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Accurate counts of wild populations are essential to monitor change through time, but some techniques demand specialist surveyors and may result in unacceptable disturbance or inaccurate counts. Recent technological developments in unmanned aerial vehicles (UAVs) offer great potential for a range of survey and monitoring approaches. They literally offer a bird's‐eye view, but this increased power of observation presents the challenge of translating large amounts of imagery into accurate survey data. Seabirds, in particular, present the particular challenges of nesting in large, often inaccessible colonies that are difficult to view for ground observers, which are commonly susceptible to disturbance. We develop a protocol for carrying out UAV surveys of a breeding seabird colony (Lesser Black‐backed Gulls, Larus fuscus) and subsequent image processing to provide a semiautomated classification for counting the number of birds. Behavioral analysis of the gull colonies demonstrated that minimal disturbance occurred during UAV survey flights at an altitude of 15 m above ground level, which provided high‐resolution imagery for analysis. A protocol of best practice was developed using the expertise from both a UAV perspective and that of a dedicated observer. A GIS‐based semiautomated classification process successfully counted the gulls, with a mean agreement of 98% and a correlation of 99% with manual counts of imagery. We also propose a method to differentiate between the different gull species captured by our survey. Our UAV survey and analysis approach provide accurate counts (when comparing manual vs. semi‐automated counts taken from the UAV imagery) of a wild seabird population with minimal disturbance, with the potential to expand this to include species differentiation. The continued development of analytical and survey tools whilst minimizing the disturbance to wild populations is both key to unlocking the future of the rapid advances in UAV technology for ecological survey.

Alluvial and fluvial fans are the most widespread depositional landforms bordering the margins of long-lived highland regions and actively subsiding continental basins, across a broad spectrum of tectonic and climatic settings. Their significance is relevant not only to the local morphodynamics of mountain regions and proximal basinal sectors, but also to the long-term evolution of sediment-routing systems, affecting the propagation of stratigraphic signals of environmental change and the preservation potential of stratal successions over much larger spatial scales than those they occupy. Subaerial fan systems archive information on the palaeoclimate, local tectonic history and landscape response to various allogenic factors, although our ability to decipher such information is still limited. Early recognition of alluvial fans dates from the late nineteenth century, but a coordinated research community on these systems has been active only over the last few decades and the full relevance of fluvial fan systems to the geomorphology of present day continental basins and to the interpretation of ancient stratigraphic successions has been convincingly demonstrated only over the last decade. This introductory chapter summarizes advances in our knowledge of alluvial and fluvial fans, identifies potential new lines of future inquiry, and presents the contributions to this volume in the context of the current state of research.

No-till practices significantly reduce soil erosion rates. Cover crops are important in no-till systems to improve soil structural properties. Some beneficial effects of no-till in north-western Europe are less pronounced. The effect of no-till on the water related soil functions is still uncertain.

Following severe flooding in 2007, a decision was taken in 2012 to explore nature‐based solutions in 250‐km2 river catchment in the southern Cotswolds in the United Kingdom. The project involves working with landowners to create in channel, riparian, field, and woodland structures aimed at attenuating high flows or increasing infiltration rates to reduce flood risk. After 3 years, it is clear that the threshold for effectiveness requires the implementation of measures throughout large areas of the upstream catchment. Early results suggest that social, as well as natural, capital has been enhanced through the project. What is clear is the beneficial role of working with multiple stakeholders to implement natural flood management on a catchment wide scale. In this sense, the project has adopted a comanagement approach that brings together the knowledge of hydrologists, ecologists, farmers, woodland owners, and the local community to implement locally agreed solutions within a broader project framework. This paper will outline the initial findings and the governance structure within a theoretical framework of comanagement and suggest how this type of framework is suitable for a range of nature‐based solutions across Europe. However, the challenge remains in capturing the multiple benefits that such projects offer as these are often missed through conventional approaches such as cost–benefit analysis. The paper concludes by presented along with a potential way forward for a proof of concept for nature‐based solutions.

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Alluvial fans are dynamic landforms, the evolution of which is controlled by both external environmental forcing (climate, tectonics and base level change) and internal process‐form feedbacks. The latter include changes in flow configuration (between sheetflow and channelized flow states), driven by aggradation and degradation, which may in turn promote changes in sediment transport capacity. Recent numerical modelling indicates that such feedbacks may lead to dramatic and persistent fan entrenchment in the absence of external forcing. However, the parameterization of flow width within such models is untested to date and is subject to considerable uncertainty. This paper presents results from an experimental study of flow width dynamics on an aggrading fan in which spatial and temporal patterns of fan inundation are monitored continuously using analysis of digital vertical photography. Observed flow widths are compared with results from a simple theoretical model developed for non‐equilibrium (aggradational) conditions. Results demonstrate that the theoretical model is capable of capturing the first‐order characteristics of width adjustment over the course of the experiment, and indicate that flow width is a function of fan aggradation rate. This illustrates that models of alluvial flow width derived for equilibrium conditions may have limited utility in non‐equilibrium situations, despite their widespread use to date. Copyright © 2009 John Wiley & Sons, Ltd.

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