Reference:
DeFries, R.S., T. Rudel, M. Uriarte, and M. Hansen (2010). Deforestation driven by urban population growth and agricultural trade in the twenty-first century.Nature Geoscience, doi:10.1038/ngeo756.
+ Article abstract [external link]
+ City Dwellers Drive Deforestation in 21st Century, Scientific American [external link]

Above the Earth, Below the Surface: Landsat’s Role in Monitoring Water Quality
Safeguarding freshwater resources is crucial, and while scientists use a variety of ground-based techniques to gauge water quality, the Landsat program has provided water quality data from orbit for decades.