For so many years, the dioxide or radioactive carbon based measurements of primary productivity or of standing crop were taking place from ships at space sampling stations. The changes in the environment as the ship steamed from one station to the next could not be evaluated, nor were the facts between the stations that were examined. Therefore, it is only right to assume that the information gathered at the sample stations could be mediocre compared to areas between stations and between sampling period. The intricacy and richness of small to moderate spatial variations in the abundance of phytoplankton were missed, since the day to day variations occurring at any sampling station.
Contrary to ship based sampling, utilizing the satellites, the scientist will have a general and immediate overview of a large part of ocean. The satellites do not have the capacity to directly measure the marine primary productivity, instead, the surface color of the ocean is determined using the coastal zone color scanner inside the weather satellite. After that, the ocean color measurements are employed together with the mark from ship based measurements. This is to estimate the standing crops of phytoplankton and their growth rates and to conclude shipboard productivity measurements to large oceanic areas. Eventually, there is possibility to use solely the coastal zone color scanner information in estimating the primary production or growth rates.
With the use of satellite, the remote sensing of ocean color is the first method to calculate the marine primary productivity on a global scale with ample resolution to allow analyses of phytoplankton changes over time scales of weeks or years.
Ever since the coastal zone color scanner was launched into orbit, the satellite imagery has modernized our view of the patterns of primary productivity in the ocean. The dispersal patterns of phytoplankton are multifaceted and display some similarities with the sea surface temperature distributions. For instance, people come to know the patches and eddy of phytoplankton and they truly become common. In some upwelling portions, the squirts or plumes of phytoplankton rich water extend offshore. A few years ago, these chief elements of marine phytoplankton distribution were totally alien for us.
The Elements Surrounding
the Primary Production

The maintaining production of natural materials by marine phytoplankton relies on a set of network of biotic and abiotic conditions. If there is unlimited factors essential for the growth of phytoplankton like nutrients, sunlight, and space, the population sizes of this marine organisms boost up in greater size.
By nature, the populations of phytoplankton do not go on to grow unchecked. Instead, their sizes are restricted by their so called tolerance threshold to particular factors in their environment or may be by the availability of substances for which there is a least need. Any state that above the limits of tolerance or does no longer satisfy the main material necessary for the organisms to establish a check on further population growth is coined as limiting factor.
The populations of phytoplankton are restricted by one or combinations of these elements that force them to deviate the exponential growth. The essential elements for phytoplankton are light, nutrients, availability and herbivore grazing.