Li undertook postdoctoral training at the Bigelow Laboratory for Ocean Sciences under Ian Morris, and also at the Woods Hole Oceanographic Institution under Joel C. Goldman.
[7] Notably, the putative existence of these very small chlorophyll-bearing cells had been predicted by Li's co-author John Cullen in their multi-authored 1983 paper in which the deduction of "invisible photoautotrophs" was made based on "excess chlorophyll" as one possibility to reconcile the biomass budget of phytoplankton in the tropical Pacific Ocean [3] Li developed methods and ideas that tried to integrate flow cytometric measurements of ocean microbes within general ecological concepts,[8][9] eventually into what he called cytometric macroecology.
[10] In collaboration with Eddy Carmack, Fiona McLaughlin, Connie Lovejoy, and others, Li showed that this approach was useful in documenting changes in the ecology of plankton microbes in the Arctic Ocean as the waters there warm and freshen[11][12] In 1992, Li established an oceanographic monitoring station in the Bedford Basin of Halifax Harbour as a sentinel for long-term change in the pelagic environment of coastal waters in Atlantic Canada.
The Bedford Basin Monitoring Program was designed to make weekly measurements of selected properties that characterize the physical, chemical, biological and optical environments of the water column.
[16][17][18] The citation for this award [19] noted that "Li's work has created an important new body of knowledge on growth measurement and the effects of temperature changes on plankton".