Determination of the Runoff and Suspended Sediment from Two Different Slope Length Using Field Plots

Öz

In this study, the effect of slope length on runoff and suspended sediment yield has been investigated by using plots on uniform slopes under natural rainfall conditions. From September 2007 to September 2009, during two year-period, measurements were done in Dallıca village experimental area in Bartın province. In this study, six field plots with a width of 1.87 m were used. Three of them were 5.5 m long (short plots) and remaining three were 11.05 m long (long plots). Plots were located on bare soil surface that has no conservative vegetation. During the period of experimentation, a total of 158 rainy days were registered and average annual rainfall amount was 1194.8 mm. Average annual runoff per square meter was 270.81 mm, and 311.27 mm in long and short plots, respectively. Average annual suspended sediment was 809.68 g m-2, and 766.53 g m-2 from long and short plots, respectively. While statistically significant differences were found in runoff amount from plots with different lengths, there were no statistically significant differences in terms of the amount of eroded sediment.

Anahtar Kelimeler

• Key Words: Slope length
• Runoff
• Suspended sediment
• Field plot
• Rainfall

Farklı Uzunluktaki İki Yamaçtan Oluşan Yüzeysel Akış ve Askıda Sedimentin Parsel Yöntemi Kullanılarak Belirlenmesi

Öz

Bu çalışmada doğal yağış koşulları altında düz eğim şekline sahip yamaçlarda, yamaç uzunluğunun yüzeysel akış ve askıda sediment üretimine etkisi araştırılmıştır. Bartın ili Dallıca köyü içinde yer alan deneme alanında, Eylül 2007 ile Eylül 2009 tarihleri arasında iki yıl süreyle ölçümler yapılmıştır. Çalışmada genişlikleri 1.87 m olan üç tanesi 5.5 m uzunluğunda (kısa parsel), üç tanesi 11.05 m uzunluğunda (uzun parsel), toplam altı adet arazi parseli kullanılmıştır. Parseller, koruyucu bitki örtüsünün olmadığı çıplak arazi yüzeyine tesis edilmiştir. Çalışma süresi boyunca 158 gün yağmurlu olup, düşen yıllık ortalama yağmur miktarı 1194.8 mm olmuştur. Uzun parsellerde metrekareden yıllık ortalama 270.81 mm, kısa parsellerde ise 311.27 mm yüzeysel akış gerçekleşmiştir. Parsellerden taşınan yıllık ortalama askıda sediment miktarı uzun parsellerde 809.68 g m-2, kısa parsellerde ise 766.53 g m-2 olmuştur. Farklı uzunluktaki parsellerden oluşan yüzeysel akış miktarında istatistiksel olarak farklılık bulunurken, taşınan askıda sediment miktarı bakımından istatistiksel anlamda farklılık bulunmamıştır.

Anahtar Kelimeler

• Yamaç uzunluğu
• Yüzeysel akış
• Askıda sediment
• Arazi parseli
• Yağmur

Kaynakça

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