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Gully erosion is a formidable land degradation process globally. It is omnipresent across India, wherein two of the largest badlands regions in the world also exist. However, despite being affected by widespread gullying, gully erosion research in India has been rather limited, with key aspects of gully formation, morphologies and dynamics remaining unknown. Through this comprehensive systematic review, we synthesise previous studies on gully erosion in India and in turn highlight pivotal knowledge gaps. The review starts with a discussion of the causal factors of gullying in India, which underlines how gully initiation in several regions was an aftermath of deforestation and overgrazing. Contrastingly, the badlands of Central and Western India have mainly developed in response to natural triggers like neotectonics and Holocene climate change. The section on mapping highlights how mapping methodologies have not only been dictated by the availability of imagery and/or means of data processing, but also the mapping purpose—that is, individual gully channels or entire badlands. Although a few studies applying concepts of fractal geometry to characterise badlands’ geomorphology are innovative and unique, the most striking research gaps we have identified also pertain to understanding and quantification of gully geomorphology and erosion dynamics in different regions of India. Our review reveals that gullies of peninsular India have been the least studied, followed by those of the Himalayan and Sub-Himalayan region. Although the literature provides interesting examples of linkages between badlands development and the wider geomorphic evolution of the landscape, better chronological understanding is required to disentangle the relative importance of natural and anthropogenic drivers of landscape change in India’s badlands. Large-scale mapping of gully characteristics, quantification of gully morphologies, gully erosion rates and its share in catchment sediment budget across various physiographic regions or river basins of the country also constitute important areas for future research.

Upland blanket peat is widespread in the headwaters of UK catchments, but much of it has been degraded through atmospheric pollution, vegetation change and erosion. Runoff generation in these headwaters is an important element of downstream flood risk and these areas are increasingly the focus of interventions to restore the peat ecosystem and to potentially mitigate downstream flooding. Here we use a series of multivariate analysis techniques to examine controls on storm runoff behavior within and between ten blanket peat catchments all within 5 km of one another and ranging in size from 0.2-3.9 hectares. We find that: 1) for all 10 catchments, rainfall intensity is the dominant driver for both magnitude and timing of peak discharge, and that total and antecedent rainfall is important for peak discharge only in small storms; 2) there is considerable inter-catchment variability in: runoff coefficient, lag time, peak runoff, and their predictability from rainfall; however, 3) a significant fraction of the inter-catchment variability can be explained by catchment characteristics, particularly catchment area; and 4) catchment controls on peak discharge and runoff coefficient for small storms highlight the importance of storage and connectivity while those for large events suggest that surface flow attenuation dominates. Together these results suggest a switching rainfall-runoff behavior where catchment storage, connectivity and antecedent conditions control small discharge peaks but become increasingly irrelevant for larger storms. Our results suggest that, in the context of Natural Flood Management potential, expanding depression storage (e.g. distributed shallow water pools) in addition to existing restoration methods could increase the range of storms within which connectivity and storage remain important and that for larger storms measures which target surface runoff velocities are likely to be important.

Over the last century, under the modern hydraulic model, waterways across the world have been heavily canalized and culverted, driven into underground pipes, drains and sewers. This hydraulic approach has hardwired an isolated water network into the urban fabric, fragmenting erstwhile patterns and dynamics of life, both human and nonhuman. Ecologically, it has been hugely damaging, reducing water quality and biotic diversity, but also socially, disconnecting citizens from the waterways that service and characterize the city. Consequently, since the 1990s, waterway restoration has become widespread as a design solution to degraded rivers and streams, reinstating compromised hydrological, geomorphological and ecological processes. Deculverting or ‘daylighting’, the focus of this paper, is a radical form of restoration, opening up subterranean, culverted waterways often forgotten by communities above ground. Yet, as this paper emphasizes, waterway restoration has tended to privilege ecological over social objectives, while public engagement in project conceptualization has been limited, conducted ‘downstream’ subsequent to planning and design stages. Restoration schemes have therefore tended to reflect the concerns of professionals rather than communities, overlooking their potential for social renewal and change. Drawing on workshop data collected through participatory mapping exercises, this paper explores the case for daylighting a culverted brook in Urmston, Greater Manchester, focusing in particular on the preferences, concerns and knowledge of local residents. The paper compares professional and community perspectives on the preferred scheme design and potential benefits of daylighting, drawing out differences and tensions between them, temporarily ‘unblackboxing’ the brook. It is ventured that daylighting can unleash the social ‘stickiness’ of water, its proclivity to draw and bind together, to revitalize the park, enhancing connection to wildness, attachment to place and sense of community. This is particularly crucial in the face of decreased local authority funding and related crises in park management.

Restoration of eroded blanket peatlands through revegetation and gully blocking is observed to also deliver significant natural flood management (NFM) benefits (reduce and delay floodpeaks). But there is a lack of clear understanding regarding how different catchment processes interact/counteract under each intervention scenario. We seek to provide more insight by rigorously calibrating TOPMODEL rainfall-runoff model to different experimental catchments each representing an intervention scenario. Through numerical experimentation with the calibrated parameters, we estimate the impact-magnitude of different processes. Our findings confirm the NFM benefits of these restoration-focused interventions. In both interventions and in our largest storms, both the delay and reduced floodpeaks are primarily due to surface roughness reducing the floodwave speed thus thickening the overland flow; we conceptualize this as an increase in a “kinematic storage.” Impact of gully blocking in increasing kinematic storage is very significant and comparable to that of revegetation alone. Interventions' impact on “static storage” (interception + ponding + evapotranspiration) becomes important for smaller storms. Although interventions always increase lag times, they can be less effective in reducing peak magnitude when maximum rainfall intensity is sustained for durations longer than mean catchment delay. We propose two approaches to further increase catchment's static and kinematic storage. Finally, while our field-scale numerical study contributes to the evidence-base for NFM's effectiveness, it also provides a basis for modeling these interventions in the future. Such catchment-scale numerical studies are necessary to extend our findings to spatial scales where flooding can cause socioeconomic damage, and to provide a tool for optimizing the distributed configuration of these interventions.

Peatlands are wetland ecosystems with great significance as natural habitats and as major global carbon stores. They have been subject to widespread exploitation and degradation with resulting losses in characteristic biota and ecosystem functions such as climate regulation. More recently, large-scale programmes have been established to restore peatland ecosystems and the various services they provide to society. Despite significant progress in peatland science and restoration practice, we lack a process-based understanding of how soil microbiota influence peatland functioning and mediate the resilience and recovery of ecosystem services, to perturbations associated with land use and climate change.\ud \ud We argue that there is a need to: in the short-term, characterise peatland microbial communities across a range of spatial and temporal scales and develop an improved understanding of the links between peatland habitat, ecological functions and microbial processes; in the medium term, define what a successfully restored ’target’ peatland microbiome looks like for key carbon cycle related ecosystem services and develop microbial-based monitoring tools for assessing restoration needs; and in the longer term, to use this knowledge to influence restoration practices and assess progress on the trajectory towards ‘intact’ peatland status.\ud \ud Rapid advances in genetic characterisation of the structure and functions of microbial communities offer the potential for transformative progress in these areas, but the scale and speed of methodological and conceptual advances in studying ecosystem functions is a challenge for peatland scientists. Advances in this area require multidisciplinary collaborations between peatland scientists, data scientists and microbiologists and ultimately, collaboration with the modelling community.\ud \ud Developing a process-based understanding of the resilience and recovery of peatlands to perturbations, such as climate extremes, fires, and drainage, will be key to meeting climate targets and delivering ecosystem services cost effectively.

Understanding the spatial variability of gaseous carbon flux at a landscape scale requires intensive monitoring campaigns necessitating significant and perhaps prohibitive financial investment. Commercially available CO2 sensors may only partially fulfil the requirements of the researcher, thereby generating inadequate data. In this context we present the fully replicable designs for a low-cost, microcontroller-based gaseous CO2 concentration data logger suitable for field deployment at scale. It demonstrates a post-calibration accuracy of 96-99% and large onboard data storage for data collected at user-defined intervals. The sensor can be powered via USB or batteries, assembled by novice users, and produced for approximately £155. Post-calibration it was used to measure CO2 evasion from a peatland stream, environments known to be spatially and temporally variable CO2 sources, although potential applications are much wider in scope. The proliferation of low-cost, open-source, and user-made sensors in physical sciences could allow researchers to answer questions previously unanswerable due to the limitations of existing proprietary equipment. We encourage other research teams to use and adapt this design for a range of purposes and research questions beyond carbon processing in peatlands.