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Example of a simplified nutrient cycle from Ecosystems Center 1979 annual report

Caption reads: "Figure 1. The biotic systems that have built and now maintain the biosphere also influence the cycles of carbon, nitrogen, sulfer, and other elements. The general pattern of movement is a series of exchanges between the atmosphere, the land, and the sea. Human activities worldwide have mobilized significant additional quantities of biotically important substances, including toxins, and have modified the natural cycles."

Created: 1979

A data logger at one of the Ecosystems Center's LTER sites

A Campbell CR21x data logger at one of the Ecosystems Center's LTER sites.

Lee Stuart cottongrass seed in Alaska

Lee Stuart (grad student from San Diego State/UC Davis) collecting Eriophorum (cottongrass) seed, late 1970s. The location is probably along the Elliot Highway north of Fairbanks, Alaska.

Researchers setting up greenhouse experiments at Toolik Lake, Alaska

Researchers setting up an early version of "greenhouse" experiments at Toolik Lake, Alaska.

A Sunday hike in the Brooks Range, Alaska

A Sunday hike in the Brooks Range, Alaska, about 1980-81. The woman is Barbara Lachenbruch (student of Terry Chapin's, Univ Alaska). Behind her is Tom and Ellen (last names unknown), working at Toolik Lake at the time.

Walt Oechel's early system for controlling variables in a field experiment

Walt Oechel's early system for controlling CO2/temperature/water/light in field cuvettes, on the hillside below our fertilizer plots.

Terry Chapin sorting cottongrass tillers in the field at Sagwon, Alaska

Terry Chapin sorting cottongrass tillers in the field at Sagwon, Alaska, late 1970s.

Jim Laundre, Anne Giblin, Gus Shaver, and Knute Nadelhoffer, in a snowstorm at Toolik Lake, July 18, 1984

Left to right: Jim Laundre, Anne Giblin, Gus Shaver, and Knute Nadelhoffer, in a snowstorm at Toolik Lake, July 18, 1984. Jim was then an RA, Anne, Gus, and Knute were Assistant Scientists, all at the Ecosystems Center.

Created: 1984

Note from David Kirchman to Ivan Valiela at the Ecosystems Center

Note reads: "Ivan- You & the MBL Marine Ecology course got me going in this field. Thanks. David Kirchman"

Created: 2013

Ecosystems Center researchers' model of nutrient flows in an estuarine ecosystem

Caption reads: "Figure 4: A diagrammatic model of carbon and nitrogen flow in an estuarine ecosysem that emphasizes inputs of organic carbon and nitrogen and inorganic nutrients from upland watersheds and processing by the estuarine food web. Compartments of the mathematical model are shown in the box. The inorganic nutrients compartment comprises both ammonium and nitrate. The organic matter compartment comprises three distinct components: labile nitrogenous material, labile carbohydrate material and refractory nitrogenous materal."

Created: 1993

Ecosystems Center researchers' figure of element cycles in terrestrial ecosystems

Caption reads: "Figure 3. Major element fluxes within terrestrial ecosystems."

Created: 1986

Map of Ecosystems Center researchers' forest watershed fertilizer study in Maine

Caption reads: "Figure 1: The dashed lines mark two catchments (watersheds) at the Bear Brooks Watersheds site in Maine. Both catchments are located on a southeast-facing slope and drained by streams that persist throughout the year (dark lines). The shaded catchment was treated with fertilized labeled with 15N during 1991; the other served as a control. Filled trianges show sampling locations in the fertilized area."

Created: 1992

Simulation of global annual net primary production from Ecosystems Center researchers' Terrestrial Ecosystem Model

Caption reads: "Figure 2. Annual net primary production (NPP) for undisturbed mature vegetation of the earth's ecosystems as determined by the Terrestrial Ecosystem Model (TEM) for current climate at atmosphereic carbon dioxide levels."

Created: 1992

Viktor Hamburger to Giuseppe Levi, July 8, 1946, English Letter

BW copy of original German letter

Created: 1946-07-08

Viktor Hamburger to Giuseppe Levi, July 8, 1946, German Letter

Handwritten english translation available

Created: 1946-07-08

Viktor Hamburger to John D. Decker, June 25, 1965

Hamburger writes to John Decker to inform him that the grant supplement for which he had required Decker's information has been sent off, and gives him information about the funding situation. Hamburger also asks Decker to make observations of turtle embryo motility so that it can be compared to that in the chick

Created: 1965-06-25

Viktor Hamburger to Sin-iti Asayama, May 19, 1960

Thank-you note for a recent visit to Japan of several weeks, and invitation for Asayama to visit Hamburger's laboratory

Created: 1960-05-19

Viktor Hamburger to Setsuya Fujita, September 1, 1964

Hamburger writes to Fujita to thank him for the reprints and ask him to visit his laboratory in St. Louis

Created: 1964-09-01

Robert Chambers portrait

Inscribed "Robert Chambers"

P. Reznikoff in the lab

Inscribed "P. Reznikoff"

I.H. Page in the lab

Inscribed "I.H. Page"

Eugene Dubois, 1934

Inscribed "Eugene F. DuBois, Dept. Med. Cornell, 1934"

Created: 1934

F. P. Knowlton, 1928

Inscribed "F.P. Knowlton, 1928"

Created: 1928

Ralph Lillie, 1922

Inscribed "Ralph Lillie, 1922"

Created: 1922