The role of spatial data and geomatic approaches in treeline mapping: a review of methods and limitations

Abstract

In the debate over global warming, treeline position is considered an important ecological indicator of climate change. Currently, analysis of upward treeline shift is often based on various spatial data processed by geomatic techniques. In this work, considering a selection of 31 reference papers, we assessed how the scientific community is using different methods to map treeline position and/or shifts using spatial datasets. We found that a significant number of published studies suffer from a low degree of awareness of processed data, which outcomes in potentially unreliable results that may compromise the validity of inference from the studies. Moreover, we propose an operational approach for easily incorporating consideration of spatial data quality, so as to improve reliability of results and better support ecological conclusions. Finally, we present a simulation of potential treeline vertical error for the Alpine region of Northern Italy, as driven by primary data quality.

Exploring Short-Term Climate Change Effects on Rangelands and Broad-Leaved Forests by Free Satellite Data in Aosta Valley (Northwest Italy)

“…Moreover, another compensating action could come from the surrounding forest areas that have been proved to tolerate summer heatwaves. These results find strong evidence in different studies in the literature [88][89][90][91][92][93][94][95][96][97][98][99]. Concerning on the variation between PMs in H1, H2 and H3 it can be said that in rangelands at different altitudes, the SOS had a more marked variation at high altitudes as can be seen from the gains (in Table 4A) as in the past the snow normally lasted longer, normally at the top rather than at the bottom of the valley.…”

Adoption of Digital Aerial Photogrammetry in Forest Planning: A Case Study of Canavese Forestry Consortium, NW Italy with Technical and Economic Issues

“…In the forestry sector, to guarantee a proper consistency between DAP measures and existing maps, horizontal accuracy has to be higher than that expected for the map scale the work is intended for. It is worth remembering that the theoretical precision of a map, in Italy, can be set as equal to 0.2 mm at the scale of the map [61]. Consequently, a 1:1000 scale map and a 1:2000 scale map have an "expected" horizontal accuracy of 0.1 and 0.2 m, respectively.…”