Journal of Geoscience and Environment Protection, 2021, 9, 53-67 https://www.scirp.org/journal/gep ISSN Online: 2327-4344 ISSN Print: 2327-4336 DOI: 10.4236/gep.2021.91004 Jan. 22, 2021 53 Journal of Geoscience and Environment Protection Characteristic Relationships between Phosphorous Accrual, Ecosystem Aspects and Water Level Fluctuations in Tropical Lakes: Naivasha Ramsar Site, Kenya Beatrice N. Obegi 1,2* , George M. Ogendi 3,4 , Reuben Omondi 2 , Boston J. Siriba 2 , George N. Morara 1,2 , Nehemiah M. Rindoria 5 , Paul Orina 6 1 Kenya Marine and Fisheries Research Institute, Naivasha, Kenya 2 Department of Aquatic and Fishery Sciences, Kisii University, Kisii, Kenya 3 Department of Environmental Science, Egerton University, Kenya 4 Dryland Research Training & Ecotourism Centre, Chemeron, Egerton University, Kenya 5 Department of Biological Sciences, Kisii University, Kisii, Kenya 6 Kenya Marine and Fisheries Research Institute, Kegati, Kenya Abstract Hydrological dynamics affect water levels and thus affecting ecosystem structure and functions. Lake levels in tropical ecosystems affect phosphorous input through runoff from adjacent watersheds. The resultant biological community, water and sediment quality of the lakes due to water level changes is a reflection of the geology of the area and the anthropogenic activities in the watershed. The study conducted between January 2018 and December 2019 was to explore relationships between the phosphorous input and Water Level Fluctuations (WLF) recorded by Water Resource Authority (WRA). Lake water samples were analyzed in the laboratory for phosphorous using molybdenum blue-ascorbic method and recorded using spectrophotometer. Chlorophyll- a was determined by extracting a filtered sample with 15 ml acetone and incubating overnight and thereafter read using a double beam spectrophotometer. Total Suspended Solids (TSS) was determined by filtering 200 ml of a water sample and dried overnight at 105˚C. The lowest and high- est phosphorous concentrations recorded were 0.2 mg/l and 0.42 mg/l at NST7 and NST2, respectively. Measurements of Chlorophyll- a were 0.32 mg/l and 0.42 mg/l at NST9 and NST2, respectively. Secchi transparency measurements were 32.9 cm at NST3 and 84 cm at NST1. The highest and lowest TSS concentrations were 0.14 mg/l and 0.13 mg/l at NTS1 and NST8, respectively. The hydrodynamic regime in most tropical lakes plays a signifi- How to cite this paper: Obegi, B. N., Ogendi, G. M., Omondi, R., Siriba, B. J., Morara, G. N., Rindoria, N. M., & Orina, P. (2021). Characteristic Relationships between Phosphorous Accrual, Ecosystem Aspects and Water Level Fluctuations in Tropical Lakes: Naivasha Ramsar Site, Kenya. Jour- nal of Geoscience and Environment Pro- tection, 9, 53-67. https://doi.org/10.4236/gep.2021.91004 Received: December 11, 2020 Accepted: January 19, 2021 Published: January 22, 2021 Copyright © 2021 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access