Çoruh Nehri Havzası’nda Bulunan Veliköy Alt Havzası’nın Yüzey Erozyon Riskinin Belirlenmesi ve Haritalandırılması

Öz

Yeryüzündeki bitki örtüsü, farklı zamansal ve mekânsal ölçeklerde işlevler gören dünya ekosistemlerinin önemli bir parçasıdır. Diğer birçok işlevinin yanı sıra, arazi kullanımı olarak orman ekosistemleri toprak yüzeyini şiddetli yağmurların erosif etkisinden önemli ölçüde koruyarak toprak erozyonu ve su kirliliğini önemli ölçüde azaltırlar. Bu çalışmanın amacı; Türkiye’nin kuzeydoğusunda yer alan Çoruh Nehri Havzası’nda zengin orman kaynaklarına sahip bir alt havza olan Veliköy’ün (417 km²) yüzey erozyon riskini RUSLE yöntemiyle belirlemektir. Bu amaçla, RUSLE denklemini oluşturan bitki örtüsü (C), yağış (R), toprak erodibilitesi (K), yamaç uzunluğu/eğim (LS) ve koruma faaliyeti (P) faktörleri birbirleriyle çarpılarak yüzey erozyonuyla kaybolan toprak miktarı tahmin edilmiştir. Çalışmanın sonunda, bu alt havzadan yüzey erozyonuyla kaybolan toprak miktarı yaklaşık 3.9 t ha^-1 yıl^-1 bulunmuştur. Üretilen toprak kaybı haritaları Veliköy alt havzasının %8.2’sinin erozyon potansiyeli açısından yüksek ve çok yüksek riskli alanlar sınıfına girdiğini göstermiştir. Dolayısıyla, gerçekleştirilecek erozyon kontrol faaliyetleri öncelikli olarak bu alanlarda yoğunlaştırılmalıdır.    

Anahtar Kelimeler

• Veliköy Mikrohavzası,RUSLE,Çoruh Nehri Havzası,Erozyon

Assessing and Mapping Erosion Risk for Velikoy Sub-watershed within Coruh River Basin in Turkey

Öz

Vegetation on earth surface is the integral part of the world ecosystems in functioning for varying spatial and temporal scales. Along with other benefits, land-use as a forest can dramatically reduce the soil erosion and water pollution by protecting the soil surface from erosive effects of rainfall. The objective of this study was to determine rill/interrill (surface) erosion risk by using the RUSLE equation for Velikoy sub-watershed (417 km²) which has rich forest-resources within the Coruh River Basin located at northeastern Turkey. Land use and cover (C factor), rainfall and runoff (R factor), soil erodibility (K factor), slope length and steepness (LS factor), and management support practice (P factor) were identified as the sub-factors for the RUSLE equation and were multiplied to estimate soil loss by rill/interrill erosion. Results showed that the mean surface soil erosion from the sub-watershed was around 3.9 t ha^-1 yr^-1. Of the total study area, 8.2% was estimated as the areas of high and very high risk for the potential surface soil erosion that also indicates prioritization for the implementation of the erosion conservation measures.

Anahtar Kelimeler

• RUSLE,Coruh River Basin,Velikoy Watershed,Surface Water Erosion

Kaynakça

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