Fast Climate Change Research Articles

Coal fly ash and nitrogen application as eco-friendly approaches for modulating the growth, yield, and biochemical constituents of radish plants

Plants are confronting a variety of environmental hazards as a result of fast climate change, which has a detrimental influence on soil, plant growth, and nutrient status. As a result, the present study aims to evaluate the influence of various fly ash concentrations (5, 10, 15, 20, 25, 30, and 35% FA) mixed with the optimum concentrations of nitrogen in the form of urea (0.5 g pot−1) on the growth, productivity and biochemical constituents of radish plants. Energy-dispersive X-ray spectroscopy (EDX) and scanning electron microscopy (SEM) were used to assess soil physical–chemical properties and FA nutrient status. Results suggested that FA added many essential plant nutrients to the growth substrate and improved some important soil characteristics such as pH, electric conductivity, porosity, and water holding capacity. Also, the results revealed that the low concentrations of FA up to 20% were found to boost radish growth, yield, chlorophyll, carotenoids, and mineral content. While the highest concentrations of FA (25–35%) decreased radish growth and yield, increased oxidative stress through increased lipid peroxidation (MDA) and caused a significant boost in ascorbic acid, proline, protein, and antioxidant enzyme activities. Furthermore, SEM of radish leaf revealed an enhancement in the stomatal pore of radish leaf under different levels of FA. In conclusion, combining 15% fly ash with 0.5 g nitrogen in the form of urea significantly enhanced radish yield by enhancing antioxidant activity such as catalase, peroxidase, ascorbate peroxidase, Guaiacol peroxidase, superoxide dismutase, nitrate reductase and reducing oxidative stress, potentially reducing fly ash accumulation and environmental pollution.

Components of 21 years (1995–2015) of absolute sea level trends in the Arctic

Abstract. The Arctic Ocean is at the frontier of the fast-changing climate in the northern latitudes, and sea level trends are a bulk measure of ongoing processes related to climate change. Observations of sea level in the Arctic Ocean are nonetheless difficult to validate with independent measurements, and this is globally the region where the sea level trend (SLT) is most uncertain. The aim of this study is to create a satellite-independent reconstruction of Arctic SLT, as it is observed by altimetry and tide gauges (TGs). Previous studies use Gravity Recovery and Climate Experiment (GRACE) observations to estimate the manometric (mass component of) SLT. GRACE estimates, however, are challenged by large mass changes on land, which are difficult to separate from much smaller ocean mass changes. Furthermore, GRACE is not available before 2003, which significantly limits the period and makes the trend more vulnerable to short-term changes. As an alternative approach, this study estimates the climate-change-driven Arctic manometric SLT from the Arctic sea level fingerprints of glaciers, Greenland, Antarctica and glacial isostatic adjustment (GIA) with the addition of the long-term inverse barometer (IB) effect. The halosteric and thermosteric components complete the reconstructed Arctic SLT and are estimated by interpolating 300 000 temperature (T) and salinity (S) in situ observations. The SLT from 1995–2015 is compared to the observed SLT from altimetry and 12 selected tide gauges (TGs) corrected for vertical land movement (VLM). The reconstructed estimate manifests the salinity-driven halosteric component as dominating the spatial SLT pattern with variations between −7 and 10 mm yr−1. The manometric SLT in comparison is estimated to be 1–2 mm yr−1 for most of the Arctic Ocean. The reconstructed SLT shows a larger sea level rise in the Beaufort Sea compared to altimetry, an issue that is also identified by previous studies. There is a TG-observed sea level rise in the Siberian Arctic in contrast to the sea level fall from the reconstructed and altimetric estimate. From 1995–2015 the reconstructed SLT agrees within the 68 % confidence interval with the SLT from observed altimetry in 87 % of the Arctic between 65∘ N and 82∘ N (R=0.50) and with 5 of 12 TG-derived (VLM-corrected) SLT estimates. The residuals are seemingly smaller than results from previous studies using GRACE estimates and modeled T–S data. The spatial correlation of the reconstructed SLT to altimetric SLT during the GRACE period (2003–2015) is R=0.38 and R=0.34/R=0.37 if GRACE estimates are used instead of the constructed manometric component. Thus, the reconstructed manometric component is suggested as a legitimate alternative to GRACE that can be projected into the past and future.

Comprehensive Test and Evaluation Analysis of Permeable Concrete (PC) Clogging by Using Steel Slag

In recent decade, researchers have more attention to water resource protection and forward the concept of sponge city construction. PC is becoming more and more popular as a rainwater management tool because of fast climate changes worldwide. In this experiment, PC specimens were prepared with steel slag as aggregate, and the targeted porosity of specimens was 15%, 20%, and 25% respectively, and the ratio of water to cement was 0.38, 0.4, and 0.42. The PC specimens under the 200 mm high head are the most severely blocked; 0.283 m/s high‐speed horizontal runoff appears after the rapid plugging stage later in the other two types of speed tests. With time, the plugging effect of the test specimen is almost the same; the clogging degree of the PC sample with the porosity of 25% is more obvious than that of other porosity test specimens. The PC with large porosity is more serious to clogging because the higher seepage velocity will enter the internal tunnel with higher penetration force, which increases the possibility of clogging. Tests have shown that, at different rainwater runoff head heights, the PC specimens under the 200 mm high head are the most severely blocked; 0.283 m/s high‐speed horizontal runoff appears after the rapid plugging stage later in the other two types of speed tests but over time. With time, the plugging effect of the test specimen was almost the same; the clogging degree of the permeable concrete sample with the porosity of 25% is more obvious than that of other porosity test specimens. While it is noticed that the compressive strength of the PC after clogging has decreased in the freeze‐thaw environment, the destruction process is faster than the unblocked test specimen.

Fast climatic changes place an endemic Canary Island macroalga at extinction risk

Global warming and ultraviolet radiation (UVR) affect marine organisms worldwide. However, we still lack knowledge about the consequences of these environmental changes to range-restricted macroalgae species, such as Gelidium canariense, a habitat-forming endemic of the Canary Islands. The aim of this study is to provide useful data for analyzing the conservation status of this endemic species. To do this, (1) we compared distributional data from 1987 with the data collected in 2008 and 2019 along the northern coast of Tenerife; (2) we assessed the variation in macroalgae assemblages dominated by G. canariense over the last decade on this same cost; and (3) we explored the correlation of these results with the actual trends of sea surface temperature (SST), air temperature at 2 m above the sea surface (T2m), UVR, and downward solar radiation (DSR). The results showed significant changes in the distribution of G. canariense in the last 30 years at Tenerife. More than 90% of its populations have declined. The endemic macroalgae have been replaced by the globally distributed species Pterocladiella capillacea at nearly all the sites studied. The cover of G. canariense and Gelidium arbuscula decreased significantly with increasing SST and T2m. Additionally, G. canariense is negatively related to the rise in UVR. These results highlight the vulnerability of both species of Gelidium to global warming and UVR, but especially of G. canariense. The drastic decline of this species reveals the need to upgrade its conservation status and implement protection measures to reduce the damage that predicted global change scenario may have to their relict populations.

About the Cover

Next article FreeAbout the CoverPDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinked InRedditEmailQR Code SectionsMoreThe cover image features a hatchling American alligator (Alligator mississippiensis) emerging from its nest. Like many non-mammalian vertebrates, the temperature that alligators experience during development determines their sex. Temperature-dependent sex determination (TSD) is a form of developmental plasticity that may provide insight into how taxa respond to fluctuating environments and extreme conditions that are predicted to intensify with ongoing climate change. However, the evolutionary drivers of TSD are unresolved for many species, including crocodilians. In this issue, S. L. Bock, M. D. Hale, T. R. Rainwater, P. M. Wilkinson, and B. B. Parrott (pp. 43–54) demonstrate that fluctuating versus constant temperature conditions have different effects on the juvenile phenotype of alligators, and that warmer temperatures produce males with greater residual yolk reserves and larger hatchling sizes. Variation in developmental costs at different incubation temperatures may therefore contribute to the evolution of TSD.Coastal ecosystems are naturally variable in important physical stressors like temperature, salinity, pH, and hypoxia. Understanding how species adapt to such fluctuating conditions should enable better predictions of the evolutionary responses of coastal communities to climate change. In their Introduction (pp. 1–3), the editors of the series—Patrick J. Krug, John P. Wares, and Jonathan D. Allen—argue for a broader study of plasticity and local adaptation in aquatic organisms in the context of a fast-changing climate. This symposium issue brings together contributions examining all life stages of freshwater, estuarine, and marine organisms and uses approaches ranging from genomic to experimental techniques to understand survival strategies in unpredictable versus stable environments.Credits: Photo of juvenile alligator, Benjamin B. Parrott, Odum School of Ecology, University of Georgia. Cover design, Matt Lang, University of Chicago Press. Next article DetailsFiguresReferencesCited by The Biological Bulletin Volume 241, Number 1August 2021Adaptive and Plastic Responses to Environmental Variation Published in association with the Marine Biological Laboratory Article DOIhttps://doi.org/10.1086/717022 Views: 304 © 2021 by The University of Chicago. All rights reserved.PDF download Crossref reports no articles citing this article.

A reconciled solution of Meltwater Pulse 1A sources using sea-level fingerprinting

The most rapid global sea-level rise event of the last deglaciation, Meltwater Pulse 1A (MWP-1A), occurred ∼14,650 years ago. Considerable uncertainty regarding the sources of meltwater limits understanding of the relationship between MWP-1A and the concurrent fast-changing climate. Here we present a data-driven inversion approach, using a glacio-isostatic adjustment model to invert for the sources of MWP-1A via sea-level constraints from six geographically distributed sites. The results suggest contributions from Antarctica, 1.3 m (0–5.9 m; 95% probability), Scandinavia, 4.6 m (3.2–6.4 m) and North America, 12.0 m (5.6–15.4 m), giving a global mean sea-level rise of 17.9 m (15.7–20.2 m) in 500 years. Only a North American dominant scenario successfully predicts the observed sea-level change across our six sites and an Antarctic dominant scenario is firmly refuted by Scottish isolation basin records. Our sea-level based results therefore reconcile with field-based ice-sheet reconstructions.

Phenotypic plasticity of European larch radial growth and wood density along a-1,000 m elevational gradient.

Phenotypic plasticity is a key mechanism for sedentary long-living species to adjust to changing environment. Here, we use mature Larix decidua tree-ring variables collected along an elevational transect in the French Alps to characterize the range of individual plastic responses to temperature. Stem cores from 821 mature Larix decidua trees have been collected from four plots distributed along a 1,000-m elevational gradient in a natural forest to build up individual linear reaction norms of tree-ring microdensity traits to temperature. The sign, magnitude and spread of variations of the slopes of the individual reaction norms were used to characterize variation of phenotypic plasticity among plots and traits. Results showed a large range of phenotypic plasticity (with positive and negative slopes) at each elevational plot and for each tree-ring variable. Overall, phenotypic plasticity tends to be larger but positive at higher elevation, negative at the warmer lower sites, and more variable in the center of the elevation distribution. Individual inter-ring reaction norm is a valuable tool to retrospectively characterize phenotypic plasticity of mature forest trees. This approach applied to Larix decidua tree-ring micro-density traits along an elevation gradient showed the existence of large inter-individual variations that could support local adaptation to a fast-changing climate.

Winter Oilseed Crop Canola in the Age of Fast Changing Climate

Canola is today the most widely cultivated Brassicaceae family crop species. Rape (canola) oil was a source of oil for lighting purposes in ancient times. Canola is now the second common oilseed crop in the world with greater than 12% of the world oil supply. The protein quantity and quality, and overall nutrient content of canola is quite good. Global demand for protein sources for human and animal consumption is rising with rapidly growing world population. Plant proteins are a good source for food processing as an alternative to animal proteins. Canola meal has a big potential to be used as a high protein food ingredient. Canola meal is the biodiesel industry byproduct and is abundant in major producing countries. During extracting canola oil, big quantities of meal are produced. Effect of climate change on agriculture or more specifically canola and its multidimensional bitoic and abiotic relations may sharply reduce global canola production especially in vulnerable regions. Climate change is influencing the growth period of the crops, crop growth, photosynthesis an dother importan tmetabolisms of plants, arable land acreages, soil fertility and incidence of biotic factors (pests, diseases and weeds).  Forest fires in the cold country Canada, where canola production is top in the world, may be a sign to us that 18,6 million tons of canola production on 8,3 million ha area may be under a threat. This which may effect trade, indstry and consumption of a major oilseed product. Oilseeds are an important backbone in global agricultural commodity trade and economy of countries. Canola has high oil content used as a food and fuel source and its oil process co-product meal is high in protein as a feed. Here in this review some aspects related to importance of seeds of canola and canola crop responce to selected stress factors are given below.

Antarctic krill fishery effects over penguin populations under adverse climate conditions: Implications for the management of fishing practices.

Fast climate changes in the western Antarctic Peninsula are reducing krill density, which along with increased fishing activities in recent decades, may have had synergistic effects on penguin populations. We tested that assumption by crossing data on fishing activities and Southern Annular Mode (an indicator of climate change in Antarctica) with penguin population data. Increases in fishing catch during the non-breeding period were likely to result in impacts on both chinstrap (Pygoscelis antarcticus) and gentoo (P. papua) populations. Catches and climate change together elevated the probability of negative population growth rates: very high fishing catch on years with warm winters and low sea ice (associated with negative Southern Annular Mode values) implied a decrease in population size in the following year. The current management of krill fishery in the Southern Ocean takes into account an arbitrary and fixed catch limit that does not reflect the variability of the krill population under effects of climate change, therefore affecting penguin populations when the environmental conditions were not favorable.

Amelioration of plant responses to drought under elevated CO2 by rejuvenating photosynthesis and nitrogen use efficiency: implications for future climate-resilient crops.

The contemporary global agriculture is beset with serious threats from diverse eco-environmental conditions causing decreases in crop yields by ~ 15%. These yield losses might increase further due to climate change scenarios leading to increased food prices triggering social unrest and famines. Urbanization and industrialization are often associated with rapid increases in greenhouse gases (GHGs) especially atmospheric CO2 concentration [(CO2)]. Increase in atmospheric [CO2] significantly improved crop photosynthesis and productivity initially which vary with plant species, genotype, [CO2] exposure time and biotic as well as abiotic stress factors. Numerous attempts have been made using different plant species to unravel the physiological, cellular and molecular effects of elevated [CO2] as well as drought. This review focuses on plant responses to elevated [CO2] and drought individually as well as in combination with special reference to physiology of photosynthesis including its acclimation. Furthermore, the functional role of nitrogen use efficiency (NUE) and its relation to photosynthetic acclimation and crop productivity under elevated [CO2] and drought are reviewed. In addition, we also discussed different strategies to ameliorate the limitations of ribulose-1,5-bisphosphate (RuBP) carboxylation and RuBP regeneration. Further, improved stomatal and mesophyll conductance and NUE for enhanced crop productivity under fast changing global climate conditions through biotechnological approaches are also discussed here. We conclude that multiple gene editing approaches for key events in photosynthetic processes would serve as the best strategy to generate resilient crop plants with improved productivity under fast changing climate.

“Seeing like a Professor” or Shifting Gears: University Temporality and the Pace of Transformation in Post-Soviet Russia

Over the past nearly 30 years, Russian universities have been buffeted by external forces necessitating attempts to adjust to a fast-changing academic climate, both globally and regionally. Based on informally structured interviews of university faculty of different age groups and ranks, academic fields and regions of the country conducted between 2012 and 2018, this essay examines what transpires in the life of a Russian university; how do professors evaluate change and how has the pace of university life been altered—such questions are addressed by revealing the connection between notions of academic freedom and temporality—the perceived ability to exert control over time at the university.

Environmental Fluctuations Drive Species' Competitive Success in Experimental Invasions

Climate change is presumed to increase both the number and frequency of fluctuations in environmental conditions. Fluctuations can affect the ecological and evolutionary processes that make species more successful competitors. For example, fluctuating conditions can create selection pressures for traits that are profitable in adaptation to fast climate change. On an ecological timescale, environmental fluctuations can facilitate species competitive success by reducing other species' population sizes. Climate change could then enhance species invasions into new areas if fluctuation-adapted invaders displace their native competitors in chancing environments. We tested experimentally whether fast environmental fluctuations, either past (on an evolutionary timescale) or present (on an ecological timescale) affect species competitive success. Bacteria that evolved in either constant or fluctuating temperature were set to compete with the dominant invader Serratia marcescens, which had also evolved in either constant or fluctuating temperature. Moreover, the competition experiments were conducted in environments with similarly constant or fluctuating thermal conditions. The results showed that temperature fluctuations during competition, i.e. on an ecological timescale, made the invader more successful. Surprisingly, we found that the invaders' or its competitor species' evolution in fluctuating environments did not affect the outcome of the competition. Our study highlights the importance of the present environmental fluctuations in promoting species' competitive success and potentially facilitating biological invasions.

Options and opportunities for manipulation of drought traits using endophytes in crops

Drought is a major cause of yield reduction in a wide range of crops. Under the fast-changing climate scenario, drought episodes are expected to be more frequent, further penalizing crop yields. There is a need to enhance crop adaptation to drought for sustained productivity. Attempts have been made to validate and manipulate drought-traits in crops with some degree of success. There are evidence to show that plant and its associated microbiome interact and modulate traits in host plants. From this context, efforts are being made to manipulate drought traits using endophytes. In this review, we highlight the importance of associating endophytes with drought traits and the relevance of endophyte mediated manipulation of traits for crop production under water limiting conditions.

Long-term quality and stability assessment of CryoSat-2 Ocean Data

Since 8 April 2010 ESA’s Earth Explorer mission CryoSat-2 has been measuring marine and land ice thickness variations with a dedicated altimeter. With the effects of a fast-changing climate becoming apparent, it is increasingly important to understand exactly how Earth’s ice fields are responding and regulate climate and sea level. It is therefore of utmost importance that the quality of the CryoSat-2 altimeter data meets the highest accuracy and precision level, not only over the ice caps and sea-ice surface but over the oceans as well. The SIRAL altimeter of CryoSat-2 is capable of measuring high-resolution geophysical parameters from the open ocean to the coast. In this paper, we validate the CryoSat-2 geophysical ocean product, Baseline-B (GOP). The analyses focus on long-term monitoring, validation, and cross-calibration of these ocean altimeter data with all the concurrent altimeter data in the Radar Altimeter Database System RADS and with independent in-situ tide gauge measurements from the Permanent Service for Mean Sea Level PSMSL. The objective is to evaluate the stability of the CryoSat-2 measurement system and the identification and explanation of biases and bias drifts. A persistent monitoring of these biases in time is important to establish the data’s usefulness for investigation of long-term sea level and ice topography/volume changes. The results constitute the final status of the GOP baseline-B product for use as essential climate variables. GOP ocean data has a - 6.3 ± 0.2 cm range bias w.r.t. to all calibrated satellites in RADS and a drift of 0.14 mm yr −1 w.r.t. Jason-2. GOP data has significant wave height and sea state biases close to that of the Jasons’, and seems to be better handling the LRM-SAR transitions than the RADS CryoSat-2 product. GOP data w.r.t. PSMSL tide gauge data has an average correlation of R = 0.83, a mean st. dev. of σ = 6.30 cm, and a drift of 0.11 mm yr −1 , equivalent to 40 Gt yr −1 ice sheet mass loss. It is concluded that GOP CryoSat-2 performs better than RADS CryoSat-2, which seems to suffer from a 480-day platform temperature cycle. GOP is also on a par with the altimeter data from the Jason reference missions, and well suited for ocean and climate studies.

Enhancement of resilience to climate variability and change through agroforestry practices in smallholder farming systems in Cameroon

The impacts of climate variability and change are being felt by various sectors of economic life, especially the agricultural sector. It is for this reason that this study sought to investigate how agro-ecological and climate-smart systems like agroforestry could contribute towards enhancing the resilience of the agricultural sector in general and smallholder farmers in particular, faced with the climate change menace in Cameroon. Household and field surveys were the main primary data collection methods. Findings showed that variability and changes in climate parameters were real, and a plethora of agroforestry practices categorized into agrosilvicultural, silvopastoral and agrosilvopastoral systems were practiced by smallholder farmers. Agroforestry products and services like food, fuelwood, building materials, and erosion control were identified by smallholder farmers as contributing towards the strengthening of their resilience to climate change impacts. The major groups of agroforestry tree/shrub species integrated on smallholder farm plots were fruit trees, fuelwood trees/shrubs and trees/shrubs used as building materials. Results from Chi square statistic, Kruskal–Wallis test, and logistic regression analysis (p < 0.05) revealed that agroforestry practices especially home gardens with animals, home gardens, trees on grazing lands, and coffee-based agroforestry played a significant positive role in enhancing smallholder farmers’ resilience to the impacts of climate variability and change. The study therefore recommends that agroforestry be prioritized in national and international policy formulations owing to its ability to enhance smallholder farmers’ resilience faced with a fast changing climate.

Regulatory implications of coral reef restoration and adaptation under a changing climate

Coral reef restoration is gaining considerable momentum globally in response to climate change and other anthropogenic impacts on coral reefs. In Australia, as part of the Reef Restoration and Adaptation Program (RRAP), a range of unconventional interventions are currently being investigated to help the Great Barrier Reef resist, repair and recover from climate change. Many of these interventions are based on innovative approaches, such as assisted evolution. The regulatory environment is likely to be critical in determining the feasibility and viability of reef restoration and adaptation interventions. It influences what, where and how to restore, who should be responsible for, engaged in, and benefit from restoration. This study explores the regulatory implications of proposed restoration and adaptation interventions in the context of the Great Barrier Reef. This includes mapping the existing regulatory and governance landscape, establishing an approach to account for regulatory requirements of restoration and adaptation interventions, and examining regulatory issues associated with their development and deployment. The study also scopes administrative capacity; i.e., the capacity of regulators in terms of resources and skills required to assess novel risks and impacts of reef restoration and adaptation interventions. It provides important insights that may prove useful for other jurisdictions, where ecosystem restoration and adaptation has become an imperative under a fast-changing climate.

Post-growth strategies can be more feasible than techno-fixes: Focus on working time

For sufficiently fast climate change mitigation, strategies once considered unthinkable have to be discussed. As negative-emission technologies and solar geoengineering are risky, social and economic innovations are needed as well. Working time reduction is a completely neglected strategy that needs urgent attention in climate–economy models and policy.

Estimation of Above Ground Biomass in a Tropical Mountain Forest in Southern Ecuador Using Airborne LiDAR Data

A reliable estimation of Above Ground Biomass (AGB) in Tropical Mountain Forest (TMF) is still complicated, due to fast-changing climate and topographic conditions, which modifies the forest structure within fine scales. The variations in vertical and horizontal forest structure are hardly detectable by small field plots, especially in natural TMF due to the high tree diversity and the inaccessibility of remote areas. Therefore, the present approach used remotely sensed data from a Light Detection and Ranging (LiDAR) sensor in combination with field measurements to estimate AGB accurately for a catchment in the Andes of south-eastern Ecuador. From the LiDAR data, information about horizontal and vertical structure of the TMF could be derived and the vegetation at tree level classified, differentiated between the prevailing forest types (ravine forest, ridge forest and Elfin Forest). Furthermore, topographical variables (Topographic Position Index, TPI; Morphometric Protection Index, MPI) were calculated by means of the high-resolution LiDAR data to analyse the AGB distribution within the catchment. The field measurements included different tree parameters of the species present in the plots, which were used to determine the local mean Wood Density (WD) as well as the specific height-diameter relationship to calculate AGB, applying regional scale modelling at tree level. The results confirmed that field plot measurements alone cannot capture completely the forest structure in TMF but in combination with high resolution LiDAR data, applying a classification at tree level, the AGB amount (Mg ha−1) and its distribution in the entire catchment could be estimated adequately (model accuracy at tree level: R2 &gt; 0.91). It was found that the AGB distribution is strongly related to ridges and depressions (TPI) and to the protection of the site (MPI), because high AGB was also detected at higher elevations (up to 196.6 Mg ha−1, above 2700 m), if the site is situated in depressions (ravine forest) and protected by the surrounding terrain. In general, highest AGB is stored in the protected ravine TMF parts, also at higher elevations, which could only be detected by means of the remote sensed data in high resolution, because most of these areas are inaccessible. Other vegetation units, present in the study catchment (pasture and subpáramo) do not contain large AGB stocks, which underlines the importance of intact natural forest stands.

Synechococcus plasticity under environmental changes.

Cyanobacteria are among the oldest photoautotrophic organisms on Earth, and have contributed to shaping the planet's biogeochemistry with their significant biomass and key metabolic activities. Synechococcus, the focus of this review, is one of the prevalent genera in the order Chroococcales, common in oceans and lakes and characterized by a coccoid unicellular or microcolony morphology. The evolution of its phycobilisomes is the key of the adaptation of this tiny photosynthetic cell to different light regimes and environmental conditions. Furthermore, Synechococcus strains are widely distributed from the equator to the poles, showing an extreme adaptability to high and low temperatures. Because of their structural plasticity and ecological adaptability, these cyanobacteria are particularly interesting in the current condition of fast climate change. Moreover, picocyanobacteria of the Synechococcus genus have a potentially vast impact on global cycles thanks to their significant role in the biogeochemical cycles of aquatic ecosystems. As increasing abundances are predicted for this genus worldwide, and in light of the connection between cyanobacteria and global change events, a better characterization of these organisms promises important and timely ecological insights. Here, I will summarize the morphological and genetic characteristics of Synechococcus strains and their distribution in freshwater lakes, also considering its marine counterpart.

Projected impact of climate change and chemical emissions on the water quality of the European rivers Rhine and Meuse: A drinking water perspective

Low river discharges of the rivers Rhine and Meuse are expected to occur more often and more prolonged in a changing climate. During these dry periods the dilution of point sources such as sewage effluents is reduced leading to a decline in chemical water quality. This study projects chemical water quality of the rivers Rhine and Meuse in the year 2050, based on projections of chemical emissions and two climate scenarios: moderate and fast climate change. It focuses on specific compounds known to be relevant to drinking water production, i.e. four pharmaceuticals, a herbicide and its metabolite and an artificial sweetener. Hydrological variability, climate change, and increased emission show a significant influence on the water quality in the Rhine and Meuse. The combined effect of changing future emissions of these compounds and reduced dilution due to climate change has leaded to increasing (peak) concentrations in the river water by a factor of two to four. Current water treatment efficiencies in the Netherlands are not sufficient to reduce these projected concentrations in drinking water produced from surface water below precautionary water target values. If future emissions are not sufficiently reduced or treatment efficiencies are not improved, these compounds will increasingly be found in drinking water, albeit at levels which pose no threat to human health.