Lance Lesack

Lance Lesack’s research has focused on limnological, biogeochemical, and hydrological processes in lakes, large rivers, and streams. He has particular interest in the ecology of floodplain lakes associated with major world rivers, ranging from their basic hydrology to their food-web configurations and energy sources sustaining them. Past work has involved rivers in West Africa and the Amazon. His present efforts are focused on lakes in the Mackenzie River Delta (western Canadian arctic) and the responses of this system to the multiple stresses of global change.

Lakes associated with large river floodplains are among the most hydrologically complex, biologically productive, and biodiverse freshwater habitats in the world. They also face a wide range of threats and remain poorly understood because such systems represent vast areas of habitat world-wide, and global change is modifying the complex water level regimes that created these systems. The Mackenzie Delta is the second largest river oodplain (13,000 km2, 45,000 lakes) of the circumpolar Arctic coast, and a key ecosystem of the Canadian north because it functions as a biological hotspot relative to the surrounding Arctic landscape. Lesack’s long-term goal is to tease apart the varied mechanisms that create such complex aquatic ecosystems and understand how such systems may respond resiliently or in surprising ways to multiple stresses of global change.

The International Polar Year (2007-2009) led to expansion of Lesack’s Mackenzie Delta research and an on-going collaborative project to improve understanding of riverine nutrient uxes from the great Arctic rivers to the rapidly changing ocean.