Soil Carbon Accumulation and CO2 Flux in Experimental Restoration Plots, Southern Iceland: Comparing Soil Treatment Strategies

• Published in: Applied and Environmental Soil Science
• Main Authors: Lawrence H. Tanner, Morgan Nivison, Olafur Arnalds, Kristin Svavarsdóttir
• Format: Article in Journal/Newspaper
• Language: English
• Published: Hindawi Limited 2015
• Subjects: envir; geo; Iceland
• Online Access: https://doi.org/10.1155/2015/205846; https://doaj.org/article/9f28577b3c6d43d09b3dfbdf223cfafc

Experimental plots were established on severely eroded land surfaces in Iceland in 1999 to study the rates and limits of soil carbon sequestration during restoration and succession. The carbon content in the upper 10 cm of soils increased substantially during the initial eight years in all plots for which the treatments included both fertilizer and seeding with grasses, concomitant with the increase in vegetative cover. In the following five years, however, the soil carbon accumulation rates declined to negligible for most treatments and the carbon content in soils mainly remained relatively constant. We suggest that burial of vegetated surfaces by aeolian drift and nutrient limitation inhibited productivity and carbon sequestration in most plots. Only plots seeded with lupine demonstrated continued long-term soil carbon accumulation and soil CO2 flux rates significantly higher than background levels. This demonstrates that lupine was the sole treatment that resulted in vegetation capable of sustained growth independent of nutrient availability and resistant to disruption by aeolian processes.