Water and ecological security: dealing with hydroclimatic challenges at the heart of China's Silk Road

摘要

The Tarim Basin is the heart of China's Silk Road Economic Belt. The contradiction between economic growth and environmental protection is particularly evident in the basin region. For the past 20 years, the groundwater has been increasingly overused, causing water tables to decline precipitously. In the past decade in particular, the total water storage (TWS) in the basin has undergone a significant decreasing trend, losing around -13 x 10(8) m(3)/year from 2002 to 2013. Prior to 1998, the normalized difference vegetation index (NDVI) of natural vegetation exhibited an increasing trend at a rate of 0.012 per decade, but from 1999 onwards, the NDVI started decreasing at a rate of 0.005 per decade. In the 2000s, the bare soil areas of the Taklamakan Desert boundaries expanded by 7.8 %. At the same time, the effects of global warming on water and ecological systems are likewise intensifying in the Tarim Basin. The increases in warming have outpaced increases in precipitation, and the negative effects of climate change on the region's vulnerable ecology have intensified. Potential changes in the usage of limited water resources may further increase the risk of desertification and deepen the area's ecological poverty. Excessive water use and over allocation, including over-pumping of groundwater, are themain factors causing the loss of groundwater, the depletion of total water storage, and the overall ecological degradation, but these are being exacerbated by global warming. To address all of these issues in a holistic way, a unified management mechanism that encompasses both surface water and groundwater must be developed, and the implementation of the government plan to return farmland to natural vegetation should be speed up.