广州南沙湿地大型底栖动物次级生产力时空特征

Spatiotemporal Characteristics of Secondary Production of Macrobenthos in the Nansha Wetland,Guangzhou

2019年12月至2020年10月,在广州南沙湿地的芦苇(Phragmites communis)湿地、无瓣海桑(Sonneratia apetala)湿地和光滩,采集大型底栖动物样品,对其次级生产力、P/B值(次级生产力与生物量的比值)进行计算与分析,探究大型底栖动物次级生产力的时空变化。结果表明,不同湿地大型底栖动物群落次级生产力和P/B值差异明显,芦苇湿地、无瓣海桑湿地和光滩大型底栖动物年均次级生产力(去灰分干质量,AFDW)分别为36.59 g/(m^(2)·a)、13.31 g/(m^(2)·a)和4.56 g/(m^(2)·a),P/B值分别为1.24、1.20和0.84。芦苇湿地大型底栖动物次级生产力最高,其次是无瓣海桑湿地,光滩最低。双因素方差分析表明,大型底栖动物次级生产力和P/B值在不同生境之间差异显著(F=6.50,p<0.01),但在不同季节之间差异不显著(p>0.05)。相关分析表明,大型底栖动物次级生产力与土壤pH显著负相关(p<0.05),P/B值与土壤盐度和电导率均显著负相关(p<0.05)。

From December 2019 to October 2020,macrobenthos samples in three habitats of Phragmites com-munis,Sonneratia apetala and bare flat in the Nansha Wetland of Guangzhou were collected,and the second-ary productivity and P/B value(the ratio of secondary production to biomass)were calculated and analyzed to reveal the spatiotemporal characteristics of macrobenthos.The results indicated significant differences in the secondary productivity and the P/B ratio among the macrobenthic communities across different habitats.The average annual secondary production of macrobenthos in the P.communis weland,the S.apetala wetland and the bare flat were 36.59 g/(m^(2)·a),13.31 g/(m^(2)·a)and 4.56 g/(m^(2)·a),respectively,and the P/B values were 1.24,1.20 and 0.84,respectively.The secondary production of macrobenthos in the P.communis wetland was the highest,followed by that in the S.apetala wetland,and the lowest in the bare flat.A two-way analysis of variance indicated that the secondary production and P/B ratios of macrobenthos differed significantly among the three habitats(F=6.50,p<0.01),but no significant differences were observed among different seasons(p>0.05).Correlation analysis indicated that the secondary production of macrobenthos was significantly nega-tively correlated with soil pH(p<0.05),and the P/B ratio was significantly negatively correlated with soil sa-linity and electrical conductivity(p<0.05).