Coastal tourism developed along the Valparaíso region of Chile is being threatened by a very particular issue: scenery degradation related to extreme urbanization and collateral effects. This paper presents the results of scenic evaluation of 96 sites along this region. The scenic evaluation assesses values from a checklist of 18 physical and 8 human parameters, and permits calculation of a scenic evaluation index (D Value), which classifies coastal sites into five classes: Class I, usually natural areas of top scenic characteristics, to Class V, poor scenic natural areas with a higher impact of human interventions. In summary, 14 sites (15%) appeared in Class I; 7 (7%) in Class II; 9 (9%) in Class III; 17 (18%) in Class IV and 49 sites (51%) in Class V. This evaluation provides a complete scenic assessment overview of the Valparaiso Region, allowing implementation of an adequate management strategy based on knowledge of coastal scenery for the maintenance and preservation of scenic quality.
Human Impacts on the Environment
As human activities increasingly threaten biodiversity [1, 2], areas devoid of intense human impacts are vital refugia . These wilderness areas contain high genetic diversity, unique functional traits, and endemic species [4, 5, 6, 7]; maintain high levels of ecological and evolutionary connectivity [8, 9, 10]; and may be well placed to resist and recover from the impacts of climate change [11, 12, 13]. On land, rapid declines in wilderness  have led to urgent calls for its protection [3, 14]. In contrast, little is known about the extent and protection of marine wilderness [4, 5]. Here we systematically map marine wilderness globally by identifying areas that have both very little impact (lowest 10%) from 15 anthropogenic stressors and also a very low combined cumulative impact from these stressors. We discover that ∼13% of the ocean meets this definition of global wilderness, with most being located in the high seas. Recognizing that human influence differs across ocean regions, we repeat the analysis within each of the 16 ocean realms . Realm-specific wilderness extent varies considerably, with >16 million km2 (8.6%) in the Warm Indo-Pacific, down to <2,000 km2 (0.5%) in Temperate Southern Africa. We also show that the marine protected area estate holds only 4.9% of global wilderness and 4.1% of realm-specific wilderness, very little of which is in biodiverse ecosystems such as coral reefs. Proactive retention of marine wilderness should now be incorporated into global strategies aimed at conserving biodiversity and ensuring that large-scale ecological and evolutionary processes continue.
Coastal ecosystems are ecologically, culturally, and economically important, and hence are under pressure from diverse human activities. We reviewed the literature for existing evidence of effects of human-induced habitat changes on exploited fish utilizing coastal habitats. We focused on fish species of the Northeast Atlantic for which fisheries advice is provided by International Council for the Exploration of the Sea (ICES) and which utilize coastal habitats for at least one life-history stage (LHS). We found that 92% of these species are impacted by human activity in at least one LHS while utilizing coastal habitat and 38% in multiple stages. Anthropogenic pressures most commonly shown to impact these fish species were toxicants and pollutants (75% of species). Eutrophication and anoxia, invasive species, and physical coastal development affected about half of the species (58, 54, and 42% of species, respectively), while indirect fishing impacts affected a minority (17% of species). Moreover, 71% of the ICES advice species that utilize coastal habitats face impacts from more than one pressure, implying cumulative effects. Given that three-fourths of the commercial landings come from fish species utilizing coastal habitats, there is an obvious need for a better understanding of the impacts that human activities cause in these habitats for the development of ecosystem-based fisheries management.
The persistence of populations of marine organisms depends on the success of the dual processes of reproduction and recruitment. The production of offspring alone is inconsequential unless larvae and propagules can recruit, which often entails a period of development and distribution in the water column and subsequent selection of appropriate habitats. For fish, this may mean drifting in currents before responding to particular habitat cues. For corals and other benthic invertebrates, larvae must undergo site selection, settlement and metamorphosis into the juvenile form, and survivorship is directly linked to site choice and environmental conditions. Both biotic and abiotic factors affect population replenishment success, and hence, anthropogenic influences such as pollution, sedimentation and climate change can negatively affect critical processes such as reproductive synchronization in spawning species, successful embryological development, appropriate site selection, settlement, metamorphosis and in the case of reef building corals, acquisition of the required zooxanthellae partner. Effective management practices are essential for ensuring the persistence of populations of coral reef organisms of economic, cultural and ecological value.
Cold-water corals form high biodiversity habitats in the deep sea. They are generally long-lived, slow-growing, and thus particularly vulnerable to anthropogenic impact. We used high-definition imagery to quantify the impact and assess the recovery of deep-sea corals that were affected by the 2010 Deepwater Horizon oil spill in the Gulf of Mexico. Over three hundred Paramuricea spp. colonies were imaged yearly between 2011 and 2017 at five sites, and the images were digitized to quantify health, hydroid overgrowth, identify branch loss, and track recovery patterns. Although the median level of impact decreased after 2011 at all impacted sites, it has been stable since then and remained higher than at the reference sites. Recovery depended on the initial level of impact to the colonies, which negatively affected the ability of individual branches to recover or remain healthy. The effect of initial impact on recovery between consecutive years was still visible seven years after the spill, indicating a long-term, non-acute, impact on the colonies. Injured corals were also more likely to lose branches, and branch loss was still significantly higher at some of the impacted sites between 2016 and 2017, indicating an ongoing effect of the spill, which may eventually lead to delayed mortality. The methodology we employed allows us to successfully detect small changes in the health of corals. We suggest the establishment of image-based coral-monitoring sites to collect baseline data on coral biology, assess the efficacy of Marine Protected Areas, and detect future anthropogenic impact to these vulnerable deep-sea ecosystems.
Marine litter (ML) contaminates essentially all global coastal and marine environments and drives multiple ecosystem-level effects. Although deleterious effects of ML on several organisms have been investigated in the last years, this information tends to be dispersed or underreported, even in marine biodiversity hotspots such as reef ecosystems. Two are the main goals of this paper: (i) to integrate and synthesize current knowledge on the interactions of ML and reef organisms, and (ii) to evaluate the multiple disruptions on the ecological processes in reef systems. We report here ML-driven ecological disruptions on 418 species across eight reef taxa, including interactions that were previously not addressed in detail, and evaluate their major conservation implications. These results can help raise awareness of global impacts on the world's reefs by highlighting ML associations in different reef systems around the world, and can aid in ML input reduction and marine management.
In November and December 2016, local residents around St. Mary’s Bay, Nova Scotia, Canada, noticed something alarming: thousands of dead fish were washing up along the coast. Scientists from the Canadian government’s Department of Fisheries and Oceans investigated, but the cause remains a mystery. This research note excogitates a potential cause: dumped chemical and conventional munitions. Between 1918 and 1972, most industrialized countries disposed of surplus munitions at sea. As a result, hundreds of millions of tons of corroded ordnance now pollute marine environments around the world. The article then discusses various research obstacles impeding further scholarly investigations and the possible connections between underwater munitions and the mass death of aquatic life.
As human activities continue to expand globally, there will be increased need to incorporate the impacts of these activities into ecological studies for a holistic understanding of ecosystems. Within the Southern California Bight, as in other highly productive marine ecosystems, fishing has long contributed to the ecology and evolution of marine fish and invertebrate communities. As fishing varies across space and over time, there is a need for a reliable metric that quantifies the spatiotemporal variation in the impact of fishing. Here, we quantify an index of harvest intensity on the highly productive and heavily fished, shallow rocky reefs of Southern California. To this end, we take advantage of two long‐term, spatially explicit, multi‐species datasets collected by the California Department of Fish and Wildlife on commercial and recreational marine harvest, combined with reef‐species survey data and a geospatial reef data layer. Using this approach, we recover predictable patterns for harvest intensity across the Southern California Bight, with harvest intensity decreasing in fishing blocks located at greater distances from the nearest port. Further, our results indicate an important interaction effect between distance to nearest port and year on harvest intensity, suggesting there are important shifts in spatiotemporal patterns over the 30‐year time period. As fishing can have numerous impacts on ecological and evolutionary processes, the observed spatiotemporal variation in harvest intensity illustrates the need for incorporating the contribution of human impacts into marine ecosystem studies.
This study examines the use of water-use fees in California’s bidding-based power markets to balance freshwater conservation and reduction of the marine ecosystem impact of coastal once-through-cooled power plants. An hourly power dispatch is simulated using the state’s 2014 demand and generation capacity data. Fees on ocean water withdrawals of $5–120/acre-ft are simulated in three scenarios that test the grid’s ability to simultaneously mitigate its impact on marine ecosystems, conserve freshwater, and incentivize recycled water use. Although fees modeled represent a small share of generator fuel costs, results show that they trigger declines in ocean water withdrawals of up to 11% that are almost always cost-effective if accounting for effects on system-wide fuel costs and CO2 emissions. An appropriately designed fee-structure reduces ocean water withdrawals by 9% without increasing freshwater consumption elsewhere. Wholesale electricity price increases of 5–10% are concentrated in Northern California, and marine ecosystem benefits are partly offset by increases in NOx and SO2 emissions inland. Overall, this study finds that water-use fees could be an effective strategy for reducing the marine ecosystem impacts of California’s power sector, particularly because they can also address short term fluctuations in freshwater scarcity. Keywords: Energy-water nexus, once-through cooling, scarce water, environmental pricing, energy policy, electricity dispatch, power systems.
Accelerating coastal development and shipping activities dictate that dredging operations will intensify, increasing potential impacts to fishes. Coastal fishes have high economic, ecological, and conservation significance and there is a need for evidence‐based, quantitative guidelines on how to mitigate the impacts of dredging activities. We assess the potential risk from dredging to coastal fish and fisheries on a global scale. We then develop quantitative guidelines for two management strategies: threshold reference values and seasonal restrictions. Globally, threatened species and nearshore fisheries occur within close proximity to ports. We find that maintaining suspended sediment concentrations below 44 mg/L (15–121 bootstrapped CI) and for less than 24 hours would protect 95% of fishes from dredging‐induced mortality. Implementation of seasonal restrictions during peak periods of reproduction and recruitment could further protect species from dredging impacts. This study details the first evidence‐based defensible approach to minimize impacts to coastal fishes from dredging activities.