Simulated Small Scale Disturbances Increase Decomposition Rates and Facilitates Invasive Species Encroachment in a High Elevation Tropical Andean Peatland
Simulated Small Scale Disturbances Increase Decomposition Rates and Facilitates Invasive Species Encroachment in a High Elevation Tropical Andean Peatland
复制标题
模拟小规模扰动会增加高海拔热带安第斯泥炭地的分解率并促进入侵物种的入侵
DOI：
10.1111/btp.12191
复制
发表时间：
2015
期刊：
影响因子：
2.1
通讯作者：
J. C. Benavides
中科院分区：
文献类型：
--
作者：
J. Urbina;J. C. Benavides
热带高山泥炭地是重要的碳库，是当地水文循环的重要组成部分。在高海拔泥炭地，分解速度慢是因为营养贫乏的底物不易腐烂。Páramo泥炭地生态系统对农业活动增加的养分添加和身体干扰的反应尚不清楚。在这里，我们在哥伦比亚中央安第斯山脉的泥炭沼泽地进行了为期两年的施肥和身体干扰实验。我们假设，施肥和物理干扰将通过增加分解来降低泥炭储存有机质的能力，维管植物将取代泥炭藻类成为优势植物群。我们通过添加粪便作为肥料来模拟牛的活动，并将身体干扰作为践踏牛的代理。物种组成与干扰强度成正比。在任何干扰处理下，泥炭盖度均减小。非本地牧草通常出现在牛场，通过增加化肥或身体干扰来入侵处理。总体而言，施肥处理的地上植物生物量增加了一倍，这表明植物生物量的生产是有限的。与对照组相比，受扰处理组的分解率增加了两倍。这降低了泥炭地储存有机物的能力。安第斯泥炭地是珍贵的生态资产；然而，我们的结果表明，埃尔莫罗帕拉莫泥炭地在小范围干扰后的短时间内经历了更快的腐解率。这对这些泥炭地提供的生态服务产生了深远的影响。
Tropical alpine peatlands are important carbon reservoirs and are a critical component of local hydrological cycles. In high elevation peatlands slow decomposition rates result from a nutrient‐poor substrate resistant to decay. The responses of páramo peatland ecosystems to increased nutrient additions and physical disturbance due to agricultural activities are unknown. Here, we conducted a two‐year fertilization and physical disturbance experiment in a Sphagnum—dominated peatland in the Central Andes of Colombia. We hypothesized that fertilization and physical disturbance will diminish the ability of the peat to store organic matter by increasing decomposition and that vascular plants will displace Sphagnum as the dominant plant group. We simulated cattle activity by adding manure as a fertilizer and physical disturbance as a proxy for cattle trampling. Species composition varied in proportion to the intensity of disturbance. Sphagnum cover was reduced under any disturbance treatment. Non‐native grasses usually found in cattle pastures invaded treatments with fertilizer additions or physical disturbance. Overall aboveground plant biomass doubled in fertilized treatments, suggesting that plant biomass production was nutrient limited. Decomposition rates tripled in disturbed treatments as compared to controls. This reduces the ability of the peatland to store organic matter. Andean peatlands are prized ecological assets; however, our results show that the El Morro páramo peatland experienced increased decomposition rates over short time periods after small‐scale disturbances. This created profound consequences for the ecological services offered by these peatlands.