NUTRIENT BALANCE IN THE WESTERN ENGLISH-CHANNEL

Over a 10 yr period the waters of the western English Channel always contained significant quantities of dissolved N and P. As 1 form of nutrient such as nitrate was exhausted there was usually an increase in 1 of the other N fractions such as the organic. Some species of phytoplankton directly utilize organic N compounds. As the nitrate is exhausted the phytoplankton population may change such that species capable of utilizing other forms of N become dominant. This need not involve a drop in total productivity and thus throws doubt on the classical theory of nutrient-limiting growth.