@article{fdi:010061278,
  title = {{A}ssessing soil carbon storage rates under no-tillage : comparing the synchronic and diachronic approaches},
  author = {{C}osta, {C}. and {C}orbeels, {M}. and {B}ernoux, {M}artial and {P}iccolo, {M}. {C}. and {N}eto, {M}. {S}. and {F}eigl, {B}. {J}. and {C}erri, {C}. {E}. {P}. and {C}erri, {C}. {C}. and {S}copel, {E}. and {L}al, {R}.},
  editor = {},
  language = {{ENG}},
  abstract = {{N}o-tillage ({NT}) practices with crop residue mulching are seen as an effective way to accumulate soil carbon ({C}). {T}he rate of soil {C} accumulation can be determined by measuring soil {C} stocks over time (diachronic approach) or along a chronosequence that substitutes spatial history differences for time differences (synchronic approach). {T}he objective of this communication is to compare the diachronic and synchronic approaches for determining the rates of soil {C} storage under {NT} in the {C}errado region of {B}razil. {I}n 2003 and 2007, soil {C} stocks (0-20 cm) were determined in three {NT} fields with 5, 9 and 17 years of {NT} adoption in 2007 ({NT}-5, {NT}-9 and {NT}-17, respectively), one conventionally tilled field ({CT}, 30 years of tillage in 2007) and one native {C}errado plot ({CE}) in {R}io {V}erde ({G}oias state, {B}razil). {S}oil {C} accumulation rates were calculated following both the synchronic and diachronic approach. {R}esults from the synchronic approach showed that 30 years of cropping under {CT} depleted the soil {C} stock to 34.4 {M}g {C} ha(-1), which is a decrease of about 27% of the original levels observed under the native vegetation ({CE}, 47.1 and 47.3 {M}g {C} ha(-1), respectively, in 2003 and 2007). {I}nstead, {NT} adoption had been accumulating soil {C} through the evaluated years. {S}oil {C} stocks measured under {NT} areas in 2003 and 2007 were 29.9 and 31.3 {M}g {C} ha(-1) ({NT}-5), 33.4 and 34.4 {M}g {C} ha(-1) ({NT}-9) and 45.8 and 46.4 {M}g {C} ha(-1) ({NT}-17), respectively. {M}uch more moderate rates of soil {C} accumulation were observed diachronically (0.12-0.28 {M}g {C} ha(-1) year(-1)) than with the synchronic approach (133 and 1.27 {M}g {C} ha(-1) year(-1) in 2003 and 2007, respectively). {S}oil {C} stocks under {CE} between 2003 and 2007 (in the diachronic approach) did not change, indicating that diachronic measurements were accurate. {T}hus, it appears to be very difficult to eliminate all non-wanted sources of soil {C} variation (i.e. soil texture, land-use history) analysing the soil {C} accumulation in a chronosequence (synchronic approach). {I}n spite of a time span of years between sampling dates, our results suggest the need for using the diachronic approach when assessing soil {C} changes under altering land-use or management patterns. {I}ncreasing the number of diachronic assessments may also help the parameterization of process-oriented models for exploring the effects of no-tillage systems on soil {C} storage rates more accurately.},
  keywords = {{C}errado ; {S}oil organic matter ; {S}oil {C} accumulation ; {N}o-tillage ; {S}oil sampling ; {BRESIL}},
  booktitle = {},
  journal = {{S}oil and {T}illage {R}esearch},
  volume = {134},
  numero = {},
  pages = {207--212},
  ISSN = {0167-1987},
  year = {2013},
  DOI = {10.1016/j.still.2013.08.010},
  URL = {https://www.documentation.ird.fr/hor/fdi:010061278},
}