中国地理科学(英文版) ›› 2012, Vol. 22 ›› Issue (1): 15-28.

• 论文 • 上一篇    下一篇

Nitrogen Biological Cycle Characteristics of Seepweed (Suaeda salsa) Wetland in Intertidal Zone of Huanghe (Yellow) River Estuary

SUN Zhigao1,MOU Xiaojie2,SUN Jingkuan3,et al.4   

  1. 1. 1. Shandong Key Laboratory for Eco-Environmental Science of Yellow River Delta, Coastal Wetland Ecological Research Base of Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Binzhou 256603, China; Shandong Provincial Key Laboratory of Coastal Zone Environmental
    2. 1. Shandong Key Laboratory for Eco-Environmental Science of Yellow River Delta, Coastal Wetland Ecological Research Base of ;Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Binzhou 256603, China; Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences,
    3. Shandong Key Laboratory for Eco-Environmental Science of Yellow River Delta, Coastal Wetland Ecological Research Base of Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Binzhou 256603, China;
    4.
  • 收稿日期:2010-12-02 修回日期:2011-04-19 出版日期:2012-01-03 发布日期:2011-01-16
  • 通讯作者: MOU Xiaojie E-mail:xjmou@163.com
  • 基金资助:

    国家自然科学基金项目;山东省自然科学基金重点项目;中国科学院“优秀博士学位论文、院长奖获得者”科研启动基金项目

Nitrogen Biological Cycle Characteristics of Seepweed (Suaeda salsa) Wetland in Intertidal Zone of Huanghe (Yellow) River Estuary

  • Received:2010-12-02 Revised:2011-04-19 Online:2012-01-03 Published:2011-01-16
  • Supported by:

    National Natural Science Foundation of China

摘要:

From April 2008 to November 2009, the nitrogen (N) cycle of plant-soil system in seepweed (Suaeda salsa) wetland in the intertidal zone of the Huanghe (Yellow) River estuary was studied. Results showed that soil N had significant seasonal fluctuations and vertical distribution, and the net N mineralization rates in topsoil were significantly different in growing season (p < 0.01). The N/P ratio (9.87 ± 1.23) of S. salsa was less than 14, indicating that plant growth was limited by N. The N accumulated in S. salsa litter at all times during decomposition, which was ascribed to the N immobilization by microbes from the environment. Soil organic N was the main N stock of plant-soil system, accounting for 97.35% of the total N stock. The N absorption and utilization coefficients of S. salsa were very low (0.0145 and 0.3844, respectively), while the N cycle coefficient was high (0.7108). The results of the N turnovers among compartments of S. salsa wetland showed that the N uptake amount of aboveground part and root were 7.764 g/m2and 4.332 g/m2, respectively. The N translocation amounts from aboveground part to root and from root to soil were 3.881 g/m2 and 0.626 g/m2, respectively. The N translocation amount from aboveground living body to litter was 3.883 g/m2, the annual N return amount from litter to soil was more than 0.125(–) g/m2 (minus represented immobili-zation), and the net N mineralization amount in topsoil (0–15 cm) in growing season was 1.190 g/m2. The assessment of N biological cycle status of S. salsa wetland indicated that N was a very important limiting factor and the ecosystem was situated in unstable and vulnerable status. The S. salsa was seemingly well adapted to the low-nutrient status and vulnerable habitat, and the N quantitative relationships determined in the compartment model might provide scientific base for us to reveal the special adaptive strategy of S. salsa to the vulnerable habitat in the following studies.

关键词: compartment model, nitrogen cycling, Suaeda salsa wetland, Yellow River estuary

Abstract:

Abstract: From April 2008 to November 2009, the nitrogen (N) cycling of plant-soil system in Suaeda salsa wetland in the intertidal zone of the Yellow River estuary was studied with a compartment model. Results showed that the N in soil had significantly seasonal fluctuations and vertical distribution, and the net N mineralization rates in topsoil were significantly different in growing season (p<0.01). The N contents in root and stem of S. salsa generally decreased, while those in leaf fluctuated significantly. The N/P ratio (9.87±1.23) of S. salsa was less than 14, indicating that the growth of plant was limited by N. The litter production and the N content in litter changed significantly, and the change trends were just the opposite. The mass loss and N content increased at all times during litter decomposition, and the C/N ratio controlled the N dynamics of S. salsa litter. The N accumulated in S. salsa litter at all times, which was ascribed to the N immobilization by microbes from the decomposition environment. The N in the plant subsystem was mainly stored in aboveground living body. Soil organic N was the main N stock of plant-soil system, accounting for 97.35% of the total N stock. The N absorption and utilization coefficients of S. salsa were very low (0.0145 and 0.3844, respectively), while the N cycling coefficient was high (0.7108). The N turnovers among compartments of S. salsa wetland showed that the N uptake amount of aboveground part and root were 7.764 and 4.332g/m2, respectively. The N translocation amounts from aboveground part to root and from root to soil were 3.881 and 0.626g/m2, respectively. The N translocation amount from aboveground living body to litter was 3.883g/m2, the annual N return amount from litter to soil was larger than 0.125(-)g/m2 (minus expressed immobilization), and the net N mineralization amount in topsoil (0-15cm) in growing season was 1.190g/m2. The assessment of N cycling status of S. salsa wetland indicated that the N was a very important limiting factor, and the ecosystem was situated in unstable and vulnerable status. The S. salsa seemed to be well adapted to the low-nutrient status and vulnerable habitat, and the N quantitative relationships in the compartment model might provide some scientific bases for us to reveal the special adaptive strategy of S. salsa to the vulnerable habitat in the following studies.

Key words: compartment model, nitrogen cycling, Suaeda salsa wetland, Yellow River estuary