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How did the Chicxulub impact affect Earth’s food chains at the end of the Cretaceous?

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Cretaceous paleogeography — Cretaceous Period Distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins during the late Cretaceous Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.

The Chicxulub impact significantly disrupted Earth’s food chains at the end of the Cretaceous Period by triggering a global environmental collapse.123

The collision ejected massive quantities of rock debris, dust, and sulfur into the atmosphere, creating a global cloud that blocked sunlight for months or even years. This lack of solar radiation caused photosynthesis to cease, leading to the widespread death of green plants on land and plankton in the oceans. Because these organisms formed the base of the food web, their decline resulted in the starvation and extinction of animals higher up the food chain, including non-avian dinosaurs and various marine reptiles.1234

Additionally, the impact caused immediate, localized devastation through tsunamis, wildfires, and extreme heat, while the release of sulfurous minerals likely led to acid rain and ocean acidification. These combined stressors caused the collapse of entire ecosystems, ultimately resulting in the extinction of approximately 80 percent of all species.2413