Aluminium in Lake Cuicocha, Ecuador, an Andean Crater Lake: Filterable, Gelatinous and Microcrystal Al Occurrence

作者：Gunkel G^*; Beulker C; Grupe B; Gernet U; Viteri F

来源：Aquatic Geochemistry, 2011, 17(2): 109-127.

DOI：10.1007/s10498-010-9114-z

• Aluminium
• Al polymerization
• Gelatinous Al
• Lake water
• Mircocrystals
• Water quality

In Lake Cuicocha watershed, a young caldera lake, soils consist of volcanic deposits with a high SiO(2) and Al(2)O(3) content; these andisols are in an early stage of development; and in drainage water from the watershed, aluminium concentrations reach 15.0 mu mol L(-1). Total aluminium concentrations in Lake Cuicocha water raises up to 7.2 mu mol L(-1), with nearly 70% occurring as filterable Al at neutral to weak alkaline conditions. Al polymerization to gelatinous aggregates of a few hundred micrometres in diameter as well as the occurrence of Al microcrystals like gibbsite as an ageing product of gelatinous Al polymers was noted in the lake water. The gelatinous Al leads to the formation of larger aggregates resulting in flocs of bacteria, algae, microorganisms and detritus.