1. Connectivity plays a key role in biodiversity conservation as it sustains ecological processes, such as migrations, important for the maintenance of populations. Connectivity is especially relevant for species that rely on different realms during their life cycle or use different realms daily or seasonally (multi‐realm species). However, efforts to address conservation across multiple realms have focused on identifying priority areas for conservation in a single realm (mostly marine) while accounting for threats propagating from other realms or single species needs.
2. Here, we demonstrate how to identify priority areas for conservation across three different realms (freshwater–terrestrial, estuary and marine) for multiple species, including some multi‐realm species, that inhabit or move across the three realms, using the Tagus River (Western Iberian Peninsula), its estuary and nearby marine area as a case study. We integrated multiple types of connectivity in the selection of priority areas for conservation, each of them customised to depict important drivers of movement within each realm and across realms: longitudinal connectivity along rivers or multidimensional connectivity in the estuary and marine realms, guided by currents and depth similarity, respectively. We compared the allocation of priority areas and spatial connectivity achieved under three scenarios: no‐connectivity, within‐realm and cross‐realm connectivity scenarios.
3. There were differences in the spatial allocation of priority areas across scenarios. The most remarkable difference laid on the connectivity achieved under each scenario, which experienced a threefold increase when considering connectivity across realms, compared to solutions that considered only connectivity within each realm independently. This improvement in connectivity was especially marked for species that occur across different realms. There were, however, trade‐offs between this improvement in connectivity and the increase in the number of planning units selected, especially in the estuary.
4. Synthesis and applications. Addressing connectivity across realms deserves special attention when planning for the conservation of multi‐realm species to ensure the adequacy of conservation recommendations to respond to the needs of multi‐realm species. Given the potential trade‐offs between enhanced cross‐realm connectivity and total area needed or internal within‐realm connectivity, consideration of cross‐realm connectivity must be cautiously evaluated and integrated in multi‐realm conservation plans.

中文翻译：

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跨领域的保护规划：增强多领域物种的连通性

1. 连通性在生物多样性保护中起着关键作用，因为它维持着生态过程，例如迁移，这对维持人口至关重要。连通性对于在生命周期中依赖不同领域或每天或季节性使用不同领域的物种（多领域物种）尤其重要。但是，解决跨多个领域的保护问题的工作重点是确定单个领域（主要是海洋）中的优先保护领域，同时考虑到从其他领域或单个物种的需求中传播出来的威胁。
2. 在这里，我们演示了如何使用塔霍河（Westus）在三个不同领域（淡水-陆地，河口和海洋）中识别居住或跨越三个领域的多种物种（包括一些多领域物种）的优先保护区域。以伊比利亚半岛为例，以其河口及附近海域为例。我们在选择优先保护领域时整合了多种类型的连通性，每种类型都进行了定制，以描绘每个领域内和跨领域的重要运动驱动因素：沿河流的纵向连通性或河口和海洋领域的多维连通性，受潮流和水流的引导。深度相似性。我们比较了在以下三种情况下实现的优先区域分配和空间连通性：无连通性，
3. 跨方案的优先领域在空间分配上存在差异。与仅考虑每个领域内的连通性的解决方案相比，在每种情况下实现的连通性最显着的差异在于，考虑跨领域的连通性时，其连通性增长了三倍。对于跨不同领域的物种，连接性的改善尤为明显。但是，在连通性的提高与所选计划单位数量（尤其是河口）的增加之间需要权衡取舍。
4. 综合与应用。规划多领域物种的保护时，应特别注意跨领域的连通性，以确保有足够的养护建议来应对多领域物种的需求。考虑到增强的跨域连接与所需的总面积或内部域内连接之间的潜在权衡，必须谨慎评估跨域连接的考虑并将其纳入多域保护计划中。