Triharmony/Trilemma of Nutrients Assets in tropical peatland

Abstract

in the Maritime Continent of Southeast Asia, the region between the Indian and Pacific Oceans, including Indonesia, Borneo, New Guinea, the Philippines, and the Malay Peninsula (1,2). Peatlands are defined by three main characteristics: carbon-rich peat soils, high water levels, and low soil and water nutrient contents. Their lownutrient environment arises through a number of factors. Peat is composed of carbon-rich fibres, mainly lignin, which are nutrient poor, with nutrient desorption outweighing adsorption. The low pH of the soil (<4) exacerbates this low cation (positive ion) absorption capacity; even nutrients in fertilizers are applied, resulting in limited exchange efficacy. In addition, peatland geomorphology controls the source of water. Peatland regions form peatland domes, areas of relatively higher topography (approx 10m elevation in the centre, dropping to river level along a radius of approx 10km) created by thick layers of peat soils. As natural water courses (rivers) flow around these structures, they do not offer a water source for the peat soils within the dome. Therefore, precipitation, which is naturally nutrient poor, forms the primary water source. The relatively acidic pH of precipitation (~5.6) also contributes to nutrient leaching (1). An additional confounding factor is oxygen deficiency due to extremely low oxygen solubilisation into the water due to physical traits, resulting in reduced nutrients absorption by plants [Figures 1 and 2].