فصلنامه جغرافیا و پایداری محیط
پیاپی 17 (زمستان 1394)

Dust storm is considered as one of the most important challenges in the west of Asia which has been intensified in recent decades due to various reasons like drought. These storms move a huge amount of soil particles causing severe economic, social and health damages. Different research findings show that dust storm can be considered as the most important climatic hazards in Iran.The present study aims at recognizing dust sources and its removal centers located in the southwest of Iran's borders. Using coded meteorological data, 24 AVHRR images were selected from all images. Moreover, the particles were detected by using the well–known algorithm of dust detection including brightness temperature difference in the thermal infrared bands and false-color combination. Totally, 62 original points were recognized in the southwest of the country, although 3 effective regions in production of dust were introduced by using the obtained density distribution in GIS including the west of Ilam and its bordering with Iraq, the confluence of the southern border of Ilam, north of Khuzestan and Iraq and the regions around HoorAlazim pond.

Participation is considered as one the most important elements of successful implementation of rural development projects, including rural conduct plans. Since participation is not a process that could be imposed from the outside, it should be created through collective action and regular revision of popular ideas. The present study aims at investigating the factors affecting the participation of rural people in the preparation process of the rural conduct plans in rural settlements. In the present study, using the previous studies of universities, institutes and scientific journals, and scientific databases, the primary information about the factors influencing participation of villagers in the implementation of the rural guidance plan have been achieved. Moreover, required information was also obtained through questionnaires and observation in the field studies. The population included 12 rural settlements in Dashtestan County in which the participation of villagers in the implementation process of rural conduct plans has been remarkably significant. Based on Cochran formula, the sample size of the households which were interviewed included 257 households in which 136 households had participated in the rural conduct plans and 121 households had declined to participate in the plans. In addition, 28 people from the rural authorities (rural administrators known as Dehyar and members of the Islamic council) were also interviewed, so that we can compare the results. The findings show that, based on single sample t-test, the participation of the villagers in the preparation, adoption and implementation of the rural conduct plans was moderate. The review of the factors affecting the participation of rural people revealed that individual factors had the highest mean (3.67) in the level of participation, and the economic factors had the highest mean (4.01) in non-participation of the villagers. The villages of Nazar-aqa and Faryab had the highest and the lowest mean for the factors that can affect the level of participation respectively. In general, the factors influencing the participation explains 34.6% of changes in participation level of the villagers.

Rural sustainable development has different dimensions in which the dimension of social sustainability is of great importance. This dimension follows not only determining the minimum social requirements for long-term development but also recognizing the challenges ahead of the society performance for a long time. As a matter of fact, accessing social sustainability in rural areas requires the recognition and analysis of social sustainability of the villages. Therefore, regarding social sustainability, the present study aims at evaluating, analyzing and prioritizing rural area of Ghal’eh Biaban District (Darab City). The data are gathered through library method, (including books, articles, and statistics) and field method (the questionnaire in the frame of Likert range to evaluate and analyze social sustainability indices). The samples include the families of 7 villages with the population more than 20 families in which 10% of the population was chosen (185 people) as the sample families. Analysis of data was done using RALSPI model and statistical descriptive and inferential methods. Variance analysis was applied for explaining difference among villages in respect of social sustainability, and ranking cases was done through RALSPI method because of reducing substitution possibilities between indicators. This method requires weighting indicators, so the weight vector was calculated using entropy method whose results assumed as input of RALSPI method. The findings reveal that rural areas have higher than average social sustainability, although there are significant differences among the villages. Moreover, based on RALSPI method, it turns out that Fath Abad village has the highest rank of social sustainability while Bikh & Bongol the lowest rank of social sustainability.

Nowadays, the population growth leads to increasing the demand for food, which typically causes additional use of arable land and water. Improper use of the earth due to population growth leads to environmental degradation, economicandsocial challenges, low- income housing and migration to other part of country or the world. The most part of soil loss is through water erosion in the world. Gully erosion is a highly visible form of the soil erosion that not only affects soil productivity and restricts land use, but also threatens infrastructure.
The present research aims at studying and comparing soil characteristics of gullies formed in the two regions which are sensitive to erosion (Chabahar and Sistan). In the present study, the available Geologic maps, aerialphotographs, Jammab map and field observation were applied to find gully erosion region. The kind of dominant climate was recognized. Moreover, two gullies in each region were selected in which the gully morphometric and natural characteristic were measured. Soil samples were taken from, 25%, 50%, and 75% of gully length at each location which were analyzed for soil characteristic and pH, EC, SAR, CEC, ESP, SP and texture. The data were analyzed using SPSSsoftware. The findings indicate that there are no statistically significant differences among the region soil properties. The profile typesofgully-headin Chabahar and Sistan are cave and vertical, respectively.

Nomadic societies have had a very important role in the history of human societies. As a matter of fact, changing and transformation have always been accompanying these societies, although, after the industrial revolution, these changes occurred more rapidly due to the expansion technology. Todays, the role and importance of nomadic communities have declined for many reasons. Moreover, some profound changes have occurred in different aspects of their lives facing numerous challenges and opportunities. The present study aimed to identify change and transformation patterns in livelihood ness- Residential and explanation of them in Farsimadan ecosystem. This study is trying to identify the changes in the patterns of living and explanation of the ecosystem of Farsimdan tribe. This research is an applied one using qualitative approach and grounded theory. The sample was selected first with criterion sampling method and then snowball or chain sampling method. So finally the research reached to theoretical saturation via participatory research techniques and eventually deep and semi-structured interviews with 12 people. The results show that different patterns of livelihood have been formed included sedentary, semi-nomadic and nomadic cattle without livestock. Set of internal changes includes the weakness of tribal knowledge and new technologies in relation to livestock, population growth, lack of capital and migration to the city and labor shortage. External forces of change, including land reform, limited support from the government in terms of legal, regulatory and financial, entrance of services and facilities to the village, technology penetration among tribes, vulnerability tribes against natural hazards and human risk, loss of traditional management nomadic, changing the political structure. Combined forces of change include the loosening of nomadic life values, promoting the culture of consumerism" and urban lifestyle that played a role in the formation and pattern choices, strategies, challenges and opportunities for them.

The environmental hazards is always considered as a threat for human settlements. Their effects on rural areas and various regions of the country are different according to the type of hazards. According to various parameters such as geographical location of the villages, the physical-Spatial structure, and the risk-taking, rural settlements will experience the greatest crisis during the disasters. Identifying the vulnerability of rural settlements, regarding the variables and effective factors, is considered one of the prevention method, reduce damages and management of risks. The present study aims at prioritizing the villages of Khuzestan according to environmental vulnerability like the distance from the active geology fissures, soil texture, the features of geological structure, the distance from torrential plains, the distance from preserved regions and the degree of slope using fuzzy logic. The research method is based on descriptive-analytical one with practical goal and applicable in the region. Data analysis is designed and implemented based on fuzzy logic in geographic information system (GIS). The findings show that the Khuzestan province demands a lot of research in studies about prioritizing the vulnerability. According to the study on 1989 rural areas based on various scenarios including, relatively pessimistic scenario of 746 rural areas, relatively optimistic scenario of 3 the rural areas, balancing scenario of or the weighted linear combination of 98 point of rural areas, they have the value of standardized environmental vulnerability more than 0.5. Moreover, based on the pessimistic scenario, all rural settlements of the region have more than 0.75 standardized value of environmental vulnerability, while based on the optimistic scenario, all rural settlements have zero standardized value of environmental vulnerability.

Crown dieback is a manifest phenomenon that occurred in the Zagros oak forests during recent droughts. Since the effect of crown features on the presence of mistletoe and on the trees have been proven, it is necessary to investigate the relationship between the dieback and the characteristics of tree canopy of the trees with mistletoe. So the investigation of the spatial distribution of parameters related to dieback of trees is important in order to manage and control the mistletoe in The Zagros Forests and prevent damage to trees and. Therefore, the plots (1600 m2) in a 200 m × 200 m sampling grid were established in Gahvareh Forests. Then Data were analyzed using geo-statistics (variogram) in order to describe and quantify the spatial continuity of variables. The range of the variogram for tree height is: 4110, tree height with mistletoe: 4227, average diameter of the tree crown: 4110, canopy diameter of tree with mistletoe: 4110, crown shape ratio of the tree with mistletoe: 5110, crown area of the tree with mistletoe is 2053 and the percentage of crown dieback of trees with mistletoe is 4110. The range of height, tree height with mistletoe, average diameter of the crown tree, tree crown diameter with mistletoe and the percentage of crown dieback of trees with mistletoe are similar proving that these factors have a greater impact on the distribution of this variable.