The ecology of Potamogeton species in central North America

Abstract

The distribution of 17 Potamogeton species was examined at 430 sites in central North America with respect to water body type, bottom substrate and 8 water chemistry parameters (pH, total dissolved solids, total alkalinity, chloride, sulphate, phosphorus, combined nitrate and nitrite, and dissolved organic matter). All except 2 of the species showed statistically significant distributions with respect to some of the environmental parameters examined. Each species occupied a different combination of chemical parameter ranges. The species formed a distribution spectrum with respect to water chemistry, with 19 epihydrus and R obtusifolius frequenting low inorganic concentrations at one end of the scale, and I! Jiliformis, I? pectinatus and p vaginatus at the other end, these species characterized by high mean inorganic values and occurring most often in saline or alkaline habitats. While 41 significant positive interspecific associations were found within the genus in lentic waters, only 4 were apparent in lotic habitats.Potamogeton species richness (PR) was related to water body and bottom type, with lakes and sand bottoms showing the highest mean PR values. Stepwise multiple regression analysis showed that, in the area as a whole, the water chemistry parameters examined accounted for ~25% of the observed variability in PR. The relative importance of individual chemical parameters in relation to PR varied in different water body types.

Niche congruency of aquatic macrophytes in central North America with respect to 5 water chemistry parameters

“…Members of the genera Chara, Sparganium, Callitriche and Sagittaria (except S. rigida) were grouped together respectively because of the difficulty of identifying individual species when reproductive structures were frequently absent. The mean, maximum and minimum values at which the macrophytes were observed are given in Table 1; data for the genus Potamogeton have been presented elsewhere (Pip, 1987c for mean niche positions ( Fig. 1) with respect to the 5 parameters reflected the locations in the ecological tolerance ranges where each macrophyte taxon was most often found.…”

“…For example, P! obtusifolius and P epihydrus, members of the same cluster, show different proportions of lentic and lotic habitats (Pip, 1987c). P gramineus, P zosteriformis and P praelongus, members of another group, all prefer lacustrine habitats (Pip, 1987c) but show dissimilar depth ranges where they occur together (Pip and Sutherland-Guy, 1987).…”

“…The study area and the proportions of different water body and bottom substrate types have been described previously (Pip, 1987c). All sites contained water year-round.…”

Aquatic macrophyte composition in relation to environmental factors of irrigation ponds around Lake Shinji, Shimane, Japan

“…Comparative studies of aquatic vegetation between stagnant water bodies have long been attracting many investigators (Hutchinson 1975), and the correlations between species occurrence and environmental factors have been examined in many geographical regions (Fassett 1930;Moyle 1945;Swindale & Curtis 1957;Spence 1967;Collins & Likens 1969;Seddon 1972;Crowder et al 1977;Wiegleb 1978;Jenstn 1979;Pip 1979Pip , 1984Pip , 1987Pip , 1988Hellquist 1980;Felzines 1982;Kadono 1987a;Hamashima 1983a, b;Kerekes et al 1984;Catling etal. 1986;Jackson & Charles 1988).…”

Water, Sediment and Macrophyte Quality of Some Shrimp Culture Ponds and Freshwater Ecosystems of Koyra

“…Zannichellia palustris was recorded only in the shrimp culture ponds and which is indicating that this plant only can grows in saline habitats. Sahai and Srivastava (1976), Kulshreshtha and Gopal (1981), Kulshreshtha (1982), Purohit and Singh (1985), and Pip (1987) observed in their studies that Ceratophyllum sp., Limnophylla heterophylla, Ludwigia sp., Marsilea quadrifolia, Nymphoides sp., Ottelia sp., Pistia sp., Salvinia sp. and Utricularia sp.…”