QUANTITATIVE EVALUATION OF WATER USE BENEFITS–AN INTEGRATIVE MODELING APPROACH FOR THE GREAT BARRIER REEF REGION

ABSTRACT. . Policy impact assessment is an important task for economic research, especially in the context of water use, where both water quantity and quality issues are crucially linked to human decision making. The resulting impact on water use benefits has many dimensions, representing both market based values with an indication of prices and also non‐market values. This paper aims to develop a model to examine water use benefits within an integrated multi‐disciplinary focus. The integration of market and nonmarket values is implemented in a computable general equilibrium framework. Production functions for nonmarket values are formalized through multi‐criteria analysis. This paper explains how such an integrated approach can be applied using different scenarios for the Great Barrier Reef region in Australia.     

THE ROLE OF JUVENILE DISPERSAL IN THE REPLACEMENT OF GOLDEN‐WINGED WARBLERS BY BLUE‐WINGED WARBLERS

ABSTRACT. In this paper, we test a hypothesis that the replacement of golden‐winged warblers by blue‐winged warblers in the eastern United States is due to the fact that the latter species occupies only a fraction of the habitat of the former species. We build two models, one a simple discrete population model with a one‐year time step, and the second a landscape model that incorporates juvenile dispersal. The second model involves a numerical solution to a linked pair of diffusion equations. The first model shows that eventually the blue‐winged warbler will replace the golden‐winged warbler, but not in the observed 50 year time frame. The second model extends the range of parameter values under which the replacement happens within 50 years, but it still appears that other factors must play a significant role.     

Basin-wide cooperative water resources allocation

The Cooperative Water Allocation Model (CWAM) is designed within a general mathematical programming framework for modeling equitable and efficient water allocation among competing users at the basin level and applied to a large-scale water allocation problem in the South Saskatchewan River Basin located in southern Alberta, Canada. This comprehensive model consists of two main steps: initial water rights allocation and subsequent water and net benefits reallocation. Two mathematical programming approaches, called the priority-based maximal multiperiod network flow (PMMNF) method and the lexicographic minimax water shortage ratios (LMWSR) technique, are developed for use in the first step. Cooperative game theoretic approaches are utilized to investigate how the net benefits can be fairly reallocated to achieve optimal economic reallocation of water resources in the second step. The application of this methodology to the South Saskatchewan River Basin shows that CWAM can be utilized as a tool for promoting the understanding and cooperation of water users to achieve maximum welfare in a river basin and minimize the potential damage caused by water shortages, through water rights allocation, and water and net benefit transfers among water users under a regulated water market or administrative allocation mechanism.     

THE ECONOMICS OF DEFICIT IRRIGATION

Abstract Natural resource economists have paid great attention to irrigation water allocations among competing users. However, the intrauser allocation problem is greatly understudied. As irrigation becomes increasingly capital‐intensive, inefficient within‐field allocation and ill‐designed water‐conservation policy can bring considerable value loss to the water resource. We offer a comprehensive treatment of the economic problem of the intrauser allocation of a limited amount of irrigation water. A framework is provided for determining optimal irrigation intensity and extensity in both static and dynamic settings. An empirical application in West Texas cotton production demonstrates model implementation and offers new insights into the water‐saving potential of government‐sponsored cost‐share programs for promoting high‐efficiency irrigation adoption.     

基于小波去噪和WNN-ARIMA组合模型的年径流预测

为解决单一的小波神经网络预测精度不高的问题,提出一种新的基于小波去噪和WNN-ARIMA组合模型,应用小波阈值去噪法对小波神经网络的输入值进行预处理,同时对模型残差值进行ARIMA模型修正.利用该组合模型对洮河流域下巴沟站年径流量进行预测,预测趋势和预测值与原始实测数据吻合度高,表明此组合模型可靠性强,可以有效预测年径...     

MODELING AND FORECASTING MONTHLY AVERAGE WATER LEVELS BASED ON THE ELLIPTIC ORBIT MODEL

Evaluation and forecasting of water‐level fluctuation for one river is of increasing importance since it is intimately associated with human welfare and socioeconomic sustainability development. In this study, it is found that time series of monthly water‐level fluctuation exhibits annual cyclical variation. Then with annual periodic extension for monthly water‐level fluctuation, the so‐called “elliptic orbit model” is proposed for describing monthly water‐level fluctuation by mapping its time series into the polar coordinates. Experiments and result analysis indicate potentiality of the proposed method that it yields satisfying results in evaluating and forecasting monthly water‐level fluctuation at the monitoring stations in the Yangtze River of China. It is shown that the monthly water‐level fluctuation is well described by the proposed elliptic orbit model, which offers a vivid approach for modeling and forecasting monthly water‐level fluctuation in a concise and intuitive way.     

CLIMATE CHANGE AND COOPERATION IN TRANSBOUNDARY WATER SHARING: AN APPLICATION OF STOCHASTIC STACKELBERG DIFFERENTIAL GAMES IN VOLTA RIVER BASIN

Abstract As multiple countries share a river, the likelihood of conflicts over distributing water resources increases, particularly under the effects of climate change. In this paper, we demonstrate how countries can cooperate in sustainable transboundary water sharing under such conditions. We examine the case of water distribution in the Volta Basin of West Africa between the upstream country, Burkina Faso, and the downstream country, Ghana. The latter faces an additional tradeoff between the production of hydropower in the south, close to the outlet of the basin, and agricultural water use in the reservoir’s catchment area in the north. In the framework of a stochastic Stackelberg differential game, we show how sustainable water‐sharing agreements can be achieved by linking transboundary flows to hydropower exports. Our results indicate that, through cooperation, Ghana will have an opportunity to increase its water abstraction for agriculture, which has remained largely restricted. We also find that the equilibrium strategies for the long‐run distribution are stable even with increasing variances of water flow.     

THE LONG‐RUN INEFFICIENCY OF BLOCK‐RATE PRICING

ABSTRACT. In this paper we compare two regulation instruments, flat‐rate and increasing block‐rate pricing. The analysis applies to a competitive industry with free entry. Charge for irrigation water is a concrete example. It is shown that flat‐rate pricing leads to a first‐best social optimum, while with block‐rate pricing where the highest block set at the marginal cost, there is over production, firms are too small, and loss of economic surplus occurs. Moreover, first‐best is not implementable by increasing block‐rate pricing. This is in contrast to the commonly accepted view that block‐rate pricing is superior to flat‐rate pricing by allowing for income redistribution while preserving efficiency. Several second‐best situations are analyzed to show: 1) Block‐rate pricing with the highest block at the social marginal cost is optimal when the regulator must preserve the number of firms. 2) Water pricing alone cannot implement social optimum subject to a constant level of agricultural production. 3) Lobbying and political pressures, which force the regulator to sustain a constant average water price, result in optimal block‐rate pricing with the highest block below the social marginal cost.     

THE SIZE OF FARSIGHTED STABLE COALITIONS IN A GAME OF POLLUTION ABATEMENT

Abstract The game theoretical analysis of international environmental problems has received increasing attention in recent years. Major issues are as follows. Under which conditions will an international environmental agreement (IEA) be signed? Will the agreement be stable? Game theory has given different answers to these questions; in particular, it is possible to show that if countries are myopic then only small stable coalitions occur, but if they are farsighted then both large and small stable coalitions exist. This paper studies the size of a farsighted stable IEA by considering a quadratic cost function in a pollution abatement model. Following Rubio and Ulph [2006] , we consider both the case of non‐negative emissions as well as the case of unrestricted ones.     

CANADA'S FOREST COVER INDICATOR: DEFINITION,METHODOLOGY AND RESULTS

ABSTRACT. The Environment and Sustainable Development Indicators (ESDI) Initiative was introduced to track Canada's overall wealth in the form of natural and human capital, in additionto familiar economic data such as the gross domestic product (GDP). One of the six ESDIs is the Forest Cover Indicator (FCI). In this paper we define FCI, outline the overall method for deriving FCI, and report results for addressing four key technical issues in carrying out this overall method. The FCI is defined as interannual variations of Canada's forest area with the middle‐summer crown closure (CC) ? 10%. Crown closure is the percentage of the ground surface covered by a downward vertical projection of the tree crowns. Theoverall monitoring method is mainly based on coarse resolution remote sensing data because of the need to cover Canada's extensive landmass during the middle‐summer months and toupdate the results annually. Medium resolution satellite data, field measurements, and modeling approaches were used for calibration, correction, validation, and down‐scaling, with a focus on the following 4 key technical issues: (1) correcting understory non‐tree vegetation effect on CC, (2) downscaling forest cover area from 1‐km to 100‐m spatial resolution as required by the FCI definition, (3) detecting the changes of CC caused by disturbances, and (4) detecting changes in CC caused by forest regrowth. Methods and results for addressing these technical issues are described in the paper. While these results indicate that the key technical issues can be solved by integrating satellite remote sensing data/products and other data, there are clear needs for further development, especially testing against field measurements.     

THE TRANSFORMATION OF LANDSCAPE: MODELING POLICY AND SOCIAL IMPACTS ON THE AGRICULTURAL LANDSCAPE OF LESVOS

ABSTRACT. The term landscape is more and more used as an “umbrella‘ concept, covering a series of cultural, productive and ecological processes. In order to uncover mechanisms, monitor transformations and predict changes, a complicated set of interacting factors has to be taken into account. This paper presents a model for estimating social and policy impacts on agricultural landscapes, based on the assumption that agricultural landscapes are shaped at” macro “(landscape) level by” micro “interventions at farm level. The model consists of three parts: an” ecological processes “part, which deals with processes that shape the ecological and aesthetic value of a landscape, a” population dynamics “part, which examines farmer population dynamics and a” policy impact “part, which deals with direct or indirect impacts on farming systems and farmer dynamics and refers to CAP Rural Development Measures. The model is applied for the olive and graze land agricultural landscapes of Lesvos (Greece). Results, apart from revealing landscape change patterns; help to illustrate some mechanisms behind this change and indicate that Rural Development Measures are inherent with minor but important malfunctions that cannot lead to sustainable landscape management and rural development in the area.     

A fast level set model of multi‐atlas labels fusion for 3D MRI tissues segmentation with application of split Bregman method

In this paper, we propose a new fast level set model of multi‐atlas labels fusion for 3D magnetic resonance imaging (MRI) tissues segmentation. The proposed model is aimed at segmenting regions of interest in MR images, especially the tissues such as the amygdala, the caudate, the hippocampus, the pallidum, the putamen, and the thalamus. We first define a new energy functional by taking full advantage of an image data term, a length term, and a label fusion term. Different from using the region‐scalable fitting image data term and length term directly, we define a new image data term and a new length term, which is also incorporated with an edge detect function. By introducing a spatially weight function into the label fusion term, segmentation sensitivity to warped images can be largely improved. Furthermore, the special structure of the new energy functional ensures the application of the split Bregman method, which is a significant highlight and can improve segmentation efficiency of the proposed model. Because of these promotions, several good characters, such as accuracy, efficiency, and robustness have been exhibited in experimental results. Quantitative and qualitative comparisons with other methods have demonstrated the superior advantages of the proposed model.     

THE USE OF TELESCOPING SPATIAL SCALES TO CAPTURE INSHORE TO SLOPE DYNAMICS IN MARINE ECOSYSTEM MODELING

Abstract Ecosystem processes function at many scales, and capturing these processes is a challenge for ecosystem models. Nevertheless, it is a necessary step for considering many management issues pertaining to shelf and coastal systems. In this paper, we explore one method of modeling large areas with a focus at a range of scales. We develop an ecosystem model that can be used for strategic management decision support by modeling the waters off southeastern Australia using a polygon telescoping approach, which incorporates fine‐scale detail at the coastal zone, increasing in scale to a very coarse scale in the offshore areas. This telescoping technique is a useful tool for incorporating a wide range of habitats at different scales into a single model.     

On resonant interactions of gravity‐capillary waves without energy exchange

We consider resonant triad interactions of gravity‐capillary waves and investigate in detail special resonant triads that exchange no energy during their interactions so that the wave amplitudes remain constant in time. After writing the resonance conditions in terms of two parameters (or two angles of wave propagation), we first identify a region in the two‐dimensional parameter space, where resonant triads can be always found, and then describe the variations of resonant wavenumbers and wave frequencies over the resonance region. Using the amplitude equations recovered from a Hamiltonian formulation for water waves, it is shown that any resonant triad inside the resonance region can interact without energy exchange if the initial wave amplitudes and relative phase satisfy the two conditions for fixed point solutions of the amplitude equations. Furthermore, it is shown that the symmetric resonant triad exchanging no energy forms a transversely modulated traveling wave field, which can be considered a two‐dimensional generalization of Wilton ripples.     

INDIVIDUAL‐BASED MODELS AND THE MANAGEMENT OF SHOREBIRD POPULATIONS

Abstract Individual‐based models (IBMs) predict how animal populations will be affected by changes in their environment by modeling the responses of fitness‐maximizing individuals to environmental change and by calculating how their aggregate responses change the average fitness of individuals and thus the demographic rates, and therefore size of the population. This paper describes how the need to develop a new approach to make such predictions was identified in the mid‐1970s following work done to predict the effect of building a freshwater reservoir on part of the intertidal feeding areas of the shorebirds Charadrii that overwinter on the Wash, a large embayment on the east coast of England. The paper describes how the approach was developed and tested over 20 years (1976–1995) on a population of European oystercatchers Haematopus ostralegus eating mussels Mytilus edulis on the Exe estuary in Devon, England. The paper goes on to describe how individual‐based modeling has been applied over the last 10 years to a wide range of environmental issues and to many species of shorebirds and wildfowl in a number of European countries. Although it took 20 years to develop the approach for 1 bird species on 1 estuary, ways have been found by which it can now be applied quite rapidly to a wide range of species, at spatial scales ranging from 1 estuary to the whole continent of Europe. This can now be done within the time period typically allotted to environmental impact assessments involving coastal bird populations in Europe. The models are being used routinely to predict the impact on the fitness of coastal shorebirds and wildfowl of habitat loss from (i) development, such as building a port over intertidal flats; (ii) disturbance from people, raptors, and aircraft; (iii) harvesting shellfish; and (iv) climate change and any associated rise in sea level. The model has also been used to evaluate the probable effectiveness of mitigation measures aimed at ameliorating the impact of such environmental changes on the birds. The first steps are now being taken to extend the approach to diving sea ducks and farmland birds during the nonbreeding season. The models have been successful in predicting the observed behavior and mortality rates in winter of shorebirds on a number of European estuaries, and some of the most important of these tests are described. These successful tests of model predictions raise confidence that the model can be used to advise policy makers concerned with the management of the coast and its important bird populations.     

A COALITION APPROACH TO THE MANAGEMENT OF HIGH SEAS FISHERIES IN THE PRESENCE OF EXTERNALITIES

ABSTRACT. The current paper extends the coalition approach of the management of high seas fisheries to the presence of externalities. The coalition approach is set within the framework of a two‐stage game in which the payoffs depend on the entire coalition structure and are determined through a partition function. The relationship between the presence of externalities and the stability of the coalition structures is explored. The equilibrium coalition structures of the game are also examined. The application of the game to the Northern Atlantic bluefin tuna shows a typical picture of the high seas fisheries: the simultaneous presence of strong externalities in the coalition structures and the absence of stability of the grand coalition. A fundamental conclusion of this paper is that, generally, in order to guarantee the stability of the cooperative agreements it is not sufficient to implement a fair sharing rule for the distribution of the returns from cooperation. Stability requires a legal regime preventing the players that engage in noncooperative behavior from having access to the resource.     

平面点列的自动光顺算法

本文考虑平面点列的光顺问题并将该问题化成最小能量曲线的构成问题，即在原点列和相应允许误差构成的带状区域内构造一条最小能量曲线并给出一种自动算法．整个光顺过程分成两步，第一步利用凸分析原理在原点列的允许变动范围内除去多余拐点；第二步在保凸的前提下构造插值点列的最小能量曲线并通过对最小能量曲线进行修正而达到对原型值点列进行光顺的目的．光顺结果不仅可以得到一光顺点列，同时还得到了一条插值点列的光顺曲线．该方法可以对分布不均匀甚至有较大转角的点列进行光顺，与已有的方法比起来具有光顺能力强光顺范围广的特点．     

加权有理三次插值的逼近性质及其应用

利用带导数和不带导数的分母为线性的有理三次插值样条构造了一类加权有理三次插值函数,利用这种插值方法,将样条曲线严格约束于给定的折线之上、之下或之间的问题都可以得到解决同时还研究了这种加权有理三次插值的逼近性质。     

素数变数的线性方程组

<正> 引言 在苹雁庚教授的著作“堆曼素数箫”第十二章中曹握提出了阴龄整保数素数燮数的腺性方程粗的解的问题.这个问题是有名的(?)定理的自然推广.1937年苏联(?)院士首先证明了任何充分大的奇整数 N 都能表成三个素数之和,且如令 I(N) 为表示法的种数,则     

CLEANING A RIVER: AN ANALYSIS OF VOLUNTARY JOINT ACTION

Abstract River pollution creates negative externalities to downstream water users. In this paper, we analyze how voluntary joint action of water users can improve pollution abatement when optimal treatment cannot be enforced. We model a transboundary pollution game with a unidirectional pollutant flow. Players are identical except for their location along the river. We find that, surprisingly, the location of coalition members has no impact on coalition stability. Location does, however, affect overall welfare. The more upstream the members of the coalition are, the higher is the overall welfare because the positive externalities of cleaning accrue to a larger number of downstream water users.