Abstract
Availability of georeferenced yield data involving different crops over years, and their use in future crop management, are a subject of growing debate. In a 9 hectare field in Northern Italy, seven years of yield data, including wheat (3 years), maize for biomass (2 years), sunflower, and sorghum, and comprising remote (Landsat) normalized difference vegetation index (NDVI) data during central crop stages, and soil analysis (grid sampling), were subjected to geostatistical analysis (semi-variogram fitting), spatial mapping (simple kriging), and Pearson’s correlation of interpolated data at the same resolution (30 m) as actual NDVI values. Management Zone Analyst software indicated two management zones as the optimum zone number in multiple (7 years) standardized yield data. Three soil traits (clay content, total limestone, total nitrogen) and five dates within the NDVI dataset (acquired in different years) were shown to be best correlated with multiple- and single-year yield data, respectively. These eight parameters were normalized and combined into a two-zone multiple soil and NDVI map to be compared with the two-zone multiple yield map. This resulted in 83% pixel agreement in the high and low zone (89 and 10 respective pixels in the soil and NDVI map; 73 and 26 respective pixels in the yield map) between the two maps. The good agreement, which is due to data buffering across different years and crop types, is a good premise for differential management of the soil- and NDVI-based two zones in future cropping seasons.
Highlights
Field management zones in precision agriculture (PA) are defined as “the sub-regions within the same piece of land showing similar yield influencing factors within which different crop management practices are carried out at the right time and place to optimize crop productivity and minimize adverse environmental impact” [1]
Thereafter, we developed two-zone maps based on each of the eight soil traits and normalized difference vegetation index (NDVI) data, using the Management Zone Analyst (MZA) clustering method
Arable crop fields subjected for a number of years to georeferenced yield mapping obtain an amount of data deserving to be exploited in future crop management
Summary
Field management zones in precision agriculture (PA) are defined as “the sub-regions within the same piece of land showing similar yield influencing factors within which different crop management practices are carried out at the right time and place to optimize crop productivity and minimize adverse environmental impact” [1]. Well delineated homogenous areas should have the same yield trend across years and different cultivated crops [2]. These management zones are used for site-specific, real-time crop management, and for soil sampling to characterize the soil nutrient levels for variable rate fertilization [3]. It is recognized that there is often high spatial variability within the same field, due to nutrients or other factors or interaction among them, which influence the final crop yield. Efficient methods should be used to measure the within-field spatial variability in an appropriate way for delineating site-specific zones [9]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
