Evidence of sea water Boron in the lower layers of tropical woody peat

Abstract

For the assessment and proper use of tropical peatlands, chemical problems such as nutrient deficiencies and toxicities should be solved. The concentration of the essential trace element boron, which is in tropical peat soil, is very low (about 1⁄10 of the cultivated mineral soil in Japan), however, in layers below 40 cm depth of inland peat B is abundantly fixed. The effect of sea water was estimated, because the water soluble Na content in these layers was high and the water soluble Mg/Ca ratio in them was as high as that of sea water. Therefore, in these layers the B appears to be fixing the high levels of B in the sea water. Various gaps have developed in the lower layer of the inland peat indicating that the sea water can infiltrate with the pressure of the flood-tide.