We quantitatively assess the impacts of Downgrading Protected Areas (PAD) on biodiversity in the U.S. Results show that PAD events significantly reduce biodiversity. The proximity to PAD events decreases the biodiversity (abundance) by 26.0 % within 50 km compared with records of species further away from the PAD events. We observe an overall 32.3 % decrease in abundance after those nearest PAD events are enacted. Abundance declines more in organisms living in contact with water and non-mammals. Species abundance is more sensitive to the negative impacts in areas where the decisions of PAD events were later reversed, as well as in areas close to protected areas belonging to the International Union for Conservation of Nature (IUCN) category. The enacted PAD events between the period 1903 to 2018 in the U.S. led to economic losses of approximately $689.95 million due to the decrease in abundance. Our results contribute to the understanding on the impact of environmental interventions such as PAD events on broadscale biodiversity change and provide important implications on biodiversity conservation policies.

中文翻译：

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降级保护区 （PAD） 对生物多样性的影响


我们定量评估了降级保护区 （PAD） 对美国生物多样性的影响。结果表明，PAD 事件显着降低了生物多样性。与远离 PAD 事件的物种记录相比，靠近 PAD 事件使 50 公里内的生物多样性（丰度）减少了 26.0%。我们观察到，在那些最近的 PAD 事件颁布后，丰度总体下降了 32.3%。在与水接触的生物和非哺乳动物中，丰度下降得更多。物种丰度对 PAD 事件决定后来被推翻的地区以及属于国际自然保护联盟 （IUCN） 类别的保护区附近的地区对负面影响更为敏感。1903 年至 2018 年期间在美国颁布的 PAD 事件由于丰度减少导致约 6.8995 亿美元的经济损失。我们的结果有助于理解环境干预措施（如 PAD 事件）对大规模生物多样性变化的影响，并为生物多样性保护政策提供重要意义。