Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

Stomata are microscopic pores on the surface of leaves that allow gas exchange between plants and the atmosphere. They are crucial for photosynthesis, but much water vapour is lost by transpiration through leaf stomata. When water is limiting, the stomatal pores adjust to prevent water loss but they can never completely close. We have shown with the model plant Arabidopsis thaliana that reducing the number of stomata can improve plant drought resistance by reducing water loss through transpiration, and help to conserve the amount of water in soils. Conversely, increasing the number of stomata enhances evaporative cooling and would be expected to increase tolerance to heat stress. We would like to apply this strategy to rice so that we can test whether reducing stomatal numbers could improve crop drought and heat stress tolerances, both increasingly major limitations to yield in many parts of the world. We will carry out experiments that aim to re-direct plant water loss to allow enhanced evaporative cooling in reproductive organs without compromising plant drought tolerance, which could be important in future hot and dry environments and at higher atmospheric carbon dioxide concentrations. We have already generated rice plants with genetically reduced or increased stomatal numbers, and propose to test whether growing these under drought or high temperature conditions can improve the total yield of grain harvested. These experiments will be performed on genetically modified (GM) plants but we also propose to isolate and study rice variants in genes that are involved in stomatal development through non-GM techniques, and include these in our studies and test them for drought and heat resistance. We believe that our work will be strategically relevant to the production of rice crops with enhanced drought and heat stress tolerance, and an important step towards improving food security across Asia. Our project directly addresses the following aims of the Newton Rice Research funding scheme: - Greater resilience to abiotic stresses (in this project drought and heat stresses). - Improved resource use efficiency (in this project enhanced water use efficiency). - Novel research tool and technology development (in this project screening and characterisation of germplasm for gene and trait discovery).

This research project focuses on sustainable intensification of agriculture in highly productive peri-urban farming areas in China. This agricultural base is essential to meet China's increasing food production demands but is under pressure from urban pollution inputs, soil and water pollution from farming practices - particularly extensive use of mineral fertilisers and pesticides, and urbanisation. We will quantify the benefits and risks of a substantial step-increase in organic fertiliser application as a means to reduce the use of mineral fertiliser. Our approach is to study the role of soil as a central control point in Earth's Critical Zone (CZ), the thin outer layer of our planet that determines most life-sustaining resources. Our Critical Zone Observatory (CZO) site is the Zhangxi catchment within Ningbo city, a pilot city of rapid urbanization in the Yangtze delta. We will combine controlled manipulation experiments of increased organic fertiliser loading with determination of soil process rates and flux determinations for water, nutrients, contaminants, and greenhouse gas (GHG) emissions across the flux boundaries where the soil profile interfaces with and influences the wider CZ; surface waters and aquifers, vegetation, and the atmosphere. To guide the research design we have identified 3 detailed scientific hypotheses. 1. Replacement of mineral fertiliser use by organic fertiliser will shift the soil food web for N/C cycling from one dominated by bacterial heterotrophic decomposition of soil organic matter (SOM) and bacterial nitrification to produce plant available N and loss of soluble nitrate to drainage waters, to one dominated by heterotrophic fungal decomposition of complex, more persistent forms of OM to low molecular weight organic N forms that are plant available. This change in N source will increase SOM content and improve soil structure through soil aggregate formation. 2. Increased use of organic fertiliser from pig slurry (PS), and wastewater sludge (WS) will lead to increased environmental occurrence of emerging contaminants, particularly antibiotics and growth hormones. Environmental transport, fate and exposure must be determined to quantify development of microbial antibiotic resistance and other environmental and food safety risk, and develop soil and water management practices for risk mitigation. 3. Decreased use of mineral fertilisers and increased use of organic fertilisers will reduce environmental and food safety risks from metals contamination; this is due to lower metal mobility and bioavailability from redox transformations, reduced soil acidification and increased metal complexation on soil organic matter. Our programme of research will conduct the manipulation experiments across nested scales of observation with idealised laboratory microcosm systems, controlled manipulation experiments in field mesocosms, pilot testing of grass buffer strips to reduce the transport of emerging contaminants from the soil to surface waters, and field (~1ha) manipulation experiments. Mechanistic soil process models will be tested, further developed to test the specific hypotheses, and applied to quantify process rates that mediate the landscape scale CZ fluxes as a measure of ecosystem service flows. GIS modelling methods include data from characterisation of a subset of soil properties and process rates at a wider set of locations in the catchment, together with catchment surface water and groundwater monitoring for water and solute flux balances. The GIS model that is developed will identify the geospatial variation in nutrient, contaminant, and GHG sources and sinks and will be used to quantify fluxes at the catchment scale. These results will determine the current baseline of ecosystem service flows and will evaluate scenarios for how these measures of ecosystem services will change with a transition to widespread of organic fertilisers through the farming area of the catchment.

Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.