Aquatic Dead Zones

This is not the first story I have posted where negative environmental impacts were contributed to runoff. One threat facing coral reefs is pollution from rivers and other land runoff. Poor forestry practices in some countries has resulted in silt being washed into rivers then into the ocean and onto coral reefs. The coral dies as the silt blocked the sunlight preventing photosynthesis to occur. Silt is not the only killer in runoff.

Better land management and eliminating or better controlling the use of dangerous chemicals would be one step toward eliminating situations like this. Fertilizers and sewage are big on the list of contaminates that need to be addressed.

There are steps we can all take to minimize our contribution to the runoff issue. The ways to help are too extensive for me to list here though you can watch for a future post that goes into greater depth. Here are a couple ways that come to mind:

- Use a car wash that recycles their water instead of washing your car at home (at our homes the soap will go into the storm drain and out to the ocean).

- Opt for an organic lawn or landscape. Fertilizers and Pesticides will wash away into storm drains.

- Use low-phosphate or phosphate-free detergents.

- Use alternative cleaning solutions around the home. For much of my cleaning I use a vinegar water solution (some essential oil can be added for fragrance).

Again there are other ways we can do our part and these are just a few that come to mind simply because they are part of my routine.


Full downloadable image here

The size and number of marine dead zones—areas where the deep water is so low in dissolved oxygen that sea creatures can’t survive—have grown explosively in the past half-century. Red circles on this map show the location and size of many of our planet’s dead zones. Black dots show where dead zones have been observed, but their size is unknown.

It’s no coincidence that dead zones occur downriver of places where human population density is high (darkest brown). Some of the fertilizer we apply to crops is washed into streams and rivers. Fertilizer-laden runoff triggers explosive planktonic algae growth in coastal areas. The algae die and rain down into deep waters, where their remains are like fertilizer for microbes. The microbes decompose the organic matter, using up the oxygen. Mass killing of fish and other sea life often results.

Satellites can observe changes in the way the ocean surface reflects and absorbs sunlight when the water holds a lot of particles of organic matter. Darker blues in this image show higher concentrations of particulate organic matter, an indication of the overly fertile waters that can culminate in dead zones.

Naturally occurring low-oxygen zones are regular features in some parts of the ocean. These coastal upwelling areas, which include the Bay of Bengal and the Atlantic west of southern Africa, are not the same as dead zones because their bottom-dwelling marine life is adapted to the recurring low-oxygen conditions. However, these zones may grow larger with the additional nutrient inputs from agricultural runoff.

WOW you should overlap that chart with the one that shows all the oil spills!!

WOW!!

Good find !!!

I think the Gulf was one of the first hit really hard from the switch to corn for fuel, so alcohol gas and dead zones too, my but we are filthy creatures

Originally Posted by high tide

we are filthy creatures

Humans and seahorses right Steve?

mmm Ive never met a mean seahorse lol

Originally Posted by high tide

mmm Ive never met a mean seahorse lol

Mean no...from what I hear they are "filthy" (dirty) though. Guess I will find out soon enough.

I don't believe the ponies themselves are filthy animals, they just encourage algae growth with their good nature d ways

good reminder of how what we do truly does make a difference ... another great post jason!