Angelo Coast Range Reserve

01 Aug, 05 AM - 31 Aug, 05 AM

The project will include 2 components. In the first, we will investigate nutrient (nitrogen and phosphorous) limitation of algae within the watershed using nutrient-diffusing substrates. This portion of the project has 3 goals: 1) to determine which nutrient is generally more limiting within the watershed; 2) to determine if there is a relationship between stream size (watershed area) and nutrient limitation; and 3) to determine if there is variation among streams of similar size in the degree of nutrient limitation. We will investigate these questions by placing nutrient-diffusing substrates at 9 stream sites for one month, then analyzing the biofilms that have grown on them. The substrates will be constructed of 6 in diameter clay pots filled with agar, and glued to a petri dish with aquarium sealant. Each substrate will be placed on a small vaseline covered pedistal to defend the growing biofilm from herbivores. The pedistal will be constructed of a deli container filled with sand. Twenty substrates will be placed at each site, divided into 4 nutrient treatments. The treatments will consist of nitrate addition (NaNO3), phosphate addition (KaHPO4), addition of both nutirents, or control (no nutrients). The nutrients will be added to the agar and will diffuse out through the clay pots. The amounts added should not measurably increase the nutrient load in the streams. The stream sites will include streams ranging in size from 0.5 square kilometer drainage area to over 100 square kilometer drainage area (McKinley, Skunk, Fox, Barnwell, Jack of Hearts, and Elk Creeks, 2 sites on Elder Creek, and the South Fork Eel River (Jane's)). At the end of the one month incubation period, substrates will be scraped to remove biofilms, and the biomass, chlorophyll content, C:N:P ratios, and other variables will be determined. This will allow us to determine where in the watershed algae experience nutrient limitation, and how the severity of such limitation varies. The study may be repeated for a second 1 month incubation period, depending on initial results, to dtermine whether such patterns vary seasonally. During the second portion of the study, we will investigate interactions between algae and bacteria within biofilms. We will try to determine whether bacteria and algae compete for nutrients or space, and whether algae support bacterial growth through excretion of polysaccharides bacteria may use for food. We will use similar substrates to those described above, but the treatments will be different and a smaller number of sites will be used. Each of the following materials will be added to 6 substrates per site: nothing (control) NaNO3 (nitrate addition) antibiotic (Maracyn plus and Maracyn 2) algicide glucose (bacterial food suppliment) glucose + nitrate antibiotic + nitrate algicide + nitrate algicide + glucose algicide + glusoce + nitrate We will delpoy at total of 66 substrates/site for one month. The sites will include a sunny stream (Elder Creek near confluence with South Fork Eel River) and a shady stream (Fox Creek). At the end of the deployment we will determine the total biomass, chlorophyll content, and numbers of algal and bacterial cells present within the biofilms. This will allow us to determine whether bacteria and algae compete for nutrients and/or space, whether bacteria are limited by food rather than nutrients, and if algae benefit bacteria. We will also be able to determine whether these interactions may differ between sites with different growth conditions for algae and bacteria.

Visit #6207 @Angelo Coast Range Reserve

Approved

Under Project # 4409 | Research

Nutrient diffusing substrate experiments

volunteer - Eastern Washington University

Reservation Members(s)

Group of 4 Graduate Student Aug 1 - 31, 2004 (31 days)

Reserve Resources(s) | Create Invoice

Computer lab 4 Aug 1 - 31, 2004
Fox Creek Lodge 4 Aug 1 - 31, 2004
Lab 4 Aug 1 - 31, 2004
Wilderness Lodge 4 Aug 1 - 31, 2004