Red Soil CZ: From Natural to Anthropogenic Evolution of Red Soil and its Impact on Ecosystem Function in the Critical Zone
Red soils cover 20% of each of China and India, the most populated countries on earth, as well as large areas of developing countries in southeast Asia, Africa and South America. They form in sub-tropical climates where excessive leaching from rainwater has produced an infertile, unstable soil that is very vulnerable to mismanagement, climate change and pollution such as acid rain. In China, red soils support about 40% of the population, made possible through the intensive use of fertilisers to boost crop yields. This farming system is unsustainable; fertilisers reaching groundwater, freshwater and the atmosphere pose a significant environmental threat, and soil degradation through intensive cultivation can result in tens of tonnes of soil being eroded each year from a hectare of land into water courses during the intensive monsoonal, spring rains. Red soil management for agriculture affects local farmers who depend on them for their livelihood, the surrounding population who need them for food, China because of dependence for national food production and globally because of the area red soils covers, their importance for food production and the large environmental footprint.
We are using the established Sunjia Critical Zone Observatory (CZO) near Yangling China to gain a much better understanding of red soils and their interaction with the environment. Although extensive research has studied red soils, particularly related to management for agricultural sustainability, the integrated effects of various affected aspects of the critical zone, as well as the wider environmental impacts are poorly understood. We adopt a critical zone approach, to reach beyond soil processes to encompass the atmosphere above, geology and groundwater below, surrounding freshwater and vegetation. The new science generated in this project, particularly the modelling outputs, provides valuable data for policy decisions in China about the management of red soils. We provide training to project partners in interdisciplinary science that is essential to CZO research and will benefit the research capabilities of the Chinese team. Moreover, we bring new skills to the Chinese team in terrestrial modelling. Coupled with our intended outcome of more sustainable food production from red soils, our training and government agency engagement ensures delivery of OECD Official Development Assistance from this project.
The scientific aim of this project is to bridge scales to disentangle how soil weathering, hydrology, biology, erosion and soil fertility of red soils interact under contrasting land management, and influence the resilience of the red soil critical zone from such perturbations in the quality and quantity of water inputs. Equally important, it is our aim to translate our scientific findings to produce outputs that inform land users and policy makers to lead to the sustainable management of red soils.
1. To enhance resource use efficiency (water and nutrients) for crop production on red soils from the understanding of cycling and flows to the wider environment.
2. To mitigate soil erosion, fertility losses and crop abiotic stress from a changing climate by improving the resilience of red soils to external stresses.
3. To use information systems and modelling to upscale the proposed CZO science so that evidence based policy decisions can improve the sustainable use of red soils in China.
Working in and around the Sunjia Critical Zone Observatory. a) taking measurements, b) at the inlet and c) the bounded erosion plots.
- University of Aberdeen
- University of York
- Chinese Academy of Science (CAS) Institute of Soil Science
- Guangdong Institute of Eco-Environmental and Soil Sciences
- University of Science and Technology of China