Lars Ribbe

Mobile devices for community-based REDD+ monitoring: a case study for Central Vietnam.

Monitoring tropical deforestation and forest degradation is one of the central elements for the Reduced Emissions from Deforestation and Forest Degradation in developing countries (REDD+) scheme. Current arrangements for monitoring are based on remote sensing and field measurements. Since monitoring is the periodic process of assessing forest stands properties with respect to reference data, adopting the current REDD+ requirements for implementing monitoring at national levels is a challenging task. Recently, the advancement in Information and Communications Technologies (ICT) and mobile devices has enabled local communities to monitor their forest in a basic resource setting such as no or slow internet connection link, limited power supply, etc. Despite the potential, the use of mobile device system for community based monitoring (CBM) is still exceptional and faces implementation challenges. This paper presents an integrated data collection system based on mobile devices that streamlines the community-based forest monitoring data collection, transmission and visualization process. This paper also assesses the accuracy and reliability of CBM data and proposes a way to fit them into national REDD+ Monitoring, Reporting and Verification (MRV) scheme. The system performance is evaluated at Tra Bui commune, Quang Nam province, Central Vietnam, where forest carbon and change activities were tracked. The results show that the local community is able to provide data with accuracy comparable to expert measurements (index of agreement greater than 0.88), but against lower costs. Furthermore, the results confirm that communities are more effective to monitor small scale forest degradation due to subsistence fuel wood collection and selective logging, than high resolution remote sensing SPOT imagery.

Statistical downscaling of precipitation and temperature in north-central Chile: an assessment of possible climate change impacts in an arid Andean watershed.

Abstract Downscaling of atmosphere–ocean general circulation models (AOGCMs) is necessary to transfer predictions of potential climate change scenarios to local levels. This is of special interest in dry mountainous areas, which are particularly vulnerable to climate change due to risks of reduced freshwater availability. These areas play a key role in hydrology, since they usually receive the highest local precipitation amounts, which are then stored in the form of snow and glaciers. The performance and ability to simulate extreme events of a statistical downscaling model (SDSM) were tested in the arid Upper-Elqui watershed, Chile. Thereafter, future temperature and precipitation seasonal trends along with agro-hydrological indices were analysed for the HadCM3 A2a and B2a scenarios. Maximum and minimum temperatures for both linear trends and extreme events were simulated accurately. However, the results show that SDSM was not a very robust method for the simulation of precipitation. Nevertheless, future trends and indices indicate possible strong inter-seasonal perturbations. Citation Souvignet, M., Gaese, H., Ribbe, L., Kretschmer, N. & Oyarzún, R. (2010) Statistical downscaling of precipitation and temperature in north-central Chile: an assessment of possible climate change impacts in an arid Andean watershed. Hydrol. Sci. J. 55(1), 41–57.

Hydrological responses to land use/cover changes in the source region of the Upper Blue Nile Basin, Ethiopia

Understanding how changes in distinctive land use/land cover (LULC) types influence the basin hydrology would greatly improve the predictability of the hydrological consequences of LULC dynamics for sustainable water resource management. As the main flow contributor to the River Nile, quantifying the effect of LULC change on water resources in the source regions is very important for the assessment of water resources availability and management downstream in the riparian states in general and the study watersheds in particular. In this study, an integrated approach comprising hydrological modeling and partial least squares regression (PLSR) was used to quantify the contributions of changes in individual LULC classes to changes in hydrological components. Two watersheds, namely Lake Tana and Beles in the Upper Blue Nile Basin in Ethiopia, were considered for the conduction of hydrological modeling using LULC maps and the Soil and Water Assessment Tool (SWAT). In the Tana sub-basin, it is found that expansion of cultivation land and decline in woody shrub are the major contributors to the rise in surface run-off and to the decline in the groundwater component. Similarly, decline of woodland and expansion of cultivation land are the major contributors to the increase in surface run-off and water yield in the Beles sub-basin. Increased run-off and reduced baseflow and actual evapotranspiration would have negative impacts on water resources, especially in relation to erosion and sedimentation in the upper Blue Nile River Basin. As a result, expansion of cultivation land and decline in woody shrub/woodland appear to be major environmental stressors affecting local water resources. The wider implications of the hydrological changes on the Easter Nile water resources are briefly discussed. The approach to assessing changes in basin hydrology could generally be applied to a variety of other watersheds for which temporal digital LULC maps are available.

Transdisciplinary research in support of land and water management in China and Southeast Asia: evaluation of four research projects

Transdisciplinary research (TDR) aims at identifying implementable solutions to difficult sustainability problems and at fostering social learning. It requires a well-managed collaboration among multidisciplinary scientists and multisectoral stakeholders. Performing TDR is challenging, particularly for foreign researchers working in countries with different institutional and socio-cultural conditions. There is a need to synthesize and share experience among researchers as well as practitioners regarding how TDR can be conducted under specific contexts. In this paper, we aim to evaluate and synthesize our unique experience in conducting TDR projects in Asia. We applied guiding principles of TDR to conduct a formative evaluation of four consortium projects on sustainable land and water management in China, the Philippines, and Vietnam. In all projects, local political conditions restricted the set of stakeholders that could be involved in the research processes. The set of involved stakeholders was also affected by the fact that stakeholders in most cases only participate if they belong to the personal network of the project leaders. Language barriers hampered effective communication between foreign researchers and stakeholders in all projects and thus knowledge integration. The TDR approach and its specific methods were adapted to respond to the specific cultural, social, and political conditions in the research areas, also with the aim to promote trust and interest of the stakeholders throughout the project. Additionally, various measures were implemented to promote collaboration among disciplinary scientists. Based on lessons learned, we provide specific recommendations for the design and implementation of TDR projects in particular in Asia.

Setting Up Regional Climate Simulations for Southeast Asia

Climate change and climate variability are main drivers for land–use, especially for regions dominated by agriculture. Within the framework of the project Land–Use and Climate Change Interactions in Central Vietnam (LUCCi) regional climate simulations are performed for Southeast Asia in order to estimate future agricultural productivity and to derive adaptive land–use strategies for the future. Focal research area is the Vu Gia-Thu Bon (VGTB) river basin of Central Vietnam. To achieve the goals of this project reliable high resolution climate information for the region is required. Therefore, the regional non-hydrostatic Weather Research and Forecasting (WRF) model is used to dynamically downscale large-scale coupled atmosphere–ocean general circulation model (AOGCM) information. WRF will be driven by the ECHAM5-GCM data and the business-as-usual scenario A1B for the period 1960–2050. The focus of this paper is on the setup of WRF for East Asia. Prior to running the long-term climate simulation in operational mode, experimental simulations using different physical parameterizations have been conducted and analyzed. Different datasets have been used to drive the WRF model and to validate the model results. For the evaluation of the parameterization combination special emphasis is given to the representation of the spatial patterns of rainfall and temperature. In total, around 1.7Mio CPUh are required to perform the climate simulations. The required computing resources have been approved from the Steinbuch Centre for Computing (KIT, SCC).

Integrated River Basin Management in the Vu Gia Thu Bon Basin

The Vu Gia Thu Bon River basin sustains important functions and services, which provide water, food, and energy resources for the people living in the basin as well as for people beyond the basin boundaries. Furthermore, the river basin system provides regulating services like flow attenuation, and various cultural and recreational services. During the last decades, significant infrastructure, like reservoirs, channels, water treatment, and distribution networks, was built to increase the benefits generated from the basin in a reliable and secure way. In order to maintain these functions many institutions are responsible to manage certain sectorial aspects of natural resources, often depending on each other to perform their tasks adequately. During the last decades an intensification of resources uses occurred and the trade offs between different sectors like hydropower, agriculture and urban water has increased—in particular during years or seasons which are characterized by climate extremes like droughts or floods . This situation calls for a more coordinated management approach leading to the collaboration of different sectors throughout the river basin. Providing the right information for decision support is a crucial element of river basin management. In this line, Vu Gia Thu Bon River Basin Information Center (VGTB-RBIC) was established by the research consortium making a reliable scientific database available for all different stakeholders as a first but crucial step toward a coordinated approach to river basin management.

Quantifying bias in hydromorphological monitoring: an evaluation of the German LAWA-OS method

Hydromorphological assessment methods as the on-site assessment of the German Working Group on water issues (LAWA-OS method) provide valuable information for a wide range of water management issues like water body assessment, deficit analysis and planning or monitoring of restoration projects. Considering these demands, the question about the assessment variability of such methods arises. Depending on varying aims, scales and approaches different methods may show contradictory assessment results. The objectives of this work are to quantify assessment deviations between different versions of the LAWA-OS method and to identify the causes of these deviations. The hypothesis is that procedural differences between versions act as deviation factors and lead to scoring discrepancies. A pairwise comparison between assessment results of two representative versions show that the LAWA-OS method is very robust against deviation factors on the overall score level. With increasing differentiation of hydromorphological characteristics on the main parameter and single parameter level, the assessment robustness decreases considerably. Particularly, differing numbers of parameters, differing reference scores and differing score aggregation procedures act as factors for substantial assessment deviations between versions. The work in hand provides scientifically based outputs in relation to the reliability, comparability and applicability of the LAWA-OS assessment results for river ecology issues. In this regard, the work in hand contributes to the quality control of the LAWA-OS method and provides valuable insights for practitioners and policy makers.

Quantifying and evaluating the impacts of cooperation in transboundary river basins on the Water-Energy-Food nexus: The Blue Nile Basin

Efficient utilization of the limited Water, Energy, and Food (WEF) resources in stressed transboundary river basins requires understanding their interlinkages in different transboundary cooperation conditions. The Blue Nile Basin, a transboundary river basin between Ethiopia and Sudan, is used to illustrate the impacts of cooperation between riparian countries on the Water-Energy-Food nexus (WEF nexus). These impacts are quantified and evaluated using a daily model that simulates hydrological processes, irrigation water requirements, and water allocation to hydro-energy generation and irrigation water supply. Satellite-based rainfall data are evaluated and applied as a boundary condition to model the hydrological processes. The model is used to determine changes in the long-term economic gain (i.e. after infrastructure development plans are implemented and in steady operation) for each of Sudan and Ethiopia independently, and for the Blue Nile Basin from WEF in 120 scenarios. Those scenarios result from combinations of three cooperation states: unilateral action, coordination, and collaboration; and infrastructure development settings including the Grand Ethiopian Renaissance Dam and planned irrigation schemes in Sudan. The results show that the economic gain of the Blue Nile Basin from WEF increases with raising the cooperation level between Ethiopia and Sudan to collaboration. However, the economic gain of each riparian country does not necessarily follow the same pattern as the economic gain of the basin.

Land Use and Climate Change Interactions in Central Vietnam

The assessment of land use and climate change interactions requires and produces a lot of different types of data from several disciplines. In order to have a common and web-based platform to manage, share, and present such data in the context of an interdisciplinary international research project, the Vu Gia Thu Bon River Basin Information System (RBIS) was established. The modularly structured information system has a user-friendly interface with full read/write access for the management, linkage, analysis, visualization, and presentation of different types of data in the context of multidisciplinary environmental assessment and planning. Besides the management of metadata, different types of datasets can be managed (e.g., time series data, spatial geodata, documents). Standardized interfaces are provided to enable the exposure and exchange of data with other systems. Here the key features of the system are presented alongside with user related application guidance.

Design and Application of an Adaptive Time Delay Model for Flow Routing in Prismatic Trapezoidal Geometry River Reach

Simplified flow routing model is favourably used for control-based application because it does not only present acceptable results but also is computationally inexpensive. Recently, the Time Delay model (TD) with two parameters, time constant and time delay has been developed in order to approximate the river flow in a very wide rectangular profile. This paper presents an advancement we thereafter call Adaptive Time Delay model (ATD) that expands the application scope of the TD Model by simulating the flow using a prismatic trapezoidal geometry. Firstly, the mathematical representation of the ATD model and the linearized Saint Venant model (SVE) are defined. Secondly, the transfer functions of the ATD model and the complex hydraulic model (SVE) are obtained by Laplace transformation. Finally, the Taylor expansion technique is used to find cumulants of the two transfer functions, and consequently equating the cumulants to derive time constant and time delay of the ATD model as functions of the complex hydraulic model parameters. By applying the fourth order Runge Kutta numerical scheme the flow rate and water level at downstream reach end are simulated. The innovation of this research is that both water stage and flow rate are derived through optimization. The performance of the ATD Model is also presented and compared to the TD Model in a case study. The extension of the time delay model does not only issue more accurate results but also introduces more outcomes like flow rate, and relation curves between time delay and time constant with discharge that might be useful in flood forecasting and other purposes in water resources operation.