Effects of rye roots and shoots on soil aggregate erosion rate

Çavdar (Secale cereale L) kök ve saplarının parçalanması sonucunda ortama karbon ve azot içeren organik bileşikler bırakılmaktadır. Bu bileşikler ise toprak agregat oluşum ve stabilizasyonuna katkıda bulunmaktadırlar. Farklı büyüklüklerdeki agregatların (2.0 - 4.0, 4.0 - 6.3 ve 6.3 - 9.5 mm) içindeki farklı özelliklere sahip katmanlar son zamanlarda geliştirilen Toprak Agregat Erozyon Çemberleri kullanılarak birbirinden ayrılmıştır. Agregatların dış katmanını ve geçiş katmanını ayırmak için gerekli süre kaydedilerek agregat erozyon oranlan belirlenmiştir. Çavdar yetiştirilen topraklardan alınan agregatların dış yüzeylerinin erozyona dayanıklılıkları kontrol topraklara kıyasla daha fazla bulunmuştur. Sonuç olarak toprakta gelişen aktif bitki köklerinin bulunması, toprak agregatlarının stabilitesini arttırmıştır.

Agregat erozyon oranı üzerine çavdar kök ve saplarının etkileri

Rye (Secale cereale L.) roots and shoots release C and N compounds in situ during their decomposition. Concentric layers of aggregates (2.0 - 4.0, 4.0 - 6.3 and 6.3 - 9.5 mm) were removed by newly designed meso soil aggregate erosion (SAE) chambers.Soil aggregate erosion rates were determined by recording the required time to remove external and transitional layers of aggregates. Soil aggregates sampled from rye cover cropped plots were more resistant to erodobility than those sampled from control plots. Rye roots contributed as much as rye shoots to the soil aggregate stability. Therefore maintaining active plant root in the soil can increase resistance of soil aggregates.

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