This paper assesses the sustainability of bioenergy production under a nexus perspective through a new efficiency type index. The index describes 1st generation biofuel production under the perspective of the implied consumption of natural resources. We consider the sustainability of energy production as a sequence of steps, each characterised by its efficiency, and propose an index which returns an overall efficiency value describing the adequacy or inadequacy of the considered processes under a nexus perspective. The direct application of the nexus index entails an indication of the possible improvements needed to move production towards most sustainable processes or places. Moreover, it allows evaluating the efficiency of the main crops currently used in biofuel production with respect to the water–food–energy nexus. The results depict countries presently capable of performing sustainable production of 1st generation biofuel from particular crops. Furthermore, the analysis of the single components of the nexus index allows understanding the effects of possible improvements (e.g. soil and water management, new generation biofuels) on the overall production efficiency under a nexus perspective.

With the notion of the Water-Energy-Food Nexus long neglected interlinkages between water, energy, and food are becoming visible. Yet, the diversity in understandings of the Nexus (as an analytical tool and political agenda) is the starting point for our research interest, stemming as it does from a governance perspective. The contributions of this special issue highlight different facets of governance around the Nexus. While some papers attempt to conceptualize the Nexus-Governance further, others clearly have an empirical focus. Thereby this special issue provides a rich body of work for further WEF-Nexus studies and integrative policies, such as the SDGs.

The majority of rural Indian households remain dependent on traditional, inefficient and harmful household energy technologies. Rural households make their energy decisions with respect to the Water-Energy-Food security (WEF) Nexus jointly, however, previous research initiatives have analyzed household energy access problem in isolation. Taking this WEF nexus into account, this thesis investigates factors influencing household energy transition and identifies an optimal village energy system (VES) for the rural communities in Uttar Pradesh, India. The thesis also analyzes the distributional impacts of VES on different categories of rural households.<br /> Using detailed household survey data, Logit and Zoib (zero one inflated beta) regression techniques were applied to analyze household's activities and to identify factors influencing household energy transition. The results showed that regular non-agricultural income of household's male member increases the probability of household's modern cooking energy and modern lighting transition by 8.6% and 13.6%, respectively. It was found that household's higher agricultural dependence and resource endowments (more labor and cattle) lead to higher share of traditional bioenergy consumption in the total cooking energy mix. Proximity to markets and high household income were observed to positively influence household modern cooking and lighting transition. Local institutions such as local bio-energy markets and barter trade for labor- bioenergy were observed to have significant influence on household energy choice. Results also showed that government's policy instrument such as household connection to government LPG scheme is associated with 20.5% increased probability of household using modern cooking energy as its primary cooking fuel. Results also indicated that social factors such as higher female education and young age of household head are associated with household's increased modern cooking energy consumption in its total cooking energy mix.<br /> The thesis utilized linear optimization technique to formulate a village energy model in GAMS (General Algebraic Modeling Software). The model identified an optimal Village Energy System (VES) considering all possible energy sources and technologies (energy systems) as well as their linkages with food security. Results confirmed energy systems interdependencies for the rural communities. For instance, results showed that the levelized cost of electricity generation from biomass gasifier power system is 2.54 INR/ MJ as compared to 2.89 INR/ MJ from grid electricity-battery based power system. However, model selected the latter for fulfilling village's night time power needs while it assigned higher shadow price of 0.143 INR / MJ to the former. This happened because possible utilization of gasifier power system was expected to create scarcities of local bio-energy resources, resulting in costlier cooking energy system for the village. It was found that DES (Decentralized Energy System) provides demand side energy management opportunities with different energy prices at different timings of the day. Results also showed that high cost of finance deters possible adoption of renewable power technologies, such as solar power.<br /> Lastly, the thesis constructed an agricultural household model linked with VES to analyze VES's welfare consequences on rich and poor households. Here, household had the opportunity to purchase VES's energy services and sell its bio-energy feedstocks to VES. For the poor household, this interaction with VES led to its increased agricultural production with around 22% increase in its farm area cultivation in summers, as well as led to reduction in its off-farm labor by around 11% which is then utilized in its own agriculture. Overall, this interaction resulted in around 4% increase in poor household's annual income. On the down side, this interaction led to poor household shifting towards dirtier cooking energy technologies, resulting in increased external costs and CO2 emissions by around 27% and 45%, respectively. On the other hand, VES did not impact rich household's food production and only marginally increased its economic gain. However, it led to rich household shifting towards cleaner cooking energy thereby resulting in reduction of its external costs almost by half. | <strong>Dezentrale Energie in Indien und ihre Synergien mit der Wasser-Energie-Nahrungsmittelsicherheits (WEF) Nexus</strong><br /> Die Mehrheit der ländlichen indischen Haushalte ist auf traditionelle, ineffiziente und schädliche Haushalts-Energietechnologien angewiesen. Die Entscheidungsprozesse ländlicher Haushalte, wie Energie genutzt wird, wird in Bezug auf der Nexus Wasser-Energie-Nahrungsmittelsicherheit (WEF) getroffen. Jedoch haben die früheren wissenschaftlichen Analysen die Probleme des Energiezugangs von Haushalten selektiv und isoliert betrachtet. Unter Berücksichtigung des WEF-Nexus untersucht diese Arbeit Faktoren, die die häusliche Energiewende beeinflussen und entwickelt ein optimiertes Dorfenergiesystem (VES) für ländliche Gemeinden in Uttar Pradesh, Indien. Weiterhin analysiert die Arbeit die unterschiedlichen Auswirkungen des VES auf arme und reiche ländliche Haushalte.<br /> Mit Hilfe detaillierter Haushaltsumfragedaten wurden die Regressionsverfahren Logit und Zoib (zero one inflated beta) angewandt, um die häuslichen Aktivitäten zu analysieren und Faktoren zu identifizieren, welche die häusliche Energiewende beeinflussen. Die Ergebnisse zeigten, dass das regelmäßige nicht-landwirtschaftliche Einkommen des männlichen Haushaltsmitgliedes die Wahrscheinlichkeit, dass der Haushalt moderne Kochenergie und moderne Beleuchtung nutzt, um 8,6% bzw. 13,6% erhöht. Eine höhere landwirtschaftliche Abhängigkeit und die Ressourcenausstattung des Haushalts (mehr Vieh und Arbeiter) führen zu einem höheren Anteil des traditionellen Bioenergieverbrauchs am Kochenergiemix. Die Nähe zu den Märkten und das hohe Haushaltseinkommen haben sich positiv auf den Übergang zu modernen Haushalts-Energietechnologien ausgewirkt. Lokale Einrichtungen wie Bioenergiemärkte und der Tauschhandel (Arbeit für Bioenergie) haben einen signifikanten Einfluss auf die Energiewahl im Haushalt. Die Ergebnisse zeigten auch, dass das politische Instrument der Einbindung an das staatliche LPG-System zu einer um 20,5% höheren Wahrscheinlichkeit führt, dass der Haushalt moderne Kochenergie als primären Kochbrennstoff verwendet. Die Ergebnisse deuteten auch darauf hin, dass soziale Faktoren wie eine höhere Bildung von Frauen und ein junges Alter des Haushaltsvorstehers zu einem höheren Anteil moderner Energien am Kochenergiemix führen.<br /> Die Dissertation verwendet eine lineare Optimierungstechnik, um ein Dorf-Energiemodell in GAMS (General Algebraic Modeling Software) zu formulieren. Das Modell wählt ein optimales Village Energy System (VES) unter Berücksichtigung aller möglichen Energiequellen und Technologien sowie der Kopplung des Energiesystems mit der Ernährungssicherheit. Die Ergebnisse bestätigten die gegenseitigen Abhängigkeiten der Energiesysteme für die ländlichen Gemeinden. Die Ergebnisse zeigten zum Beispiel, dass die Stromgestehungskosten aus dem Biomassevergaser-Stromversorgungssystem 2,54 INR / MJ betragen, verglichen mit 2,89 INR / MJ aus dem Netzstrom-batteriebasierten Stromsystem. Das Modell entschied sich jedoch für Letzteres, um den nächtlichen Strombedarf des Dorfes zu decken, während es dem anderen System einen höheren Schattenpreis von 0,143 INR / MJ zuwies. Dies ist darauf zurückzuführen, dass eine mögliche Nutzung des Vergaserstroms dazu führen kann, dass Knappheiten lokaler Bioenergieressourcen entstehen, was zu einem teureren Kochenergiesystem. Es wurde festgestellt, dass DES (Decentralized Energy System) nachfrageorientierte Möglichkeiten des Energiemanagements bietet. Die Ergebnisse zeigen auch, dass hohe Finanzierungskosten eine mögliche Einführung erneuerbarer Energietechnologien verhindern.<br /> Abschließend entwickelte die Arbeit ein landwirtschaftliches Haushaltsmodell in Verbindung mit VES, um die Auswirkungen von VES auf reiche und arme Haushalte zu analysieren. Hier hatte der Haushalt die Möglichkeit, VES-Energiedienstleistungen zu kaufen und seine Bioenergie-Rohstoffe an VES zu verkaufen. Bei einem armen Haushalt führte diese Interaktion zu einer Steigerung der landwirtschaftlichen Produktion (ca. 22%) und einer Reduzierung der landwirtschaftlichen Arbeit in fremden Betrieben um ca. 11%. Alles zusammen führte zu einem Anstieg des Jahreseinkommens des armen Haushalts um ca. 4%. Andererseits führte dies dazu, dass die Kochenergietechnik armer Haushalte schmutziger wurde was zu erhöhten externen Kosten führte (ca. 27%). Demgegenüber wurde die Nahrungsmittelproduktion reicher Haushalte von VES nicht beeinflusst und erhöhte nur geringfügig den wirtschaftlichen Gewinn. Jedoch verlagerten sich reiche Haushalte in Richtung sauberer Kochenergien, wodurch die externen Kosten um fast die Hälfte reduziert wurden.

© 2018 Elsevier B.V. Accurately delineating the effects of hydrological and water quality habitat factors on the aquatic biota will significantly assist the management of water resources and restoration of river ecosystems. However, current models fail to comprehensively consider the effects of multiple habitat factors on the development of fish species. In this study, a dynamic framework for river ecosystems was set up to explore the effects of multiple habitat factors in terms of hydrology and water quality on the fish community in rivers. To achieve this the biomechanical forms of the relationships between hydrology, water quality, and aquatic organisms were determined. The developing processes of the food web without external disturbance were simulated by 208 models, constructed using Ecopath With Ecosim (EWE). These models were then used to analyze changes in biomass (ΔB) of two representative fish species, Opsariichthys bidens and Carassius auratus, which are widely distributed in Asia, and thus have attracted the attention of scholars and stakeholders, due to the consequence of habitat alteration. Results showed that the relationship between the changes in fish biomass and key habitat factors can be expressed in a unified form. T-tests for the unified form revealed that the means of the two data sets of simulated and observed ΔB for these two fish species (O. bidens and C. auratus) were equal at the significance level of 5%. Compared with other ecological dynamic models, our framework includes theories that are easy to understand and has modest requirements for assembly and scientific expertise. Moreover, this framework can objectively assess the influence of hydrological and water quality variance on aquatic biota with simpler theory and little expertise. Therefore, it is easy to be put into practice and can provide a scientific support for decisions in ecological restoration made by river administrators and stakeholders across the world.

The threat of climate change is emerging at a time of rapid growth for many economies in sub-Saharan Africa (SSA). Dominant narratives comprising ambitious development plans are common and often based around sectors with strong inter-dependencies that are highly exposed to climate variability. Using document analysis and key informant interviews, this article examines how climate change is addressed in policy, how it is being mainstreamed into water, energy and agriculture sector policies and the extent to which cross-sectoral linkages enable coordinated action. These questions are addressed through a case study of Tanzania, highlighting broader lessons for other developing countries, particularly those in SSA facing similar challenges. The article finds that, while the agriculture and water sectors are increasingly integrating climate change into policies and plans in Tanzania, practical coordination on adaptation remains relatively superficial. Publication of the Tanzania National Adaptation Plan of Action (NAPA) in 2007 marked a step change in the integration of climate change in sectoral policies and plans; however, it may have reinforced a sectoral approach to climate change. Examining the policies for coherence highlights overlaps and complementarities which lend themselves to a coordinated approach. Institutional constraints (particularly structures and resources) restrict opportunities for inter-sectoral action and thus collaboration is confined to ad hoc projects with mixed success to date. The results highlight the need for institutional frameworks that recognize and address these constraints to enable development goals to be pursued in a more sustainable and climate-resilient manner. KEY POLICY INSIGHTS The NAPA has been successful at encouraging climate change mainstreaming into sectoral policies in Tanzania; however, the cross-sectoral collaboration crucial to implementing adaptation strategies remains limited due to institutional challenges such as power imbalances, budget constraints and an ingrained sectoral approach. Collaboration between nexus sectors in Tanzania is largely through ad hoc projects with limited progress on establishing deeper connections to enable collaboration as a process. Regular cross-sectoral planning meetings and consistent annual budgets could provide a platform to enhance cross-sectoral coordination. Plans to develop hydropower and agriculture are prevalent across sub-Saharan Africa. Insights from Tanzania highlight the importance of institutional and policy frameworks that enable cross-sectoral coordination.