Low nitrate retention capacity in calcareous soil under woodland in the karst region of southwestern China. (June 2016)

• Record Type: Journal Article
• Authors: Zhu, Tongbin; Zeng, Siman; Qin, Hanlian; Zhou, Kexin; Yang, Hui; Lan, Funing; Huang, Fen; Cao, Jinhua; Müller, Christoph
• Is Part Of: Soil biology and biochemistry. Volume 97(2016)
• Page Start: 99
• Page End: 101
• Publication Date: 2016-06
• Subjects: Karst -- Calcareous soil -- 15N dilution technique -- Gross nitrogen transformations -- Nitrate retention; Soil biochemistry -- Periodicals; Soil biology -- Periodicals; Sols -- Biochimie -- Périodiques; Sols -- Biologie -- Périodiques; Sols -- Microbiologie -- Périodiques; Bodembiologie; Biochemie; 631.46
• DOI: 10.1016/j.soilbio.2016.03.001
• Languages: English
• ISSNs: 0038-0717

Abstract

Abstract: A 15 N-tracing study was conducted to investigate the gross N transformation rates involved in the production and consumption of NH4 + and NO3 − in karst region soils (a calcareous and a red soil) from southwest China under woodland. The gross mineralization rate of organic N to NH4 + was much lower in calcareous soil (3.71 mg N kg −1 d −1 ) than in red soil (5.57 mg N kg −1 d −1 ), while the total gross nitrification rate was significantly higher in calcareous soil (5.80 mg N kg −1 d −1 ) than in red soil (0.70 mg N kg −1 d −1 ). Microbial NO3 − immobilization accounted for 2.9% and 153% of the total nitrification in calcareous soil and red soils respectively. Thus the calcareous soils in the karst region have a low biological N retention capacity and high N losses, which are further aggravated by the high precipitation and fractured soil structure. Highlights: Calcareous soil and red soil under woodland were chosen in karst region. Gross N transformation rates were studied using 15 N tracing method. Biological inorganic N supply capacity was lower in calcareous soil than red soil. O NH4 significantly increased but I NO3 decreased in calcareous soil. A low biological N retention capacity was observed in calcareous soil.