Nuclear microprobe studies of elemental distribution in the seagrass Thalassodendron ciliatum

Elemental levels and distributions in various organs (leaves; upright stems, rhizomes and soots) of the seagrass Thalassodendron ciliatum were determined using the NAC nuclear microprobe. Elemental distributions were obtained using the true elemental imaging system Dynamic Analysis (DA). CI was the most abundant element present in the organs, occurring in all tissues, but present in relatively low concentrations in epidermal cells of leaves and roots. Na, K, S and Mg were also abundant and occurred in all organ tissues. Ca concentration was highest in the leaves, especially in the epidermis. Low concentrations of P were found and its tissue distribution was limited. Although Fe, Cu, Zn, Mn, Br, Ti and Si were present in relatively small amounts, enrichment of the epidermis with Fe, Ti and Si in all organs, was observed. Fe concentration was the highest in rhizomes while Si concentration was highest in upright stems. The significance of these elemental distribution patterns and the value of the nuclear microprobe in elemental analysis of seagrasses are discussed. (C) 1999 Elsevier Science B.V. All rights reserved.