The Accuracy and Reliability of Traditional Surface Flow Type Mapping: Is It Time for A New Method of Characterising Physical River Habitat?

Surface flow types (SFT) are advocated as ecologically relevant hydraulic units, often mapped visually from the bankside to characterise rapidly the physical habitat of rivers. SFT mapping is simple, non-invasive and cost-efficient. However, it is also qualitative, subjective and plagued by difficulties in recording accurately the spatial extent of SFT units. Quantitative validation of the underlying physical habitat parameters is often lacking, and does not consistently differentiate between SFTs. Here, we investigate explicitly the accuracy, reliability and statistical separability of traditionally mapped SFTs as indicators of physical habitat, using independent, hydraulic and topographic data collected during three surveys of a c. 50m reach of the River Arrow, Warwickshire, England. We also explore the potential of a novel remote sensing approach, comprising a small unmanned aerial system (sUAS) and Structure-from-Motion photogrammetry (SfM), as an alternative method of physical habitat characterisation. Our key findings indicate that SFT mapping accuracy is highly variable, with overall mapping accuracy not exceeding 74%. Results from analysis of similarity (ANOSIM) tests found that strong differences did not exist between all SFT pairs. This leads us to question the suitability of SFTs for characterising physical habitat for river science and management applications. In contrast, the sUAS-SfM approach provided high resolution, spatially continuous, spatially explicit, quantitative measurements of water depth and point cloud roughness at the microscale (spatial scales ≤1m). Such data are acquired rapidly, inexpensively, and provide new opportunities for examining the heterogeneity of physical habitat over a range of spatial and temporal scales. Whilst continued refinement of the sUAS-SfM approach is required, we propose that this method offers an opportunity to move away from broad, mesoscale classifications of physical habitat (spatial scales 10-100m), and towards continuous, quantitative measurements of the continuum of hydraulic and geomorphic conditions which actually exists at the microscale.

Road Life Perspectives and Experiences Among Iranian Truck Drivers: a Qualitative Study

Truck drivers are one of the largest occupational groups in Iran. Evidence from previous studies suggests that working and living conditions on the road engender many concerns for truck drivers, and their families and communities. This research aimed to explore the experiences of Iranian truck drivers regarding life on the road. This qualitative study was conducted among Iranian truck drivers working in the inter-state transportation sector. A purposeful sample of 20 truck drivers took part in this research. Data were collected through semi-structured interviews and analyzed based on qualitative content analysis. After analysis of the data, three main themes emerged: "Individual impacts related to the hardships of life on the road life", "Family impacts related to the hardships of road life", and "Having positive attitude towards work and road". These findings represent the dimensions of perspectives in the road-life of truck drivers. Although truck drivers possess positive beliefs about their occupation and life on the road, they and their families face many hardships which should be well understood. They also need support to be better able to solve the road-life concerns they face. This study's findings are useful for occupational programming and in the promotion of health for truck drivers.