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Soil & Water Conservation Society of Metro Halifax (SWCSMH)
Mackie, G.L., Hincks, S., and Barker, D. 2000. Introduction to Aquatic Environments, Course Manual, Univeristy of Guelph. 11 chapters, 5 appendices., and
Mackie, G.L. 2001. Applied Aquatic Ecosystem Concepts. Kendall/Hunt Publishing Company. xxv, 744 pp. ISBN 0-7872-7490-9.
Mackie, G.L. 2004. APPLIED AQUATIC ECOSYSTEM CONCEPTS. Second Ed. Kendall/Hunt Publishing Company. 784pp. ISBN 0-7575-0883-9
Mean diversity d= -Σ(ni/N * log2 ni/N), where ni= number of specimens in species i and N= total number of specimens in sample.
Features Oligotrophic lakes Mesotrophic lakes Eutrophic lakes Lake basin shape U-shaped Deep V-shape Shallow V-shape Mean depth Very deep Moderately shallow Usually shallow Hypolimnion temperature 4° C About 4° C Usually >4° C Hypolimnion volume Large Moderately small Small Thermocline depth High Moderately deep Shallow Secchi depth >5 m 3-5 m <3 m Dissolved oxygen profile Orthograde Clinograde Clinograde RAHOD
mg O2/m²/day<0.017 0.017-0.033 >0.033 Dissolved oxygen content 90-100% in hypolimnion 25-90% in hypolimnion <25% in hypolimnion Calcium content Low
(usually <10 mg/L)Moderate
(10-25 mg/L)High
(>25 mg/L)Total nitrogen content <300 µg/L 300-600 µg/L >600 µg/L Total phosphorus <10 µg/L 10-30 µg/L >30 µg/L Chlorophyll a <2 µg/L 2-5 µg/L >5 µg/L Macrophyte diversity Many submerged spp. but low biomass, few/no floaters, emergents Many submerged, floating & emergent spp. & high biomass Few submerged sp; many floaters, emergents with high biomass Profundal benthic diversity High diversity
(Log2) >3Moderate diversity
(Log2) =1-3Low, mean diversity
(Log2) <1Profundal indicator species Pisidium conventus, Sphaerium nitidum, Tubifex kessleri, Peloscolex variegatum, Diporeia hoyi, Mysis relicta, Hexagenia limbata Several tubificid spp., Pisidium casertanum, Sphaerium corneum, Caecidotea (Asellus) spp., several chironomid spp. Tubifex tubifex, Limnodrilus hoffmeisteri, Chironomus plumosus Profundal fish diversity Many salmonids, white fish and cottids A few salmonids & cottids, walleye, pike, bass, gizzard shad abundant Coarse fish (perch, carp, suckers, minnows) or none
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