Mismatch between Annual Tree-Ring Width Growth and NDVI Index in Norway Spruce Stands of Central Europe

Abstract

Presently, the forests of one of the most economically important tree species in Europe—Norway spruce [Picea abies (L.) Karst.]—have been disrupted and are in rapid decline due to a combination of several natural factors: extreme drought, heatwaves, and secondary damage caused by bark beetle outbreaks. The vulnerability of these forests has increased considerably over the past decade, and remote sensing methods can theoretically improve the identification of endangered forest stands. The main objective was to determine the relationship between remotely sensed characteristics of vegetation (using the normalized difference vegetation index—NDVI) and annual tree-ring growth in 180 trees through precipitation and air temperature. The research was conducted at six research plots in lowland spruce forests (319–425 m a.s.l.) in the central Czech Republic. No significant correlation between NDVI and annual ring width was observed. The primary factor limiting radial growth was lack of precipitation in the growing season; subsequently, spruce trees reacted negatively to air temperatures. A higher correlation with NDVI was observed on sites susceptible to drought, but overall, NDVI and RWI did not show similarities. This result describes that NDVI is a poor indicator for identifying low radial growth in Norway spruce stands on non-native localities in the studied area.

Short-Term Tree-Ring Series of Pinus hartwegii Lindl. Taken at Ground Level Correlate to Normalized Difference Vegetation Index Series

“…This confirms the reliability of tree-ring measurements in supporting remote sensing information to better understand forest growth and related processes, like carbon sequestration [37]. Some authors have reported weak and divergent correlations between the NDVI and tree-ring measurements of coniferous and deciduous species [38][39][40], but they used data from sensors of lower spatial resolution, which may explain this lack of significance. Mašek et al [13] reported that tree rings and the NDVI were decoupled for Pinus sylvetris and Abies picea; however, they suggested that topography is very important in explaining NDVI variation and tree growth.…”

Spatial and Temporal Variation in Primary Forest Growth in the Northern Daxing’an Mountains Based on Tree-Ring and NDVI Data

“…There is a loose linkage between tree-ring information and remote sensing data [17,18], and the magnitude of this linkage varies among climates, forest types, and environmental conditions. D'Andrea et al [19] explored forest decline using tree-ring and NDVI data and found that higher correlations between tree-ring and NDVI data were observed at drought-prone sites; a similar conclusion was obtained in Bunn et al [20]. Coulthard et al [21] suggested that the relationship between tree-ring and NDVI data might stem from the interaction between precipitation and stand differences.…”

Cutting the Greenness Index into 12 Monthly Slices: How Intra-Annual NDVI Dynamics Help Decipher Drought Responses in Mixed Forest Tree Species

“…The distribution of carbohydrates in tree structures can make it difficult to match NDVI and TRW values [52], for which reason it is recommended to extend observations of phenology and xylogenesis, as well as to extend the spatial and temporal resolution of the remote sensor. In other words, the delay of carbon allocation in radial stands may take longer than the period of analysis utilized here, depending on the physiological conditions of the tree, including its distribution priorities throughout its structures.…”