九龙江口红树林与毗邻水域营养盐和有机碳的潮水交换

Abstract

红树林缓解近海富营养化、维持近海生物多样性的功能已成共识,但此功能的大小却鲜有报道.在福建九龙江河口,对红树林与其毗邻水域通过潮汐的物质交换进行了定量研究.结果表明:通过潮汐的作用,九龙江口红树林具有吸收毗邻水域氮、磷营养盐的作用,溶解无机氮(dIn)和溶解无机磷(dIP)的吸收量分别为-0.40和-0.04kg/(HM2·d);具有向毗邻水域输出有机碳的作用,溶解有机碳(dOC)和颗粒有机碳(POC)的输出量分别为0.07和0.01kg/(HM2·d).因此,九龙江口红树林是近海水域无机营养盐的汇、有机碳的源.

Although mangrove functions in alleviating eutrophication and maintaining biodiversity in coastal waters were known,few reports were found on the quantities of these functions.Material exchanges between mangrove forest and its adjacent water are helpful in quantifying these important functions.Through differences in contents of NP nutrients and organic carbon between in-forest and out-forest tidal waters,we estimated the exchanges of these materials in Jiulongjiang Estuary.Results showed that through tidal actions,mangrove forest(1)could absorb nitrogen and phosphorus nutrients from its adjacent water area,with dissolved inorganic nitrogen(DIN)and dissolved inorganic phosphorus(DIP)fluxes of-0.40and-0.04kg/(hm2·d),respectively;(2)could export dissolved organic carbon(DOC)and particular organic carbon(POC)to its adjacent water area,with the fluxes of 0.07and 0.01kg/(hm2·d),respectively.Therefore,mangrove forest in Jiulongjiang Estuary is the sink of inorganic nutrients and the source of organic carbon for coastal waters.