Premium
Leaf Area Dynamics of a Shortgrass Prairie in Colorado
Author(s) -
Knight Dennis H.
Publication year - 1973
Publication title -
ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.144
H-Index - 294
eISSN - 1939-9170
pISSN - 0012-9658
DOI - 10.2307/1935685
Subject(s) - leaf area index , quadrat , irrigation , grassland , growing season , environmental science , specific leaf area , grazing , agronomy , productivity , human fertilization , biology , ecology , botany , photosynthesis , shrub , macroeconomics , economics
Leaf area changes were studied at the Prawnee Grassland in northern Colorado. Specific objectives were (1) to measure seasonal changes in leaf area during 1970 and 1971, (2) to estimate the influence of irrigation, irrigation plus nitrogen fertilization, and grazing on leaf area, and (3) to calculate average daily above—ground productivity per unit of leaf area during the peak of the growing season. The point—quadrat method was used for leaf area measurement. Peak leaf area was reached in mid—June of both years, with a maximum Leaf Area Index of 0.55 in 1970. Both years were drier than average, but seasonal distribution of rainfall was different with a corresponding seasonal difference in LAI. Irrigation alone increased LAI about two—thirds, and irrigation plus fertilization increased LAI approximately tenfold. Different grazing treatments had little effect on total leaf area values. Above—ground productivity per unit leaf area averaged about 5 g/day/l 2 of leaf area in May and about 4 g in June and July 1970.