A Global Assessment of Anthropogenic Geomorphology
Abstract
Human societies now act as a potent geomorphic agent that has already transformed landscapes across more than one-third of Earth's terrestrial surface. To interpret the extent, intensity, and form of human geomorphic fingerprints across Earth's land, it will be necessary to map and quantify distinctive anthropogenic geomorphic features at local and global scales. However, the proper indices to quantify surface processes pose a pivotal challenge to geomorphologists. Sofia et al. developed a geomorphological model capable of computing percentages of human-made alterations to terrain using high-resolution DTMs (Digital Terrain Models). These computations are highly dependent on the availability of fine-scale topographic data (eg. LiDAR data) which are not yet available at global scale. Nevertheless, the anthropogenic geomorphic features tend to reflect the socioeconomic and ecological patterns of human societies, so it may be possible to evaluate the topographic fingerprints of humanity based on correlations with spatial data on these patterns.
One of the most widely used spatial indicators of socioeconomic development at global scale is nighttime light data. Global maps of anthropogenic biomes (anthromes) also provide a useful classification of the globally significant patterns of human transformation of ecosystems. By combining these data, a global map of the sociocultural shapers of anthropogenic geomorphic features was prepared. Multiple study sites (10x10 km each) with different sociocultural and natural geomorphic conditions were then selected for more detailed analysis using high-resolution DTMs derived by LiDAR at 2 m resolution. The degree of anthropogenic geomorphic alteration was then assessed using the geomorphological model. Correlations between anthropogenic geomorphology and socioeconomic development were assessed by comparing these, using nighttime lighting intensity as a proxy for socioeconomic development. Results revealed that average correlations reached up to 90% for dense settlement anthromes and was about 70% across most village and cropland anthromes. Based on these correlations, we have produced the first global map of anthropogenic transformation of geomorphology.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFMGC41F1508C
- Keywords:
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- 1640 Remote sensing;
- GLOBAL CHANGEDE: 1803 Anthropogenic effects;
- HYDROLOGYDE: 1926 Geospatial;
- INFORMATICSDE: 4323 Human impact;
- NATURAL HAZARDS