Open AccessEnhanced biological production in the southeastern Arabian Sea during spring intermonsoon
Author(s) -
C. M. Laluraj,
K.K. Balachandran,
P. Sabu
Publication year - 2012
Publication title -
advances in oceanography and limnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.387
H-Index - 16
eISSN - 1947-573X
pISSN - 1947-5721
DOI - 10.4081/aiol.2012.5330
Subject(s) - oceanography , water mass , hydrography , chlorophyll a , nitrate , bay , biogeochemical cycle , environmental science , salinity , geology , chemistry , biology , ecology , biochemistry
Hydrographic observations in the southeastern Arabian Sea (SEAS) have identified a warm (>30°C) and stratified water mass (stability >5 × 10−5 m−1) along the near shore area between 10°N and 15°N during spring intermonsoon. This water mass was relatively low saline (34.2) and nitrate-rich (0.5 µM), favoring moderate primary production (6.7 mg C m−3 d−1). Since the mixing of the Arabian Sea and the Bay of Bengal waters is an important process during this period, the enhanced primary production in the SEAS is attributed to the entrainment of unconsumed nitrate left over during the previous season from the northern Arabian Sea. The season was further characterized by the presence of a deep chlorophyll a maximum (0.5 mg.m−3) in the outer shelf below (>50 m) the subducted Arabian Sea High Saline Waters, which was photosynthetically less active (<1.5 mg C m−3 d−1) due to light limitation