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A complex and sustainable watershed management strategy was implemented in Sri Lanka during the ancient Anuradhapura period, from the 5th century BC to the 11th century AD. Like modern watershed management strategies, it focused on flood prevention, soil erosion control, water quality control and water storage for irrigation. Tank cascade systems were the key element of these ancient watershed management installations. The wewas investigated were constructed in valleys characterised by fluvial accumulation. Sedimentological analyses of these tank cascade systems show that a precise age determination and the reconstruction of sediment and water f luxes as triggered by human-environment interactions are difficult. This is caused by the shallow character of the wewas leading to the steady redeposition of the tank sediments by wave motions during the wet season and agricultural use of the desiccated wewas during the dry season. Beyond, the sediments analysed allow to distinguish between the weathered parent bedrock and the overlying sediments. A differentiation between wewa deposits and the underlying fluvial deposits remains challenging.

In this study, we investigated the stability and reactivation of preexisting Tonghua landslide deposits in China, including the adjacent stable slope. We used an integrated approach, combining a multichannel analysis of surface waves (MASW) and electrical resistivity tomography (ERT). We used ERT to determine groundwater seepage paths, weathering conditions, water content, and the depth to bedrock. High-resolution two-dimensional (2D) shear-wave velocity MASW images, on the other hand, played an essential role in detecting both horizontal and vertical compositions, disjointedness, and sliding surfaces related to lithological borders. Based on seismic models, we considered four geological layers encountered in the stable slope, including fractured (gravel) and weathered (phyllite) materials, as a sliding mass. We combined the 2D resistivity profiles obtained to create pseudo-three-dimensional ERT images to estimate water-saturated and unsaturated masses. From the tomography results, we identified different preexisting deposits, including buried arable clay deposits, old accumulated earthflow deposits, a water accumulation zone, and a fissure runoff. Based on the resistivity results, the bottom of the earthflow deposits is susceptible to water, and oversaturation can reactivate the earthflow.

This integrated pedo-geoarchaeological study focuses on three abandoned prehispanic terrace agricultural systems near Laramate in the southern Andes of Peru, aiming to unravel the pedological and land-use history of the region. The investigation involved contextualizing the former agricultural management system within its paleoecological framework and assessing the impact of agricultural practices on soil development and quality. The Laramate terrace complex, with its diverse terrace systems and varied geomorphological settings, provided an ideal setting for the investigation. Comparative analyses between non-irrigated agricultural terrace soils and undisturbed reference sequences were conducted, employing a range of methodologies, including surveys, soil analysis, GIS and remote sensing, palaeobotany, and radiocarbon dating. The study identifies three WRB Reference Soil Groups in the Laramate region: Phaeozems , Andosols , and Anthrosols. Unique characteristics of Phaeozems challenge typical descriptions, influenced by factors such as climatic seasonality, vegetation, fauna, lithology, and aeolian inputs. Despite long-term use, terrace soils (Anthrosols) show no severe degradation, maintaining balanced acidity and nutrient availability for successful crop cultivation. Tillage horizons of all terrace soils exhibit elevated organic matter content, highlighting the sustainability of prehispanic agricultural practices through a consistent application of organic manure. Phytolith concentrations indicate extensive agricultural activities, particularly maize cultivation, with varying patterns suggesting changes in cultivation or fertilization practices over time. Starch grain identification aligns with phytolith analyses, reinforcing maize's significance in the region. Notably, the abandonment of the prehispanic cultivation system was not linked to soil exhaustion or terrace instability. The prehispanic history of terraced agriculture in the Laramate region extends over four development phases, reflecting dynamic interactions between environmental, cultural, and agricultural factors. The initial phase, from the Formative Paracas period to the Early Nasca period (800 BCE–200 CE), witnessed the establishment of agricultural terraces with simple terrace architecture, while the Middle Horizon (600–1000 CE) saw systematic areal expansion influenced by the Wari culture. Adaptations to drier conditions included terraced agriculture on volcanic soils. The Late Intermediate Period (1000–1450 CE) witnessed hydrological variability and further terrace expansion to lower altitudes and less agriculturally suitable locations. The final phase, marked by the onset of the Hispanic colonial period in 1532 CE, saw the gradual abandonment of terraced agricultural systems due to demographic shifts and reorganization of production systems. Despite this, the historical trajectory underscores the adaptability and resilience of prehispanic communities in the Laramate region, showcasing innovative terrace agriculture as a means of coping with changing environmental conditions across diverse landscape units. [ABSTRACT FROM AUTHOR]

In ancient Egypt, lakes, canals, and other water bodies were an essential part of the sacred landscape in which temples were embedded. In recent years, geoarchaeological research at the site of the Temple of Bastet at Bubastis in the southeastern Nile Delta has proven the existence of two water canals surrounding the temple. It has now been investigated whether these canals were connected to the Temple of Pepi I (2300–2250 B.C.E.), located approximately 100 m to the west of the Temple of Bastet. To explore the Holocene landscape genesis of the Temple of Pepi I, 15 drillings and six geoelectrical profile lines were performed in the surroundings of the temple in spring 2022. The results show loamy to clayey sediments in deeper sections of all drillings with a maximum thickness of 1.70 m, indicating a marshy or swampy depositional environment. Based on the recovered sediment sequences and archaeological remains in the vicinity of the Temple of Pepi I, the marshy or swampy area existed before the Fourth Dynasty. During the Old Kingdom (ca. 2850–2180 B.C.E.), the former marshland either dried up through natural processes or was intentionally drained and filled with sediments for subsequent use for occupation. Regarding the original research question, there is as yet no evidence for a direct connection to the canals of the Temple of Bastet. [ABSTRACT FROM AUTHOR]

The unsustainable take-make-dispose linear economy prevalent in healthcare contributes 4.4% to global Greenhouse Gas emissions. A popular but not yet widely-embraced solution is to remanufacture common single-use medical devices like electrophysiology catheters, significantly extending their lifetimes by enabling a circular life cycle. To support the adoption of catheter remanufacturing, we propose a comprehensive emission framework and carry out a holistic evaluation of virgin manufactured and remanufactured carbon emissions with Life Cycle Analysis (LCA). We followed ISO modelling standards and NHS reporting guidelines to ensure industry relevance. We conclude that remanufacturing may lead to a reduction of up to 60% per turn (−1.92 kg CO 2 eq, burden-free) and 57% per life (−1.87 kg CO 2 eq, burdened). Our extensive sensitivity analysis and industry-informed buy-back scheme simulation revealed long-term emission reductions of up to 48% per remanufactured catheter life (−1.73 kg CO 2 eq). Our comprehensive results encourage the adoption of electrophysiology catheter remanufacturing, and highlight the importance of estimating long-term emissions in addition to traditional emission metrics. [ABSTRACT FROM AUTHOR]