Answer:
combustion of manure piles in hot weather
Step-by-step explanation:
A manure piles are heap of animal waste or excreta mainly the waste from horse manure and the bedding which is stored to decompose and reduce in bulk.
Particulate matter is a mixture of small particles as well as liquid droplets that causes pollution and is harmful to health.
Burning of manure piles can cause to fly the dust and the dirt in the animal manure in the air and it leads to particulate matter suspended in the air.