Türkiye’nin merkezî yerler sistemi ve bu sistemi oluşturan çeşitli kademelerdeki merkezî yerleşimler DPT tarafından 1974’te yapılan ampirik bir araştırma ile 1970 yılındaki idarî bölünüşe göre belirlenmiş idi. Bu çalışma kapsamında ise Türkiye’nin bütün merkezî yerleri 2000 yılı idarî bölünüşüne kadar izlenmiş ve bu yerleşimlerin 2000, 1985, 1970 ve 1955 nüfusları, bugünkü idarî sınırlara göre tespit edilmiştir. Aynı zamanda 50000 ve üzeri nüfuslu bütün yerleşim birimlerinin metropoliten alanları Berkeley Uluslararası Kentsel Araştırma Enstitüsü ilkelerine ve 2000 Nüfus Sayımından elde edilen istihdam verilerine göre elektronik ortamda harita üzerinde belirlenmiş ve bu kentlerin metropoliten nüfusları tespit edilmiştir. Her bir kademedeki yerleşimlerin toplam nüfusları incelendiğinde genellikle ilçe merkezlerinden oluşan 3.kademenin en kalabalık kentsel kademe olduğu ve bu özelliğini –İstanbul’dan oluşan 7.kademe oransal olarak daha hızlı artmasına rağmen– 1955-2000 dönemi boyunca koruduğu görülmektedir. Bölgesel merkez düzeyindeki 5.kademe en zayıf kentsel kademe olarak göze çarparken, 1985 öncesi dönemde başkentin de içinde bulunduğu 6.kademe, 1985’ten sonra ise sadece İstanbul’dan oluşan 7.kademe toplam kentsel nüfus içindeki payını en çok arttıran kademelerdir. Farklı kademelerdeki yerleşimlerin ortalama nüfusları ise incelenen dönem boyunca değişen oranlarda artmakta ancak 1.kademe yerleşimlerde (köylerde) 1985-2000 döneminde ikili bir gelişme yaşanmaktadır. Köylerin büyük çoğunluğu nüfusça küçülürken, bazı köyler nüfuslarını artırmakta, bu arada ortalama köy nüfusu azalırken toplam kır nüfusu sabit kalmaktadır. Önümüzdeki yıllarda ülkemizde bulunan 80000’e yakın kırsal yerleşimin bir bölümünün varlığını sona erdireceği, belirli köylerin ise etki alanlarını yok olan yerleşimlerin arazilerine doğru genişleteceği düşünülmektedir. Anahtar Kelimeler: Merkezî yerler kuramı, log-normal dağılım, yerleşim birimi, metropoliten alan, kırsal nüfus.The central place system of Turkey and its components –the central places at the various levels– were revealed by State Planning Organization with a thorough and extensive empirical study undertaken in 1974 and published in 1982. Since then, numerous administrative changes have made it impossible to track all central places from 1974 within the current administrative division of the 2000 census, thus, hindering any long-term study of changes in populations of central places. Within this study, all central places from level 2 to highest level 7 have been tracked within the 1985 and 2000 censuses, as a result, a complete list of central places in accordance with the 2000 administrative division has been prepared indicating their 1985, 1970 and 1955 populations –reflecting the current administrative division. Furthermore, the metropolitan areas of all cities above 50000 population have been determined according to the principles set forth by the Berkeley International Urban Research Institute in 1959 using employment data from the recent 2000 census. Parr and Suzuki in 1973 and Parr in 1976 argued that the size distribution of settlements within a system conforms to the log-normal distribution better as compared to the rank-size distribution. The Turkish settlement system confirms their insight in that settlement populations within each central place level are distributed log-normally. Following Gibrat (1931) may researchers tried to explain the presence of rank-size linearity as well as log-normality with the ‘law of proportionate effect’ stating that within an urban system growth rates of settlements will be independent of their size. Growth rates of Turkish settlements, however, do differentiate among different levels of the central places hierarchy, thus, differentiating among size classes as well. Within this study the size distribution all settlements units regardless of administrative status and threshold figures are examined in terms of total and average (geometric mean) population figures (using MA population) of settlements within each central place level. Also the change in these figures over the period 1955-2000 is analyzed in 15-year intervals. While in 1955 more than two thirds of the population of Turkey lived in rural settlements (1st and 2nd level centers) by the year 2000 this proportion dropped to one third of the population. The internal distribution of urban population among urban central places (3rd to 7th levels of the central place hierarchy) also changed during the given period. While in 1955 3rd level central places (mostly comprising of district centers) contained the largest portion of urban population, the 4th level centers (mostly comprising of province centers) ranked second, while the 7th level (which is equal to the city of Istanbul) as the national economic metropolis stood at the third place. 6th level central places including the capital Ankara came forth while 5th level central places ranked last among the hierarchy in terms of total population which is not surprising as 5th level (regional) centers lack the corresponding local administrative structure compared to 4th and 3rd level centers which are generally province and district centers, respectively. By the year 2000 the most populated urban level is still the 3rd level though İstanbul has almost reached the total population of 3rd level centers, especially exhibiting a strong increase between 1985-2000. Also in 2000 5th level regional centers remain in the position of the weakest urban functional class. Looking at average population figures within each central place level and their growth over time a dual development can be observed. Central places at hierarchy levels 2 and above exhibit positive growth rates in terms of average settlement size –though the growth rates do vary significantly among hierarchy levels and between different periods in a direction where settlements at higher levels of the central place hierarchy also display higher growth rates compared to lower levels. 1st level centers (villages), on the other hand, exhibit negative growth rates for the period 1985-2000. While most villages shrink in size (contrary to all higher order centers), a small portion of villages gain or retain their population, in a period where total village population remains fairly stable. It is estimated that within the coming years some portion of the approximately 80000 rural settlements (including hamlets) in Turkey will cease to exist, while some other rural settlements will extent their area of influence onto the areas of the shrinking settlements. Keywords: Central place theory, log-normal distribution, settlement unit, metropolitan area, rural population
