未来海平面上升对黄河三角洲滨海湿地分布的影响及调控措施研究

Being rich in natural resources and beautiful in ecological environment, coastal wetlands of the YRD (YRD) not only play an important role of transit station and habitat breeding grounds for migratory birds along inland northeast Asia as well as western Pacific flyways, but also occupy an outstanding position in the oil field, agriculture and marine fisheries in China.. In recent decades, however, the sediment from the Yellow River into Bohai sea has been greatly reduced due to the large-scale water conservancy projects construction, soil and water conservation and returning farmland to forests and grassland measures in the upper and middle reaches of the Yellow River, which led to a significant decline in the promotion of delta development. Meanwhile, accelerated sea-level rise caused by global warming, and increasingly frequent and intense human activities in the context of rapid economic development in coastal areas have developed into the main factors affecting the evolution of coastal wetlands in the YRD gradually, causing the decrease of wetlands area, degradation of ecological functions of vegetation, and decline of species diversity and ecological services, which poses a serious threat to the sustainable development of regional society and economy.. In this study, variety data in terms of terrain, hydrology, vegetation, coastline, tides and climate are employed to forecast the impacts under the dual stress of sea-level rise and human activities in the future by field surveys, remote sensing monitoring, GIS analysis, scenario analysis and model simulation in the YRD coastal wetlands. And two aspects are focused on, firstly, exploring the historical evolutionary process and spatial pattern of coastal wetlands in the YRD, and identifying the driving forces and their characteristics; and secondly, forecasting the variations of sea-level rise and land use change under multiple scenarios in the future in the YRD region, for the purpose of revealing the evolution of coastal wetlands under the coupling effect of future sea-level rise and human activities. Expected results in this study can provide a theoretical basis and technical support for the regional adaptation to climate change and the coordinated development of ecological environment and social economy, as well as protection and management of coastal wetlands in the YRD.

黄河三角洲滨海湿地是我国北方沿海的宝贵资源和生态过渡带，但近几十年来，在海平面上升和人类活动的双重胁迫下，滨海湿地面积减少、植被生态功能退化、物种多样性衰减、生态服务功能下降，对区域经济社会的可持续发展构成了严重威胁。本项目以黄河三角洲滨海湿地为研究对象，基于地形、水文、植被、海岸线、潮汐以及气候等要素，通过野外调查、遥感监测、GIS分析以及情景分析和模型模拟等方法，研究：黄河三角洲滨海湿地历史演变的过程与格局，辨识驱动力及其影响特征；预测未来多情景下黄河三角洲区域海平面上升和土地利用变化的趋势和特征，揭示滨海湿地受未来海平面上升和人类活动耦合影响的演变规律。该研究将为区域应对气候变化和促进生态环境和社会经济的协调发展，以及滨海湿地的保护和管理等提供理论依据和技术支撑。

滨海湿地位于海陆交界带，在资源供给、环境保护以及提升气候韧性等方面发挥着重要作用。然而，滨海湿地生态环境脆弱敏感，生态系统极易受到环境变化的干扰和破坏。近几十年来，全球变暖导致的海平面上升和沿海地区频繁的人类活动对滨海湿的可持续发展造成了严重影响。尽管人们对滨海湿地的历史变化有了较深刻的认识，但尚缺乏对未来时期海平面上升情景下复合极端淹没风险和不同目标导向情景下人类活动对滨海湿地带来的陆海双向胁迫效应研究。. 首先，该项目基于遥感影像目视解译研究了2000-2020年黄河三角洲土地利用变化的时空特征、驱动力及其影响特征。其次，基于风暴潮、天文大潮和未来时期的海平面上升等数据量化了黄河三角洲区域不同回归期下的极端水位。然后，基于人口、GDP等社会经济数据以及DEM、海岸线等自然地理数据构建了SD-FLUS模型以模拟黄河三角洲2020–2100年的土地利用变化，揭示了未来时期不同目标导向的人类活动情景下滨海湿地的发展态势。最后，结合未来时期的极端水位以及滨海湿地的发展态势，量化了近（2030年）、中（2050年）和长期（2100年）黄河三角洲滨海湿地的淹没风险。. 结果表明，2000-2020年黄河三角洲滨海湿地面积大幅减少，而人工湿地和建设用地大幅增加。人工湿地和建设用地的大幅扩张以及海平面上升引起的侵蚀是黄河三角洲滨海湿地锐减的主要原因。未来时期，生态保护优先情景下滨海湿地将持续发展，经济发展优先情景下滨海湿地将不断萎缩。当考虑复合极端水位的影响时，当前黄河三角洲滨海湿地大部分区域面临淹没风险，与当前相比，未来时期各情景下滨海湿地的淹没态势会随着滨海湿地存量的变化而变化。面临严峻的极端水位淹没风险，亟需实施更有效的保护措施，例如，构建可供滨海湿地迁移且能有效阻挡洪水淹没的生态岸堤，以应对海平面上升对黄河三角洲滨海湿地构成的潜在威胁。