In situ studies of algal biomass in relation to physicochemical characteristics of the Salt Plains National Wildlife Refuge, Oklahoma, USA

• Published in: Saline systems 2005-12, Vol.1 (1), p.11-11, Article 11
• Main Authors: Major, Kelly M, Kirkwood, Andrea E, Major, Clinton S, McCreadie, John W, Henley, William J
• Format: Article
• Language: English
• Subjects: Marine
• ISSN: 1746-1448; 1746-1448
• DOI: 10.1186/1746-1448-1-11

This is the first in a series of experiments designed to characterize the Salt Plains National Wildlife Refuge (SPNWR) ecosystem in northwestern Oklahoma and to catalogue its microbial inhabitants. The SPNWR is the remnant of an ancient ocean, encompassing approximately 65 km2 of variably hypersaline flat land, fed by tributaries of the Arkansas River. Relative algal biomass (i.e., chlorophyll concentrations attributed to Chlorophyll-a-containing oxygenic phototrophs) and physical and chemical parameters were monitored at three permanent stations for a one-year period (July 2000 to July 2001) using a nested block design. Salient features of the flats include annual air temperatures that ranged from -10 to 40 degrees C, and similar to other arid/semi-arid environments, 15-20-degree daily swings were common. Shade is absent from the flats system; intense irradiance and high temperatures (air and sediment surface) resulted in low water availability across the SPNWR, with levels of only ca. 15 % at the sediment surface. Moreover, moderate daily winds were constant (ca. 8-12 km h-1), sometimes achieving maximum speeds of up to 137 km h-1. Typical of freshwater systems, orthophosphate (PO(4)3-) concentrations were low, ranging from 0.04 to