Climatic drivers of Sphagnum species distributions

Frontiers of Biogeography

article

Charles Campbell¹  Gustaf Granath²  Hakan Rydin² 

[1] Greensway AB;Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University

关键词: climate;    degree days;    GBIF data;    peat mosses;    peatlands;    precipitation;    species distribution models;   

DOI  :  10.21425/F5FBG51146

学科分类：社会科学、人文和艺术（综合）

来源: International Biogeography Society

【 摘 要 】

Peat mosses (genus Sphagnum) dominate most Northern mires and show distinct distributional limits in Europe despite having efficient dispersal and few dispersal barriers. This pattern indicates that Sphagnum species distributions are strongly linked to climate. Sphagnum-dominated mires have been the largest terrestrial carbon sinks in Europe over the last few millennia. Understanding the climatic drivers of Sphagnum species distributions is important for predicting the future functionality of peatlands. We used MaxEnt, with biologically relevant climatic variables, to model and clarify the current distributions of 45 Sphagnum0.8). Large pixels (100 and 200 km) resulted in loss of detail, but smaller pixels (10-50 km) performed well across fit measurements. Projected distributions at the 50 × 50 km resolution showed the largest resemblance to published distribution maps. Suitable climate for many Sphagnum species was associated with the northern, western and mountainous parts of Europe. We found that annual water balance was an important indicator of Sphagnum presence. Limits in relation to annual water balance were the same as reported by bioclimatic peatland models from North America. Most Sphagnum species were limited to annual degree-days between -5000 °C y-1 and 5000 °C y-1. Seasonality in both climate variables separated species, with degree-day seasonality having a stronger influence than water balance seasonality. High degree-day seasonality as a consequence of cold temperature sets a northern distribution limit to some species. The results suggest that the future of Sphagnum diversity in Europe is most strongly dependent on changes in water availability and in seasonal temperature variation.

【 授权许可】

CC BY