algae/ukl2006/haze.html

Observation of Surface Haze on Upper Klamath Lake,

John Rueter
August 26, 2006

Initial Obseravation

On August 3, 2006 I was driving north along HWY 97 and observed a haze that looked like it was coming from the lake. The patterns of the haze formation looked to me more like it was being generated by the lake than it was coming from forest fires or dust production from the hiway project on the west side of the lake.

Possible link to blooms

It is possible that this haze was caused, in part, by DMS released by the algal bloom. Some facts are given below that support this possible explanation.

• In the Frasier Valley, British Columbia, they observe what they call a "white haze" that is caused by ammonia from agriculture mixing with DMS that originates in the Straight of Georgia (annon 2000).
• Freshwater cyanobacteria have been shown to produce DMS in a shallow eutrophic lake in Washington with a maximum in August (Mechard and Rayburn 1979).
• Three Italian Lakes showed a maximum DMS production in late summer (Grone 1997).
• Release of DMS may be higher during times of bloom senescence, grazing or viral lysis (see references in Lee et al 2004 and Norris 2003).
• DMS metabolism has also been hypothesized to be part of a anti-oxidant and high light response of the algae as well as a possible anti-grazing response. All three of these (radical chemisty, high light and grazing) are important stressors for AFA in UKL.
• In seawater tanks, DMS was 7 to 26 times higher during algal bloom senescence (Nguyen et al 1988).

Other related observations

During several of our transects of Howard Bay (aka Wocus Bay) of Upper Klamath Lake Rich Miller and I observed concentrations of sea birds at a very specific area of the bay. When we looked at this area more closely it had high algal biomass and productivity. It could be that these birds are using DMS production as a cue as has been shown in the ocean (references in Hay and Kubanek 2002).

I am currently surveying people who work on the lake to see if anyone has smelled DMS during these bloom events. The "distinct smell of DMS" was one of the cues that motivated Lee et al. 2004 to investigate the distribution in Lake Bonney (Antarctica) even though there had been very few observation of DMS in freshwater systems. DMS is reported to smell like "cooked vegetables/corn/cabbage or shellfish/seafood" (http://www.homebrewzone.com/dimethyl-sulfide.htm).

Significance and further work

DMS is a strong ecological-chemical cue that can tie together seemingly disparate processes from light reflection to coyote behavior on shore across space scales of hundreds to thousands of kilometers (Hay and Kubanek 2000). A key question in UKL is whether there is a connection between the "crash" of algae in different areas of the lake and whether these events can be predicted.

We need to start paying attention to these other cues to ecosystem processes including bird distribution and smell. We should also examine the air quality data in this region to see if there is any evidence of sulfur containing aerosol particulate in August.

References

annon (2000). Georgia Basin Ecosystem Initiative Progress Report.

Grone, T. (1997). "Volatile organic sulfur species in three North Italian lakes: seasonality, possible sources and flux to the atmosphere." Mem. Ins. ital. Idrobiol. 56: 77-94.

Hay, M. E., and Julia Kubanek (2002). "Community and ecosystem level consequences of chemical cues in the plankton." Journal of Chemical Ecology 28(10): 2001-2016.

Lee, P. A., John C. Priscu, Giacomo R. DiTullio, Sarah F. Riseman, Nicole Tursich, and Stephen J. de Mora (2004). "Elevated levels of dimethylated-sulfur compounds in Lake Bonney, a poorly ventilated Antarctic lake." Limnol. Oceanogr. 49(4): 1044-1055.

Mechard, and ?.?. Rayburn (1979). Journal of Phycology 15: 379-383.

Nevitt 2000 ( in Hay and Kubanek --- get)

Nevitt et al 1995 ( in Hay and Kubanek --- get)

Nguyen, B. C., S. Belviso, N, Mihalopoulos, J. Gostan, and P. Nival (1988). "Dimethyl sulfide production during natural phytoplankton blooms." Marine Chemistry 24(2): 133-141.

Norris, K. B. (2003). Dimethylsulfide Emission: Climate control by marine algae? 2006.

Yoch, D. C. (2002). "Dimethylsulfoniopropionate: Its sources, role in the marine food web, and biological degradation to dimethylsulfide." Applied Environmental Microbiology 68(12): 5804 - 5815.