Final answer:
Distance Decay is the term that describes the effect of distance on cultural interactions, stating that the interaction between two places declines as the distance between them increases.
Step-by-step explanation:
The term that describes the effect of distance on cultural interactions, stating that the interaction between two places declines as the distance between them increases, is known as Distance Decay. This concept is the result of the friction of distance, which creates patterns on the landscape characterized by a tendency of objects, ideas, and behaviors to decrease in intensity or regularity as they move further from their original source. According to geographer Waldo Tobler, the idea that near things are more related than distant things is known as Tobler's First Law of Geography.