Comparison of plant community–environment relations in two estuarine marshes of northern British Columbia

Abstract

1989. Comparison of plant community-environment relations in two estuarine marshes of northern British Columbia. Can. J. Bot. 67: [146][147][148][149][150][151][152][153][154][155]. The Dala and Yakoun estuarine marshes in northern British Columbia were compared to evaluate similarities in species composition, plant communities, and vegetation-environment relationships. The Dala is a fjord-head marsh at the mouth of a glacially fed river with a fresh to brackish salinity regime and a 7-m tidal range. The Yakoun marsh is fed by lowland bog drainage on the Queen Charlotte Islands, has a salt to brackish salinity regime, and a 3-m tidal range. Both marshes contain similar dominant species (Carex lyngbyei, Deschc~tnpsia cespitosa, Porentilla paci'co, Triglocl~ir~ maririt?~utn), but share only about one third of the total (50) vascular species recorded. Four plant community types characterizing three main physiographic zones (low, intermediate, and high) were described at each marsh. Principal component analysis (PCA) of species composition data indicated similarities in general patterns of community organization at both marshes; however, PCA of soil chemical data indicated greater between-marsh differences, especially in intermediate and high zones. Canonical correlation analysis indicated that the Yakoun shows a closer connection between overall vegetation variation and substratum elevation, and a clearer elevational zonation of communities than the Dala. Examination of tidal regime data indicated that the Yakoun experiences steeper gradients in submergence time and flooding frequency than the Dala, thus offering an explanation for the different vegetation-elevation relationships. CAMPBELL, A,, et BRADFIELD, G. E. 1989. Comparison of plant community-environment relations in two estuarine marshes of northern British Columbia. Can. J. Bot. 67 : 146-155. Les marais d'estuaires Dala et Yakoun dans le nord de la Colombie-Britannique ont Ct C comparCs dans le but d'ivaluer les ressemblances dans la composition en espkces, les communautts vtgttales et les relations vCgttation-environnement. LeDala est un marais-fjord a l'embouchure d'une rivikre alimentCe par la glace et ayant un rCgime de salinitC allant de frais a saumitre et une portCe de marCe de 7 m. Le marais Yakoun, aliment6 par le drainage d'un markcage des basses terres des iles de la Reine Charlotte, a un regime de saliniti allant de sale h saumitre et une portte de marCe de 3 m. Les deux marais abritent des espkces dominantes semblables (Carex lyngbyei, Descharnpsio cespirosa, Porentilla pac@ca, Triglochin maritimurn), mais ne partegent qu'environ un tiers du nombre total (50) d'espkces vasculaires nottes. Quatre types de communautCs vtgttales qui caracttrisent trois zones physiographiques principales (basse, intermediaire et haute) ont t t C dCcrites i chaque marais. Une analyse en composantes principales (ACP) des donntes sur la composition en espkces a indiqut des ressemblances dans les patrons gCnCraux de I'oganisation des communautCs dans les deux marais; c...

Interpreting ecological patterns in an intact estuary, South‐west New Zealand World Heritage Area

“…Our objective sampling method was to use restricted randomization of plots placed along a series of restricted randomised transects orientated at right angles to the water margins and low tide line. Similar approaches have been applied in comparable studies of estuarine ecology overseas where the aim was to follow gradients of estuarine features and associated environments (Disraeli & Fonda, 1979; Bradfield & Porter, 1982; Hutchinson, 1982; Dawe & White, 1986) but these studies differ from ours in both their scale and in the degree of subjectivity used (Campbell & Bradfield, 1989).…”

“…A comparative study of two estuarine marshes of different tidal range (7 m and 3 m) in northern British Columbia indicated the importance of the tidal magnitude in distinguishing zonal vegetation patterns and also in the enhancement of the correlation between vegetation zones and elevation (Campbell & Bradfield, 1989). Similarly, elevation as it affected tidal inundation, was also the main determinant of community pattern in the Nanoose‐Bonell Estuary on the east coast of Vancouver Island, British Columbia (Dawe & White, 1986), though not all communities here were significantly different in their elevation.…”

Stepwise canonical discriminant analysis of continuous digitalized signals: Application to chromatograms of wheat proteins

“…The gravity centres of the 15 genotypes of the verification set were estimated on Y,,,, giving the matrix P,,,. The discriminant scores of the observations of the verification set and those of their gravity centres were then assessed similarly to (13) and (14) applied on Y,,, and P,,,. The observations of the verification set were then tentatively reclassified in their group of genotype using the Euclidean distance as in (8).…”

Vegetation patterns and environmental gradients in coastal meadows on the Yukon–Kuskokwim delta, Alaska

“…Salt marsh zonation is influenced by frequency and duration of tidal inundation, elevation above sea level, fluvial erosion, deposition of sediments, soil salinity, drainage, soil moisture, and depth to underlying permafrost (Kershaw 1976;Peterson and Billings 1980;Hutchinson 1982;Ewing 1983;Vince and Snow 1984;Bradfield and Campbell 1986;Campbell and Bradfield 'Author to whom all correspondence should be addressed.…”