Detecting leaf-water content in Mediterranean trees using high-resolution spectrometry

Water content of the vegetation canopy or individual leaves is an important variable in physiological plant processes. In Mediterranean regions where water availability is an important production limiting factor, it is a strong indicator of vegetation stress. Spectroscopic earth-observation techniques in the solar part of the electromagnetic spectrum provide opportunities to determine leaf and canopy-water content dueto the presence of water-absorption bands around 970 and 1200 nm. We investigated the possibilities to predict leaf-water content of three dominant tree species in a study area in Mediterranean Franceusing spectral indices. During a field campaign leaf-water content (EWT) was determined and high-resolution spectra were measured of the same leaves. The spectra were measured in two ways: using anoptical cable with a field of view of 25{ring operator}and using a leaf clip with its own artificial illumination source. The spectra were analyzed and related to leaf-water content as original reflectance spectra and as continuum-removed spectra using eight spectral leaf-water indices. Next, reflectance spectra were simulated to explore their sensitivity to environmental conditions like leaf area index and illumination angle using aradiative transfer model. Results show that a good correlation (0.70) exists between leaf-water content and spectral indices using the right slope of the 970 nm water-absorption band. Continuum-removal correction of the spectra improved the relations. The model sensitivity analysis illustrated that from aset of five environmental variables leaf area index has, as may be expected, an important impact on leaf-water estimates. This field and model study illustrates that it is feasible to determine foliar water contenton the basis of spectral indices located around the minor water-absorption bands with a limited effect of environmental conditions.

Tags
Data and Resources
To access the resources you must log in

This item has no data

Identity

Description: The Identity category includes attributes that support the identification of the resource.

Field Value
PID urn:URN:NBN:NL:UI:10-1874-301955
URL https://dspace.library.uu.nl/handle/1874/301955
Access Modality

Description: The Access Modality category includes attributes that report the modality of exploitation of the resource.

Field Value
Access Right Closed Access
Attribution

Description: Authorships and contributors

Field Value
Author de Jong, Steven M.
Author Addink, Elisabeth A.
Author Doelman, Jonathan C.
Publishing

Description: Attributes about the publishing venue (e.g. journal) and deposit location (e.g. repository)

Field Value
Collected From NARCIS
Hosted By Utrecht University Repository; NARCIS
Publication Date 2014-01-01
Additional Info
Field Value
Country Netherlands
Format image/pdf
Language English
Resource Type Article
keyword Management, Monitoring, Policy and Law
system:type publication
Management Info
Field Value
Source https://science-innovation-policy.openaire.eu/search/publication?articleId=dedup_wf_001::9198b2d0ac70d0753d292bde1de31646
Author jsonws_user
Last Updated 25 December 2020, 10:57 (CET)
Created 25 December 2020, 10:57 (CET)