Du Jingna, Yu Junyi
a School of Life Science , Guizhou Normal University , Guiyang , China.
b Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems , Xiamen University , Xiamen , China.
Int J Phytoremediation. 2017 Jul 3;19(7):658-661. doi: 10.1080/15226514.2016.1278425.
Mangrove [Kandelia obovata (S. L.)] seedlings were cultivated in rhizoboxes under different rates of phosphorus (P) and cadmium (Cd) level. The speciation distributions of P both in the rhizosphere and non-rhizosphere sediments were examined using sequential extraction procedures. P contents in different K. obovata (S.L.) tissues were also determined. Results showed that considerable differences existed in P speciation distribution between rhizosphere and bulk sediments. A higher proportion of iron-bound phosphate (Fe-P) was found in the rhizosphere sediments, while a relatively higher concentration of exchangeable phosphate (Ex-P) and Aluminum-bound phosphate was found in the bulk sediments. P accumulation in plant tissues was significantly positively correlated to Ex-P and Fe-P. Results indicated that root activities play an important role in the P cycling. And the coexistence of P and Cd induced higher P accumulation in mangrove plants. It is suggested that the root-induced chemical and biological changes in the rhizosphere environment play an important role in enhancing the bioavailability of soil P.
在不同磷（P）和镉（Cd）水平下，将秋茄[Kandelia obovata (S. L.)]幼苗种植在根际箱中。采用连续提取法研究了根际和非根际沉积物中磷的形态分布。还测定了不同秋茄（S.L.）组织中的磷含量。结果表明，根际沉积物和大块沉积物之间的磷形态分布存在显著差异。在根际沉积物中发现较高比例的铁结合态磷（Fe-P），而在大块沉积物中发现相对较高浓度的可交换态磷（Ex-P）和铝结合态磷。植物组织中的磷积累与Ex-P和Fe-P显著正相关。结果表明，根系活动在磷循环中起重要作用。磷和镉的共存导致红树林植物中磷的积累增加。研究表明，根系诱导的根际环境化学和生物学变化在提高土壤磷的生物有效性方面起重要作用。
