نشریه جغرافیایی سرزمین
پیاپی 22 (تابستان 1388)

In order to identify critical sediment sources in large catchments, using easilyavailable terrain information at regional scale, a methodology has developed to obtaina qualitative assessment necessary for environmental management. So it has been triedto study and used Fargas and etal, method in this research. This has been done in oneof the sub-basins of Hable Rood basin called Sangab with an area of 7684.71 hac inNE Iran, arid and semiarid climate of Iran. The main objective of this model is to usebasic terrain data related to the erosive processes that contribute to the production,transportation and accumulation of sediments through the main water paths in thewatershed. This model is based on the selection of homogeneous zones regardingdrainage density and lithology, achieved by joining the basic units by a rating system.The values of drainage density are rated according to an erosion class. The lithology israted by erosion indexes, adapted from FAO (1977). The combination andreclassification of the results brings about five qualitative classes of sediment riskaccording to Fargas and etal (1997). The privileges of this method is, it used only twomain factors of the erosion, that are lithology and drainage density, and this factors arein our geologic and topographic maps in Iran. The mapping scale was 1:50000 and themodel were implemented through a vector GIS (Arc GIS9.2). The tested methodologyhas been proved useful as an initial approach for erosion assessment and soilconservation planning at regional level and also to select priority areas where furtheranalyses can be developed and finally for environmental management.

The Shanghai Cooperation Organisation (SCO), Currently consisting of China,Russia and four Central Asian states (Kazakhstan, Uzbekistan, Kyrgyzstan andTajikstan), covers more than three fifths of the Eurasian Landmass and represents onequarter of the world population. Hn that sense it is the biggest security organisation inthe world next to the UN.The SCO is also the only international security organization,where China is a member and the United States is not.As will be demonstrated belowcentral Asia is at the centre of the organisation both in a geographical and politicalsense.if India, Pakistan and Iran, which joined the organization in 2005 as observers(Plus Mongolia in 2004) are included, the organization represents about half the worldpopulation and contains four nuclear powers.The organzation calls for greter economic cooperation among its members ,and at ameeting on September 23, 2003, Wen Jiabao, the premier of the Peoples Republic ofChina (PRC) ,proposed the establishment over the long term of an SCO – wide freetrade area designed to improve the flow of goods in the region by easing traderestrictions, such as tariffs.The SCO, s Security agenda is vast.The organization has been compared to theWarsaw pact and referred to as the " NATO of the East.

Today, development and rural development are important themes in developingsocieties that theirs aim are to pursue approaches that helps to improving rural peoplecondition. This subject urge some countries that focus on growth untill developmentand it results the countries have problem in distributimg profits of development. Forsolving this problem, in developing countries, many tools presents untill decrease gapamong people groups, for example land use & Agronomy reform. Land use is forequal disributaion among people, and agronomy reform help to reconstruct economic& production of society in the country. Thus it is essential that we notice to landscapeassesment and space. In this direction, it is important that define earth and presentearth assessment.

The study area is a part of Karoon river located in Khuzestan province in southwestof Iran. The length of this reach is about 364 km from the north of Shoshtar to theArvandrod. The changes and local difference on the river reaches consider togeological, tectonicaly, hydrological and artificial parameter in the dry flood plain ofKhuzestan has caused some damages, risks and hazards during the time. By recognizeof fluvial environment of Karoon River and determining the changes of the river,control of these hazards is possible. Because of morphometric characteristics study ofKaroon River, for changes prediction, with use of satellite images of IRS and land satin the years of 1991 and 2007, channel length of the river has drawn, measured andanalyzed by GIS software. so total length of Karoon consider to the number of theircurves(100 curve) divided to smaller limits and crossing point selected as upper andlower limits of each curves. Then geometric parameter of channel like radius ofcurvature, mean central point of each curve, curve direction and annual rate of channelmigration measured. The results show that the most risks belong to meanderingreaches. Therefore the land use and sensitive area of river to erosion spatially oncurves if dose not controlled. There are a lot of area like farms, roads, settlement,national fields and other mankind Struthers that will be destroyed.

Recently progression of Remote Sensing caused that the changes were studied moreaccuracy and fast with less expenses. Method of change detection is a important wayto defined changes in costal in time ranges. Most of landforms in beach were collapsebecause of develop of petroleum in costal of Iran. Since petroleum installations wereexpanded in Asalooyeh costal, therefore this spot is one of the area where destroyed inIran. In this research coastal zone was taxonomy based on Geomorphology andIKONOS images in 2000. In the following changes of landforms were studied by IRSimages during 6 years. Unsupervised classification method, change detection, high &low position, statistics analyses and field research were use in order that the land formschanges were reconnoitered and the result were studied in Geography InformationSystem. In effect 85 % of geomorphologic landforms were collapsed because ofindustry installation. There are small gulf and marsh. The rest was destroyed. Some ofthe organizations in Iran make a preservation of natural environments.

Catchment of Garangoo is as a semi-arid region (from 46゜. 27´ to 47゜. 42 E, from36゜. 58´ to 37゜. 44´N) and is as largest catchment of Sahand mountain. The RockFalls and Rock Flows, as one type of mass movement and as marked ofgeomorphologic hazard, frequently are occurred on rocky slope of semi-arid mountain.These events are the natural outcome of natural processes which the occurrences ofevents are intensive with human impacts and are threat the human structure ,speciallyin mountain area and are imposed economical damage to villager The environmentmanagement is require firstly, to study mechanism of the occurrence of these eventsand then zonation of susceptible area to the occurrence events. The aim this article isassessment share of factors and is define share of 10 factors on the occurrence of Rockflow. The Rock flow hazard mapping is often performed through the identification andanalysis instability factors .For mapping ,firstly distribution map of factor produce anddigitized of factors and then analyzed by bivariated methods and the next stage,weighted to factors and final stage, produced Rock flow hazard zonation map by usingof Arc/View .This map show that, large part of Garangoo catchment is consist ofvolcano ash ,marl and old alluvial ,with steep slope at site of 2000 m altitude. Thevolcanic material (andesite and dasite) specially Miocene volcanic stone,produced thedebris and rock segments. These materials deposited on roads surface and distortedpassengers.

West slopes of bagrodag and fandoglu area, with having unique autumnal forests,beautiful and green pastures and naturel and human making extents, that is one of thewell-known natural attractions in west-north of country, has been situated in the endwest of ardebil province.In this research, in order to survey existing relationships of vegetation in area andits forest distribution,with environmental factors and identification of limiting(preventing) factor and identification of effective factors in its area formation, withsurvey of any environmental factors, commence of providing different environmentalmaps from a direction and vegetation maps from the other direction and finallycombined maps from them has been done.With survey of these maps, has been recognized that none of climatic factors,preventing or limiting factors, in forest formation are not considered. But these factorsare effective in the kind of vegetation. Among these, two factors of humidity and thedirection of wind, have been effective more than other factors and due to have rates ofarea and plant community from passing humidity of area level, play role in thevegetation concentration and its present.Trough, continuosly protection of forest and pasture areas has been done and thecmpletness of growth stages has been provided for plants, can be hoped to makingforest areas in all over the study area.

Tehran city, with regard to urban making standards and geographical definitions, isidentified as a metropolis and the issue which constantly comes up in this city, isearthquake crisis management. And the main question is that whether the structure ofexisting organizations for managing the quake crisis is responsible?In this article it has been tried, to explaning crisis and crisis management, Tehransituation and quake risks, vulnerability and quake consequences and prediction offuture in Tehran. It is identified that this organism is not responsible for crisismanagement in Tehran metropolis, because the existence of 24 issues and challengestoward the management of quake crisis in Tehran. They are identified by interviewwith experts and managers and eventually to remove them and create the qualifiedmanagement, the12 items suggestions are recommended, the most important of that is:To establish an integrated urban management in a way that all sources of power,including public forces, civilian police and military forces, public institutions undermunicipality and popular institutes to be responsible before the head of crisisheadquarters(e.g. Tehran mayor), in fact, structural and legal problems to be resolvedand the powers of crisis manager to be increased.