Suitability Assessment of Rural Settlement Land-use Using Systematic Model in Ziarat Watershed, Gorgan

Land use suitability assessment is necessary to prevent and imporove environmental issues. Land use planning provides a basis for decision making in spatial planning and land-use management. Selecting the appropriate land-use type and pattern according to ecological suitability of lands is the main purpose of watershed management and can lead to the control and decrease of the undesirable effects of natural disasters. Land-use planning provides the basis for considering the land management and also the natural and anthropogenic hazards necessary for the developmental process of land management. The arranement of relationships among people, land and human activities, and the sustainable utilization of human and environmental resources is important to improve the material and spiritual conditions of the community wellbeing over time, which is one of the main objectives of ecological potential assessment.
Theoretical framework: Land-use planning provides a basis for decision making in land-use management. The residential areas are affected by the changing dynamics of land use through an increase in the density of the area. Population growth increases the needs for recreation and accommodation, which leads to degradation of soil and natural resources. The increasing population growth along with the need to ensure food security in Iran is one of the main reasons of the conversion of forests and grasslands into agricultural and settled regios of the counry. Different criteria can be employed to plan the residential areas and the land-use suitability assessment at both local and national levels. Land use influened by dynamic human needs and environmental features varies with changes in lifestyle. The persistent engagement and conflict between human and environmental needs causes changes in land usage patterns, structures, and comopision at different spatial levels and time frames.
The present study was conducted in Ziarat Watershed located in the southwest of Gorgan City, Golestan Province. The intensive settlement growth and land-use conversion has occurred in Ziarat Watershed due to its favorable climatic condition and geographical location. Nowadays, the Ziarat watershed is in a critical condition due to the influence of human societies in terms of tourism and settlement development and it is necessary to conduct environmental assessment studies before implementation of development programs. The suitability of land resources was evaluated using the Systematic Model of Iran and the GIS tools.
According to the land-use map (2001), the extent of residential areas has been calculated to be 111.82 hectare. While the residetial aeas reached to 235.17 hectare in 2011 due to the extensive construction of new buildings and villas. Three residential categories were identified, including the favorable areas, the appropriate areas, and the inappropriate areas. The analysis of favorable and appropriate categories showed that the route development does not comply with the proposed development appraoch. The amount of overall Kappa index (0.3164) was within the range of low conformity, and the partial vakues of Kappa index were 0.2037 and 0.161 for the favorable and appropriate categories, respectively.To sum up, the both favorable and appropriatecategories were in the poor range of conformity. The results indicate that 4.46% and 4.52% of the study areas were assigned as suitable for the first and second categories, respectively, whereas the remaining areas (91.76%) can be consider as an unsuitable category for settlement growth. The comparison of settlement in the categories shows that the current condition of settlement growth is not in conformity with the ecological planning program. According to the results, the value of overall Kappa index was 0.3164, which can be assumed as a low-agreement settlement category. Also the values of Kappa index for the first and second categories were 0.2037 and 0.161, which fall into weak categories with low conformity. According to Kappa index values, the residential development does not comply with the current status while the developmental conditions of the residential areas, roads, and tourist facilities have damaged the study area. In the study area, the agricultural lands and forests restricts the residential development according to the results of the Systematic Model of Iran.
Conclusion and Suggestions: The current settlement development categories are not in conformity with the ecological planning program based on the obtained Kappa index value (0.3164). This kind of evaluation can be used to assist the designers of settlement development to plan to reduce the damages caused by natural hazards at local and regional scales. Ineffective management and inappropriate pattern of land-use patches regarding the ecological suitability has complicated the issue of the dvelopment of residentail areas. In fact, the ecological capability of development in residential areas was considered asa comprehensive approach to all ecological parameters of land management. In this sense, physical and biological parameters were identified and analysed; therefore, the sustainable developmente of residential areas include activities to stop or reduce the degradation, or at least slow down the destructive effects of previous undesirable utilizations in order to move towards the sustainable management of residentail areas at a watershed scale.