旅游区游憩活动对鸟类扩散种子的影响

鸟类在植物种子传播中扮演着重要的角色。为了研究旅游活动对鸟类传播种子的影响,在兴凯湖自然保护区游憩区和非游憩区选择黄檗(Phellodendron amurense Rupr.)树种作为观测对象进行对比研究。结果显示,游人活动高峰时段游憩区鸟的取食行为发生了明显改变,取食鸟的物种丰富度、取食频度、取食时间以及种子取食量均显著减少。观察发现,游人活动干扰是导致鸟的取食行为发生改变的根本原因。取食行为的改变,减少了种子的扩散机会,进一步导致了幼苗更新量的减少以及相对较短的扩散距离。此外,对幼苗更新格局的检验发现,游憩区幼苗在空间分布上明显偏向景观内部。产生该结果的原因与鸟的飞离路径有关,来自景观外部的游人干扰压力可能是导致鸟的飞行路径发生改变的主要原因。结果表明,旅游活动可能通过干扰动植物关系对植物产生连锁影响。

Effects of recreational activities on bird-mediated seed dispersal in tourism areas

Birds play a key role in seed dispersal of plants. To investigate influences of tourism activities on bird-mediated seed dispersal, we conducted a comparison study by selecting Phellodendron amurense Rupr. individuals for observation at a recreation site and non-recreation site at the Khanka Lake Nature Reserve. The results showed that bird-feeding behaviors were significantly altered at the recreation site during rush hours with intensive visitation. Bird species richness, feeding frequency, feeding time, and predation numbers all markedly decreased. It was found that recreational disturbances were the fundamental factors leading to the changes in bird feeding behaviors. Changes in feeding behaviors of birds reduced opportunities for seed dispersal, further resulting in the reduction of recruits and shorter distances of dispersal. In addition, seedlings were mostly established inside the landscape at the recreation site, which was linked to changes in the paths birds flew caused by recreational disturbances. The results suggested that recreational activities could cause ripple effects on plants through disturbing animal-plant relationships.