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Recent studies have demonstrated that projected climate change will likely enhance nitrogen (N) and phosphorus (P) loss from farms and farmland, with the potential to worsen freshwater eutrophication. Here, we investigate the relative importance of the climate and land use drivers of nutrient loss in nine study catchments in Europe and a neighboring country (Turkey), ranging in area from 50 to 12,000 km2 . The aim was to quantify whether planned large-scale, land use change aimed at N and P loss reduction would be effective given projected climate change. To this end, catchment-scale biophysical models were applied within a common framework to quantify the integrated effects of projected changes in climate, land use (including wastewater inputs), N deposition, and water use on river and lake water quantity and quality for the mid-21st century. The proposed land use changes were derived from catchment stakeholder workshops, and the assessment quantified changes in mean annual N and P concentrations and loads. At most of the sites, the projected effects of climate change alone on nutrient concentrations and loads were small, whilst land use changes had a larger effect and were of sufficient magnitude that, overall, a move to more environmentally focused farming achieved a reduction in N and P concentrations and loads despite projected climate change. However, at Beyşehir lake in Turkey, increased temperatures and lower precipitation reduced water flows considerably, making climate change, rather than more intensive nutrient usage, the greatest threat to the freshwater ecosystem. Individual site responses did however vary and were dependent on the balance of diffuse and point source inputs. Simulated lake chlorophyll-a changes were not generally proportional to changes in nutrient loading. Further work is required to accurately simulate the flow and water quality extremes and determine how reductions in freshwater N and P translate into an aquatic ecosystem response.

There is evidence that both omega-3 polyunsaturated fatty acids (n-3 PUFAs) and choline can influence sports performance, but information establishing their combined effects when given in the form of krill oil during power training protocols is missing. The purpose of this study was therefore to characterize n-3 PUFA and choline profiles after a one-hour period of high-intensity physical workout after 12 weeks of supplementation. Thirty-five healthy power training athletes received either 2.5 g/day of Neptune krill oilTM (550 mg EPA/DHA and 150 mg choline) or olive oil (placebo) in a randomized double-blind design. After 12 weeks, only the krill oil group showed a significant HS-Omega-3 Index increase from 4.82 to 6.77% and a reduction in the ARA/EPA ratio (from 50.72 to 13.61%) (p < 0.001). The krill oil group showed significantly higher recovery of choline concentrations relative to the placebo group from the end of the first to the beginning of the second exercise test (p = 0.04) and an 8% decrease in total antioxidant capacity post-exercise versus 21% in the placebo group (p = 0.35). In conclusion, krill oil can be used as a nutritional strategy for increasing the HS-Omega-3 Index, recover choline concentrations and address oxidative stress after intense power trainings.

Ecoevolutionary dynamics of the gut microbiota at the macroscale level, that is, in across-species comparisons, are largely driven by ecological variables and host genotype. The repeated explosive radiations of African cichlid fishes in distinct lakes, following a dietary diversification in a context of reduced genetic diversity, provide a natural setup to explore convergence, divergence and repeatability in patterns of microbiota dynamics as a function of the host diet, phylogeny and environment. Here we characterized by 16S rRNA amplicon sequencing the gut microbiota of 29 cichlid species from two distinct lakes/radiations (Tanganyika and Barombi Mbo) and across a broad dietary and phylogenetic range. Within each lake, a significant deviation between a carnivorous and herbivorous lifestyle was found. Herbivore species were characterized by an increased bacterial taxonomic and functional diversity and converged in key compositional and functional community aspects. Despite a significant lake effect on the microbiota structure, this process has occurred with remarkable parallels in the two lakes. A metabolic signature most likely explains this trend, as indicated by a significant enrichment in herbivores/omnivores of bacterial taxa and functions associated with fiber degradation and detoxification of plant chemical compounds. Overall, compositional and functional aspects of the gut microbiota individually and altogether validate and predict main cichlid dietary habits, suggesting a fundamental role of gut bacteria in cichlid niche expansion and adaptation.

Este artículo contiene 17 páginas, 5 tablas, 2 figuras., Gipuzkoa (Basque Country, North Spain) is an industrial region where investments in sanitation and wastewater treatment have improved water quality and partially recovered river biological communities. However, further technological improvements are unlikely. Our objective was to assess whether in-stream self-purification may contribute to improvement of the trophic state of rivers. We propose an integrative approach to assessing river water quality, which diagnoses problems, identifies likely causes and prescribes solutions. We first analysed the loads of nutrients transported by Gipuzkoa rivers and compared them with the potential nutrient uptake rates (estimated from published empirical regressions). In reaches where both of them were within one order of magnitude, we considered that the self-purification capacity of river channels may influence nutrient concentrations. Then, we selected some river reaches where no other water quality problems beyond nutrient concentrations occurred and ran the expert system STREAMES 1.0 to diagnose the problems and detect their causes. The studied reaches di ered in their problems and in their potential solutions. We empirically determined nutrient retention in two streams by means of mass balances and slug nutrient additions. We detected large di erences in retention capacity between reaches and siltation as one of the main problems a ecting the self-purification capacity of the study streams. Finally, we used STREAMES 1.0 to identify potential solutions to specific river sections. The results obtained so far point towards an important potential of in-stream bioreactive capacity to reduce nutrient loads and to specific restoration activities that may improve the functionality and trophic status of the streams in Gipuzkoa., This research was funded by the Department of HydraulicWorks, Province Government of Gipuzkoa., We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI)

Background: Caloric restriction induces mitochondrial biogenesis and improves physical fitness in rodents. We aimed to provide evidence of how caloric restriction affects the body composition and physical performance of trained athletes and to evaluate the possible impact of an every-other-day feeding diet on nutritional deficiencies of micronutrients and essential fatty acids. Methods: The study was performed with 12 healthy male athletes by carrying out a 33% caloric restriction with respect to their usual diet. Athletes performed a maximal exercise stress test both before and after the caloric restriction period. Blood samples were taken before and after the caloric restriction at basal conditions and 30 min post-exercise. Although energy intake was reduced by about 33%, the contribution of carbohydrates, proteins, and lipids to total energy intake during the caloric restriction was similar to the original diet. Results: The caloric restriction reduced the daily specific micronutrient intake to values lower than 90% of recommended dietary allowances. No effects were observed in blood parameters related to iron metabolism and tissue damage, glucose levels, lipid profiles, or erythrocyte fatty acid composition. In addition, oxidative damage markers decreased after the nutritional intervention. The caloric restriction intervention significantly reduced body weight and trunk, arm, and leg weights; it also caused a decrease in fat and lean body mass, the energy expenditure rate when performing a maximal exercise stress test, and the energy cost to run one meter at various exercise intensities. Furthermore, the intervention ameliorated the onset of the anaerobic phase of exercise. Conclusion: A caloric restriction improves athletes' performance and energy efficiency, but reduces the daily intake of micronutrients; so, when caloric restriction programs are implemented micronutrient supplementation should be considered., Accion Estrategica en Salud del Ministerio de Ciencia e Innovacion DPS2008-07033-C03-03, Programme of Promotion of Biomedical Research and Health Sciences, Projects 11/01791, Red Predimed-RETIC RD06/0045/1004, CIBEROBN CB12/03/30038 and Balearic Island Government and FEDER funds (35/2011 and 23/2012). We hereby acknowledge the PhD grant provided by the University of the Balearic Islands.

n-3-polyunsaturated fatty acids and polyphenols are potential key factors for the treatment and prevention of chronic inflammation associated to ageing and non-communicable diseases. The aim was to analyse effects of an almond and olive oil beverage enriched with alpha-tocopherol and docosahexaenoic, exercise and age on inflammatory plasma markers, and immune gene expression in peripheral blood mononuclear cells (PBMCs). Five young and five senior athletes who were supplemented for five weeks with a functional beverage performed a stress test under controlled conditions before and after beverage supplementation. Blood samples were taken immediately before and 1 h after each test. Plasma, erythrocytes and PBMCs were isolated. Beverage supplementation increased plasmatic Tumour Necrosis Factor alpha (TNF alpha) levels depending on age and exercise. Exercise increased plasma non esterified fatty acids (NEFAs), soluble Intercellular adhesion molecule 3 (sICAM3) and soluble L-selectin (sL-Selectin), and this increase was attenuated by the supplementation. Exercise increased PGE2 plasma levels in supplemented young and in senior placebo athletes. Exercise increased NFk beta-activated levels in PBMCs, which are primed to a pro-inflammatory response increasing pro-inflammatory genes expression after the exercise mainly in the young group after the supplementation. The functional beverage supplementation to young athletes enhances a pro-inflammatory circulating environment in response to the exercise that was less evident in the senior group., Accion Estrategica en Salud del Ministerio de Ciencia e Innovacion DPS2008-07033-C03-03, Programme of Promotion of Biomedical Research and Health Sciences, Projects 11/01791, Red Predimed-RETIC RD06/0045/1004, CIBEROBN CB12/03/30038 and Balearic Island Government and FEDER funds (35/2011 and 23/2012). We hereby acknowledge the PhD grant provided (to X Capo) by the University of the Balearic Islands.

Rivers in developed regions are under significant stress due to nutrient enrichment generated mainly by human activities. Excess nitrogen and phosphorus emissions are the product of complex dynamic systems influenced by various factors such as demographic, socio-economic and technological development. Using a Catalan river catchment, La Tordera (North-East of Spain), as a case study of an integrated and interdisciplinary environmental assessment of nutrient flows, we present and discuss the development of narrative socio-economic scenarios through a participatory process for the sustainable management of the anthropogenic sources of nutrients, nitrogen and phosphorus. In this context, scenarios are an appropriate tool to assist nutrient emissions modelling, and to assess impacts, possible pathways for socio-economic development and associated uncertainties. Evaluated against the 1993–2003 baseline period, scenarios target the 2030 horizon, i.e. through the implementation process of the Water Framework Directive (Directive 2000/60/EC). After a critical examination of the methodology used in the participatory development of socio-economic scenarios, we present four possible futures (or perspectives) for the Catalan river catchment conceived by stakeholders invited to a workshop. Keys to the success of such a participatory process were trust, which enhanced openness, and disagreements, which fostered the group's creativity for scenario development. The translation of narrative socio-economic scenarios into meaningful nutrient emission scenarios is also discussed. By integrating findings of natural sciences and socio-economic analysis, we aim to assist decision makers and stakeholders in evaluating optimal management strategies for the anthropogenic sources of nitrogen and phosphorus.

18 páginas, 3 figuras, 4 tablas, Distribution of aquatic macrophytes in lakes is related to geographical, morphological, catchment and water chemistry variables as well as human impacts, which modify the original environment. Here, we aim at building statistical models to establish the ecological niches of 11 aquatic macrophytes (10 different phanerogams and the genus Nitella) from oligotrophic soft-water lakes and infer their ecological requirements and environmental constraints at the southernmost limit of their distribution. Macrophyte occurrence and environmental variables were obtained from 86 non-exploited oligotrophic soft-water lakes from the Pyrenees (Southern Europe; 42°50´N, 1°00´E); macrophytes inhabited 55 of these lakes. Optimum ranges and macrophyte occurrence were predicted in relation to 18 geographical, morphological, catchment and water chemistry variables using univariate and multivariate logistic models. Lakes at low altitude, in vegetated catchments and with low water concentration of NO3 – and SO4 –2, were the most suitable to host macrophytes. In general, individual species of aquatic macrophytes showed clear patterns of segregation along conductivity and pH gradients, although the specific combination of variables selected in the best models explaining their occurrence differed among species. Based on the species response to pH and conductivity, we found Isoetes lacustris have its optimum in waters with low conductivity and pH (i.e., negative monotonic response). In contrast, Callitriche palustris, Ranunculus aquatilis, Subularia aquatica, Nitella spp., and Myriophyllum alterniflorum showed an optimum at intermediate values (i.e. unimodal response), whereas Potamogeton berchtoldii, Potamogeton alpinus, and Ranunculus trichophyllus as species had their optimum at relatively high water pH and conductivity (i.e. positive monotonic response). This pattern has been observed in other regions for the same species, although with different optima and tolerance ranges. The parsimonious models developed here allowed us to explore niche requirements for each species and to predict the occurrence of macrophytes and of individual species in any particular lake by using only few, easily measured environmental variables. This is of interest to forecast possible changes related to global change and to assist managers in making conservation, management and restoration decisions., Financial support was provided by the Spanish Ministry of Science and Innovation through funding of the AQUAREST project (ref: OAPN 212/2010).

When ascending to a higher altitude, changes in air density and oxygen levels affect the way in which explosive actions are executed. This study was designed to compare the effects of acute exposure to real or simulated moderate hypoxia on the dynamics of the force-velocity relationship observed in bench press exercise. Twenty-eight combat sports athletes were assigned to two groups and assessed on two separate occasions: G1 (n = 17) in conditions of normoxia (N1) and hypobaric hypoxia (HH) and G2 (n = 11) in conditions of normoxia (N2) and normobaric hypoxia (NH). Individual and complete force-velocity relationships in bench press were determined on each assessment day. For each exercise repetition, we obtained the mean and peak velocity and power shown by the athletes. Maximum power (Pmax) was recorded as the highest Pmean obtained across the complete force-velocity curve. Our findings indicate a significantly higher absolute load linked to Pmax (~3%) and maximal strength (1RM) (~6%) in G1 attributable to the climb to altitude (P, This study has been supported by a Grant from the Ministry of education, culture and Sport of Spain, Reference 14/UPB10/07.

Despite an array of significant technological advances, effluents from wastewater treatment plants (WWTPs) generate abrupt physical and chemical discontinuities along the fluvial continuum. These discontinuities not only alter the water quality, but also significantly affect fluvial ecosystem structure and function. In particular, WWTP effluents increase nutrient concentrations and introduce toxic substances, including emergent pollutants, to the fluvial ecosystems. There is abundant evidence that these changes affect stream communities. Fewer studies, however, have examined the influence of WWTP inputs on the hydrologic and nutrient availability regimes. Yet, shifts in these regimes can have clear implications for the stream ecosystem function. This knowledge is of critical relevance for stream management as it provides insights on integrative properties of trophic state, energy transfer, and material cycling at the ecosystem level. WWTP effects on fluvial ecosystems are expected to become more exacerbated under water scarcity conditions, which are characteristic of arid and semiarid regions such as the Mediterranean region. Under these conditions, streams receiving point source inputs may turn into islands of permanent flow within a highly intermittent fluvial network. This has implications not only locally at the reach scale but also at the catchment scale. Within this context, both plant operation and fluvial management may be critical to preserve the ecological integrity of these aquatic ecosystems at the same time that a balance is met with societal demand for high quality water resources. This chapter aims to review current knowledge on this topic, with major emphasis on nutrient loads and in-stream nutrient retention, and to discuss its implications within the context of actual and future scenarios of water scarcity conditions.

A space-for-time substitution approach was used to evaluate potential effects of climate change on stream nutrient uptake by examining the relationship between stream environmental parameters and carbon (C), nitrogen (N) and phosphorus (P) uptake along an altitudinal gradient. The study was carried out in 14 streams located in the Central Pyrenees (NE Spain) draining calcareous catchments that cover an altitudinal range of 700―2,100ma.s.l. In these streams, uptake of inorganic (soluble reactive phosphorus (SRP), ammonium and nitrate) and organic (acetate and glycine) nutrients was estimated. Additionally, several physical, chemical and biological parameters were measured. Results showed higher uptake for both SRP, a potentially limiting nutrient in these streams, and glycine, a labile source of dissolved organic N, than for the rest of the nutrients. Uptake of SRP, nitrate, glycine and acetate varied along stream environmental gradients associated with changes in stream hydromorphology, SRP availability and epilithic biomass. However, these gradients did not vary with altitude. These results indicate that climate change effects on stream nutrient uptake are more likely to be driven by indirect effects on hydromorphology and nutrient availability induced by shifts in the precipitation and run-off regime than by direct modifications in the thermal regime.

11 páginas, 8 figuras, 3 tablas., The nutrient enrichment of rivers and its consequences are among the most severe water quality problems in Europe, causing eutrophication and other problems. The decision-making processes involved in the management of these problems require extensive human expertise from people who deal directly with day-to-day stream problems, as well as empiricalknowledge based on scientific research. This means that eutrophication is a complex problem, the optimal management of which requires an integrated and multidisciplinary approach. This approach can be taken using aKnowledge-Based System (KBS) built upon the concepts and methods of human reasoning. Accordingly, aKBS was developed within the STREAMES project. In this KBS most of the knowledge needed for managing eutrophication problems was organised and structured in the form of a decision tree (DT). The methodology specially developed to build this KBS, as well as the internal structure of the eutrophication decision tree, is presented here. The good DT obtained led to consider the KBSa suitable tool to support the management of eutrophication., European Commission (EVK1-CT-2000-00081, STREAMES project).

11 Páginas ; 6 Figuras ; 3 Tablas, This study examined the effect of increasing in-channel leaf standing stocks on hydrologic transient storage and nutrient retention in a Mediterranean mountain stream. A flood at the end of the leaf fall period provided the opportunity to examine the effect of abrupt removal of much of the leaf material. Twenty-one chloride additions were performed from October to December 2004. In 13 of these, we also added ammonium and phosphate to estimate nutrient uptake lengths and uptake velocities to assess nutrient retention. The one-dimensional transport with inflow and storage (OTIS) model was used to estimate transient water storage parameters. Although discharge remained constant during leaf fall, water residence time increased because of in-channel litter accumulation, as did nutrient uptake velocity. Flooding reduced leaf benthic standing stocks by 65% and dramatically altered hydraulic and nutrient retention properties of the channel. After recession, the stream rapidly recovered in terms of nutrient retention, especially for phosphate. Abrupt changes in discharge under flood conditions largely determined the variability in stream nutrient retention. However, leaf litter inputs played an important role in nutrient dynamics during constant flow. Because both the flood regime and the timing of leaf fall are being regionally altered by climate change, our results have implications for stream nutrient dynamics under climate change scenarios., Financial support was provided by the European Union through the EURO-LIMPACS project (ref: GOCE-CT-2003- 505540, www.eurolimpacs.ucl.ac.uk) and by the Spanish Ministry of Education and Science through RENITRAC (ref: REN2002- 03592/HID) and NICON (ref: CGL2005-07362-C02) projects. D. von Schiller was supported by an I3P PhD scholarship from the Spanish Council for Scientific Research (CSIC). Limnol. Oceanogr., 53(2), 2008, 631–641 E 2008, by the American Society of Limnology and Oceanography, Inc. 631

Background Strenuous exercise has been classically associated to immune-suppression and consequently to an increased risk of infections, especially at the upper respiratory tract. The administration of dietary nucleotides has been demonstrated useful to maintain the immune function in situations of stress and thus could be an appropriate strategy to counteract the decline of the immune function associated to strenuous exercise. The aim of the present study was to asses the impact of a specific nucleotide formulation (Inmunactive®) on the markers of immune function of athletes after a heavy exercise bout under cold conditions. Methods Twenty elite male taekwondo athletes were randomly divided into two groups of 10 subjects that were supplemented with placebo (P) or Inmunactive (I) at 480 mg/day during 30 days. At baseline (day 0) and after 4 wk of supplementation (day 30) each subject undertook an exhaustion exercise test using a cycloergometer. Skin temperature, core temperature, heart rate, lactate concentration and rating of perceived exertion (RPE) were recorded during the test. Blood and saliva samples were obtained before and after each exercise test for determination of blood cell concentrations, PHA-stimulated lymphocyte proliferation (PHA-LP) and salivary immunoglobulin A (SIgA). Results Exercise tests induced neutrophilia and reduction in lymphocyte blood counts on day 0 and on day 30 in both groups. However, the I group exhibited a faster recovery from the lymphopenic response than the P group, so that lymphocyte levels were higher after 150 min (P