【摘要】 选取闽江河口潮滩湿地作为研究区,于2013年5、8和11月沿水文梯度采集不同深度土壤,测定其速效磷含量,研究闽江河口潮滩湿地土壤速效磷沿水文梯度的时空分布特征;并进一步测定土壤全磷(TP)、有机磷(Org-P)和无机磷(IP)分级,利用通径分析揭示土壤速效磷来源。结果表明:5月和8月土壤平均速效磷含量分别为3.53±1.15和3.23±1.15 mg·kg-1,显著高于11月(1.96±1.07 mg·kg-1)(P<0.05);5、8和11月土壤速效磷空间分布格局相似,从高潮滩到中潮滩,其含量呈波动降低,并且表现为芦苇群落土壤速效磷含量显著高于短叶茳芏群落(P<0.05);在垂直方向上,高潮滩土壤速效磷含量大都随深度增加而降低,中潮滩其垂直变化不显著;在植物生长初期(5月),土壤Org-P和闭蓄态磷(O-P)是速效磷的主要来源;在植物生长旺盛期(8月)和生长末期(11月),土壤Org-P和铁磷(Fe-P)是速效磷的主要来源。更多还原

【Abstract】 To reveal the spatial-temporal pattern and source of soil available phosphorus( AP)across a subtropical tidal marsh,soil AP,total phosphorus( TP),organic phosphorus( Org-P)and inorganic phosphorus( IP) speciation along a hydrological gradient were examined in Minjiang River estuary of eastern China in May,August and November,2013. The mean concentrations of soil AP in May( 3. 53 ± 1. 15 mg·kg- 1) and August( 3. 23 ± 1. 15 mg·kg- 1) were significantly higher than that in November( 1. 96 ± 1. 07 mg·kg- 1)( P < 0. 05). The distribution patterns of soil AP in the three periods were similar,which showed a fluctuant decrease from high tidal marsh to middle tidal marsh and the higher value was observed in Phragmites australis soil compared with that in Cyperus malaccensis soil( P < 0. 05). Additionally,we observed that soil AP decreased with soil depth in high tidal marsh,while it slightly changed with soil depth in middle tidal marsh. Org-P,iron bound phosphorus( Fe-P) and occluded phosphorus( O-P)were considered as main sources of soil AP in the different vegetation growth periods.更多还原