Nitrogen mineralisation in the soils of alpine mat communities: An incubation experiment under laboratory conditions

Plantago holosteum Scop. and P. atrata Hoppe plant communities contribute to the vegetation mosaic in the humid places on different substrata in the sub-alpine and alpine belts of Uludag Mountain, Bursa, Turkey. Nitrogen mineralisation in the soils of these 2 mat communities was investigated under controlled conditions (60% WHC, 20 °C). | Turk J Bot 31 (2007) 277-286 © TÜB‹TAK Research Article Nitrogen Mineralisation in the Soils of Alpine Mat Communities: An Incubation Experiment under Laboratory Conditions 1, 2 1 Gürcan GÜLERYÜZ *, Serap KIRMIZI , Hülya ARSLAN 1 Uluda¤ University, Faculty of Arts and Science, Department of Biology, Görükle 16059 Bursa - TURKEY 2 Uluda¤ University, Gemlik As›m Kocab›y›k Graduate Vocational School, Gemlik, 16600 Bursa - TURKEY Received: Accepted: Abstract: Plantago holosteum Scop. and P. atrata Hoppe plant communities contribute to the vegetation mosaic in the humid places on different substrata in the sub-alpine and alpine belts of Uluda¤ Mountain, Bursa, Turkey. Nitrogen mineralisation in the soils of these 2 mat communities was investigated under controlled conditions (60% WHC, 20 °C). Different N mineralisation rates in the soils of the communities were found. This difference was clearer in the upper layer (0-5 cm) of soil, in which the organic matter accumulation was high. We found that nitrification occurred in the soils of both communities, but it was dominant in the soils of the P. atrata Hoppe mat community. Our results support the general opinion that plant diversity and composition exert control over N cycling, affecting inorganic N in soils. Key Words: Mat community, grassland, N mineralisation, nitrification, alpine Alpin Keçemsi Topluluklar›n Topra¤›nda Azot Mineralleflmesi: Laboratuar Koflullar›nda ‹nkübasyon Denemesi Özet: Plantago holosteum Scop. ve P. atrata Hoppe bitki topluluklar› Uluda¤’›n subalpin ve alpin kufla¤›ndaki farkl› ana materyeller üzerindeki nemli alanlarda vejetasyon mozai¤ine kat›lmaktad›rlar. Bu iki keçemsi bitki toplulu¤unun topra¤›nda azot mineralleflmesi kontrollü koflullarda (% 60 Maksimum Su Tutma Kapasitesi ve 20 °C) araflt›r›ld›. Toplululuklar›n topraklar›ndaki farkl› azot mineralleflme oranlar› saptand›. Bu farkl›l›k, organik maddenin birikiminin yüksek oldu¤u üst toprak katman›nda (0-5 cm) .