A Biological Restoration Model for Contaminated Coastal Marshes and Islands Using the Life Cycle of Acheta domesticus to Establish Environmental Sustainability

摘要

Insects such as Acheta domesticus account for over half of marsh fish and migratory bird diet. Therefore, insectsare very important to marsh and island ecosy stems and are susceptible to oilcontamination, but little research has been done to study the effects of oilspills on cricket populations. The purpose of this experiment was to determinethe effects of an oil spill event on Achetadomesticus mortality and hatch rate to establish environmentalsustainability. The treatment groups included 0% oil contamination, 5% oilcontamination and 10% oil contamination. The scientist counted the number ofdeaths in two-week, four-week, and six-week-oldcrickets after oil contamination. In addition, the scientist counted the numberof hatchlings among treated cricket eggs. Error bar lines in the resultssection supported the scientist’s hypothesis that the crickets would beaffected by oil contamination. In fact, over 90% of the 10% oil treatment groupdied and over 80% of the 5% oil treatment group died after five days of oilcontamination in the six-week-old experiment. The scientist used a GasChromatography Mass Spectrometer to determine if benzene, toluene,ethylbenzene, or xylene (total) were present in the sediment samples. BTEXexposure is suspected to possibly cause insect mortality. These volatileorganic compounds were present in the samples and were found in higherquantities in samples with higher concentrations of oil. The highest quantityof volatile organic compounds present was xylene. After studying the populationdynamics of the tested Acheta domesticus, the scientist found that the two-week and four-week-old crickets’survivability could fit a linear model while the six-week-old crickets fit anexponential model. The scientist used these models to observe how long it tookeach treatment group to approach zero, and the oiled groups grew closer to apopulation of zero significantly faster. For example, it took abouttwenty-seven days for the 10% treatment group’s population to approach zerowhereas the control, 0% treatment group, took about seven days in the two-week-old cricketexperiment. Overall, the six-week-old crickets had the highest mortality, andthe cricket egg experiment resulted in extremely low hatch rate. Specifically,the highest number of crickets that hatched in an oiled replication either 5%or 10% oil was eight out of the five thousand eggs laid. Since the adultcrickets are the most physically able to reproduce and the cricket eggs had lowhatch rates, the cricket population would significantly decrease after an oilspill with 5% or more soil contamination. However, if the plant matter thatcrickets consume is still present in their environment, they may be able torecover.