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A unique facility for engineering and biological research has been established with the aim of improving fundamental understanding of the effects of climate change on slopes. This paper describes the building and monitoring of a full-scale embankment representative of UK infrastructure, the planting and monitoring of representative vegetation, and the construction of a system of sprinklers and covers to control climate. A summary of the results of the first experiments simulating predicted future UK climate and the response of the embankment is also presented. The information that has begun to be gathered is providing data related to the failure modes anticipated as a result of climate change and hence on the sustainability of UK infrastructure slopes.

Tropical forests are global climate regulators through their interaction with hydrological and biogeochemical cycles. Despite extensive research on deforestation in South America and its global impact, the role of the largely intact Guiana Shield forests, north of the Amazon, has not yet been considered as part of this climate system. We use a regional climate model with a realistic deforestation scenario to test the impact of deforestation in the Guiana Shield on climate throughout South America. We show that replacing ∼28% of the current Guiana Shield rainforest with savannah leads to multi-scale impacts across South America, through vegetation-land-atmosphere interactions that disrupt the initial phase of two major 'atmospheric rivers': the Caribbean low-level Jet and the South American low-level jet (SALLJ). Our climate simulations suggest that following deforestation, locally, precipitation and runoff would more than double in lowland forests, whilst mean annual temperatures would increase by up to 2.2• C in savannahs. Regionally, significant wetting is simulated in northern South America (April−September) and the western Amazon (October-March), while temperatures increase up to 2• C in central and eastern Amazon, causing more dry months in up to 64% of the Amazon basin. Reduction of moisture transfer by the SALLJ of 2.2% of total annual flow causes noticeable and highly diverse spatial changes in simulated monthly rainfall in la plata basin (LPB). These results highlight the potential consequences of land cover change in a sensitive hot-spot with hydro-climatic impacts 1000 km west and 4000 km south. Such multi-scale perturbations can severely impact biodiversity and ecosystem services across South America, including agriculture in LPB. Recognition of the far field effects of localised deforestation in key areas is urgently needed to improve development plans for a sustainable future. Significance statementThe Guiana Shield, at the northern boundary of Amazonia, is located at the start of two atmospheric rivers which carry moisture across South America. We show that deforesting less than a third of the Guiana Shield, in areas currently under threat from mining, logging and agricultural activities, could result in significant changes in the water cycle across the continent. This includes large variations in temperature and precipitation affecting areas 4000 km away, impacting ecosystems and economies, with consequences for society. The study demonstrates how land-use change, even if small in spatial scale, but occurring in particularly sensitive hot-spots, can alter the flow of atmospheric rivers, with large consequences. This pan-continental cascade must be considered when designing trans-national management plans for a sustainable future.

Question: How can long-term monitoring of hydrological and ecological parameters support management strategies aimed towards wetland restoration and re-creation in a complex hydrological system? Location: Newham Bog National Nature Reserve, Northumberland, UK, a site with a long history of active management, and recorded as drought-sensitive over the last 100 years. Methods: Water level readings are correlated with longer-term hydrological databases, and these data related to vegetation data collected intermittently over a 12 year period. Two analyses are undertaken: (1) a composite DCA analysis of 1993 and 2002 survey data to assess plant community transitions within the wetland and over time, and (2) analysis of recent vegetation data to explore wider vegetation gradients. This allows (3) communities to be classified using NVC classes and (4) integrated with revised Ellenberg F-values. Results: Drought impact and subsequent hydrological recovery over a 22-year period are quantified. Vegetation data display strong moisture and successional gradients. Analysis shows a shift from grassland communities toward mire communities across much of the site. Conclusion: The site is regionally unique in that it has a detailed long-term monitoring record. Hydrological data and vegetation survey have allowed the impact of the most recent 'groundwater' drought (1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997) to be quantified. This information on system resilience, combined with eco-hydrological analyses of plant community-water regime/quality relationships, provide a basis for recommendations concerning conservation and restoration.

Abstract:A large rainfall simulator (LRS, area 970 m 2 ) is being used to measure flow, sediment and contaminant runoff from a pasture hillslope in the North Island of New Zealand. Results from a winter experiment corresponding to a 1 in 8 year storm were used to calibrate a complex, physically based hydrological model (SHETRAN, Ewen et al., 2002). The ability of SHETRAN to reproduce firstly the observed runoff hydrograph and secondly the soil moisture response, was assessed. Surface runoff was widely distributed over the simulator plot but was not uniform because of uneven topography and possibly because of spatial variations in soil properties. Most model parameters were determined from field measurements, but two (vertical hydraulic conductivity and surface friction) were 'calibrated' by matching the observed and predicted runoff hydrograph. The calibrated model had a coefficient of determination (R 2 ) of 98%, and reproduced accurately the shape of the hydrograph and the total volume of runoff. The model predicted soil moisture that matched TDR probe measurements within the calibration uncertainties, at one location, and underestimated the reduction in soil moisture following the end of rain, possibly indicating that the calibrated value of vertical hydraulic conductivity was too low. This study assumed no-flux boundary conditions under and around the LRS, and while this approximation may be acceptable when modelling a single storm, vertical and downslope drainage will need to be quantified in future longer-term applications. From both field data and model simulations, it was concluded that surface runoff occurred principally as a result of the infiltration excess (IE) mechanism. Saturation excess (SE) and variable source area (VSA) were rejected as the principal generation mechanisms.