Abstract
Verification of restoration policies that have been implemented is of significance to simultaneously reduce global environmental risks while also meeting economic development goals. This paper proposed a novel method according to the idea of multiple time scales to verify ecological restoration policies in the Shiyang River drainage basin, arid China. We integrated modern pollen transport characteristics of the entire basin and pollen records from 8 Holocene sedimentary sections, and quantitatively reconstructed the millennial-scale changes of watershed vegetation zones by defining a new pollen-precipitation index. Meanwhile, Empirical Orthogonal Function method was used to quantitatively analyze spatial and temporal variations of Normalized Difference Vegetation Index in summer (June to August) of 2000–2014. By contrasting the vegetation changes that mainly controlled by millennial-scale natural ecological evolution with that under conditions of modern ecological restoration measures, we found that vegetation changes of the entire Shiyang River drainage basin are synchronous in both two time scales, and the current ecological restoration policies met the requirements of long-term restoration objectives and showed promising early results on ecological environmental restoration. Our findings present an innovative method to verify river ecological restoration policies, and also provide the scientific basis to propose future emphasizes of ecological restoration strategies.
Highlights
Key Laboratory of Western China’s Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Center for Hydrologic Cycle and Water Resources in Arid Region, Lanzhou University, Lanzhou, 730000, China
The results of the discriminant analysis confirm that the six vegetation regions have distinctive palynological signatures as represented by the six pollen assemblages (Fig. 1), and a comparison of the predicted group memberships with the a priori groups shows that 86.7% of the samples are correctly classified (Supplementary Table 4, 5)
Two major groupings are indicated by Hierarchical cluster analysis (HCA) and the palynological identification of these groups may provide a useful basis for palaeoenvironmental reconstruction (Supplementary Figure 8)
Summary
Key Laboratory of Western China’s Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Center for Hydrologic Cycle and Water Resources in Arid Region, Lanzhou University, Lanzhou, 730000, China. The Shiyang River, which originates from the Qilian Mountains and flows northeast toward the Gobi Desert, is located in the northeast of the Qinghai-Tibet Plateau, the eastern Hexi Corridor, arid China (Fig. 1). Climate of the Shiyang River drainage basin is mainly affected by the Asian monsoon system and the mid-latitude westerly winds[16]. The length of the drainage path is about 300 km, and the catchment area of the Shiyang River is about 41600 km[2], which is roughly at geographical coordinates of 100°57′– 104°57′E, 37°02′– 39°17′N. The Shiyang River drainage basin, which is one of three major rivers in arid northwest China, is the region where the ecological environment problems in arid areas are most prominent[14]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
