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

欧洲承诺对高端生态系统进行保护，将30%的陆地和海洋包括在内。然而，由于历史上对自然资产的过度开采，可用于保护生物多样性的面积严重有限。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，这些动脉在物理上和功能上通过海拔梯度连接多个生态系统，尽管覆盖的面积相对较小。因此，我们认为，开发能够优化自然溪流-河岸网络空间保护优先顺序的方法是欧盟生物多样性保护的旗舰范例。尽管河岸带的完整性是实现欧盟多项环境目标的基础，但由于成员国缺乏生物多样性评估和保护的标准化框架，导致河岸区遭到广泛破坏，利益攸关方冲突频发。RIPARIANET的主要目标是利用遥感信息日益提高的分辨率，为从业人员提供基于证据的指导和养护生物多样性的方法。关键问题包括：i)我们如何才能远程评估河岸的完整性，并确定提供有效连通性的区域，从而使物种生物多样性和生态系统功能在元生态过程中持续存在？二)我们如何才能理清地方和网络规模的压力来源和过程对河岸生物多样性的影响，以便更好地实施河流流域管理计划？三)目前河流中现有的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？我们将在欧洲六个河流流域的河岸网络中解决这些问题，包括北冰洋、大陆、阿尔卑斯山、温带和地中海水系。首先，我们将收集关键利益攸关方的当地需求和利益，以及所有流域的卫星图像和地理信息系统环境数据。然后，将对河岸和河流生态系统功能进行建模，并将通过基于地理信息系统的多标准(包括利益相关者的投入)来识别生态热点。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，并随后利用地质统计工具和高级建模将这些信息扩大到网络规模。这些知识将以决策支持工具的形式传达给当地和欧盟级别的管理人员，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河岸网络沿线的保护差距和生态热点。

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.