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Increasing agricultural productivity is one of the most important aims of modern biotechnology. One way to enhance the productivity of crop species is to enhance the efficiency of photosynthesis. In C3 plants the oxygenase activity of Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo) limits the photosynthetic efficiency. The green microalgae Chlamydomonas reinhardtii has evolved a CO2 concentration mechanism (CCM) by increasing the CO2 concentration in the chloroplast stroma where RuBisCO is located. Four independent transgenic tobacco genotypes (LA, LB, C1 and C3) were generated producing the low CO2-inducible protein A and B (LCIA and LCIB) or the carbonic anhydrases I and III (CAH1 and CAH3) from C. reinhardtii CCM in the envelope, stroma, intermembrane space or thylakoid lumen of tobacco chloroplasts, respectively. All four recombinant proteins were active in planta, which had a substantial impact on carbon and nitrogen metabolism. Increasing the CO2 concentration near RuBisCO resulted in an enhanced rate of photosynthesis (by up to 15%), efficiency of photosystem II (by up to 18%) and chlorophyll content (by up to 19%). Although to differing extents, all four transgenic genotypes grew faster than wild-type plants, produced more shoot biomass (up to 45% more fresh weight or 38% more dry weight in the LA lines) and accumulated more photosynthetic end products, reflecting the higher rate of photosynthetic CO2 fixation. The proteome analysis revealed that the proteins changed in the transgenic genotypes compared to the wild-type plants were primarily associated with the regulation of the Calvin cycle and the amino acid biosynthesis. Metabolic analysis of the transgenic LA, LB and C3 plants revealed an increase in the levels of carbohydrates and also of most amino acids. Furthermore, transgenic LA and LB plants could maintain the enhanced biomass under low nitrogen conditions, where similarly-treated wild-type plants grew more slowly. The data generated in the present study confirmed that even single Chlamydomonas CCM components can be integrated into C3 plants to increase biomass, suggesting that transgenic lines combining multiple components or even a complete CCM could further increase the productivity and yield of C3 crops. RWTH Aachen University, Diss., 2017; Aachen, 1 Online-Ressource (151 Seiten) : Illustrationen, Diagramme(2017). = RWTH Aachen University, Diss., 2017 Published by Aachen

Ressourcen stellen die Basis für eine erfolgreiche industrielle und technologische Entwicklung dar und somit auch für den Wohlstand heutiger und zukünftiger Generationen. Mit steigender Ressourcennutzung nehmen auch die (physische und sozio-ökonomische) Verfügbarkeit abiotischer und biotischer Ressourcen, die Umweltverschmutzung und die sozialen Auswirkungen durch den Abbau und Nutzung der Ressourcen zu. Um den Erfolg implementierter Strategien (und deren Maßnahmen) hinsichtlich ihres Beitrags zu einem effizienten und nachhaltigen Umgang mit Ressourcen zu bewerten, bedarf es an entsprechenden Bewertungsmethoden. Diese Dissertation stellt vier Methoden bereit um die Bewertung abiotischer und biotischer Ressourcennutzung im Kontext der Nachhaltigkeit auf Produkt- und regionaler Ebene in konsistenter Weise zu bewerten. Die Methode zur Bewertung abiotischer Ressourcen auf Produktebene betrachtet insgesamt 21 relevante Aspekte und stellt Indikatoren zur Quantifizierung bereit. Für die Bewertung der sozio-ökonomischen Einschränkungen von Lieferketten ist eine neuer Ansatz entwickelt, der geopolitische, politische und regulative Aspekte berücksichtigt. Des Weiteren sind Screening-Indikatoren verfügbar, die die gesellschaftliche Akzeptanz der Ressourcennutzung adressieren. Um die Verfügbarkeit terrestrischer biotischer Ressourcen in Produktsystemen zu bewerten, wurde eine umfassende Methode mit 25 Indikatoren erstellt. Des Weiteren wird ein Ansatz vorgestellt, der es ermöglicht eine konsistente Zusammenführung und somit auch Bewertung verschiedener Ressourcentypen zu ermöglichen. Er findet bei der Zusammenführung der entwickelten Methoden zur Bewertung abiotischer und biotischer Ressourcen Anwendung. Da die Nutzung von Ressourcen auch auf Macro-Ebene betrachtet werden muss, wurde eine Methode zur Bewertung abiotischer Ressourcen auf regionaler Ebene entwickelt, die 25 Indikatoren für die Bewertung der Kritikalität (Verfügbarkeit von Ressourcen und Vulnerabilität der Region) und der gesellschaftlichen Akzeptanz zur Verfügung stellt. Verschiedene Fallstudien wurden durchgeführt um die Anwendbarkeit der entwickelten Methoden aufzuzeigen und zu verdeutlichen, warum eine umfassende Bewertung der Ressourcennutzung notwendig ist. Die Fallstudien umfassen u.a. die Bewertung eines Smartphones, Pkw-Herstellung und Biokraftstoffe. Die Anwendbarkeit der Methoden wird zudem erhöht, indem Indikatorwerte für 36 Metalle und 4 fossile Rohstoffe zur Verfügung gestellt werden. Die Bewertung der Nutzung abiotischer und biotischer Ressourcen auf Produkt- und regionaler Ebene wird mit dieser Dissertation signifikant verbessert, indem vier wissenschaftliche Methoden zur robusten und umfassenden Bewertung aller drei Nachhaltigkeitsdimensionen bereitgestellt werden. Resources are the basis for a thriving industrial and technological development and therefore for prosperity of present and future generations. With increasing resource use, challenges with regard to (physical and socio-economic) availability of abiotic and biotic resources and raw materials, pollution of the environment as well as social impacts associated with resource extraction and use arise. To evaluate the success of strategies managing resource use more efficiently and sustainably methodologies are required to comprehensively assess resource use and related impacts. This thesis provides four methodologies to improve the assessment of abiotic and biotic resource use in the context of sustainability on product and regional level. For the method to assess abiotic resources use on product level overall 21 aspects are considered as relevant and indicator for quantification are provided. In order to determine socio-economic supply chain restrictions a new approach is developed, considering geopolitical, political and regulatory aspects affecting resource extraction and use. Further, screening indicators are established to evaluate the societal acceptance of resources with regard to compliance with social and environmental standards. To assess the availability of terrestrial biotic resources in product systems a comprehensive methodology is established, which includes 25 indicators. Further, an approach is proposed to combine assessment methodologies in a consistent way. This approach is applied to the developed method of this thesis leading to a combined methodology. The use of resources also has to be considered on macro-economic. Thus, a methodology is developed providing 25 indicators for the two dimensions criticality, consisting of the sub-dimensions (physical and socio-economic) availability and vulnerability, as well as societal acceptance. Several case studies are carried out to demonstrate the applicability of the developed methods and to confirm the need for a comprehensive assess of resource use on micro and macro level, e.g. case studies for smart phones and cars, for biofuels produced from rapeseed and soybean. The applicability of the methodologies is further enhanced by providing indicator results for 36 metals and four fossil raw materials. The assessment of abiotic and biotic resource use on product and regional level is improved significantly by establishing four scientifically robust yet applicable methodologies, which consider multiple aspects of resource use in all three sustainability dimensions.

The IPCC stresses the importance of achieving net-zero CO2 emissions worldwide by 2050 and natural climate solutions, particularly carbon farming, can play a significant role in this goal. However, current markets do not account for environmental externalities, which creates a mismatch between individual costs and societal benefits. Payment systems linked to carbon farming practices could help bridge this gap. Research is essential to develop effective agricultural carbon markets, and this study focuses on the opportunities and challenges faced by smallholder farmers in these markets. The research examines four areas: agricultural markets as a funding source for carbon farming, payments for carbon sequestration, opportunities for smallholder farmers, and cost-effective monitoring and verification of carbon stocks. Further research is needed to monitor carbon sequestration accurately, reduce GHG emissions, and develop institutional arrangements to promote sustainable production methods in Africa.

Meeting the EU renewable fuel targets for 2020 will require a large increase in bioenergy feedstocks. To date, first generation biofuels have been the major response to meeting these targets. However, second generation biofuels from dedicated energy crops (e.g. miscanthus) or crop residues (e.g. straw) offer potential. Based on an on-farm survey of Farm Business Survey arable farmers in England and aggregated to national levels, we estimate that 5.27 Mt of cereal straw is produced annually on these farm types, of which farmers indicated that they would be willing to sell 2.5 Mt for bioenergy purposes, provided appropriate contractual conditions meet their needs. However, only 555Kt-840Kt would be obtained from straw currently incorporated into the soil. Timeliness of crop operations and benefits to soil were cited as key reasons for incorporating straw. A ‘good price’ represents the key incentive to encourage straw baling. With respect to dedicated energy crops, 81.6% (87.7%) would not consider growing miscanthus (SRC), while respectively, 17.2% (11.9%) would consider growing and 1.2% (0.4%) were currently growing these crops. Assuming 9.29% (average percentage of arable land set-aside between 1996-2005) of their utilised agricultural area to these crops, 89,900 ha (50,700 ha) of miscanthus (SRC) would be grown on English arable farms. Land quality issues, profitability and committing land for a long period of time were cited as both negative and positive reasons for farmer decisions about their level of willingness to grow these crops. Food and fuel policies must increasingly be integrated in order to meet societal goals without generating unintended consequences.

Agroecology is receiving increasing attention for its potential to reconcile environmental, sustainability and food production goals, through restoring the health of agricultural ecosystems and increasing the resilience of farms to future challenges. This study examined five different agroecological approaches that are currently practiced in Scotland to determine their potential to support the delivery of policy targets relating to climate change, biodiversity, and food production.

This paper first develops a partial equilibrium (PE) model to examine impacts of converting corn stover to biofuel on markets for corn and soybeans at the national market level. The PE model links gasoline, corn ethanol, dried distiller grains, corn, soybeans, and soybean meal markets in the presence and absence of a viable market for corn stover. The model also includes a technology which converts corn stover to bio-gasoline (a drop-in biofuel). The model evaluates profitability of the ethanol and bio-gasoline industries and assumes that these industries will expand/contract until profits reach zero. Given these assumptions and according to the predetermined supply and demand elasticities, the model determines equilibrium prices and their corresponding quantities for given exogenous variables defined in the model (such as crude oil price). The model is calibrated using data obtained for 2010 for USA economy and then solved for alternative crude oil prices in the presence and absence of a fixed subsidy of $1.01per gallon of bio-gasoline produced. Then we used the Purdue Crop Linear Programing (PCLP) model to assess farmers’ reactions to market equilibrium prices for corn, soybeans, and corn stover in the presence of a viable market for corn stover. The PCLP model determines profit-maximizing decisions for a given farm given its existing resources and estimated prices of commodities and input costs. We tuned the PCLP model according to the market clearing prices obtained from the PE model for a case when the crude oil price is $100 per barrel. Then using the tuned PCLP model we determined the optimum land allocation options for farmers. The partial equilibrium analyses show that: 1) with no bio-gasoline subsidy a limited amount of corn stover will be converted to biofuel even at very high crude oil prices; 2) The bio-gasoline subsidy could significantly boost production of this biofuel in particular at medium and higher crude oil prices; 3) no more than 45% of available corn stover will be removed for biofuel production; 4) converting corn stover to bio-gasoline boosts corn production, increases corn-corn rotation, and decreases supply of soybeans; and 5) converting corn stover to bio-gasoline changes the soybean to corn price ratio in favor of soybeans, at least in the very short term. The results obtained from the PCLP model show that the farm level land allocation decision is sensitive to the profitability of corn stover processing activities. When corn stover removal is introduced as a new option under the base case scenario at a corn stover price of $111 per ton) farmers allocate about 66% of their land to the corn-corn rotation and remove stover from their land. In this case corn stover is removed from 78.2% of available land at a rate of 1.18 tons per acre. If corn stover is demanded for biofuel production, then a major shift will be observed in crop rotations.

Permafrost-affected soils contain a huge reservoir of organic matter (OM) which, in the past, was largely persistent against microbial decomposition as consequence of cool and waterlogged conditions in the active layer, and freezing in the permafrost layer. Knowing the composition and degree of decomposition at molecular level of soil organic matter (SOM) is relevant to assess their vulnerability under impacts of climate change. This thesis investigated two major constituents of SOM, lignin and carbohydrates, across a west-east gradient in northern Siberia (longitudinal transect) and along a north-south gradient in western Siberia (latitudinal transect), aiming at identifying their fate once permafrost is thawing. The longitudinal transect included three continuous permafrost sites, from Cherskiy (CH) in north-eastern, Logata (LG) in north-central, and Tazovskiy (TZ) in north-western Siberia, which principally differ in active layer thickness and soil mineralogical properties. The latitudinal transect included all major biomes (tundra, taiga, forest steppe and steppe) from arctic to temperate ecosystems, which vary in mean annual temperature (MAT), mean annual precipitation (MAP), vegetation and soil properties. Lignin-derived phenols and neutral sugars within plant and soil samples at each horizon were analysed by CuO oxidation and trifluoroacetic acid (TFA) extraction methods respectively. Along the longitudinal transect, the stage of lignin degradation, appeared to increase from TZ to CH site. The stronger degradation of lignin and neutral sugars at TZ is supposed to be due to the higher MAT and larger active layer thickness, coinciding with better aeration and/or better mobilization of OM. In addition, the larger contents of Fe and Al (hydr)oxides likely additionally stabilized lignin-derived phenols associated with the mineral phase at these sites. With respect to the latitudinal transect, the stage of lignin degradation appeared to increase from tundra to forest steppe, then decrease to steppe. The increasing degree of lignin decomposition from tundra to forest steppe is likely due to decreasing soil moisture and increasing temperature which might favor the activity and assimilation of lignin-degarded microoragnisms, while drought and high pH are responsible for the restrained lignin decomposition in the steppe biome. The restrained lignin decomposition, in turn impairs the degradation of plant-derived carbohydrates because of a chemical linkage in form of lignocelluloses. It can be expected that increasing soil temperature and consequently increasing active layer thickness as the result of climate warming, which can cause two different soil hydrological scenarios, i.e., warm drier and warm wetter conditions will likely promote lignin and carbohydrate decomposition. This thesis thus contributes to a better understanding of the impact of permafrost thaw on OM stabilization in high latitude, and a magnitude in the realease of greenhouse gases into the atmosphere under global warming.

The energy expenditure (24h total energy expenditure, TEE) of a healthy individual or a patient is a vital reference point for nutritional therapy to maintain body mass. TEE is usually determined by measuring resting energy expenditure (REE) by indirect calorimetry or by estimation with the help of formulae like the formula of Harris and Benedict with an accuracy of ±20%. Further components of TEE (PAL, DIT) are estimated afterwards. TEE in intensive care patients is generally only 0–7% higher than REE, due to a low PAL and lower DIT. While diseases, like particularly sepsis, trauma and burns, cause a clinically relevant increase in REE between 40–80%, in many diseases, TEE is not markedly different from REE. A standard formula should not be used in critically ill patients, since energy expenditure changes depending on the course and the severity of disease. A clinical deterioration due to shock, severe sepsis or septic shock may lead to a drop of REE to a level only slightly (20%) above the normal REE of a healthy subject. Predominantly immobile patients should receive an energy intake between 1.0–1.2 times the determined REE, while immobile malnourished patients should receive a stepwise increased intake of 1.1–1.3 times the REE over a longer period. Critically ill patients in the acute stage of disease should be supplied equal or lower to the current TEE, energy intake should be increased stepwise up to 1.2 times (or up to 1.5 times in malnourished patients) thereafter. GMS German Medical Science; 7:Doc25; ISSN 1612-3174

Is locally produced food genuinely more sustainable? The motivation behind the “locavore” movement is usually thought to be the reduction of individual and institutional GHG emissions, but studies have shown that simply reducing food miles does not guarantee a more sustainable diet. Rachel Shindelar argues that despite this, choosing to participate in alternative local food systems instead of the conventional food system is a sure way to increase your access to environmentally friendly food and to support more ecologically sustainable agricultural practices: local food systems are as a whole more sustainable, both ecologically and socially.