Date of Publication
8-2026
Document Type
Bachelor's Thesis
Degree Name
Bachelor of Science in Biology
Subject Categories
Biology
College
College of Science
Department/Unit
Biology
Thesis Advisor
Emelina H. Mandia
Erica Silk P. Dela Paz
Defense Panel Chair
Christian Jordan O. Dela Rosa
Defense Panel Member
John Paul S. Domingo
Sarah Grace S. Zamudio
Abstract (English)
The study investigated seasonal variations in physicochemical water properties and phytoplankton richness in the Carmona River, Laguna, comparing the surface and bottom waters across the habagat (wet) and amihan (dry) seasons. The habagat season was characterized by cooler, highly alkaline, and well-aerated waters with lower conductivity and total dissolved solids, while the amihan season exhibited warmer temperatures, lower pH and dissolved oxygen, and higher conductivity and total dissolved solids. A multiparameter meter was used to measure pH, temperature, dissolved oxygen, conductivity, total dissolved solids, while nutrient concentrations (nitrate and phosphate) were measured through spectrophotometry. Phytoplankton richness was determined based on microscopic analysis of Lugol's-fixed and BG-11 enriched samples. The Jaccard Similarity Index was used to assess the similarity of phytoplankton richness across seasons and surface-bottom waters. Menhinick’s Index was used to account for phytoplankton genus richness across water depths during the two seasons. Statistical analysis via two-sample t-tests (p < 0.05) confirmed significant seasonal differences in water quality and nutrient levels, driven by monsoon-induced hydrological changes. Spearman’s Correlation indicated that pH and phytoplankton richness had a positive relationship (ρ = 0.630, p = 0.03). Notably, there were no significant differences found between surface and bottom water properties, indicating uniform vertical mixing in this lotic system. A total of 31 genera under six phyla (Bacillariophyta, Charophyta, Chlorophyta, Cyanobacteria, Dinoflagellata, and Euglenophyta) were documented, with Bacillariophyta as the dominant group. Phytoplankton richness was higher during the habagat season, but the presence of taxa in both seasons demonstrated their resilience to changing environmental conditions. The findings of this study established critical baseline data for the Carmona River, determining the role of phytoplankton as sensitive bioindicators of the river's ecological rhythm.
Abstract Format
html
Abstract (Filipino)
Sinuri ng pag-aaral ang mga pagbabago ayon sa panahon sa mga katangiang pisikokemikal ng tubig at kasaganaan ng phytoplankton sa Ilog ng Carmona sa Laguna, sa pamamagitan ng paghahambing sa tubig sa ibabaw at sa ilalim nito sa panahon ng habagat at amihan. Ang panahon ng habagat ay kinatampukan ng mas malamig, lubos na alkaline, at may sapat na hangin ng tubig na may mas mababang conductivity at total dissolved solids; samantala, ang panahon ng amihan ay nagpakita ng mas mataas na temperature, mas mababang pH at dissolved oxygen, at mas mataas na conductivity at total dissolved solids. Ginamit ang isang multiparameter meter upang sukatin ang pH, temperatura, dissolved oxygen, conductivity, at total dissolved solids, habang ang konsentrasyon ng mga sustansya (nitrate at phosphate) ay sinukat gamit ang spectrophotometry. Tinukoy ang kasaganaan ng phytoplankton batay sa pagsusuri gamit ang mikroskopyo sa mga sample na inihanda gamit ang Lugol’s solution at enrichment ng BG-11 medium. Ginamit ang Jaccard Similarity Index upang suriin ang pagkakatulad ng kasaganaan ng phytoplankton sa iba’t ibang panahon at sa pagitan ng tubig sa ibabaw at ilalim. Ang Menhinick’s Index naman ay ginamit upang suriin ang kasaganaan ng phytoplankton genera sa magkaibang lalim ng tubig sa dalawang panahon. Kinumpirma ng pagsusuring estadistikal gamit ang two sample t-tests (p < 0.05) ang mga makabuluhang pagkakaiba ayon sa panahon sa kalidad ng tubig at antas ng sustansya, na dulot ng mga pagbabagong hidrolohikal na dala ng monsoon. Ipinakita ng Spearman’s Correlation na may direk na linyar na ugnayan ang pH at kasaganaan ng phytoplankton (r = 0.630, p = 0.03). Kapansin-pansin na walang nakitang makabuluhang pagkakaiba sa mga katangian ng tubig sa ibabaw at ilalim, na nagpapahiwatig ng pantay na paghahalo (uniform vertical mixing) sa sistemang ito ng dumadaloy na tubig (lotic system). Naitala ang kabuuang 31 genera sa ilalim ng anim na phyla (Bacillariophyta, Charophyta, Chlorophyta, Cyanobacteria, Dinoflagellata, at Euglenophyta), kung saan ang Bacillariophyta ang naging dominanteng grupo. Mas mataas ang kasaganaan ng phytoplankton sa panahon ng habagat, ngunit ang presensya ng mga taxa sa parehong panahon ay nagpakita ng kanilang kakayahang makayanan ang nagbabagong kondisyon ng kapaligiran. Ang mga resulta ng mga pag-aaral na ito ay nagbigay ng mahahalagang batayang datos para sa Ilog Carmona, na tumutukoy sa papel ng phytoplankton bilang mga sensitibong bioindicator ng ekolohikal na ritmo ng ilog.
Abstract Format
html
Language
English
Format
Electronic
Keywords
Phytoplankton--Philippines; Rivers--Philippines--Laguna
Recommended Citation
Zabala, M. D., & Agustin, M. G. (2026). Rhythms of the river: Seasonal surface and bottom water properties and phytoplankton diversity in the Carmona River, Laguna, Philippines. Retrieved from https://animorepository.dlsu.edu.ph/etdb_bio/227
Upload Full Text
wf_yes
Embargo Period
8-28-2027
