Behind the scenes of the Maestre lab (VI): Juan Gaitán on ecosystem structure and functioning in Patagonian rangelands

We continue with the series of posts describing the “behind the scenes” of the research presented in the articles we publish (you can find the previous posts of this series here, here, here, here and here). In this case we will talk about a paper just published as part of the special feature on grassland/woodland transitions in  Journal of Ecology entitled “Vegetation structure is as important as climate for explaining ecosystem function across Patagonian rangelands”, led by our graduate student Juan Gaitán. Juan is a researcher at INTA (Argentina´s national institute for research on agriculture and livestock production) in San Carlos de Bariloche, Argentina. This article is also related to another paper led by Juan that has just been published in Biology Letters (“Plant species richness and shrub cover attenuate drought effects on ecosystem functioning across Patagonian rangelands”).

Juan Gaitán, the lead author of this paper

These are the Q & A for Juan:

What is this paper about?

In this paper we evaluated the relative importance of abiotic and biotic as drivers of regional variations in ecosystem functional attributes. Specifically, we assessed how temperature and both the amount and seasonal distribution of precipitation can interact with the cover of grasses and shrubs and plant species richness to influence surrogates of above-ground primary productivity, precipitation use efficiency and precipitation marginal response. For doing this, we used 311 sites across a broad natural gradient in Patagonian rangelands (south Argentina).

Map with the location of the sites surveyed in this work

What are the key messages of this article?

Our study shows that vegetation structural attributes explained a significant and unique portion of the variability found in ecosystem functioning at the regional scale, which is as important as that explained by climate. Our results have important implications for the management and conservation of rangelands in the context of ongoing climate change. Through appropriate grazing management, allowing maintaining and enhancing vegetation cover and species richness (particularly of grasses) could offset or mitigate the adverse effects of climate change on ecosystem functioning in these ecosystems.

How did you come up with the idea of conducting this study?

I could say it that all started 10 years ago, on a very cold winter day in the INTA´s Experimental Ranch of Rio Mayo (Chubut province). A group of rangeland researchers from INTA met there to start designing a system for long-term monitoring of desertification and global climate change in Patagonian rangelands; this was the beginning of the MARAS monitoring system (Spanish acronym of Environment Monitoring of Arid and Semiarid Regions). We discussed for several years what ecosystem attributes we should measure and how to measure them. In 2008 we began to install and survey the network of permanent MARAS plots, which nowadays is formed by more than 300 sites measured using the same standardized protocol. This database allowed us to explore several questions related to the structure and functioning of arid and semiarid ecosystems. In 2013, I visited for 3 months the Maestre Lab and I had the opportunity to discuss with Fernando the first ideas of this article. Our main motivation was to better understand the role of structural attributes of vegetation as drivers of ecosystem functioning at the regional scale. Several studies have explored the importance of climate as a major driver of ecosystem functioning at this scale, but there is currently a lack of research evaluating how plant richness and cover modulate controls on ecosystem functioning by climate at the regional scale. And the MARAS database was certainly highly suitable to explore these questions!

What have you enjoyed the most during the “life cycle” of this article (from its conception to its publication)?

I have really enjoyed all the stages involved in the making of this article, but if I have to choose one, I would certainly select the fieldwork. Since I started working in the MARAS project I had the opportunity to know many very beautiful places of Patagonia and share many fun times with my colleagues. As you can see in the pictures below, many of the sites we surveyed are gorgeous!

What have been the major difficulties you have encountered when conducting the research reflected in this article?

Many people worked to collect the MARAS data in the field. Sorting, cleaning and digitizing all the field data was a hughe and tedious job, and I spent countless hours doing this in Excel! Learning about Structural Equation Modelling was also a challenging task for me, but I think the hardest part was writing the article. My native language is Spanish and this is one of the first articles I have written in English, so this was very hard for me. But with this article I learned a lot about scientific writing and I hope to continue improving this important skill for every scientist.

Publishing today is really hard, how has been your experience with this publication?

When Fernando suggested me to send the manuscript to Journal of Ecology,  I thought it would be a hard process. I confirmed this when less than a week after sending the manuscript the manuscript was rejected by Scott Wilson (the Associate Editor responsible) and Richard Bardgett (one of Journal of Ecology’s Editors). They raised some some significant doubts about our manuscript which led to its rejection, but at the same time they were very positive about our study and found that it had considerable potential for the journal. Thus, they gave us the possibility of resubmit the paper. This encouraged us to write a new version of the manuscript. Comments and suggestion of two reviewers were very constructive and after three rounds of revisions the manuscript really improved. Finally, I would like to thank the co-authors of this article for all their support during all this process.