Leaves Accumulated in Lake with Canoe (image) Cary Institute of Ecosystem Studies Share Print E-Mail Caption Terrestrially derived organic matter accumulates in freshwater lakes. Maple leaves fall off trees in autumn and are blown and washed into lakes where they are fed upon by aquatic animals. Credit Andrew Tanentzap Usage Restrictions To promote this press release. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.