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Cyclotella sp.

46 British Columbia (Canada) lakes

Soil & Water Conservation Society of Metro Halifax (SWCSMH)

July 26, 2006   Paleolimnology Homepage

Excerpts from:

Hall, R.I., and Smol, J.P. 1992. A weighted-averaging regression and calibration model for inferring total phosphorus concentrations from diatoms in British Columbia (Canada) lakes. Freshwater Biology. 27:417-434


Img-pin.gif  Conclusions/Summary
Img-Blue_Arrow11F3.gif  Kamloops Lake, an interesting application

Img-pin.gif  Study area and lake selection
Img-Blue_Arrow11F3.gif  Data screening

Img-pin.gif  Diatom inference model


  1. The relationship between surficial sediment diatom taxa (Bacillariophyceae) and measured limnological variables in 46 British Columbia lakes was explored using canonical correspondence analysis (CCA). Lake-water [TP] concentration, maximum lake depth, conductivity, and calcium concentration each accounted for independent and statistically significant directions of variation in the distribution of diatom taxa.

  2. Weighted-averaging (WA) models were developed to infer lake-water TP from the relative abundances of 131 diatom taxa in the surficial sediments of 37 lakes. WA regression and calibration with classical deshrinking provided the best model for TP reconstructions.

  3. The quantitative inference model has two major advantages over existing multiple linear-regression models:
    1. inferences were based on the responses of individual taxa to TP, and do not involve grouping the taxa into a small number of ecological categories; and
    2. the model assumes that diatoms respond to TP in a unimodal, rather than a linear, fashion.

  4. The WA model can now be used to infer past lake-water TP, within the range 5-28 µg.l-1, from diatoms preserved in the sediments of British Columbia lakes. The model can provide quantitative estimates of the onset, rate, and magnitude of lake eutrophication in response to natural processes and human disturbances.

Kamloops Lake, an interesting application of the model:

Study area and lake selection

Lake eutrophication is severe in some areas of British Columbia as a result of intensive agriculture (e.g., cattle ranching), and industrial and saw-mill activity. These human activities often impair the quality of drinking water and adversely affect the production of salmonid fishes.

The topography, geology, climate, vegetation and soils of British Columbia are extremely heterogenous, and the lakes display a similarly broad range of physical, chemical, and biological characteristics. This study included 46 freshwater lakes (with well-preserved surficial sediment diatom assemblages) distributed predominantly in the southern half of the province. The lakes were specifically chosen to reflect a broad trophic gradient, and they spanned a wide range of TP (5-85 µg.l-1). In order to minimize the influence of pH and pH-related variables on the distribution of diatom taxa, lakes were selected to include a relatively narrow pH range (7.5-8.5). The study area included four biogeoclimatic zones (Interior Douglas Fir, Coastal Douglas Fir, Interior Western Hemlock, and Cariboo Aspen-Lodgepole Pine). These zones are defined primarily in terms of temperature and precipitation, but also differ in vegetation and soil types.

Data screening:

Diatom inference model

Table: Total phosphorus optima and number of occurrences for the 131 diatom taxa included in the weighted-averaging model. Taxa with numbers followed by `BC' are taxa of unknown taxonomic position that were retained as distinct in this study. The taxa numbers in the first column are based on ascending TP optimum. In other words, No. 1 taxon has the lowest TP optimum (6.8 µgl-1), whereas the No. 131 taxon has the highest TP optimum (23.3 µgl-1)

No.Diatom taxonTP
Number of
47Achnanthes biasolettiana Grun.10.516
4Achnanthes bioreti Germ.7.33
73Achnanthes clevei Grun.11.717
23Achnanthes conspicua A. Mayer9.321
124Achnanthes delicatula (Kütz.) Grun.18.64
87Achnanthes detha Hohn & Hellerman12.214
97Achnanthes exigua Grun.12.724
96Achnanthes exigua var. heterovalva Krasske12.621
89Achnanthes lanceolata (Bréb. ex Kütz.) Grun.12.319
94Achnanthes lanceolata var. dubia Grun.12.618
110Achnanthes lanceolata var. elliptica Cleve14.315
2Achnanthes levanderi Hust.6.93
25Achnanthes linearis (W. Smith) Grun.9.314
14Achnanthes microcephala (Kütz.) Cleve8.89
20Achnanthes minutissima Kütz.9.027
49Achnanthes pinnata Hust.10.74
60Achnanthes suchlandtii Hust.11.27
59Amphora libyca Ehrenb. ex Kütz.11.223
12Amphora parallelistriata Manguin8.43
44Amphora pediculus (Kütz.) Grun. ex A. Schmidt10.432
31Amphora thumensis (Mayer) Krieger9.712
3Anomoeoneis vitrea (Grun.) R. Ross7.38
79Asterionella formosa Hasall11.825
74Asterionella ralfsii W. Smith11.74
120Aulacoseira ambigua (Grun.) Simonsen 16.918
6Aulacoseira distans (Ehrenb.) Simonsen7.810
27Aulacoseira distans var. nivalis (W. Smith) Kirchner9.53
131Aulacoseira granulata var. angustissima (O. Müll.) Simonsen23.32
105Aulacoseira italica ssp. subarctica (O. Müll.) Simonsen13.213
53Aulacoseira italica var. tenuissima (Grun.) Simonsen11.011
15Aulacoseira lirata (Ehrenb.) R. Ross8.93
116Aulacoseira lirata var. lacustris (Grun.) R. Ross15.86
26Aulacoseira perglabra var. floriniae Camburn9.34
107Aulacoseira undulata (Ehrenb.) Kütz.13.74
1Aulacoseira sp. 12 PIRLA6.82
69Cocconeis diminuta Pant.11.621
100Cocconeis placentula Ehrenb.12.98
109Cocconeis placentula var. euglypta (Ehrenb.) Grun.14.08
85Cocconeis placentula var. lineata (Ehrenb.) Van Heurck12.110
122Cyclostephanos sp. 1 BC17.53
75Cyclotella bodanica Grun.11.726
42Cyclotella bodanica var. affinis Grun.10.216
61Cyclotella cf. radiosa (Grun.) Lemm.11.33
5Cyclotella comensis Grun.7.47
106Cyclotella kuetzingiana Thwaites13.611
8Cyclotella kuetzingiana var. planetophora Fricke7.92
10Cyclotella kuetzingiana var. radiosa Fricke8.35
16Cyclotella meneghiniana Kütz.9.02
35Cyclotella michiganiana Skvortzow10.119
111Cyclotella ocellata Pant.14.58
32Cyclotella stelligera (Cleve & Grun.) Van Heurck9.724
18Cymbella cesatii (Rabenh.) Grun.9.02
11Cymbella delicatula Kütz.8.37
24Cymbella diluviana (Krasske) M.B. Florin9.37
71Cymbella microcephala Grun.11.616
38Cymbella minuta Hilse ex Rabenh.10.214
98Denticula elegans Kütz.12.76
21Diatoma hiemale var. mesodon (Ehrenb.) Grun.9.25
54Diatoma tenue var. elongatum Lyngb.11.07
117Epithemia argus (Ehrenb.) Kütz.16.49
36Fragilaria brevistriata Grun.10.136
104Fragilaria brevistriata var. capitata Hérib13.26
91Fragilaria brevistriata var. elliptica Hérib12.315
40Fragilaria brevistriata var. inflata (Pant.) Hust.10.222
86Fragilaria capucina var. mesolepta (Rabenh.) Rabenh.12.29
119Fragilaria construens (Ehrenb.) Grun.16.628
88Fragilaria construens var. binodis (Ehrenb.) Grun.12.312
82Fragilaria construens var. venter (Ehrenb.) Grun.12.034
108Fragilaria crotonensis Kitton13.921
78Fragilaria lapponica Grun.11.828
113Fragilaria pinnata Ehrenb.15.036
65Fragilaria pinnata var. intercedens (Grun.) Hust.11.421
84Fragilaria pinnata var. lancettula (Schum.) Hust.12.128
63Fragilaria vaucheriae (Kütz.) J.B. Petersen11.48
7Fragilaria virescens var. exigua Grun.7.82
58Fragilaria sp. 1 BC11.216
46Fragilaria sp. 2 PIRLA10.414
29Fragilaria sp. 3 PIRLA9.53
33Fragilaria sp. 4 PIRLA9.97
57Gomphonema angustatum (Kütz.) Rabenh.11.16
13Gomphonema angustum Agardh.8.64
39Gomphonema parvulum (Kütz.) Kütz.10.24
129Gomphonema subtile Ehrenb.21.53
127Gyrosigma acuminatum (Kütz.) Rabenh.20.63
34Mastogloia smithii Thwaites ex W. Smith10.06
115Navicula absoluta Hust.15.211
99Navicula cari Ehrenb.12.813
51Navicula cryptocephala Kütz.10.812
48Navicula explanata Hust.10.52
41Navicula laevissima Kütz.10.212
52Navicula minima Grun.10.917
102Navicula pseudoventralis Hust.12.916
83Navicula pupula Kütz.12.117
43Navicula radiosa Kütz.10.39
121Navicula scutelloides W. Smith ex Greg.17.38
95Navicula seminuloides Hust.12.616
77Navicula shadei Krasske11.86
45Navicula subminiscula Manguin10.413
92Navicula submuralis Hust.12.515
22Navicula utermoehlii Hust.9.26
125Navicula ventralis Krasske18.74
80Navicula vitabunda Hust.11.819
9Neidium ampliatum (Ehrenb.) Krammer8.01
76Nitzschia denticula Grun.11.713
67Nitzschia fonticola Grun.11.521
130Pinnularia braunii (Grun.) Cleve21.62
126Pinnularia nodosa (Ehrenb.) W. Smith20.63
55Rhopalodia gibba (Ehrenb.) O. Müll.11.05
128Stauroneis anceps Ehrenb.21.06
30Stauroneis phoenicenteron (Nitzsch) Ehrenb.9.66
62Stephanodiscus alpinus Hust.11.313
68Stephanodiscus cf. vestibulis Hĺkansson, Theriot, & Stoermer11.62
118Stephanodiscus cf. pseudoexcentricus Hĺkansson & Stoermer16.53
93Stephanodiscus hantzschii Grun.12.513
101Stephanodiscus hantzschii fo. tenuis (Hust.) Hĺkansson & Stoermer12.95
56Stephanodiscus medius Hĺkansson11.010
90Stephanodiscus minutulus (Kütz.) Cleve & Möller12.324
112Stephanodiscus niagare Ehrenb.15.014
66Stephanodiscus parvus Stoermer & Hĺkansson11.412
103Stephanodiscus sp. 1 BC13.01
19Stephanodiscus sp. No. 5 BC9.02
72Synedra cyclopum Brutscy11.711
64Synedra delicatissima Grun.11.43
70Synedra filiformis var. exilis Cleve-Euler11.65
81Synedra minuscula Grun.12.01
37Synedra parasitica (W. Smith) Hust.10.115
17Synedra radians Kütz.9.02
50Synedra ulna var. chaseana Thomas10.84
28Tabellaria fenestrata (Lyngb.) Kütz.9.52
123Tabellaria flocculosa str. III sensu Koppen17.67
114Tabellaria flocculosa str. IIIp sensu Koppen15.17

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