Canopy‐forming algae play a key role in temperate coastal ecosystems sustaining complex habitats that provide food and refuge for rich associated biotic communities. These macroalgae are in decline in many coastal areas, where overgrazing by herbivores can lead to the loss of these highly structured and diverse habitats toward less complex sea urchin barren grounds. Once established, low productive barren grounds are considered stable states maintained by several positive feedback mechanisms that prevent the recovery of marine forests. To revert this global decline, restoration efforts and measures are being encouraged by EU regulations and local actions. Here, we tested the success of active revegetation techniques as a tool to promote functional and productive Treptacantha elegans forests in sea urchin barren grounds under different restoration strategies (active, and combined active with passive strategies). Active revegetation was performed in 6 barren grounds, 3 located inside a Mediterranean No‐Take marine reserve (active and passive strategy) and 3 outside (active strategy alone), following a three‐step protocol: (1) sea urchin population eradication, (2) seeding with Treptacantha elegans, and (3) enhancement of T. elegans recruitment. Revegetation success was assessed 1 year later in the six barren grounds, but was only achieved after combining active with passive restoration strategies. Our results encourage revegetation of barren grounds to shift from less productive habitats to complex T. elegans forests, highlight the potential of the combined passive and active restoration strategies, as well as the important role of marine reserves not only in conservation but also in ecological restoration.

中文翻译：

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从海洋荒漠到藻类床：线虫的植被重新生长，使No-Take海洋保护区内外稳定的退化生态系统逆转

形成冠层的藻类在温带沿海生态系统中扮演着关键角色，该生态系统维持着复杂的生境，为丰富的相关生物群落提供食物和庇护所。这些大型藻类在许多沿海地区都在减少，草食动物过度放牧会导致这些高度结构化和多样化的栖息地向不太复杂的海胆贫瘠的土地流失。一旦建立起来，低生产力的贫瘠土地就被认为是由防止海洋森林恢复的几种积极反馈机制维持的稳定状态。为了扭转这一全球下降趋势，欧盟法规和地方行动正在鼓励恢复工作和采取措施。在这里，我们测试了主动植被再造技术作为促进功能性和生产力线虫的工具的成功海胆荒地中的森林在不同的恢复策略下（主动，主动和被动结合）。遵循3个步骤，在6个贫瘠的土地上进行了主动植被恢复，其中3个位于地中海禁捕性海洋保护区内（主动和被动策略），外部3个（仅主动策略）：( 1）消灭海胆种群，（ 2）播种线虫，和（3）增强线虫募集。一年后，在六个贫瘠的土地上评估了植被恢复的成功，但是只有在将主动与被动恢复策略相​​结合之后才能实现。我们的结果鼓励了荒地重新植被，从生产力较低的栖息地转变为复杂的线虫。 森林强调了被动和主动恢复策略相​​结合的潜力，以及海洋保护区不仅在保护方面而且在生态恢复中的重要作用。