The limnological study of Toolik Lake began in the Summer of 1975. This research was an outgrowth of the arctic IBP project which had focused mainly on small Arctic pond ecosystems on the Alaskan Arctic coastal plain. It was thought desirable to study larger, deeper lakes which contained fish to further generalizations developed during the IBP study. Initial research on Toolik Lake and the surrounding lakes and ponds focused on process studies such as annual primary productivity of the lake or the vertical migration patterns of the resident zooplankton. In 1983 the philosophy of the research changed with the funding of a more integrated programme. The fundamental question posed was whether Arctic lake and stream ecosystems are regulated from the bottom up by nutrient availability or from the top down by the density and activity of top predators. In 1987 the Toolik Lake area was designated an LTER (Long-Term Ecological Research) site, one of 18 such sites throughout the United States, Puerto Rico and the Antarctic. The research theme for the Arctic LTER also focuses on the regulation of Arctic ecosystems, whether regulation comes from the top down or bottom up. The Arctic LTER also incorporates a terrestrial component as well as a lake and stream component.

Phytogeographically and climatically West Greenland includes parts of the low arctic and high arctic areas. The present vegetation and a summary of its history since the last glaciation based on pollen and macrofossil analyses are briefly described. The determination of more than 55,000 herbarium sheets of native phanerogams has been checked. Before preparing the dot maps it was necessary to decide at which level taxonomically difficult genera (eg: Antennaria, Draba, Poa, Puccinellia, and Stellaria would be treated). For all of these the criteria used are given. Dot maps have been prepared for 379 taxa. These maps have been grouped into 11 West Greenland distribution types, which clearly correlate with T W Böcher's biological distribution types (Böcher 1963). The collecting intensity in the large area is rather uneven. This is illustrated by a map giving the number of collections at the 305 localities from which 50 or more collections are at hand. Another map giving the number of taxa at 29 well-investigated localities illustrates the species diversity in the region. Most low arctic localities have more than 130 taxa, with 215 at the richest locality (Godhavn / Qeqertarsuaq on Disko), while the number at no high arctic locality exceeds lS0. Reference to the corresponding numbers in other parts of Greenland is given. Based on the dot maps a new delimitation of West Greenland in floristic provinces and districts is presented. It differs somewhat from that in Grønlands Flora / The Flora of Greenland (Böcher et al. 1957, and later editions). The major alteration is that the boundary between the low and high arctic phytogeographic provinces is now placed through north Disko - Nuussuaq. As a consequence of this the southernmost district in the high arctic is divided into an outer (NWso) and an inner province (NWsi). Minor alterations are suggested in the southern part of West Greenland.