Using remote sensing energy balance and evapotranspiration to characterize montane landscape vegetation with focus on grass and pasture lands

• Type: Article in International Scientific Journal
• Date: 2013

Authors

Isabel Pÿças (Author) Other; Mário Cunha (Author) FCUP; Luís S Pereira (Author) Other; Richard G Allen (Author) Other

Journal

Title: International Journal of Applied Earth Observation and Geoinformation

Vol. 21

Pages: 159-172

ISSN: 0303-2434

Publisher: International Institute for Aerial Survey and Earth Sciences

Indexing

ISI Web of Knowledge - 40 Citations

Scopus - 45 Citations

Other information

Authenticus ID: P-001-ZZZ

DOI: 10.1016/j.jag.2012.08.017

Abstract (EN): Water and energy balance interactions with vegetation in mountainous terrain are influenced by topographic effects, spatial variation in vegetation type and density, and water availability. This is the case for the mountainous areas of northern Portugal, where ancestral irrigated meadows (lameiros) are a main component of a complex vegetation mosaic. The widely used surface energy balance model METRIC was applied to four Landsat images to determine the spatial and temporal distribution of the energy balance terms in the identified land cover types (LCT). A discussion on the variability of evapotranspiration (ET) through the various vegetation types was supported by a comparison between the respective crop coefficients and those available in the literature corresponding to the LC, which has shown the appropriateness of METRIC estimates of ET. METRIC products derived from images of May and June - NDVI, surface temperature, net radiation, soil heat flux, sensible heat flux, and ET - were used to characterize the LCTs, through application of principal component analysis. Three principal components explained the variance of observed variables and their varimax rotated loadings allowed a good explanation of the behaviour of the explanatory variables in association with the LCTs. Information gained contributes to improve the characterization of the study area and may further support conservation and management of these mountain landscapes.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 14