Changes Detection and Object-Oriented Classification of Major Wetland Cover Types in Response to Driving Forces in Zoige County, Eastern Qinghai–Tibetan Plateau

Abstract

The Zoige Alpine Wetland of eastern Qinghai-Tibetan Plateau is one of the most important wetlands in the world, which suffered stronger human regulations of decades' drainage and recent restoration. It is so fragile that great efforts should be made to strengthen wetland protection. Based on wetland type classification for 7 periods by the object-oriented classification method, we quantitatively discussed dynamically changes of wetland cover types and their driving forces.Conclusions show that alpine meadows accounts for 44.59% of the whole area of the county, and the transition between alpine meadows and swamp meadows mostly occurs in the process of wetland landscape changes. Changes of wetland cover types have taken place in Zoige County from 1990 to 2018 in which wetland loss was mainly caused by the decrease of marsh areas during 1995-2005. Particularly, shift from alpine meadows to swamp meadows led to wetland slightly expansion in two periods, that is, 1990-1995 and 2005-2018. There is a significant negative correlation between marsh area and average temperature in growing season, average wind speed and rural population, and a significant negative correlation between water area and maximum wind speed. The increase of air temperature and wind speed lead to an enhancement of surface evapotranspiration and a decrease of water retention capacity. Whereas, positive feedback of ecosystem lead to an increase in air temperature and a decrease of marsh area. Both climatic changes and human activities have caused changes in wetland cover type, especially temperature in growing season, wind speed, agricultural development, and animal husbandry.

Changes and driving forces analysis of alpine wetlands in the first meander of the Yellow River based on long-term time series remote sensing data

“…From 2010 to 2020, the area of alpine wetlands increased annually, but compared with the 1990s, the wetland shrinkage was still severe. These results were consistent with those of other studies that investigated changes in the wetland landscape of key counties within the region (Shen et al, 2019b;Li W. et al, 2020;Zhang et al, 2021).…”

“…Studies of the dual response of wetland landscape changes to the natural environment and human productivity in high-altitude ecologically sensitive areas have become a popular topic in this field, particularly as global warming and human activities intensify (Shen et al, 2014;Li et al, 2021). When considering the primary factors of wetland degradation, climate change is the most important factor over a small-scale spatiotemporal range, particularly for remote river sources and high-altitude regions (Wang et al, 2020;Zhang et al, 2021;Zhang B. et al, 2022). Wetland ecosystems do not simply respond to natural changes and the impact of human activities and the interaction between various natural factors must also be considered.…”

Integrating Hydrological Connectivity in a Process–Response Framework for Restoration and Monitoring Prioritisation of Floodplain Wetlands in the Ramganga Basin, India

“…A recent wetland-scale implementation is the use of Wetland Cover Types (WCT) approach that exploits satellite imageries to classify the wetland covers. The WCT approach [16][17][18][19][20] could include, but not limited to, on-screen digitization [21], thresholding of multispectral indices e.g., [17,20], and object-oriented classification e.g., [18,19]. Other approaches for wetland-scale assessment involve the use of various landscape, physical, chemical, biological, and social indicators e.g., [22][23][24].…”