遊憩容許量為戶外遊憩研究與經營者長期探討的議題，本研究應用視覺評估法探討步道上遊客人數與擁擠感受間之關係，研究地點為陽明山國家公園二子坪遊憩區之步道，本研究在前景、中景、遠景配置不同數量的遊客與行進方向，共模擬148張相片於現地進行問卷調查，請受訪者對於照片遊客人數以-4（一點也不擁擠）到+4（非常擁擠）進行擁擠感受評估。研究結果顯示步道上的遊客人數對擁擠感受有顯著正向影響效果，且人物位置對擁擠感受有顯著影響，距離愈近，受測者愈容易感受到擁擠，行進方向則不具有顯著的影響效果。此外，到訪目的在於欣賞自然、第一次來、或造訪頻率較高的受訪者，其擁擠感受較高。

For many years, both researchers and recreational outdoor recreation managers have been concerned with carrying capacity. This study investigates the relationship between crowding perception and the number of visitors on a hiking trail using the visual approach. The study area was the hiking trail in Erzihping Recreation Area at the Yangmingshan National Park. A total of 148 photographs with different numbers of visitors in the foreground, middle ground, and background, and direction of movement were simulated. A visitor survey was conducted on-site and visitors were asked to evaluate their perceptions of crowding in the photographs on a scale from -4 (not crowded at all) to +4 (very crowded). The results showed that the number of visitors on the trail significantly and positively influenced crowding perception. The positions of visitors on the trail also significantly influenced crowding perception—the closer the visitors are positioned in the photograph, the higher the crowding perceived. However, the direction of movement was not found to have a significant influence on crowding perception. It was also found that more crowding was perceived for visitors with the purpose of enjoying the natural scenery, first time visitors, and visitors who had a higher visiting frequency.