Özet:

The Muğla district located at the southwest part of Turkey, which is characterized with typical features of the dry summer subtropical Mediterranean climate and the Mediterranean ecosystems, has hosted some of the important nature areas of Turkey. In another words, Muğla is one of the unique city provinces in Turkey by having the significant potential in terms of its diverse biotope (e.g. bays, lagoons, coastal and forest ecosystems, etc.), biota (flora and fauna), endemic and relict species, water resources, and environment and nature protection areas with the various statues. In the study, we used the climatological data recorded at the Muğla Meteorology Station in the period of 1928-2010. Firstly, by making use of this data, time-series of the Normalized Precipitation Index (NPI) and the United Nations Convention to Combat Desertification (UNCCD) Aridity Index (AI) were calculated and the observed droughts and wet years were detected. Secondly, by determining severity levels of the drought and wet conditions, likely negative impacts of these conditions on the important nature areas of the Muğla district were evaluated. In this context, response measures suggested to be taken to likely consequences of these adverse impacts were also discussed. Finally, the nature and magnitude (i.e. statistical significance) of the climatic variations in the district were investigated by regarding results of the analysis methods for the randomness and trends applied to the NPI and AI series. The main results of the study are as follows: (i) The driest years in Muğla were of 1934 and 2008, while the wettest period was 1937 to 1940. (ii) There is a strong association between the magnitudes of forest fires and fired forest areas and severe dry conditions occurred over the Muğla district in the drought year of 2008. (iii) Correlation analysis indicates that there is a very strong positive relationship between the NPI and the AI series with the magnitude of a correlation coefficient r = 0.99 (p << 0.001). (iv) Resultant test statistics of the trend tests applied to the NPI and AI series are not statistically significant. (v) Adverse impacts of the observed and predicted climatic variations on the water resources and forest fires, such as increases in air temperatures, heat waves, drought events, severe (extreme) rain showers and hail storms, and further longer and more severe summer dryness, are very likely at the level that may cause losing the unique and rich ecological, biogeographical and biodiversity values of the important nature areas of Muğla. (vi) Consequently, as in whole regions and districts characterized with the Mediterranean climate, the probability that may make much more difficult to protect the important ecosystems and unique biodiversity of the Muğla district in a near future should be taken into account in all nature protection, forestry and water resources/drought management actions and studies. Key Words: Muğla District, Mediterranean climate and biome, climate change, forest fire, drought indices and time-series analysis methods.

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