Inventory of ecological restoration projects on the coast of Mecklenburg-Western Pomerania, East German Baltic coast

Within the ECAS-Baltic project , we investigated coastal ecological restoration projects on the German Baltic Coast in the State of Mecklenburg- Western Pomerania. The restoration of near natural coastal hydrological regimes, flood plains and habitats, often involving coastal maanged retreat, is currently being performed for a number of conservation purposes (e.g., climate mitigation, habitat protection and restoration) and contribute to a more resilient coast. The articulation of these closely related goals is an interesting avenue for regional planing and coastal zone management, especially where planed measures are polemic and social acceptance fraught with obstacles. Our goals are: to produce a comprehensive and systematic inventory of coastal restoration projects involving (plans for) MR, to describe the projects identified with a focus on decision-making, planing and implementation, to determine factors that facilitate / hinder their successful implementation, and to reflect on MR potential for coastal zone management and regional planning. We developed a methodology to formalize rich, locally situated empirical data from practitioners to draw lessons learnt from past experiences and identify generic strategies towards resilient coastal land management. Our inventory includes 110 wetland restoration projects (as known up to June 2024), the majority of which (102) are located on agricultural polders on the inner coast of the eastern part of the state. All 110 projects attend conservation goals, such as the restoration of natural coastal processes and coastal habitats, in particular mires, reed beds and salt meadows. Secondary goals include the compensation of the environmental impacts of developments (37), and the optimisation of flood protection (22). In total, 90 projects involved some form of MR, 16 of which explicitly considered MR as a way to increase coastal resilience and reduce dike maintenance costs. 44 MR projects have either been implemented or are currently being implemented or planned, with the smallest project covering 25 ha and the largest 1.700 ha. 22 out of these 44 MR projects have been carried out to compensate the construction of transport (8), coastal protection (6), energy (6) and industrial (2) infrastructure. Our detailed inventory at subnational scale demonstrates that MR is far more commonly implemented than currently documented in the literature. It further helps to visualise current geographical patterns of distribution of ecological restoration projects at the coast of Mecklenburg-Western Pomerania and highlights significant potential for further projects, particularly on the coast east of the city of Rostock. With stronger impacts of climate change, increasing sea-levels and subsiding agricultural land (due, among other causes, to the mineralisation of peatlands as a consequence of reclamation), the need for a long-term strategy for the adaptation of agricultural polders becomes imminent.在ECAS-Baltic项目框架内，我们针对梅克伦堡-前波美拉尼亚州（Mecklenburg-Western Pomerania）境内的德国波罗的海沿岸海岸生态修复项目开展了研究。当前，多项以气候减缓、生境保护与修复等保护目标为导向的修复工作正在推进，内容涵盖恢复近自然海岸水文情势、洪泛平原与生境，其中常涉及海岸管理性后撤（managed retreat, MR），这些工作有助于打造更具韧性的海岸。对这些密切相关目标的统筹协调，是区域规划与海岸带管理的一项值得关注的方向，尤其当规划措施存在争议且社会接纳度面临诸多障碍时，该方向的意义更为凸显。 我们的研究目标如下： 1. 编制一份涵盖（规划中的）海岸管理性后撤（MR）相关海岸修复项目的全面系统清单； 2. 以决策制定、规划与实施为核心，对所识别的项目进行详细描述； 3. 明确助力或阻碍项目顺利实施的影响因素； 4. 探讨海岸带管理与区域规划中MR的应用潜力。 我们开发了一套方法体系，用于将从业者收集的丰富本地化实地实证数据进行规范化整理，以汲取过往实践的经验教训，并总结出适配韧性海岸土地管理的通用策略。 本次清单共收录截至2024年6月已知的110个湿地修复项目，其中102个位于该州东部内海岸的农业圩田之上。所有110个项目均以生态保护为核心目标，包括恢复自然海岸过程与海岸生境，尤以泥炭地、芦苇床与盐沼为修复重点。次要目标包括补偿开发活动造成的环境影响（共37个项目）以及优化防洪能力（共22个项目）。 总计90个项目采用了某种形式的MR，其中16个项目明确将MR作为提升海岸韧性、降低堤防维护成本的手段。44个MR项目已实施、正在实施或处于规划阶段，项目规模最小为25公顷，最大为1700公顷。上述44个MR项目中，有22个为补偿交通（8个）、海岸防护（6个）、能源（6个）与工业（2个）基础设施建设所开展。 我们在次国家级尺度开展的详细清单研究表明，MR的实际实施频次远高于当前文献所记载的水平。该清单还有助于直观呈现梅克伦堡-前波美拉尼亚州沿岸生态修复项目的当前地理分布格局，并凸显了后续项目的巨大潜力，尤其是在罗斯托克市以东的海岸区域。随着气候变化影响加剧、海平面上升以及农业圩田因围垦导致泥炭矿化等原因出现沉降，制定农业圩田长期适应策略的需求已迫在眉睫。