Plant Life Studies - Marine and Terrestrial

[Astronuc]

The Earth's landscapes and oceans are teeming with life—millions of species. Of particular interest to remote sensing scientists are those land- and marine-based plants that photosynthesize because they draw carbon dioxide from the atmosphere. Using satellite and surface-based measurements, scientists seek to better understand our world's carbon cycle. Worldwide, what are the major "sources and sinks" of carbon?

http://earthobservatory.nasa.gov/Topics/life.html

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Phytoplankton - http://earthobservatory.nasa.gov/Library/Phytoplankton/

Phytoplankton are microscopic plants that live in the ocean. There are many species of phytoplankton, each of which has a characteristicshape. Collectively, phytoplankton grow abundantly in oceans around the world and are the foundation of the marine food chain. Small fish, and some species of whales, eat them as food. Larger fish then eat the smaller fish. Humans catch and eat many of these larger fish. Since phytoplankton depend upon certain conditions for growth, they are a good indicator of change in their environment. For these reasons, and because they also exert a global-scale influence on climate, phytoplankton are of primary interest to oceanographers and Earth scientists around the world.
 
Like their land-based relatives, phytoplankton require sunlight, water, and nutrients for growth. Because sunlight is most abundant at and near the sea surface, phytoplankton remain at or near the surface. Also like terrestrial plants, phytoplankton contain the pigment chlorophyll, which gives them their greenish color. Chlorophyll is used by plants for photosynthesis, in which sunlight is used as an energy source to fuse water molecules and carbon dioxide into carbohydrates—plant food. Phytoplankton (and land plants) use carbohydrates as "building blocks" to grow; fish and humans consume plants to get these same carbohydrates.

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http://earthobservatory.nasa.gov/Library/Coccolithophores/

Like any other type of phytoplankton, coccolithophores are one-celled marine plants that live in large numbers throughout the upper layers of the ocean. Unlike any other plant in the ocean, coccolithophores surround themselves with a microscopic plating made of limestone (calcite). These scales, known as coccoliths, are shaped like hubcaps and are only three one-thousandths of a millimeter in diameter.

What coccoliths lack in size they make up in volume. At any one time a single coccolithophore is attached to or surrounded by at least 30 scales. Additional coccoliths are dumped into the water when the coccolithophores multiply asexually, die or simply make too many scales. In areas with trillions of coccolithophores, the waters will turn an opaque turquoise from the dense cloud of coccoliths. Scientists estimate that the organisms dump more than 1.5 million tons (1.4 billion kilograms) of calcite a year, making them the leading calcite producers in the ocean.

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http://earthobservatory.nasa.gov/Study/Coccoliths/bering_sea.html
Changing Currents Color the Bering Sea a New Shade of Blue

[Astronuc]

The Large-scale Biosphere-Atmosphere Experiment in Amazonia

http://earthobservatory.nasa.gov/Study/LBA/

With tributaries extending from the vast savannas to its north and south, the Amazon River runs almost 4,000 miles (1 mile equals 1.6 kilometers) across northern South America from the highland biomes in the foothills of the Andes Mountains to the Atlantic Ocean. It carries twenty percent of all river water discharged into Earth’s oceans—ten times the volume of the Mississippi River. If the Amazon River Basin were draped over the continental United States, it would cover more than three fourths of the country.