Prioritising riparian ecotones to sustain and connect multiple biodiversity and functional components in river networks

欧洲已承诺加强生态系统保护，包括30%的陆地和海洋。然而，由于历史上对自然资产的过度开发，可用于生物多样性保护的区域受到严重限制。河岸带是水生生态系统和陆地生态系统之间的自然交错带，对区域生物多样性的贡献不成比例，并提供多种生态系统功能和服务。由于这一点及其分支的几何形状，河岸网络形成了一个巨大的“蓝绿色动脉”系统，它在物理和功能上连接了海拔梯度上的多个生态系统，尽管覆盖了相对较小的流域面积。因此，我们认为，开发能够优化自然河流河岸网络的空间保护优先级的方法代表了欧盟生物多样性保护的一个旗舰例子。虽然河岸带的完整性是实现多个欧盟环境目标的基础，但由于成员国缺乏标准化的生物多样性评估和保护框架，导致河岸区受到广泛损害，利益相关者冲突频繁。RIPARIANET的主要目标是利用日益提高的遥感信息分辨率，为从业人员提供以证据为基础的生物多样性保护指导和方法。关键问题包括：i）我们如何能够远程评估河岸完整性，并确定提供有效连通性的地区，使物种生物多样性和生态系统功能能够通过元生态过程持续存在？ii）我们如何能够理清当地和网络规模的压力和河岸生物多样性的过程，以更好地实施河流流域管理计划的影响？（iii）现有的河流保护区在多大程度上解释了河岸网络的几何形状及其多功能性？我们将解决这些问题的河岸网络在欧洲的六个河流流域，包括北方，大陆，高山，温带和地中海系统。首先，我们将收集当地主要利益相关者的需求和利益，以及所有流域的卫星图像和地理信息系统环境数据。然后，将模拟河岸和河流生态系统功能，并通过基于GIS的多标准，包括利益相关者的投入，确定生态热点。然后，我们将收集现场数据，以评估当地规模的多种生物多样性和压力源，随后，使用地质统计工具和先进的建模将这些信息扩展到网络规模。这些知识将以决策支持工具的形式传达给地方和欧盟各级的管理人员，使决策者能够根据多种生物多样性、功能和连通性标准，确定保护差距和沿着河岸网络的生态热点。

Europe has committed to upscale ecosystems protection to include 30% of land and sea. However, due to historical overexploitation of natural assets the available area for biodiversity protection is severely limited. Riparian zones are natural ecotones between aquatic and terrestrial ecosystems, contributing disproportionately to regional biodiversity, and providing multiple ecosystem functions and services. Because of this and their branching geometry, riparian networks form a vast system of ‘blue-green arteries’ which physically and functionally connect multiple ecosystems over elevation gradients, despite covering a relatively small area of the basin. Hence, we argue that developing approaches able to optimise the spatial conservation prioritisation of natural stream-riparian networks represent a flagship example of biodiversity protection in the EU. Although the integrity of riparian zones is fundamental for the achievement of multiple EU environmental objectives, the lack of a standardised framework of biodiversity assessment and protection across Member States has led to extensive impairment of riparian areas and frequent stakeholder conflicts. The main objective of RIPARIANET is to leverage the increasing resolution of remote sensing information to provide practitioners with evidence-based guidance and approaches to biodiversity conservation. Key questions include: i) how can we remotely assess riparian integrity and identify areas which provide effective connectivity allowing species biodiversity and ecosystem functions to persist through meta-ecological processes? ii) how can we disentangle the influence of local- and network-scale stressors and processes on riparian biodiversity to better implement river basin management schemes? iii) to what extent do currently existing protected areas in rivers account for the geometry of riparian networks and their multifunctionality? We will address these questions in riparian networks within six river basins in Europe, including Boreal, Continental, Alpine, Temperate and Mediterranean systems. First, we will gather local needs and interests from key stakeholders together with satellite imagery and GIS environmental data for all basins. Then, riparian and river ecosystems functions will be modelled, and ecological hotspots will be identified through a GIS-based multi-criteria, including stakeholders inputs. Then, we will collect in situ data to assess multiple biodiversity and stressors at the local scale and, subsequently, scale-up this information to the network scale using geostatistical tools and advanced modelling. This knowledge will be conveyed to managers at local and EU scales in the form of decision-support tools allowing decision makers to identify protection gaps and ecological hotspots along riparian networks based on multiple biodiversity, functional and connectivity criteria.