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Although there have been extensive studies on the hydrological and erosional impacts of logging, relatively little is known about the impacts of conversion into agricultural plantation (namely rubber and oil palm). Furthermore, studies on morphological impacts, sediment-bound chemistry and forensic attribution of deposited sediment to their respective sources are scarcer. This chapter introduces the potential for using the multi-proxy sediment fingerprinting technique in this context. Featuring pilot projects in two major flood-prone river systems in Malaysia, the studies explore application of geochemistry-based sediment source ascription. The geochemical signatures of sediment mixtures on floodplains were compared to sediments from upstream source tributaries. The tributaries were hypothesised to have different geochemical signatures in response to dominant land management. The first case study took place in the Segama River system (4,023 km²) of Sabah, Malaysian Borneo where a mixture of primary forest, logged-forests and oil palm plantations were predominant. The second case study was in the Kelantan River Basin (13,100 km²) with two major tributaries (Galas River and Lebir River) where logged-forests and rubber and oil palm plantations are dominant land-uses. Both case studies demonstrated the applicability of this method in ascribing floodplain deposited sediment to their respective upstream sources. Preliminary results showed that trace elements associated with fertilisers (e.g. copper and vanadium) contribute to agricultural catchment signatures. Alkaline and alkaline-earth elements were linked to recently established oil palm plantations due to soil turnover. Mixing model outputs showed that contributions from smaller, more severely disturbed catchment are higher than those from larger but milder disturbed catchments. This method capitalises on flood events to counter its adverse impacts by identifying high-priority sediment source areas for efficient and effective management.

Southeast Asia has been actively undergoing land conversion into agricultural lands over past few decades. This creates the challenges to the nation in dealing with the non-point source pollutants in many fluvial systems, thus requiring an effective approach in sediment source apportionment for an appropriate target mitigation procedure. The trace element property from different source points was used for catchment classification of Galas River. Sediment sample collection was carried out at the sources and sink areas of the catchment system. Fine sediment was analysed using X-ray fluorescence to obtain elemental composition followed by the statistical test and numerical model. Out of 83 elements, 12 elements (Mn, Ca, Cr, Ga, Dy Hf, Y, V, Th, Pb, Zn and Sr) have been selected as best tracer signatures. The solver model has indicated Pergau River as the major sediment contributor to this large catchment system. The model output could directly be proportional with the land-use practice, indicating excessive terrestrial alteration has taken place within the sites for agricultural plantation purposes. Thus, this highly recommends for the decision-making use to the targeted areas to overcome the serious sedimentation issues caused by the tillage operation in affected stream points and to improve the watershed quality.

The purpose of this research is to determine the major environmental impacts and, especially, to evaluate the geochemical characteristics of water of the lakes formed in abandoned quarries of ornamental rock of the Campo Belo Metamorphic Complex.

To do so, 12 quarries were chosen to be studied. They were mapped in a detail scale and their rocks were described and sampled for petrography analysis. Whenever present, the lakes were evaluated too. In situ measurements included pH, Eh, conductivity, resistivity, total dissolved solids and temperature. Water samples were collected to determine alkalinity, sulfates, chlorates, turbidity, suspended sediments and the concentrations of major and trace elements using the ICP‐OES.

Abandoned open‐pit mining operations have resulted in the creation of numerous pit lakes. About 90 per cent of the quarries visited and studied were abandoned or interdicted by environmental organs, what will probably lead to its subsequent abandonment. The quarries Borges and Gêmeos were two quarries of the abandoned quarries in the region, which has a lake formed in its trench. Gêmeos and Borges pit lakes analytical data shows clear correlation between the chemical compositions of the solute and the geological characteristics of the quarries. In spite of the differences found, the results showed a relatively quality water according to Brazilian legislation control values.

This was the first study done of pit lakes formed in abandoned ornamental rock quarries of Campo Belo Metamorphic Complex/Minas Gerais – Brazil. This research provides a better understanding of the gneisses pit lakes hydrogeochemistry, a subject neglected in scientific literature.

Human actions on natural ecosystems have not only jeopardized human well-being but also threatened the existence of other species. On the other hand, the benefits resulting from a greater integration between the logic of nature and human occupations have been seen as motivating factors for the prevention and mitigation of environmental impacts in landscape planning, since it provides human well-being through the grant of resources, regulation of the environment and socio-cultural services called ecosystem services. This article highlights the relevance of using ecosystem integrity indicators related to the functioning of ecological support processes for landscape planning.

The research used the photosynthetic performance of vegetation through carbon fluxes in the landscape, defining areas where different approaches to green infrastructure can be applied, gaining over the majority of work in this area, in which low degrees of objectivity on measurement and consequent ecological recovery still prevail. Thus, using the conceptual support of restoration ecology and remote sensing, the work identified different vegetation performances in relation to the supporting ecological processes using the multispectral CO₂flux index, linked to the carbon flux to identify the photosynthetic effectiveness of the vegetation and the Topographic Wetness Index (TWI).

With a study in the Distrito Federal (DF), the results of the different performances of vegetation for ecological support, through electromagnetic signatures and associated vegetation formations, allowed for the identification of hotspots of greater integrity that indicate multifunctional areas to be preserved and critical areas that deserve planning actions using green infrastructure techniques for their restoration and integration into the landscape.

This approach could be the initial step towards establishing clear and assertive criteria for selecting areas with greater potential for the development of supporting ecological processes in the territorial mosaic.

This paper aims to give an oversight of what is being done by researchers in GIS and remote sensing (field) to explore minerals. The main objective of this review is to explore how GIS and remote sensing have been beneficial in identifying mineral deposits for easier and cost-effective mining.

The approach of this research used Web of Science to generate a database of published articles on the application of GIS and remote sensing techniques for mineral exploration. The literature was further digested, noting the main findings, adopted method, illustration and research scales.

When applied alone, each technique seems effective, but it is important to know that combining different methods is more effective in identifying ore deposits.

This paper also examined and provided possible solutions to both current and future perspective issues relating to the application of GIS and remote sensing to mineral exploration. The authors believe that the conclusions and recommendations drawn from case studies and literature review will be of great importance to geoscientists and policymakers.

The purpose of this paper is to evaluate the historical pollution of the Hostivar Reservoir (largest reservoir in Prague) sediment by metals, polyaromatic hydrocarbons (PAH) and polychlorinated biphenyls (PCB) and identify the trends in pollution of aquatic environment.

Core samples, 140 cm long, recording the 45-year history of the reservoir, were separated to 5 cm width subsamples (approximately 1.5 years of sedimentation) and analyzed for metals (Cd, Pb, Cu, Zn, Cr, Ni, Al), PAH and PCB. Following methods were used: US EPA 3051 for metals, US EPA 505 and US EPA 8082 A for PCB, and ISO 18287:2006 for PAH.

Most of the contaminants had the highest concentration at the beginning of the existence of the reservoir, suggesting that the contamination results from construction activities. Significant decrease of Pb occurred in the second half of the 1990s. It was caused by termination of the addition of lead as a detonation suppressant to the gasoline. Most concentrations of PAHs, PCBs and metals, except copper do not present eco-toxicological risk.

The results show the volume of priority pollutants removed from the reservoir by sediment extraction, and point risk to the terrestrial environment due to application of the sediment in the construction of a noise protecting wall.

The paper presents unique data about historical contamination of the largest reservoir in Prague, the capital of Czech Republic. It shows how the watershed and the construction phase of the dam cause a pollution of the reservoir sediment and possible environmental risk for aquatic biota.