Standing biomass and production in water drainages of the foothills of the Philip Smith Mountains, Alaska

In the foothills of the Philip Smith Mountains, Brooks Range, Alaska, tussock tundra is the most widely distributed vegetation, and it occurs on rolling hills and in valleys that were shaped by a sequence of Pleistocene glaciations. In this study, aboveground standing biomass and production were compared in “intertrack tundra” areas that were relatively homogenous with respect to downslope drainage and adjacent “water tracks” that acted to channel water flow to the valley bottom stream. Comparisons of biomass, leaf area index, and specific leaf weight were also made between upper and lower slope positions. Similarities and differences of vegetation structure are examined with respect to graminoid, deciduous shrub, evergreen shrub, herbaceous, and bryophyte components. Water tracks were found to have 1.5–1.7 times the biomass of intertrack tundra, and production (excluding secondary growth) in water tracks was 40% greater than in intertrack tundra. The aboveground biomass for all areas studied and the annual production values were similar to those found in other studies of tussock tundra. While only slight differences in depth of thaw occurred in water tracks and intertrack tundra during June and early July, water tracks thawed more deeply with the onset of summer rains. Warmer temperatures at 40 cm depth in July and August may have increased nutrient availability, whereas greater rooting depth and movement of water may have increased nutrient capture in water tracks as compared with the intertrack areas. Greater biomass and a deeper thaw depth occurred at upper slope locations.

[1]  Donald A. Walker,et al.  Terrain, vegetation and landscape evolution of the R4D research site, Brooks Range Foothills, Alaska , 1989 .

[2]  W. Oechel,et al.  Comparative effects of downslope water and nutrient movement on plant nutrition, photosynthesis, and growth in Alaskan tundra , 1989 .

[3]  W. Oechel,et al.  THE EFFECTS OF TOPOGRAPHY AND NUTRIENT STATUS ON THE BIOMASS, VEGETATIVE CHARACTERISTICS, AND GAS EXCHANGE OF TWO DECIDUOUS SHRUBS ON AN ARCTIC TUNDRA SLOPE , 1988 .

[4]  F. Chapin,et al.  Productivity and Nutrient Cycling of Alaskan Tundra: Enhancement by Flowing Soil Water , 1988 .

[5]  D. Walker,et al.  Cumulative Impacts of Oil Fields on Northern Alaskan Landscapes , 1987, Science.

[6]  S. Hastings,et al.  Downslope fertilizer movement in arctic tussock tundra , 1987 .

[7]  F. Chapin,et al.  Effect of Fertilizer on Production and Biomass of Tussock Tundra, Alaska, U.S.A. , 1986 .

[8]  G. Shaver.  Woody Stem Production in Alaskan Tundra Shrubs , 1986 .

[9]  F. Stuart Chapin,et al.  Individualistic Growth Response of Tundra Plant Species to Environmental Manipulations in the Field , 1985 .

[10]  D. Schimel,et al.  Biogeochemistry of C, N, and P in a Soil Catena of the Shortgrass Steppe , 1985 .

[11]  N. Fetcher,et al.  Changes in Arctic Tussock Tundra Thirteen Years after Fire , 1984 .

[12]  S. W. Roberts,et al.  Plant-soil processes in eriophorum vaginatum tussock tundra in alaska: a systems modeling approach , 1984 .

[13]  P. Miller.  Environmental and vegetational variation across a snow accumulation area in montane tundra in central Alaska , 1982 .

[14]  P. Miller,et al.  Seasonal dynamics and standing crops of biomass and nutrients in a subarctic tundra vegetation , 1982 .

[15]  L. Tieszen,et al.  Vegetation and Production Ecology of an Alaskan Arctic Tundra , 1980, Ecological Studies.

[16]  F. S. Chapin,et al.  Response to fertilization by various plant growth forms in an Alaskan tundra: nutrient accumulation and growth , 1980 .

[17]  G. Shaver,et al.  THE VERTICAL DISTRIBUTION OF LIVE VASCULAR PHYTOMASS IN COTTONGRASS TUSSOCK TUNDRA , 1979 .

[18]  R. Haag,et al.  Energy Budget Changes Following Surface Disturbance to Upland Tundra , 1974 .

[19]  R. Wein,et al.  Changes in Arctic Eriophorum Tussock Communities Following Fire , 1973 .

[20]  Harold A. Mooney,et al.  THE ECOLOGY OF ARCTIC AND ALPINE PLANTS , 1968 .

[21]  A. Christiansen,et al.  Arctic National Wildlife Refuge, Alaska, coastal plain resource assessment : report and recommendation to the Congress of the United States and final legislative environmental impact statement , 1987 .

[22]  Leslie A. Viereck,et al.  Taiga Ecosystems in Interior Alaska , 1983 .

[23]  P. Webber.  Spatial and Temporal Variation of the Vegetation and Its Production, Barrow, Alaska , 1978 .

[24]  J. R. Rastorfer.  Composition and Bryomass of the Moss Layers of Two Wet-Tundra-Meadow Communities Near Barrow, Alaska , 1978 .

[25]  R. Wein,et al.  Primary Production in Arctic Cottongrass Tussock Tundra Communities , 1974 .

[26]  R. Haag.  Nutrient limitations to plant production in two tundra communities , 1974 .