Abstract:
Zhalong National Nature Reserve is the largest and world-renowned wetland in China, and its vegetation changes have a significant impact on the ecological environment of the wetland. This study focuses on the Zhalong Wetland in Qiqihar City. Based on MODIS data, the pixel binary model method and ArcGIS 10. 2 software were used to analyze the spatiotemporal changes in vegetation cover of the wetland from 2001 to 2022. The aim is to reveal the trend of vegetation change in Zhalong Wetland, in order to provide reference and guidance for the ecological protection, restoration, and construction of the wetland. The results show that: 1) the vegetation coverage in the eastern region of Zhalong Wetland is better than that in the western region, and the overall spatial variation of vegetation coverage level shows a fluctuating increasing trend; The overall transformation is from low vegetation coverage to high vegetation coverage, with a significant increase in the area of high vegetation coverage, while the area of intermediate, medium, and low vegetation coverage gradually decreases. 2) There is a correlation between vegetation coverage and annual precipitation, average annual temperature, and annual water replenishment in the region. The high vegetation coverage area shows a significant positive correlation with annual precipitation and annual water replenishment(R=0. 42; R=0. 62), while the medium high vegetation coverage area shows a significant positive correlation with the annual average temperature of the previous year(R=0. 46), and also has a certain correlation with the annual average temperature of the current year; The high vegetation coverage area also has a certain correlation with the annual precipitation of the previous year, showing a characteristic that the change in vegetation coverage lags behind the change in precipitation.