在无锡太湖湖滨带布设3条样带、36个样点进行了调查,分析了表层沉积物(0～15 cm)和芦苇(Phragmites australis (Cav.)Trin.)、茭白(Zizania latifolia (Griseb.)Turcz.)2种挺水植物w(N)、w(P)的变化,揭示了沉积物N、P的空间分布以及与2种挺水植物N、P的关系.结果表明:(1)表层沉积物w(N)自上而下分别为7.89～4.24 mg·g-1(0～5 cm)、7.56～3.81 mg·g-1(0～10 cm)、7.61～3.77 mg·g-1(0～15 cm),w(P)分另为1.293～0.532 mg·g-1(0～5 cm)、1.112～0.497 mg·g-1(0～10 cm)、0.952～0.471 mg·g-1(0～15cm).(2)生态修复区表层沉积物N、P的水平变化规律一致,按陆向辐射区-水位变幅区-水向辐射区依次递减,而从垂直变化来看,w(N)、w(P)均以表层最高,并依次向下层递减；硬质护坡区P的变化与之一致,但N的水平分布却按陆向辐射区-水位变幅区-水向辐射区依次递增,垂直分布呈现表层最低,并依次向下层递增变化.(3)2种挺水植物w(N)、w(P)不同,芦苇对N、P的吸收明显高于茭白(芦苇地上部分w(N) 31.75～42.61 mg·g-1,地下部分w(N) 13.57～18.21 mg·g-1;茭白地上w(N)14.78～23.57 mg·g-1,地下部分w(N) 13.57～18.21 mg·g-1,而芦苇地上部分w(P) 3.62～5.08 mg·g-1,茭白地上部分w(P) 1.42～1.93mg·g-1,地下部分w(P) 0.35～0.57 mg·g-1).2种挺水植物地上部分N、P吸收量远远大于地下部分吸收量.(4)相关分析表明,2种植物地下部分w(TP)与沉积物w(TP)呈正相关,而芦苇地下部分w(TP)与沉积物w(TP)相关性显著(P＜0.05),说明芦苇根系对沉积物中的P具有强烈吸附作用.(5)2种植物对太湖中沉积物N、P分配有显著影响,生态恢复区沉积物中w(N)显著高于硬质护坡,而w(P)较硬质护坡显著降低,适度恢复水生植被可有效缓解湖泊水体的富营养化.%Three sample lines and 36 surface sediments(0~15 cm) were surveyed and sampled from various sections in riparian zone of Tai Lake Wu Xi, N and P mass fraction in sediments and two emerged plants(Phragmites australis and Zizania latifolidyttere analyzed, relationship between them were discussed too. The results showed that: (1)N contents in surface sediments were from top to bottom 7.89-4.24 mg·g-1(0-5 cm), 7.56-3.81 mg·g-1(0-10 cm), 7.61-3.77 mg·g-1(0-15 cm); P were 1.293-0.532 mg·g-1(0-5cm), 1.112-0.497 mg·g-1(0-40 cm), 0.952-0.471 mg·g-1(0-15 cm). (2)Horizontal change pattern of N and P of sediments in ecological restoration area( I and II) were consistent, that was declined according to the order ,the terrestrial area, the transition area of water and terrene , the water area, while that of N and P in vertical direction was that the N and P contents was the most in surface sur-face(0-5cm),and it declined to the low. The change of P in cement slope area(III)were so,but that of N reversed. (3) N and P contents of two emerged plants were different, absorption of N and P of P. Australis was higher than Z latifolia. According to the analyzed results, N contents of P. Australis was 31.75-42.61 mg·g-1 in overground part(OP), 13.57-18.21 mg·g-1 in underground parts(UP); that of Z. Latifolia was 14.78-23.57 mg·g-1(OP) and 13.57-18.21 mg·g-1(UP). P absorption of P. Australis was 3.62-5.08 mg·g-1(OP), and that of Z latifolia was 1.42-1.93 mg·g-1(OP), 0.35-0.57 mg·g-1(OP). Their absorption of both N and P in OP was bigger than tha in UP. (4)The correlation analyze showed TP in UP of two emerged plants and TP in sediments has a positive correlation, and the correlation of P. Australis was obvious(p < 0.05), so sorption of P. Australis roots to P in sediments was very strong. (5)Two emerged plants has important effects on the distribution of N and P in sediments, N contents in ecological restoration area was higher than that in cement slope area, but P contents chang reversed, so the reasonable restoration emerged plants in lakeside wetland was one of the effective measures to relieve the eutrophication.
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