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Woody Vegetation Of A Disjunct Oak Woodland In East-Central Nebraska., Debra Ann Beightol
Woody Vegetation Of A Disjunct Oak Woodland In East-Central Nebraska., Debra Ann Beightol
Student Work
The woody vegetative composition of the Oak Glen Wildlife Management Area, a disjunct oak woodland in Seward County, Nebraska, was assessed using the Point-Quarter method. Based on data from three size categories, the presettlement composition of the woodland appears to have been a bur oak (Quercus macrocarpa) dominated community which, based on spacing and growth form, may have been savanna-like. Under present management, this community is succeeding to one consisting primarily of elm (Ulmus spp.), and hackberry (Celtis occidentalis)
An Investigation Of The Chlorophylls Of Selected Prasinophyte Algae., Leslie Carlat Kwasnieski
An Investigation Of The Chlorophylls Of Selected Prasinophyte Algae., Leslie Carlat Kwasnieski
Student Work
Introduction: Chlorophyll a is the prevalent light-collecting pigment in eukaryotic, photosynthetic organisms. Several different chlorophylls exist in nature, but all autotrophic plants contain chlorophyll a (Bogorad, 1976). The majority of these chlorophyll a molecules function to absorb light and channel the excitation energy to photochemical sites in reaction centers. Chlorophylls b, c, d, and e, carotenoid pigments and phycobiliproteins are organized into antenna systems which absorb light maximally at different wavelengths. This design permits the visible light spectrum to be exploited (Foyer, 1984) for energy by different photosynthetic organisms. Chlorophyll b is present in higher plants, Chlorophyta, Prasinophyceae, and Euglenophyta; …
Recent Ponderosa Pine (Pinus Ponderosa) Occurrence In Nebraska Sandhills Prairie., Ernest M. Steinauer
Recent Ponderosa Pine (Pinus Ponderosa) Occurrence In Nebraska Sandhills Prairie., Ernest M. Steinauer
Student Work
Four stands of ponderosa pine (Pinus ponderosa), situated within sandhills prairie sites in north central Nebraska, were evaluated for age distribution, reproductive status and spatial distribution. Trees were generally young; of the 563 individuals sampled, 11 had establishment dates prior to 1900 with the oldest dated 1868. All trees greater than 55 years old bore cones. Initial tree establishment appears to have occurred on north facing slopes where both the oldest trees and 92% of all trees observed were located. Age structure data show pine populations are increasing in all four prairie sites. This study shows that, under present management, …