Appendix 5.2-1 - People.stat.sfu.ca - Simon Fraser University

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measurements in 2010. The within-year timing of the samples was divided into early(June or earlier) or late (July or later) sampling seasons.1.2 MarineThree locations were monitored, one of which is treated as the reference site. Oneof the Project sites (RBE) has been monitored since 2004; the second Project site(RBW) has been monitored since 2009; the reference site (REF-AEMP) has also beenmonitored since 2009.Historical samples were usually collected in surface layer or mid-column.Occasionally, historical marine samples were collected from the lower layer of thewater column or just above the sediment, but these samples were excluded from theanalysis because 2010 samples were only collected from the surface layer.The within-year timing of the sample was divided into early (June or earlier) or late(July or later) sampling seasons. The reference site was only sampled in the lateseason in all years.Many of the detection limits in 2010 were higher than in past years with most readingsfor several parameters now below detection limits. This will make it difficult todetect any Project impacts in 2010.1.3 LakesLakes were divided into large and small lakes and a separate analysis is done for eachsize category.1.3.1 Small LakesOnly two lakes were monitored in the small lake category with the Project lake (LittleRoberts Lake) being monitored since 1995, but the reference lake (Reference Lake D)only monitored in 2010. Unfortunately, this will severely limit the analyses that canbe done for this size category. All historical and 2010 samples collected in the smalllakes were collected from either the surface or middle of the water column.The within-year timing of the sample was divided into early (June or earlier) or late(July or later) sampling seasons.1.3.2 Large LakesThe large lake category included two Project lakes and one reference lake. OneProject lake (Doris Lake North) was monitored in 1995 and then from 2003 onwards;the second Project lake (Doris Lake South) was only monitored in 1995 and then in2009 and 2010; the reference lake (Reference Lake B) was monitored only in 2009 and2010.2
Historical data were collected from two depth strata: Surface and Deep. Somesamples from 1995 had an unknown depth zone and these were classified also ascoming from the surface. Both zones were sampled in 2009 and 2010 in all lakes, butonly surface water was sampled in 1995 and 2003 in the Project lakes. Because therewas little evidence of vertical chemical stratification, samples from all depths wereincluded in the analysis, and no depth effect was introduced in the analysis.The within-year timing of the sample was divided into early (June or earlier) or late(July or later) sampling seasons.2. Analysis Methods2.1 AssumptionsThere are several assumptions made for the analyses in this section. The keyassumption is that the samples taken are a random sample of the body’s water qualityfor that monitoring period (e.g., for that month in that year when measured) and ofthe sampling location. There is no way to assess this assumption other than by acareful consideration of the landscape and sampling protocol.Another necessary assumption is that missing data (e.g., a stream was not measuredin a month in a particular year) is missing completely at random (MCAR) so that thereis no information about the water quality from the “missingness”. This assumptioncould be violated if, for example, samples were not taken because it was known thatwater quality was compromised on the selected sampling date. There is no way toassess this assumption except by carefully considering why data was not collected ona particular date. If, for example, data were not collected because the sampling vialbroke in transit, this is likely a case of MCAR.It is further assumed that the water columns of all sampled waterbodies arecompletely mixed so that depth effects can be ignored. This assumption was verifiedby examining the raw sample means at various depths, and fitting statistical modelsto examine the effects of depth, and few depth effects were seen.2.2 Replicate samplesReplicate samples collected within the same day and at the same depth are treatedas pseudo-replicates (Hurlbert, 1984) and values are averaged before furtheranalyses. This will be an approximate analysis (compared to actually modellingreplicated values as nested within a particular day), but given the high variabilityseen for most of the readings, the reported results should be insensitive to thisaveraging.3
Page 1: Analysis of water quality data coll
Page 6 and 7: presented in this report because of
Page 8 and 9: censoring) in all streams where dat
Page 10 and 11: Table Stream-1. Summary of the prop
Page 12 and 13: Table Stream-2. Summary of potentia
Page 14 and 15: Table Steam-3. Summary of test for
Page 16 and 17: Table Stream-4. Summary of BACI com
Page 18 and 19: Table Marine-2. Summary of potentia
Page 20 and 21: Table Marine-3. Summary of test for
Page 22 and 23: Table Slake-1. Summary of thepropor
Page 24 and 25: Table Slake-2. Summary of potential
Page 26 and 27: Table Slake-3. Summary of test for
Page 28 and 29: Table Llake-1. Summary of the propo
Page 30 and 31: Table Llake-3. Summary of test for
Page 32: Table Llake-4. Summary of BACI comp

Appendix 5.2-1 - People.stat.sfu.ca - Simon Fraser University

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