MODELLING STUDY ON SUBSURFACE FLOWS AFFECTED BY MACRO-PORES IN MARSH SEDIMENTS
Recent hydrological research on salt marshes based on mathematical models has suggested links of tidally driven pore water flows with both soil aeration rates and plant vegetation patterns, demonstrating the importance of subsurface flows in the salt marsh ecology. Macro-pores, such as crab burrows are typically distributed in marsh sediments, but little attention has been paid to their potential effects on pore water flows in the marsh soil. In this paper, we present the first 3-D model for simulating pore water flows affected by crab burrows. High hydraulic conductivity zones were used to simulate the burrows. We will also discuss the effects of soil compressibility and varying total stress induced by tidal fluctuations. The simulation results show that crab burrows distributed in an upper soil layer can act as water collectors as long as the lower soils is more hydraulically conductive than the overlying soil layer. During the ebb tide, crab burrows collect pore water in the upper soil layer and discharge it into the lower layer. Such a mechanism may enhance pore water exchange between the mash soil and tidal creek, improve soil aeration conditions and increase material exchange between the marsh and coastal water.
macro-pore crab burrow pore water flow salt marsh numerical modelling
Pei Xin Guangqiu Jin Ling Li
Centre for Eeo-Environment Modeling, Hohai University, Nanjing, China Centre for Eco-Environment Modeling, Hohai University, Nanjing,China School of Engineering, The University of Queensland, Queensland, Austrafia
国际会议
第16届亚太地区国际水利学大会暨第3届水工水力学国际研讨会(16th IAHR-APD Congress and 3rd Symoposium of IAHR-ISHS)
南京
英文
1394-1400
2008-10-20（万方平台首次上网日期，不代表论文的发表时间）