Final answer:
Cold temperatures are the characteristic that slows down nutrient cycling in boreal forests.
Step-by-step explanation:
The characteristic that slows down nutrient cycling in boreal forests is cold temperatures. Boreal forests are found in high latitudes where the temperatures are typically low, resulting in slow decomposition rates and microbial activity. This limits the breakdown of organic matter and slows down nutrient availability for plants.
Learn more about Nutrient cycling in boreal forests