ITC PhD Publication Award 2024 Celebrating Excellence in Research

Peiyu Lai's study, titled "Characterizing Crop Productivity under Heat Stress Using MODIS Data," developed a method to identify heat stress in crops using remote sensing. By analyzing multispectral data and vegetation indices, the research demonstrated that heat stress increases red band reflectance, which can be effectively detected. The study utilized MODIS data over 78 periods of heat stress to assess the sensitivity of canopy reflectance and its impact on Gross Primary Production. Key indices showed high accuracy in distinguishing stressed crops, aiding in better crop modeling and climate change studies. Peiyu plans to incorporate this spectral signal into the light-use efficiency model to improve crop productivity estimation under heat stress, contributing to food security in a warming future.

I am honored to receive this award and deeply grateful to the ITC faculty and my supervisors, Michael, Roshanak, and Andy, for their invaluable support. This recognition strengthens my confidence to continue my research enthusiastically.

The most innovative aspect of this paper is our approach to identifying crop heat stress independently of confounding factors like low soil moisture or unfavorable light conditions. This allows us to pinpoint the unique spectral signal from remote sensing and monitor the impact of heat stress on agricultural productivity.

The jury praised the method's innovation in isolating heat stress and capturing it with MODIS-derived indices. The research was thorough, covering a wide range of global situations and evaluating all assumptions. The work's societal importance lies in its global applicability and direct address of food security in a changing climate. The article was well-written and accessible to readers outside the immediate scientific field. Prof Dr Martin van Maarseveen awarded the cheque to mrs. Peiyu Lai on behalf of the jury.

Reference: Lai, Peiyu, Marshall, Michael, Darvish, Roshanak, Tu, Kevin, Nelson, Andrew, 2024. Characterizing crop productivity under heat stress using MODIS data. In: Agricultural and Forest Meteorology, volume 355, August 2024, 110116. https://doi.org/10.1016/j.agrformet.2024.110116

Keke Duan's article, "Detection and Attribution of Cereal Yield Losses Using Sentinel-2 and Weather Data: A Case Study in South Australia," presents a method to predict in-season crop yield losses due to weather extremes at the sub-field level using remote sensing. The study demonstrated the method's effectiveness through a case study in South Australia (2017-2022). By aligning EVI-2 time series with thermal time, researchers created a Crop Damage Index (CDI) to detect growth anomalies and predict yield loss. The method showed high accuracy, predicting yield reduction before grain-filling with R² values of 0.83 for wheat and 0.91 for barley.

This study presents a scalable framework for crop damage assessment by integrating high-resolution satellite time series with weather data. It demonstrates the potential for near real-time monitoring of crop yield losses and their accurate attribution to weather extremes.

I am currently refining the system for more robust monitoring of crop response to external stresses. The focus is incorporating accurate crop phenology retrieval as it informs growth stage dynamics and sensitivities, enabling targeted assessment and mitigation strategies.

The jury found the CDI framework novel and effective for early-season crop yield estimation based on weather stress. The article was rigorous, with detailed explanations and a solid conceptual overview. The work's societal relevance is significant, addressing food security and climate change. Prof Dr Martin van Maarseveen congratulated mrs. Keke Duan on behalf of the jury. 

Reference: Duan, Keke, Vrieling, Anton, Schlund, Michael, Bhaskar Nidumolu, Uday, Ratcliff, Christina, Collings, Simon, Nelson, Andrew, 2024. Detection and attribution of cereal yield losses using Sentinel-2 and weather data: A case study in South Australia. In: ISPRS Journal of Photogrammetry and Remote Sensing, Volume 213, July 2024, pages 33-52. https://doi.org/10.1016/j.isprsjprs.2024.05.021

The ITC PhD Publication Award is an annual recognition for PhD candidates who are the first authors of outstanding scientific publications. The prize includes an award certificate and €1000. A jury of professors and a PhD candidate evaluate the publications based on presentation, innovation, scientific rigor, practical/scientific relevance, and readability.