Affiliations: State Key Laboratory of Soil and Sustainable
Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing
210008, China | College of Geographical Sciences, Fujian Normal
University, Fuzhou 350007, China | College of Resourcesand Environment, Northwest
Sci-Tech University of Agriculture and Forestry, Yangling 712100, China
Abstract: Although numerous studies about the nature and turnover of soil
organic matter (SOM) in light and heavy fractions (LFOM and HFOM, respectively)
have been made, little information is available in relation to the relationship
between LFOM and HFOM, and no attempts have been made to quantify a general
relationship between LFOM and HFOM for agricultural soils under field
condition. Our hypothesis is there may be an inherent relationship between LFOM
and HFOM for agricultural soils under certain unaltered management practices
for a long period, to this end, we therefore studied typically soils taken from
different parts in China by using a simple density fractionation procedure. The
results indicated that LFOM was positively correlated with LFOM/HFOM ratio for
three typical soils. This information will be of particular use not only in
deepening our understanding of the dynamics of SOM fractions but also in
evaluating the potential of agricultural soils to sequestrate C under different
management practices in a long term.
Keywords: soil organic matter, light fraction, heavy fraction, agricultural soils
