WIT Press


ASSESSING LAND DEGRADATION HAZARD INTENSITY AND MANAGEMENT PLANS USING SUBJECTIVE MODELS AND THE ANALYTICAL HIERARCHY PROCESS IN GORGAN, IRAN



Price

Free (open access)

Paper DOI

10.2495/SDP-V4-N1-35-45

Volume

Volume 4 (2009), Issue 1

Pages

10

Page Range

35 - 45

Author(s)

M. OWNEGH

Abstract

Land use planning is a comprehensive master plan for any sustainable development action plan and can integrate all land resources and natural hazards management alternatives (strategies, plans and scenarios). This can be done via a multi-attribute decision method such as Analytical Hierarchy Process (AHP) under data and decision uncertainty. In this paper, first, the potential land degradation hazard was mapped at 1:250,000 scale as four hazard classes. This was done in the context of 14 micro (unit) and six macro (type) physiographic units, regarding the synergetic effects of five key processes (salinization, ponding, water erosion, wind erosion, and vegetation deterioration). A five-class numerical subjective model was used. Secondly, with respect to the nature of land degradation mechanism and intensity in the Gorgan coastal plain (a complex mosaic for land use planning and natural hazard management) four hazard mitigation plans were proposed These were aligned with the goals of national combating of desertifi cation. These include: (1) Drainage and surface flow water collection, (2) shrub plantation and green belt creation, (3) soil physicochemical improvement, and (4) protection and preservation. Finally, the relative weights and priorities of management plan alternatives were determined in each hazard class zone. This was accomplished with respect to the hazard intensity and plan implementation cost and effectiveness using AHP model (CR=0.04 for plans, and CR=0.03 for hazard classes). The results indicate land degradation hazard classes I, II, III and IV which are extended with a spatially ordered pattern from forest covered mountain in the south to steppic coastal plain in the north along a sharp geo-ecological gradient of the study area. The differences of hazard class weights and surface areas, and the priority weights of the plans are signifi cant at 0.01 and 0.05 level, respectively. These differences lead to different possible alternatives for hazard management plans and decision making.

Keywords

Analytical Hierarchy Process, Gorgan Plain, hazard management plan, land degradation, land use planning