JpGU-AGU Joint Meeting 2017

講演情報

[EE]Eveningポスター発表

セッション記号 A (大気水圏科学) » A-CG 大気水圏科学複合領域・一般

[A-CG46] [EE] 衛星による地球環境観測

2017年5月20日(土) 17:15 〜 18:30 ポスター会場 (国際展示場 7ホール)

[ACG46-P33] Using radar to measure vegetation water stress

*Tim vanEmmerik1Susan Steele-Dunne1Nick van de Giesen1 (1.Water Resources Section, Delft University of Technology, The Netherlands)

キーワード:vegetation, remote sensing, drought

Vegetation water stress significantly affects agricultural and tropical forest canopies. Water shortages in crops influence plant water dynamics, reduces primary production and might eventually lead to plant death. Tropical forests are essential part of global carbon and water cycle. Continuing drying of e.g. the Amazon rainforest might accelerate climate change through carbon losses and changing land surface energy balances.

In addition to ground measurements, various studies have reported observations of plant water stress using active microwave remote sensing. For example, statistical significant variations in radar backscatter were shown to coincide with the onset of water stress over West Africa [1]. Others were able to link radar backscatter time series over the Amazon to the heavy 2005 drought [2].

Additional in situ measurements in agricultural and tropical forest canopies allow further exploration of the full potential of water stress detection using radar. Novel ground measurements techniques have been used to detect and quantify the effects of water stress in various types of plant canopies [3,4], increasing the understanding of how hydrological and plant physiological signatures of water stress affect radar backscatter. Recent efforts have focused on linking these measurements to radar backscatter time series [5].

This presentation aims to present a journey across scales with respect to vegetation water stress. Measurements of changing plant physiological dynamics on leaf and plant levels are linked to radar backscatter on field and forest scales. We aim to demonstrate new insights obtained using field measurements, and highlight the potential of vegetation water stress detection using radar remote sensing.


References
[1]. Friesen, Jan, Susan C. Steele-Dunne, and Nick van de Giesen. "Diurnal differences in global ERS scatterometer backscatter observations of the land surface." IEEE Transactions on Geoscience and Remote Sensing 50.7 (2012): 2595-2602.

[2]. Frolking, Steve, et al. "Tropical forest backscatter anomaly evident in SeaWinds scatterometer morning overpass data during 2005 drought in Amazonia." Remote Sensing of Environment 115.3 (2011): 897-907.

[3]. van Emmerik, Tim, et al. "A comparison between leaf dielectric properties of stressed and unstressed tomato plants." Geoscience and Remote Sensing Symposium (IGARSS), 2015 IEEE International. IEEE, 2015.

[4]. van Emmerik, Tim, et al. "Dielectric Response of Corn Leaves to Water Stress." IEEE Geoscience and Remote Sensing Letters 14.1 (2017): 8-12.

[5]. van Emmerik, Tim, et al. "Impact of diurnal variation in vegetation water content on radar backscatter from maize during water stress." IEEE Transactions on Geoscience and Remote Sensing 53.7 (2015): 3855-3869.