Appendix A. Environmental data for each study site and experimental period. See Notes for details.
Pond Max depth (m) Area (m2) pH Dissolved oxygen
(mg/L) Temp. (oC) Seston C:P (molar) Seston N:P (molar) Total chlorophyll a
(µg/L)Early season (June) P12 n.a. n.a. 6.90 6.01 25.3 416.7 105.8 5.27 P14 n.a. n.a. 6.92 6.00 25.5 488.7 143.0 8.65 P15 n.a. n.a. 7.05 11.30 25.8 437.1 53.3 6.47 Shaw4 n.a. n.a. 4.60 9.00 23.5 238.1 24.3 18.44 Lux16 n.a. n.a. 6.05 8.91 24.5 121.0 14.2 188.16Late season (August) P12 1.6 700 8.09 2.64 26.0 548.7 36.6 4.93 P14 1.6 700 8.22 5.52 26.0 439.6 34.9 7.25 P15 1.6 700 8.18 6.19 26.5 497.2 36.6 3.48 Shaw4 1.4 4208 5.30 0.28 25.0 498.8 36.6 72.38 Lux16 1.5 450 6.60 0.75 22.0 155.6 11.3 49.16
Algal size structure
relative abundance of chlorophyll a
per size class (%) Zooplankton biomass (mg/L) Pond <15m 15–60
µm >60
µm Total zooplankton Daphnia pulex Diaphanosoma brachyurumEarly season (June) P12 91.2 4.6 4.2 1.45E-01 4.51E-03 2.63E-02 P14 52.2 21.7 26.1 1.15E-01 5.10E-03 7.06E-02 P15 30.8 17.4 51.8 4.85E-01 1.57E-04 9.11E-02 Shaw4 15.4 38.5 46.1 8.15E-02 1.84E-02 2.10E-04 Lux16 20.1 61.7 18.2 1.20E-01 7.76E-02 0Late season (August) P12 38.7 33.1 28.2 1.24E-01 6.14E-04 6.06E-02 P14 60.2 4.5 35.2 2.20E-02 0 9.62E-03 P15 54.4 24.9 20.7 4.01E-01 0 7.43E-03 Shaw4 23.4 47.1 29.5 3.96E-03 0 1.70E-04 Lux16 19.7 11.7 68.6 1.80E-01 1.65E-01 0
Zooplankton biomass (mg/L) Pond Ceriodaphnia spp. Chydorus sphaericus Scapholeberis spp. Alona spp. Pleuroxus spp. Total small cladoceraEarly season (June) P12 1.15E-02 0 0 0 0 3.78E-02 P14 1.90E-03 7.21E-04 0 1.34E-05 0 7.33E-02 P15 1.34E-03 0 0 0 0 9.24E-02 Shaw4 1.51E-02 2.22E-02 2.35E-04 0 0 3.78E-02 Lux16 0 0 0 0 0 0Late season (August) P12 1.19E-02 2.36E-04 0 7.56E-08 1.33E-06 7.27E-02 P14 7.00E-05 4.50E-05 0 9.02E-06 2.06E-06 9.75E-03 P15 3.60E-03 4.56E-03 0 2.81E-06 6.87E-07 1.56E-02 Shaw4 3.36E-03 0 2.35E-04 0 0 3.76E-03 Lux16 2.46E-04 0 0 0 0 2.46E-04
Zooplankton biomass (mg/L) Pond Calanoid copepods Cyclopoid copepods Total rotifer Chaoborus americanus
(no./L) Chaoborus americanus
mean body mass
(mg/individual)Early season (June) P12 1.00E-01 2.01E-03 0 0.70 2.91E-02 P14 3.09E-02 2.07E-03 3.45E-03 1.66 1.74E-02 P15 3.38E-01 7.12E-03 4.78E-02 2.15 6.15E-03 Shaw4 2.81E-04 1.86E-02 6.42E-03 0.52 1.65E-03 Lux16 2.14E-02 1.88E-02 1.82E-03 4.11 6.87E-03Late season (August) P12 4.78E-02 2.52E-03 0 1.60 1.22E-02 P14 1.02E-02 2.08E-03 0 0.13 9.72E-03 P15 3.40E-01 4.55E-02 0 0.72 6.48E-03 Shaw4 0 1.93E-04 0 0.69 1.14E-02 Lux16 9.81E-04 6.27E-03 6.90E-03 6.33 5.38E-02
Chaoborus americanus size structure Density (L-1) per instar Relative abundance per instar (%) Pond Instar I Instar II Instar III Instar IV Instar I Instar II Instar III Instar IVEarly season (June) P12 6.01E+00 2.39E+00 9.41E-01 3.62E-01 61.9 24.6 9.7 3.7 P14 8.93E+00 2.72E+00 1.81E+00 0.00E+00 66.3 20.2 13.5 0.0 P15 0.00E+00 0.00E+00 0.00E+00 0.00E+00 91.5 7.8 0.0 0.8 Shaw4 0.00E+00 0.00E+00 0.00E+00 0.00E+00 91.7 8.3 0.0 0.0 Lux16 2.77E+00 2.08E-01 9.46E-02 0.00E+00 90.2 6.8 3.1 0.0Late season (August) P12 1.59E+00 9.70E-01 6.93E-02 0.00E+00 60.5 36.8 2.6 0.0 P14 0.00E+00 0.00E+00 0.00E+00 0.00E+00 50.0 50.0 0.0 0.0 P15 3.51E+00 8.26E-01 2.07E-01 0.00E+00 77.3 18.2 4.5 0.0 Shaw4 4.50E+00 1.04E+00 3.46E-01 0.00E+00 76.5 17.6 5.9 0.0 Lux16 6.94E+00 1.23E+01 8.01E+00 1.07E+00 24.5 43.4 28.3 3.8Notes: Limnological variables measured in the four study ponds during the early season (June 1999) and late season (August 1999) experimental periods. To determine biotic measures (zooplankton, Chaoborus, chlorophyll a, and seston C:N:P measures), water samples were taken at several points along a qualitative transect extending from pond edge to pond center and pooled to integrate spatial variation. Zooplankton and Chaoborus measures are means of two replicate samples. Abiotic variables (pH, temperature, and dissolved oxygen) were measured at mid-depth along the same transects and then averaged. Zooplankton biomass and Chaoborus body mass are dry weight estimates based on length-mass regressions. Seston C:N:P is based on the <35- µm fraction. Depth and area data were measured in July and August of 1998.