The physical effects of simulated acid rain on the mortality and embryonic development of toad (Bufo sp.).

          This study generally aimed to determine the physical effects of simulated acid rain using sulfuric acid alone on the mortality and embryonic development of toad (Bufo sp.) from July 29, 2016 to August 24, 2016. This study sought to answer the following problems: the percentage mortality of toad embryo exposed to simulated acid rain using sulfuric acid alone of 4.9pH, 5.1pH, 5.3pH, and 5.5pH; and the control group, groundwater, with a 7.2pH, the mean body size in millimeters squared exposed to simulated acid rain using sulfuric acid alone of 4.9pH, 5.1pH, 5.3pH, and 5.5pH; and the control group, groundwater, with a 7.2pH, and the significant difference in the mean body size in millimeters squared exposed to simulated acid rain using sulfuric acid alone of 4.9pH, 5.1pH, 5.3pH, and 5.5pH; and the control group, groundwater, with a 7.2pH. This study was an experimental type utilizing a completely randomized design (CRD). The research was conducted at the laboratory room of the Biology Department of Cebu Doctors' University in Mandaue City, Cebu. The study utilized a sample of 10 per group for a total of 50 embryos. These amphibians were collected on July 29, 2016 from a pond in Guba, Talamban, Cebu. Each experimental group was placed in a 12x6x8.5" glass aquaria that was filled with one liter of simulated acid rain using sulfuric acid alone with the specific pH levels. The control group was placed in another 12x6x8.5" glass aquarium which was filled with one liter of groundwater taken from Barangay Lower Natimao-an, Carmen, Cebu. Throughout the span of the experiment, the number of deaths were recorded and once the subject reached Gosner stage 46, photos of the ventral side of the body were obtained using Nikon Coolpix P520 digital single-lens reflex (DSLR) camera to determine its size. Fractal analysis was utilized to gauge the measure of varieties expressed in the abnormality of the growth of appendages of toads in terms of size. The average of five trials of fractal analysis done on each subject was used as the data in the computation for the mean ±SD.

          No deaths (0%) occurred in the control group, one death (10%) in 4.9pH simulated acid rain treatment, and two deaths (20%) each for 5.1pH, 5.3pH, and 5.5pH simulated acid rain treatment. There was no significant difference in the mean body size (mm squared) across the experimental and control groups using One-Way Analysis of Variance (ANOVA). No significant test in the percentage mortality was done since Chi-square test assumption was not satisfied.

          Based on the findings, it was concluded that exposure of Bufo sp. Embryo to an acidic environment caused mortality and did not have a significant effect on their development in terms of its whole body size. We recommend the teachers to continue educating about food web or food chain that may affect ecosystem imbalance and students to continue understanding on the importance of amphibians in maintaining the ecosystem balance.