Set-up of a decision support system to support sustainable development of the Laguna de Bay,Philippines

Over recent decades, population expansion, deforestation, land conversion, urbanisation, intense fisheries and industrialisation have produced massive changes in the Laguna de Bay catchment, Philippines. The resulting problems include rapid siltation of the lake, eutrophication, inputs of toxics, flooding problems and loss of biodiversity. Rational and systematic resolution of conflicting water use and water allocation interests is now urgently needed in order to ensure sustainable use of the water resources. With respect to the competing and conflicting pressures on the water resources, the Laguna Lake Development Authority (LLDA) needs to achieve comprehensive management and development of the area. In view of these problems and needs, the Government of the Netherlands was funding a two-year project entitled 'Sustainable Development of the Laguna de Bay Environment'.A comprehensive tool has been developed to support decision-making at catchment level. This consists of an ArcView GIS-database linked to a state-of-the-art modelling suite, including hydrological and waste load models for the catchment area and a three-dimensional hydrodynamic and water quality model (Delft3D) linked to a habitat evaluation module for the lake. In addition, MS Office based tools to support a stakeholder analysis and financial and economic assessments have been developed. The project also focused on technical studies relating to dredging, drinking water supply and infrastructure works. These aimed to produce technically and economically feasible solutions to water quantity and quality problems. The paper also presents the findings of a study on the development of polder islands in the Laguna de Bay, addressing the water quantity and quality problems and focusing on the application of the decision support system.     

城市地震应急对策支持系统研究

从地震灾害学理论和地震应急工作需求出发,讨论了应急工作的内容和层次,提出了应急目标和应急资源的定义;并对城市地震应急对策支持系统的总体设计、功能模块、数据库、模型库以及系统的实现方法等方面进行了探讨。     

地震应急对策决策支持软件的设计与开发

基于空间决策支持技术,设计与开发了地震应急对策软件,在软件的总体设计、功能模块、数据库建设、地震应急对策模型及接口设计与模块集成等方面进行了研究与开发,并在“青岛市地震应急指挥决策支持软件系统”中得到实际应用和检验。实践证明,该软件能够实现城市地震灾害信息的科学管理,智能制定各种地震应急对策和生动的可视化,从而有效提高地震应急的效率和响应速度,为城市地震应急工作提供了有效的辅助决策手段;建成的“青岛市地震应急对策系统”对全国大中城市地震应急指挥技术系统的建设具有示范意义。     

The Self Diagnosis Method. A new methodology to assess environmental management in sea ports

A methodology has been designed to assess the performance of the environmental management in sea ports. The Self Diagnosis Method, developed by two research teams and about sixty sea ports, allows the comparison of the current environmental situation with that corresponding to previous years and the assessment of the opportunities for improvement. The main objective is to review the management activities and procedures that affect the environment and the way the port authority handles significant environmental aspects. It has been designed as a "first level" tool: it can be applied in approximately six hours by a non-expert user. It is based on the ISO 14001 vocabulary, requirements and structure, and it can be considered as a first step in the voluntary implementation of an environmental management system for port communities.     

A relocatable ocean model in support of environmental emergencies

During the Costa Concordia emergency case, regional, subregional, and relocatable ocean models have been used together with the oil spill model, MEDSLIK-II, to provide ocean currents forecasts, possible oil spill scenarios, and drifters trajectories simulations. The models results together with the evaluation of their performances are presented in this paper. In particular, we focused this work on the implementation of the Interactive Relocatable Nested Ocean Model (IRENOM), based on the Harvard Ocean Prediction System (HOPS), for the Costa Concordia emergency and on its validation using drifters released in the area of the accident. It is shown that thanks to the capability of improving easily and quickly its configuration, the IRENOM results are of greater accuracy than the results achieved using regional or subregional model products. The model topography, and to the initialization procedures, and the horizontal resolution are the key model settings to be configured. Furthermore, the IRENOM currents and the MEDSLIK-II simulated trajectories showed to be sensitive to the spatial resolution of the meteorological fields used, providing higher prediction skills with higher resolution wind forcing.     

Hydraulic characteristics and habitat suitability in presence of woody debris: A flume experiment

Data from a flume experiment were used to explore the modified hydraulic conditions and habitat suitability in streams where feeding of large woody debris (LWD) is present. Feeding of LWD was simulated by insertion of wood dowels with varying diameter and length. Two processes were mimicked, namely (i) lumped LWD load, and (ii) distributed LWD load. Lumped load may occur for wood coming either from upstream or from a tributary, and entering the stream of interest in one only section. Distributed load occurs for wood entering along the considered stream, in several sections. Distributed wood income resulted in homogeneously increased bed roughness, leading to increased flow depth and decreased velocity, whereas lumped input of wood from upstream resulted in larger local clustering and change of the flow properties, but with less influence on the distributed hydraulic properties. A method is proposed to predict bulk flow properties in presence of LWD. Then, a simple approach is used based upon the concept of wetter usable area WUA to investigate modified habitat conditions for fish species in presence of woody debris. An application to a real world case study from the literature is then shown, where increasing density of wood increases habitat availability for colonization by fish guilds.     

Tasks and functions of a decision support system for water resources management in the Lower Volga

The Lower Volga is a Russian region, which has a unique natural resources and a territory which is the area of collision of the interests of different economic branches that use water resources. The economic development of the region requires effective water resources management in harmony with natural conditions and the operation of the Volga-Kama reservoir system. A reliable management tool is a computer decision support system for the Lower Volga. The problems to be solved with this system answer the current water problems of the region. Data on the programs under implementation and to be developed are given; water apportioning model is given; and the way of coordinated choice of management regime of the Volga-Kama reservoir system and water resources use in the Lower Volga is demonstrated.     

Sensitivity of acoustic propagation to uncertainties in the marine environment as characterized by various rapid environmental assessment methods

Accurate sonar performance prediction modelling depends on a good knowledge of the local environment, including bathymetry, oceanography and seabed properties. The function of rapid environmental assessment (REA) is to obtain relevant environmental data in a tactically relevant time frame, with REA methods categorized by the nature and immediacy of their application, from historical databases through remotely sensed data to in situ acquisition. However, each REA approach is subject to its own set of uncertainties, which are in turn transferred to uncertainty in sonar performance prediction. An approach to quantify and manage this uncertainty has been developed through the definition of sensitivity metrics and Monte Carlo simulations of acoustic propagation using multiple realizations of the marine environment. This approach can be simplified by using a linearized two-point sensitivity measure based on the statistics of the environmental parameters used by acoustic propagation models. The statistical properties of the environmental parameters may be obtained from compilations of historical data, forecast conditions or in situ measurements. During a field trial off the coast of Nova Scotia, a set of environmental data, including oceanographic and geoacoustic parameters, were collected together with acoustic transmission loss data. At the same time, several numerical models to forecast the oceanographic conditions were run for the area, including 5- and 1-day forecasts as well as nowcasts. Data from the model runs are compared to each other and to in situ environmental sampling, and estimates of the environmental uncertainties are calculated. The forecast and in situ data are used with historical geoacoustic databases and geoacoustic parameters collected using REA techniques, respectively, to perform acoustic transmission loss predictions, which are then compared to measured transmission loss. The progression of uncertainties in the marine environment, within and between different REA categories, and the consequences on acoustic propagation are examined.     

Mapping the environmental risk of a tourist harbor in order to foster environmental security: Objective vs. subjective assessments

A new definition of environmental security gives equal importance to the objective and subjective assessments of environmental risk. In this framework, the management of tourist harbors has to take into account managers’ perceptions. The subject of the present study is a tourist harbor in southern Italy where six different managers are present. This paper aims to assess subjectively and objectively the environmental risks associated with the harbor, and to compare the results to provide estimates of environmental security. Hereby managers have been interviewed and a simple model is used for making preliminary assessment of environmental risks. The comparison of the results highlighted a common mismatch between risk perception and risk assessment. We demonstrated that the old part of the harbor is less secure than the new part. In addition, one specific manager representing a public authority showed a leading role in ensuring the environmental security of the whole harbor.     

The use of environmental integrative indicators to assess seabed disturbance in estuaries and coasts: Application to the Humber Estuary, UK

The coastal zone is subject to many and varied changes resulting from human activities and natural processes. Existing or emerging agreements and legislation acknowledge the relevance of indicators for monitoring these. In the UK, following a series of recent workshops, potential indicators of nearshore disturbance have been identified and grouped into three broad indices: 'Coastline Morphological Change', 'Resource Use Change' and 'Environmental Quality and its Perception'. The present study developed these indicators further and tested their use by applying them to 18 sections in the Humber Estuary, Eastern England. The results obtained reflect the current knowledge of the state of the Humber environment and show the potential of integrative indicators but indicate that further studies are required to assess the relative importance of the indicators and their value in reflecting the ability of the ecosystems to sustain natural habitats and populations at a good conservation status.     

Classification of natural flow regimes in Iran to support environmental flow management

Abstract

Development of environmental flow standards at the regional scale has been proposed as a means to manage the influence of hydrological alterations on riverine ecosystems in view of the rapid pace of global water resources management. Flow regime classification forms a critical part in such environmental flow assessments. We present a national-scale classification of hydrological regimes for Iran based on a set of hydrological metrics. It describes ecologically relevant characteristics of the natural hydrological regime derived from 15- to 47-year-long records of daily mean discharge data for 539 streamgauges within a 47-year period. The classification was undertaken using a fuzzy partitional method within Bayesian mixture modelling. The analysis resulted in 12 classes of distinctive flow regime types that differ in various hydrological aspects. This classification is being used for further research in regional-scale environmental flow studies in Iran.

Editor D. Koutsoyiannis     

Stochastic evolution of hydraulic geometry relations in the lower Yellow River of China under environmental uncertainties

Hydraulic geometry relations comprise a classic way to understand characteristics of a river. However, environmental changes pose large uncertainties for the reliability of such relations. In the current study, on the basis of the ordinary differential equations (ODEs) formed through linear treatment of the deterministic power-law hydraulic geometry relations, a set of stochastic differential equations (SDEs) driven by Fractional white noise and Poisson noise are developed to simulate the historical dynamic probability distributions of typical hydraulic geometry variables such as slope, width, depth, and velocity with bankfull discharge variation over time in the lower Yellow River of China. One group of possible stochastic average behaviors within the next 50 years are calculated under three different design incoming water-sediment conditions (including 300, 600, and 800 million t of annual average sediment discharge). In each part of the lower reaches, after estimation of the SDE parameters using a nonparametric maximum likelihood estimation (MLE) method, the model is carefully examined using Monte Carlo simulation as compared with the deterministic control models. The results of this comparison reveal the potential responses of hydraulic geometry characteristics to environmental disturbances, and the average trends mainly agree with the measurements. Comparisons among the three different prediction results reveal the stochastic average solution generally is greater than the deterministic solution. The results also confirm the severe negative impacts that result from the condition of 300 million t of incoming sediment, thus, pointing out the need to raise the level of river evolution alert for the lower Yellow River of China in the future. Moreover, with the help of the stochastic computation, the stream power and hydraulic width/depth ratio could be representative of an effective systematic measure for river dynamics. The proposed stochastic approach is not only important to development in the field of fluvial relations, but also beneficial to the practical design and monitoring of a river system according to specified accuracy requirements.     

A methodology to assess the delivery of road runoff in forestry environments

This paper outlines a conceptual and methodological approach to evaluating the risk of road derived runoff delivery, which is based on the principle of hydrological connectivity. Three different types of runoff delivery pathways are identified (stream crossings, gullied pathways and diffuse pathways) and the volume of runoff that may reach the stream through these pathways during a one in 10 year 30 minute event is estimated. The methodology is applied to three catchments of contrasting forest use, both plantation and native. Results show that degree of connectivity of a road depends on catchment characteristics such as the topography, road placement, drain spacing and road and drainage density. Maps outlining the distribution of different delivery pathways within a catchment are used to assess the potential for runoff connectivity. In one of the selected study catchments, the Albert River, greatest potential connectivity can be isolated to a single road. The upper part of this road crosses many tributaries resulting in high connectivity via stream crossings, whereas the lower part of the road is located within the valley bottom, where the majority of drains will contribute runoff during a one in 10 year event through diffuse overland flow. The presented methodology is also used to highlight hot‐spots in terms of runoff and sediment delivery through the creation of risk assessment maps, which allows for the evaluation of different procedures for road rehabilitation. Using examples from the Albert River catchment, we demonstrate that minimizing diffuse overland flow can generally be achieved by the placement of additional road drains, whereas at highly connected road segments the relocation of the road might be the only option. Copyright © 2007 John Wiley & Sons, Ltd.     

基于GIS的大中城市应急决策反应系统设计与实现

大中城市应急决策反应系统采用了B/S与C/S相结合的框架结构,它集GIS与.NET最新技术为一体,为地震应急指挥开发构建了一个综合业务技术平台。本文介绍城市应急决策反应系统的设计思路、技术关键点及其应用等,该技术系统实现了各地与上级各指挥中心之间便捷的灾情上报,能够为地震应急指挥快速、动态提供灾情文档和辅助决策。     

An evaluation of uncertainties in monitoring middle atmosphere temperatures with the ground-based lidar network in support of space observations

The capability of the longest lidar data sets to monitor long-term temperature changes have been evaluated through comparisons with the successive Stratospheric Sounder Units (SSU) onboard NOAA satellites. Cross-consistency investigations between SSU and the lidar network can be considered as a first attempt to demonstrate how the synergistic use of space and ground-based instruments could provide reliable monitoring of the temperature of the middle atmosphere. The breakdown of the temperature cooling trend, and the following flattening observed in the satellite temperature series, is qualitatively confirmed by the lidars. However, there are still large differences that can either be due to SSU continuity (orbit drifts or weighting function modifications) or lidar operation changes (time of measurements, accuracy, sampling, etc.). SSU vertical weighting functions have been taken into account for comparisons. Some discontinuity events cannot be explained by the SSU weighting function drifts due to CO₂. For the upper channels of SSU (peaking around 50 km), the results are probably sensitive to the mesospheric part of the lidar profiles that can explain some discontinuities. Tropical lidar stations show clear inter-annual differences with the SSU channels covering the lowest altitude range that needs further investigations to understand if the origin is instrumental or geophysical. An attempt to derive non-linear trends with combinations of linear, hockey stick, and quadratic functions has been made. While the quadratic term is not highly significant, this approach allows the derivation of a better quantification of the linear trend terms.     

A study of parameter uncertainties causing uncertainties in modeling a grassland ecosystem using the conditional nonlinear optimal perturbation method

In this paper, we apply the approach of conditional nonlinear optimal perturbation related to the parameter (CNOP-P) to study parameter uncertainties that lead to the stability (maintenance or degradation) of a grassland ecosystem. The maintenance of the grassland ecosystem refers to the unchanged or increased quantity of living biomass and wilted biomass in the ecosystem, and the degradation of the grassland ecosystem refers to the reduction in the quantity of living biomass and wilted biomass or its transformation into a desert ecosystem. Based on a theoretical five-variable grassland ecosystem model, 32 physical model parameters are selected for numerical experiments. Two types of parameter uncertainties could be obtained. The first type of parameter uncertainty is the linear combination of each parameter uncertainty that is computed using the CNOP-P method. The second type is the parameter uncertainty from multi-parameter optimization using the CNOP-P method. The results show that for the 32 model parameters, at a given optimization time and with greater parameter uncertainty, the patterns of the two types of parameter uncertainties are different. The different patterns represent physical processes of soil wetness. This implies that the variations in soil wetness (surface layer and root zone) are the primary reasons for uncertainty in the maintenance or degradation of grassland ecosystems, especially for the soil moisture of the surface layer. The above results show that the CNOP-P method is a useful tool for discussing the abovementioned problems.