Ridge-Reef-Responsibility II

Ridge-Reef-Responsibility II

In lieu of the more ecological conservationism themes of the previous lab trips, it seems that I can still continue with this ridge-to-reef preservation narrative. As rain falls, it brings whatever it catches down the hill into the stream with it. Whether it will be silt, nutrient-fixing bacteria, or biohazardous pathogens; if it gets caught in the stream, there is little to nothing that will stop it from reaching the water lens, sea level, and ultimately, the human population. In many tropical island nations, and many places that receive large amounts of rainfall, the freshwater lens and the surrounding reef downstream from affected streams are periodically threatened by contamination.

The freshwater aquifer contained in the porous limestone geology of places like the northern half of Guam are susceptible to nasty pathogens found in animal feces, the chemicals and heavy metals of careless, illegal dumps, and other runoff from roads and automobiles. While quite a bit of the runoff is in fact filtered out before actually reaching the freshwater lens, the contaminants still leave trace elements that could be potentially dangerous for the community. A tried and true solution to keep the scary stuff from reaching the water table has been to situate water purifying plants in and near streams and rivers. Plants like reeds and other large grasses are suited to inland water purification, but since the freshwater always seeps down into the ground to get to the water lens, action needs to be taken before the water even gets below ground. By properly regulating where livestock can be housed, enforcing litter laws on biohazardous waste, and designing effective culverts and other water redirection systems, the more policy-driven changes can be found therein.

Otherwise, for water that does find itself on its way to the ocean and nowhere near the freshwater aquifer, ecologists would need to watch for the same contaminants and be wary of it affecting the reefs. While reeds and other large grasses are better suited to wetland habitats, estuaries are home to mangroves and their brackish water environments. Like the limestone filtering out contaminants before it reaches the freshwater lens, the estuaries and the marshlands with other large reeds and the mangroves help to effectively treat the water and purify it before it reaches the lagoon. By protecting these marshlands and estuary regions and by recreating the “filter regions” on rivers and streams susceptible to upstream contamination, the community can protect their reefs from potentially dangerous runoff.

In order to test for the facility of the water purifying plants and other mitigation solutions, there would need to be a lot more science and laboratory testing involved. Researchers involved in the mitigation projects would test the waters drawn from local aquifers and beaches monthly or after heavy rainfall for any biotic or abiotic factors that would make the water unfit for consumption, recreation, and/or fishing. Analyzing for any levels of contaminants or other trace elements can give the scientific community involved a better understanding of what is happening upstream. Any level of any contaminants and/or pathogens would be a sign for the community to be on alert of their individual actions on the environment and of the general human actions on the environment. By maintaining and protecting the marshlands and estuaries that treat the water that we use, we can preserve and look for a better future for ourselves and our progeny. If by human action the reef and the water is threatened, it is by human action that change needs to happen.

BI100L-02 | R. Kim
October 7, 2017