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

欧洲已承诺对包括30%的陆地和海洋在内的高级生态系统进行保护。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面积严重有限。河岸带是水生和陆地生态系统之间的自然过渡带，对区域生物多样性贡献巨大，并提供多种生态系统功能和服务。由于这一点和它们的分支几何形状，河岸网络形成了一个巨大的“蓝绿动脉”系统，尽管覆盖了盆地相对较小的区域，但它在物理上和功能上连接了海拔梯度上的多个生态系统。因此，我们认为，开发能够优化自然河流-河岸网络空间保护优先级的方法是欧盟生物多样性保护的一个旗舰例子。尽管河岸地带的完整性是实现多个欧盟环境目标的基础，但缺乏跨成员国的生物多样性评估和保护的标准化框架导致了河岸地区的广泛损害和频繁的利益相关者冲突。RIPARIANET的主要目标是利用不断提高的遥感信息分辨率，为从业者提供基于证据的生物多样性保护指导和方法。关键问题包括：i)我们如何远程评估河岸完整性并确定提供有效连通性的区域，使物种多样性和生态系统功能通过元生态过程持续存在？Ii)我们如何理清局域和网络尺度的压力源和过程对河岸生物多样性的影响，从而更好地实施流域管理方案？Iii)现有的河流保护区在多大程度上反映了河岸网络的几何形状及其多功能性？我们将在欧洲六个河流流域的河岸网络中解决这些问题，包括北方、大陆、高山、温带和地中海系统。首先，我们将收集主要利益相关者的当地需求和利益，以及所有流域的卫星图像和GIS环境数据。然后，将建立河岸和河流生态系统功能模型，并通过基于gis的多标准（包括利益相关者的输入）识别生态热点。然后，我们将收集原位数据，以评估本地尺度上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尺度。这些知识将以决策支持工具的形式传达给地方和欧盟层面的管理者，使决策者能够根据多种生物多样性、功能和连通性标准，确定河岸网络的保护缺口和生态热点。

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.