Overview

Studies on carbon fluxes (CO2 and CH4) and forest biomass along the Amazonian-Andean slopes located north of the equator are non-existent. The majority of research efforts have been focused in locations south of the equator, making difficult to account for regional comparison of carbon fluxes and forest biomass at both sides of the equator. The importance of lowland tropical rainforest in carbon dynamics and forest biomass is relatively well studied (Araujo-Murakami et al., 2014; Malhi et al., 2015). The neighbouring area of the Amazonian-Andean slopes have recently received some attention and initial data on plant diversity and forest biomass have been produced. However, these initial studies have also been focused on sites located south of the equator e.g. Bolivia, Peru and Ecuador ( Girardin et al., 2014). A similar study north of the equator has yet to be conducted. The extensive band of Amazon-Andean forest on both sides of the equator form part of the orographic encroachment contributes to the control of easterly air masses and precipitation which promotes high biodiversity (Ter Steege et al., 2003). The region is, in several parts, under threat by extensive agriculture and yet little is known about carbon fluxes, forest biomass and species composition.

Recent research conducted in the Peruvian Andes has demonstrated some minor variation in the above ground net primary productivity (NPP) along the altitudinal gradient as a result of elevation and variation in respiration within different forest types (Marthews et al., 2012). In South America, a strong seasonal variation in rainfall is driven by the mean annual position of the intertropical convergence zone (ITCZ) that creates a warmer effect towards the northern hemisphere causing a strong energy flux across the equator (Schneider et al., 2012). Such ITCZ-driven seasonality may contribute to the generation of feedbacks in carbon pools and climate at regional scales (e.g. Amazon basin) especially in anomalous dry periods and during strong El Niño events (Doughty et al., 2015). Therefore, in order to have a more accurate estimation the regional carbon fluxes (CO2 and CH4) along Amazon-Andean gradients in South America, there is a need for new data to complete models of carbon fluxes and biomass estimations for the complete Amazonian-Andean area from Peru-to-Colombia.

 

Altitudinal gradient at higher elevation (3200 m asl) in the Colombian Andes.

Methodology

Fieldwork will be conducted in the Colombian Andes in collaboration with colleagues from the Nacional University in Colombia. In this study the student will collect primary data on carbon fluxes along an altitudinal gradient from the Colombian Ande aiming to develop a model of the variability of carbon fluxes under potential climate change scenarios. A large proportion of the project will involve gathering field data and modelling. Carbon flux measurements will be conducted using portable soil gas flux systems. Portable chambers will be deployed along an altitudinal gradient to capture the representative range of local environmental conditions. Gas samples will be measured directly in the field. For the estimation of below ground carbon and fluxes, core cylinders will be used. Modelling of carbon fluxes under different scenarios of climate change will be conducted using the JULES model (Senior et al., 2016).

 

Training and Skills

CENTA students are required to complete 45 days training throughout their PhD including a 10 day placement. In the first year, students will be trained as a single cohort on environmental science, research methods and core skills. Throughout the PhD, training will progress from core skills sets to master classes specific to CENTA research themes.

 The student will obtain training on the carbon cycle, carbon fluxes, modeling using JULES and the interpretation of data. In addition, he or she will receive additional training on sampling during the field work.

Timeline

Year 1: Initial training in using chambers for studying greenhouse gases, sample collection, and training in multivariate analysis and programing/modelling in JULES. Learning about Colombian geography, biogeography of Neotropical plants and learning about environmental gradients.

Year 2: Field sampling in the Colombian Andes, exploration of gathered data and presentation of initial results.

Year 3: Comparison of research outputs against other carbon fluxes from the South American Andes.  Presentation of results at international conferences is anticipated from year 2 onwards.

Partners and collaboration (including CASE)

Dr. Berrio and Dr. Kaduk have very strong track records in ecology and climate change at low latitudes and analysis of environmental data. Both are involved in a vibrant and diverse PhD supervision program. Dr Berrio has 21 years of experience researching Neotropical ecosystems and palaeoclimate change. Dr. Kaduk researches ecosystem trace gas fluxes and energy exchange. He has 15 years experience in eddy covariance measurements and 25 years in carbon cycle and ecosystem modelling with particular focus on ecophysiology. He has supervised 7 PhD students to completion. Dr. Parra, is an experienced Colombian ecologist, and investigates plant diversity along spatial and environmental gradients of Andean forests. He works at the Instituto de Ciencias Naturales (ICN) fat the Nacional University of Colombia. He will be the local contact point from which field work will be conducted. 

Further Details

Contact: Dr. Juan Carlos Berrio jcb34@le.ac.uk