II. COASTAL ARCTIC TUNDRA ECOSYSTEM - 

 A LANDSCAPE UNIT 



The coastal plain of northern Alaska forms a relatively large and uniform landscape unit in 

 which the structure and function of the wet arctic tundra ecosystem can be elucidated. The region 

 is characterized by numerous lakes of all sizes, small ponds, and low-growing grass and sedge 

 tundra. It extends from west to east across some 900 kilometers and is 180 km wide in its widest 

 north-south extent. Relief is subdued, with elevations near sea level along the coast and rising 

 gently southward to 200 m at the contact with the foothills. Permafrost underlies the entire region 

 from within Vz to 1 m of the surface to over 300 m depth; the exceptions are under deep lakes and 

 major river channels which are free of permafrost in the upper zone. Actively forming polygonal 

 ground is common throughout, with a variety of forms expressed. Drainage is poorly integrated. 

 Small meandering streams and tundra-covered beaded streambeds are common. Lakes of varying 

 depths and dimensions cover as much as 50-80% of the land surface in some portions of the coastal 

 plain. Summer climate is coolest along the coast and warms inland. Conversely, winter climate 

 is more severe inland. The warmer inland summer climate is reflected in the vegetation. Along 

 coastal areas such as Barrow approximately 100 vascular plants are found, while inland the number 

 increases abruptly due to an increase in the variety of habitats as well as a more moderate summer 

 climate. 



BARROW RESEARCH DESIGN 



Jerry Brown* USA CRREL 



Larry Tieszen* Augustana College 

 Steve MacLean* Univ. of Illinois 



Previous studies have shown that the fauna and flora are considerably less diverse than in 

 inland coastal locations. Because of this,ecosystem interactions are fewer and, possibly, more 

 easily defined. In addition, it is generally believed that "simple" ecosystems are inherently 

 less stable than more complex systems, and include fewer potential mechanisms for adjustment 

 following disruption or stress. These reasons make the Barrow ecosystem particularly appropriate 

 for a first attempt at integrated ecosystem research and modeling. Figure 2 is an index map of 

 the Barrow area, showing the locations of major study sites involved in this report. 



The Barrow tundra encompasses a complex of habitats distributed along a moisture-dominated 

 gradient related to microtopography and land forms. While the need was recognized to determine 

 the range of biolc^ical and abiotic parameters associated with this complete range of habitats, 

 the resources and personnel available in 1970 did not permit a complete study of the entire spec- 

 trum of tundra variation. Instead, attention was concentrated on a relatively homc^eneous, terres- 

 trial intensive study site (site 2; see Fig. 3) which represents a mid-point along this gradient. 

 Control plots on the intensive site (2) were used to provide data on the seasonal precession of 

 ecosystem parameters for the undisturbed tundra. These data will form the major input or valida- 

 * Principal authors 



