Contact Information
Institute of Marine Science234 Irving II
P.O. Box 757220
University of Alaska Fairbanks
Fairbanks, AK 99775-7220
Phone: (907) 474-7229
terry@ims.uaf.edu
Terry Whitledge Professor
Specialties
- marine chemistry/chemical ceanography
- nutrient chemistry
- nitrogen cycle
- biogeochemical processes
- dynamics of coastal ocean and estuaries
- eutrophication and oxygen depletion
- nutrient uptake and regeneration
- harmful algal bloom
Research Overview
- The variation of freshwater inflow into South Texas bays and estuaries is being examined to document the effects upon the biological communities. Monthly measurements of hydrography, nutrients and primary productivity are collected in the Nueces/Corpus Christi Estuary to estimate the enhancement of biological productivity created by freshwater releases.
- The appearance of a "brown tide" algal bloom that has persisted for more than seven years changed the clear waters of Laguna Madre to a dark brown color. Samples are collected in upper and lower Laguna Madre to monitor the severity of the bloom conditions and to relate the distribution of the organism to physical, chemical and biological processes. The appearance of persistent algal blooms have become more common in the U.S. and internationally during the past ten years. We are working with the National Assessment of Nutrient Enrichment and Ecology of Harmful Algal Bloom (ECOHAB) programs of NOAA to better understand why these blooms are fouling coastal and estuarine waters, contaminating sea food and killing marine fish and mammals.
- More than 50% of the area of the U.S. drains into the Mississippi/Atchafalaya River which has a greatly increased organic and nutrient load as a result of human population increases and widespread use of fertilizers. The resulting nutrient overenrichment of the river has created areas of low oxygen near the bottom on the Gulf of Mexico continental shelf. We are studying the distribution of nutrients and their uptake by phytoplankton near the river delta and their later regeneration in the zone of low oxygen.
- The Chukchi Sea north of Bering Strait receives northward flowing water from the North Pacific Ocean after transiting the Bering Sea. These waters contain large quantities of nutrients which promote very high primary production rates and ultimately feed the large populations of seals, whales and walrus. However, these coastal waters of Alaska are undergoing dramatic changes with respect to contamination and over-harvesting and are important in assessing the extent of greenhouse warming and climate change. The atmospheric transport of pesticides and other chemicals into the Arctic accumulates in ice and later in organisms as they progress up the food chain. Russian and American scientists are cooperating in programs to investigate the ecology of the Bering/Chukchi Seas and to determine the changes that may be occurring due to human activities.
Links
Selected Publications
Walsh, J.J., D.A. Dieterle, F.E. Muller-Karger, K. Aagaard, A.T. Roach, T.E. Whitledge, and D.A. Stockwell. 1997. CO2 cycling in the coastal ocean. II. Seasonal organic loading of the Arctic Ocean from source waters in the Bering Sea. Cont. Shelf Res. 17:1-36.
Cooper, L.W., T.E. Whitledge, J.G. Grebmeier, and T. Weingartnere. 1997. Nutrient, salinity and stable oxygen isotope composition of Bering and Chukchi Sea waters in and near the Bering Strait. J. Geophys. Res. 102:12563-12574.
Boesch, D.E., D.M. Anderson, R.A. Horner, S.E. Shumeway, P.A. Tester, and T.E. Whitledge. 1997. Harmful algal blooms in coastal waters: options for prevention, control and mitigation. NOAA Coastal Ocean Program, Decision Analysis Series No. 10., Silver Spring, MD, 49pp.
Whitledge, T.E. and D.A. Stockwell. 1995. The effects of a mandated freshwater releases on the nutrient and pigment environment in Nueces Bay and Rincon Delta. In: Proceedings of 24th Water for Texas Conference, Texas Water Research Institute, College Station, TX, pp. 47-51.
Pakulski, J.D., R. Benner, R. Amon, B. Eadie and T.E. Whitledge. 1995. Community metabolism and nutrient cycling in the Mississippi River plume: Evidence for intense nitrification at intermediate salinities. Mar. Ecol. Prog. Ser. 117:207-218.