Governments recently adopted new global targets to halt and reverse the loss of biodiversity. It is therefore crucial to understand the outcomes of conservation actions. We conducted a global meta-analysis of 186 studies (including 665 trials) that measured biodiversity over time and compared outcomes under conservation action with a suitable counterfactual of no action. We find that in two-thirds of cases, conservation either improved the state of biodiversity or at least slowed declines. Specifically, we find that interventions targeted at species and ecosystems, such as invasive species control, habitat loss reduction and restoration, protected areas, and sustainable management, are highly effective and have large effect sizes. This provides the strongest evidence to date that conservation actions are successful but require transformational scaling up to meet global targets.

中文翻译：

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保护行动的积极影响

各国政府最近通过了新的全球目标来阻止和扭转生物多样性的丧失。因此，了解保护行动的结果至关重要。我们对 186 项研究（包括 665 项试验）进行了全球荟萃分析，这些研究测量了一段时间内的生物多样性，并将保护行动的结果与适当的不采取行动的反事实进行了比较。我们发现，在三分之二的情况下，保护要么改善了生物多样性的状况，要么至少减缓了衰退。具体来说，我们发现针对物种和生态系统的干预措施，例如入侵物种控制、减少和恢复栖息地丧失、保护区和可持续管理，是非常有效的，并且具有很大的效果。这提供了迄今为止最有力的证据，表明保护行动是成功的，但需要转型扩大规模才能实现全球目标。