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Yayın Afforestation of arid and semiarid ecosystems in Turkey(Tubitak Scientific & Technical Research Council Turkey, 2017-05-28) Çalışkan, Servet; Boydak, MelihSustainable management of arid and semiarid forests requires careful planning and implementation. Afforestation by planting and seeding is a fundamental tool for the establishment of new forests on barren landscapes and restoration of degraded forests in arid and semiarid ecosystems. In afforestation efforts, the consideration of site preparation, selection of species, seed source, and planting methods pose a number of ecological and economic challenges. Possessing one of the world's richest floras, Turkey suffered from heavy degradation during the last millennia. Some studies suggested that forests and steppes once covered 60%-70% and 10%-15% of the Anatolian landscape, respectively. Growing population, overgrazing, clearance for agriculture, fires, excessive timber harvesting, and misuse of lands led to a 26% reduction in the forest area. The Turkish Forest Service completed 2.3 million ha of afforestation and 1.2 ha of erosion control works, mostly in semiarid landscapes. This article presents an assessment of afforestation activities in the semiarid and arid regions of Turkey and is a review of the efforts exerted during the period 1945 to 2014.Yayın A new subspecies of Phoenix theophrasti Greuter (Phoenix theophrasti Greuter subsp. golkoyana Boydak) from Turkey(Istanbul Univ-Cerrahpasa, 2019-07) Boydak, MelihIn the present study, a new subspecies (Phoenix theophrasti Greuter subsp. golkoyana Boydak) is described in Turkey. The unidentified Phoenix taxon native to Bodrum-Golkoy, Aegean Turkey and named as the "Golkoy Phoenix population" has been known to Golkoy's inhabitants for centuries. The Golkoy Phoenix population was considered to be representative of P. theophrasti. Boydak made the first of a number of trips to Golkoy and immediately noticed some distinct differences between the Golkoy Phoenix population, P. theophrasti Greuter, and Phoenix dactylifera L in the early summer of 1990. He continued his investigations on this taxon for many years to shed light on the subject. He made two new trips to the three native stands of P. theophrasti and the Golkoy Phoenix populations in 2015 and 2018. Measurements and observations were made on the morphological characteristics that showed distinct differences among the Golkoy Phoenix population, P. theophrasti, and P. dactylifera. These were related to the length of male stalks and female inflorescences and some fruit and seed characteristics. The results indicate that some distinctive morphological characteristics of the "Golkoy Phoenix population" merit its being described as a new subspecies. "Phoenix theophrasti Greuter subsp. golkoyana Boydak" differs from P. theophrasti Greuter with respect to its longer fruiting-female stalk length and longer male stalk length, its fruiting stalks hold fruits marginally higher, and its having seeds with slightly visible striate surface crust structures and deeper-wider grooves.Yayın Effects of heat shock on seed germination of Turkish red pine (Pinus brutia)(Universidad Austral De Chile, 2016) Boydak, Melih; Çalışkan, ServetFire plays an important ecological role in Mediterranean-type ecosystems. Many Mediterranean plant species exhibit enhanced germination capacity when exposed to heat. In the present study, the effect of high temperatures and exposure times on germination of Turkish red pine (Pinus brutia) was analyzed in order to reveal the response of seeds to fire and the implications on species regeneration. Seeds were heated to a range of temperatures (from 75 to 170 ºC) and exposure times (from 30 seconds to 30 minutes) similar to those obtained in surface soil layers during natural fires. In total, twenty treatments were performed. Seed germination percentages and germination values were calculated for each treatment. The results of ANOVA performed for germination values showed that temperature had a significant effect. Germination percentages increased in thermal treatments at 70 ºC for 10, 15, 20, 25, and 30 min; at 105 ºC for 10, 15, 20, and 25 min, and at 130 ºC for 1 and 2 min. The increase in both temperature and exposure times generally decreased the germination percentage especially at 130 °C and over in comparison with the control. Maximum germination percentage was reached in the treatment at 130 ºC for 1 min while the minimum germination was reached at 130 ºC for 10 min.Yayın Isıtma işleminin kızılçam (Pinus brutia Ten.) tohumlarının çimlenmesine etkisi(Düzce Üniversitesi, 2013-03-01) Çetin, Bilal; Boydak, MelihBu çalışmada, Anamur ve Mersin yörelerinden seçilen 2 kesitteki 4’er yükselti kuşağından (0-400 m, 400-800 m, 800-1200 m ve ≥1200 m) toplanan kızılçam (Pinus brutia Ten.) tohumlarına ısıtma işlemi (1, 3, 5 ve 7 dakika) uygulanmış ve bu tohumların çimlenme özelliklerindeki değişim irdelenmiştir. Araştırmada, ısıtma işlemi uygulanan tohumların hangi sıcaklıkta çimlendirileceğini tespit etmek amacıyla 15, 20 ve 25oC ön çimlendirme testleri yapılmış ve sırasıyla %44,2, %68,1 ve %52,0 çimlenme yüzdeleri elde edilmiştir. Bu çimlendirmelerde en yüksek çimlenmeler her iki kesitte ve bütün yükselti kuşaklarında 20oC’de (%68,1) olmuş ve ısıtma işlemi uygulanan tohumlarda bu sıcaklıkta çimlendirilmiştir. Yapılan çimlendirme denemelerine göre, yükseltinin artmasıyla çimlenme performansları düşmüştür. Isıtılan tohumlarda çimlenme yüzdeleri, genel olarak alt yükselti kuşağından üst yükselti kuşağına doğru azalmıştır. 150oC’de ısıtılan tüm tohumlarda 1 dakika ısıtma süresinde (%62,9) kontrole (%66,4) yakın çimlenmeler hatta bazı yükselti kuşaklarında kontrolden daha fazla çimlenme elde edilmiştir. 3 dakika ısıtma süresindeki (%33,9) çimlenmelerde önemli oranda düşüşler olmuş ve 5 dakikalık ısıtma süresinde (%3,3) ise az miktarlarda çimlenme gözlenmiştir. 7 dakika ısıtma süresinde, bütün yükselti kuşaklarında tohumlar tamamen canlılığını kaybetmiş ve hiç çimlenme (%0,0) olmamıştır.
