Patterns in Nutrient Availability and Plant Diversity of Temperate North American Wetlands

Abstract

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The Relation Between Unpalatable Species, Nutrients and Plant Species Richness in Swiss Montane Pastures

“…This hypothesis may therefore explain the positive relationship between soil N:P ratio and plant species richness in our study as N:P ratios were lower than 11 suggesting N limitation. The lack of any relationship between species richness and soil N:P ratio reported by Bedford et al (1999) may have been due to the fact that the N:P ratios in their study ranged from 5 to 45.…”

Formation of tussocks by sedges: effects of hydroperiod and nutrients

“…Topsoil was slightly basic (pH 7.73 6 0.07) with low organic-matter content (2.3% 6 0.00%), total N (0.12% 6 0.0000%) and P (0.0028% 6 0.0003%), relative to 12 mineral-soil wetlands reviewed by Bedford et al (1999). The topsoil had moderate levels of K (0.0131% 6 0.0010%) and high levels of Ca (0.2071% 6 0.0035%) and Mg (0.0625% 6 0.0005%), compared to typical agricultural soils (UW-Madison Soil Plant Analysis Laboratory).…”

Nitrogen availability alters the expression of carnivory in the northern pitcher plant, Sarracenia purpurea

“…N concentrations were chosen to bracket measured rates of annual deposition (determined from United States National Atmospheric Deposition Program data). P concentrations also were varied to determine whether plants responded to N limitation directly or to P limitation caused by increased N availability (26). Growth of bog plants may be limited by either N or P (26); growth of S. purpurea appears to be colimited by N and P (median N͞P ϭ 15.5; range ϭ 10.15-39.32; n ϭ 31 adult plants; N and P concentrations of dried, ground plant tissue determined with a Perkin-Elmer Autoanalyzer).…”