SBC LTER: Reef: Kelp Nitrogen uptake in Carpinteria and Mohawk kelp forests, 2016-2017

A large on-going time-series monthly water samples have been taken at
1m, 5 m and 10 m depth from the offshore edge of five kelp forests
near Santa Barbara, CA, USA (Arroyo Burro, Arroyo Quemado,
Carpinteria, Mohawk, Naples). See dataset: http://sbc.lternet.edu/cgi-bin/showDataset.cgi?docid=knb-lter-sbc.10 . Two datasets are presented here. One is a field study conducted in two
of the sites (Mohawk or Carpinteria) to test the N uptake of giant
kelp ( Macrocystis pyrifera ) and phytoplankton
from May 2016 to October 2017. In situ rates of urea, ammonium and
nitrate uptake by giant kelp blades and phytoplankton, which were
enclosed together within polyethylene blade bags, from the surface
canopy of Mohawk or Carpinteria kelp forests. The second dataset has
the results of laboratory experiments for testing the direct uptake of
urea by whole blades and natural phytoplankton communities entrained
in surface canopy waters.