Stefan Liersch

A fuzzy GIS-based system to integrate local and technical knowledge in soil salinity monitoring

The increasing awareness of the complexity and uncertainty of environmental processes is changing the role of information production to support decision-making. Monitoring systems need to gather reliable information, adopting a multi-scale and integrated approach. Using exclusively technical monitoring methods to collect the information could result in unsustainable monitoring costs. In order to minimize the costs and to address the scale issue, the integration of local and technical knowledge is proposed in this work. For the implementation of this approach, a tool based on the use of fuzzy logic and geographic information system (GIS) technologies was developed. The willingness of the local community to participate in monitoring activities was ensured by keeping these activities as simple and close to local knowledge as possible. The fuzzy GIS-based system enhances both the comprehensibility of the local knowledge for the decision-makers and its reliability, making it usable for the decision-making process. The tool was developed to support soil salinity monitoring in the lower Amudarya River Basin in Uzbekistan.

Evaluation of an ensemble of regional hydrological models in 12 large-scale river basins worldwide

In regional climate impact studies, good performance of regional models under present/historical climate conditions is a prerequisite for reliable future projections. This study aims to investigate the overall performance of 9 hydrological models for 12 large-scale river basins worldwide driven by the reanalysis climate data from the Water and Global Change (WATCH) project. The results serve as the basis of the application of regional hydrological models for climate impact assessment within the second phase of the Inter-Sectoral Impact Model Intercomparison project (ISI-MIP2). The simulated discharges by each individual hydrological model, as well as the ensemble mean and median series were compared against the observed discharges for the period 1971–2001. In addition to a visual comparison, 12 statistical criteria were selected to assess the fidelity of model simulations for monthly hydrograph, seasonal dynamics, flow duration curves, extreme floods and low flows. The results show that most regional hydrological models reproduce monthly discharge and seasonal dynamics successfully in all basins except the Darling in Australia. The moderate flow and high flows (0.02–0.1 flow exceedance probabilities) are also captured satisfactory in many cases according to the performance ratings defined in this study. In contrast, the simulation of low flow is problematic for most basins. Overall, the ensemble discharge statistics exhibited good agreement with the observed ones except for extremes in particular basins that need further scrutiny to improve representation of hydrological processes. The performances of both the conceptual and process-based models are comparable in all basins.

Integrating local and technical knowledge to support soil salinity monitoring in the Amudarya river basin

The role of monitoring is changing due to the increasing awareness of complexity and uncertainty in environmental resources management. Monitoring systems are required to support critical reflection about the effectiveness of actions toward the achievement of management objectives. To this aim, monitoring should be based on a strong integrated and multi-scale approach. Monitoring costs could be prohibitive if the monitoring is only based on traditional scientific methods of measurements. To deal with these issues, the design of an innovative monitoring system should be based on the integration between different sources of knowledge and information. In this work the usability of local knowledge to support environmental monitoring is investigated. A multi-step participatory monitoring design process has been implemented aiming to design a program for soil salinity monitoring in the lower Amudarya river basin in Uzbekistan. Although there is an increasing awareness of the importance of stakeholders being involved in decision processes, the current socio-cultural and institutional context is not favourable to the participatory approach. The choice of method to be implemented in this work was influenced by such conditions. The analysis of the lessons learned from the experiences gained in this project revealed some important clues concerning the development of a locally-based monitoring program. These lessons can be subdivided according to three fundamental issues: the long term involvement of local community members in monitoring activities, the acceptance of locally-based monitoring systems by decision makers, and the reliability of monitoring information.

Modelling climate and land-use change impacts with SWIM: lessons learnt from multiple applications

Abstract The Soil and Water Integrated Model (SWIM) is a continuous-time semi-distributed ecohydrological model, integrating hydrological processes, vegetation, nutrients and erosion. It was developed for impact assessment at the river basin scale. SWIM is coupled to GIS and has modest data requirements. During the last decade SWIM was extensively tested in mesoscale and large catchments for hydrological processes (discharge, groundwater), nutrients, extreme events (floods and low flows), crop yield and erosion. Several modules were developed further (wetlands and snow dynamics) or introduced (glaciers, reservoirs). After validation, SWIM can be applied for impact assessment. Four exemplary studies are presented here, and several questions important to the impact modelling community are discussed. For which processes and areas can the model be used? Where are the limits in model application? How to apply the model in data-poor situations or in ungauged basins? How to use the model in basins subject to strong anthropogenic pressure? Editor D. Koutsoyiannis; Associate editor C. Perrin

Integrating water resources management in eco-hydrological modelling.

In this paper the integration of water resources management with regard to reservoir management in an eco-hydrological model is described. The model was designed to simulate different reservoir management options, such as optimized hydropower production, irrigation intake from the reservoir or optimized provisioning downstream. The integrated model can be used to investigate the impacts of climate variability/change on discharge or to study possible adaptation strategies in terms of reservoir management. The study area, the Upper Niger Basin located in the West African Sahel, is characterized by a monsoon-type climate. Rainfall and discharge regime are subject to strong seasonality. Measured data from a reservoir are used to show that the reservoir model and the integrated management options can be used to simulate the regulation of this reservoir. The inflow into the reservoir and the discharge downstream of the reservoir are quite distinctive, which points out the importance of the inclusion of water resources management.

Participatory Research for Adaptive Water Management in a Transition Country - a Case Study from Uzbekistan

Participatory research has in recent years become a popular approach for problem-oriented scientific research that aims to tackle complex problems in a real management context. Within the European Union project NeWater, stakeholder processes were initiated in seven case studies to develop approaches for adaptive water management. The Uzbek part of the Amudarya River basin was one of the studied river basins. However, given the current political and cultural context in Uzbekistan, which provides little room for stakeholder participation, it was unclear to what extent participation could be realized there. In this paper, we present an evaluation of the participatory research carried out in the Amudarya case study with respect to (i) the choice and application of different participatory methods and their adaptation to the given political, socioeconomic, and cultural environment, (ii) their usefulness in improving system understanding and developing strategies and measures to improve water management and monitoring, and (iii) their acceptance and suitability for enhancing policy-making processes in the Amudarya River basin context. The main lessons learned from the comparison of the different participatory methods were (1) the stakeholder process provided an opportunity for meetings and discussions among stakeholders from different organizational levels and thus promoted communication between different levels and organizations, and (2) in a context where most stakeholders are not generally involved in policy-making, there is a danger of raising expectations that a research project cannot meet, e.g., of transferring local interests to higher levels. Our experience shows that in order to choose participatory methods and adapt them to the Uzbek cultural and political setting (and most likely this applies to other post-Soviet transition countries as well), four aspects should be taken into account: the time required to prepare and apply the method, good information about the participants and the context in which the method will be applied, knowledge of the local language(s), and careful training of local moderators. While these aspects are relevant to any application of participatory methods, they become even more important in a political and socio-cultural setting such as that found in Uzbekistan. One added value of the activities and a crucial aspect of a participatory research processes was the capacity building of local scientists and practitioners, which facilitates the further application of the methods.

Inter-model comparison of hydrological impacts of climate change on the Upper Blue Nile basin using ensemble of hydrological models and global climate models

The aim of this study was to investigate the impacts of future climate change on discharge and evapotranspiration of the Upper Blue Nile (UBN) basin using multiple global circulation models (GCMs) projections and multiple hydrological models (HMs). The uncertainties of projections originating from HMs, GCMs, and representative concentration pathways (RCPs) were also analyzed. This study is part of the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP) initiative (phase 2), which is a community driven modeling effort to assess global socio-economic impacts of climate change. The baseline period of 1981–2010 was used to identify climate change signals in two future periods: mid future (2036–2065) and far future (2070–2099). Our analyses showed that two out of four GCMs indicated a statistically significant increase in projected precipitation in the far future period. The projected change in mean annual precipitation varied between 4 and 10% relative to the baseline period. The HMs did not agree on the direction of climate change impacts on mean annual discharge. Furthermore, simulated changes in mean annual discharge by all HMs, except SWIM which simulated up to 6.6% increase for the far future period, were not statistically significant. All the HMs generally simulated a statistically significant increase in annual mean actual evapotranspiration (AET) in both periods. The HMs simulated changes in AET ranging from 1.9 to 4.4% for the far future period. In the UBN basin GCM structure was the main contributor of uncertainty in mean annual discharge projection followed by HM structure and RCPs, respectively. The results from this research suggest to use multiple impact models as well as multiple GCMs to provide a more robust assessment of climate change impacts in the UBN basin.

Scenarios of climate and land-use change,water demand and water availability for the São Francisco River basin

RBCIAMB | n.36 | jun 2015 | 96-114 ABSTRACT In this study, scenarios of changes in land-use patterns, agricultural production and climate, and their effects on water demand and availability in the São Francisco river basin (Brazil) are analysed. The global driver population growth, economic development, and trade liberalization are included. Using the regionalized version of a global agro-economic landand water use model, impacts are analysed for two scenarios: a regionalized world with slow economic development, high population growth, and little awareness of environmental problems (A2), and a globalized world with low population growth, high gross domestic product (GDP) growth, and environmental sustainability (B1). A regional ecohydrological model is used to analyse the effect of these scenarios on water demand and availability. The climate scenarios in general show a wetter future (years 2021 – 2050), with wetter rainy seasons and drier dry seasons. The water availability for irrigated agriculture is high, while hydropower generation is declining by 3.2% (A2) and 1.7% (B1) compared to the reference.

Erratum to: Evaluation of an ensemble of regional hydrological models in 12 large-scale river basins worldwide

Evaluation of an ensemble of regional hydrological models in 12 large-scale river basins worldwide (vol 141, pg 381, 2017)

Coupling land-use change and hydrologic models for quantification of catchment ecosystem services

Abstract Representation of land-use and hydrologic interactions in respective models has traditionally been problematic. The use of static land-use in most hydrologic models or that of the use of simple hydrologic proxies in land-use change models call for more integrated approaches. The objective of this study is to assess whether dynamic feedback between land-use change and hydrology can (1) improve model performances, and/or (2) produce a more realistic quantification of ecosystem services. To test this, we coupled a land-use change model and a hydrologic mode. First, the land-use change and the hydrologic models were separately developed and calibrated. Then, the two models were dynamically coupled to exchange data at yearly time-steps. The approach is applied to a catchment in South Africa. Performance of coupled models when compared to the uncoupled models were marginal, but the coupled models excelled at the quantification of catchment ecosystem services more robustly.