Open AccessThis article is
- freely available
Trait Estimation in Herbaceous Plant Assemblages from in situ Canopy Spectra
KWR Watercycle Research Institute, Groningenhaven 7, P.O. Box 1072, 3430 BB Nieuwegein, The Netherlands
Systems Ecology, Department of Ecological science, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
Laboratory of Geo-Information Science and Remote Sensing, Wageningen University, Droevendaalsesteeg 3, 6708 PB Wageningen, The Netherlands
* Author to whom correspondence should be addressed.
Received: 23 September 2013; in revised form: 7 November 2013 / Accepted: 13 November 2013 / Published: 25 November 2013
Abstract: Estimating plant traits in herbaceous plant assemblages from spectral reflectance data requires aggregation of small scale trait variations to a canopy mean value that is ecologically meaningful and corresponds to the trait content that affects the canopy spectral signal. We investigated estimation capacities of plant traits in a herbaceous setting and how different trait-aggregation methods influence estimation accuracies. Canopy reflectance of 40 herbaceous plant assemblages was measured in situ and biomass was analysed for N, P and C concentration, chlorophyll, lignin, phenol, tannin and specific water concentration, expressed on a mass basis (mg∙g−1). Using Specific Leaf Area (SLA) and Leaf Area Index (LAI), traits were aggregated to two additional expressions: mass per leaf surface (mg∙m−2) and mass per canopy surface (mg∙m−2). All traits were related to reflectance using partial least squares regression. Accuracy of trait estimation varied between traits but was mainly influenced by the trait expression. Chlorophyll and traits expressed on canopy surface were least accurately estimated. Results are attributed to damping or enhancement of the trait signal upon conversion from mass based trait values to leaf and canopy surface expressions. A priori determination of the most appropriate trait expression is viable by considering plant growing strategies.
Keywords: field spectroscopy; plant traits; canopy surface; leaf surface; SLA; LAI; herbaceous plant assemblages; hyperspectral reflectance
Citations to this Article
Cite This Article
MDPI and ACS Style
Roelofsen, H.D.; van Bodegom, P.M.; Kooistra, L.; Witte, J.-P.M. Trait Estimation in Herbaceous Plant Assemblages from in situ Canopy Spectra. Remote Sens. 2013, 5, 6323-6345.
Roelofsen HD, van Bodegom PM, Kooistra L, Witte J-PM. Trait Estimation in Herbaceous Plant Assemblages from in situ Canopy Spectra. Remote Sensing. 2013; 5(12):6323-6345.
Roelofsen, Hans D.; van Bodegom, Peter M.; Kooistra, Lammert; Witte, Jan-Philip M. 2013. "Trait Estimation in Herbaceous Plant Assemblages from in situ Canopy Spectra." Remote Sens. 5, no. 12: 6323-6345.