Stephen H. Hallett

Soil Atlas of Africa

of water, nutrients and as a medium for growing. Soil stores, filters, buffers and transforms substances that are introduced into the environment. This capability is crucial in producing and protecting water supplies and for regulating greenhouse gases. Soil is a provider of raw materials. Soil is also an incredible habitat and gene pool. Soil is a fundamental component of our landscape and cultural heritage. The properties of soil vary tremendously from region to region. Soils under tropical rainforests are vulnerable to erosion and nutrient depletion if the vegetation cover is removed. Oasis regions in deserts and the Sahel show how seemingly infertile soils can be cultivated in the presence of water. The wetlands of Congo and other major African systems are stores of soil organic carbon and important wildlife habitats. The black, clay-rich soils of the Nile Valley in Sudan are rich in nutrients but difficult to cultivate when very wet or very dry. Soils with high salt levels are not suitable for the cultivation of crops but may support a unique plant community. AFRICA SOIL ATLAS OF

Driving Forces of Land-Use Change in a Cultural Landscape of Spain

The aim of this chapter is to examine the processes of change in land cover and land use over the last 44 years, at regional scale, in a traditional, rural south-eastern Spanish catchment. Land use has changed dramatically over recent decades throughout the Mediterranean. Much of this change has been driven by shifts in agricultural and socioeconomic policy. Analysis of aerial photography for the Marina Baixa catchment has revealed a significant decline in traditional agriculture and conversion to forestry or intensive croplands. The consequences of economic globalisation are reflected here in a shift from traditional to intensive agriculture and in human migration from rural to urban areas, as well as in the development of tourism. Land-use changes are correlated with socioeconomic structural forces in order to demonstrate how these changes affect the basic resources of the area and to provide a clearer understanding of possible future trends.

Compilation of an accumulated temperature database for use in an environmental information system

Abstract Accumulated Temperature (AT) is the integrated excess or deficiency of temperature about a fixed datum. It is a parameter obtained from temperature data, which can be used in models of crop growth. Accumulated temperature values can therefore be used by crop agronomists to model regional differences, for instance across Britain, and may prove increasingly important for assessing the impact of climate change. Previous studies have shown how knowing the response of a crop to a given AT regime allows the use of AT maps to demark areas suitable for growth. Thus, zones of suitability may be delineated on a national or regional basis for temperature sensitive crops such as maize. This work was undertaken to produce a flexible system for the generation of AT datasets for any specified threshold. These datasets can be used for comparison with AT data used in other parts of the world, and as a fundamental input to the assessment of land suitability. A software suite, ‘ATGen’ 1 , has been developed for accumulating temperature data above and below user-selected temperature values for specified time periods.

Soil legacy data rescue via GlobalSoilMap and other international and national initiatives

Legacy soil data have been produced over 70 years in nearly all countries of the world. Unfortunately, data, information and knowledge are still currently fragmented and at risk of getting lost if they remain in a paper format. To process this legacy data into consistent, spatially explicit and continuous global soil information, data are being rescued and compiled into databases. Thousands of soil survey reports and maps have been scanned and made available online. The soil profile data reported by these data sources have been captured and compiled into databases. The total number of soil profiles rescued in the selected countries is about 800,000. Currently, data for 117, 000 profiles are compiled and harmonized according to GlobalSoilMap specifications in a world level database (WoSIS). The results presented at the country level are likely to be an underestimate. The majority of soil data is still not rescued and this effort should be pursued. The data have been used to produce soil property maps. We discuss the pro and cons of top-down and bottom-up approaches to produce such maps and we stress their complementarity. We give examples of success stories. The first global soil property maps using rescued data were produced by a top-down approach and were released at a limited resolution of 1km in 2014, followed by an update at a resolution of 250m in 2017. By the end of 2020, we aim to deliver the first worldwide product that fully meets the GlobalSoilMap specifications.

Soil geohazard mapping for improved asset management of UK local roads

Unclassified roads comprise 60 % of the road network in the United Kingdom (UK). The resilience of this locally important network is declining. It is considered by the Institution of Civil Engineers to be “at risk” and is ranked 26th in the world. Many factors contribute to the degradation and ultimate failure of particular road sections. However, several UK local authorities have identified that in drought conditions, road sections founded upon shrink–swell susceptible clay soils undergo significant deterioration compared with sections on non-susceptible soils. This arises from the local road network having little, if any, structural foundations. Consequently, droughts in East Anglia have resulted in millions of pounds of damage, leading authorities to seek emergency governmental funding. This paper assesses the use of soil-related geohazard assessments in providing soil-informed maintenance strategies for the asset management of the locally important road network of the UK. A case study draws upon the UK administrative county of Lincolnshire, where road assessment data have been analysed against mapped clay-subsidence risk. This reveals a statistically significant relationship between road condition and susceptible clay soils. Furthermore, incorporation of UKCP09 future climate projections within the geohazard models has highlighted roads likely to be at future risk of clay-related subsidence.

Monitoring the response of roads and railways to seasonal soil movement with persistent scatterers interferometry over six UK sites

Road and rail networks provide critical support for society, yet they can be degraded by seasonal soil movements. Currently, few transport network operators monitor small-scale soil movement, but understanding the conditions contributing to infrastructure failure can improve network resilience. Persistent Scatterers Interferometry (PSI) is a remote sensing technique offering the potential for near real-time ground movement monitoring over wide areas. This study tests the use of PSI for monitoring the response of major roads, minor roads, and railways to ground movement across six study sites in England, using Sentinel 1 data in VV polarisation in ascending orbit. Some soils are more stable than others—a national soil map was used to quantify the relationships between infrastructure movement and major soil groups. Vertical movement of transport infrastructure is a function of engineering design, soil properties, and traffic loading. Roads and railways built on soil groups prone to seasonal water-logging (Ground-water Gley soils, Surface-water Gley soils, Pelosols, and Brown soils) demonstrated seasonal subsidence and heave, associated with an increased risk of infrastructure degradation. Roads and railways over Podzolic soils demonstrated relative stability. Railways on Peat soils exhibited the most extreme continual subsidence of up to 7.5 mm year−1. Limitations of this study include the short observation period (~13 months, due to satellite data availability) and the regional scale of the soil map—mapping units contain multiple soil types with different ground movement potentials. Future use of a higher resolution soil map over a longer period will advance this research. Nevertheless, this study demonstrates the viability of PSI as a technique for measuring both seasonal soil-related ground movement and the associated impacts on road and rail infrastructure.

Soil-Net: development and impact of innovative, open, online soil science educational resources

Despite recognition of soil as a major global natural resource and longstanding policy recognition of its importance for understanding environmental systems and stewardship in a rapidly urbanizing world, soil science has been under-represented in teaching National Curriculum in UK schools. Alongside concerns about declining student participation in science education, a key challenge is how to effectively engage students and address inadequacies in soil education. A UK government-funded initiative led to Soil-Net, an innovative, open, online soil educational website resource to support school curricula. Following a decade of online availability, this paper analyses website data on the adoption, use and impact of Soil-Net 2006-2016. First, data analysis based on geo-identification of over a million and a half users revealed patterns of adoption and usage by territory. Though originally targeted in the UK, Soil-Net is now being used worldwide in 223 countries and territories. Second, analysis of student scores on soil science knowledge quizzes available to be used alongside school education and curricula assessments, provided evidence of student learning supported by Soil-Net resources. Third, analysis based on user ratings and qualitative feedback revealed good satisfaction ratings by primary and secondary school students, teachers and parents. Usage data analysis offers an initial evaluation of Soil-Net, although further research is required to evaluate support for curricula and student learning. Next steps include development of website resources using innovative pedagogies to ensure applicability and sustainability, and research to further evaluate how Soil-Net is used in schools, and its contribution to soil science teaching and learning.

A review of potential methods for monitoring rangeland degradation in Libya

Natural and human factors exert a profound impact on the degradation of rangelands, human effects being the most significant factor in increasing the severity of deterioration. This occurs through agricultural expansion at the expense of rangelands, and with the number of domestic and wildlife animals exceeding the natural carrying capacity. This raises concerns about the ongoing sustainability of these land resources, as well as the sustainability of traditional pastoral land practices. Rangelands require effective management, which is dependent upon accurate and timely monitoring data to support the assessment of rangeland deterioration. Natural rangelands provide one of the significant pillars of support for the Libyan national economy. Despite the important role of rangeland in Libya from both economic and environmental perspectives, the vegetation cover of Libyan rangeland has changed adversely qualitatively and quantitatively over the past four decades.Ground-based observation methods are widely used to assess rangeland degradation in Libya. However, multi-temporal observations are often not integrated nor repeatable, making it difficult for rangeland managers to detect degradation consistently. Field study costs are also significantly high in comparison with their accuracy and reliability, both in terms of the time and resources required. Remote-sensing approaches offer the advantage of spanning large geographical areas with multiple spatial, spectral and temporal resolutions. These data can play a significant role in rangeland monitoring, permitting observation, monitoring and prediction of vegetation changes, productivity assessment, fire extent, vegetation and soil moisture measurement and quantifying the proliferation of invasive plant species. This paper reviews the factors causing rangeland degradation in Libya, identifying appropriate remote-sensing methods that can be used to implement appropriate monitoring procedures.

Towards evaluation design for smart city development

Abstract Smart city developments integrate digital, human and physical systems in the built environment. With growing urbanization and widespread developments, identifying suitable evaluation methodologies is important. Case-study research across five UK cities ‒ Birmingham, Bristol, Manchester, Milton Keynes and Peterborough ‒ revealed that city evaluation approaches were principally project-focused with city-level evaluation plans at early stages. Key challenges centred on selecting suitable evaluation methodologies to evidence urban value and outcomes, addressing city authority requirements. Recommendations for evaluation design draw on urban studies and measurement frameworks, capitalizing on big data opportunities and developing appropriate, valid, credible integrative approaches across projects, programmes and city-level developments.

Soil moisture content measurement using optical fiber long period gratings

The use of an optical fibre long period grating (LPG) as a soil moisture sensor is reported. Characterization of the device in both clay and sandy soils revealed a sensitivity to moisture levels in the range 10–50%, and the results were compared with the output from a Theta probe, the standard soil moisture sensor, which measures the impedance of the soil.