Long Island Sound has suffered from hypoxia for decades: Result of Global Warming? Eutrophication? It has always been like this…...

EAST LIS CENTRAL LIS WEST LIS NARROWS

Sampling mud

Design “proxies” for paleo- environmental research such as Salinity Temperature Faunal/floral characteristics Oxygen saturation Metals Sewage Calibrate proxies for these parameters on the modern LIS environment

Ragweed pollen Onset of hatting industry Chestnut blight 137 Cs 210 Pb 14 C

HG 137CS

MEASURES OF ORGANIC PRODUCTIVITY: BURIAL RATE OF ORGANIC CARBON BURIAL RATE OF DIATOM “SKELETONS” (BIOGENIC SILICA) PRODUCTION RATE OF HETEROTROPHS LIKE FORAMINIFERA

C org, %

Elphidium excavatum

The  13 C values in foram “shells” are related to mixing of sea and river water (salinity) and to addition of “light carbon” from photosynthetic productivity

Estimate  13 C variability not related to mixing of sea and river water (  13 C*) Measure  18 O values in foraminiferal shells Calculate  18 O of water using BWT Estimate salinity from LIS mixing model Estimate  13 C of dissolved inorganic carbonate using the LIS mixing model Subtract calculated - observed values:  13 C * =  13 C carbonate -  13 C calculated in water

Core data

% organic Carbon and  13 C* Year AD CORE A1C1

The  13 C* value indicates the amount of oxidized C org that was added to the bottom water column. The  13 C* value serves as an indirect proxy for OCI or Oxygen Consumption Index (Level of Paleo Oxygenation)

CONCLUSIONS (1) Major environmental changes in the early 1800’s: Increased C org and Bsi storage Isotopically lighter carbon, lower O 2 levels in bottom waters, sewage indicators, and metal pollutants Increased productivity of benthic foraminifera

CONCLUSIONS (2)