摘要
生物入侵的生态影响是入侵生态学的一个重要研究领域,但是,目前对于外来植物入侵造成的生态后果评价多集中在对于生态系统地上部分的影响,对于地下生态过程和生物地球化学过程的影响研究则相对较少。利用平衡式孔隙水采样器采集闽江河口鳝鱼滩土著种短叶茳芏(Cyperus malaccensis)沼泽和入侵种互花米草(Spartina alterniflora)沼泽高分辨率的原位土壤间隙水样,测定其营养盐含量。结果表明,短叶茳芏沼泽和互花米草沼泽土壤间隙水中营养盐含量都具有明显的季节变化,尤其是夏季与秋季的差异较大。短叶茳芏沼泽土壤间隙水中,PO43-—P含量随着剖面深度的增加而呈上升的趋势最为明显;溶解无机氮以NH4+—N为主,含量范围为35～200μmol/L;NO2-—N和NO3-—N含量总和在3～10μmol/L之间,其中NO3-—N含量占绝对优势。与短叶茳芏沼泽相比,互花米草沼泽间隙水中铵盐比例较高,氮磷比值较低。以上结果表明,互花米草入侵已对闽江河口鳝鱼滩土著种短叶茳芏沼泽土壤间隙水营养盐循环产生了一定的影响。
The Shanyutan wetlands is the largest tidal wetland located in the mouth of the Min River Estuary,south-east China.In its middle-west part,the native marsh species Cyperus malaccensis dominates the intertidal zone.In recent years,Spartina alterniflora has invaded patches in the Cyperus malaccensis dominated marsh zone.In order to understand the influence of the invasion of Spartina alterniflora on the soil nutrients in porewater of the native species marshes in the Min River Estuary,we chose Cyperus malaccensis marsh and Spartina alterniflo ra marsh to analyze the profiles characters of nutrient concentrations in soil porewater.Soil porewater samples were collected using the pore water equilibrators （peepers） in March,June and September,2010.The results indicated that there were distinct seasonal variations of nutrient concentrations in porewater in both marshes,while there were obvious differences existing in the porewater of the marshes,especially in spring and autumn.Phosphate characterized with an increasing trend with depthsof soils.Ammonium was the main form of dissolved inorganic nitrogen and ranged from 35-200 μmol/L.The contents of NO 2 —N＋NO 3 —N ranged from 3-10 μmol/L,and NO 3 —N concentration was relatively higher.Compared to native species in Cyperus malaccensis marsh,the invasive species in Spartina alterniflora marsh had higher ammonium content in porewater of and lower N/P value.The invasion of Spartina alterniflora had some influences on porewater nutrient cycles of the native species Cyperus malaccensis marsh in the Min River Estuary.This study showed an important value in assessing the ecological result of Spartina alterniflora invasion and restoring the native communities.
出处
《湿地科学》
CSCD
北大核心
2013年第1期68-74,共7页
Wetland Science
基金
国家自然科学基金项目(41071148
40671174)
福建师范大学旗山学者项目
福建省自然科学基金项目(2012J05073)资助
关键词
间隙水
营养盐
垂直分布
潮汐沼泽
闽江河口
porewater
nutrient salt
tidal marsh
vertical distribution
Min River Estuary
