Stefan Liehr

Institute for Social-Ecological Research | ISOE · Water Resources and Land Use

Wildlife numbers are declining globally due to anthropogenic pressures. In Namibia, however, wildlife populations increased with policy instruments that allow private ownership and incentivize their sustainable use. Antithetically, this resulted in increased resource competition between humans and wildlife and triggered conflicts among various stak...

Nomadic pastoralism is of vital importance for grasslands worldwide. As one of the largest, widely intact, temperate grasslands in the world, the eastern Mongolian steppe looks back on a millennia-old tradition of nomadic pastoralism. Thus, this type of use of the ecosystem plays an important role in providing and maintaining ecosystem functions, e...

Sudden regime shifts or tipping points pose a major threat to various ecosystems and people's livelihoods worldwide. However, tipping points are still hard to predict and often occur without warning. To avoid dramatic social-ecological consequences, it is crucial to understand tipping point behaviour and to identify early warning indicators. Previo...

Physical components of societies like infrastructures need biophysical resources for their construction, maintenance and use. These components, analyzed as societies' material stocks, predefine energy and raw materials and provide societal services, necessary for their functioning and for social welfare. The nexus between stocks, the resource flows...

CONTEXT In Madagascar land use pressure on natural resources has increased drastically over the last decades. For subsistence farmers this situation often leads to an accelerated unsustainable exploitation of resources with negative consequences for their livelihood, which can be described as a social-ecological trap (SET). OBJECTIVE Our paper see...

This conflict analysis is a product of the project “Weschnitz Dialog”, funded by the “The German Federal Environmental Foundation (Deutsche Bundesstifung Umwelt DBU)” which was carried out on behalf of the “Gewässerverband Bergstraße” under the leadership of ISOE from 2019 to 2021. The analysis investigates a current conflict regarding the dike res...

Non-technical summary Investing in stricter biodiversity conservation and wildlife protection to reduce the number of emerging diseases and, consequently, the risk of pandemics such as coronavirus disease-19 (COVID-19), must integrate a social-ecological perspective. Biodiversity conservation, in order to be effective as disease prevention, require...

The Global South is facing severe challenges in ensuring livelihood security due to climate change impacts, environmental degradation and population growth as well as changing lifestyles. These complex problems cannot be solely solved by single scientific disciplines – they require transdisciplinary research (TDR). Stakeholders from civil society,...

Precautionary measures and governmental regulations during the COVID-19 pandemic’s first wave have drastically altered daily activities and hence water consumption patterns. Many people had to change their working routines, the organization of childcare and hygiene practices. While first evidence appears on the impacts of COVID-19 on, e.g., carbon...

Sozial-ökologische Transformationen können nur gelingen, wenn wir sie als gemeinsame Gestaltungsaufgabe verstehen. Doch wie kann gemeinsames Handeln gefördert werden, wenn die Vorstellungen von einem „guten Leben“ so unterschiedlich sind? Die hier vorgestellten Gestaltungsprinzipien sollen transdisziplinärer Nachhaltigkeitsforschung Orientierung ge...

Social-ecological transformations can only succeed if we understand them as a joint task of shaping the future. But how can joint action be fostered when ideas of the "good life" differ so much? The principles of shaping presented here aim to provide orientation for transdisciplinary sustainability research in order to find answers to complex quest...

India is booming! The people of this predominantly rural emerging economy are increasingly moving to the economically important conurbations resulting in sprawling urban centres challenged to keep up with adequate infrastructure development. While in 2016 about one third of India’s 1.31 billion inhabitants lived in cities, the urban population will...

Droughts threaten millions of people in Sub-Saharan Africa, leading to famines, water shortages, migration and casualties. Climate change will most probably exacerbate the devastating consequences as exceptional droughts are expected to occur more frequently. Conventional drought risk assessments however, do not provide adequate tools, as they ofte...

23. – 24. July 2019, Windhoek, Namibia

With 1.7 million inhabitants on an area of 257 square kilometres, Coimbatore city (Tamil Nadu) is one of the over 50 typical industrial cities with more than a million inhabitants in India. It is estimated that the population of the South Indian city will grow by another million people over the next 30 years. Securing the water supply and wastewate...

Coimbatore faces rapid growth in the next decades, increasing the pressure on natural resources and the need to secure water, energy, and food supplies. As one of India’s 100 Smart Cities, Coimbatore has the chance to realize exemplary solutions and set the course for a sustainable urban development. The project Smart Water Future India (SWF India)...

The Eastern Steppe of Mongolia is one of the world's largest mostly intact grassland ecosystems and is characterised by a close coupling of societal and natural processes. In this ecosystem, mobility is one of the key characteristics of wildlife and human societies alike. The current economic development of Mongolia is accompanied by extensive soci...

Water scarcity is an essential threat to the sustainable development pathways of countries in the Global South. In southern Africa for instance, hydro-climatic conditions are already critical but are likely to become worse as climate change projections indicating more severe droughts, un-certain rainfall conditions and a likely temperature increase...

Droughts threaten many regions worldwide, in particular semi-arid environments of sub-Saharan Africa such as the Cuvelai-Basin in Angola and Namibia, as the population depends on critical water-related ecosystem services. Since droughts are multi-layered phenomena, risk assessment tools that capture the societal relations to nature and identify tho...

Good quality data on precipitation are a prerequisite for applications like short-term weather forecasts, medium-term humanitarian assistance, and long-term climate modelling. In Sub-Saharan Africa, however, the meteorological station networks are frequently insufficient, as in the Cuvelai-Basin in Namibia and Angola. This paper analyses six rainfa...

Good quality data on precipitation are a prerequisite for applications like short-term weather forecasts, medium-term humanitarian assistance and long-term climate modelling. In Sub-Saharan Africa however, terrestrial climate station networks are frequently insufficient as in the Cuvelai-Basin in Namibia and Angola. As part of SASSCAL task 16, this...

The book consolidates the transdisciplinary research of the project “CuveWaters: Integrated Water Resources Management in Central Northern Namibia (Cuvelai Basin) in the SADC-Region”, funded by the German Federal Ministry for Education and Research (BMBF) and undertaken from 2004 to 2015 in Namibia. In these eleven years it was possible to accompli...

Die Kopplung von grauen, grünen und blauen Infrastrukturen als Maßnahme zur Anpassung an den Klimawandel kann im Zusammenspiel der städtischen Akteure urbane Lebensqualität erhöhen und ist zugleich ein Baustein zur infrastrukturellen Transformation.

Current state of the household drought risk research in task16 of SASSCAL.

Drought is one of the major threats to societies in Sub-Saharan Africa, as the majority of the population highly depends on rain-fed subsistence agriculture and traditional water supply systems. Hot-spot areas of potential drought impact need to be identified to reduce risk and adapt a growing population to a changing environment. This paper presen...

The sustainability discourse is, essentially, centered on the question of how complex relations between nature and society can be conceptualized, analyzed and shaped. In this paper, we present a specific interpretation of social ecology as an attempt to address this question. For this purpose, we establish Frankfurt Social Ecology (FSE) as a formal...

Research aimed at contributing to the further development of integrated water resources management needs to tackle complex challenges at the interface of nature and society. A case study in the Cuvelai-Etosha Basin in Namibia has shown how semi-arid conditions coinciding with high population density and urbanisation present a risk to people's livel...

Transformation has become a major topic of sustainability research. This opens up new perspectives, but at the same time, runs the danger to convert into a new critical orthodoxy which narrows down analytical perspectives. Most research is committed towards a political-strategic approach towards transformation. This focus, however, clashes with ong...

The poster examines the qualitative empirical insights on household decision making in northern Namibia concerning livestock management. Continuous and planned grazing is presented as two key strategies.

Urban areas of developing countries face the challenge to implement adequate water and sanitation infrastructures while using natural and financial resources sustainably. The objective of this study was to identify benefits and challenges of different nutrient and water reuse systems. For this, we evaluated and compared four systems; (1a) the local...

In 2010, there was a bold commitment to take action in halting global biodiversity loss by 2020. Now, half way through the Convention on Biological Diversity strategic plan 2011–2020, the success of the mission is under discussion. With the Twelfth Conference of the Parties attesting a lack of action, attention is now focused on the science–policy...

The article describes the approach of integrated water research, in particular its overall design, the use of suitable procedures and methods, and the dissemination of its results. Based on four case studies from the German water sector, focusing on water demand forecasting, assessment of technical options, improvement of user acceptance and the se...

Die vorgestellte Wasserbedarfsprognose für das Versorgungsgebiet von HAMBURG WASSER bis zum Jahr 2045 basiert auf einem verbrauchergruppenspezifischen und teilräumlichen Analyse-­ und Prognoseansatz. Durch Verschneidung von Wasserverbrauchs­ mit Geoinformationsdaten zu sozial-­, wirtschafts-­ und siedlungsstrukturellen Aspekten bis hinunter zur Adr...

Namibia is the most arid country in Sub-Saharan Africa. The Cuvelai-Etosha Basin (CEB) in central northern Namibia in particular is experiencing various ecological and social-ecological challenges such as high climate variability, saline groundwater, dependence on Angola for freshwater supply, high population growth and density, and increasing urba...

The majority of the rural population in the West African Sahel depends on subsistence and small-scale farming. Thus, climate change, with its increasing temperatures and rainfall variability, impacts the environment and poses considerable risks to livelihoods. Given these circumstances, migration can be an important strategy for coping with the cha...

Adequate sanitation, wastewater treatment and irrigation infrastructure often lacks in urban areas of developing countries. While treated, nutrient-rich reuse water is a precious resource for crop production in dry regions, excessive salinity might harm the crops. The aim of this study was to quantify, from a system perspective, the nutrient and sa...

A water demand forecast for the service area of HAMBURG WASSER until the year 2045 is presented. The forecast approach is user group specific and includes spatial analysis. Water consumption data is intersected with geospatial information about aspects of social, economic and settlement structure. Major factors on the specific water demand within t...

Factsheet on Rainwater Harvesting in central-northern Namibia

Factsheet on Floodwater Harvesting in centra-northern Namibia

In order to understand the impact of climatic and environmental changes as well as socio-economic drivers on human migration, it remains a challenging task to find a method to analyse the knowledge from different scientific disciplines in an integrated way. The Sahel region with its high ecological dynamic has a long history of migratory movements....

Namibian savannas are characterised by a variable climate and are systems in which societal processes are inextricably coupled with natural processes through land management and the benefits that people derive from the ecosystem. Savannas are home to a large proportion of the world’s human population, and any disruption to the balance between these...

The design of rainwater harvesting based gardens requires considering current climate but also climate change during the lifespan of the facility. The goal of this study is to present an approach for designing garden variants that can be safely supplied with harvested rainwater, taking into account climate change and adaptation measures. In additio...

Drought is a recurring threat to the inhabitants of the Cuvelai watershed in Namibia and Angola. This is especially true for rural households whose livelihood depends on subsistence agriculture. This paper presents the results of a qualitative household survey to understand the impact of drought and identify key parameters that determine households...

Water storage at a small-scale level and water reuse at a municipal level reduce dependence from climate variations and from the effects of climate change, such as higher rainfall variability and longer dry spells. Water storage and reuse thus contribute to regional water security. Water storage and reuse, together with agricultural production, sho...

Wasserbedarfsprognosen sind für Wasserversorger eine wichtige Entscheidungsgrundlage für zukünftige Maßnahmen in der wirtschaftlichen und technischen Betriebsführung sowie beim Ressourcenmanagement. In den letzten zwei Jahrzehnten sanken in Deutschland die spezifischen Wasserbedarfe aufgrund von Technik- und Verhaltensinnovationen. Für Regionen mit...

Treating and reusing municipal wastewater for urban agriculture raises water productivity. This paper developed a methodology to quantify water flows and productivity of a proposed infrastructure including water supply, sanitation, wastewater treatment and water reuse for agriculture. The methodology consists in calculating the pathogen reduction a...

This assessment concept paper provides a methodological approach for the formative assessment and summative assessment of GIZ’s International Water Stewardship Programme (IWaSP) and its component partnerships. IWaSP promotes partnerships between the private sector (corporations and SMEs), the public sector and the society to tackle shared water ris...

Die Wasserbedarfsprognose für das Versorgungsgebiet von HAMBURG WASSER bis zum Jahr 2045 basiert auf einem verbrauchergruppenspezifischen und teilräumlichen Analyse- und Prognoseansatz. Durch Verschneidung von Wasserverbrauchs- mit Geoinformationsdaten zu sozial-, wirtschafts- und siedlungsstrukturellen Aspekten bis hinunter zur Adressebene wurden...

Hydrological extreme events like droughts and floods are recurring hazards in central-northern Namibia. In particular smallholders are threatened since their livelihoods highly depend on reliable hydrological conditions. The local social-ecological system, characterized by subsistence farming and livestock herd-ing, is able to deal with change in h...

Global change is challenging communities all over the African continent with varying intensities. In particular, central-northern Namibia is confronted with changing rainfall patterns, land use change, population growth and urbanization, leading to an overuse of scarce land- and water resources. Especially, rural subsistence farmers are threatened...

North-central Namibia is characterized by seasonal alterations of drought and heavy rainfall, mostly saline groundwater resources and a lack of perennial rivers. Water scarcity poses a great challenge for freshwater supply, harvest and food security against the background of high population growth and climate change. CuveWaters project aims at pove...

1. Based on studies on specific countries already on hand and on the actual networks for export orientation and also using the published long-term scenarios dealing with the global water situation, a look was taken at how the preconditions for success for the German water industry can be improved and how the existing innovation potentials can be be...

This paper presents main findings of a feasibility study for a joint transdisciplinary project to strengthen the implementation of integrated water resources management (IWRM) in the Cuvelai Basin, northern Namibia. The region is characterised by seasonal alterations of droughts and heavy rainfall, mostly saline groundwater and a lack of permanent...

New and promising paths in the design of forecasting systems of future water demand are opened up by up-to-date methods for data collection, field research and analysis of databases in combination with innovative concepts of integrating these results and forecasting future developments. Geographic information systems and improved distinctions of wa...

The utilisation of natural resources is indispensable to the safeguarding of societal activities. Nevertheless, the sustainable management of such resources involves a constant confrontation with new processes of change and the challenges that go with them. In view of economic concentration, socio-structural and demographic developments, global cha...

The prediction of switching dynamical systems requires an identification of each individual dynamics and an early detection of mode changes. Here we present a unified framework of a mixtures of experts architecture and a generalized hidden Markov model (HMM) with a state space dependent transition matrix. The specialization of the experts in the dy...

Mensch und Umwelt - ein Blick auf die aktuellen Debatten zu Problemfeldern wie Klima-, Energie und Wasserpolitik macht deutlich, in welch engem Maße gesellschaftliche und natürliche Prozesse miteinander verknüpft sind. Umwelt- probleme sind daher auch gesellschaftliche Probleme und die Erlangung eines tiefgreifenden Verständnisses der relevanten Pr...

Assuming that financial markets behave similar to random walk processes we derive a trading strategy with variable investment which is based on the equivalence of the period of bankruptcy risk and the risk to profit ratio. We define a state dependent predictability measure which can be attributed to the deterministic and stochastic components of th...

Assuming that financial markets behave similar to non-stationary random walk processes we derive an optimal trading strategy with variable investment for minimizing the risk to profit ratio over the trading period. We define a predictability measure which can be attributed to the deterministic and stochastic components of the price dynamics. The in...

this paper. A detailed comparison of the results, however, goes beyond the scope of this contribution.