In-situ crop phenology dataset from sites in Bulgaria and France

Site description The in-situ crop phenology stages dataset was collected from Bulgarian and French sites for major European crops. Each selected field is described by its precise location and shape. In Bulgaria, seventeen production crop fields were selected: Oborishte (P0 and P3), Gurkovo (P01 and P13), Trigorci (P02), General Kiselovo (P1 and P2), Dobrich (P4 and P18), Mirovci (P14), Neofit Rilski (P15), Boyana (P17) and Gurkovo (P19, P20, P22, P23, P24) in the Northeast part of the Danube plain. Winter rapeseed and wheat were grown in the selected sites. The cultivation follows a crop rotation schema, but the collected in-situ phenology data was from one growing season only per field. The sites are characterized by mostly flat terrain and a moderate continental climate with cold winters and hot summers. The annual cumulative precipitation is 540 mm, and the mean annual temperature is 10.2˚C. The soil has mainly a sandy loam texture. In France, two research fields were selected: Lamasquère (FR-Aur) and Auradé (FR-Lam). The FR-Aur crop site is part of a grain farm located in a hilly area where winter wheat – rapeseed – barley – sunflower crop rotation is used. The FR-Lam site is located in a plain where a winter wheat – irrigated maize crop rotation is practiced. Winter cover crops (Faba bean, white mustard) were sometimes introduced on both sites between a winter crop and a summer crop. During the selected time frame all mentioned crop species were cultivated. The climate is temperate with Mediterranean and oceanic influences, with mild winters, rainy springs, and high temperatures over the summer with low rainfall, followed by sunny autumns. The mean annual rainfall over the past 24 years was 617 ± 101 mm and the mean annual temperature was 13.7 ± 0.6 °C on both sites (Beziat et al. 2009, Tallec et al. 2022). According to the textural triangle of Malterre and Alabert (1963), the soil of the FR-Lam site has mainly clay, silt, and sand and FR-Aur is silt, clay, and sand. Crop phenology measurements The Start of the Season (SOS) is represented by a specific phenophase that corresponds to the BBCH10-13 distinguishable phenology stage and the End of the Season (EOS) by the Harvest date. In Bulgaria, crop data (Sowing, Phenophase, and Harvest date) from all fields were collected by visual observations in the field, written in a paper notebook, and subsequently passed to a Microsoft Excel file. The available data for each field is one season and some fields don't have the corresponding phenophase or harvest date. In France, crop data (Sowing and Harvest date) from both fields were collected through visual observation on site, identical to the Bulgaria sites. The phenophase date was determined by visual observations on site and/or PhenoCam picture and/or classical photo camera picture analysis. The unique exception is the Lamasquére site in the 2017/2018 and 2019/2020 seasons where the phenophase date was collected through visual observations on site. The available data for both fields have numerous crop seasons. File description The file “1_senseco_data_insitu_crop_phenology_Bulgaria_France.txt” concerns all crop phenology measurements (Sowing, Harvest, and Phenophase date) and related information, “2_senseco_metadata_insitu_crop_phenology_Bulgaria_France.txt” describes all the variables from “1_senseco_data_insitu_crop_phenology_Bulgaria_France.txt”. All 'jpg' files are photos from French sites. All 'geojson' georeferenced shape files are from each crop plot and the 'csv' files are the georeferenced shape files in an open format. Bibliography Beziat, P., Ceschia, E., Dedieu, G., 2009. Carbon balance of a three crop succession over two cropland sites in South West France. Agricultural and Forest Meteorology 149, 1628–1645. https://doi.org/10.1016/j.agrformet.2009.05.004 Malterre, H. and Alabert, M. : Nouvelles observations au sujet d’un mode rationnel de classement des textures des sols et des roches meubles - pratique de l’interprétation des analyses physiques, Bulletin de l’AFES 2, 76-84, 1963. Tallec, T., Bigaignon, L., Delon, C., Brut, A., Ceschia, E., Mordelet, P., Zawilski, B., Granouillac, F., Claverie, N., Fieuzal, R., Lemaire, B., Le Dantec, V., 2022. Dynamics of nitrous oxide emissions from two cropping systems in southwestern France over 5 years: Cross impact analysis of heterogeneous agricultural practices and local climate variability. Agricultural and Forest Meteorology 323, 109093. https://doi.org/10.1016/j.agrformet.2022.109093 Acknowledgment This research was supported by the Action CA17134 SENSECO (Optical synergies for spatiotemporal sensing of scalable ecophysiological traits) funded by COST (European Cooperation in Science and Technology, www.cost.eu, accessed on March 17, 2023).