Effect of repeated burning on plant and soil carbon and nitrogen in cheatgrass (Bromus tectorum) dominated ecosystems

• Published in: Plant and soil Vol. 386; no. 1-2; pp. 47 - 64
• Main Authors: Jones, Rachel, Chambers, Jeanne C, Johnson, Dale W, Blank, Robert R, Board, David I
• Format: Journal Article
• Language: English
• Published: Cham Springer-Verlag 01-01-2015; Springer; Springer International Publishing; Springer Nature B.V
• Subjects: Artemisia tridentata subsp. wyomingensis; Biogeochemistry; Biomedical and Life Sciences; Bromus tectorum; burning; carbon; Carbon content; cold; Combustion; Ecology; Ecosystems; Environmental aspects; Environmental factors; Forest & brush fires; Grasses; Life Sciences; Litter; multivariate analysis; Nitrogen; nitrogen content; Nonnative species; Plant Physiology; Plant Sciences; Plant-soil relationships; Regular Article; Seed banks; soil; Soil nutrients; Soil Science & Conservation; Soils; sowing; temperature; Terrestrial ecosystems; Vegetation; Shrublands; Cold desert; Sagebrush; Invasive annual grasses; Restoration; Repeated fire
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-014-2242-2

BACKGROUND AND AIMS: Fire has profound effects on ecosystem properties, but few studies have addressed the effect of repeated burns on soil nutrients, and none have been conducted in cold desert ecosystems where invasion by exotic annual grasses is resulting in greater fire frequency. METHODS: In a 5 year study, we examined effects of repeated burning, litter removal, and post-fire seeding on carbon (C) and nitrogen (N) contents in soils, litter, and vegetation in a cheatgrass-dominated Wyoming big sagebrush ecological type. We developed a multivariate model to identify potential mechanisms influencing treatment effects and examine the influence of environmental factors such as precipitation and temperature. RESULTS: We found that repeated burning had strong negative effects on litter C and N contents, but did not reduce soil nutrients or vegetation C and N contents, likely due to cool fire temperatures. There were few effects of litter removal or post-fire seeding. Instead, precipitation and temperature interacted with burning and had the strongest influences on soil N and vegetation C and N contents over time. CONCLUSIONS: Management strategies aimed at decreasing litter and seed banks and increasing competitive interactions may be more effective at reducing cheatgrass success than approaches for reducing soil nutrients.