Ecosystem carbon stocks and distribution under different land-uses in north central Alberta, Canada

• Published in: Forest ecology and management Vol. 257; no. 8; pp. 1776 - 1785
• Main Authors: Arevalo, Carmela B.M., Bhatti, Jagtar S., Chang, Scott X., Sidders, Derek
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 31.03.2009; [Amsterdam]: Elsevier Science; Elsevier
• Subjects: 13C and 15N natural abundance; agricultural land; Animal and plant ecology; Animal, plant and microbial ecology; Artificial regeneration. Forest nurseries. Planting; Biological and medical sciences; carbon; Carbon sequestration; forest plantations; Forestry; forests; Fundamental and applied biological sciences. Psychology; grasslands; Hybrid poplars; hybrids; land use; land use change; Linaria; particle size; particle size distribution; Particle-size fractions; Populus; Populus tremuloides; roots; soil; soil organic carbon; soil properties; soil texture; Sowing and planting; stems; Synecology; Terrestrial ecosystems; Tree plantations; trees; vegetation cover; Canada; Alberta; North America; America; Canada, Alberta; Tree plantations; Populus; Hybrid poplars; Particle-size fractions; Carbon sequestration; 13C and 15N natural abundance; Carbon Isotopes; Isotopic composition; Nitrogen Isotopes; Dicotyledones; Ecosystem; Angiospermae; Tree; Nitrogen-15; Vegetals; Forest ecology; Hybrid; Woody plant; Land use; Salicaceae; Particle size distribution; C-13; Artificial forest stand; Forestry; Spermatophyta; Stock
• ISSN: 0378-1127; 1872-7042
• DOI: 10.1016/j.foreco.2009.01.034

Land-use and land cover strongly influence carbon (C) storage and distribution within ecosystems. We studied the effects of land-use on: (i) above- and belowground biomass C, (ii) soil organic C (SOC) in bulk soil, coarse- (250–2000 μm), medium- (53–250 μm) and fine-size fractions (<53 μm), and (iii) 13C and 15N abundance in plant litter, bulk soil, coarse-, and medium- and fine-size fractions in the 0–50 cm soil layer in Linaria AB, Canada between May and October of 2006. Five adjacent land-uses were sampled: (i) agriculture since 1930s, (ii) 2-year-old hybrid poplar ( Populus deltoides × Populus × petrowskyana var. Walker) plantation, (iii) 9-year-old Walker hybrid poplar plantation, (iv) grassland since 1997, and (v) an 80-year-old native aspen ( Populus tremuloides Michx.) stand. Total ecosystem C stock in the native aspen stand (223 Mg C ha −1) was similar to that of the 9-year-old hybrid poplar plantation (174 Mg C ha −1) but was significantly greater than in the agriculture (132 Mg C ha −1), 2-year-old hybrid poplar plantation (110 Mg C ha −1), and grassland (121 Mg C ha −1). Differences in ecosystem C stocks between the land-uses were primarily the result of different plant biomass as SOC in the 0–50 cm soil layer was unaffected by land-use change. The general trend for C stocks in soil particle-size fractions decreased in the order of: fine > medium > coarse for all land-uses, except in the native aspen stand where C was uniformly distributed among soil particle-size fractions. The C stock in the coarse-size fraction was most affected by land-use change whilst the fine fractions the least. Enrichment of the natural abundances of 13C and 15N across the land-uses since time of disturbance, i.e., from agriculture to 2- and then 9-year-old hybrid poplar plantations or to grassland, suggests shifts from more labile forms of C to more humified forms of C following those land-use changes.