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New maps on cropping intensity patterns in Europe

Understanding the intensity of cropping is important for identifying potentials to close yield and harvesting gaps, and thus to lessen pressure on further land conversions. A new paper by Stephan Estel, published in Environmental Research letters, shows new maps of cropping frequency, multi- vs. single cropping, fallow cycles, and actual time a field is under crops on MODIS image time series from 2000 to 2012 for all of Europe.

Mapping cropland-use intensity across Europe using MODIS NDVI time series

 

Stephan Estel | Tobias Kuemmerle Christian Levers Matthias Baumann | Patrick Hostert

 

Global agricultural production will likely need to increase in the future due to population growth, changing diets, and the rising importance of bioenergy. Intensifying already existing cropland is often considered more sustainable than converting more natural areas. Unfortunately, our understanding of cropping patterns and intensity is weak, especially at broad geographic scales.Wecharacterized and mapped cropping systems in Europe, a region containing diverse cropping systems, using four indicators: (a) cropping frequency (number of cropped years), (b) multi-cropping (number of harvests per year), (c) fallow cycles, and (d) crop duration ratio (actual time under crops) based on the MODIS Normalized Difference Vegetation Index (NDVI) time series from 2000 to 2012. Second, we used these cropping indicators and self-organizing maps to identify typical cropping systems. The resulting six clusters correspond well with other indicators of agricultural intensity (e.g., nitrogen input, yields) and reveal substantial differences in cropping intensity across Europe. Cropping intensity was highest in Germany, Poland, and the eastern European Black Earth regions, characterized by high cropping frequency, multi-cropping and a high crop duration ratio. Contrarily, we found lowest cropping intensity in eastern Europe outside the Black Earth region, characterized by longer fallow cycles. Our approach highlights how satellite image time series can help to characterize spatial patterns in cropping intensity—information that is rarely surveyed on the ground and commonly not included in agricultural statistics: our clustering approach also shows a way forward to reduce complexity when measuring multiple indicators. The four cropping indicators we used could become part of continental-scale agricultural monitoring in order to identify target regions for sustainable intensification, where trade-offs between intensification and the environmental should be explored.

 

Link to the manuscript: DOI:10.1088/1748-9326/11/2/024015

Citation: Estel, S., Kuemmerle, T., Levers, C. &Hostert, P. (2016): Mapping cropland-use intensity across Europe using MODIS NDVI time series. Environmental Research Letters, 11, 024015.