The freshwater lakes of Papua New Guinea: an inventory and limnological review

Abstract

ABSTRACTA survey of the 1:100,000 topographic maps of Papua New Guinea revealed that there are about 5383 freshwater lakes in the country. They range in size up to 647 km2 but the majority are less than 10 ha. They are found at all altitudes to over 4000 m but most are situated below 40 m in the floodplains of the Fly, Sepik and Aramia rivers. The majority of lakes are undoubtedly shallow but depths range up to 360 m. The lakes were formed in at least 20 different ways but the majority by fluviatile action. The few data on chemical and physical conditions suggest that most lakes are chemically poor with low light penetration and low pH values. With the possible exception of the macrophytes the fauna and flora of the lakes are virtually unstudied, particuarly from a quantitative aspect. Most lakes are probably polymictic.