Freshwater input structures soil properties, vertical accretion, and nutrient accumulation of Georgia and U.S. tidal marshes
Freshwater input structures soil properties, vertical accretion, and nutrient accumulation of Georgia and U.S. tidal marshes
复制标题
DOI：
10.4319/lo.2007.52.3.1220
复制
发表时间：
2007-05-01
影响因子：
4.5
通讯作者：
Craft, Christopher
中科院分区：
文献类型：
--
作者：
Craft, Christopher
为了确定淡水输入与沼泽土壤性质之间的关系，比较了佐治亚州三个不同淡水输入量的河口潮汐沼泽的容重、养分(碳[C]、氮[N]、磷[P])、堆积和积累的测量结果。淡水为主的阿尔塔马哈河沼泽地土壤有机C和N(0-30 cm)是杜博伊湾和萨佩洛河盐碱地的两倍。在淡水为主的沼泽中，CS-137对有机碳和有机氮的积累和积累是盐沼的三到五倍。在佐治亚州沼泽观察到的模式在地理上是一般的；从美国毗邻的61项研究汇编的潮汐淡水和微咸水沼泽土壤的数据显示，无论地理区域如何，都比盐沼的容重更低，有机碳和有机氮的百分比更高。盐度是淡水输入的指标，与土壤有机C和N的百分比以及佐治亚州沼泽地和美国其他毗邻地区的沼泽地的垂直淤积量呈负相关。格鲁吉亚沼泽地上和地下的出苗植物产量与盐度无关，但根的分解速率与盐度呈正相关，与土壤有机C和C积累量呈负相关。在佐治亚州的潮汐沼泽和其他地方，土壤有机质的含量和积累是由淡水通过其分解作用来调节的。
To identify relationships between freshwater input and marsh soil properties, measurements of bulk density, nutrients (carbon [C], nitrogen [N], phosphorus [P]), accretion, and accumulation were compared in tidal marshes of three estuaries of Georgia that varied in delivery of freshwater. Soil organic C and N (0-30 cm) were two times greater in marshes of the freshwater-dominated Altamaha River than in the salt marshes of Doboy Sound and Sapelo River. Cs-137 accretion and accumulation of organic C and N were three to five times greater in freshwater-dominated marshes than in salt marshes. The patterns observed in Georgia marshes were geographically general; data for tidal freshwater and brackish marsh soils compiled from 61 studies in the conterminous United States showed lower bulk density and higher percent organic C and N than salt marshes, regardless of geographic region. Salinity, a proxy for freshwater input, was inversely correlated with percent soil organic C and N and with vertical accretion in Georgia marshes and in marshes elsewhere in the conterminous United States. There was no relationship between above- or belowground emergent plant production and salinity of Georgia marshes but the rate of root decomposition was positively related to salinity, and decomposition rate was negatively related to percent soil organic C and C accumulation. In Georgia tidal marshes and elsewhere, soil organic matter content and accumulation are mediated by freshwater through its effects on decomposition.