Dr Alexandra Crème1,2, Dr Cornelia Rumpel3, Dr Nicolas Sarby4, Prof Sparkle Malone5, Dr Francois Gastal6, M Xavier Charrier6, Dr Abad Chabbi1,2
1Ecosys, INRA, Thiverval-Grignon, France, 2P3F, INRA, Lusignan, France, 3IEES, CNRS, Thiverval-Grignon, France, 4Infosol, INRA, Orléans, France, 5Florida International University, Miami, USA, 6UE Ferlus, INRA, Lusignan, France
Management practices determining the impact of temporary grassland on soil organic matter (SOC) include duration, fertilization, and grazing strategies or mowing regime. Increasing grassland duration appears to be the most important management practice to enhance SOC sequestration. Up to now impact of grassland management on SOC stock changes were mostly studied after replicated field sampling without taking into account spatial heterogeneity of soil at the plot scale and field scale. In the present study we used geostatistical sampling and satellite imaging to evaluate SOC loss and gain 9 years after introduction of different grassland management practices on temperate loamy soils in Western France. The soils had been under continuous crop, permanent and temporary grasslands with contrasting management in terms of fertilization, duration and harvesting (grazing or mowing). In the present study, we evaluated the impact of introduction of permanent or temporary grasslands with contrasting management on the spatial distribution of SOC storage on a decadal timescale.
Overall, after nine years of treatment, SOC increases were noted under permanent grassland, while permanent cropping reduced SOC stocks and the introduction of temporary grassland maintained SOC, except for grazed temporary grassland, which was characterized by carbon loss. SOC stock changes determined by the ground-based geostatistical approach showed treatment effects at 0.4 ha field plots. At larger scale (3ha) plots, SOC changes were variable and zones with SOC gain and loss were found under the same treatment. These differences could to some extent be explained by changes in physicochemical soil parameters. Ground based SOC stock changes showed a correlation with satellite based vegetation data (NDVI). We conclude, that evaluation of SOC stock changes at multiple scales is necessary to infer management effects on SOC. Moreover, remote sensing of vegetation may be a promising avenue to evaluate belowground SOC changes due to management.
Cornelia Rumpel is a research director working for the French National Research Center (CNRS) at the Institute of Ecology and Environmental Sciences Paris. She studied forestry in Germany and Scotland and received a master diploma from the Ludwig-Maximilans University at Munich, Germany in 1994. Afterwards, she worked as a research scientist at the Brandenbourg University of Technology in Cottbus, Germany, where she obtained her PhD degree in natural sciences in 1999. she studied the origin and fate of terrestrial organic matter, aiming to understand the mechanisms controlling carbon sequestration in soils. Her studies concerned various spatial and temporal scales in different environments ranging from soils and sediments in mining areas to natural as well as managed ecosystems, including those affected by fire. Her work was carried out in temperate and tropical climates and the results of her research changed of a number of paradigms. She published >160 papers, which were cited more than 8000 times. In 2016 and 2017 she was listed as a highly cited researcher. She was nominated ambassador of the Technical University of Munich and has been the chair of the STC of the 4p1000 initiative since 2018.