Comparisons of Chlorophyll Content and Leaf Structure in Arctic and Alpine Grasses

Tieszen, Larry

Grasses under natural conditions from arctic and alpine tundras were compared with respect to pigment content, leaf density-thickness, and width. General differences between arctic and alpine grasses were not large. The higher fresh weight to dry weight ratios in arctic plants were reflected in slightly higher density-thickness values on a fresh weight basis and lower values when based on dry weight. In both tundras, grasses with low density-thickness values were characteristically found in very wet and/or protected habitats, whereas those with higher values occupied drier and more open sites. The correlation between density-thickness and leaf thickness was high, especially on a fresh weight basis. Leaf width appeared greater in the Arctic. Chlorophyll contents differed most markedly on a dry weight basis with arctic grasses possessing the highest concentrations. When based on fresh weight and area, differences were not readily apparent. Chlorophyll on an area basis was strongly correlated with fresh weight density-thickness. The ratios of chlorophyll a to b were low in plants from the Arctic. Within either region the ranges for pigment contents and other leaf measurements were large, but the above correlations were found both between species and within species.

Comparisons of Chlorophyll Content and Leaf Structure in Arctic and Alpine Grasses

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