Ecological investigations of the tundra biome in the Prudhoe Bay region, Alaska ecologicalinvest00brow Year: 1975 Soil thaw In 1972 Bilgin (1975) measured the progres- sion of soil thaw at 14 different sites. Soils varied in texture, organic content, moisture, slope and resulting vegetative cover. The range in maximum soil thaw by late August was between 25 cm in wet organic soil and 90 cm in the dry sandy upland soils. Fig. 3 contains plots of thaw progression in four distinct soil conditions. This range in soil thaw over relatively small distances is common for northern Alaska and has been
Ecological investigations of the tundra biome in the Prudhoe Bay region, Alaska ecologicalinvest00brow Year: 1975 Soil thaw In 1972 Bilgin (1975) measured the progres- sion of soil thaw at 14 different sites. Soils varied in texture, organic content, moisture, slope and resulting vegetative cover. The range in maximum soil thaw by late August was between 25 cm in wet organic soil and 90 cm in the dry sandy upland soils. Fig. 3 contains plots of thaw progression in four distinct soil conditions. This range in soil thaw over relatively small distances is common for northern Alaska and has been reported for a detailed transect in the Barrow area (Brown 1969). Table 6 Comparison of 1971 precipitation data (mm) June (13-30 June) July August September trace Barrow Barter Island Prudhoe Bay (near Pingo Site) Happy Valley * *\/alue wholly or partially estimated. Soil Temperature Soil temperatures as influenced by polygon microrelief were recorded at six locations at 3-hr intervals during summer 1972. The sites were located within a 15-m radius with duplicate sites selected in a polygon trough, on a polygon rim, and in a polygon center. Fig. 4 is an idealized cross-section and plan view of the site. Fig. 5 contains the daily mean values for each of the three microrelief positions at 1, 5, and 10 cm depths and the Prudhoe air tempera- ture record. The July and August 1972 mean daily tem- peratures in the upper 1 to 10 cm soil were Sandy Upland Tundra 80 60 3 D o 40 a. Q 20 0 Sandy Dry Meadow Tundra Silty Dry Meadow Tundra Dry Phase Organic Soil 20 Jun 10 20 Jul 10 20 Aug 1972 Fig. 3. Seasonal progression of thaw for four Prudtioe Bay soils (Bilgin 1975). m
Size: 1110px × 1802px
Photo credit: © Bookend / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: archive, book, drawing, historical, history, illustration, image, page, picture, print, reference, vintage
