Aim To define the bioclimatic tolerance ranges of the two Tabor oak subspecies. Prior to this definition, and considering the confusion in the literature regarding the Tabor oak subspecies geography, a reassessment of their present distribution is proposed.Location Turkey and the Levant. MethodsThe bioclimatic tolerance range of each subspecies was characterized by four parameters: (1) the humidity category (Q 2 ), (2) the winter variant (m)the two basic variables used in Emberger's method for the definition of Mediterranean bioclimates, (3) the length of the dry season (LDS) and (4) its severity, expressed by the dry season water deficit (DSWD). The reference to the last two variables in the definition of bioclimatic tolerance ranges of Mediterranean species has so far never been considered. The concept of bioclimatic niche, based on the reference to these four parameters, is proposed and discussed. ResultsThe reassessment of the Tabor oak subspecies distribution shows that their extents of occurrence do not overlap and are significantly distant. The comparison between the characteristics of each subspecies bioclimatic niche has highlighted three major differences: (1) The bioclimatic niche of the subspecies macrolepis is characterized by a great heterogeneity as it includes up to 10 distinct bioclimate types, whereas only four types have been found in the bioclimatic niche of the subspecies ithaburensis.(2) A 10°C gap has been found between the winter variants of both bioclimatic niches. (3) The third major difference relates to the dry season characteristics: the bioclimatic niche of the subspecies ithaburensis is characterized by an LDS 40-75% longer than it is in the bioclimatic niche of the subspecies macrolepis. Moreover, and surprisingly, although the most arid humidity categories are found in the bioclimatic niche of the subspecies macrolepis, the bioclimatic niche of the subspecies ithaburensis is characterized by a significantly more severe dry season as the DSWD is 36-180% greater than in the bioclimatic niche of the subspecies macrolepis. It is suggested that the duration and the severity of the dry season is a major limiting factor in the spatial distribution of the subspecies macrolepis. Main conclusionsThe reference to the duration (LDS) and severity (DSWS) of the dry season is essential when defining the bioclimatic niche of Mediterranean species. KeywordsBioclimatic niche, bioclimatic tolerance range, dry season water deficit, extent of occurrence, Mediterranean bioclimate, Tabor oak.

ABSTRACT:Coppicing was widespread throughout Europe for many centuries but was largely abandoned in the second half of the 19 th century. Currently, there has been a renewed interest in coppicing for biomass production and nature conservation.We studied differences in soil chemistry and tree growth between active and abandoned coppices to highlight the impacts of coppice restoration on soil fertility and tree. Stand structure, collected soil samples and tree cores were compared on 46 research plots in temperate Turkey. The plots were set as actively managed and abandoned coppice stand. In our study no effect of coppicing on growth rate was confirmed. Active coppice stands had lower content of Ca, K, N and C:N and higher soil acidification than abandoned coppices. The tree growth rate was significantly higher on more nutrient-rich soils. Coppice restoration may not result in increased biomass production in long-term periods due to a negative effect on soil fertility.

Estructura del glande y de la cúpula de Quercus ithaburensis Decne. subsp. ithaburensis y de Quercus ithaburensis subsp. inacrolepis (Kotschy) Hedge & Yalt.: Diferencias esenciales.Key words. Quercus ithaburensis, taxonomy, morphology, acorn, cupule, Israel, Turkey.Palabras clave. Quercus ithaburensis, taxonomía, morfología, glande, cúpula, Israel, Turquía.

Industrial plantations have substantially reduced the pressure on natural forests. There are approximately 80.000 hectares of industrial plantations, established with fast growing coniferous species, 77.000 hectares of which are maritime pine plantations in Turkey. Furthermore, approximately 16.000 hectares of maritime pine plantations, which amount to about 20 percent of all maritime pine plantations in Turkey, occur in Istanbul. The aim of this study is to determine the silvicultural characterictics and individual tree growth pattern of martimie pine plantations owing in different site-index located in Anatolian (Kanlıca, Byekoz, Sultanbeyli and Şile-Sahilköy) and European (Bahçeköy-Bentler, Arnavutköy and Terkos-Durusu) Istanbul. In order to determine required silvicultural treatments, all the trees' live crown ratios (CR) were calculated and categorized with respect to CR ≤ 0.30, 0.31-0.40 and 41 ≤ CR. The minimum and maximum recorded values for the trees' age, DBH, height and stem volume were found in the range of 22-50 years, 26.6-46.8 cm, 14.0-23.0 m and 0.5150-1.8560 m 3 respectively. The results revealed that sampled trees reached to mean breast height of 1.30 m at the age of 4 years in Kanlıca, Sultanbeyli, Şile-Sahilköy, Terkos-Durusu and Arnavutköy whereas the ones in Beykoz and Bahçeköy-Bentler reached the same height at the age of 3 years. According to these results, tending during the thicket stages of trees within these areas is completed at 3 to 4 years of age. In order to take advantage of the fast growing attributes of maritime pine which was found to grow fast within first 10 years, the first thinning should commence at the age of 11-12 years; thereafter, the second thinning should commence at the age of 18-20 years; finally, the final cut should be performed when the plantation is approximately 30 years of age. If rotation age is considered 40 years, the third thinning should commence at the age of 30 years.Keywords: Growth-increment pattern, fast growing species, industrial plantation, thinning age, live crown ratio. İstanbul Bölgesi'ndeki Sahilçamı (Pinus pinaster) plantasyonlarının silvikültürel yönden incelenmesiÖzet: Odun hammaddesi talebinin, hızlı gelişen türlerle oluşturulan plantasyonlardan karşılanması doğal ormanlarımız üzerindeki baskıyı da azaltacaktır. Türkiye genelinde 80 bin hektarı aşan hızlı gelişen iğne yapraklı tür plantasyonlarının yaklaşık 77 bin hektarı sahilçamı plantasyonlarından oluşmaktadır. Bunun yaklaşık 16 bin hektarı (%20) ise İstanbul Bölgesi'nde bulunmaktadır. Bu çalışmada, Anadolu (Kanlıca, Beykoz, Sultanbeyli ve Şile-Sahilköy) ve Avrupa (Bahçeköy-Bentler, Arnavutköy ve Terkos-Durusu) yakasındaki sahilçamı plantasyonlarının silvikültürel özelliklerinin saptanması ve büyüme performanslarının tek ağaç bazında belirlenmesi amaçlanmıştır. Örnek alanlar için uygulanacak özel silvikültürel tedbirlerin belirlenmesi için bireylerin canlı tepe oranları (TO) hesaplanmış ve TO ≤ 0,30; 0,31-0,40 ve 41 ≤ TO' ya göre kategorize edilmiştir. Örnek ağaçların yaş, g...

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