Long-Term (1984–2024) Land Surface Temperature (LST) Trends at Iztuzu Beach (Dalyan, Türkiye): A Decadal Analysis

Abstract

Long-term variations in land surface temperature (LST) can significantly influence the ecological functioning of coastal habitats and the reproductive dynamics of species inhabiting these environments. This study examined LST trends at Iztuzu Beach (Dalyan), one of the ecologically critical coastal areas in the Mediterranean basin and a key nesting habitat for the loggerhead sea turtle (Caretta caretta), over the period 1984–2024. Landsat data with 30 m resolution covering May–August were used, comprising 314 satellite images corresponding to 12 decadal periods (early, middle, and late 10-day intervals of each month). Analyses included zonal Ordinary Least Squares (OLS) regression at the regional scale and pixel-level Mann–Kendall tests with Sen’s Slope statistics. Evaluations conducted across 429 stable land pixels revealed positive trends in 9 out of 12 decadal periods. The most pronounced increases occurred in mid-May and late August. Warming trends observed in late August were statistically significant at the 90% confidence level (Sen’s slope ~0.118 °C·yr⁻¹, u = 2.62). Although mid-May exhibited high slope values, high interannual variance limited its spatial significance. Localized warming patterns in the southeastern part of the beach corresponded to areas with intense anthropogenic activity, while notable warming trends were also observed in the central section of the beach. The findings highlight that long-term temperature changes in coastal ecosystems can directly affect habitat integrity and the life cycles of species.

Keywords

• Land surface temperature (LST) trends
• Decadal climate analysis
• Coastal dune thermal dynamics
• Sea turtles nesting habitats
• Iztuzu beach (Dalyan)

Supporting Institution

The author received no financial support for the research, authorship, and/or publication of this article.

Ethical Statement

This study does not involve the use of surveys, interviews, focus group studies, experiments, observations, or human/animal data. Therefore, an ethics committee approval is not required.

İztuzu Plajında (Dalyan, Türkiye) Uzun Dönemli (1984–2024) Yer Yüzey Sıcaklığı (YYS) Eğilimleri: Dekadal Bir Analiz

Abstract

Yer yüzey sıcaklıklarındaki (YYS) uzun dönemli değişimler, kıyı habitatlarının ekolojik işleyişini ve bu alanlarda yaşayan türlerin üreme dinamiklerini önemli ölçüde şekillendirmektedir. Bu çalışma, Akdeniz havzasındaki ekolojik açıdan kritik kıyı alanlarından biri olan İztuzu Plajı’nda (Dalyan), 1984–2024 dönemi boyunca YYS eğilimlerini incelemiştir. Mayıs–Ağustos dönemini kapsayan 30 m çözünürlüklü Landsat verileri kullanılmış; her ayın baş, orta ve son on günlük dilimlerini temsil eden toplam 12 dekada karşılık gelen 314 uydu görüntüsü analiz edilmiştir. Analizlerde bölgesel düzeyde En Küçük Kareler (OLS) regresyonu ile piksel düzeyinde Mann–Kendall testleri ve Sen’s Slope istatistikleri uygulanmıştır. 429 kararlı kara pikseli üzerinde yapılan değerlendirmeler, 12 dekadın 9’unda pozitif eğilimler ortaya koymuştur. Bu artışların en belirgin olduğu dönemler Mayıs’ın ikinci dekadı ve Ağustos’un son dekadı olmuştur. Ağustos sonu dönemindeki eğilimler %90 güven aralığında istatistiksel olarak anlamlı bulunmuştur (Sen’s slope ~0.118 °C·yıl⁻¹, u = 2.62). May II yüksek eğim değerleri göstermiş olsa da, yıllar arası yüksek varyans, mekânsal anlamlılığı sınırlamıştır. Plajın güneydoğusundaki lokal ısınma desenleri yoğun antropojenik faaliyetlerin görüldüğü alanlarla örtüşürken, merkezi kesimde de dikkat çekici ısınma eğilimleri gözlenmiştir. Bulgular, kıyı ekosistemlerinde uzun vadeli sıcaklık değişimlerinin habitat bütünlüğünü ve türlerin yaşam döngülerini doğrudan etkileyebileceğini ortaya koymaktadır.

Keywords

• Yer yüzey sıcaklığı (YYS) eğilimleri
• Dekadal iklim analizi
• Kıyı kumulu termal dinamikleri
• Deniz kaplumbağası yuvalama habitatları
• İztuzu plajı (Dalyan)

Supporting Institution

Yazar, bu makalenin araştırılması, yazarlığı ve/veya yayımlanması için herhangi bir mali destek almamıştır.

Ethical Statement

Bu çalışma; anket, mülakat, odak grup çalışması, deney, gözlem veya insan/ hayvan verisi kullanımını içermemektedir. Bu nedenle etik kurul onay belgesi gerektirmemektedir.

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