeper Crooked Lake increased markedly in the metalimnion (6—10 meters) from relatively low epilimnetic concentrations (Fig. 1 and 3). Except for galactose the concentrations decreased sharply below the metalimnion to relatively constant levels in the hypolimmon. Sharp increases were commonlv observed near the sediment-water interface. Levels of fructose were low and exhibited little verticai variation. The theoretical maximum velocity of uptake (F, heterotrophic capacity) in Crooked Lake responded in a generál way to substrate concentrations (Fig. 1, 2, and 3). Particularly noticeable is the area of low uptake of acetate and, to a lesser extent, glucose, galactose, and fructose, in the upper strata of the hypolimmon. Uptake velocities of acetate increase markedly above the sediments in the lower strata of the hypolimnion. Substrate turnover times correlate inverselv with uptake velocities, especially in the case of acetate, where regeneration times decreased markedly in the lower hypolimnion during thermal stratification. As one would anticipate, all parameters were relatively uniformlv distributed with depth during vernal overturn in late November and earlv December. The verticai distribution of the organic substrates and bacterial utilization followed a similar pattern in the more productive Little Crooked Lake (Fig. 4, Table 2). Concetrations of glucose and acetate increased in the metalimnion (4—7 meters); those of galactose and fructose decreased slightly in the same region. L

Ttilization velocities of glucose, galactose, and fructose decreased significantlv below the epilímnetic waters; acetate uptake reached its highest levels in the lower matalimnion. As in Crooked Lake, turnover times generally varied vertically inverselv with uptake velocities.