JOURNAL OF NANJING FORESTRY UNIVERSITY ›› 2016, Vol. 59 ›› Issue (06): 20-26.doi: 10.3969/j.issn.1000-2006.2016.06.004

Previous Articles     Next Articles

Effects of soil fauna on seasonal variations of soil N mineralization under different land use type

ZHANG Wenwen1,2, XIAO Hanran1, YANG Baoling1,3, DONG Kejia1, RUAN Honghua1*, ZHENG Abao1,4,SHEN Caiqin5, CAO Guohua5   

  1. 1.Co-Innovation Center for Sustainable Forestry in Southern China, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China;
    2.Shanghai Forestry Station, Shanghai 200072, China;
    3. Jiangsu Polytechnic College of Agriculture and Forestry, Jurong 212400,China;
    4. Jiangsu Province Administration of Forestry, Nanjing 210036, China;
    5. Forest Farm of Dongtai City, Dongtai 224200, China
  • Online:2016-12-18 Published:2016-12-18

Abstract: A field experiment was conducted under three different land use types(i.e. poplar plantation, cropland and crop-poplar integrated system)with three treatments including control, nematodes exclusion and soil fauna exclusion in a coastal area of northern Jiangsu. By application closed-up incubation method, the seasonal variations of soil mineral N and net N mineralization rate were analyzed. The results showed that the contents of NH+4-N,NO-3-N,TMN had significant seasonal variations under three land uses types(P<0.05), nematodes and soil fauna exclusions decreased the contents of NH+4-N,NO-3-N and TMN in four seasons, but did not alter their seasonal variation trends. The seasonal variation of NH+4-N under three land uses types all showed summer>autumn>spring>winter; seasonal variation of NO-3-N and TMN showed summer>autumn>spring>winter under poplar plantation and crop-poplar integrated system while autumn>summer >spring>winter in cropland. In all sites, soil net N mineralization rates showed significant seasonal dynamic(P<0.05). Maximum soil net N mineralization rate both under poplar plantation and cropland appeared in autumn(0.25 mg/(kg·d), 0.29 mg/(kg·d), respectively), but in crop-poplar integrated system, the maximum soil net N mineralization rate appeared in summer(0.45 mg/(kg·d)). Nematode and soil fauna exclusion all could lower the net N mineralization rates of three land use types in spring, summer and autumn, while did not alter the net N mineralization rates under crop-poplar integrated system, but soil fauna exclusion affected the seasonal dynamics of net N mineralization rates under the poplar plantation and cropland. The net N mineralization rates under poplar plantation and cropland showed summer>autumn>spring>winter with soil fauna exclusion, while autumn>summer>spring>winter with control. Analysis of variance for repeated measurement showed that there were significant interaction effects between sampling times and soil fauna treatments(P<0.01), indicating that soil fauna may affect the seasonal variations of net N mineralization rates.

CLC Number: