A historical baseline study of the páramo of Antisana in the Ecuadorian Andes including the impacts of burning, grazing and trampling

ABSTRACT

Background

We report the vegetation at 4050–4600 m in 1960 on the western slopes of Antisana, Ecuador, decades before burning and grazing were prohibited. Aim: To provide a baseline against which new surveys could be compared to evaluate conservation efforts.

Methods

We (a) ordinated grassland types and derived communities using constancy values of species in typical stands, (b) recorded evidence of community dynamics, (c) recorded the composition of communities occupying smaller areas than the grassy páramo, and (d) recorded inhibition and facilitation of other species by Azorella cushions.

Results

Short-turf grassland had replaced much tall-tussock grassland as a result of grazing and burning. Intense trampling had resulted in dominance by an introduced annual grass. Disturbance of most tall-tussock grassland on lava flows had left gaps made by fire or rabbit-scratching; these were invaded by distinctive sets of species. Azonal communities, changed much less by humans, contained 63% of 155 native species of vascular plant encountered, and 68% of 65 mosses. Younger cushions of Azorella impacted negatively on associated species but older cushions had facilitative effects.

Conclusions

Our study provides an adequate record against which to determine the extent and nature of changes in the vegetation since farming of livestock ceased.

KEYWORDS:

• Azorella cushion
• gap plants
• facilitation
• páramo mosses
• plant refugia
• species distributions
• succession on glacial moraines
• vegetation dynamics

Acknowledgements

We thank other members of the expedition (M.R. Emerson and the late Drs R.H. Johnson and T.C. Whitmore for support in the field, and R.H. Johnson for taking all the photographs), the late Mr R. Delgado for permission to work on his estate, and Empresa Electrica Ltda of Quito for permission to use their building on Antisana as our base. The late Sir George Taylor gave permission to T.D.P. to work up our collections at Kew, the late Dr B. Ström (Göteborg) gave invaluable advice on the taxonomy and nomenclature of páramo plants, the late E.B. Bartram identified the mosses, the late Dr P.W. James the lichens. Prof. A.M. Cleef provided invaluable literature on Colombian and northern Ecuadorean páramos, the late Dr C.J. Burrows made very helpful comments on early drafts of the paper, Prof. Z. Kikvidze advised on literature about positive effects of some plants on others, Dr J. Bishop and Prof. R. del Moral on nitrogen-fixing plants on moraines in temperate regions of North America, Drs P. Bellingham, A. Fajardo and F. Piper on such plants in the Southern Hemisphere, and Prof. C. Körner on relevant experiments; Dr E. Tanner provided invaluable logistical support. Dr E. Buscado carried out the non-metric multidimensional scaling ordination. Miss S.M. Bishop drew the first versions of the Figures. We acknowledge the freely available rain gauge data provided on the Fondo para la Protección del Agua (FONAG) website: http://sedc.fonag.org.ec/. and the ORE data provided by the Service National d’observation SNO GLACIOCLIM. Drs L. Ruedas, T. Lee and S. Borneo helped greatly with information about mammals in the study area. We thank Laszlo Nagy and two anonymous reviewers for their advice which led to major improvements. Our approach to the dynamics of the grassy páramo was inspired by the teaching and publications of the late Dr A.S. Watt.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplemental data

Supplemental data for this article can be accessed here.

Additional information

Funding

We thank many people for material aid in 1960, particularly the managers of the Mount Everest Foundation, the Percy Sladen Memorial Fund and the Royal Society Government Grant-in-Aid for financial assistance. Sebastián Páez-Bimos acknowledges support from the research cooperation project ‘Linking Global Change with Soil and Water Conservation in the High Andes’ (PáramoSus) funded by the Académie de Recherche et Enseignement Supérieur de la Fédération Wallonie-Bruxelles (ARES) Belgium.

Notes on contributors

Peter J. Grubb

Peter J. Grubb has published on a variety of ecological problems in a range of vegetation types from tropical to cool temperate, from rain forest to semi-desert, and from the lowlands to the alpine zone.

J. Robert Lloyd

J. Robert Lloyd was for years a schoolteacher of biology with very wide interests, including ecology on which he published a textbook; he has been heavily involved in the practical issues of conservation locally.

Terence D. Pennington

Terence D. Pennington has worked on the taxonomy and floristics of Amazonian and Andean trees, specialising in Meliaceae, Sapotaceae, Inga and Sloanea, and in agroforestry systems and land reclamation based on Inga.

Sebastián Páez-Bimos

Sebastián Páez-Bimos is currently studying the effect of landscape on water and geochemical fluxes in the high Andes.