Fotosyntese og vekst ved høye CO2 konsentrasjoner og ulike dag temperaturer

Increasing energy prices have led to the attempt of energy saving and are one of the main research areas in greenhouse plant production. Technical disintegration has been developed, and the greenhouse concept ‘Closed/Semi-Closed Greenhouse’ was introduced. The idea of this concept is to reduce energy consumption by cooling the greenhouse under high light intensities, and storing the heat in an underground aquifer to be regained for heating. In order to improve the efficiency of the concept the main focus of this work is investigating how high day temperatures the plants can tolerate at high CO2 levels without a reduction in photosynthesis or growth. The average 24 hour temperature is the most important number for the development rate of plants. When day temperatures are high it is therefore desirable to lower the night temperatures. Plants that tolerate high day/low night temperatures will reduce the energy input for cooling in ‘Closed/Semi-Closed’ greenhouses during the day, and will reduce heating demand during the night. In this study we used different maximum day temperatures, low and moderate night temperatures, high and ambient CO2 levels, and manipulation of light quality because high day/low night temperatures lead to shoot elongation. Eight species of herbs, basil (Ocimum basilicum), rocket (Eruca vesicaria), thyme (Thymus vulgaris), oregano (Origanum vulgare), lemon balm (Melissa officinalis), cilantro (Coriandrun sativum), sage (Salvia officinalis) and rosemary (Rosmarin officinalis) were used for investigating the effect of high day temperature on biomass production and morphology. The tomato varieties (Solanum lycopersicum “Mecano”, “Capricia”, “Cederico”) were used to investigate plant response on growth, pollination and fruit development under high day temperatures. The plants were grown in phytotron growth rooms, common greenhouse growth rooms, and gas exchange chambers. When testing the increase of red/far-red light ratio on the elongation of herbs, the plants were covered with a colored plastic film. The first two investigations were performed by increasing the maximum day temperature stepwise with increasing light intensity while keeping night temperatures steady. The third and fourth investigations were performed using natural increase of maximum day temperature from increasing light intensities, and different but steady night temperatures. The herbs responded positive to increased maximum day temperatures from 22°C to 29°C with increased dry matter production. An increase of the red/far-red ratio from 1.1 to 10.2 reduced the elongation growth, but also reduced dry matter production due to the 34% lower light intensity below the plastic film. Increasing the maximum day temperature from 23°C to 29°C under high CO2 conditions and constant night temperatures did not affect total dry matter production of the tomato plants, but reduced the yield when the maximum day temperature was higher than 23°C, due to a reduction in fruit number and size. Above 23°C maximum day temperature and constant night temperatures a high number of un-pollinated fruits developed. At constant mean day temperature, flowers developed under the highest day and lowest night temperatures (30/11 °C) showed the highest number of pollen and best germination. However, fruits developed under lower day and higher night temperatures (24/17 °C) had a higher amount of soluble solids, dry matter and titratable acid. The carbon exchange rate (CER) of single tomato plants increased under high CO2 concentrations with increasing light up to a temperature of 40-45°C. The CER was about 100% higher for plants grown under high CO2 conditions compared to plants grown under ambient conditions. Chlorophyll fluorescence measurements showed no effect of high maximum day temperatures on the activity of photosystem II. Night temperatures down to 10-11°C showed no negative effect on the CER during the following days and the dark respiration. The results achieved in this study show that under high CO2 concentration and high light intensities, the maximum day temperature can be increased and low night temperatures can be accepted without any negative effects on photosynthesis and plant growth. These results can be used in the future to develop strategies with controlled maximum day temperatures in relation to lower night temperatures and combined with CO2 strategies. They will have great potential for energy saving especially connected to the ‘Closed/Semi-Closed’ greenhouse concept.Økende energipriser har ført til at veksthusnæringen er meget bevist på å redusere energiforbruket og at energieffektivisering har blitt et sentralt forskningsområde. Tekniske løsninger har blitt utviklet og et nytt dyrkingssystem kalt «lukkede/delvis lukkede veksthus» blitt introdusert. Dette dyrkingssystemet har som mål å redusere energiforbruket ved blant annet å kjøle veksthuset ved sterk innstråling og lagre denne energien for så å bruke den til oppvarming ved behov. For å bedre energieffektiviteten ved dette dyrkingssystemet har en i dette arbeidet undersøkt hvor høye temperaturer plantene kan tolerere ved høy CO2 uten reduksjon i fotosyntese eller vekst. Det er den gjennomsnittlige døgntemperaturen som hovedsakelig bestemmer utviklingshastigheten hos planter. Ved høye dagtemperaturer er det derfor ønskelig å senke natt temperaturen. For planter som tolererer høye dagtemperaturer/lave natt temperaturer vil det være et mindre krav til kjøling om dagen ved høy innstråling og redusert behov for oppvarming om natta ved bruk av lukkede/delvis lukkede veksthus. I dette arbeideidet ble brukt høye dagtemperatuerer, natt temperaturer, ulike CO2 nivåer og regulering av lyskvaliteten da en kjenner til at høye dag/lave natt temperaturer gir strekningsvekst hos planter. Det ble brukt åtte ulike arter av urter: basilikum (Ocimum basilicum), ruccola (Eruca vesicaria), timian (Thymus vulgaris), oregano (Origanum vulgare), sitronmelisse (Melissa officinalis), koriander (Coriandrun sativum), salvie (Salvia officinalis) and rosmarin (Rosmarin officinalis) for å undersøke virkningen på vekst og morfologi. Videre ble brukt tomat (Solanum lycopersicum “Mecano”, “Capricia”, “Cederico») for å undersøke virkningen på vekst, pollinering og fruktkvalitet ved høye dagtemperaturer. Plantene ble dyrket i dagslysrom i fytotron, vekshusavdelinger eller gassutvekslingskammere. For å teste rød/mørkerødt forholdet på strekningsvekst hos planter ble brukt en farget plastikk. De to første arbeidene ble utført ved en gradvis økning av den maksimale dagtemperaturen ved økende belysningsstyrke og med faste natt temperaturer. De to siste arbeidene ble utført ved at dagtemperaturen økte naturlig ved økende belysningsstyrke og ved forskjellige natt temperaturer. Hos urter økte veksten ved å øke den maksimale dagtemperaturen fra 22 °C til 29 °C, mens en i kommersiell dyrking bruker en betydelig lavere temperatur, 13-18 °C. Ved å øke rød/mørkerødt forholdet fra 1,1 til 10,2 ble strekningsveksten redusert, men det førte også til en redusert vekst da plastikken som ble brukt førte til en lysreduksjon på 34 %. Ved å øke den maksimale dagtemperaturen fra 23 °C til 29 °C ved høy CO2 og konstant natt temperatur ble det ingen virkning på tørrstoffproduksjonen hos tomatplantene, men en redusert avling ved maksimale dag temperaturer over 23 °C, som skyltes redusert antall og størrelse på fruktene. Maksimale dagtemperaturer over 23 °C og konstant natt temperatur, førte til et økende antall ikke pollinerte tomater. Ved konstant gjennomsnitts temperatur, utviklet tomatblomsterne ved høy dag og lav natt temperatur (30/11 °C) det største antall pollen og med best spireevne. Mens tomater utviklet under midlere dag/natt temperatur (24/11 °C) hadde høyest mengde oppløst tørrstoff, høyest tørrstoffinnhold og høyest titrerbar syre. Måling av CO2 opptaket (CER) hos enkeltplanter av tomat ved høye CO2 nivåer viste at ved økende belysningsstyrke økte fotosyntesen helt opp til 40-45 °C. CO2-opptaket var dobbelt så høyt for planter dyrket ved høyt CO2 som ved normalt CO2 nivå ved disse betingelsene. Målinger av klorofyll fluorescens viste ingen virkning på fotosystem II ved høye dag temperaturer. Natt temperaturer ned til 10-11 °C viste ingen negativ virkning på CO2 opptaket eller mørke respirasjonen. Resultatene i dette arbeidet viser at dag temperaturen kan økes betydelig under gode lysforhold og høye CO2 nivåer. Resultatene viser også at natt temperaturen kan senkes uten at fotosyntesen eller veksten reduseres for tomat. I fremtiden bør disse resultatene kunne brukes for utvikling av strategier for å øke dagtemperaturen ved økende belysningsstyrke og høy CO2, samtidig som natt temperaturen kan senkes. Dette vil kunne føre til en betydelig energisparing ved bruk av lukkede/delvis lukkede veksthus

Die Veränderung der Oxygenierung chirurgischer Intensivpatienten: frühes Leitsymptom der schweren Sepsis

Bei der Untersuchung der schweren Verlaufsform einer Sepsis wurde unter der speziellen Fragestellung einer früheren Diagnosestellung die Verschlechterung der Oxygenierung als frühestes Merkmal identifiziert.Aus dieser Beobachtung ergab sich die Frage nach der Häufigkeit des frühen Auftretens dieses Symptoms im Vergleich zu anderen Sepsisparametern. Es stellte sich des Weiteren die Frage nach signifikanten Unterschieden bei den überlebenden und versterbenden Patienten. Es erfolgte die retrospektive Analyse von 33 Fällen einer schweren Sepsis unter besonderer Berücksichtigung der Oxygenierung im zeitlichen Verlauf. Zur Prüfung der Unterschiede der untersuchten Variablen zwischen überlebenden und versterbenden Patienten wurde der U-Test nach Mann und Whitney eingesetzt. Darüber hinaus wurde eine Diskriminanzanalyse durchgeführt. Bei allen Patienten war eine verschlechterte Oxygenierung frühes Symptom der Sepsis. In mehr als ¾ der Fälle trat dieses Leitsymptom früher auf als alle anderen Organdysfunktionen. In 79% der Fälle konnte die Oxygenierungsverschlechterung früher als eine PCT-Erhöhung > 2 ng/ml festgestellt werden. Signifikante Unterschiede zwischen überlebenden und versterbenden Patienten zeigten sich im Alter und in der Zeit zwischen dem Auftreten der Oxygenierungsverschlechterung und dem Beginn der wirksamen antibiotischen Therapie. Bei der Diskriminanzanalyse werden diese Ergebnisse bestätigt. Die akute Verschlechterung der pulmonalen Funktion erfordert aufgrund der erheblichen therapeutischen Konsequenzen eine umgehende Differentialdiagnostik. Dass die Verschlechterung der Oxygenierung einziges Frühsymptom einer schweren Sepsis sein kann, wird mit dieser Untersuchung gezeigt und muss somit in die Differentialdiagnostik einbezogen werden

Environmental and social life cycle assessment of growing media for urban rooftop farming

Acord transformatiu CRUE-CSICUnidad de excelencia María de Maeztu CEX2019-000940-MPurpose: New environmental strategies are emerging for cities to become more self-sufficient, such as hydroponic crop production. The implementation of such systems requires materials that usually originate in countries with low labour costs and other legal regulations. To what extent could these strategies be shifting problems across the globe? To answer this question, we performed a comprehensive environmental and social assessment of the various extended soilless systems used to grow vegetables on urban roofs. Methods: Three different growing media constituents were chosen for this study: perlite, peat and coir; which are produced in three countries, Turkey, Germany and the Philippines, respectively, and are imported to Spain. By using a life cycle assessment, we evaluated the environmental performances of the production and transport of these growing media. Additionally, we performed a social life cycle assessment at different levels. First, we used the Social Hotspots Database to analyse the constituents in aggregated sectors. Second, we performed a social assessment at the country and sector levels, and finally, we evaluated primary company data for the social assessment of the constituents through questionnaires given to businesses. Results and discussion: The coir-based growing medium exerted the lowest environmental burden in 5 out of 8 impact categories because it is a by-product from coconut trees. In contrast, perlite obtained the highest environmental impacts, with impacts 44 to 99.9% higher than those of peat and coir, except in the land use. Perlite is a material extracted from open-pit mines that requires high energy consumption and a long road trip. Regarding the social assessment, peat demonstrated the best performance on all the social assessment levels. In contrast, coir showed the worst scores in the Social Hotspots Database and for the impact categories of community infrastructure and human rights, whereas perlite displayed the lowest performance in health and safety. Nevertheless, coir and perlite evidenced much better scores than peat in the impact subcategory of the contribution to economic development. Conclusions: This study contributes to a first comparison of three imported growing media constituents for urban rooftop farming from environmental and social perspectives to choose the most suitable option. Peat appears to be the best alternative from a social perspective. However, from an environmental standpoint, peat represents a growing medium whose availability is aiming to disappear in Germany to preserve peatlands. Therefore, we identify a new market niche for the development of local growing media for future rooftop farming in cities

Trophic position and foraging ecology of Ross, Weddell, and crabeater seals revealed by compound-specific isotope analysis

Ross seals Ommatophoca rossii are one of the least studied marine mammals, with little known about their foraging ecology. Research to date using bulk stable isotope analysis suggests that Ross seals have a trophic position intermediate between that of Weddell Leptonychotes weddellii and crabeater Lobodon carcinophaga seals. However, consumer bulk stable isotope values not only reflect trophic dynamics, but also variations in baseline isotope values, which can be substantial. We used compound-specific isotope analysis of amino acids (CSI-AA) to separate isotopic effects of a shifting baseline versus trophic structure on the foraging ecology of these ecologically important Antarctic pinnipeds. We found that Ross seals forage in an open ocean food web, while crabeater and Weddell seals forage within similar food webs closer to shore. However, isotopic evidence suggests that crabeater seals are likely following sea ice, while Weddell seals target productive areas of the continental shelf of West Antarctica. Our CSI-AA data indicate that Ross seals have a high trophic position equivalent to that of Weddell seals, contrary to prior conclusions from nitrogen isotope results on bulk tissues. CSI-AA indicates that crabeater seals are at a trophic position lower than that of Ross and Weddell seals, consistent with a krill-dominated diet. Our results redefine the view of the trophic dynamics and foraging ecology of the Ross seal, and also highlight the importance of quantifying baseline isotope variations in foraging studies

Seasonal Habitat Preference and Foraging Behaviour of Post-Moult Weddell Seals in the Western Ross Sea

Weddell seals (Leptonychotes weddellii) are important predators in the Southern Ocean and are among the best-studied pinnipeds on Earth, yet much still needs to be learned about their year-round movements and foraging behaviour. Using biologgers, we tagged 62 post-moult Weddell seals in McMurdo Sound and vicinity between 2010 and 2012. Generalized additive mixed models were used to (i) explain and predict the probability of seal presence and foraging behaviour from eight environmental variables, and (ii) examine foraging behaviour in relation to dive metrics. Foraging probability was highest in winter and lowest in summer, and foraging occurred mostly in the water column or just above the bottom; across all seasons, seals preferentially exploited the shallow banks and deeper troughs of the Ross Sea, the latter providing a pathway for Circumpolar Deep Water to flow onto the shelf. In addition, the probability of Weddell seal occurrence and foraging increased with increasing bathymetric slope and where water depth was typically less than 600 m. Although the probability of occurrence was higher closer to the shelf break, foraging was higher in areas closer to shore and over banks. This study highlights the importance of overwinter foraging for recouping body mass lost during the previous summer

Regional variability in diving physiology and behavior in a widely distributed air-breathing marine predator, the South American sea lion (Otaria byronia)

Our understanding of how air-breathing marine predators cope with environmental variability is limited by our inadequate knowledge of their ecological and physiological parameters. Because of their wide distribution along both coasts of the sub-continent, South American sea lions (Otaria byronia) provide a valuable opportunity to study the behavioral and physiological plasticity of a marine predator in different environments.We measured the oxygen stores and diving behavior of South American sea lions throughout most of its range, allowing us to demonstrate that diving ability and behavior vary across its range.We found no significant differences in mass-specific blood volumes of sea lions among field sites and a negative relationship between massspecific oxygen storage and size, which suggests that exposure to different habitats and geographical locations better explains oxygen storage capacities and diving capability in South American sea lions than body size alone. The largest animals in our study (individuals from Uruguay) were the shallowest and shortest duration divers, and had the lowest mass-specific total body oxygen stores, while the deepest and longest duration divers (individuals from southern Chile) had significantly larger mass-specific oxygen stores, despite being much smaller animals. Our study suggests that the physiology of airbreathing diving predators is not fixed, but that it can be adjusted, to a certain extent, depending on the ecological setting and or habitat. These adjustments can be thought of as a 'training effect': as the animal continues to push its physiological capacity through greater hypoxic exposure, its breath-holding capacity increases