Ecologists investigating long-term changes in a forest near an industrial center find decreased biodiversity among species, along with decreased growth and reproductive health. Which air pollutant would the ecologists most likely suspect is responsible

particulate matter

Explanation:

The most likely pollutant that is capable of causing a decrease in a forest's biodiversity, as well as decreased growth and reproductive health of individual plants within the forest, would be particulate matters.

Particulate matters in the atmosphere generally get deposited on the organs of plants such as leaves, stems, and flowers. When this happens, they block the various openings of the organs such as stomata, lenticels, and hydathodes.

The blockage of these openings results in several physiological processes such as photosynthesis and gaseous exchange being negatively affected leading to decreased growth, reproductive health, or sometimes, outright death of plants.

The death of many individual plants in a forest eventually leads to a decrease in the diversity of the forest.

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