Abstract

ZIMMER, Anaïs et al. Characterizing the upward migration of high-Andean plant communities under the effects of global warming with early post-glacial chronosequences. Ecología en Bolivia [online]. 2014, vol.49, n.3, pp.27-41. ISSN 1605-2528.

Accelerated glacial retreat consecutive to global warming represents a challenging situation for alpine plant communities, especially high-Andean wetland communities (bofedales). Actually, such migration is expected to require much more time than the time frame available between glacial retreat and the development of proper environmental parameters for colonization (especially soil weathering/formation). Accordingly it is expected that new alpine communities will suffer a strong re-organization, with impoverished high Andean species pool. This contribution provides and discusses methods to examine the modalities of primary succession following accelerated glacial recession in the Tropical Andes. We suggest using four post-glacial chronosequences (0-38 yrs after glacial retreat) to infer early patterns of primary succession after glacial retreat under the effects of rapid warming. Vegetation can be examined with plots 1 m² in size, using at least 15 repetitions within each deglaciation band (four for each chronosequence). We describe a series of biotic and abiotic measurements designed to estimate the effects of (1) dispersal limitation of each plant species, (2) abiotic stress (temperature, water, wind), and (3) the presence/absence of nurse organisms such as plants and the soil biological crust, on the earlier steps of primary succession. Testing these methods in the context of the project BIOTHAW allowed us to discuss the relevance of each of them and to propose complementary methods worth being tested in future studies with a similar objective.

Keywords : Climate change; High-Andean ecosystems; Nurse organisms; Primary succession; Soil biological crust.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )