The Extinction Trajectory of the Crimean Juniper (Juniperus excelsa) Species in Central Anatolia Under Global Climate Change

Yıl 2025, Cilt: 21 Sayı: 1, 646 - 672, 30.06.2025

Ahmet Acarer

https://doi.org/10.58816/duzceod.1694206

https://izlik.org/JA89NE99HD

Öz

The Crimean juniper (Juniperus excelsa) species belonging to the Juniperus genus, which is a species native to various harsh environments, exhibits remarkable resilience, especially in droughts. However, due to changing climate conditions on a global scale, Crimean juniper distribution is at a critical junction. This study aims to delineate both the current and potential distribution models of Crimean juniper in the Central Anatolian region. To achieve this, the Maximum Entropy (MaxEnt) modelling approach was employed, incorporating environmental and climatic variables from the Chelsa dataset. The model results identified mean annual air temperature, elevation, precipitation of the driest month, and roughness index as key contributors to the species current distribution. The model demonstrated strong performance, with an AUC of 0.888 for the training dataset and 0.792 for the test dataset, classifying it as a “good model”. In this context, simulations were conducted for the years 2070 and 2100 under three different scenarios (SSP1-2.6, SSP3-7.0, and SSP5-8.5), based on the current distribution map of Crimean juniper. The simulation outcomes indicated that by 2070, the species’ distribution will experience significant decrease and fragmentation, with the potential for near complete disappearance by 2100. In conclusion, this study underscores the detrimental impacts of global climate change on the distribution of Crimean juniper in the Central Anatolian region.

Anahtar Kelimeler

Crimean juniper , Climate change , Geographical distribution , Maximum entropy , Modelling and mapping

İç Anadolu’daki Boylu Ardıç (Juniperus excelsa) Türünün Küresel İklim Değişikliği Altında Yok Oluşa Sürüklenişi

https://izlik.org/JA89NE99HD

Öz

Juniperus cinsine ait olan ve çeşitli zorlu ortamlara özgü bir tür olan Boylu ardıç (Juniperus excelsa) türü, özellikle kuraklıklarda dikkate değer bir dayanıklılık sergilemektedir. Ancak, küresel ölçekte değişen iklim koşulları nedeniyle, Boylu ardıç dağılımı kritik bir durumdadır. Bu çalışma, Orta Anadolu bölgesinde Boylu ardıçın hem mevcut hem de potansiyel dağılım modeli ve haritalanması ortaya koyulması amaçlamaktadır. Bunu başarmak için, Chelsa veri setindeki iklim ve çevresel değişkenlerin modellenmesini sağlayan Maksimum Entropi (MaxEnt) modelleme yaklaşımı kullanılmıştır. Boylu ardıç model sonuçları, ortalama yıllık hava sıcaklığını, yüksekliği, en kurak ayın yağışını ve pürüzlülük indeksini türün mevcut dağılımına önemli katkıda bulunanlar olarak belirlemiştir. Model, eğitim veri seti için 0,888 ve test veri seti için 0,792’lik bir AUC ile güçlü bir performans göstererek onu “iyi bir model” olarak sınıflandırmıştır. Bu bağlamda, Boylu ardıçın güncel dağılım haritasına dayanarak, üç farklı senaryo (SSP1-2.6, SSP3-7.0 ve SSP5-8.5) altında 2070 ve 2100 yılları için simülasyonlar yürütülmüştür. Simülasyon sonuçları, türün dağılımının 2070 yılına kadar önemli ölçüde azalacağını ve parçalanacağını, 2100 yılına kadar ise neredeyse tamamen yok olma potansiyeline sahip olduğunu göstermiştir. Sonuç olarak, bu çalışma küresel iklim değişikliğinin Orta Anadolu bölgesinde Kırım ardıcının dağılımı üzerindeki olumsuz etkilerini vurgulamaktadır.

Anahtar Kelimeler

Boylu ardıç , İklim değişikliği , Coğrafi dağılım , Maksimum entropi , Modelleme ve haritalama

Kaynakça

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