基于RS和GIS的九龙江河口三角洲沉积面积时空变化研究

Temporal and Spatial Variation of Sedimentary Area in the Delta of the Jiulong River Estuary Based on RS and GIS

河流入海三角洲是海陆相互作用的产物,沉积物不断通过河流输送并沉积至入海口地区,形成河口三角洲,三角洲的形成和时空变化反映了河口沉积环境变化特征.本文利用遥感技术(RS)和地理信息系统技术(GIS),对九龙江河口三角洲1985~2017年8期Landsat遥感影像进行目视解译,分析三角洲时空变化特征并探讨其影响因素.结果表明:1)九龙江三角洲在1985~2017年总体从洲尾向下游扩张,增加了近16.0km2,增幅达24.0%;2)近30年来三角洲面积时空变化主要受河流沉积动力影响;3)三角洲沉积面积变化趋势,区域地形、气候、水文等自然特征以及河口沉积学原理表明,短期内九龙江三角洲有继续从洲尾向下游扩张趋势.

River deltas are the product of the interaction between land and sea. Sediments are continuously transported through rivers and deposited into estuaries of rivers to form deltas. The formation and spatiio-temporal changes of delta reflect the changing characteristics of river sedimentary environment. In this study, remote sensing (RS) and geographic information system technology (GIS) were used to carry out visual interpretation of eight Landsat remote sensing images of the Jiulong river estuary delta in the period of 1985~2017. The spatio-temporal variation characteristics of the Jiulong river delta were analyzed and their influencing factors and future development trends were discussed. The results showed that: 1) from 1985 to 2017, the Jiulong river estuary delta had a significant expansion toward the delta tail. The trend of expansion increased by nearly 20 km2, an increase of 23%;2) in recent 30 years, the spatial and temporal variation characteristics of delta area are mainly influenced by the river sedimentary dynamics. 3) According to the changing trend of the delta area in the recent 30 years, the regional topography, climate and hydrology, and the estuarine sedimentary theory, the Jiulongriver Delta will continue to expand in the future.