tailieunhanh - The effect of compaction on urease enzyme activity, carbon dioxide evaluation and nitrogen mineralisation

The effects of compaction on urease enzyme activity, carbon dioxide evaluation and nitrogen mineralisation of urea-treated and untreated soils were investigated. | Turk J Agric For 24 (2000) 437–441 © TÜBİTAK The Effect of Compaction on Urease Enzyme Activity, Carbon Dioxide Evaluation and Nitrogen Mineralisation Ayten KARACA, Abdullah BARAN, Koray KAKTANIR Ankara University, Faculty of Agriculture, Soil Science Department, Ankara-TURKEY Received: Abstract: The effects of compaction on urease enzyme activity, carbon dioxide evaluation and nitrogen mineralisation of urea-treated and untreated soils were investigated. Soils were compacted at compaction levels of O kgcm-2 , 2 kgcm-2 and 4 kgcm-2 and incubated for 28 days. The changes in urease enzyme activity, CO2 evaluation and nitrogen mineralization were determined during incubation periods. Urease enzyme activity was decreased significantly (). Ancak üre ilave edilen topraklarda toprak sıkışmasının üreaz enzim aktivitesi ve CO2 çıkışı üzerine olan olumsuz etkisi üre ilave edilmeyen topraklara göre daha az bulunmuştur. İnkübasyon süresine bağlı olarak üre ilave edilmiş topraklarda üre ilave edilmemişe göre yaklaşık 5 kat fazla NH4+ -N’u ve 4 kat fazla NO3- -N’u belirlenmiş olup, her iki basınç uygulamasında da nitrifikasyon olayı önemli ölçüde engellenmiştir (P<). Anahtar Sözcükler: Toprak sıkışması, üreaz enzim aktivitesi, karbondioksit çıkışı, azot mineralizasyonu. Introduction Compacting of soil may cause problems by changing the porosity in the soil. Since this has effects on biological activity as well as on the physical properties of the soil, the growth of plants and roots may be negatively influenced (1, 2). Studies concerning aeration characteristics of soil and its effects on growth of plants are mostly concentrated on the composition of air in the soil. The composition of soil air is much different from the of atmospheric air, and its character depends on the biology of the soil. In addition, compacting humidity and soil layer thickness also influence the air content of soil. Many authors have researched air composition in soil to determine