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Spatial distribution of coniferous and deciduous tree covers based on four different global LC products and reference data from the Finnish MS-NFI. All data was aggregated and resampled to MODIS Climate Modeling Grid (CMG) resolution. The top row (a, c, e, g, i) shows tree cover values for coniferous and the lower row (b, d, f, h, j) for deciduous species. Note: black color is used to denote areas below the 10% CC threshold employed by the international forest definition by FAO
Source publication
Forest extent mapping is required for climate modeling and monitoring changes in ecosystem state. Different global land cover (LC) products employ simple tree cover (referred also as “forest cover” or even “vegetation cover”) definitions to differentiate forests from non-forests. Since 1990, a large number of forest extent maps have become availabl...
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Citations
... An important example is automated detection of trees and green spaces that are significant contributors to ecosystem services such as air purification and carbon sequestration. Recent studies include [1] and [2] for global monitoring of environment and forest cover using Sentinel-2 imagery. A Copernicus Sentinel-2B satellite, launched in 2017 provides 13 bands with spatial resolution from 10 m to 60 m. ...
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Context
In the past decades, several ecological engineering (eco-engineering) programs have been conducted in China, leading to a significant increase in regional carbon sink. However, the contribution of different eco-engineering programs to carbon uptake is still not clear, as the location of different programs is difficult to identify, and their impacts are concurrent with climate change.
Objectives
We aim to detect the location of eco-engineering programs and attribute the impacts of eco-engineering and climate change on vegetation dynamics and carbon uptake in Northeastern China during 2000–2020.
Methods
We developed a new framework to detect the location of eco-engineering programs by combining a temporal pattern analysis method and Markov model, and to attribute the impacts of eco-engineering and climate change on vegetation greenness and carbon uptake by combining a neighbor contrast method within a sliding window and trend analysis on the normalized difference vegetation index (NDVI) and gross primary production (GPP).
Results
We identified four main forestry eco-engineering programs: croplands to forest (CtoF), grasslands to forest (GtoF), savannas to forest (StoF), and natural forest conservation (NFC) programs, whose areas accounted for 2.11%, 1.89%, 3.41%, and 1.72% of the total study area, respectively. Both eco-engineering and climate change contributed to the increase in greenness and carbon uptake. Compared to climate change effect, eco-engineering increased NDVI and GPP by 121% and 21.43% on average, respectively. Specifically, the eco-engineering-induced increases in GPP were 54.1%, 9.46%, 8.13%, and 24.20% for CtoF, GtoF, StoF, and NFC, respectively.
Conclusions
These findings highlight the important and direct contribution of eco-engineering on vegetation greening with positive effects on carbon sequestration at a fine scale, providing an important implication for eco-engineering planning and management towards a carbon-neutral future.
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