Productivity is highest in what type of ocean

This means the warm water in effect gets stuck above the cold water where all the nutrients are. In temperate zones, this only happens in the summer.

In the fall as the surface waters cool off, they begin to mix with the waters beneath them, and this mixing, with the help of winter storms, stirs up nutrients. So the ocean is more productive in temperate zones. This also explains why the tropics have that pretty clear blue water. This pattern is illustrated below:. So in temperate zones I just said that in winter the water mixes easily and so nutrients are available and so productivity is high, right?

Well, no. Come spring though, the nutrients are still there, the sun increases and the algae goes crazy. This is called the spring bloom. This ends the bloom by summer. We said nutrients come from land, and so coastal water is the most productive. This has a down side. Coastal pollution is a big problem.

All the pollutants we spew over the land eventually wash into the water one way or another, or we simply directly dump into the water. Unfortunately, humans like to live along the coast, and more and more of us are doing that. And even if you are on a sewer line so your sewage is treated before it winds up in the water, and you are conscientious about not dumping toxins down the drain, you are part of the problem. Your car emits all sorts of nasty things. You probably get your electricity from a steam plant fired by coal which puts mercury in coastal water.

First of all, the nutrients, especially nitrogen and phophorous, are limiting. This means that algae would grow more if there were more of these available. Well, guess what? Nitrogen is the primary nutrient in sewage, be it yours or a pig farms. In addition, farms and golf courses use fertilizers on their grounds and a lot of this tends to run off and end up in the water.

Phosphorous is found in many of our cleaning products which all end up down the drain and in the water too. And so coastal algae often has a regular smorgasbord of nutrients available. In response to this, it blooms. Well yes, to a point. But very quickly there is more food than the fish can eat. In fact there is so much algae that it actually starts blocking its own light source and so it starts dying. Not too much eats dead algae. Community guidance for developing this website was to provide a single productivity product as a Standard product.

The VGPM is a "chlorophyll-based" model that estimate net primary production from chlorophyll using a temperature-dependent description of chlorophyll-specific photosynthetic efficiency. For the VGPM, net primary production is a function of chlorophyll, available light, and the photosynthetic efficiency.

Monthly global ocean production for November was 3. As stated above, Custom Products provides ocean productivity estimates for different satellite data sets and alternative productivity algorithms. In that paper, Eppley evaluated changes in phytoplankton growth rates over a range of temperatures for a wide variety of species.

What he noticed was that the maximum specific growth rate achieved at a given temperature was higher at high temperatures than at low temperatures. He then fit an exponential curve to this data that capped all the growth rates across the measured temperature range.

While Eppley's analysis has no direct relationship to the description of average photosynthetic efficiencies, its application in ocean productivity models is commonplace. While this may seem rather unfounded, there actually is a good reason why an exponential function may give reasonable estimates of photosynthetic efficiencies -- that reason is photoacclimation.

Photoacclimation is a process found in all ocean and land plants that allow them to adjust to changes in light level. When plants are grown at low light, they have a lot of pigment to help them gather as much light energy as possible. If you transfer the same plants to high light, they quickly reduce the amount of pigmentation to prevent damage from absorbing too much light.

If you were to measure the photosynthetic efficiency per unit of pigment under low and high light conditions, you would find that the high light treatment had the highest efficiency. This helps increase productivity to coral reefs. The shows the coast of Australia, and the Great Barrier Reef shows up as high productivity specks to the east.

This image of the equatorial region around the Galapagos Islands shows the possible effects of natural iron that is derived from these volcanic islands. The Island Mass effect can also be seen around Tasmania. The polar westerlies blow around the Southern Ocean, and drive a eastward current. As this current approaches Tasmania, the upwelling of nutrient rich water fuels primary productivity. See if you can explain all the patterns of productivity shown here. The deep blue path of water running past Cape Hatteras, then offshore is the Gulf Stream.

Why is the Gulf Stream low in productivity? The famous fishing grounds called Georges Bank is the red color east of Cape Cod. This shows the effect of currents dragging deep waters over shallow bottom bank. The post has no comments. Leave a Reply Cancel reply Your email address will not be published. For more information, visit our Privacy Policy page. Next article. Drysuits — Buying Your First Drysuit.

Legal Info divessi. Filter posts by language:. We use cookies to ensure that we give you the best experience on our website. If you continue to use this site we will assume that you are happy with it.