The Out-of-Kilter Algorithm and Some of its Applications in Water Resources

The purpose of this paper is to present a simple water resources allocation model based on the Fulkerson's out-of-kilter algorithm. This algorithm is a special purpose linear programming method which has been efficiently used for the solution of a number of water resources problems, just to mention the Texas Water Plan in the USA, the Vistula River Project in Poland, and the Trent River System in Canada. The model is presented in form of a complete computer program OKAY written in the Fortran language. Potential applications of the model are illustrated by few computational examples. Although in principle this is an allocation model for a single time period, the possibilities of its extension to multiperiod analysis are also briefly discussed. The model presented herein is of a general nature and can be considered as a base for development of more complex computer programs designed according to the specific character of a problem subject to analysis. Its original feature is iterative use of the out-of-kilter algorithm to take care of the so-called consumptive losses which as a rule occur in all water resources systems

Temperature Effects on Development of Three Cereal Aphid Parasitoids (Hymenoptera: Aphidiidae)

Temperature is an important climatological variable that influences the biology and ecology of insects. Poor climatic adaptation can limit the effectiveness of parasitic insects in biological control. Two exotic parasites (Syrian Diaeretiella rapae (M\u27Intosh) and Argentinean Aphidius colemani Viereck) imported for biological control of the Russian wheat aphid, Diuraphis noxia (Mordvilko), and one native parasite (Diaeretiella rapae) were reared in growth chambers in three fluctuating temperature regimes with average daily temperatures of 12, 18, and 24°C. Estimates of temperature thresholds for immature development were 3.3, 3.5, and 2.8°C, for Oklahoman D. rapae, Syrian D. rapae, and A. colemani, respectively. Estimates of thermal require- ments for development from egg to adult were 297, 278, and 301 degree-days for the three parasitoids. Dry weights of adults reared in different fluctuating temperature regimes did not differ significantly among sexes, but adults from regimes with low average temperatures of 12 and 18°C had significantly greater weights than those reared in a regime with an average temperature of 24°C. Results suggest that developmental response to temperature will not limit the effectiveness of the exotic parasites in biological control

The Operation of Multiple Reservoir Systems

The purpose of this workshop was to discuss, compare and evaluate various methods of operating, and determining operating policies for multi-purpose, multiple reservoir systems. While total reservoir capacities are known, the allocation of various storage volume zones within the reservoirs to various purposes, such as water supply or flood control, may vary in time and be dependent on reservoir operating policy. In the guidelines for preparation of the papers included in this volume, it was stressed that discussion should cover reservoir operation for all possible hydrological situations, i.e., in periods of flood, normal flow, and drought conditions. The importance of procedures used to determine when an extreme situation (such as drought), begins and ends, was emphasized, especially with respect to possible changes in reservoir operation. The participants were requested to discuss how operating policies might differ, depending on whether the reservoirs are in series or are parallel. Also, they were requested to distinguish between operation of "large" over-year storage reservoirs and "small" within-year storage reservoirs. If short-term hydrological forecasting and real-time control models were to be used, the workshop discussion would consider how these could be used together with long-term operating policies. Some 30 participants from 13 countries presented 17 papers at the workshop, all of which are included in these proceedings. The first nine provide an overview of how multiple reservoir systems are operated in certain countries. The remaining papers report in more detail on diverse case studies and provide discussion of some specific issues related to the subject of the workshop

Integrated Water Demand/Supply Management in Southwestern Skane: A Preliminary Analysis

The water management system in South-Western Skane features different water supply sources (surface and groundwater), municipal water demand zones, and several agricultural water users. In the future the Bolmen Lake scheme will be made operational. The major question now is what are the advantages and disadvantages of integrating all sub-regional solutions into a regional water resources system (particularly in terms of increased reliability). River Basins are the main feature of the sub-regional water resource systems in South Western Skane. A simulation model, MITSIM-2, was developed to analyze the hydrologic performance of these systems. Using this model and water use projections based upon projections of the future demo-economic structure of South Western Skane, a preliminary analysis of a regionally integrated water supply system was performed. This analysis examined the ability of the regionally integrated system to satisfy the water requirements of South Western Skane under different development scenarios

On Some Multi-Site Multi-Season Streamflow Generation Models

The relative performance of some multi-site multi-season models is compared with respect to their adequacy for simulating monthly streamflow sequences. The three models brought under examination are the extended version of the multi-variate model proposed by Matalas (1967), the model formulated by Young and Pisano (1968), and the disaggregation model of Valencia and Schaake (1972). Computer implementation of these models has been accomplished in the form of the Multi-site Multi-season Streamflow Generation Package (MMSGP). Evaluation and comparison of the models has been carried out in terms of statistical flow parameters only. Some of these parameters are not explicitly built into the model structure. At the end, some general comments concerning applicability of each model are presented. [Since this phase of investigations was completed, Mejia and Roussele (1976) have proposed modification of the disaggregation model which will be taken into account in the further work on the MMSGP.

Lublin-Vistula Case Study

Making optimum use of the water resources is a task which long has engaged human effort and which has, in recent decades, been studied within the framework of the integrated regional development plans. The "integrated development" of a region means the orderly marshalling of all its resources to promote human welfare. It is evident, however, that the influence of development of a given region upon the rest of the national economy is in most of the cases considerable. Moreover, the investment needs of any development scheme are closely linked to the needs of the whole economy. These introductory comments are especially relevant to the water resources development schemes. It is now widely recognized that individual water projects -- whether single or multipurpose -- cannot as a rule be undertaken with optimum benefit for the people affected before there is at least the broad outline of a plan for the entire drainage area. Although this paper concentrates on the Lublin region, some thoughts are also given to the related problems in the upper portion of the Vistula Basin. Information concerning the entire basin is problem-oriented. A description of the basin and its water resources is presented in some of the earlier IIASA documents. The paper ends with the formulation of a proposal for the Water Resources Sub-Project to be implemented within the framework of the Lublin-Vistula Research Program

Parasitism, Adult Emergence, Sex Ratio, and Size of \u3ci\u3eAphidius Colemani\u3c/i\u3e (Hymenoptera: Aphidiidae) on Several Aphid Species

Aphidius colemani Viereck parasitizes several economically important aphid pests of small grain crops including the greenbug, Schizaphis graminum and the Russian wheat aphid, Diuraphis noxia. The ability of A. colemani to switch from S. graminum to several species of aphids common to agricultural and associated non-agricultural ecosystems in the Great Plains, and the effects of host-change on several biological parameters that influence population growth rate were determined. Female A. colemani parasitized and developed to adulthood in nine of 14 aphid species to which they were exposed in the laboratory. All small grain feeding aphids except Sipha flava were parasi­tized. Two sunflower feeding species (Aphis nerii and A. helianthi) and two crucifer feeding species (Lipaphis erysimi and Brevicoryne brassicae) were parasitized, as was the cotton aphid. Aphis gossypii. The average percentage of aphids parasitized differed significantly among host aphid species. as did the percentage of parasitoids surviving from the mummy to the adult stage and the time required for immature development. The sex ratio of adults that enclosed from the various hosts did not differ significantly among species. Dry weights of adult parasitoids differed significantly among host species. Adults from S. graminum weighed most (0.054 mg) while those emerging from A. helianthi weighed least (0.020 mg). Results are discussed in terms of strategies for classical biological control of aphid pests of cereals

An Interactive Procedure for Multiobjective Analysis of Water Resources Allocation

This paper reports on part of IIASA's research concerning regional water management planning, focusing on the Western Skane region in Southern Sweden. The IIASA studies are concerned with four issues of particular importance to water resources management, namely, conflict resolution, criteria of choice, uncertainty, and institutional arrangements. This paper is related primarily to the first two of these issues. An interactive procedure seeking the satisfactory nondominated solution of the multiobjective water resources allocation problem is discussed. It is based on the Powell method with penalty function for the solution of scalar optimization problem and on a constraint and weighting method, or actually a reference objective method, for the solution of the multiobjective optimization problem. Application of the procedure is illustrated by an example referring to the situation in the Kavlinge River system in the Western Skane, Sweden

The Management Alternatives for Control of Nonpoint Nitrate Pollution of Municipal Water Supply Sources

Regional water management aims at satisfying different supply interests, where these interests are often conflicting. In particular, the competing interests of agriculture, the environment, and municipal water supply, are becoming increasingly important. In this setting of regional water management, nonpoint nitrate pollution of municipal water supply sources is one of the most severe problems. At present, this problem is particularly acute in developed regions with high levels of fertilizer application, but undoubtedly in the future, regions which are now in a developing stage will also face the same problem. So far, related research at IIASA has been concentrated in Task 3 of the Resources and Environment Area on "Environmental Problems of Agriculture." This work has dealt in particular with agricultural-environmental processes as they are related to crop production and thus has also provided insight into the important role of agriculture in the nitrogen cycle. Yet another side of the problem remains to be considered, and this is related to water supply and management. This paper therefore proposes a study on management alternatives for control of nonpoint pollution of municipal water supply sources. The study aims at integration of the already initiated studies on "Environmental Problems of Agriculture" with IIASA's water management research. At the same time, due to the role of agriculture in this study, the study will be integrated with IIASA's Food and Agriculture Program investigations. Moreover, because of the need for modeling techniques in analyzing the problem in question, the study will utilize the research results of IIASA's activities on ecological and water quality modeling and the research pursued by the Systems and Decision Sciences Area at IIASA. Due to the importance of the problem for the majority of IIASA's National Member Organizations an international study involving IIASA and several institutions of different NMO countries is proposed. Therefore, the paper has been written in a specific form and is to be considered a tentative plan for collaboration within and outside IIASA in order to achieve more comprehensive research results. We would therefore like to ask our readers for any comments, remarks, or suggestions that could help to improve the course of our future activities