Analysis on regional vegetation changes in dust and sandstorms source area: a case study of Naiman Banner in the Horqin sandy region of Northern China

摘要

Dust and sandstorms are disastrous meteorological processes in arid and semi-arid regions and are also an important indicator for evaluating desertification levels. The Horqin sandy region is an important transit zone and affected area of East Asian dust and sandstorms in Northern China. Over the past decades, the Chinese government has initiated several major ecological construction and sand-source control programs to effectively reduce and lessen the occurrence of dust and sandstorms. Taking Naiman Banner as an example, this paper evaluated the dynamics of vegetation restoration at Horqin sandy land using both field survey and remote sensing monitoring. Results showed a decreasing trend of shifting dunes from 1975 to 2008 and an increasing trend of connected fixed dunes at the desertification region in the north of the study area from 1985 to 2008 due to the large scale of eco-restoration programs. The increase of the vegetation remnants coverage in the non-growing seasons was consistent with the improvement of vegetation productivity in the growing season, which could effectively help increase the topsoil's roughness in sandy land and ease soil wind erosion and desertification. In general, the regional vegetation environment maintained a benign circle. In particular, the effective vegetation restoration initiatives in the region will play a significant role in diminishing the occurrence of dust and sandstorms.