Agricultural activities and the global carbon cycle

Publication Type:

Journal Article

Authors:

R. Lal

Source:

Nutrient Cycling in Agroecosystems, Volume 70, p.103-116 (2004)

URL:

http://dx.doi.org/10.1023/B:FRES.0000048480.24274.0f

Keywords:

Conservation tillage, Soil carbon sequestration, Soil organic matter dynamics, Soil quality, Terrestrial carbon pool

Abstract:

The observed and projected increase in emission of greenhouse gases, with attendant effects on global warming and sea level rise, have raised interests in identifying mitigation options. Terrestrial C sequestration involves capture of atmospheric C through photosynthesis and storage in biota, soil and wetlands. Land use, vegetation and soil management have a strong impact on the biotic processes of C sequestration. Losses of C from the terrestrial ecosystems are exacerbated by deforestation, biomass burning, plowing, resource-based and subsistence agriculture, and practices that mine soil fertility and deplete the soil organic C (SOC) pool. Biomass burning may also produce charcoal, which is an inert carbon with long residence time. Practices that enhance C sequestration include afforestation and reforestation, conservation tillage and mulch farming, integrated nutrient management and adopting systems with high biodiversity. Net C sequestration within an ecosystem can be assessed by taking into account the hidden C costs of fertilizers, pesticides, tillage, irrigation and other input. Restoration of degraded soils and ecosystems has a vast potential of C sequestration. The Kyoto Protocol provides for C sequestration in terrestrial sinks and C trading through Clean Development Mechanisms. Terrestrial C sequestration, besides being a win

Notes:

<p>[1]doi:10.1023/B:FRES.0000048480.24274.0f</p>