An individual particle analysis and budget study of Onondaga Lake sediments1

Abstract

The sedimentation of particles in Onondaga Lake, N.Y., was examined by scanning electron microscopy with automated image analysis and X‐ray energy spectroscopy (SAX), a technique of individual particle characterization. The composition of the particles coming into the lake and those present in the sediments was analyzed to calculate an annual sediment budget. An allochthonous sediment input of 21,800 tonnes·yr−1 and a sediment output of 3,300 tonnes·yr−1 were calculated from flow rates, sediment loads, and concentrations. A sediment mass budget yielded an autochthonous sediment formation of 15,900 tonnes·yr−1 and a net sedimentation of 34,500 tonnes·yr−1. Calcite particles comprised a majority of these autochthonous sediments and were found in the epilimnion. In addition, measurable amounts of iron sulfide were formed in the hypolimnion. Such budgets provide information, based on different particle classes, for studies of particle formation, transport, and deposition processes in limnetic environments.