Organic carbon sequestration under chaparral and pine after four decades of soil development

摘要: Abstract Soils are the largest carbon reservoir of terrestrial ecosystems, and play a central role in global cycle. The large lysimeter installation at San Dimas Experimental Forest southern California allowed quantification storage biosequence soils under chamise (Adenostoma fasciculatum Hook. Am.), hoaryleaf ceanothus (Ceanothus crassifolius Torr.), scrub oak (Quercus dumosa Nutt.), Coulter pine (Pinus coulteri B. Don). After four decades soil development, sequestration lysimeters ranged from 4552 to 17,561 g m−2. Carbon accretion mineral (0–1 m) chaparral represented larger percentage total above-ground biomass (23–27%) as compared (13%). Also, contribution A horizon whole OC was higher than pine. surface horizons related earthworm activity, which intense oak, but absent sampled 1987 corresponding archived fill materials were fractionated according density particle size fractions, analyzed for N by dry combustion. nitrogen concentrations all fractions can be ranked highest lowest plant species: > Under chaparral, greater proportion recovered sand fraction C ratio this sand-sized organic matter This is indicative fresh residues that may not contribute long-term soils.