The smallest planktonic organisms, less than 20 [m in diameter, are termed nanoplankton. These (and many microplanktonts) escape through fine-mesh plankton nets but may be collected by centrifuging, membrane filtration, or sedimentation (see page 67). This diverse group of minute organisms includes the smallest diatoms and dinoflagellates, coccoliths (see below) various other small flagellates known collectively as microflagellates, and also fungi and some bacteria.

It is only in fairly recent years that the nanoplankton has been much studied, but it now appears that the quantity of living material in the water in this form sometimes exceeds that present as diatoms and dinoflagellates. The nanoplankton is now thought to make a major contribution to the primary production of organic food in the sea, and is specially important as the chief food for many larvae. Modern analytical techniques have demonstrated that the shallow waters (epipelagic zones) of many temperate and tropical seas are dominated by nanoplankton, both in terms of numbers of individuals and amount of photosynthesis. In the tropics, nanoplankton may account for more than 80 per cent of photosynthetic activity in open ocean waters. In coastal (neritic) waters, nanoplankton play a less important role.

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Ego Evolution

Ego Evolution

The Reasons Behind And The Plan To Build A Healthy Ego. It is important for us all to ensure that our egos are strong and healthy. Our ego is our identity. It is who we believe ourselves to be and as such is a reference point and our “home in the world.” The ego is individuality. As our identity it sets us apart from other people’s identity. Get your ego in order here.

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