Dynamic parallelization of hydrological model simulations

This paper introduces the development of a dynamic parallel algorithm for conducting hydrological model simulations. This new algorithm consists of a river network decomposition method and an enhanced master-slave paradigm. The decomposition method is used to divide a basin river network into a large number of subbasins, and the enhanced master-slave paradigm is adopted to realize the function of this new dynamic basin decomposition method through using the Message-Passing Interface (MPI) and C++ language. This new algorithm aims to balance computation load and then to achieve a higher speedup and efficiency of parallel computing in hydrological simulation for the river basins which are delineated by high-resolution drainage networks. This paper uses a modified binary-tree codification method developed by Li etal. (2010) to code drainage networks, and the basin width function to estimate the possible maximum parallel speedup and the associated efficiency. As a case study, with a hydrological model, the Digital Yellow River Model, this new dynamic parallel algorithm is applied to the Chabagou basin in northern China. The application results reveal that the new algorithm is efficient in the dynamic dispatching of simulation tasks to computing processes, and that the parallel speedup and efficiency are comparable with the estimations made by using the basin width function. © 2011 Elsevier Ltd.postprin

Double-layer parallelization for hydrological model calibration on HPC systems

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Automatic drainage pattern recognition in river networks

In both geographic information system and terrain analysis, drainage systems are important components. Owing to local topography and subsurface geology, a drainage system achieves a particular drainage pattern based on the form and texture of its network of stream channels and tributaries. Although research has been done on the description of drainage patterns in geography and hydrology, automatic drainage pattern recognition in river networks is not well developed. This article introduces a new method for automatic classification of drainage systems in different patterns. The method applies to river networks, and the terrain model is not required in the process. A series of geometric indicators describing each pattern are introduced. Network classification is based on fuzzy set theory. For each pattern, the level of membership of the network is given by the different indicator values. The method was implemented, and the experimental results are presented and discussed

Technology, Science, and Culture: A Global Vision

The aim of the Workshop: Technology, Science, and Culture - A Global Vision is to create a discussion forum on research related to the fields of Water Science, Food Science, Intelligent Systems, Molecular Biomedicine, and Creation and Theories of Culture. The workshop is intended to discuss research on current problems, relevant methodologies, and future research streams and to create an environment for the exchange of ideas and collaboration among participants

A continental landscape framework for systematic conservation planning for Australian rivers and streams

Conservation of Australia’s distinctive river ecosystems has lagged behind that of terrestrial and marine environments despite mounting evidence of the destructive effects of human activities. There has been little nationally coordinated conservation activity. A systematic, continent-wide conservation planning approach would ensure limited conservation resources are allocated efficiently and decisions are accountable. This thesis addresses critical gaps in the spatial data required for systematic conservation planning. It describes the development of a stream network and nested catchment reference system to provide the spatial framework. This framework, at a map scale of approximately 1:250,000, supplies planning units for application of reserve design algorithms and determination of priorities for protective management as well as units for reporting conservation evaluation and assessment. The Pfafstetter coding of the catchment units identifies drainage network connectivities allowing them to be readily incorporated into conservation planning procedures. This thesis presents for the first time a comprehensive picture of continent-wide variation in the landscape factors that ultimately control riverine ecosystem patterns and processes. Stream segments, the section of the stream between tributary confluences and the smallest unit in the spatial framework, have been individually characterized and classified at multiple scales using attributes that describe the catchment (and/or sub-catchment) climate, water balance, geology, terrain and vegetation. Segments were clustered according to their similarity in environmental data space so that, unlike ecoregion classifications, groups may be geographically dispersed. The resulting River Environment Types have been found to differentiate significant variation in stream biota (macroinvertebrates and fish) and habitat characteristics. However, classification strength varies widely among types. It is hypothesised that this is due to both classification uncertainty and limitations of the test data. The spatial framework and classifications are the central elements of a continental landscape framework that could be used to support systematic conservation planning and assist the development of a national conservation plan for Australia’s rivers and streams. The framework could also provide the basis for an online information system to serve a broader range of NRM planning and management objectives. The utility of the continental framework has been demonstrated in a review of the National Reserve System (NRS). The review acknowledges some uncertainty in the results due to inaccuracies and limitations of the framework, but nevertheless, concludes that the NRS must be expanded if it is to achieve a comprehensive and adequate protected area system for river ecosystems. This study makes major contributions to spatial analysis methodology. It has developed and applied a new method of drainage analysis applicable to diverse drainage structures at continental scale and recommends enhancements to the internationally adopted Pfafstetter scheme. It also advances understanding of the role for landscape classification and the influence of classification choice on conservation planning outcomes. The development of the continental landscape framework for Australia presents a model and the necessary tools for conservation planning for the rivers and streams of other continents

Investigating soil change in Edgeroi, New South Wales using pedogenon mapping framework

The impact of anthropogenic activities on soil has been significant in the last few hundred years, surpassing that of natural processes that occurred over thousands of years. Soil organic carbon (SOC) is especially vulnerable to anthropogenic forces and is critical to support soil functions such as nutrient and water cycling, crop production, and habitat for ground biodiversity. It is hence crucial to understand the current SOC status and predict how it has changed due to human influences. However, assessing changes in soil is challenging due to the various factors involved in soil formation. This thesis studies the SOC change in the Edgeroi area of New South Wales since European settlement using the pedogenon mapping concept. Pedogenon divides a landscape into unique soil entities based on homogeneous soil-forming factors, distinguishing soils that have been less affected by human activities (genosoil) and those that have been intensely affected (phenosoils). The primary hypothesis of this thesis is that pedogenon mapping can effectively stratify the landscape and be used to estimate soil change. To produce pedogenon classes, a parent material map of the study area was produced using interpretation and machine-learning methods. An unsupervised classification of spatial layers representing soil-forming factors was then used to create the pedogenon map. Within each pedogenon, genosoil and phenosoil areas were identified using land use data. Multivariate data analysis confirmed each pedogenon has unique soil properties from the surface down to 1 m. SOC data from genosoil and phenosoil areas were then compared and mapped to investigate soil change. The results showed the soil property variation under phenosoil is half that of genosoil due to agricultural practices. Additionally, this approach enables the mapping of SOC sequestration potential using mineral-associated OC contents. This thesis improves the current digital soil mapping approach for assessing soil change

Metadata-catalogue of European spatial datasets

In order to facilitate a more effective accessibility of European spatial datasets, an assessment was carried out by the GeoDesk of the WUR to identify and describe key datasets that will be relevant for research carried out within WUR and MNP. The outline of the Metadata catalogue European spatial datasets, the classification of the datasets and the use of specific standards, is based on the work which was be done by the INSPIRE (INfrastructure for SPatial InfoRmation in Europe) initiative. The objective of the report is that it can speed up the process for identification of suitable datasets during the following steps: - to inform on the existence of European spatial datasets that could be relevant for a specific project; - to evaluate if a dataset will be suitable by exploring the metadata; - to indicate if a relevant spatial dataset is available and give directions how it can be obtaine

Analyse temporelle et spatiale des composantes chimiques, hydromorphologiques et diatomiques en relation avec les changements globaux

L'objectif de cette thèse était d'évaluer l'effet des changements globaux sur les milieux aquatiques. L'analyse exploratoire des bases de données d'occupation des sols, de physico-chimie, d'hydromorphologie, de diatomées dans les cours d'eau du bassin Adour-Garonne et de diatomées en Guyane a mis en évidence : 1) l'effet du changement global sur la qualité des eaux marquée par la hausse des températures et une atténuation sensible de l'eutrophisation ; 2) l'importance prépondérante des patrons d'occupation des sols à l'échelle du bassin versant ; 3) la persistance des diatomées et le changement des caractéristiques des communautés périphytiques face aux conditions de stress extrême dues à l'orpaillage en Guyane. Ces résultats ont démontré leurs valeurs quant à leurs potentiels de transfert vers les domaines de "la recherche appliquée" en proposant : 1) un référentiel temporel de la qualité chimique des eaux du bassin Adour-Garonne ; 2) l'intégration des patrons de l'occupation des sols à l'échelle du bassin versant dans le développement de nouveaux outils de bio-indication ; 3) la mise au point d'un indice diatomique générique basé sur les capacités motrices des diatomées et destiné au contexte guyanais.This thesis aimed at assessing the effect of global changes on aquatic ecosystems. The exploratory analysis of the land cover patterns, physicochemical, hydromorphological, and diatom databases in the Adour-Garonne basin and the diatom flora of streams in French Guyana highlighted: 1) the effect of the global changes on the water quality characterized by the temperature increase and the significant mitigation of eutrophication ; 2) the strongest influence of the land cover patterns at the catchment scale ; 3) the persistence of the diatom flora and the change of community structures facing extreme stress due to gold mining ; These results testified their importance as for their potential transfers towards the fields of "applied research", particularly proposing: 1) a temporal reference frame of the chemical water quality of the Adour-Garonne basin ; 2) to integrate the land cover patterns extracted at the catchment scale in order to improve or develop new biomonitoring tools ; 3) the development of a new generic diatom index appropriate to the French Guyana context based on the diatom motility abilities

Advances in Data Mining Knowledge Discovery and Applications

Advances in Data Mining Knowledge Discovery and Applications aims to help data miners, researchers, scholars, and PhD students who wish to apply data mining techniques. The primary contribution of this book is highlighting frontier fields and implementations of the knowledge discovery and data mining. It seems to be same things are repeated again. But in general, same approach and techniques may help us in different fields and expertise areas. This book presents knowledge discovery and data mining applications in two different sections. As known that, data mining covers areas of statistics, machine learning, data management and databases, pattern recognition, artificial intelligence, and other areas. In this book, most of the areas are covered with different data mining applications. The eighteen chapters have been classified in two parts: Knowledge Discovery and Data Mining Applications