Behavior of the groundwater in a riverine-type mangrove forest
Behavior of the groundwater in a riverine-type mangrove forest
复制标题
河流型红树林地下水的动态
DOI：
10.1007/s11273-006-9000-z
复制
发表时间：
2006
影响因子：
1.8
通讯作者：
Yoshichika Ikeda
中科院分区：
文献类型：
--
作者：
Yoshihiro Mazda;Yoshichika Ikeda
通过在日本伊里奥莫特岛的野外观测，研究了由潮汐小溪和红树林沼泽组成的河流型红树林中地下水的行为和底层沉积物的物理性质。潮水从沼泽地表面退去到小溪后，到下一次大潮时，小溪附近沼泽地的地下水位下降了15厘米，尽管远离小溪的地点和红树林外的开阔海岸的地下水位下降可以忽略不计。从沼泽排到小溪的地下水的量强烈地取决于潮差和将潮汐小溪与红树林沼泽边缘分开的陡峭堤岸的存在。根据地下水位的下降，估算出该沼泽的整体导水率为1.5×10~(−)~2×10~(-2)cm/S，比实验室利用该沼泽采集的小尺度沉积物岩心测得的导水率大2~3个数量级。这些结果表明，拥挤、复杂和大型动物洞穴以及富含红树林腐殖质的沉积层的存在增加了红树林沼泽的渗透性。此外，红树林地形和潮汐小溪陡峭的岸坡在促进红树林沼泽与邻近近岸水域之间通过地下水进行物质交换方面发挥了重要作用。
The behavior of groundwater and physical properties of bottom sediment in a riverine-type mangrove forest which is composed of a tidal creek and fringing mangrove swamps were investigated through field observations at Iriomote Island, Japan. After the tidal water ebbed from the swamp surface to the creek, groundwater levels at swamp sites near the creek fell by up to 15 cm by the next flood tide, although the fall was negligible at sites far from the creek and at the open coast outside the mangrove forest. The amount of groundwater discharged to the creek from the swamp depended strongly both on the tidal range and the presence of the steep bank which separates the tidal creek from the fringing mangrove swamp. Based on the fall of groundwater level, the bulk hydraulic conductivity of the swamp was estimated to be 1.5×10−2 cm/s. This value is two to three orders of magnitude larger than that measured in a laboratory using small scale sediment core samples collected in the swamp. These results suggest that the presence of crowded, intricate and large animal burrows as well as sediment layers rich in mangrove humus increases permeability in the mangrove swamp. Further, it is suggested that the mangrove topography with the steep bank of the tidal creek plays an important role which enhances material exchanges through groundwater between the mangrove swamp and the adjacent offshore waters.