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Abstract A 2007 earthquake in the western Solomon Islands resulted in a localised subsidence event in which sea level (relative to the previous coastal settings) rose approximately 30–70 cm, providing insight into impacts of future rapid changes to sea level on coastal ecosystems. Here, we show that increasing sea level by 30–70 cm can have contrasting impacts on mangrove, seagrass and coral reef ecosystems. Coral reef habitats were the clear winners with a steady lateral growth from 2006–2014, yielding a 157% increase in areal coverage over seven years. Mangrove ecosystems, on the other hand, suffered the largest impact through a rapid dieback of 35% (130 ha) of mangrove forest in the study area after subsidence. These forests, however, had partially recovered seven years after the earthquake albeit with a different community structure. The shallow seagrass ecosystems demonstrated the most dynamic response to relative shifts in sea level with both losses and gains in areal extent at small scales of 10–100 m. The results of this study emphasize the importance of considering the impacts of sea-level rise within a complex landscape in which winners and losers may vary over time and space.

Freshwater aquatic ecosystems are highly sensitive to flow regime alteration caused by anthropogenic activities, including river regulation and atmospheric warming-induced climate change. Either climate change or reservoir operations are among the main drivers of changes in the flow regime of rivers globally. Using modeled unregulated and simulated regulated streamflow under historical and future climate scenarios, this study evaluated potential changes to the flow regime due to climate change and reservoir operations for the major tributaries of the San Joaquin River Basin, California United States. We selected a set of Indicators of Hydrologic Alteration (IHA) to evaluate historical and projected future trends of streamflow dynamics: rise and fall rates, durations and counts of low and high pulses, and the magnitude of extremes. Results show that most indicators have pronounced departures from baseline conditions under anticipated future climate conditions given existing reservoir operations. For example, the high pulse count decreases during regulated flow conditions compared to increased frequency under unregulated flow conditions. Finally, we observed a higher degree of flow regime alteration due to reservoir operations than climate change. The degree of alteration ranges from 1.0 to 9.0% across the basin among all future climate scenarios, while reservoir operations alter the flow regime with a degree of alteration from 8.0 to 25%. This study extends multi-dimensional hydrologic alteration analysis to inform climate adaptation strategies in managed river systems.

[EN] In recent times, education for sustainability is gaining more and more relevance in the field of engineering. One of the recently established Sustainable Development Goals explicitly calls for the achievement of sustainable infrastructures by 2030. Infrastructures are recognised as a crucial element towards a sustainable future, as they are responsible for a vast amount of environmental damages and economic expenses, but also are considered to be essential to achieve social welfare and the economic development of regions. Sustainable design of infrastructures requires a paradigm shift in the way engineering students are taught how to face design problems. The complex relation that exists between the conflicting dimensions in which sustainability is founded, namely economy, environment and society, requires of future engineers to develop a series of transversal competencies during their postgraduate studies. However, there are no objective criteria on which to base the assessment of the degree of acquisition of these skills. This paper presents an objective methodology for the evaluation of one of the key competencies required for sustainability-oriented future engineers, namely critical thinking. The proposed methodology is based on the evaluation of the coherency expressed by the students when dealing with a sustainability-related design problem. Such consistency shall be mathematically quantified by means of the Analytic Hierarchy Process. Through the resolution of a particular case study, where students are required to complete a survey comparing different sustainability criteria pairwise, the professor is able to obtain a consistency index from the comparison matrices derived from the survey results of each student. Such indicator is a valuable tool to assess both the clarity with which students perceive sustainability as well as their ability to meet the new challenges that the society will face in the near future. The authors acknowledge the financial support of the Spanish Ministry of Economy and Competitiveness, along with FEDER funding (Project: BIA2017-85098-R).

The non-Antarctic Notothenioidei families, Bovichtidae, Pseudaphritidae and Eleginopsidae, diverged early from the main notothenioid lineage. They are important in clarifying the early evolutionary processes that triggered notothenioid evolution in the Antarctic. The early-diverged group represents 8% of all notothenioid species and never established themselves on the Antarctic shelf. Most attention has been paid to the Antarctic notothenioids and their limited physiological tolerance to climate change and increased temperatures. In this review, we discuss key life history traits that are characteristic of the non-Antarctic early-diverged notothenioid taxa as well as the genetic resources and population differentiation information available for this group. We emphasise the population fitness and dynamics of these species and indicate how resource management and conservation of the group can be strengthened through an integrative approach. Both Antarctic waters and the non-Antarctic regions face rapid temperature rises combined with strong anthropogenic exploitation. While it is expected that early-diverged notothenioid species may have physiological advantages over high Antarctic species, it is difficult to predict how climate changes might alter the geographic range, behaviour, phenology and ultimately genetic variability of these species. It is possible, however, that their high degree of endemism and dependence on local environmental specificities to complete their life cycles might enhance their vulnerability.

AbstractRecent research efforts have demonstrated increased bioerosion rates under experimentally elevated partial pressures of seawater carbon dioxide (pCO2) with or without increased temperatures, which may lead to net erosion on coral reefs in the future. However, this conclusion clearly depends on the ability of the investigated bioeroding organisms to survive and grow in the warmer and more acidic future environments, which remains unexplored. The excavating sponge Cliona orientalis Thiele, is a widely distributed bioeroding organism and symbiotic with dinoflagellates of the genus Symbiodinium. Using C. orientalis, an energy budget model was developed to calculate amounts of carbon directed into metabolic maintenance and growth. This model was tested under a range of CO2 emission scenarios (temperature + pCO2) appropriate to an Austral early summer. Under a pre‐industrial scenario, present day (control) scenario, or B1 future scenario (associated with reducing the rate of CO2 emissions over the next few decades), C. orientalis maintained a positive energy budget, where metabolic demand was likely satisfied by autotrophic carbon provided by Symbiodinium and heterotrophic carbon via filter‐feeding, suggesting sustainability. Under B1, C. orientalis likely benefited by a greater supply of photosynthetic products from its symbionts, which increased by up to 56% per unit area, and displayed an improved condition with up to 52% increased surplus carbon available for growth. Under an A1FI future scenario (associated with ‘business‐as‐usual’ CO2 emissions) bleached C. orientalis experienced the highest metabolic demand, but carbon acquired was insufficient to maintain the sponge, as indicated by a negative energy budget. These metabolic considerations suggest that previous observations of increased bioerosion under A1FI by C. orientalis may not last through the height of future A1FI summers, and survival of individual sponges may be dependent on the energy reserves (biomass) they have accumulated through the rest of the year.

Our long-term study gives a rare insight into meltwater hydrochemistry following the transition of Austre Brøggerbreen from polythermal to cold-based glaciation and its continued retreat. We find that the processes responsible for ion acquisition did not change throughout the period of records but became more productive. Two regimes before and after July/August 2000 were identified from changes in solute concentrations and pH. They resulted from increased chemical weathering occurring in ice-marginal and proglacial environments that have become progressively exposed by glacier retreat. Carbonate carbonation nearly doubled between 2000 and 2010, whilst increases in the weathering of silicate minerals were also marked. In addition, the end of ablation season chemistry was characterized by reactions in long residence time flow paths like those in subglacial environments, in spite of their absence in the watershed. Furthermore, the retreat of the glacier caused the sudden re-routing of meltwaters through its immediate forefield during 2009, which more than doubled crustal ion yields in this particular year and influenced chemical weathering in 2010 regardless of a low water flux. Such a “flush” of crustally derived ions can be meaningful for downstream terrestrial and marine ecosystems. We therefore find that, during glacier retreat, the recently exposed forefield is the most chemically active part of the watershed, making high rates of weathering possible, even when ice losses have caused a switch to cold-based conditions with no delayed subglacial drainage flowpaths. In addition, the drainage system reorganization events result in significant pCO2 depletion in an otherwise high pCO2 system.Keywords: High Arctic; Bayelva; meltwater geochemistry; chemical weathering in glacierized catchment; glacier retreat; climate change.(Published: 23 October 2014)Citation: Polar Research 2014, 33, 22779, http://dx.doi.org/10.3402/polar.v33.22779

Many studies illustrate variable patterns in individual species distribution shifts in response to changing temperature. However, an assemblage, a group of species that shares a common environmental niche, will likely exhibit similar responses to climate changes, and these community-level responses may have significant implications for ecosystem function. Therefore, we examine the relationship between observed shifts of species in assemblages and regional climate velocity (i.e., the rate and direction of change of temperature isotherms). The assemblages are defined in two sub-regions of the U.S. Northeast Shelf that have heterogeneous oceanography and bathymetry using four decades of bottom trawl survey data and we explore temporal changes in distribution, spatial range extent, thermal habitat area, and biomass, within assemblages. These sub-regional analyses allow the dissection of the relative roles of regional climate velocity and local physiography in shaping observed distribution shifts. We find that assemblages of species associated with shallower, warmer waters tend to shift west-southwest and to shallower waters over time, possibly towards cooler temperatures in the semi-enclosed Gulf of Maine, while species assemblages associated with relatively cooler and deeper waters shift deeper, but with little latitudinal change. Conversely, species assemblages associated with warmer and shallower water on the broad, shallow continental shelf from the Mid-Atlantic Bight to Georges Bank shift strongly northeast along latitudinal gradients with little change in depth. Shifts in depth among the southern species associated with deeper and cooler waters are more variable, although predominantly shifts are toward deeper waters. In addition, spatial expansion and contraction of species assemblages in each region corresponds to the area of suitable thermal habitat, but is inversely related to assemblage biomass. This suggests that assemblage distribution shifts in conjunction with expansion or contraction of thermal habitat acts to compress or stretch marine species assemblages, which may respectively amplify or dilute species interactions to an extent that is rarely considered. Overall, regional differences in climate change effects on the movement and extent of species assemblages hold important implications for management, mitigation, and adaptation on the U.S. Northeast Shelf.