An Organic Energy Budget for the New York State Barge Canal

Abstract

An annual energy budget is presented for the New York State Barge Canal, a first order man-made waterway in western New York. The ecosystem approach, in which all input and output of energy as organic matter are measured, is used to describe the energy flow in an 1130-meter segment of the canal. The annual input of energy to the system is 38.1 x 109 kcal/m2. Over 99% of this is allochthonous from upstream areas. Autochthonous input from primary producers accounts for less than 0.1% of the total energy available to the-system. Meteorologic inputs (litter and precipitation) from the adjacent terrestrial ecosystem account for less than 0.1% of annual energy input. Seventy-eight percent of the geologic input and 99% of the total energy input occur as dissolved organic matter. Approximately 7,790 kcal/m2 of organic detritus is stored within the system. The annual output of energy from the canal system is 38 x 109 kcal/m2. Ninety-nine percent of the annual energy input is exported to downstream areas in canal water. Less than 0.1% of the energy output is lost through community respiration. The New York State Barge Canal is a strongly heterotrophic system in which ecosystem efficiency and flow~through energy (0.1% and 99.9%, respectively} indicate the canal makes very little use of the energy supplied to it.