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Karst rocky desertification is one of the major ecological and environmental problems that threaten the sustainable development of southwestern China. It is caused by irrational and intensive land-use patterns in karst geo-ecological environment. Therefore, it is vital to identify how human forces work on this degraded environment. Based on the soil erosion information in 2000 and remote sensing images of Guanling County collected in 2000 and 2007, four grades of karst rocky desertification data in 14 villages of Guanling County were extracted. Impacts of population, affluence, and other human forces on karst rocky desertification were analyzed using STIRPAT model. The results show that: 1) Factors of population and affluence had strong influence on karst rocky desertification. In the STIRPAT model analysis, the population and affluence coefficients were positive, indicating that the increase in population and affluence would lead to more serious desertification. 2) Factors of farmer correlated with karst rocky desertification negatively, especially the way of viewing the relationship between people and nature, and the level of knowledge about rocky desertification. Government behavior was not a significant factor in this analysis. 3) The findings provide evidence that STIRPAT model can be used to analyze the relationship between human driving forces and rocky desertification. [ABSTRACT FROM AUTHOR]

Based on Landsat TM data, the temporal and spatial variations and driving factors of vegetation in Luxi County in recent 31 years were studied, and then the ecological benefits of rocky desertification control project were explored. The results show that: (1) In the past 31 years, the vegetation coverage of Luxi County showed an increasing trend, a sudden change point of time in 2001, and the growth rate increased from 0.35%/10a to 0.63%/10a, which coincided with the time point of national rocky desertification control project; The region with high vegetation coverage mainly distributes in the eastern and southern mountainous areas of Luxi County, while the region with low vegetation coverage mainly distributes at the junction of the central and Northern towns. The spatial distribution of the abrupt change from 2001 to 2010 coincides with the high value area. (3) From 1986 to 2016, vegetation coverage in Luxi County showed an increasing and decreasing trend, accounting for 85.21% and 14.79% respectively, with the most significant increase in the area change, from 7.71% before treatment to 21.62% after treatment; (4) Before and after treatment, only the vegetation of Quaternary and carbonate intercalation showed a change in lithologic conditions. The degradation trend is caused by the expansion of cities. After 2000, 79.6% of Luxi County's vegetation coverage was positively affected by human activities, 20.4% was negatively affected, 29.3% was affected by meteorological factors, and 70.7% was affected by human activities, especially by rocky desertification control projects. [ABSTRACT FROM AUTHOR]

• Karst vegetation had a consistent dynamic at the global level. • Karst vegetation dynamic depends more on precipitation than on temperature. • Karst vegetation can recover without human influences. • Ecological restoring programs contributed to karst vegetation recuperation. The vegetation in karst regions (KR) is crucial to maintain fragile local ecosystems. Therefore, it is critical to understand the factors that affect their vitality. The objective of this work is to study global KR vegetation dynamics between 1986 and 2015 and the natural and anthropogenic factors that affect it. The results showed a significantly (p < 0.05) positive greening trend (greening and browning trends were estimated to be 31.90% and 14.29%, respectively). The recuperation of KR vegetation was mainly observed at high latitudes and equatorial regions, where there is less human influence. Nevertheless, the growth of vegetation in some middle and low latitudes areas was a consequence of the human intervention. Vegetation degradation in KR was especially observed at middle latitudes due to the harsh environment and human impact. No significant correlation was observed between karst vegetation stability, the variation of annual average temperature and precipitation accumulated. Globally, karst vegetation dynamics depend more on precipitation than in temperature. In some areas, vegetation can recover gradually, even under extreme conditions and without human intervention. In areas with high population density, vegetation recuperation is mainly as a consequence of restoring programs. [ABSTRACT FROM AUTHOR]