No abstract

W e are currently witnessing the fourth industrial revolution 1 . Technological innovations have altered the way in which economies operate and how people interact with built, social and natural environments. One area of transformation is the emergence of robotics and autonomous systems (RAS), defined as technologies that can sense, analyse, interact with and manipulate their physical environment 2 . RAS include unmanned aerial vehicles (drones), self-driving cars, robots able to repair infrastructure, and wireless sensor networks used for monitoring. RAS therefore have a large range of potential applications, such as autonomous transport, waste collection, infrastructure maintenance and repair, policing 2,3 and precision agriculture 4 (Fig. 1). RAS have already revolutionized how environmental data are collected 5 and how species populations are monitored for conservation 6 and/or control 7 . Globally, the RAS market is projected to grow from $6.2 billion in 2018 to $17.7 billion in 2026 8 .Concurrent with this technological revolution, urbanization continues at an unprecedented rate. By 2030, an additional 1.2 million km 2 of the planet's surface will be covered by towns and cities, with ~90% of this development happening in Africa and

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Kelps (Laminariales, Ochrophyta) are ecologically and commercially important habitatforming brown macroalgae, found in coastal ecosystems worldwide. Their presence in the sublittoral fringe makes monitoring kelp forests problematic and consequently they remain relatively understudied. Remote sensing offers new avenues to monitor difficult-to-access biomes, particularly kelp habitats, but previous monitoring efforts have only been tested on an ad hoc basis and a standardised protocol for monitoring kelp requires development. In view of ongoing and emerging threats to kelp, there is a need for monitoring to establish detailed baseline information. Wild harvesting of kelp is increasing, illustrated by growing numbers of seaweed and seaweed-containing products. Simultaneously, climate change is causing sea-surface temperatures to rise and influencing kelp distribution and abundance globally. This study reviews the potential for remote sensing in macroalgal studies, with an emphasis on kelp and provides a conceptual framework to support the development of standardised monitoring protocols. Satellite-born sensors and aerial photography have been effective, but these distant sensors cannot operate effectively in turbid temperate waters, and many image surveys do not account for changing tides. Advances are being made in acoustic monitoring, particularly multibeam sonar. With some development, there is great potential for a standardised monitoring protocol for kelp, aiding management and conservation efforts.

Benthic habitats are important elements of polar marine environments, but can be vulnerable to anthropogenic influences such as trawling. Bottom trawling can reduce diversity and alter communities, although some habitats show resilience. The shrimp trawl fishery of West Greenland is a significant part of Greenland's economy. It operates along the west coast from the narrow rockier shelf of the south, up to deeper, muddy areas around Disko Bay. Here we use a benthic drop camera to sample 201 sites between latitudes 60–72°N and depths of 61–725m. Linear models examined relationships of taxon abundance and diversity with bottom trawling intensity and environment (depth, temperature, current, iceberg concentration). Trawling intensity is the most important factor determining the overall abundance of benthic organisms, accounting for 12–16% of variance, although environmental conditions also show significant associations. Sessile erect organisms such as corals show a significant negative response to trawling. Soft sediment communities show a higher resilience than rocky areas. On soft sediments significantly lower abundance characterises sites trawled under five years ago. On hard/mixed ground reduced abundance remains characteristic of sites trawled a decade ago. Continued monitoring of benthic habitats is an essential part of evaluating the ongoing impacts of trawl fisheries.