Konya havzası, Türkiye’de çölleşme eğilimleri ve iklim–bitki örtüsü etkileşimlerinin çok ölçekli uzaktan algılama analizi (2000–2025)

Year 2025, Volume: 14 Issue: 4, 1690 - 1699, 15.10.2025

Ahmet Emin Karkınlı

Abstract

Türkiye'nin önemli bir agro-ekosistemi olan Konya Havzası, çölleşmeye karşı giderek daha savunmasız hale gelmektedir. Bu çalışma, Google Earth Engine platformu kullanılarak 2000 ve 2025 yılları arasındaki bitki örtüsü dinamiklerini ve iklimsel etkenleri değerlendirmektedir. Uzun vadeli eğilimleri haritalamak için MODIS zaman serileri (NDVI ve SAVI) analiz edilmiş ve orta çözünürlüklü Landsat verileriyle bozulma odak noktaları belirlenmiştir. Bulgularımız bir çelişkiyi ortaya koymaktadır; zira havza, özellikle tarım arazilerinde (+0.0042 NDVI birimi/yıl) hafif bir yeşillenme eğilimi gösterirken, Landsat verileri toplam 3471.93 km² alana yayılan bozulma odakları olduğunu göstermektedir. Bu alanların %21.4'ünü tarım arazileri oluşturmakta ve yaklaşık %70'i, yeraltı suyuna dayalı sulamanın en yoğun olduğu 1000 m'nin altındaki rakımlarda meydana gelmektedir. İklimsel etkenler bu dinamiği netleştirmektedir. Anlamlı bir ısınma eğilimi (0.05 °C/yıl; p = 0.0102) tespit edilirken, bitki örtüsü yağışla pozitif korelasyon göstermiş (r = 0.50, p < 0.01) ancak sıcaklıkla anlamlı bir ilişki sergilememiştir (r = 0.09, p = 0.66). Mekansal haritalar, kuzeydeki yağışa bağımlı otlaklarda yağış kontrolünü ve güneydeki sulu tarım ovalarında sıcaklık stresini doğrulamıştır. Bu çok ölçekli yaklaşım, mütevazı bir yeşillenmenin yerel bozulmayla bir arada bulunması nedeniyle havza geneli ortalamalarının yanıltıcı olabileceğini göstermektedir. Bulgular, bu hayati bölgedeki çölleşme risklerini azaltmak için hedefe yönelik arazi ve su yönetimi politikalarına rehberlik edecek mekansal olarak ayrıntılı verilere duyulan ihtiyacı vurgulamaktadır.

Keywords

Çölleşme , Uzaktan algılama , NDVI/SAVI , İklim-vejetasyon ilişkileri , Hotspot analizi

Multi-scale remote sensing of desertification trends and climate–vegetation interactions in the Konya basin, Türkiye (2000–2025)

Abstract

Konya Basin, a key agro-ecosystem in Turkey, is increasingly vulnerable to desertification. This study assesses vegetation dynamics and climatic drivers between 2000 and 2025 using the Google Earth Engine platform. MODIS time-series (NDVI and SAVI) were analyzed to map long-term trends, and medium-resolution Landsat data identified degradation hotspots. Our results reveal an apparent contradiction. The basin shows a subtle greening trend, particularly in croplands (+0.0042 NDVI units yr⁻¹). However, medium-resolution Landsat data simultaneously indicate degradation hotspots covering a total of 3471.93 km². Croplands account for 21.4% of these areas, and about 70% occur below 1000 m, where groundwater-dependent irrigation is most intense. Climatic drivers clarify this dynamic. A significant warming trend of 0.05 °C yr⁻¹ (p = 0.0102) was detected, while vegetation correlated positively with precipitation (r = 0.50, p < 0.01) but showed no significant relationship with temperature (r = 0.09, p = 0.66). Spatial maps confirmed precipitation control in northern rainfed grasslands and temperature stress in irrigated southern plains. This multi-scale approach shows that basin-wide averages can be misleading, as modest greening coexists with local degradation. The findings emphasize the need for spatially explicit data to guide targeted land and water management policies to mitigate desertification risks in this vital region.

Keywords

Desertification , Remote sensing , NDVI/SAVI , Climate-vegetation relationships , Hotspot analysis

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