Determination of land degradation causes in Tongyu County, Northeast China via land cover change detection

Change of surface cover greenness in China between 2000 and 2010

“…Between 1996 and 2001, land degradation in Qinghai-Tibet Plateau turned to be serious, with increased desertification at an annual rate of about 1.8% [13]. Tongyu is located in northwest of Jilin Province, whose desertification area expanded to 4214 km 2 by 2400 km 2 from 1992 to 2002 [14]. Desertification area in Horqin grassland, the border area between Inner Mongolia and Liaoning Province, changed from 22423.1 to 22422.4 km 2 between 2000 and 2005, which was quite stable, but their work analyzed desert land area only, leaving the overall change of greenness in that region unevaluated [15].…”

“…Regions located in the east which have large population can have more serious situation of desertification due to frequent human activities including urbanization, excessive reclamation, farming, grazing and deforestation [9,10,14], which makes human intervention the main factor. At the same time, human intervention could also become driving force to restrain desertification, such as the construction of the three north shelter forests and the grain for green policy in China.…”

“…Hot spots such as Inner Mongolia, Horqin grassland, Hulunbuir, Ordos, Qinghai-Tibet Plateau, Minqin, and the three north shelter forests, are major focal areas of previous remote sensing research [9][10][11][12][13][14][15][16][17][18][19][20][21][22], and there is no desertification analysis about the whole territory of China. Time series data used in existing research are mostly before 2000, incomplete since 2000 to nowadays [9][10][11][12][13][14][15][16][17][18][19][20][21][22], and there is still no report for the time period of 2000 and 2010. Therefore, in this paper we aim to map China's desertification between 2000 and 2010 based on international standard and definition of desertification, and the capability of remote sensing technology, in order to lay a foundation for China's long-term remote sensing monitoring of desertification.…”

The role of Remote Sensing in land degradation assessments: opportunities and challenges

“…Call for multi-scale assessment of LD Currently, there are still ongoing discussions and unresolved questions related to the use of satellite Remote Sensing to address LD, including but not limited to methodological issues, such as • choice of LD proxy when mapping vegetation cover and productivity changes at different spatial/temporal scales (Prince, Wessels, Tucker, & Nicholson, 2007;Tüshaus et al, 2014); • data/method selection for multi-temporal analysis Wessels, van den Bergh, & Scholes, 2012); • analysis of the drivers of LD at different spatial/ temporal scales (Bai et al, 2008;Gao & Liu, 2010;Reed et al, 2011); • decoupling environmental signals due to shortterm climatic variability and land management from long-term resource degradation (Nkonya et al, 2016a;Stavi & Lal, 2015); and • validation of the Remote Sensing results against in situ data ( Karnieli et al, 2013;Le, Tamene, & Vlek, 2012;Safriel, 2007).…”

“…Among different methods for studying and monitoring LD, Remote Sensing provides a cost-effective evaluation over extensive areas, whereas in situ process studies are resource demanding, and thus, are usually conducted at a field level (e.g. Bai & Dent, 2009;Prince et al 2009;Gao & Liu, 2010;Vlek, Le, & Tamene, 2008). In addition, satellite-based assessment is currently the only means for LD monitoring at different spatial and temporal scales in a spatially explicit and continuous manner, specifically in the less developed countries where funds for SLM programs are often limited (Sivakumar and Stefanski 2007).…”