Influence of Surface Water Mineral Nutrition on the Plasticity of Sarracenia purpurea in Sphagnum fens, Marl Wetlands, and Sand Savannahs

Abstract

Sarracenia purpurea, the northern pitcher plant, inhabits three very different wetland habitats throughout its range: two acidic, low nutrient wetland types (Sphagnum and sand substrate-based) and one alkaline wetland type (marl substrate-based) located primarily within the Great Lakes region. This study attempted to classify the nutrient status of the rarer marl wetlands in relation to the acidic Sphagnum and sand substrate-based wetlands and to examine the morphology of S. purpurea growing in these wetland types. S. purpurea has previously shown morphological variation in response to nutrient availability but also in response to environmental changes unrelated to nutrient concentrations. We sampled water chemistry and plant morphological variation within the three distinct habitat types. Marl wetlands, regardless of significantly higher pH levels, were characterized by over all low nutrient concentrations with high levels of calcium (mg Ca/L) and sulfate (mg S/L). S. purpurea plants growing in high calcium concentrations showed reduced flower heights and leaf lengths. All sampled wetland types showed low overall nutrient concentrations, regardless of pH with S. purpurea plasticity partially influenced by wetland-specific water chemistry.