67 research outputs found
Development of a Computerized Aid to Integrated Land Use Planning (CAILUP) at regional level in irrigated areas : a case study for the Qaun Lo Phung Hiep region in the Mekong Delta, Vietnam
The problem - Objectives of the studyLand use planning is an essential activity in any country, because the demands for different land uses usually exceed the available resources. Land use planning implies weighting of trade-offs among conflicting goals, as different interests exist in society. Demands for water often also exceed the available resources.The objectives of this study are to develop and implement a method and corresponding software system for integrated land use planning at regional level in irrigated areas, and to test the method and the system in the Quan Lo Phung Hiep region in the Mekong Delta, Vietnam. The System Development Methodology (SDM) comprising seven specific phases was applied in the study. A Computerized Aid to Integrated Land Use Planning, "CAILUP", was formulated.The research conceptThe greatest challenge in land use planning is how to incorporate the diversity in land use , comprising land users, goals, management and technologies, into the planning process. The CAILUP approach takes into account the diversity in land use by integrating promising land uses for agriculture, fisheries and forestry with land uses for other purposes.Integration is a major issue in land use planning. CAILUP focuses on integration of land use selections at different hierarchical levels, of bio-physical and socio-economic factors, of local expertise and global (international) expertise, and computer technology and land use planning.CAILUP takes into account integration among hierarchical levels by combining top-down and bottom-up approaches. Interventions are based on the goals of regional development in the context of the whole country. The feasibility of these interventions is judged by taking into account the preferences and priorities of the local land users, and subsequently all achievements and impacts from these interventions are evaluated. Decisions on land use can be considered as 'public decisions' with contributions from scientists, planners, decisionmakers, sectoral agencies and land users. Integration in 'public decision' is carried out by simulating the decision process.An IBS ( Integrated Bio-physical and Socio-economic ) approach is proposed to assess the effects of water management. Integration requires the equal resolution (in space and time) of data on both bio-physical and socio-economic factors. Land units are delineated by administrative boundaries and limits of key physical interventions.Land use planning can also be considered as a process of multi-sectoral integration . A key intervention is determined, i.e. construction of a water management system for an irrigated region. Other interventions are supplementary interventions to improve water management efficiency. A land use planning team needs to comprise a wide range of expertise . CAILUP comprises a knowledge base that integrates expert knowledge from both local (regional and national) and global expertise.Simulation modelling is a promising technique in land use planning to achieve integration. The strategy in modelling of CAILUP is to integrate simple sub-models of all relevant components, rather than only to include a few complex sub-models developed for single disciplinary research. CAELUP provides functions to analyse the impact of different hypotheses or scenarios formulated by planners. A scenario comprises a set of actions and effects in which goals are achieved to a certain degree. The impact of water management on the physical conditions is first evaluated. The new physical conditions lead to new biophysical production levels that are used to determine an integrated feasibility for each land use type by comparison with socio-economic criteria at farm level. This feasibility is used, in combination with Government policy objectives, to formulate a land use plan. Finally, achievements based on this plan and its impacts on bio-physical and socio-economic conditions are examined.Integration of computer technology and land use planning will be achieved by developing a system consisting of quantitative models, databases and GIS based on the concepts of decision support systems and expert systems.A Computerized Aid to Integrated Land Use PlanningCAILUP consists of four units : a core expert unit, a database unit, a GIS unit and a model unit. The model unit, a major component to realize the system function, comprises a mathematical model developed on the basis of a conceptual model.The conceptual model is developed in a sequence of identifying issues, goals and indicators, relevant land use types, relevant components, factors, spatial extent and spatial resolution, time horizon and time steps, and "without" and "with" intervention cases.The mathematical model comprises 14 sub-models:[1] Intervention Generating Sub-model to generate a data set for the "without" or "with"intervention cases.[2] Physical Impact Sub-model to generate a data set of modified physical conditions.[3] Bio-physical Sub-model (Agriculture, Fisheries, Forestry) to estimate yields and the selected crop calendars under modified physical conditions.[4] Economic Sub-model at Farm Level to generate the combined bio-physical/economic feasibility based on financial criteria defined at farm level.[5] Social Sub-model at Farm Level to integrate social preferences with biophysical/economic feasibility to generate integrated feasibility.[6] Demography Sub-model to generate data on population and labour force.[7] Land Use Weighting Sub-model to determine weighting factors based on the integrated feasibility and Government policy.[8] Land Use Allocation Sub-model to generate land resource use on the basis of the weighting factor and rules in land use conversion.[9] Production Sub-model to generate total production by multiplying area with yield.[10] Supplementary Intervention Sub-model to generate supplementary interventions required to support the land use scenario.[11] Economic Sub-model at Regional Level to calculate the economic returns at land unit and regional levels.[12] Social Sub-model at Regional Level to calculate the socio-economic indicators at land unit and regional levels.[13] Environmental Impact Sub-model to calculate indicators expressing environmental impacts.[14] Goal and Impact Analysis Sub-model to generate a ranking value for the selected scenario.An example in the real worldThe Quan Lo Phung Hiep region , with a total area of approximately 450,000 hectares and located in the Mekong Delta, Vietnam, was selected for the case study. Agricultural production in this region is constrained by adverse soil and water conditions. Low rainfall during the dry season prevents agricultural production without irrigation. However, salt water intrusion from the sea makes water quality in most parts of the region unsuitable for irrigation. In the early part of the rainy season, leachates from the acid sulphate soil area contaminate surface water and reduce its pH to values below 4, which is detrimental to agricultural and aquacultural production.In the region, 85% of the population is engaged in agricultural, fisheries and forestry activities. The relevant land use types are single crops (rice, sugarcane, etc.) or a combination of various crops/activities (double rice, rice+beans, rice+shrimp, etc.) under different management techniques. Rice is the most important crop. Living standards are reportedly lower in areas of salt and brackish water than in areas of fresh water.Water management to prevent salt water intrusion and to increase the supply of fresh water from the Mekong river is considered a key intervention for development of the region. Main objectives of water management are to increase total food production and income and to improve living conditions. A medium scale protection option, i.e. protection and irrigation of the central part by 11 medium-size sluices, was selected. Seven schedules of water management construction were formulated, depending on the availability of funds and the strategy in minimizing the acid water effects.Four land use strategies were formulated: Maximize rice production, Maximize income from rice production, Crop diversification and Minimize effects of acid water.CAILUP for the Quan Lo Phung Hiep region has been developed and used in analysing the effects of different construction schedules and land use strategies.Data used for calibration are data on water conditions in 1989-1990, data on yields from 1986 to 1990, data on population and land use areas in 1985 and 1990, and data on production from 1985 to 1990. Calibration of single sub-models was followed by calibration of series of submodels. The model then was validated with inventory data from 1991 to 1994.Twenty eight development scenarios combining 7 construction schedules of the water management system with 4 land use strategies, were compared with a "without case" in which the new water management system was assumed absent. Single goal scores and total score were used as main outputs for evaluation of development scenarios. Sensitivity analysis has been carried out to provide a measure of the sensitivity of the outputs to either parameters, functions or sub-models, and to analyse the impact of changes in values of inputs on scenario scores.A construction schedule was selected on the basis of development objectives and possible impacts reflected by scenario scores, taking into account the institutional situation in the region. Selection of a land use strategy is more difficult because each land use strategy has the highest score for at least one of the goals in the situations considered. A rice-oriented strategy has been selected, with more crop diversification outside of the protected area.Conclusions and recommendationsThe objectives of the study have been attained. Taking into account major issues in land use planning methodology, CAILUP was developed to facilitate integration in land use planning. A corresponding software system was developed and tested successfully for the Quan Lo Phung Hiep region. To be developed and applied successfully, CAILUP requires suitable conditions in terms of human resources, data and information, and hardware and software packages.Although the above conditions have been adopted, development and applications of CAILUP are still confronted with many challenges each deriving from the existence of two alternatives (see Chapter V: Section 2). A cycle exists in which one challenge becomes dominant and is the main subject of many studies during a number of years, and there is also a cyclic behaviour of the two alternatives of each challenge. The attempt in further studies is to develop and apply the CAILUP system adapted to these cycles
New Approaches to Support Development of Sustainable Land Use Systems
In this paper, the land use planning cycle is introduced and some recent efforts at developing appropriate methodologies for supporting some of its distinct phases are illustrated. The examples still largely bear an academic character, but since there is increasing demand by policy makers for integrated land use analysis studies, they may serve as building blocks for development of operational methodologies for land use policy ormulation and analysis. Their potential impacts on planning procedures and chievement of land use objectives are high, particularly when they are further developed and operationalized in settings that allow participation and involvement of the various user group
Constraints on agricultural production in the Northern Uplands of Vietnam
The Northern Uplands of Vietnam form one of the largest ecological regions in the country, characterized by complex biophysical conditions and a high diversity in ethnic minorities, cultures, and farming systems. The Doi moi (ārenovationā) program has, since the early 1980s, resulted in significant changes in agriculture production and related economic trends. However, poverty, low agricultural productivity, and land degradation are still major problems. This article illustrates the factors that drive these problems by analyzing agricultural land use in Suoi Con, a small agroforestry watershed in the Northern Uplands. We first identified the current land-use systems and analyzed constraints on agricultural production. The results indicate that although low soil fertility and land degradation are considerable problems, availability of household capital, low technology levels, and land fragmentation are major constraints on agricultural development. These constraints were analyzed from different points of view to identify mismatches between the implementation of top-down government policies and specific conditions that may explain why actual land-use change in the Northern Uplands deviates from the government's development plans. Results of land-use analysis in the Suoi Con watershed suggest that participatory and bottom-up approaches are needed to better understand problems and opportunities in household agricultural production in order to develop appropriate land-use plans and policies
Development of a Regional Interactive Multiple Goal Linear Programming Model with Can Tho Case Study as an Example
In exploring land use options, input-output relations pertaining to agricultural activities are fed into a linear programming model to generate optimum land use allocations to satisfy multiple goals and constraints. Different scenarios can be analyzed and estiĀmates of trade-offs in attaining various goals can be computed. This would provide a rational basis for making sound decisions regarding land use
Development of a regional interactive multiple goal linear programming model with Can Tho case study as an example
A systems approach to anakyzing land use options for sustainable rural development in South and Southeast Asia
The Project is currently approaching its mid term phase, and is organizing an international workshop on methodology exchange in land use planning (June 15-19, 1998 at Can Tho City, Mekong Delta, Vietnam). During 1997, much effort has been put into data collection and developing novel methodologies for exploring land use options at the regional (subnational) level; the various aspects of work being carried out have not yet been presented as a whole. It is timely and appropriate now to publish some of the ideas, approaches, and preliminary results and convey this information to specialized institutions, all collaborators in the Project, donors and clients, and individual subject matter specialists
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