Edaphic limitations to growth and photosynthesis in Sierran and Great Basin vegetation

• Published in: Oecologia 1989-02, Vol.78 (2), p.184-190
• Main Authors: DeLucia, E.H, Schlesinger, W.H, Billings, W.D
• Format: Article
• Language: English
• Subjects: Acid soils; Agricultural soils; altered soil; Animal and plant ecology; Animal, plant and microbial ecology; Artemisia tridentata; Autoecology; Biological and medical sciences; Bromus tectorum; Conifers; Desert soils; Forest soils; Fundamental and applied biological sciences. Psychology; great basin and pacific slope; growth; Nitrogen; Phosphorus; Photosynthesis; Pinus jeffreyi; Pinus monophylla; Pinus ponderosa; Plant growth; Plants; Plants and fungi
• ISSN: 0029-8549; 1432-1939
• DOI: 10.1007/BF00377154

Soils derived from hydrothermally altered andesite support unique communities of Sierran conifers (Pinus ponderosa Laws. and P. jeffreyi Grev. and Balf.) amongst sagebrush (Artemisia tridentata Nutt.) vegetation in the western Great Basin. Plants grown in soil derived from hydrothermally altered bedrock had lower growth rates, total biomass, and net photosynthetic rates than plants grown in soil derived from unaltered andesite of the same formation. Total dry mass was 10 to 28% lower for conifers grown in altered soil whereas dry mass of Artemisia tridentata and Bromus tectorum L. was reduced by over 90%. Results from a nutrient amendment experiment indicated that low phosphorus was the dominant limitation in altered soil, and phosphorus-deficiency affected growth primarily by limiting leaf area development rather than direct inhibition of photosynthesis. The proportionately greater reduction of biomass for Artemisia and Bromus grown in altered soil supports our hypothesis that Great Basin vegetation is excluded from altered soil by intolerance to nutrient deficiency. The Sierran conifers growing on this rock type are therefore free of competition for water with Great Basin vegetation and are able to persist in an exceptionally dry climate.