Characterization of seasonal variation of forest canopy in a temperate deciduous broadleaf forest, using daily MODIS data

Authors

Qingyuan Zhang, University of New Hampshire - Main Campus
Xiangming Xiao, University of New Hampshire - Main Campus
Rob Braswell, University of New Hampshire - Main CampusFollow
Ernst Linder, University of New HampshireFollow
Scott V. Ollinger, University of New Hampshire - Main CampusFollow
Marie-Louise Smith, U.S.D.A. Forest Service, Washington, DC
J P. Jenkins, University of New Hampshire - Main Campus
Fred Baret, Institut National de la Recherche Agronomique, France
Andrew D. Richardson, University of New HampshireFollow
B Moore, University of New Hampshire - Main CampusFollow
Rakesh Minocha, USDA Forest ServiceFollow

Abstract

In this paper, we present an improved procedure for collecting no or little atmosphere- and snow-contaminated observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. The resultant time series of daily MODIS data of a temperate deciduous broadleaf forest (the Bartlett Experimental Forest) in 2004 show strong seasonal dynamics of surface reflectance of green, near infrared and shortwave infrared bands, and clearly delineate leaf phenology and length of plant growing season. We also estimate the fractions of photosynthetically active radiation (PAR) absorbed by vegetation canopy (FAPAR_canopy), leaf (FAPAR_leaf), and chlorophyll (FAPAR_chl), respectively, using a coupled leaf-canopy radiative transfer model (PROSAIL-2) and daily MODIS data. The Markov Chain Monte Carlo (MCMC) method (the Metropolis algorithm) is used for model inversion, which provides probability distributions of the retrieved variables. A two-step procedure is used to estimate the fractions of absorbed PAR: (1) to retrieve biophysical and biochemical variables from MODIS images using the PROSAIL-2 model; and (2) to calculate the fractions with the estimated model variables from the first step. Inversion and forward simulations of the PROSAIL-2 model are carried out for the temperate deciduous broadleaf forest during day of year (DOY) 184 to 201 in 2005. The reproduced reflectance values from the PROSAIL-2 model agree well with the observed MODIS reflectance for the five spectral bands (green, red, NIR₁, NIR₂, and SWIR₁). The estimated leaf area index, leaf dry matter, leaf chlorophyll content and FAPAR_canopy values are close to field measurements at the site. The results also showed significant differences between FAPAR_canopy and FAPAR_chl at the site. Our results show that MODIS imagery provides important information on biophysical and biochemical variables at both leaf and canopy levels.

Department

Earth Sciences, Earth Systems Research Center

Publication Date

12-15-2006

Journal Title

Remote Sensing of Environment

Publisher

Elsevier

Digital Object Identifier (DOI)

10.1016/j.rse.2006.06.013

Document Type

Article

Recommended Citation

Qingyuan Zhang, Xiangming Xiao, Bobby Braswell, Ernst Linder, Scott Ollinger, Marie-Louise Smith, Julian P. Jenkins, Fred Baret, Andrew D. Richardson, Berrien Moore III, Rakesh Minocha, Characterization of seasonal variation of forest canopy in a temperate deciduous broadleaf forest, using daily MODIS data, Remote Sensing of Environment, Volume 105, Issue 3, 15 December 2006, Pages 189-203, ISSN 0034-4257, http://dx.doi.org/10.1016/j.rse.2006.06.013.

Rights

Copyright © 2006 Elsevier Inc. All rights reserved.