GRB 060505 was the first well-known nearby (at redshift 0.089) "hybrid" gamma-ray burst that has a duration longer than 2 seconds but without the association of a supernova down to very stringent limits 1 . The prompt γ−ray flash lasting ∼ 4 sec could consist of an intrinsic short burst and its tail emission 2 , but the sizable temporal lag (∼ 0.35 sec) as well as the environment properties led to the widely-accepted classification of a long duration gammaray burst originated from the collapse of a massive star [3][4][5] . Here for the first time we report the convincing evidence for a thermal-like optical radiation component in the spectral energy distribution of the early afterglow emission. In comparison to AT2017gfo, the thermal radiation is ∼ 2 times brighter and the temperature is comparable at similar epochs. The optical decline is much quicker than that in X-rays, which is also at odds with the fireball afterglow model 6 but quite natural for the presence of a blue kilonova 7,8 . Our finding reveals a neutron star merger origin of the hybrid GRB 060505 and strongly supports the theoretical speculation that some binary neutron stars can merge ultra-quickly (within ∼ 1 Myr) after their formation 9 when the surrounding region is still highly star-forming and the metallicity remains low. Gravitational wave and electromagnetic jointed observations are expected to confirm such scenarios in the near future.

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The land ecosystems of China are estimated to provide an important sink for the increased atmospheric carbon dioxide (CO2), but are undermined by severe ozone (O3) pollution. Mitigation of O3 damage to ecosystems remains a challenge considering that O3 precursors are emitted from a wide range of anthropogenic sectors and O3 formations are also affected by regional transport. Here, we combine chemical transport and dynamic vegetation models to quantify the benefits of sectoral and regional emission controls for the recovery of gross primary productivity (GPP) in the Yangtze River Delta (YRD). For sectoral emission controls, the largest mitigation of O3 damage to GPP in YRD by 3.1±0.4 Gg[C]/day and 2.2±0.2 Gg[C]/day with 50% reductions in the emissions from industry and transportation sectors, respectively. For regional emission controls, reducing 50% anthropogenic emissions outside YRD can mitigate GPP losses by 18.6±3.5 Gg[C]/day, larger than the recovery of 10.1±1.6 Gg[C]/day by the 50% reductions of anthropogenic emissions within YRD. Moreover, summer months, especially July are the best period for GPP recovery from anthropogenic emission controls. Our results highlight the importance of sectoral and regional emission controls to mitigate O3 damage to ecosystem productivities in YRD.