Publications of Ramin Heidarian Dehkordi
Bookmark and Share    
Full Text
See detailUsing UAV Collected RGB and Multispectral Images to Evaluate Winter Wheat Performance Across a Site Characterized by Century-Old Biochar Patches in Belgium
Heidarian Dehkordi, Ramin ULiege; Burgeon, Victor ULiege; Fouche, Julien et al

in Remote sensing (2020), 12

Remote sensing data play a crucial role in monitoring crop dynamics in the context of precision agriculture by characterizing the spatial and temporal variability of crop traits. At present there is ... [more ▼]

Remote sensing data play a crucial role in monitoring crop dynamics in the context of precision agriculture by characterizing the spatial and temporal variability of crop traits. At present there is special interest in assessing the long-term impacts of biochar in agro-ecosystems. Despite the growing body of literature on monitoring the potential biochar effects on harvested crop yield and aboveground productivity, studies focusing on the detailed crop performance as a consequence of long-term biochar enrichment are still lacking. The primary objective of this research was to evaluate crop performance based on high-resolution unmanned aerial vehicle (UAV) imagery considering both crop growth and health through RGB and multispectral analysis, respectively. More specifically, this approach allowed monitoring of century-old biochar impacts on winter wheat crop performance. Seven Red-Green-Blue (RGB) and six multispectral flights were executed over 11 century-old biochar patches of a cultivated field. UAV-based RGB imagery exhibited a significant positive impact of century-old biochar on the evolution of winter wheat canopy cover (p-value = 0.00007). Multispectral optimized soil adjusted vegetation index indicated a better crop development over the century-old biochar plots at the beginning of the season (p-values < 0.01), while there was no impact towards the end of the season. Plant height, derived from the RGB imagery, was slightly higher for century-old biochar plots. Crop health maps were computed based on principal component analysis and k-means clustering. To our knowledge, this is the first attempt to quantify century-old biochar effects on crop performance during the entire growing period using remotely sensed data. Ground-based measurements illustrated a significant positive impact of century-old biochar on crop growth stages (p-value of 0.01265), whereas the harvested crop yield was not affected. Multispectral simplified canopy chlorophyll content index and normalized difference red edge index were found to be good linear estimators of harvested crop yield (p-value(Kendall) of 0.001 and 0.0008, respectively). The present research highlights that other factors (e.g., inherent pedological variations) are of higher importance than the presence of century-old biochar in determining crop health and yield variability. [less ▲]

Detailed reference viewed: 80 (15 ULiège)
Full Text
See detailRemotely-sensed assessment of the impact of century-old biochar on chicory crop growth using high-resolution UAV-based imagery
Heidarian Dehkordi, Ramin ULiege; Denis, Antoine ULiege; Fouche, Julien et al

in International Journal of Applied Earth Observation and Geoinformation (2020), 91(September 2020),

In recent years, special attention has been given to the long-term effects of biochar on the performance of agro-ecosystems owing to its potential for improving soil fertility, harvested crop yields, and ... [more ▼]

In recent years, special attention has been given to the long-term effects of biochar on the performance of agro-ecosystems owing to its potential for improving soil fertility, harvested crop yields, and aboveground biomassproduction. The present experiment was set up to identify the effects on soil-plant systems of biochar producedmore than 150 years ago in charcoal mound kiln sites in Wallonia (Belgium). Although the impacts of biochar onsoil-plant systems are being increasingly discussed, a detailed monitoring of the crop dynamics throughout thegrowing season has not yet been well addressed. At present there is considerable interest in applying remotesensing for crop growth monitoring in order to improve sustainable agricultural practices. However, studiesusing high-resolution remote sensing data to focus on century-old biochar effects are not yet available. For thefirst time, the impacts of century-old biochar on crop growth were investigated at canopy level using high-resolution airborne remote sensing data over a cultivatedfield. High-resolution RGB, multispectral and thermalsensors mounted on unmanned aerial vehicles (UAVs) were used to generate high frequency remote sensinginformation on the crop dynamics. UAVs wereflown over 11 century-old charcoal-enriched soil patches and theadjacent reference soils of a chicoryfield. We retrieved crucial crop parameters such as canopy cover, vegetationindices and crop water stress from the UAV imageries. In addition, our study also providesin-situmeasurementsof soil properties and crop traits. Both UAV-based RGB imagery andin-situmeasurements demonstrated that thepresence of century-old biochar significantly improved chicory canopy cover, with greater leaf lengths in biocharpatches. Weighted difference vegetation index imagery showed a negative influence of biochar presence on plantgreenness at the end of the growing season. Chicory crop stress was significantly increased by biochar presence,whereas the harvested crop yield was not affected. The main significant variations observed between referenceand century-old biochar patches usingin situmeasurements of crop traits concerned leaf length. Hence, theoutput from the present study will be of great interest to help developing climate-smart agriculture practicesallowing for adaptation and mitigation to climate. [less ▲]

Detailed reference viewed: 48 (5 ULiège)
See detailLes drones Un nouvel eldorado pour les scientifiques et les entrepreneurs?
Heidarian Dehkordi, Ramin ULiege; Denis, Antoine ULiege

Scientific conference (2018, December 13)

Detailed reference viewed: 52 (6 ULiège)