Maria do Carmo Oliveira Jorge

Slope Processes, Mass Movement and Soil Erosion: A Review

Abstract Soil erosion and land degradation are global problems and pose major issues in many countries. Both soil erosion and mass movement are two forms of land degradation and humans play important roles in these geomorphological processes. This paper reviews slope processes associated with mass movement and soil erosion and contributory factors, including physical and human agents. Acting together, these cause diverse geomorphological features. Slope processes are illustrated by reference to case studies from Brazil and UK. The causes and impacts of erosion are discussed, along with appropriate remedial bioengineering methods and the potential of the measures to prevent these types of environmental degradation. Although there are several agents of erosion, water is the most important one. Cultivation can promote soil erosion, due to ploughing and harvesting, which moves soil down slopes. Soil erosion and mass movement data would inform the viability of soil conservation practices. Integrated management of drainage basins offers a promising way forward for effective soil conservation and soil remedial bioengineering in Brazil and UK.

Mapping of heavy metal contamination in alluvial soils of the Middle Nile Delta of Egypt

Areas contaminated by heavy metals were identified in the El-Gharbia Governorate (District) of Egypt. Identification used remote sensing and Geographical Information Systems (GIS) as the main research tools. Digital Elevation Models (DEM), Landsat 8 and contour maps were used to map physiographic units. Nine soil profiles were sampled in different physiographic units in the study area. Geochemical analysis of the 33 soil samples was conducted using X-ray fluorescence spectrometry (XRF). Vanadium (V), nickel (Ni), chromium (Cr), copper (Cu) and zinc (Zn) concentrations were measured. V, Ni and Cr concentrations exceeded recommended safety values in all horizons of the soil profiles, while Cu had a variable distribution. Zn concentrations slightly exceeded recommended concentration limits. Concentrations were mapped in each physiographic unit using the inverse distance weighted (IDW) function of Arc-GIS 10.1 software. Pollution levels were closely associated with industry and urban areas.

Gully Erosion and Land Degradation in Brazil: A Case Study from São Luís Municipality, Maranhão State

Soil erosion and land degradation are global problems and pose major problems in Brazil, which is characterized by a great diversity of soil types. This chapter discusses gully erosion and land degradation in Brazil, outlining a case study from Sao Luis City, Maranhao State. This diversity is related to a wide variety of landforms, climates, parent materials, vegetation cover and biota and is influenced by land use and management. Therefore, a brief description of different types of land degradation, mainly gully erosion and mass movements, is presented, and illustrative photographs are presented. These hazards affect both urban and rural areas within the extensive national territory (8,547,403 km2). Consequently, these problems have serious environmental impacts and pose socio-economic challenges.