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全球各地的城市已经用白色LED灯取代了橙色高压钠（HPS）街灯，承诺能节省能源。然而，这种“升级”却加剧了光污染，并对生态系统造成了伤害，因为我们优化的是每瓦流明，而不是系统的健康。 天空变得越来越亮尽管功耗降低，卫星数据显示全球的天空亮度每年增加约2%（《科学进展》，2016年）。这是为什么呢？ 白色LED灯（通常为4000K–5000K）发出强烈的蓝光，其在大气中的散射程度是HPS琥珀光的三倍。防护不良的灯具向上泄漏光线——即使是旧灯具的“改装”套件也常常缺乏适当的光学设计。较低的运营成本鼓励过度照明（杰文斯悖论）。真实的生态危害经过同行评审的研究证实： 昆虫聚集在富含蓝光的LED灯下→局部种群崩溃（《生物学快报》，2018年）。迁徙鸟类因天空亮度的干扰而与建筑物发生碰撞。蝙蝠、青蛙及其他夜行性物种的觅食和繁殖受到干扰。美国医学协会甚至在2016年警告称，高色温街灯抑制褪黑激素的分泌并增加眩光——降低夜间安全性。 更好的解决方案这并不是反对LED，而是支持系统思维。解决方案是存在的： 使用≤2700K的LED灯（蓝光较少，视觉舒适度更好） 强制使用全切割灯具（零向上光） 通过运动感应或定时在午夜后调暗灯光 像图森和戴维斯这样的城市证明，您可以在节能的同时保护夜空。

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Cities worldwide have replaced orange high-pressure sodium (HPS) streetlights with white LEDs—promising energy savings. But this “upgrade” is worsening light pollution and harming ecosystems, because we optimized for lumens per watt, not system health.The Sky Is Getting Brighter Despite lower power use, satellite data shows global skyglow is increasing by ~2% yearly (Science Advances, 2016). Why?White LEDs (often 4000K–5000K) emit intense blue light, which scatters 3× more in the atmosphere than HPS’s amber glow. Poorly shielded fixtures leak upward—even “retrofit” kits in old housings often lack proper optics. Cheaper operating costs encourage over-lighting (Jevons paradox). Real Ecological Harm Peer-reviewed studies confirm:Insects swarm blue-rich LEDs → local population collapse (Biol. Lett., 2018). Migratory birds collide with buildings due to disorientation from skyglow. Bats, frogs, and other nocturnal species show disrupted foraging and reproduction. The AMA even warned in 2016 that high-CCT streetlights suppress melatonin and increase glare—reducing nighttime safety.A Better Path This isn’t anti-LED—it’s pro-systems thinking. Solutions exist:Use ≤2700K LEDs (less blue, better visual comfort)Mandate full-cutoff fixtures (zero uplight)Dim lights after midnight via motion or schedulingCities like Tucson and Davis prove you can cut energy and protect the night.

LED路灯正在破坏生态系统——一种系统性失败