Phenopix: A R package for image-based vegetation phenology
Research output: Contribution to journal › Research article › Contributed › peer-review
Contributors
Abstract
In this paper we extensively describe new software available as a R package that allows for the extraction of phenological information from time-lapse digital photography of vegetation cover. The phenopix R package includes all steps in data processing. It enables the user to: draw a region of interest (ROI) on an image; extract red green and blue digital numbers (DN) from a seasonal series of images; depict greenness index trajectories; fit a curve to the seasonal trajectories; extract relevant phenological thresholds (phenophases); extract phenophase uncertainties.The software capabilities are illustrated by analyzing one year of data from a selection of seven sites belonging to the PhenoCam network (http://phenocam.sr.unh.edu/), including an unmanaged subalpine grassland, a tropical grassland, a deciduous needle-leaf forest, three deciduous broad-leaf temperate forests and an evergreen needle-leaf forest. One of the novelties introduced by the package is the spatially explicit, pixel-based analysis, which potentially allows to extract within-ecosystem or within-individual variability of phenology. We examine the relationship between phenophases extracted by the traditional ROI-averaged and the novel pixel-based approaches, and further illustrate potential applications of pixel-based image analysis available in the phenopix R package.
Details
Original language | English |
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Pages (from-to) | 141-150 |
Number of pages | 10 |
Journal | Agricultural and forest meteorology |
Volume | 220 |
Publication status | Published - 15 Apr 2016 |
Peer-reviewed | Yes |
Externally published | Yes |
External IDs
ORCID | /0000-0003-0363-9697/work/142252092 |
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Keywords
ASJC Scopus subject areas
Keywords
- Community ecology, Image analysis, Phenology, Pixel-based analysis