Impacts of Ocean Acidification on Sediment Processes in Shallow Waters of the Arctic Ocean

International audienceDespite the important roles of shallow-water sediments in global biogeochemical cycling, the effects of ocean acidification on sedimentary processes have received relatively little attention. As high-latitude cold waters can absorb more CO 2 and usually have a lower buffering capacity than warmer waters, acidification rates in these areas are faster than those in subtropical regions. The present study investigates the effects of ocean acidification on sediment composition, processes and sediment-water fluxes in an Arctic coastal system. Undisturbed sediment cores, exempt of large dwelling organisms, were collected, incubated for a period of 14 days, and subject to a gradient of pCO 2 covering the range of values projected for the end of the century. On five occasions during the experimental period, the sediment cores were isolated for flux measurements (oxygen, alkalinity, dissolved inorganic carbon, ammonium, nitrate, nitrite, phosphate and silicate). At the end of the experimental period, denitrification rates were measured and sediment samples were taken at several depth intervals for solid-phase analyses. Most of the parameters and processes (i.e. mineralization, denitrification) investigated showed no relationship with the overlying seawater pH, suggesting that ocean acidification will have limited impacts on the microbial activity and associated sediment-water fluxes on Arctic shelves, in the absence of active bio-irrigating organisms. Only following a pH decrease of 1 pH unit, not foreseen in the coming 300 years, significant enhancements of calcium carbonate dissolution and anammox rates were observed. Longer-term experiments on different sediment types are still required to confirm the limited impact of ocean acidification on shallow Arctic sediment processes as observed in this study

Bangor Hydro Electric News: October 1939: Volume 9, No.10 -- Athletics, University of Maine Issue

Dozens of photographs of the University of Maine, Orono, campus from 1939. Also, photographs of men\u27s and women\u27s athetics at the university, including a team photo of the 1939 football team, action scenes of the Bates-U-Maine football game, and pictures of women\u27s field hockey and tennis action. In a separate section, a Bangor electrical crew installs underground cables in downtown Bangor.https://digicom.bpl.lib.me.us/bangorhydro_news/1011/thumbnail.jp

Repairs to Medway Dam, 1954-1955

Photographs show repairs being made to the Medway Dam on the Penobscot River from May 1954 to September 1955.https://digicom.bpl.lib.me.us/bangorhydro_linework/1003/thumbnail.jp

Program for the 9th Annual Meeting of the Quarter Century Club of the Bangor Hydro Electric Company

The program for the 9th annual meeting of the Quarter Century Club of the Bangor Hydro Electric Company. The Quarter Century Club was open to members of the Bangor Hydro Electric Company with over 25 years of service to the company. Event was on April 24, 1945, at the Penobscot Valley Country Club in Orono, Maine. Photographs of eighty-one employees with the quarter century of service are featured. Turkey and stuffing were on the menu.https://digicom.bpl.lib.me.us/bangorhydro_news/1053/thumbnail.jp

Bangor Hydro Electric News: December 1938: Volume 8, No.12 -- Christmas Issue

The good old Christmas spirit burst upon the Company in full force as the excited voices of 170 children echoed though offices and halls. Christmas carols, the hum of mechanical toys, and gay notes from many harmonicas seemed to blend into one happy Yuletide song as the management of Hydro entertained the children, from 2 to 12 years of age, of all divisions in the Bangor division. Many photographs from the party are included, as is the original invitation to the staff party.https://digicom.bpl.lib.me.us/bangorhydro_news/1021/thumbnail.jp

Bangor Hydro Electric News: August 1936, Volume 5, No.8 -- Annual Employee Outing Issue

Describes the festivities of the annual employee outing/retreat at Lucerne-In-Maine. Also includes reprints of an August 27, 1936, Bangor Daily News article detailing Bangor Hydro forming the first mobile relief unit in the state and the second in the entire United States.https://digicom.bpl.lib.me.us/bangorhydro_news/1032/thumbnail.jp

Bangor Hydro Electric News: April 1937: Volume 6, No.4, Quarter Century Club Issue

Profiles dozens of long-time employees of the Bangor Hydro Electric Company.https://digicom.bpl.lib.me.us/bangorhydro_news/1030/thumbnail.jp

Bangor Hydro Electric News: November 1928, Volume 1, No.12 -- General Office Personnel Issue

Provides biographical and work history profiles for over two dozen employees of the Bangor Hydro Electric Company. Also includes photographs and a lengthy description of a canoe trip along the East Machias River by employees of the company.https://digicom.bpl.lib.me.us/bangorhydro_news/1045/thumbnail.jp

Bangor Hydro Electric News: June 1929, Volume 2, No.7 -- Managers Issue

Provides extensive biographical information about Lincoln A. Gardner, Ralph A. Fernald, Albert E. Grose, William R. Wray, Leonard A. Austin, Roscoe H. Smith, Vernon E. Cushing, Leroy G. Vose, and Julius W. McDonald, managers at Bangor Hydro Electric offices across the state.https://digicom.bpl.lib.me.us/bangorhydro_news/1041/thumbnail.jp

Bangor Hydro Electric News: October 1937: Volume 6, No.10: Carbarn Number

Covers the history of the carbarn [the garage for the street cars of the Bangor Street Railway] as well as featuring several pictures of the workers responsible for every aspect of the street cars, from the stockkeeper to the iron workers to the blacksmith to the electricians and the carpenters and the mechanics.https://digicom.bpl.lib.me.us/bangorhydro_news/1019/thumbnail.jp