Biyoindikatör Organizmalar Olarak Amfibiler ve Sürüngenler: Ekotoksikolojik ve Ekolojik Bir Derleme

Abstract

Amfibiler ve sürüngenler, kendilerine özgü fizyolojik ve ekolojik özellikleri sayesinde çevresel kirliliğin ve ekosistem sağlığının değerlendirilmesinde son derece etkili biyoindikatör organizmalar olarak giderek daha fazla önem kazanmaktadır. Bu derleme, herpetofaunanın biyoizleme çalışmalarındaki kullanımına ilişkin biyolojik, ekolojik ve metodolojik temelleri kapsamlı ve bütüncül bir yaklaşımla değerlendirmektedir. Özellikle bu organizmaların çift yaşam ortamına sahip olmaları, kirletici biriktirme kapasiteleri ve hem akut hem de kronik çevresel stres faktörlerine karşı yüksek duyarlılıkları vurgulanmaktadır. Çalışmada, biyobelirteç yanıtları; biyokimyasal, moleküler, histopatolojik ve davranışsal düzeylerde ele alınarak çok katmanlı bir analiz sunulmuştur. Pestisitler, ağır metaller, endokrin bozucu maddeler ve mikroplastikler gibi başlıca kirletici grupların etkileri; maruziyet yolları ve türlere özgü yanıtlar bağlamında kritik olarak incelenmiştir. Ayrıca amfibilerin erken uyarı sistemi olarak, sürüngenlerin ise uzun vadeli kirletici birikim göstergesi olarak oynadığı roller karşılaştırmalı biçimde değerlendirilmiş ve bu iki grubun birlikte kullanımının önemi ortaya konmuştur. Biyobelirteç temelli yöntemler, genetik analizler ve yeni nesil omik yaklaşımlar; duyarlılık, uygulanabilirlik ve sınırlılıkları açısından ele alınmıştır. Bunun yanı sıra, alandaki temel sorunlar olan standardizasyon eksikliği, türler arası değişkenlik ve uzun dönemli veri ihtiyacı da tartışılmıştır. Son olarak, Türkiye’nin zengin herpetofaunası temel alınarak ulusal biyoizleme programlarının geliştirilmesine yönelik bir çerçeve önerilmiştir. Tür seçimi, örnekleme stratejileri ve biyobelirteç uygulamalarının entegrasyonu ile bu çalışma, ekotoksikolojik izleme çalışmalarının geliştirilmesine ve bilim temelli çevre yönetimi ile koruma politikalarına katkı sağlamayı amaçlamaktadır.

Keywords

• Biyoindikatör
• amfibiler
• sürüngenler
• ekotoksikoloji
• biyobelirteçler
• çevre izleme
• ağır metaller
• pestisitler

Amphibians and Reptiles as Bioindicator Organisms: An Ecotoxicological and Ecological Review

Abstract

Amphibians and reptiles are increasingly recognized as highly effective bioindicator organisms for assessing environmental pollution and ecosystem health due to their unique physiological and ecological characteristics. This review provides a comprehensive and integrative evaluation of the biological, ecological, and methodological foundations underlying the use of herpetofauna in biomonitoring studies. Particular emphasis is placed on their dual habitat utilization, pollutant accumulation capacity, and sensitivity to both acute and chronic environmental stressors. The review synthesizes current knowledge on biomarker responses at multiple levels of biological organization, including biochemical, molecular, histopathological, and behavioral endpoints. The effects of major contaminant groups—such as pesticides, heavy metals, endocrine-disrupting compounds, and emerging pollutants like microplastics—are critically examined in relation to exposure pathways and species-specific responses. In addition, the role of amphibians as early-warning indicators and reptiles as long-term accumulation monitors is comparatively analyzed, highlighting their complementary value in integrated monitoring frameworks. Methodological approaches, including multi-biomarker strategies, genetic assays, and emerging omics-based techniques, are evaluated in terms of sensitivity, applicability, and limitations. The review also addresses key challenges in the field, such as the lack of standardization, variability among species and environments, and the need for long-term datasets. Finally, the study proposes a framework for the development of national biomonitoring programs with particular reference to the diverse and ecologically significant herpetofauna of Turkey. By integrating species selection, sampling design, and biomarker application, this review aims to contribute to the advancement of ecotoxicological monitoring and to support evidence-based environmental management and conservation policies.

Keywords

• Bioindicator
• amphibians
• reptiles
• ecotoxicology
• biomarkers
• environmental monitoring
• heavy metals
• pesticides

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