YENİDEN TAHSİS VE DAYANIKLILIK BAĞLAMINDA DEPREMLERİN TEDARİK ZİNCİRİNE STRES TESTİ ETKİLERİ: TÜRKİYE ÖRNEĞİ

Öz

Bu çalışma, büyük ölçekli depremlerin bölgesel tedarik zinciri ağları üzerindeki aksama, yeniden yönlenme ve toparlanma dinamiklerini incelemektedir. 2010–2023 dönemini kapsayan aylık panel veri seti (n = 4.368 bölge-ay) kullanılarak, Türkiye’deki 26 NUTS-2 bölgesine ait yük akış verileri mekânsal deprem maruziyeti ölçüleriyle birleştirilmiştir. Yöntemsel olarak, deprem şoklarının bölgeler arasındaki yarı-dışsal mekânsal ve zamansal varyasyonundan yararlanan panel farkların farkı yaklaşımı uygulanmış; bölge ve ay sabit etkileri ile zamana bağlı kontroller modele dâhil edilmiştir. Tanımlama stratejisi, stacked difference-in-differences spesifikasyonları ve müdahale öncesi eğilimleri sınayan olay-çalışması analizleriyle güçlendirilmiştir. Ağ içi yeniden yönlenme tepkileri, aynı bölgesel düzeyde oluşturulan trafik temelli göstergelerle ölçülmüştür. Bulgular, deprem şoklarının yük hacimlerinde ani düşüşlere ve heterojen toparlanma patikalarına yol açtığını göstermektedir. Toparlanma hızını belirleyen temel unsur altyapı yoğunluğu değil; yeniden yönlendirmeyi mümkün kılan mod çeşitliliği ve ağ yedekliliğidir. Sonuçlar, lojistik dayanıklılığın altyapı kalitesinden ziyade sistemin yapısal çeşitliliğine dayandığını ortaya koymaktadır.

Anahtar Kelimeler

• Yük taşımacılığı
• Ağ Tahsisi
• Bölgesel Lojistik
• Deprem etkileri

EARTHQUAKES AS SUPPLY CHAIN STRESS TESTS WITH NETWORK DISRUPTION, REALLOCATION, AND RESILIENCE EVIDENCE FROM TÜRKİYE

Öz

This study examines how large-scale earthquakes function as stress tests for regional supply chain networks by revealing disruption, reallocation, and recovery dynamics in freight transportation systems. Using a monthly panel dataset covering 2010–2023 (n = 4,368 region-month observations), the paper combines freight flow statistics across 26 NUTS-2 regions in Türkiye with spatial measures of earthquake exposure. Methodologically, we implement a panel difference-in-differences design that exploits the quasi-exogenous spatial and temporal variation of seismic shocks across regions, with region and month fixed effects and time-varying economic controls. The identification strategy is further strengthened through stacked difference-in-differences specifications and event-study analyses that test pre-treatment trends and trace dynamic post-shock adjustment. Network reallocation responses are captured via traffic-based indicators constructed at the same regional aggregation level. The results show that earthquake shocks generate sharp and immediate declines in freight volumes, followed by heterogeneous recovery trajectories across regions. Crucially, recovery speed is not primarily driven by infrastructure density, but by pre-existing modal diversity and network redundancy, which facilitate rerouting under capacity constraints. These findings suggest that resilience in logistics networks emerges less from infrastructure quality alone and more from structural diversity embedded in the system. The study contributes to the empirical supply chain literature by providing causal, network-aware evidence from a real-world shock environment.

Anahtar Kelimeler

• Supply chain robustness
• Earthquake impacts
• Freight transportation
• Network reallocation
• Regional Logistics

Kaynakça

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