Oceans
Ocean water quality: tide pools, estuaries and the near shore
The ocean covers about 71 per cent of the Earth's surface and does most of the planet's thermal work. It has absorbed the large majority of the excess heat trapped by greenhouse gases, and roughly a quarter to a third of the carbon dioxide emitted by human activity. That dissolved CO2 forms carbonic acid, and average surface ocean pH has fallen by about 0.1 units since the industrial revolution — because pH is logarithmic, that is an increase in acidity of roughly 30 per cent. It makes calcium carbonate harder to build, which is a direct problem for corals, oysters, clams and the small shelled plankton at the base of the food web.
Close to shore, the dominant pollution problem in developed coastlines is not an oil spill but everyday urban runoff. Storm drains discharge untreated, so oil from roads, garden fertiliser, pet waste, cigarette butts and litter arrive in the surf zone essentially as they left the street. That is why beach bacteria counts spike after rainfall and why health agencies advise staying out of the water for up to 72 hours afterwards.
Estuaries and tide pools are where this is easiest to see. An estuary — where fresh river water meets salt — is among the most productive habitat types on Earth and acts as a nursery for a large share of commercially fished species. Tide pools in the rocky intertidal are a genuine extreme environment, exposing anemones, sea stars, urchins and limpets to twice-daily swings in temperature, salinity and exposure. Both are shallow, enclosed and slow to flush, which makes them unusually sensitive to what arrives from land.
Facts worth keeping straight
- Coral reefs occupy well under one per cent of the ocean floor but support roughly a quarter of all marine species.
- In the region of eight million tonnes of plastic enter the ocean every year, much of it from land-based sources rather than ships.
- Most marine plastic breaks into microplastics rather than disappearing; it is fragmented, not degraded.
- A storm drain is not a sewer. Nothing entering one is treated before it reaches the water.
- In a tide pool, look and do not lift — sea stars and anemones are attached, and prising one loose usually kills it.
Useful and Interesting Links
Each of the links below opens in a new browser window, so The-Environment.net stays open behind it.
Advocates for wild, healthy, protected, and pollution free oceans with flourishing ecosystems and abundant marine wildlife.
Organization dedicated to making Santa Monica Bay and Southern California coastal waters safe and healthy again for people and marine life.
is a national organization dedicated to improving the quality of our nation's oceans, rivers, streams and waterways to ensure that our natural resources are healthy, safe, and clean.
A site dedicated to saving our planet’s seas and all marine life through research, education and conservation. Based in Maui, Hawaii.
A Smithsonian institution travelling exhibition that celebrates the diversity of the ocean’s and examines the environmental issues they now face.
Dedicated to the conservation of the world’s ocean and seas.
and wastewater treatment Site dedicated to saving the coral reefs around the world. Make sure and check out the wastewater garden section for any wastewater discharge needs.
More on The-Environment.net
- Local Topics — beach monitoring, closures and wetland restoration near you.
- Wild Life — the marine species these pressures fall on.
- Recycling — keeping plastic out of the watershed in the first place.