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Neuartige Cellulosederivate werden ausgehend von kommerziellen Celluloseethern synthetisiert. Aufgrund der guten Löslichkeit der Celluloseether in polaren Lösungsmitteln erfolgt eine homogene Reaktionsführung, wodurch eine regelmäßige Verteilung der Sulfatgruppen entlang der Polymerkette gewährleistet wird. Durch Variation der Reaktionsparameter wie Sulfatierungsmittel, Lösungsmittel, Reaktionszeit und -temperatur erfolgte die Synthese zahlreicher Celluloseethersulfate mit unterschiedlichen Eigenschaften bezüglich Sulfatierungsgrad und kinematischer Viskosität. Durch Bestimmung des Schwefelgehaltes und entsprechender Berechnungen konnten die Anzahl der Sulfatgruppen im Molekül (DSSul) ermittelt werden, wobei die Werte für die synthetisierten Proben im Bereich zwischen DSSul = 0.1 bis DSSul = 2.7 lagen. Der Abbau der Polymerkette wurde ebenfalls durch die Reaktionsbedingungen gesteuert, sodass sowohl Produkte mit hohen (1698 mm2/s) als auch sehr niedrigen (2 mm2/s) kinemtischen Viskositäten resultierten. Wasserlöslichkeit der Produkte wurde durch Trübungsmessungen von 1%igen wässrige Lösungen und der daraus erhaltenen geringen Trübungswerte (NTU < 10) ermittelt. Die Funktionalisierung der Celluloseether mit Sulfatgruppen konnte mittels spektroskopischer Methoden nachgewiesen werden. In 13C-NMR-Spektren von Hydroxypropylcellulosesulfaten wurden zusammen-hängende strukturelle Veränderungen mit dem Anstieg des DSSul der Produkte korreliert. Durch charakteristische Signale im Bereich der Ether-Kohlenstoffatome und deren Verschiebung wurde belegt, dass die Sulfatierung des Celluloseethers an den freien Hydroxylgruppen der Etherseitenkette erfolgte. Mittels FT-RAMAN-Spektroskopie konnten für Sulfatgruppen charakteristische Banden der in den Spektren der sulfatierten Celluloseether nachgewiesen und zugeordnet werden. Aufgrund der ionischen Sulfatgruppen dissoziieren die Celluloseethersulfate in Wasser in geladene Polymerketten. Dadurch ist in Gegenwart von kationischen Polyelektrolyten (polyDADMAC) die Bildung von Polyelektrolytkomplexen in Form von Kapseln und Folien/Membranen möglich. Die Fähigkeit solcher Polyelektrolytkapseln aus Celluloseethersulat und polyDADMAC zu Verkapselung von Substanzen und deren anschließende Freisetzung wurde am Beispiel der Verkapselung des Fluoreszenzfarbstoffes Rhodamin B gezeigt. Mittels fluoreszenzspektroskopischer Messungen konnte der aus den Kapseln freiwerdende Farbstoff detektiert werden. Anhand der Messungen wurde gezeigt, dass die Farbstofffreigabe im Fall von Rhodamin B abhängig von den Probeneigenschaften ist. Durch die Wahl des Ausgangsstoffes und deren Funktionalisierung mit Sulfatgruppen kann die Farbstofffreisetzung gesteuert werden. Mit zunehmendem DSSul des Celluloseethersulfates verlängert sich die Verweilzeit des Fluoreszenz-farbstoffes in der Kapsel. Zusätzliche Funktionelle Gruppen in der Seitenkette des Ausgangsstoffes führen zu sterischen Hinderung bei der Wechselwirkung mit polyDADMAC, wodurch eine gegenseitige Durchdringung der Polymerketten bei der Ausbildung des Polyelektrolytkomplexes gehindert wird, sodass weniger kompakte Membranstrukturen der Kapseln resultieren. In Zellexperimente mit adhärenten Zelllinien an entsprechenden mit Celluloseethersulfat präpartierten Oberflächen wurde gezeigt, dass die Zelladhäsion durch den Sulfatierungsgrad der Proben beeinflusst wird. Auf Proben mit höherem Sulfatierungsgrad findet eine verbesserte Adhäsion im Vergleich zu Proben statt, die einen geringen Sulfatierungsgrad aufweisen. Demnach wird die Kompatibilität der Zellen auf solche Oberflächen durch die Erhöhung des Substitutionsgrades der Proben begünstigt.

Untersuchungen zu standortunabhängigen Eigenschaften des Wachstums für verschiedene Baumarten unter Verwendung einer Polynommethode und mit Hilfe des Evolonmodells.

Investments in planted forests in emerging markets are increasing and investors are looking for Sustainable and Responsible Investments (SRI) to integrate Environmental, Social And Governance (ESG) into the investment process. This study is presenting a first attempt to develop a framework to evaluate the ESG performance of investments in planted forests and to identify relations between the use of SRI tools and the financial performance of investments in planted forests. The analysis of 121 investments in planted forests allowed the identification of 339 organizations and 50 SRI tools (e.g.: management and investment standards, investment rating) operating with investments in planted forests in emerging markets. The analysis of the 50 SRI tools resulted in the definition of a ESG Reference Document including 155 issues. These issues were organized into an ESG Risk Assessment and have been tested in 12 case studies evenly distributed between Uganda, Cambodia and Vietnam. The results suggest that the most common instruments are management standards (e.g.: FSC), bank investment policies (e.g.: ABN AMRO Forest and Plantation Policy) and investment rating systems (e.g.: FairForest). The majority of the SRI tools have a broad sectoral approach and are managed by business organizations. Investors are using more than 30 SRI tools but these are characterized by a low level of control such as signature and/or participation or at the most a conformity declaration. On the contrary plantation companies are using less instruments but with top level of control such conformity assessment and certification. Aspects related to “Legal and Institutional framework” and “Environment” are the most represented inside SRI tools. On the contrary aspects such as “Minimum percentage of protected areas”, “Poverty reduction” and “Prevention of encroachment” are not only the less frequent issues but also the less controlled issues by SRI tools. The Gold Standard and the Forest Stewardship Council are the SRI tools with the highest performance among the 50 SRI tools analysed. The ESG Risk Assessment allows to identify the most important 25 issues and reveals that SRI tools are focusing on issues that on-the-ground are not the major risk sources. This is the case of “Third party certification” and “High Conservation Value Forests” (HCVFs). Few exemptions where SRI tools are properly identifying the major risks are “Tenure rights”, “Health and safety of workers” and “Social impact assessment”. Climate change impacts, long term financial sustainability, poverty reduction and encroachment are ranked as the most dangerous sources of risk across the 12 case studies. SRI tools are positively influencing the risk mitigation, accounting for a percentage of risk mitigation that ranges from 34.31 till 60.63%. FSC certification was often reported by projects’ stakeholders as a key instrument to mitigate risk of investments in planted forests.

The depletion of fossil fuels and the need to deal with climate change lead to an increasing interest in renewable resources. Lignocellulosic biomass in general, and agricultural residues in particular, could serve as an excellent starting material for the production of cellulose, basic chemicals, lignin and bioethanol in a biorefinery framework as they are abundant, do not compete with food production and are distributed worldwide. Two factors considerably influence the composition and properties of biorefinery products: biomass feedstock and pretreatment process. Their influence on the separability of raw material into a carbohydrate and lignin fraction as well as the composition and properties of these products are objectives of this study. Hereby, the focus is on lignin, as its structure is particularly dependent on the aforementioned factors complicating its further utilisation. Different agricultural biomass namely barley straw, coconut shell powder, hemp shives, horse manure, maize straw, miscanthus, oat husk, pretreated alfalfa, rape straw, sunflower stalks, tomato stalks and wheat straw were investigated regarding their suitability for lignocellulose separation using alkaline soda pulping. Best separation into a carbohydrate and lignin fraction was achieved for pretreated alfalfa, miscanthus, wheat and barley straw. The purity of the obtained lignin fractions varied in the wide range of 57% klason-lignin content for sunflower stalks and 81% for pretreated alfalfa prior to further purification by dialysis. Lignin fractions were characterised by means of FTIR spectroscopy, elementary analysis, thioacidolysis, size-exclusion-chromatography, thermodesorption, differential scanning calorimetry and different wet chemical methods for determination of functional groups. Lignins could be classified into groups, within which they show similar characteristics: (A) horse manure, rape straw, (B) sunflower stalks, tomato stalks, (C) barley-, maize- and wheat straw and (D) hemp shives, miscanthus. In addition, promising lignin candidates were found for several applications. Thus, by screening different agricultural residues, it is possible to choose a specific raw material, in order to produce lignin with desired properties and functionalities. The effect of the pretreatment process was studied based on wheat straw. It was subjected to conventional alkaline pulping, microwave-assisted alkaline pulping and organosolv pulping using formic acid and hydrogen peroxide. Pulping parameters were varied in order to attain best possible separation into a carbohydrate and lignin fraction. Of the varied parameters the concentration of both sodium hydroxide and formic acid has the highest impact on yield and purity of the products for alkaline and organosolv pulping, respectively. It additionally influences the content of functional groups of the lignin fraction and is hence, an important parameter for lignin customisation for subsequent utilisation. Furthermore, the possibility of reducing pulping time by using microwave-assisted pulping instead of conventional alkaline pulping is promising, as the obtained carbohydrate fraction has a low intrinsic viscosity, which may enhance enzymatic hydrolysis.

Climate change is one of the major contributing factors to degradation of ecological services, and these in turn are harming many people and causing poverty mainly in rural areas. The information available and the gain of knowledge on how climate change is affecting livelihood resources in the Bolivian Andes are very limited. This research aims to advance in the understanding of adaptive capacity to social and climate change in rural communities whose livelihoods are dependent upon agriculture and local resources. The proposed framework of this research focuses on the vulnerability assessment of the socio-ecological system, which targets on the identification of adaptation strategies in the context of their contribution to the overall adaptive capacity of the system. Following an exploratory design, two representative communities from different agro-ecological regions are selected as case studies: Santiago de Okola (Municipality of Puerto Carabuco, highlands) and Sita-Chorocana (Municipality of Inquisivy, inter-Andean valley). The research is conducted using a participatory rural appraisal approach and combines indicators encompassing natural, physical, human, financial, and socio-cultural variables. Data collection is based on community discussion (n=6), key informant interviews (n=31), household interviews (n=125), and local observations. Data analysis is conducted for quantitative and qualitative information. The results are presented in four main sections: 1) Integral diagnosis of the current situation in each case study considering general characteristics of the population, agriculture activities and forest resources; followed by a complete description of impacts and strategies to cope with extreme weather events and socio-economic conflicts at household level. 2) The assessment of strategies based on cultural knowledge describes the existing traditional ecological knowledge and local customs. Moreover, a mathematical model has been developed to evaluate the current knowledge needed to cope with and adapt to climate change. The outcomes point out that for the highlands the diversification of knowledge, and for the inter-Andean valley the social—pooling are strategies that contributed the most to secure crop production under extreme weather event scenario. 3) The assessment of socio-economic strategies identifies households under the category of poor as the most vulnerable group to climate change; this group is dominated by old women living alone in the communities and in charge of the farm. Based on the redundancy analysis poverty indicators have been identified: In the highlands, off-farm activities represent a potential strategy whenever the crop production is reduced or limited; these activities are related to the labor availability in the household, health conditions and level of education. In the inter-Andean valley, out-farm and eucalyptus plantations represent a potential strategy to secure crop production when households have access to land and markets and they participate in social networks. 4) The assessment of social networks identifies the relationship between the households, stakeholders, and the municipality to cope with socio-economic conflicts and the impacts of extreme weather events. Independently of each case study, the outcomes point out the existing social networks under socio-economic scenario contributed to the implementation of a wide number of coping strategies to secure in the long-term the well-being of the household including economic development, food production, education, social organization, infrastructure, and health. The existing social networks under the extreme weather events scenarios contributed mainly to secure food production of the households by providing immediate access to labor. This research presents evidence on how social and climate changes are the major contributing factors to increasing vulnerability of the socio-ecological system. It is the first explorative research in which cultural knowledge, socio-economic and social networks strategies are integrated to understand the adaptive capacity of rural communities in the selected case studies. The livelihood adaptation strategies identified independently of each of the two case study eco-regions showed particular characteristics related to the lifestyle, the knowledge and the socio-economic resources available in the communities; and highlights the potentialities and limitations of the households to reduce their vulnerability. Finally, the proposed model towards adaptive capacity is a tool that can be used to guide new policies and programs that target poverty reduction and minimize the adverse impacts of climate change.

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The macrophytes have the ability accumulating multiple metals/metalloids species from the terrestrial and aquatic environments. The environmental-friendly phytoremediation technologies via these plant species have been applied for non-degradable pollutants removal. The macrophytes derived rhizofiltration is a major and efficient technology for metals/metalloids removal, especially in aquatic environments (e.g. wetland). Comparing with the common metals/metalloids often studied, aquatic U rhizofiltration via macrophytes has been just considered recently. In this study, the field investigation in a U tailing basin wetland showed that the rhizofiltration was crucial for aquatic U retention via Phragmites australis Trin ex Steud. (water to root bioconcentration factor (BCF): 670 to 1556). The aquatic U retention efficiency in aboveground biomass of P. australis was insufficient (BCF: 0.4 to 5.3), comparing with the rhizofiltration. However, the high productivity (1.2 to 1.9 kg•m-2 per growing season) of P. australis still resulted in a notable yearly U accumulation in the areal total aboveground biomass (0.04 to 0.35 mg•m-2 per growing season). It was potentially promoted by the enhanced aquatic U rhizofiltration. The U within aboveground biomass could be released to submerse soil with the degradable or recalcitrant fallen litters. It enhanced the organic carbon supply in rhizosphere together with the root litter, and potential water to root U translocation within mobilized organic compounds. Hence the rhizofiltration stood in the crucial position of the plant-litter-water-soil U recycling in aquatic environment. The results from field investigation and mesocosm experiment further suggested that the Fe plaque (IP) on root surface was crucial for aquatic U rhizofiltration. The IP contained most of root retained U in both environments (proportion of U within IP: 55.8 to 82.6% in field and 66.7 to 86.0% in mesocosm). However, the efficiency of IP assisted aquatic U rhizofiltration was affected by the redox state gradient (-179 to 220 mV) related redox processes. Field investigation suggested that high content of dissolved oxygen (up to 8.2 mg•l-1) was capable to rapidly oxidize soluble Fe(II) as sparingly soluble Fe(III) oxides precipitated in subhydric soil. It consequently limited the aquatic Fe availability for root uptake and precipitation as IP. However, the strong oxidation ability also relatively increased aquatic U(VI) availability incorporated with inorganics and degradable organic matters. It was adverse for controlling the aquatic U concentration (66.7 to 92.0 μg•l-1 in field). On the other hand, it also benefited the U uptake by inner root tissue and upward translocation to aboveground biomass of P. australis. The different inorganic N species also significantly influenced IP assisted aquatic U rhizofiltration. The aquatic NH4+ sustained the reduction and acidification (via nitirification) potential for Fe(III) and U(VI) bioreduction in rhizosphere (-87 to 21 mV in NH4+ cultured mesocosm pots). It improved the root uptake (mainly within IP) of Fe and U (2992.9 to 5010.7 mg•kg-1 Fe and 45.7 to 62.8 mg•kg-1 U in NH4+ cultured root). On the contrary, the NO3- depended strong oxidation ability (23 to 224 mV in NO3- cultured mesocosm pots) inhibited the IP formation and the related aquatic U rhizofiltration efficiency (1568.5 to 2569.5 mg•kg-1 Fe and 26.2 to 49.6 mg•kg-1 U in NO3- cultured root). The aquatic U availability in rhizosphere was also increased via NO3- depended oxidation processes (aquatic U concentration in mesocosm: 1.6 to 589.3 μg•L-1 (NO3-) vs. 1.4 to 58.2 μg•L-1 (NH4+)). The sufficient nitrogen supply is also a significant driving force for high biomass productivity of P. australis. The higher biomass of P. australis increased the U accumulation capacity for root and aboveground tissues. The nitrogen related high biomass accumulation of P. australis also potentially enhanced the share of organic bound U in subhydric soil via plant litters supply. The IP assisted aquatic U rhizofiltration was also affected by the co-existing metals/metalloids in rhizosphere. The field investigation indicated that high As availability (aquatic As/U ratio: 0.7 to 1.6) inhibited the U retention within IP through the competitive absorption, due to its high affinity to IP. The Ca improved the aquatic U(VI) availability by forming the soluble Ca-uranyl-carbonate compounds. The Ca also potentially competed with hydrated Fe(III) oxides within IP by incorporating with U and encourage the U retention within inner root tissue. The P was beneficial for U retention within IP possibly in form of U-Fe-phosphate complexes. However, it was still need to be proofed in further studies. Despite of the biogeochemical conditions in rhizosphere, the aboveground transpiration of P. australis also affected the IP formation and related aquatic U rhizofiltration. The higher transpiration rate (TR) of P. australis (3.3±1.2 mm•d-1 in field, 4.5±2.0 mm•d-1 (NH4+)/5.0±2.2 mm•d-1(NO3-) in mesocosm) increased the aquatic nutrient/non-essential elements availability for root uptake. For this reason, the aquatic U rhizofiltration of P. australis (21.8±3.1 mg•kg-1 in field, 62.1±1.0 mg•kg-1 (NH4+)/47.6±1.8 mg•kg-1 (NO3-) in mesocosm) was enhanced under higher TR. The higher TR also promoted the formation of IP and its U retention capacity. Furthermore, the U translocation from root to above ground biomass (mainly in leaves) of P. australis was also enhanced under higher TR. It was potentially benefited by the increased transpirational pull and root uptake of other active mediator (e.g. Ca). The effect of transpiration was also coupled with the different N species on IP assisted aquatic U rhizofiltration. The higher TR depended strong root uptake and assimilation of N increased the biomass accumulation of P. australis. Furthermore, the higher TR also potentially increased the share of root in biomass partition of P. australis. Consequently, the stronger transpiration resulted in the higher aquatic U accumulation in area related root biomass (up to 84.0±3.6 mg•m-2 (NH4+) and 86.4±5.8 mg•m-2 (NO3-) U per season in mesocosm). In conclusion, it was possible for eutrophic P. australis stands to retain the aquatic U via rhizofiltration. The IP on root surface was a crucial mediator contributing the aquatic U rhizofiltration, especially in iron rich milieu. The efficiency of IP assisted aquatic U rhizofiltration could be further improved under suitable environmental conditions. In this study, these conditions might include: i) reductive rhizosphere environment with active reducers (e.g. NH4+) encouraging Fe(II) generation for IP formation and U retention within it; ii) limited competitive elements (e.g. As and Ca) co-existed with Fe and U in rhizosphere; iii) sufficient nutrients (e.g. N) supply and related high biomass productivity of plant; iv) strong transpiration effect improved the nutrient assimilation of root and also the aquatic U/Fe availability for root uptake. By adjusting these conditions (also include other potential factors not discussed in this study), an effective rhizofiltration technology was supposed to be applied for aquatic U removal.