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"The eleven chapters cover many aspects of the physics, geochemistry and biology of the lake, with a particular focus on the unique physical and geochemical features of the water column and on the ecological functioning of the surface waters. The impacts of the introduced fish species and the potential impacts of methane exploitation are also summarized. This multi-disciplinary book may also be used as an introduction to the limnology and biogeochemistry of large tropical lakes, as it covers various aspects of the physics, geochemistry, biology and ecology of the African Great Rift lakes.​"

"A natural phenomenon called as tubo belerang had occurred repeatedly in Lake Maninjau where the sulfide odorous water was apparent causing massive fish kill. Sulfur biogeochemistry in sulfur rich lakes can be critical when inputs of organic matter are high as in Lake Maninjau which has been exploited by floating cage fishery. The objective of the research is to study the biogeochemistry of sulfur in Lake Maninjau and to determine what factors might initiate the natural phenomenon occurrence. The Oxycontin layer had Sheffield from the depth of 20-40 m in 2006 to the depth of 10-20 m in 2008. The dynamics of bio geochemistry of sulfur in Lake Maninjau could be perceived from Sulfide profiles where increasing Sulfide concentrations detected annually. Higher Sulfide concentrations produced indicating more sulfate was reduced in the hypothalami layer. Sulfide concentration reached at level of 5 mg/L in the pore water of sediment. The toxic hydrogen sulfide concentrations were 10 - 120 ug/L. Sulfate concentrations ranged from 4 to 16 mg/L. Based on the pH values, the sulfur species H2S and HS were present in the lake water. Most of sulfur in Lake Maninjau were deposited in the sediment as iron Sulfide solids. The accumulation of organic matter in the hypothalami in the deepest part of the lake and Sheffield Oxycontin layer in four year observation periods indicated that the effect of floating cage fishery on the lake conditions was apparently atrocious. Increased in concentration of organic matter could play an important role on the dynamic of bio geochemistry of sulfur in Lake Maninjau and could be one of the major causes that might trigger the tubo belerang occurrence."

"In this study, a three-dimensional (3D) hydrodynamic model was developed to investigate the Watercirculation characteristics of a shallow tropical lake environment (Laguna Lake, Philippines) undervarying wind stress, watershed river discharge, and sea interaction (Manila Bay, Philippines) toelucidate hydrodynamic implications to eutrophic vulnerability. The analyses were based on fieldobservations and numerical simulations covering longterm periods (dry and wet season) andintensive field measurements. The results demonstrated different circulation pattems and verticalcurrent regimes in time and space that accentuated a thermally stratified lake environment in spiteof a shallow water depth (2.5 meter average). In the wet season, current movement is generallytoward Pasig River, the lake’s only outlet, with embayment water mass moving in the clockwisedirection. The dry season lake flow pattern was characterized by counter-clockwise gyrecirculations, Pasig River backflow, and salinity intrusion. Wind forces showed strong influence onlake hydrodynamics due to the complex surrounding topography, steep land-ake thermaldifference, regular passage of tropical storms and typhoons, and shifts in the monsoon winddirection. The resulting mixed layer hydrodynamics revealed important implications to theplanktonic movement, nutrient recycling, and primary production of the lake. Long termcontinuous observations and numerical analyses also demonstrated the intrusion of seawater toLaguna Lake that potentially adds to its eutrophic vulnerability with the associated entry of nutrientand microorganism-rich polluted waters from Metro Manila."

"The problem of eutrophication and its factors become one of the major water quality problems. In the USA the problem over one half of the surface water supplies are due to excessive growth of aquatic plants. Other consequences are the decline in suitability of the water for industrial and water supply, and a general loss of attractiveness from the recreational point of view. Those problems appear due to the development of weeds and scummy blooms of blue green algae anabaena. Many of these algae produce unpleasant odor and tastes. The worst thing in eutrophication is that the change seems to be irreversible. Sudden appearances of bloom in lake are generally human activities responsibility."