GEOGRAPHICAL RESEARCH ›› 2009, Vol. 28 ›› Issue (1): 118-128.doi: 10.11821/yj2009010014

• Environment and Ecology • Previous Articles     Next Articles

Litter decomposition and nutrient dynamics in different tidal water submergence environments of estuarine tidal wetland

TONG Chuan, LIU Bai-gui   

  1. Research Centre of Wetlands in Sub-tropical Regions, Key Laboratory of Humid Sub-tropical Eco-geo Process of Fujian Universities, School of Geographical Sciences, Fujian Normal University, Fuzhou 350007, China
  • Received:2008-06-20 Revised:2008-09-16 Published:2010-11-20
  • Supported by:

    国家自然科学基金项目(40671174); 福建省自然科学基金资助项目(2006J0128);福建省自然地理学重点学科项目资助

Abstract:

Decomposition of litter plays an important role in carbon turnover and nutrients cycling in wetland ecosystem. Tide is the key feature for the estuarine tidal wetland. The wetlands of the Minjiang River estuary region are one of the major estuarine tidal wetlands in the southeast of China, and the Shanyutan is the largest wetland in the Minjiang River estuary region. Litter decomposition, nutrient dynamics and influencing factors of two native species (Phragmites australis and Cyperus malaccensis) and one exotic invasive species (Phragmites australis) were studied using mesh bag method in two sites under different tidal water submergence conditions. One site was near the tide ditch, and the other is far from the tide ditch in central Shanyutan wetland. The results indicated that: (1) Frequent tidal water submergence had no significant effects on the litter decomposition rates of three plants. (2) Frequent tidal water submergence accelerated the N and P loss of Cyperus malaccensis and Spartina alterniflora, however, it had little effect on Phragmites australis. (3) The order of litter decomposition rate was Cyperus malaccensisSpartina alternifloraPhragmites australis, with rates of 0.003166-0.005280 d 1, and the time of 95% dry mass of litter loss ranged from 1.56 to 2.61a. (4) C concentrations had only a little change, and the major pathway of C release was mineralization during the 280 days; there was an upward trend in N concentrations, at the end of the experiment, N content had a net loss and the major pathway of loss was mineralization; there was an obvious fluctuating downward trend in P concentrations at the end of the experiment, P content had also a net loss and leaching losses were responsible for much of P loss. (5) Litter quality was a main factor influencing the litter decomposition rates of the three plants. Litter decomposition rate of Cyperus malaccensis with the lowest C/P was the greatest.

Key words: litter decomposition, nutrient dynamics, tidal water, Phragmites australis, Cyperus malaccensis, Spartina alterniflora, Minjiang River estuary