Mapping the annual dynamics of cultivated land in typical area of the Middle-lower Yangtze plain using long time-series of Landsat images based on Google Earth Engine
Mapping the annual dynamics of cultivated land in typical area of the Middle-lower Yangtze plain using long time-series of Landsat images based on Google Earth Engine
复制标题
基于Google Earth Engine的Landsat长时间序列影像绘制长江中下游平原典型区耕地年动态
DOI：
10.1080/01431161.2019.1673917
复制
发表时间：
2020-02-16
影响因子：
3.4
通讯作者：
Zhang, Han
中科院分区：
文献类型：
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作者：
Jin, Yuhao;Liu, Xiaoping;Zhang, Han
摘要长江中下游平原的耕地面积在过去的几十年里由于城市的快速扩张和大规模的城市建设而大大减少。准确及时地监测耕地变化对区域粮食安全和国家土地政策对耕地动态的影响具有重要意义。然而，由于计算资源的限制和复杂地区土地覆盖的多样性，在复杂地区生成高分辨率的耕地动态时空记录仍然很困难。利用30 m分辨率的遥感影像，以1990- 2010年长江中下游平原耕地为研究对象，分别利用增强型时空自适应反射融合模型（ESTRAFM）提取的归一化植被指数（NDVI）和合成植被指数（NDVI），分析了植被和耕地的年际变化。最后，通过对物候特征的检测，提取了以一年为间隔的耕地动态。结果表明：近20年来，耕地面积减少速度加快，1997年以来，耕地面积减少趋势加剧;耕地面积变化主要发生在山区、丘陵、湖泊和城镇周边地区，变化频率以1 ~ 2次为主。尤其是南京的耕地变化最为剧烈，这或许要归功于城市绿化和基础设施建设。
ABSTRACT Cultivated land in Middle-lower Yangtze Plain has been greatly reduced over the last few decades due to rapid urban expansion and massive urban construction. Accurate and timely monitoring of cultivated land changes has significant for regional food security and the impact of national land policy on cultivated land dynamics. However, generating high-resolution spatial-temporal records of cultivated land dynamics in complex areas remains difficult due to the limitations of computing resources and the diversity of land cover over a complex region. In our study, the annual dynamics of cultivated land in Middle-lower Yangtze Plain were first produced at 30 m resolution with a one-year interval in 1990–2010.Changes of vegetation and cultivated land are examined with the breakpoints inter-annual Normalized Difference Vegetation Index (NDVI) trajectories and synthetic NDVI derived by the enhanced spatial and temporal adaptive reflectance fusion model (ESTRAFM), respectively. Last, cultivated land dynamics is extracted with a one-year interval by detecting phenological characteristic. The results indicate that the rate of reduction in cultivated land area has accelerated over the past two decades, and has intensified since 1997.The dynamics of cultivated land mainly occurred in the mountains, hills, lakes and around towns, and the change frequency of these area was mainly one or two times. In particular, the changes in cultivated land in Nanjing have been most intense, perhaps attributed to urban greening and infrastructure construction.