Suitable site selection for pistachio (Pistacia vera) by using GIS and multi-criteria decision analyses (a case study in Turkey)

Abstract

Efficient use of natural resources is only possible with rational management techniques. Land is one of the most important natural resources so it should be managed in accordance with its capabilities, properties and capacities for sustainable use. Land is, however, finite in extent. The combination of population growth and the growing need for land for non-agricultural purposes increases the pressure on competition for land. Therefore, land evaluation and land-use planning are becoming major issues for future use of it. The aim of this study is to determine suitable sites for pistachio (Pistacia vera) cultivation by using basic soil properties, climatic data, elevation conditions, geographical information system (GIS) and multi-criteria decision analysis (MCDA) in the Gulf of Edremit region-NW Turkey. In this study, literature and expert opinions were used to determine the requirements for pistachio cultivation. In the study, land-use capability classes, soil depth, soil limiting factors (drainage and salinity), mean temperature and critical period mean minimum temperature data for April and May, elevation and aspect data were used. An analytical hierarchical process was used to assign weights to the land characteristics used in the study. All data were transferred to GIS for further analyses. With overlay analysis, suitable sites for pistachio cultivation were determined. Suitability classes were reclassified according to the FAO (A framework for land evaluation, vol 22. International Institute for Land Reclamation and Improvement, p 87, 1977) framework. As a result, it was determined that in the Gulf of Edremit region 27,898 ha area is highly suitable, 8409 ha land is moderately suitable, 12,172 ha land is marginally suitable and 247,623 ha is not suitable for pistachio cultivation. The proposed methodology enabled the selection of suitable sites for pistachio cultivation for the first time by using GIS and MCDA. Soil and land are the basic natural and almost non-renewable resources for agriculture and other uses. The management of natural resources is a prerequisite for economic development and protection of the environment. For conserving precious natural soil resources, countries must have set up national land policy. The physical plans and land suitability analyses such as proposed in this study can help the protection of the environment and to assist for future land-use policies.