This thesis presents an assessment of farmers' behaviour in response to current changes in climate and policy in the UK. At present, many catchments in England are considered as over licensed or over abstracted and although water licence trading is regarded as a potential solution to the problem, and is currently possible, high transaction costs and institutional barriers deter farmers from trading. In response, two new water allocation systems have been proposed to provide farmers with the ability to adapt to climate and demand change pressures (i.e. basic and enhanced systems). A review of the current literature suggested farmers' behaviour very much influences the success of policy interventions. Therefore, this study sought to understand the behavioural intentions of farmers in England, and the underlying factors which drive their decision-making, under different climate and policy scenarios. Furthermore, this study examined whether farmers with different behavioural intentions lead to different patterns of abstraction behaviour at the system level, thus providing a means of assessing the current and proposed water allocation systems. An empirical survey was conducted within the Great Ouse catchment in eastern England, UK, where freshwater availability for crop irrigation is considered highly vulnerable to climate change. The questionnaire, and subsequent interpretation of behaviours, was developed under the theoretical framework of the Theory of Planned Behaviour (TPB) (Ajzen, 1991). Farmers' preferred behavioural intentions were identified under different strategic (long-term) and in-season (short-term) water shortage and surplus scenarios. Furthermore, the TPB explained between 29-65 % of the variance in intention, based on Nagelkerke's R2, and was similar to the range found by meta-analytical reviews (i.e. 40-49 % based on R2). In addition, attitude and subjective norm were found to be significant predictors of intention in three of the four scenarios. Overall, farmers believed they have greater volitional control with regards to decision-making in the long-term but less in the short-term. Furthermore, a behavioural farm typology based on farmers' preferred behavioural intentions was used in the development of an Agent-Based Model (ABM) to simulate system level patterns of abstraction behaviour which emerge from individual farm level decision-making. The scenario simulation results indicated the proposed enhanced water allocation system was likely to provide the greatest utility to balance the needs of licence users, at least farmers, whilst protecting the environment.

Rapid urbanization in the developing world is one of the greatest challenges of the 21st century. Rates of urban poverty and food insecurity are increasing: whereas agricultural and urban water demand is exceeding supply leading to scarcity in many regions. Meanwhile, the speed of urban growth is outpacing the provision of water and sanitation infrastructure. This fact requires innovative interventions that could mitigate the negative impacts of urbanization. Urban agriculture is presented as one significant measure to increase the food self-reliance and improve the livelihood of urban inhabitants, patiicularly poor. Given that freshwater provision in cities of most developing countries is already below standard, covering the water requirements for urban agriculture has been extremely difficult. Greywater is seen as a good option for urban agriculture. Greywater is less polluted than blackwater, thereby; treatment of greywater to make it suitable for local-food production tends to be safer, easier and less controversial. This study developed and tested a new treatment method for grey water called the Drawer Compacted Sand Filter (DCSF). This is a modified sand filter design in which the sand filter is broken down into several layers approximately 10 cm high, each of which is placed in a movable drawer that is stacked veliically, with each drawer separated by 10 cm of space. This treatment unit is seeking to overcome the problems commonly found in traditional sand filter designs, such as clogging, emission of bad odours and need for a large land area to house the filter. The new design was proposed and developed to be suitable in urban communities and could produce good quality water that matches the requirements of food production in urban areas. The response of drawer sand filters to variable hydraulic and organic loading rates in terms of Biological Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total suspended Solid (TSS), pH, Electrical Conductivity (EC) and Escherichia coli (E.coli) reductions was tested in laboratory under controlled conditions. Hydraulic Loading Rate (HLR) was studied by increasing it stepwise from 72 to 142 L m-2 day-l and Organic Loading Rate (OLR) was studied by increasing it fi'om 24 to 30 g BOD5 m-2 dail while keeping the HLR constant at 142 L m-2 day-I. Each loading regime was applied for 110 days. Results showed that DCSF was able to remove > 90% of organic matter and Total Suspended Solids for all doses. No significant difference was noticed in terms of overall filter efficiency between different loads for all parameters. Significant reduction in BOD5 and COD (P<0.05) was noticed after water drained through the third drawer in all tested loads. Based on the laboratory tests, nine pilot DCSF units were operated at different locations in Jordan during the period of 2011-2013. Composite water samples from the inlet and outlets of the DCSF over a period of 16 months were taken periodically and tested for BOD5, COD, TSS, pH, EC and E.coli. A socio-economic study was conducted to evaluate the validity and feasibility of the DCSF. The results showed that DCSF removed 78-96% ofBOD5 and COD and 98% of TSS and up to 6 logs reduction in E.coli. The socio-economic study and the costbenefit analysis showed that DCSF unit was a feasible and reliable treatment method for greywater with a very low land footprint and minimal maintenance requirements, thus making it suitable for a wide range of geographical settings. ii

In horticultural sectors where water is a threatened resource, altering irrigation frequency may present a viable approach to reduce water use, without any negative effect on crop yield and/or quality. However, our understanding of the physiological impact of this approach in containers in a peat based substrate is limited. Pelargonium x hortorum Bullseye plants were grown in glasshouse conditions under well-watered (WW; daily replacement of 100% of evapotranspiration (ET)), frequent (FDI), or infrequent (IDI) deficit irrigation regimes (50% of ET supplied daily or cumulatively every 4 days, respectively) for four weeks. Both FDI and IDI resulted in short-term increases in water use efficiency, and longer term increases in plant quality (canopy compactness) compared to WW plants. From a physiological perspective, stomatal conductance (gs) decreased similarly under both FDI and IDI, but there were treatment differences in leaf water potential (Ψleaf). FDI resulted in a more positive Ψleaf compared to WW plants, whilst Ψleaf under IDI was typically the lowest. Given the lack of a consistent response for Ψleaf, this suggested another mechanism was regulating stomata in P.hortorum. Under a single drying cycle, different components of the xylem sap were measured. Xylem sap pH, Ca2+ and NO3 - did not change, but the plant hormone abscisic acid (ABA) increased in the xylem sap ([X-ABA]leaf) under both irrigation treatments as soil moisture decreased, and showed a strong relationship with gs both in vivo and in a detached leaf transpiration bioassay. However, when plants were irrigated daily at a percentage of daily ET (adapted from FDI), plants showed an attenuated ABA response compared to when irrigation was withheld (adapted from IDI). It was hypothesised that this may have been a root-derived response due to spatial variation in soil moisture distribution, which was investigated in tomato (Solanum lycopersicum). Similar results were found where gs decreased as [X-ABA]leaf increased, but again the ABA response was attenuated. Furthermore, stomata showed similar sensitivity to ABA under both irrigation treatments. However, similar results were found for root tissue ([ABA]root) and xylem ([X-ABA]root) ABA, and modelling revealed that both localised root water uptake and soil moisture content are important for explaining the variation in [X-ABA]root between irrigation treatments. This research furthers the fundamental understanding of ABA signalling and suggests that irrigation frequency can be altered for a short period of the growing cycle to deliver specific grower objectives.

Research conducted over the past decade has highlighted the potential for improvements to rainfed agriculture and water productivity through the use of water harvesting, particularly for small-scale farmers in developing countries. However, empirical evidence indicates that projected adoption rates and hence crop yield and livelihood improvements have not been realised. This research argues that low adoption levels can be explained by the lack of emphasis on the context within which the technologies are placed by researchers and developmental organisations that promote them. This research uses an extended sustainable rural livelihoods approach to investigate the factors that support or constrain households’ abilities to benefit from the potential productivity increases offered by water harvesting. A livelihoods perspective is adopted to explore the similarities and differences in opportunities and constraints between different types of farmers both across and within households. Data presented here were collected during two extended periods of fieldwork in Burkina Faso, West Africa, during 2012 and 2013. An in-depth household level study was conducted across three case study villages, complemented by focus group discussions and key informant interviews. Insights demonstrate that livelihood choices, behaviours and priorities, asset access and control, risk context and utilisation of agricultural production are vital considerations in the assessment of the ability of water harvesting to increase agricultural productivity and/or improve livelihoods for any particular individual, household or community. The influence of these factors on benefits of adoption varies with wealth, gender and age at household level, with female farmers likely to experience the greatest constraints to production and livelihood improvements within households. This research argues that there is great potential to increase the crop and livelihood impact of water harvesting, particularly in poorer households and for women across all households, if a more holistic innovation systems approach is taken to their design and implementation.

This thesis presents the results of an investigation into the transport of water through soil from a pervaporative irrigation tube. This irrigation system uses a selective polymer membrane that allows water to cross by the process of pervaporation, which releases water into the soil in vapour phase. The polymer membrane is formed into a tube, buried in the soil and filled with saline water. The selectivity of the membrane retains salt within the tube whilst water is released, so the system treats the water and distributes it for irrigation simultaneously. The distribution of water from the system, rather than the treatment efficiency, was the focus of this project. Although in the field the system will interact with the plants it irrigates, in this work, for simplicity, plants were neglected. Instead a series of laboratory experiments were conducted to quantify the flux from the pervaporative tube in different soil types and in different humidity conditions. The results of these experiments highlighted, for the first time, the significance of vapour flow and condensation in the soil during the pervaporative irrigation process. Soil types with high water sorption at low relative humidity (e.g. saline sand) had an increased amount of condensation in the soil which resulted in an increased flux from the pipe. A moisture sorption isotherm was a useful predictor of this behavior. A numerical model was then developed to simulate the experimental findings. Experimental results had demonstrated that diffusion and condensation of water vapour through the soil were significant processes hence these were the main focus of the modelling work. Liquid flow was also simulated when the water content in the soil was sufficient. To simplify the representation of the pervaporative tube it was assumed that the membrane acted as a 100% humidity boundary in the soil thus it was assumed that it was the transport of water through the soil that limited the flux of water from the pervaporative tube rather than the membrane structure itself. The similarity between the observed and simulated results supported the basis of this conceptual understanding of pervaporative irrigation. This research raises a number of further questions regarding the interaction between plants and pervaporative membranes. These include how plants might interact with vapour flows through the soil and the influence of soil salinity on the interaction between the pervaporative membrane and the plant roots.

Cette thèse traite du développement et des mutations de l’industrie des engrais dans l’estuaire de la Loire à l’époque contemporaine sur le temps long entre 1820 et 1970. Elle se situe à la jonction de plusieurs thématiques : l’industrie chimique, les ports, l’agronomie et l’industrialisation d’un territoire. Elle articule trois entités, correspondant à trois niveaux d’échelle : un territoire portuaire, des usines et un produit, l’engrais. A ces entités correspondent des organisations : l’Etat et les autorités portuaires, des structures industrielles et un marché. Elle met en lumière la dynamique du développement et des mutations des filières de production d’engrais en territoire portuaire sous l’influence de multiples acteurs et institutions intéressés par le produit engrais (agronomes, agriculteurs, chimistes, Etat, hygiénistes, fabricants d’engrais, négociants, chambre de commerce, autorités portuaires, …). Elle caractérise les processus d’industrialisation à travers les diverses configurations de l’industrialisation portuaire en termes de structures industrielles, d’implantation territoriale des usines, de filières de production d’engrais, de trafic portuaire (importation, exportation) et d’aménagements portuaires. Elle montre, enfin, les ruptures et les filiations des différentes formes d’engrais et insiste sur les changements de représentation de l’engrais composé, le fil rouge de cette histoire. / This thesis deals with fertilizer industry development and changes in the Loire estuary in the contemporary era over the long period between 1820 and 1970. It is at the junction of several themes: the chemical industry, ports, agronomy and territory industrialization. It articulates three entities, corresponding to three levels of scale: a port territory, factories and a product, fertilizer. To these entities correspond organizations: state and port authorities, industrial structures and a market. It highlights development and changes dynamics in fertilizer production chains in port territory under the influence of multiple actors and institutions interested in the fertilizer product (agronomists, farmers, chemists, state, hygienists, fertilizer manufacturers, trader, chamber of commerce, port authorities, ...). It characterizes various configurations of port industrialization in terms of territorial establishment of factories, fertilizer production chains, port traffic (import, export) and port facilities. It shows, finally, the breaks and filiations of the different forms of fertilizer and insists on the changes of representation of the compound fertilizer, the red thread of this history.

Zur Umsetzung der EU-WRRL in der Landwirtschaft wurden in Sachsen seit 2009 in Gebieten mit erhöhtem Handlungsbedarf Arbeitskreise mit landwirtschaftlichen Unternehmen eingerichtet. Ziel ist es, den guten ökologischen und chemischen Zustand der Gewässer und des Grundwassers zu erreichen. In den sogenannten prioritären Gebieten wurden Praxisdemonstrationen zu Verfahren zur Reduzierung diffuser Stoffeinträge angelegt, untersucht und ausgewertet. Der Bericht fasst die Ergebnisse zusammen und enthält Handlungsanleitungen für Landwirte z. B. zum Einsatz von organischen Düngern mit und ohne Nitrifikationshemmstoffen, zur Streifenbearbeitung sowie zum Anbau von Zwischenfrüchten und Untersaaten.

Ancient settlements in Oman are frequently found where crops can be cultivated with groundwater distributed to fields by gravity flow. These irrigation systems are called aflāj (s. falaj), and they are still pivotal to community life: in 1997 over 3000 such systems were still in use. The allocation of falaj water among farmers traditionally depended on the use of the sun and the stars to track the passage of time. This practice, and particularly the use of stars, is disappearing rapidly: the availability of watches since c. 1970 means that there is now little technical reason to use the stars. The study records fast disappearing information on the ethnography of agricultural communities in northern Oman and, in particular, on the use of stars. It aims to identify the stars used and record the methods of stargazing in sufficient detail that the systems could be replicated if all local knowledge were lost. It also aims to raise awareness and improve the understanding of the significance of the traditional use of the stars in irrigated agriculture. This aspect of the cultural heritage of the region has not been written about previously in such detail. The research questions concern how, where and why stars are still used. There are several documents on falaj building and organisation in Oman, but relatively little on telling the time, and much less on the stars than on the use of the sun. The available documents were reviewed, but the main source for this study is data collected in the field, interviewing falaj managers and stargazers and watching the stars with them. Field work was carried out in different seasons since the stars used vary through the year. International experts were consulted on various aspects of the work, including Daniel Varisco on folk astronomy and Paul Kunitzsch on star names. The study focuses on five settlements where stars are used to this day. These are Qarya Beni Subh (Qarya), close to the mountains near the town of Al Hamra in the Interior Region; Al Fath, Zahib, Sudayra and Barzaman near the towns of Mudaybi and Sinaw in the Eastern Region. Additional information was obtained from a few other places for comparison, and during the course of the research it was found that only about eight of three thousand active falaj communities still use stars for time keeping. The methods of stargazing are given in detail, together with the names of the stars in Oman and their international classification where possible. It was found that the number of stars, the stars used, and their names in Oman vary from place to place. The time that each star represents is more variable than expected from the difference in length of night during the year. The stars used for falaj purposes are compared with those used in the region for navigation and with the stations of the moon of the Islamic calendar, but no evidence of any link between them was identified. On the basis of the history of falaj systems in Oman, the star names and the stars used, at least two of which are from the pre-Islamic Bedu tradition, it is concluded that the system of stargazing for timing water dates from pre-Islamic times, before the introduction of the stations of the moon. The main reason for the continued use of stars by a few communities, even though wristwatches are now widely available, is thought to be adherence to tradition both for its own sake and to avoid disputes over the sharing of water. It is considered unlikely that this ancient practice will survive more than 10 or 20 years unless the younger generation takes an interest in learning, and putting into practice, the traditions of their forefathers.