Abstract Bivalve shellfish aquaculture provides many benefits to society, beyond their traditional market value. This study collates the evidence available on the provisioning, regulating and cultural ecosystem services provided by the bivalve species commonly used in aquaculture. For the first time, it synthesises this evidence to provide a global assessment of the potential market and non‐market economic value of bivalve aquaculture. Bivalves are filter feeders, filtering water and particulates, creating substrates which provide habitat to act as nursery grounds for other species. Goods from provisioning services include meat, worth an estimated $23.9 billion as well as, pearls, shell and poultry grit, with oyster shell being the most important, with a global potential worth of $5.2 billion. The most important regulating services are nutrient remediation. Cultivated bivalves remove 49,000 tonnes of nitrogen and 6,000 tonnes of phosphorus, worth a potential $1.20 billion. Currently, there is little evidence on the cultural services per year of bivalve aquaculture, but we argue that these cultural values are broad ranging, although difficult to quantify. Our assessment indicates that the global, non‐food bivalve aquaculture services are worth $6.47 billion ($2.95 billion–9.99 billion) per annum. However, this is likely to be an underestimate of the true value of bivalve aquaculture as there are significant gaps in evidence of the value for a number of key services. The analysis presented here can be used to indicate the likely scale of payments for ecosystem services provided by bivalve aquaculture, prior to more detailed assessments.
Levels of reactive nitrogen (N) in the atmosphere have declined by around 25% in Europe since 1990. Ecosystem services provide a framework for valuing N impacts on the environment, and this study provides a synthesis of evidence for atmospheric N deposition effects on ecosystem services. We estimate the marginal economic value of the decline in N deposition on six ecosystem services in the UK. This decline resulted in a net benefit (Equivalent Annual Value) of £65 m (£5 m to £123 m, 95% CI). There was a cost (loss of value) for provisioning services: timber and livestock production of −£6.2 m (−£3.5 m to −£9.2 m, 95% CI). There was a cost for CO2 sequestration and a benefit for N2O emissions which combined amounted to a cost for greenhouse gas regulation of −£15.7 m (−£4.5 m to −£30.6 m). However, there were benefits for the cultural services of recreational fishing and appreciation of biodiversity, which amounted to £87.7 m (£13.1 m to £163.0 m), outweighing costs to provisioning and regulating services. Knowledge gaps in both the under-pinning science and in the value-transfer evidence prevent economic valuation of many services, particularly for cultural services, providing only a partial picture of N impacts which may underestimate the benefits of reducing N deposition.
People-environment interactions within nature-based solutions (NBS) are not always understood. This has implications for communicating the benefits of NBS and for how we plan cities. We present a framework that highlights a duality in NBS. The NBS as an asset includes both natural capital and human-centred capital, including organisational structures. NBS also exist as a system within which people are able to interact. Temporal and spatial scales moderate the benefits that NBS provide, which in turn are dependent on the scale at which social processes operate. Co-production and equity are central to the interactions among people and institutions in the design, use and management of NBS, and this requires clear communication. Drawing on ideas from culture-based development (CBD), we suggest an approach to communicate the benefits of NBS in a neutral but effective way. We propose guidelines for planning NBS that allow the optimisation of NBS locations and designs for particular outcomes.
Reliable quantification of ecosystem service (ES) provision in agricultural landscapes depends on accurate mapping of the spatial configuration of land-use and land cover (LULC). In this paper we explore the benefits of enhanced spatial and thematic resolution in LULC mapping in terms of predicting ecosystem services and associated natural capital-based land-use policies. Copernicus Sentinel-2 satellite images were processed using Google Earth Engine (GEE) to generate a LULC map at 10 m resolution, which was compared to existing datasets at 20 m, 25 m, and 100 m resolution in the River Welland catchment (Eastern England). Spatial resolution had a significant effect on the abundance and spatial configuration of land cover types. For example, detected woodland cover in the finest resolution dataset was 2x that in the coarsest data. Finer spatial resolution also allowed small, fragmented patches of woodland and grassland to be identified. ES provision (crop yield, carbon storage and pollinator abundance) was estimated from each map using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model. The finest resolution map resulted in 21% lower predicted wheat production (due to lower estimates of cultivated land cover), 7% higher predicted carbon stocks and 43% higher predicted wild bee abundance compared to the coarsest resolution map. The estimated monetary value of ES provision increased by 23.2% between the 10 and 100 m dataset. We recommend that a LULC resolution of at least 10 m should be employed in agricultural landscapes to accurately capture ES provision. This can be achieved using GEE and could be used as a basis for the development of future natural capital policy.
. 1. Saltmarsh conservation management often involves livestock grazing to maximise plant diversity and provide suitable breeding habitat for over‐wintering coastal birds. The effect of grazing on invertebrates is rarely quantified, but results from limited studies of terrestrial and coastal grasslands demonstrate greater abundance and species richness in un‐grazed grassland. 2. The impact of short sward (<8 cm) cattle grazing on the ground dwelling invertebrate community was assessed on an English inter‐tidal upper salt marsh using pitfall traps. Abundance, species richness, functional group structure, abundance of coastal specialists, environmental factors that influence invertebrate habitat choice and food web composition were compared for grazed and un‐grazed marsh. 3. In total, 90 000 invertebrates were sampled. Predatory, zoophagus and detritivorous Coleoptera were significantly more abundant on the un‐grazed marsh. In contrast, predatory Hemiptera and Araneae were significantly more abundant on the grazed marsh. Sheet weaver spiders were significantly more abundant on the grazed marsh, foliage running hunters and space web builders more abundant on the un‐grazed marsh. Most inter‐tidal coastal specialist species exhibited clear habitat preference for the grazed marsh. Total species richness was not significantly different between grazing treatments. 4. Linear direct gradient analysis showed that two environmental variables influenced by grazing intensity, soil temperature and vegetation height, significantly explained the composition of invertebrate functional groups. Larger bodied invertebrates dominated the un‐grazed food web. 5. We conclude that both short sward cattle grazed and un‐grazed saltmarsh habitat should be maintained to maximise invertebrate abundance and diversity and provide suitable habitat for coastal specialists.
