Human influence on aquatic environments is not a novel issue, but the extent of anthropogenic factors negatively affecting aquatic ecosystems have grown in intensity and occurrence. Humans influence aquatic environments both directly and indirectly because activities which take place on land can also disrupt the harmony of aquatic environments.
Human influences on aquatic environments cause instability in freshwater and marine ecosystems and lead to the decline of aquatic plant and animal species. Activities such as commercial fishing and pollution directly impact aquatic environments. In the past century advances in fishing technology have made the over exploitation of fish stocks a major issue. For example, on continental shelf areas, it is thought that fish stocks have been fully exploited1.
Pollution is another major stressor on aquatic ecosystems. The dumping of garbage into oceans has long been a problem. Commonly today, toxins from industrial plants or accidental spills have been polluting surrounding waters. This has negative consequences, killing organisms, destroying food chains and diminishing water quality. Furthermore, some effects from toxic compounds may not be noticed right away and will instead bioaccumulate up food webs. This negatively impacts top predators and humans in many cases.
In addition, activities on land are contributing to environmental changes which are in turn inducing negative impacts on aquatic ecosystems. Some examples are the effects of climate change and eutrophication. Eutrophication is the result of fertilizer runoff entering water systems and inturn, increasing the levels of dissolved nitrogen and phosphorous. Climate change is resulting in the rising of sea levels, melting of ice sheets and elevating water temperatures.
Unfortunately, there are numerous other anthropogenic activities, such as acidification and the destruction of coastal habitats, which are threatening aquatic ecosystems. The problems facing aquatic ecosystems in the twenty-first century have largely been created by the increasing sophistication of civilization and thus, humans must find the tools to solve them.
1. Science Learning Hub. (2014). Human Impacts on Marine Environments. Retrieved from http://www.sciencelearn.org.nz/Contexts/Life-in-the-Sea/Science-Ideas-and-Concepts/Human-impacts-on-marine-environments
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