Theresa, You may consider standardizing your data set with some informed assumptions of the water chemistry by first modeling individual systems with a program such as PHREQ (free from USGS). This may allow you to identify some reasonable concentrations for missing parameters at some of the sites and provide a better comparison between them.
Peter ************************************************** Peter Kirchner, Graduate Research Scientist Sierra Nevada Research Institute University of California, Merced [email protected], (209) 834-7628 -----Original Message----- From: Ecological Society of America: grants, jobs, news [mailto:[email protected]] On Behalf Of Theresa Hughes Sent: Saturday, March 14, 2009 11:25 AM To: [email protected] Subject: [ECOLOG-L] multivariate analysis of acid mine drainage I would appreciate any advice or suggestions for performing multivariate analysis on the mean contaminant concentrations of ~100 different mine drainages. The key parameters are pH, sulphate, Fe(II), Fe(III), Al, Mn, Cu, Zn, Pb, Ca, and CO3, but I am considering other parameters as well. Available datasets are quite varied, which is limiting the number of useful parameters. My objective is to identify major groupings within the drainages, as well as to identify the most significant variables. Many thanks, Theresa Hughes Trinity College Dublin Dublin, Ireland _________________________________________________________________ Get 30 Free Emoticons for your Windows Live Messenger http://www.livemessenger-emoticons.com/funfamily/en-ie/
