TABLE 2.

Physicochemical data for the two acid mine drainage sites from which streamer biofilms were obtained

ParameterMynydd ParysaTrefriw Wells Spab
Feed pipePoolDrain 1Drain 2
pH2.7/2.42.72.62.92.5
Temp (°C)8.8/12.410.19.89.513.3
Eh (mV)420/526657670813712
Conductivity (μS/cm)2,994/3,1601,5501,5201,6401,520
Dissolved oxygen concn (mg liter−1)0.55/1.40.60.9 (0.5)1.63.9
Dissolved organic carbon concn (mg liter−1)6.0/6.94.54.312.28.0
Fe2+ concn (mg liter−1)473/5202181932214
Fetotal concn (mg liter−1)514/NDc22325910041
SO42− concn (mg liter−1)1,552/1,846NDNDNDND
Mn concn (mg liter−1)5/ND1.11.1ND1.5
Cu concn (mg liter−1)35/ND<1<1ND<1
Zn concn (mg liter−1)50/ND<1<1ND<1
  • a Data for 1 February 2002/data for 24 July 2002.

  • b The feed pipe and drain 1 data are data for 12 March 2004; the pool and drain 1 data are data for 3 April 2003. Most of the pool data are data for water taken from the top 1 m of the pool; the only exception is the dissolved oxygen value in parentheses, which is the value for water at the base (“benthic zone”) of the pool.

  • c ND, not determined.