Marine plastic pollution is currently a major scientific focus, with attention paid to its distribution and impacts within ecosystems. With recent estimates indicating that the mass of plastic released to the marine environment may reach 250 million metric tons by 2025, the effects of plastic on our oceans are set to increase. Distribution of microplastics, those plastics measuring less than 5 mm, are of increasing concern because they represent an increasing proportion of marine litter and are known to interact with species in a range of marine habitats. The local abundance of microplastic is dependent on a complex interaction between the scale of local plastic sources and prevailing environmental conditions; as a result, microplastic distribution is highly heterogeneous. Circulation models have been used to predict plastic distribution; however, current models do not consider future variation in circulation patterns and weather systems caused by a changing climate. In this study, we discuss the potential impacts of global climate change on the abundance and distribution of marine plastic pollution.
The 2015 Conservative Party Manifesto committed to “complete the network of [Marine Conservation Zones] MCZs”. Yet only 50 MCZs have been designated so far—well short of the 127 sites originally recommended by the regional projects in 2011. To fulfill this commitment, the third tranche of MCZs must be considerably larger and more ambitious than the previous two. The delay is unacceptable and we call on the Government to put in place this final piece of the MPA jigsaw as soon as possible.
Without effective management, surveillance and monitoring our MPAs are just lines on a map. Once a site is designated then its status as a MPA should be made the primary consideration for management and decision-making. The Government must act to protect MPAs properly by implementing a robust and well-coordinated management strategy. The Government should also consider investing in aerial and seaborne drones. We are shocked and disappointed by the Government’s decision to exclude reference areas from the third tranche of MCZs. Without reference areas the Government will be unable to properly assess how well the MPA network is performing.
The level of ambition shown by the FCO in designating MPAs in the UK Overseas Territories (UKOTs) has vastly exceeded ambitions in domestic waters - due in part to the very different circumstances. British seabirds off the Chagos Islands are better protected than they would be flying off Cornwall. However, many of the management problems experienced in domestic waters have been replicated in the UKOTs. The Government must now take action to ensure these sites are effectively resourced and managed.
The Government’s communications strategy in both the UK and the UKOTs is still ineffective and unsatisfactory, this is despite our predecessor Committee raising this as a concern in 2014. The lack of progress on this issue is self-defeating, as poor communication continues to make the process of designation and enforcement unnecessarily contentious.
The natural environment contributes to human wellbeing in a variety of ways, including providing outdoor recreation venues and underpinning cultural practices. Understanding whether the diversity of human-nature experiences significantly relate to overall subjective wellbeing, however, is rarely explored. Using results from 4418 respondents to an online survey conducted in Washington's Puget Sound region, we describe the relationship between overall life satisfaction and diverse metrics of how people engage with the natural environment. We found that eleven of the thirteen tested metrics had a small but positive correlation to overall life satisfaction and specific groupings of environment-specific social indicators were internally reliable constructs that predicted life satisfaction. These included: Sense of Place, Outdoor Activities, Good Governance, Social and Cultural Activities, Psychological Wellbeing, and Resource Access. This research empirically demonstrates that a variety of mechanisms for engaging the natural environment significantly contribute to overall subjective wellbeing.
Annual fast ice at Scott Base (Antarctica) in late summer contained a high biomass surface community of mixed phytoflagellates, dominated by the dinoflagellate, Polarella glacialis. At this time of the year, ice temperatures rise close to melting point and salinities drop to less than 20. At the same time, pH levels can rise above 9 and nutrients can become limiting. In January 2014, the sea ice microbial community from the top 30 cm of the ice was exposed to a gradient of pH and CO2 (5 treatments) that ranged from 8.87 to 7.12 and 5–215 µmol CO2 kg−1, respectively, and incubated in situ. While growth rates were reduced at the highest and lowest pH, the differences were not significant. Likewise, there were no significant differences in maximum quantum yield of PSII (Fv/Fm) or relative maximum electron transfer rates (rETRmax) among treatments. In a parallel experiment, a CO2 gradient of 26–230 µmol CO2kg−1 (5 treatments) was tested, keeping pH constant. In this experiment, growth rates increased by approximately 40% with increasing CO2, although differences among treatments were not significant.. As in the previous experiment, there was no significant response in Fv/Fm or rETRmax. A synchronous grazing dilution experiment found grazing rates to be inconclusive These results suggest that the summer sea ice brine communities were not limited by in situ CO2 concentrations and were not adversely affected by pH values down to 7.1.
The physical damages to benthic organisms caused by boat anchorages were assessed in the Arraial do Cabo Marine Extractive Reserve (ACMER), Brazil. It is one of the most visited scuba diving sites along the southwestern Atlantic. Through underwater visual observations, we analyzed if benthic organisms were damaged by anchors and/or anchor cabling at two dive sites. A total of 112 anchorages were sampled. Damages to benthic organisms were observed 139 times, mainly affecting epilithic algal matrix, the zoanthid Palythoa caribaeorum, and the fire coral Millepora alcicornis. Damages caused by anchor cables were significantly higher than those caused by anchors at one site. A significant difference between benthic organisms damaged was observed only for P. caribaeorum, caused by the anchor’s cable. We present evidence that, at current visitation levels, anchors are a relevant stressor to benthic organisms at dive sites in ACMER.
Ocean acidification poses an increasing threat to marine ecosystems and also interacts with other anthropogenic environmental drivers. A planned response strategy could minimize exposure of socioeconomic systems to potential hazards and may even offer wider advantages. Response strategies can be informed by understanding the hazards, assessing exposure and assessing risks and opportunities. This paper assesses exposure of key socioeconomic systems to the hazards of ocean acidification and analyzes the risks and opportunities of this exposure from Small Island Developing States (SIDS) perspectives. Key socioeconomic systems that are likely to be affected by ocean acidification are identified. A risk analysis matrix is developed to evaluate the risks or opportunities arising from ocean acidification. Analysis of the matrix reveals similarities and differences in potential adaptive responses at global and regional levels. For example, while ocean acidification poses significant threats to SIDS from more frequent toxic wild-caught seafood events and, potentially destruction of coral reef structure and habitat, SIDS may have a relative advantage in aquaculture and an important role to play in global marine ecosystem conservation.
Harvest strategies (HSs) have been applied to many data-rich fisheries, and are now increasingly being applied in data-limited situations. These have been evaluated using simulation frameworks, including management strategy evaluation (MSE), but few studies have considered the full spectrum from data-rich to data-limited strategies, in the context of the risk-cost-catch trade-off. This involves evaluating whether the cost of implementing a HS, the risk to the resource and catch taken from the resource have been appropriately balanced, given the value of the resource. HSs implemented for Australian Commonwealth fisheries were placed in eight tiers, ranging from data-rich to data-limited, and their performance evaluated using an MSE based on a full end-to-end ecosystem model. Generally, the risk to the resource increased as fewer data were available, due to biases in the assessments and slow response times to unexpected declines in resource status. The most data-rich tiers maximize discounted catches and profits over a 45-year projection period. However, the opportunity costs response is variable, and shows that the benefit of short-term high catches have to be compensated by resource recovery in the long term. On average, more data leads to improved management in terms of risk of being overfished and not reaching a target, but this requires lower initial catches to recover the resources and lower short-term discounted profits.
Seagrass global distribution has declined in the last decades due to many causes, and the implementation of recovery programmes as well as the development of new restoration techniques are needed. This work describes the development of an innovative restoration measure to enhance Zostera marina (eelgrass) seed germination and seedling survival in sediments inhabited by lugworms (Arenicola marina) and its validation in mesocosm experiments. The technique consists of placing 3 cm thick biodegradable coconut fibre mats (membrane) in the surface sediment to exclude the negative effects of sediment reworking (burial of seeds and destabilization/burial of seedlings). Two different flume mesocosm experiments were setup to test for: i) the effect of membranes on burial of Z. marina seeds; ii) the effect of membranes on survival and growth of Z. marina seedlings. The experiments were run for 8 and 10 weeks, respectively. Results show that the membrane was effectively preventing critical burial of Z. marina seeds as all seed mimics placed on the surface initially were recovered from 0 to 4 cm depth in the plots with membrane, while in the absence of the membrane, all seeds were buried to below the critical depth of 5–6 cm. The membrane also significantly enhanced the survival of Z. marina seedlings. The initial seedling density was in both cases 30/m2 and the final density was 26.0 ± 3.3/m2 with membrane versus 8.0 ± 1.6/m2without membrane. This new marine restoration measure showed to be effective on the reduction of the physical stress imposed by sediment reworking lugworms on Z. marina recovery, as a membrane keeps seeds at optimal depth for germination and protects seedlings from burial and erosion. In comparison to other measures, this new restoration technique is a low-tech nature-based solution. The results clearly show that this restoration technique can support Z. marina recovery through seeds and seedling protection. In this way, this technique contributes to decrease Z. marina vulnerability and increase its natural recovery potential and stability.
Aiming towards good practice in the planning and approval of offshore wind farms suggestions are provided for the amendment of environmental impact assessment (EIA), an effective marine spatial planning and the establishment of marine compensation measure. The investigation is focused on the situation in Germany as a frontrunner in ecological research on offshore wind energy. After 10 years of research in Germany, it is timely to offer a synopsis of the results especially regarding the successful investigations of mitigation measures. The results are based on published data collected in Germany over the last 10 years, as well as international research. The outcomes of the research were validated by interviewing experts using the Delphi method.
Key findings for good practice in impact assessment, mitigation and compensation:
1. EIAs should focus on decision-relevant subjects of protection (i.e. specific bird species and harbour porpoises).
2. There is a strong necessity for thresholds for the approval process.
3. Exclusion of OWFs in hotspots of sensitive species.
4. Application of state-of-the-art mitigation measures particularly against underwater noise to avoid damages of the hearing of porpoises.
5. The introduction of marine compensation measures is strongly suggested.
Capacity matrices are widely used for assessment of ecosystems services, especially when based on participatory approaches. A capacity matrix is basically a look-up table that links land cover types to ecosystem services potentially provided. The method introduced by Burkhard et al. in 2009 has since been developed and applied in an array of case studies. Here we adress some of the criticisms on the use of capacity matrices such as expert panel size, expert confidence, and scoring variability.
Based on three case-study capacity matrices derived from expert participatory scoring, we used three different approaches to estimate the score means and standard errors: usual statistics, bootstrapping, and Bayesian models. Based on a resampling of the three capacity matrices, we show that central score stabilizes very quickly but that intersample variability shrinks after 10–15 experts while standard error of the scores continues to decrease as sample size increases. Compared to usual statistics, bootstrapping methods only reduce the estimated standard errors for small samples. The use of confidence scores expressed by experts and associated with their scores on ecosystem services does not change the mean scores but slightly increases the standard errors associated with the scores on ecosystem services. Here, computations considering the confidence scores marginally changed the final scores. Nevertheless, many participants felt it important to have a confidence score in the capacity matrix to let them express uncertainties on their own knowledge. This means that confidence scores could be considered as supplementary materials in a participatory approach but should not necessarily be used to compute final scores.
We compared usual statistics, bootstrapping and Bayesian models to estimate central scores and standard errors for a capacity matrix based on a panel of 30 experts, and found that the three methods give very similar results. This was interpreted as a consequence of having a panel size that counted twice the minimal number of experts needed. Bayesian models provided the lowest standard errors, whereas bootrapping with confidence scores provided the largest standard errors.
These conclusions prompt us to advocate when the panel size is small (less than 10 experts), to use bootstrapping to estimate final scores and their variability. If more than 15 experts are involved, the usual statistics are appropriate. Bayesian models are more complex to implement but can also provide more informative outputs to help analyze results.