Land eco-security evaluation in the Shule River Basin during 2005-2014 in Gansu Province, China

The Shule River Basin is an ecologically fragile area in arid zone. To understand the state of land eco-security, the Environment-Economic-Society model was applied to build a land eco-security evaluation index system in the Shule River Basin. An entropy-weighted and matter-element model was built for eco-security evaluation from 2005 to 2014. Principal component analysis was used to quantitatively study the limiting factors of land ecological security. The result showed: the direction of development of the state of land eco-security in the Shule River Basin from 2005 to 2014 was characterized by "unsafe (No-4) -> safe (No-1)," and presented an upward trend. The land eco-security status during 2005-2007 was in the "Unsafe" state and the state changed to "Critical Safe" in 2008-2009, "Safer" in 2010-2011, but "Safe" in 2012-2014. The key factors that affected land eco-security in the Shule River Basin were Per Capita Arable Land, Forest Cover Rate, Per Capita Water Resources, Water Production Modulus, the Tertiary Industry Output Value, and GDP Ratio and Water Consumption. Among them, Forest Cover Rate and Water Production Modulus had the greatest impact, with principal component loads of up to 0.973 and 0.968, respectively. The result of this study is expected to serve as reference and support for the conservation and management of Shule River Basin to ensure sustainable development.