ارزیابی شرایط مناسب برای فعالیت شنا در سواحل استان گیلان

Introduction
Ecotourism as a shortened term of Ecological Tourism is the possible leisure activities of people in the nature. It is based on purposeful trips for visiting nature and cultural and spiritual perceptions of natural attractions and also for enjoying a variety of natural phenomena (Rezvani, 1380). Generally, visiting nature makes ecotourism different from other kinds of tourisms (Zahedi, 1382).
Dynamic nature and a variety of leisure activities available in coastal areas, has made the areas highly favorable for tourists. This has transformed coastal areas into one of the most influential regions for local and national economies in the world. Climate can also affect attractiveness of places for tourists and may have a major role in selection of tourist sites. Based on past evidence, climate can be a key factor in vacation planning and satisfaction of vacation experience so it is known as a central stimulus for vacation planning. One piece of information that tourists need to know for vacation is the climate of destination cities. Most of the tourists take this factor into account for choosing their destination. However, climate has a low presence in tourism literature, while it is highly important in vacation planning of tourists. Considering above-mentioned issues, no comprehensive and detailed work is carried out on standard conditions of swimming in coast areas of Caspian Sea. This paper has studied the subject as the first.
Methodology
In this research we have tried to reveal one of these tourism potentials, that is, swimming activity in the southern coast of the Caspian Sea in Gilan Province. For this purpose the hourly data of temperature, wind speed, relative humidity, and sun shine duration were obtained from the Meteorological Organization of Iran for the period 2005-2008, the period when the sea surface data such as wave height and temperature were available. The data have been analyzed for the stations of Astara, Anzali, and Lahijan.
It is worth noting that, a survey from a sample of fifty people of Tehran citizens had a major role in form of the tourism. Tourist activities have been examined in this study and this make it possible to find out the demands of tourists according to the survey. Among the four options of: 1) the beach and the sea, 2) forest and mountains, 3) ancient monuments and culture of the area –customs, and 4) souvenirs, about 46% of the tourists introduced the beach and sea as a main tourist attraction in Gilan. From the four activities of 1) surfing on the beach, 2) swimming, 3) boating, and 4) fishing, the swimming was the activity 50% of the respondents in both cases had the highest demand among all other options. Selection of beach, sea and swimming activity by the tourists helped choose the type of tourism and the specific tourist activity in accordance with the following model. Marine tourism» Beach tourism» Beach sport» Aqua» Swimming
According to the data a suitable indicator of environmental conditions was first created for swimming in the lake. This index includes the suitable temperatures for environment, the suitable temperatures for water, maximum wave height that is permitted to swim, maximum wind cooling does not cause discomfort in people, no phenomenon of lightning, and no rain. This index is called the standards of swimming. Then the factors have been taken from above-mentioned stations filtering the days when the facts were consisted of suitable days for each station according to the annual, monthly, weekly, and weekend intervals. Referring to this stage it was clear that, which month, which week and which weekend were the best times for swimming activities in each station in the Caspian Sea.
 
Results and Discussion
The best days have been viewed and compared in two hours of 9:30 am and 15:30 pm at three stations studied during timescales annually, monthly, weekly and for weekends. It was found that the rate of good days for swimming activities in the coast of Gilan at 15:30 pm is more than those in 9:30 am.
The results of this study indicated that, in addition to other factors involved in standard conditions for swimming, solar radiation is the most important factor in choosing the appropriate time for swimming ashore. Because it has a direct effect on factors determining the appropriate time of swimming such as air temperature, water temperature, wind speed and cool and etc., the sun is, indeed, neutralizing their negative effects.
 
 
 
Conclusion
The results have indicated that the best months for swimming, in order, are August, July, June and September. Astara is the most suitable sea side for swimming during week days and weekends. Anzali and Lahijan are the second and third best places in order.