نشریه جغرافیا و برنامه ریزی محیطی
سال بیستم شماره 2 (پیاپی 34، تابستان 1388)

The aim of this paper is to investigate the function and role of small cities in Yazd province in urban system and regional development. The research method is descriptive – analytic. In which the quantity models and regression method and also data programs named SPSS are used. There are five small cities in Yazd province (25-50 thousand population) namely Ardakan, Meybod, Bafgh, Mehriz and Tabas which consist about 26 percent of urban population in the province. According to the surveys through Rank – Size Rule, in 1385, the linear gradient of Rank –Size Rule increases from - 1.652 including small cities to -1.745 excluding small cities. Economically industry & services are two basic parts in small cities which in central cities have followed an ascending model over the years of the survey. The linear trace of regression equation in all of these cities reveals that the agricultural part is below regression line, the service parts is on the line & Industry is above the line. This indicates the importance of industry in small cities. These cities have positive effects on urban. System of the province regarding population and economy. What has diminished the function of these cities in urban system and regional development, is the lack of minor cities in the urban hierarchy & the intense centralization of facilities in Yazd city, As a result, supporting small cities & allocating investment into them is a suitable solution in achieving balanced spatial structure in the surface of province

The pattern of urban spatial- physical growth or form define as spetial pattern of human activities in specific time, and divided in two main forms: urban sprawl and compact city. The recognition of physical development pattern is a fundamental task for sustainable development of urban areas. Tehran selected as a case study and research method is analytical –descriptive method. 4 methods proposed by Tsai are used: agglomeration grade, equal distribution grade, density and metropolis size.The result of this research show that Tehran had a slow growth and compactness in the past, but along with speed urbanization and urban migration, area grow so fast than we can named it urban sprawl. Of course in recent years, it tended to compactness and agglomeration. In conclusion, regard to undesirable consequences of this growth pattern and for achieving to urban sustainable development, policies and strategies must used.

The plain of Lower Jarghouyeh which is located in the southern part of the province of Isfahan is a suitable environment for the cultivation of the plant of pistachio. In this research has been used of attributive, compound and comparative and a pilot area was established in Lower Jarghouyeh and monitoring of phonological and aero logical conditions of the growth of pistachio were carried out for a year in 1383-1384. The recorded data combined with the secondary data were analyzed through the application of SPSS and EXCEL software. The analysis has concluded that the biological activity of pistachio lasts 273 days in which the planet needs 4234. 6 degree-days for different stage of growth. While rainfall and radiation are the limiting factors, relative humidity and soil conditions of Lower Jarghouyeh haven’t demonstrated any limitation for pistachio growth, but a cold spring and early low temperature in autumn are the hindering environmental factors that even stop the germination process. Although temperature is start and motor of wakefulness of growth in period of biological active in each plant, but it can stop or it can dispatch the plant. Knowledge suitable and necessary temperature and so degree of extent in each phonological period by total earned temperature and so minimum and maximum temperature of tolerance of plant and so relative moisture and necessary water and soil are problems that those should pay attention for cultivation each plant. More over climatic knowledge in each region is a subject that it should pay attention for cultivation of each plant in all region and so, probability of faced of different stage of growth of plant with suitable and unsuitable happenings should be certain. In this research it was done for cultivation of pistachio.

The mountainous region of western Iran was regionalized applying R mode principal component analysis (PCA) and Cluster Analysis (CA) on 9 precipitation derived variables in 140 stations distributed across the study area. In this way, the used variables were reduced to 4 principal components and then rotated using Varimax rotation criterion. Applying a Hierarchical Cluster Analysis, Ward's algorithm, on principal component scores, the stations were grouped into 5 individual clusters. The results indicated that the study area comprises of 5 distinctive homogenous subdivisions. The topography and latitude play an important role in determining boundaries between identified subdivisions and existence of spatial differences between them as well. Investigation of time evolution of monthly precipitation across the identified sub-regions indicated that the month of maximum precipitation moves from winter in the south to spring in the north-western most of the study area. The existence differences between south and north of the study area considering the time of occurrence of monthly maximum precipitation implied that the precipitation laden mechanisms are different in south and north of the study area

Contribution of women in economical and social activities and planning for more participation of them is an essential prerequisite for sustainable development. This is more important in rural communities of which the women contribution in household economy has been considerable forewore.In this study, the economical contribution and activities of rural women in Baraan rural region has been investigated. The research method is a description_ analytic survey and relevant date have been collected by interviewing the 15-65 ages rural women of the region the size of the sample was 164 persons from 9 villages which have been selected via randomized clustery method through different age categories. The main questions about the role of rural women economical activities in rural economy of the region and also the favorable content of these activities have been in the core of concern. Some of the main results_ that were obtained by using of Factor Analysis statistical method _ were the income revenue motivation, contribution in household economy, employment for the rural women activities. In addition the attitude and satisfaction of the spouse and activity opportunities in the existing situations were the effective factors on these activities in the study region.

The city of Yazd faced with rapid horizontal growth during 1350s. Of course, growth in size and body of the city is not a problem by itself. However, [considering it with time or in other words] "rapid horizontal growth of the city" in comparing to the economical, social, cultural and political growth of city makes it a problem. This problem should be prevented of improved and of course it can be done by knowing creating factors and it's after effects. According to the research, on one hand, rural-urban emigration for finding a job is one of the major and effective factors in making this phenomenon in the city. On the other hand, rapid horizontal growth of Yazd causes center-suburb movement in the city which is one of its effect and result. Therefore, on one hand regional planning should be considered significantly for balancing the population also should be done all over the city for preventing immigration to Yazd. One the other hand, preparing a comprehensive program of city old texture is necessary for returning suitable condition of life to this texture. This research was done by descriptive-analytical and surveying methods by using techniques of library and studies and of course by filling out some questionnaires.

In this paper, in order to analysis tempo-spatial variations of extreme 24 hour precipitations in Iran, monthly precipitation data of synoptic and climatologic stations from beginning of establishment to Dec 2005 have been studied. Using these data set monthly digital maps with a spatial resolution of 15*15Km has been calculated. Dividing 24 hour precipitation to annual precipitation provided extreme 24 hour precipitation coefficient map. An agglomerative hierarchical cluster analysis then applied to highest 24 hour precipitation coefficient matrix. This analysis shows that there are four main precipitation regions in Iran. In region No.3 about 60-100 percent of annual precipitation may occur just in 24 hours. In region No.4 about 100-160 percent of annual precipitation may occur just in 24 hours. These regions more subject to the extreme rainfall. These two regions are located in southern half of Iran, along Persian Gulf and northern coasts Oman Sea.The possibility of heavy 24 hour precipitation exists throughout Iran, except southern coasts of Caspian Sea in four months Dec, Jan, Feb and March. Extreme 24 hour precipitations of Caspian Sea coasts have occurred in Aug, Sept and October.Because of the weakness of westerlies, possibilities of extreme 24 hour precipitation didnt exist in southern half of Iran from April to November