NIU Yingquan1,2, LI Jun1*, YANG Xi1, WEI Zhongqing3, ZHANG Yaya1,2, GUO Ying1,2
(1. Tianjin Key Laboratory of Water Environment and Resources, Tianjin Normal University, Tianjin 300387, China;
2. College of Urban and Environment Sciences, Tianjin Normal University, Tianjin 300387, China;
3. Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China)
Abstract: An investigation on composition and distribution of water-soluble carbon and nitrogen in farmlands (n = 4) and wastelands (n = 4) of different salinized soils in Tianjin City, China was carried out. Results show that the soluble organic carbon (SOC) ranges from 26.1～46.4 mg/kg and 19.6～77.8 mg/kg in farmlands and wastelands, respectively. SOC has a trend of drop-rise-stable from topsoil to subsoil. The total soluble nitrogen (TSN), NO3--N and soluble organic nitrogen (SON) in farmlands appear higher than in wastelands, and the average contents in farmlands are 0.84～5.9, 10.8～10.5, and 0.9～8.7 times as in wastelands, respectively. The NO3--N and SON are the main form of TSN, accounting for 38%～72% and 26%～60% of the TSN in the farmlands, and 32%～75% and 16%～58% of the TSN in the wastelands, respectively. The NO3--N and SON are mainly accumulated in topsoil and subsoil in farmland profiles, but mainly in topsoil in wasteland profiles, and have a higher risk of leaching losses in farmlands.
Key words: Tianjin; salinized soil; farmland; wasteland; water-soluble nitrogen
EARTH AND ENVIRONMENT Vol. 44, No.2 Tot No.310, 2016, Page 169-176