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Model projections show that production of high-value products from microalgae could be profitable nowadays and commodities will become profitable within 10 years.

Integrated multitrophic aquaculture (IMTA) is a versatile technology emerging as an ecological and sustainable solution for traditional monoculture aquacultures in terms of effluent treatment. Nevertheless, IMTA is still poorly applied in aquaculture industry due to, among other reasons, the lack of effective, low-investment and low-maintenance solutions. In this study, one has developed a practical and low maintenance IMTA-pilot system, settled in a semi-intensive coastal aquaculture. The optimisation and performance of the system was validated using Ulva spp., a macroalgae that naturally grows in the fishponds of the local aquaculture. Several cultivation experiments were performed at lab-scale and in the IMTA-pilot system, in static mode. The specific growth rate (SGR), yield, nutrient removal, N and C enrichment, protein and pigment content were monitored. Ulva spp. successfully thrived in effluent from the fish species sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax) production tanks and significantly reduced inorganic nutrient load in the effluent, particularly, NH4+, PO43− and NO3−. The enrichment of nitrogen in Ulva spp.’s tissues indicated nitrogen assimilation by the algae, though, the cultivated Ulva spp. showed lower amounts of protein and pigments in comparison to the wild type. This study indicates that the designed IMTA-pilot system is an efficient solution for fish effluent treatment and Ulva spp., a suitable effluent remediator.

Harmful Algal Blooms (HAB) are complex to manage due to their intermittent nature and their severe impact on the economy and human health. The conditions which promote HAB have not yet been fully explained, though climate change and anthropogenic intervention are pointed as significant factors. The rise of water temperature, the opening of new sea canals and the introduction of ship ballast waters all contribute to the dispersion and establishment of toxin-producing invasive species that promote the settling of emergent toxins in the food-chain. Tetrodotoxin, ciguatoxin, palytoxin and cyclic imines are commonly reported in warm waters but have also caused poisoning incidents in temperate zones. There is evidence that monitoring for these toxins exclusively in bivalves is simplistic and underestimates the risk to public health, since new vectors have been reported for these toxins and as well for regulated toxins such as PSTs and DSTs. In order to avoid public health impacts, there is a need for adequate monitoring programs, a need for establishing appropriate legislation, and a need for optimizing effective methods of analysis. In this review, we will compile evidence concerning emergent marine toxins and provide data that may indicate the need to restructure the current monitoring programs of HAB.

Impact of drought under enriched CO2 atmosphere on ecophysiological and leaf metabolic response of the sub-mediterranean Q. pyrenaica oak was studied. Seedlings growing in climate chamber were submitted to moderate drought (WS) and well-watered (WW) under ambient ([CO2]amb =400 ppm) or CO2 enriched atmosphere ([CO2]enr =800 ppm). The moderate drought endured by seedlings brought about a decrease in leaf gas exchange. However, net photosynthesis (Anet) was highly stimulated for plants at [CO2]enr. There was a decrease of the stomatal conductance to water vapour (gwv) in response to drought, and a subtle trend to be lower under [CO2]enr. The consequence of these changes was an important increase in the intrinsic leaf water use efficiency (WUEi). The electron transport rate (ETR) was almost a 20 percent higher in plants at [CO2]enr regardless drought endured by seedlings. The ETR/Anet was lower under [CO2]enr, pointing to a high capacity to maintain sinks for the uptake of extra carbon in the atmosphere. Impact of drought on the leaf metabolome, as a whole, was more evident than that from [CO2] enrichment of the atmosphere. Changes in pool of non-structural carbohydrates were observed mainly as a consequence of water deficit including increases of fructose, glucose, and proto-quercitol. Most of the metabolites affected by drought back up to levels of non-stressed seedlings after rewetting (recovery phase). It can be concluded that carbon uptake was stimulated by [CO2]enr, even under the stomatal closure that accompanied moderate drought. In the last, there was a positive effect in intrinsic water use efficiency (WUEi), which was much more improved under [CO2]enr. Leaf metabolome was little responsible and some few metabolites changed mainly in response to drought, with little differences between [CO2] growth conditions.

Combler le fossé entre les prévisions des modèles climatiques à échelle grossière et la réalité climatique à échelle fine des espèces est un enjeu clé de la recherche en biologie du changement climatique. Bien qu'il soit maintenant bien connu que la plupart des organismes ne connaissent pas les conditions climatiques enregistrées dans les stations météorologiques, il existe peu d'informations sur les écarts entre les microclimats et les températures interpolées mondiales utilisées dans les modèles de répartition des espèces, et leurs conséquences sur les performances des organismes. Pour résoudre ce problème, nous avons examiné l'hétérogénéité spatio-temporelle à échelle fine des températures de l'air, du couvert végétal et du sol des paysages agricoles des Andes équatoriennes et les avons comparés aux prévisions des grilles climatiques interpolées mondiales. Des séries temporelles de températures ont été mesurées dans l'air, la canopée et le sol pour 108 localités à trois altitudes et analysées à l'aide de la transformée de Fourier. Les écarts entre les températures locales et les grilles interpolées mondiales et leurs implications pour la performance des ravageurs ont ensuite été cartographiés et analysés à l'aide de la boîte à outils statistique SIG. Nos résultats ont montré que les prévisions globales interpolées surestiment de 77,5±10 % et sous-estiment de 82,1±12 % les températures locales minimales et maximales de l'air enregistrées dans la grille étudiée. Des modifications supplémentaires de la température de l'air local étaient dues au tamponnage thermique du couvert végétal (de − 2,7°K pendant la journée à 1,3°K pendant la nuit) et des sols (de −4,9°K pendant la journée à 6,7°K pendant la nuit) avec un effet significatif de la phénologie des cultures sur l'effet tampon. Ces écarts entre les températures interpolées et locales ont fortement affecté les prévisions de la performance d'un ravageur ectothermique des cultures, car les températures interpolées prédisaient des taux de croissance des ravageurs 2,3 à 4,3 fois inférieurs à ceux prédits par les températures locales. Cette étude fournit des informations quantitatives sur la limitation des données climatiques à échelle grossière pour capturer la réalité de l'environnement climatique vécu par les organismes vivants. Dans les régions très hétérogènes telles que les montagnes tropicales, il convient donc de faire preuve de prudence lors de l'utilisation de modèles mondiaux pour déduire des processus biologiques à l'échelle locale. Cerrar la brecha entre las predicciones de los modelos climáticos a escala gruesa y la realidad climática a escala fina de las especies es un tema clave de la investigación en biología del cambio climático. Si bien ahora es bien sabido que la mayoría de los organismos no experimentan las condiciones climáticas registradas en las estaciones meteorológicas, hay poca información sobre las discrepancias entre los microclimas y las temperaturas globales interpoladas utilizadas en los modelos de distribución de especies, y sus consecuencias para el rendimiento de los organismos. Para abordar este problema, examinamos la heterogeneidad espaciotemporal a escala fina en las temperaturas del aire, el dosel de los cultivos y el suelo de los paisajes agrícolas en los Andes ecuatorianos y los comparamos con las predicciones de las redes climáticas interpoladas globales. Las series temporales de temperatura se midieron en aire, dosel y suelo para 108 localidades a tres altitudes y se analizaron mediante la transformada de Fourier. Las discrepancias entre las temperaturas locales frente a las redes interpoladas globales y sus implicaciones para el rendimiento de las plagas se mapearon y analizaron utilizando una caja de herramientas estadísticas SIG. Nuestros resultados mostraron que las predicciones interpoladas globales sobreestiman en un 77.5±10% y subestiman en un 82.1±12% las temperaturas mínimas y máximas locales del aire registradas en la cuadrícula estudiada. Las modificaciones adicionales de las temperaturas locales del aire se debieron al amortiguamiento térmico de las copas de las plantas (de -2,7 ° K durante el día a 1,3 ° K durante la noche) y los suelos (de -4,9 ° K durante el día a 6,7 ° K durante la noche) con un efecto significativo de la fenología de los cultivos en el efecto amortiguador. Estas discrepancias entre las temperaturas interpoladas y locales afectaron fuertemente las predicciones del rendimiento de una plaga de cultivo ectotérmico, ya que las temperaturas interpoladas predijeron tasas de crecimiento de plagas 2.3–4.3 veces más bajas que las predichas por las temperaturas locales. Este estudio proporciona información cuantitativa sobre la limitación de los datos climáticos a escala aproximada para capturar la realidad del entorno climático experimentado por los organismos vivos. Por lo tanto, en regiones altamente heterogéneas como las montañas tropicales, se debe tener precaución al utilizar modelos globales para inferir procesos biológicos a escala local. Bridging the gap between the predictions of coarse-scale climate models and the fine-scale climatic reality of species is a key issue of climate change biology research. While it is now well known that most organisms do not experience the climatic conditions recorded at weather stations, there is little information on the discrepancies between microclimates and global interpolated temperatures used in species distribution models, and their consequences for organisms' performance. To address this issue, we examined the fine-scale spatiotemporal heterogeneity in air, crop canopy and soil temperatures of agricultural landscapes in the Ecuadorian Andes and compared them to predictions of global interpolated climatic grids. Temperature time-series were measured in air, canopy and soil for 108 localities at three altitudes and analysed using Fourier transform. Discrepancies between local temperatures vs. global interpolated grids and their implications for pest performance were then mapped and analysed using GIS statistical toolbox. Our results showed that global interpolated predictions over-estimate by 77.5±10% and under-estimate by 82.1±12% local minimum and maximum air temperatures recorded in the studied grid. Additional modifications of local air temperatures were due to the thermal buffering of plant canopies (from −2.7°K during daytime to 1.3°K during night-time) and soils (from −4.9°K during daytime to 6.7°K during night-time) with a significant effect of crop phenology on the buffer effect. This discrepancies between interpolated and local temperatures strongly affected predictions of the performance of an ectothermic crop pest as interpolated temperatures predicted pest growth rates 2.3–4.3 times lower than those predicted by local temperatures. This study provides quantitative information on the limitation of coarse-scale climate data to capture the reality of the climatic environment experienced by living organisms. In highly heterogeneous region such as tropical mountains, caution should therefore be taken when using global models to infer local-scale biological processes. يعد سد الفجوة بين تنبؤات النماذج المناخية ذات النطاق الخشن والواقع المناخي الدقيق للأنواع قضية رئيسية في أبحاث البيولوجيا المتعلقة بتغير المناخ. في حين أنه من المعروف الآن أن معظم الكائنات الحية لا تعاني من الظروف المناخية المسجلة في محطات الطقس، إلا أن هناك القليل من المعلومات حول التناقضات بين المناخات الدقيقة ودرجات الحرارة العالمية المستكملة المستخدمة في نماذج توزيع الأنواع، وعواقبها على أداء الكائنات الحية. لمعالجة هذه المشكلة، قمنا بفحص عدم التجانس الزماني المكاني الدقيق في الهواء ومظلة المحاصيل ودرجات حرارة التربة للمناظر الطبيعية الزراعية في جبال الأنديز الإكوادورية وقارناها بتنبؤات الشبكات المناخية العالمية المستكملة. تم قياس السلاسل الزمنية لدرجة الحرارة في الهواء والمظلة والتربة لـ 108 موقعًا على ثلاثة ارتفاعات وتم تحليلها باستخدام تحويل فورييه. ثم تم رسم خرائط التناقضات بين درجات الحرارة المحلية مقابل الشبكات العالمية المستكملة وآثارها على أداء الآفات وتحليلها باستخدام مجموعة الأدوات الإحصائية لنظم المعلومات الجغرافية. أظهرت نتائجنا أن التنبؤات العالمية المستكملة تزيد عن التقديرات بنسبة 77.5±10 ٪ وتقل عن التقديرات بنسبة 82.1±12 ٪ من الحد الأدنى المحلي والحد الأقصى لدرجات حرارة الهواء المسجلة في الشبكة المدروسة. كانت التعديلات الإضافية في درجات حرارة الهواء المحلية بسبب التخزين المؤقت الحراري لمظلات النباتات (من - 2.7 درجة كلفن خلال النهار إلى 1.3 درجة كلفن خلال الليل) والتربة (من - 4.9 درجة كلفن خلال النهار إلى 6.7 درجة كلفن خلال الليل) مع تأثير كبير لظاهرة المحاصيل على تأثير العازل. أثرت هذه التناقضات بين درجات الحرارة المستكملة والمحلية بشدة على التنبؤات بأداء آفة المحاصيل خارجة الحرارة حيث تنبأت درجات الحرارة المستكملة بمعدلات نمو الآفات 2.3–4.3 مرة أقل من تلك التي تنبأت بها درجات الحرارة المحلية. توفر هذه الدراسة معلومات كمية عن محدودية البيانات المناخية ذات النطاق الخشن لالتقاط واقع البيئة المناخية التي تعاني منها الكائنات الحية. في المناطق غير المتجانسة للغاية مثل الجبال الاستوائية، يجب توخي الحذر عند استخدام النماذج العالمية لاستنتاج العمليات البيولوجية على المستوى المحلي.

All climate change scenarios predict an increase in both global temperature means and the magnitude of seasonal and diel temperature variation. The nonlinear relationship between temperature and biological processes means that fluctuating temperatures lead to physiological, life history, and ecological consequences for ectothermic insects that diverge from those predicted from constant temperatures. Fluctuating temperatures that remain within permissive temperature ranges generally improve performance. By contrast, those which extend to stressful temperatures may have either positive impacts, allowing repair of damage accrued during exposure to thermal extremes, or negative impacts from cumulative damage during successive exposures. We discuss the mechanisms underlying these differing effects. Fluctuating temperatures could be used to enhance or weaken insects in applied rearing programs, and any prediction of insect performance in the field—including models of climate change or population performance—must account for the effect of fluctuating temperatures.

AbstractA better understanding of how climate affects growth in tree species is essential for improved predictions of forest dynamics under climate change. Long-term climate averages (mean climate) and short-term deviations from these averages (anomalies) both influence tree growth, but the rarity of long-term data integrating climatic gradients with tree censuses has so far limited our understanding of their respective role, especially in tropical systems. Here, we combined 49 years of growth data for 509 tree species across 23 tropical rainforest plots along a climatic gradient to examine how tree growth responds to both climate means and anomalies, and how species functional traits mediate these tree growth responses to climate. We showed that short-term, anomalous increases in atmospheric evaporative demand and solar radiation consistently reduced tree growth. Drier forests and fast-growing species were more sensitive to water stress anomalies. In addition, species traits related to water use and photosynthesis partly explained differences in growth sensitivity to both long-term and short-term climate variations. Our study demonstrates that both climate means and anomalies shape tree growth in tropical forests, and that species traits can be leveraged to understand these demographic responses to climate change, offering a promising way forward to forecast tropical forest dynamics under different climate trajectories.

Bacterial biofilters usually exhibit a high microbial diversity and robustness, while fungal biofilters have been claimed to better withstand low moisture contents and pH values, and to be more efficient coping with hydrophobic volatile organic compounds (VOCs). However, there are only few systematic evaluations of both biofiltration technologies. The present study compared fungal and bacterial biofiltration for the treatment of a VOC mixture (propanal, methyl isobutyl ketone-MIBK, toluene and hexanol) under the same operating conditions. Overall, fungal biofiltration supported lower elimination capacities than its bacterial counterpart (27.7 ± 8.9 vs 40.2 ± 5.4 gCm(-3) reactor h(-1)), which exhibited a final pressure drop 60% higher than that of the bacterial biofilter due to mycelial growth. The VOC mineralization ratio was also higher in the bacterial bed (≈ 63% vs ≈ 43%). However, the substrate biodegradation preference order was similar for both biofilters (propanal>hexanol>MIBK>toluene) with propanal partially inhibiting the consumption of the rest of the VOCs. Both systems supported an excellent robustness versus 24h VOC starvation episodes. The implementation of a fungal/bacterial coupled system did not significantly improve the VOC removal performance compared to the individual biofilter performances.