PLANT COMMUNITY RESPONSES TO SIMULATED ENVIRONMENTAL CHANGE AT A HIGH ARCTIC POLAR SEMI-DESERT

作者：Clare H. Robinson, Philip A. Wookey, J. A. Lee, Terry V. Callaghan, Malcolm C. Press · 发表于：Ecology · 年份：1998 · DOI：10.1890/0012-9658(1998)079[0856:pcrtse]2.0.co;2 · 被引用次数：190 · 研究领域：Climate change and permafrost、Lichen and fungal ecology、Polar Research and Ecology

Impacts of climate change were simulated over five summer seasons in a high arctic polar semi-desert at Ny Ålesund, Svalbard, by using polythene tents to increase temperature, and by increasing precipitation and soil nutrient (NPK) availability. The effects of these treatments on vegetation cover were assessed at the start of the 1991, 1993, and 1995 field seasons, and at peak biomass in the same years. Over the first season of the experiment (1991), changes in percentage total living vegetation cover were significantly greater, and changes in dead vegetation cover significantly lower, in the tented treatments. In subsequent seasons, changes in total living cover were also greater under treatments simulating climate change, although the significant factors and interactions were year-specific. Between years, at both the early and mid-season sampling periods, the fertilizer application had the strongest effect on changes in plant cover, significantly decreasing cover of living Dryas octopetala, Saxifraga oppositifolia, and bare ground between 1991 and 1995, while increasing cover of bryophytes, Salix polaris, Polygonum viviparum, and total dead vegetation. Although cover of D. octopetala was greater during the first three years of fertilizer addition, marked winter injury occurred in this species on fertilized plots during winter 1993–1994. This resulted in reductions in total live cover and D. octopetala cover and an increase in total dead cover (by up to 22%) in watered and f...