Title: Investigating the relationships between key environmental and socio-economic variables affecting peatland biogeochemistry and hydrology in the Peruvian Andes.
Lead Supervisor: Prof Nicholas, Branch Department of Geography and Environmental Science, University of Reading
Email: n.p.branch@reading.ac.uk
Co-supervisors: Dr Steve Robinson, Department of Geography and Environmental Science, University of Reading; Prof Joy Singarayer, Department of Meteorology, University of Reading
UKRI funding only covers Home fees which increase annually. International students may still apply to this project, but will be required to meet the difference between the International and Home student fees themselves.
Despite widespread appreciation of the significance of tropical peatlands and their valuable contribution to a range of ecosystem services (e.g., climate regulation, water supply, biodiversity), there remain concerns over their future security. This is evident in the Peruvian Andes; Latin America’s second-largest peatland zone. These peatlands represent important water supplying ecosystems, providing nutritious grazing land for livestock, and irrigation water for agricultural terraces. Their continued functioning is critical both for water security and food production. Despite recognition by Peru’s Glaciers and Ecosystems Research National Institute (INAIGEM) that peatlands provide essential support for a range of ecosystem services, their degradation and loss are accelerating. Several, interrelated factors have been implicated, including unpredictable weather conditions due to climate change, and increasing water demands (mining activities and agro-pastoral farming systems). Given the interdependence between agricultural practices and water availability, we need to better understand the functioning of these peatland ecosystems in order to influence agendas for their management. Critically, we need to establish the extent of biogeochemical degradation caused by water extraction, pollution (e.g., agrochemicals) and overgrazing. Secondly, we need to ascertain the primary sources of water recharging the peatlands, including (in the absence of glacial meltwater), groundwater, rainfall, surface runoff and water management infrastructure.
The research will seek to address this challenge with a geographical focus on the regions of Apurimac (Chicha-Soras Valley) and Ayacucho (Sondondo Valley) in south-central Peru. These regions are representative of upland peatlands in the Peruvian Andes not having access to glacier meltwater. Given that the biogeochemistry and hydrology of peatlands are symptoms of interacting climate, ecological, and management pressures, the following key research questions will be addressed:
1) What are the key spatial characteristics of peatland biogeochemical degradation and what are the primary causes?
2) What are the main water sources sustaining peatlands in the Puna (4000+m asl), Quechuan (2500-3500m asl) and Suni (3500-4000m asl) ecological zones?
3) What are the best methodologies and metrics for national monitoring of peatland biogeochemistry and ecohydrological conditions?
The research will enhance our understanding of the relationships among key environmental and socio-economic variables affecting peatland ecosystems. We will use a novel mixed method approach involving field and laboratory measurements.
- Eight peatlands have been identified as suitable case studies. Six of them have significant evidence of water extraction and grazing, and are located proximal to terrace agriculture in the Quechuan and Suni (2500-4000m asl) ecological zones, whilst the remainder present case studies with minimal modern human interference enabling baseline comparisons of peatland ecosystem degradation and hydrology. The peatlands will permit spatial, field-based characterisation of peatland extent, microtopography, depth and surface vegetation composition. Dip-wells will be installed to record hydrological variability together with cost-effective meteorological instrumentation and loggers suitable for remote locations to record weather conditions over the life of the project. In situ measurements will be combined with high-spatial resolution blended meteorological products (Peruvian met services – SENAMHI) to better characterize local weather and climate variability. Peat core samples collected from each site will enable laboratory-based analysis of the physio-chemical biological properties of the peat, especially ash content, moisture content, bulk density, C/N ratios, δ¹³C and δ¹⁵N isotope ratios, Fe speciation (redox proxy), organic carbon, humification, geochemistry and functional group chemistry (ICP-OES, FTIR), porosity (SEM) and plant macro-remains [to address research question 1].
- Within the drainage basin of the eight peatlands, we will employ a sampling strategy for in-situ water testing (e.g., pH, EC, DO, redox potential, turbidity and depth). Samples will also be collected of surface water, throughflow/interflow, peat porewater, and groundwater for major ions (e.g., Cl⁻, SO₄²⁻, NO₃⁻, PO₄³⁻, HCO₃⁻; Ca²⁺, Mg²⁺, Na⁺, K⁺, Fe2+ and Fe3+) using IC, ICP-OES and UV-Vis spectrophotometry, as well as dissolved nutrients (e.g., DOC, nitrate, ammonium, phosphorus, nitrogen) using dry combustion/NDIR detection and segmented flow/spectrophotometry techniques. [to address research question 2].
- Conduct interviews and workshops with farmers and NGOs to ascertain the precise nature of land-use and legislation for the protection of peatlands. Together with (1) and (2) these will be used to co-produce a toolkit for monitoring peatlands and knowledge transfer protocols with a range of stakeholders, which can be applied to other Peruvian peatlands. [to address research question 3].
Training opportunities:
This is an excellent opportunity to develop a wide range of skills in an area of key importance to the Peruvian Andes in maintaining peatland ecosystem services. The project would enable the student to pursue opportunities in environmental science post PhD. Key skills include field-based peatland survey and sampling, and participatory action research (PAR) to collect social science data in Peru, and laboratory analysis of the physical, chemical and biological properties of peat. Our Peruvian project partner (NGO Asociación Andina Cusichaca) will offer support with the PAR to enable the student to receive in-depth training.
Student profile:
This project would be suitable for a student with a degree in environmental science or physical geography, and a keen interest in peatlands. Experience of field methods commonly used in peatland science would be desirable, as well as the laboratory analysis of the physical, chemical or biological properties of peat. In addition, some experience of working with NGO practitioners would be desirable but not essential. UKRI funding only covers Home fees which increase annually. International students may still apply to this project, but will be required to meet the difference between the International and Home student fees themselves.
