Nuclear Techniques for a Better Understanding of the Impact of Climate Change on Soil Erosion in Upland Agro-Ecosystems - D1.50.17


Background:

The latest report of 2014 from the Intergovernmental Panel on Climate Change (IPCC) emphasizes the expected impact of climate change, especially in upland areas. The effects of climate change are expected to worsen, bringing more extreme weather events such as droughts, floods, heat waves, and unpredictable rainfall distribution, all of which threaten food security and could make agricultural production in uplands difficult, if not impossible.

Nuclear Techniques for a Better Understanding of the Impact of Climate Change on Soil Erosion in Upland Agro-ecosystems Climate change effects are highly visible in upland areas also designated as "less favoured areas" due to their challenging physical conditions (terrain, topography and climate) and farmers’ high vulnerability and exposure to climate change as compared to lowland farming communities. The document Agenda 21 of the United Nations (UNCED) emphasized that in the 21st century, the focus of agricultural development will have to shift from developing green revolution technologies for lowland areas, to finding ways of improving the productivity of agriculture in marginal areas.

Upland agro-ecosystems will face three major challenges related to food security and climate change in the coming decades: (1) increasing food production while improving, protecting and optimising soil and water use efficiency, (2) adapting to climate change impacts on soil and water resources, and (3) contributing to climate change mitigation. Adapting to climate change in the uplands requires agricultural soil and water management practices that make agricultural production systems resilient to drought, floods and land degradation, to enhance the conservation of the natural resource base for sustainable upland farming.

Integrated isotopic approaches can help develop strategies for targeted and effective soil management practices to control soil degradation in upland agroecosystems.

Objective:

This CRP aims to (i) develop combinations of nuclear techniques to assess impacts of changes on soil erosion, and (ii) distinguish and apportion impacts of climate variability and agricultural management on soil erosion in upland agro-ecosystems.

Nuclear techniques including Fallout Radionuclides (FRNs) such as caesium-137 (137Cs), lead-210 (210Pb), beryllium-7 (7Be) and plutonium-239 and 240 (239+240Pu), Compound-Specific Stable Isotope (CSSI) techniques based on the measurement of carbon-13 (13C) natural abundance signatures of specific organic compounds (i.e. fatty acid) and Cosmic Ray Soil Moisture Neutron Probe (CRNP) will be used to fulfil the CRP objectives.

Participants:

Twelve countries participate in this CRP: four research contract holders from China, Iran - Islamic Republic of, Madagascar and Morocco, seven agreement holders from Canada, Italy, United Kingdom, United States of America, Spain and Switzerland, and two technical contractors from Austria and New Zealand.

Activities:

This CRP was formulated on the basis of the recommendations of a consultants’ meeting held at IAEA headquarters, Vienna from 8–12 December 2014. The First Research Coordination Meeting was held on 25-29 July 2016 in Vienna, Austria) and the second RCM took place at the Centre National de l’Energie, des Sciences et des Techniques Nucléaires (CNESTEN) in Rabat, Morocco, from 16 to 20 April 2018.

This CRP is in the beginning of its third year of implementation and major efforts will be performed to test the 137Cs resampling approach which appears to be one of the most suitable technique to fulfil the second challenging objective of the CRP.

The third RCM of the CRP D1.50.17 is expected to be organized in Vienna at the end of third or beginning of fourth quarter 2019.

Key results:

During the first two years of its implementation, significant progress related to the first objective of the CRP was made in developing and refining fallout radionuclides (FRN) and CSSI techniques to deepen our understanding of erosion processes affecting upland agro-ecosystems.

(a) The main milestone of the first-year activity of the CRP was the development of the new and unique FRN conversion model MODERN.

(b) During the second year, significant progress was made in testing and validating the use of plutonium isotopes (239+240Pu) as soil tracer versus other more mature FRN techniques (e.g. 137Cs and 210Pbex) under different agro-environments (i.e. Switzerland, South Korea, Austria).

Since its start in March 2016, the CRP team has already published 14 peer-reviewed publications acknowledging the CRP D1.50.17 and we are in the process of developing guidelines for supporting its two scientific objectives.

Project Officer:

Lionel Mabit and Lee Heng