Abstract
Accurate identification of the spatiotemporal distribution of forest/grassland and cropland is necessary for studying hydro-ecological effects of vegetation change in the Loess Plateau, China. Currently, the accuracy of change detection of land cover using Landsat data in the loess hill and gully areas is seriously affected by insufficient temporal information from observations and irregular fluctuations in vegetation greenness caused by precipitation and human activities. In this study, we propose a method for continuous change detection for two types of land cover, mosaic forest/grassland and cropland, using all available Landsat data. The period with vegetation coverage is firstly identified using normalized difference vegetation index (NDVI) time series. The intra-annual NDVI time series is then developed at a 1-day resolution based on linear interpolation and S-G filtering using all available NDVI data during the period when vegetation types are stable. Vegetation type change is initially detected by comparing the NDVI of intra-annual composites and the newly observed NDVI. Finally, the time of change and classification for vegetation types are determined using decision tree rules developed using a combination of inter-annual and intra-annual NDVI temporal metrics. Validation results showed that the change detection was accurate, with an overall accuracy of 88.9% ± 1.0%, and a kappa coefficient of 0.86, and the time of change was successfully retrieved, with 85.2% of the change pixels attributed to within a 2-year deviation. Consequently, the accuracy of change detection was improved by reducing temporal false detection and enhancing spatial classification accuracy.
Highlights
Along with the rapid development of China’s economy over the past few decades, China is facing a variety of environmental issues related to desertification, sandstorms, water and soil erosion, and land degradation [1]
Since 1978, the Chinese government has launched a series of ecological restoration programs to mitigate these increasingly devastating environment problems, including the ‘Three North’ Shelterbelt Development Program (TNSDP) [2], the Beijing–Tianjin Sand Source Control Program (BSSCP) [3], the Nature Forest Conservation Program (NFCP) [4], and the Grain to
Previous studies revealed that a significant decrease in runoff and sediment has been observed in the main streams and tributaries of the Yellow River [9], and dramatic changes in vegetation types in the Loess Plateau were reported to be an underlying reason for a decrease in runoff and sedimentation in the Yellow River Basin (YRB) [10,11]
Summary
Along with the rapid development of China’s economy over the past few decades, China is facing a variety of environmental issues related to desertification, sandstorms, water and soil erosion, and land degradation [1]. Water and soil erosion resulting from vegetation degradation in the Loess Plateau have resulted in serious eco-environmental and socioeconomic problems in the Yellow River Basin (YRB) of China [6]. Previous studies revealed that a significant decrease in runoff and sediment has been observed in the main streams and tributaries of the Yellow River [9], and dramatic changes in vegetation types in the Loess Plateau were reported to be an underlying reason for a decrease in runoff and sedimentation in the YRB [10,11]. Data describing forest/grassland and cropland land cover change has been indispensable for studying related scientific problems associated with runoff and sediment change of tributaries and the ecological benefits of dynamic vegetation change in the Loess Plateau
Sign-in/Register to view highlights & summary 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.
