Research Program

Deserts constitute one of the most extended terrestrial environments. They are often considered to be relatively simple ecosystems because they have a unique limiting resource, water, which controls the main productivity and diversity patterns. However, current Ecology shows that in order to explain or to predict these patterns it is necessary to understand the essential influence of climate as well as the direct and indirect effects of trophic relationships established in these communities (e.g., predation, competition, mutualism). Our general project, which takes place in the central region of the Monte desert Argentina, is focused on the study of the composition and structure (i.e., the web of mutual influences) of the plants-seeds-consumers system. It is aimed at understanding in which ways biological interactions are able to mould these natural communities.

Our main research lines address questions about:

phenology and seed production in plants (mainly grasses)

germinative patterns and mechanisms of various forb species

seedling establishment and changes in plant abundance (mainly grasses)

composition and size of soil seed banks and their spatial and temporal dynamics

mechanisms affecting seed permanence in the soil (germination, deep burial, fungal and bacterial attack, consumption by granivorous animals)

the way in which the resource "seeds" (composition, abundance, spatial distribution) affects the behaviour and the abundance of granivores

the way in which granivorous animals affect the composition, abundance and spatial distribution of seed populations (and plants)

the effects of climate (in particular the ENSO phenomenon) on the plants-seeds-consumers system (i.e., on their composition and biological interactions)

This medium and long term project began by carefully studying the ecosystem's natural history so as to plan rigorously further observations and experiments. We currently rely on an empirical and conceptual basis on the characteristics of Monte desert plants and animals. This knowledge lets us formulate plausible mechanismic hypothesis on the top-down and bottom-up effects which can be expected, in a realistic way, from the known trophic relationships web. The complexity underlying the processes under study requires epistemological and methodological attention. This is achieved through a continuous review of assumptions and auxiliary hypothesis (especially of techniques employed for the obtention of data), and the redundancy in the hypothesis testing aimed at identifying robust patterns and explanations (i.e., by using multiple approaches to put the same hypothesis on trial).

Within the framework provided by our research program, we are currently developing projects in four main areas [see: Seeds, Birds, Ants and Epistemology].