Soil Temperature, Water Content, and Barley Development of Level vs. Ridged Subarctic Seedbeds
1996
Sharratt, B. S.
Ridge tillage may promote early-season warming of soils in subarctic regions and thereby optimize the plant growing environment. This study was conducted to assess soil temperature and water content, along with barley (Hordeum vulgare L.) development, on a level vs. ridged Pergelic Cryaquept at Fairbanks, AK. Ridges were oriented north-south, east-west, northeast-southwest, and northwest-southeast. Seed zone soil temperature and water content were measured, the former by thermocouples, at the ridge peak and furrow as well as on ridge slopes where barley was grown during the 1989 through 1991 growing seasons. Barley grown on the level surface and on southerly ridge aspects produced at least 25 g m⁻¹ more grain and 20 g m⁻¹ more straw than barley grown on northerly aspects. The vegetative developmental rate was 0.03 leaves d⁻¹ faster on southern ridge aspects or the level surface than on northern aspects, owing to 2°C higher temperatures of soil with a southerly or level exposure. Soil water content on northern ridge aspects was occasionally 0.05 m³ m⁻³ higher than on southern aspects in the early growing season (<60 d after planting), but 0.04 m³ m⁻³ lower than on the level soil surface in the late growing season (>60 d after planting). In the subarctic, the plant growing environment is as favorable on a level soil surface as on a south-facing ridge aspect, owing to nearly equal early-season soil temperatures and higher soil water content in the late season.
显示更多 [+] 显示较少 [-]