不同满江红C、N、P生态化学计量学的季节变化

Seasonal Variation on Ecological Stoichiometry of Carbon,Nitrogen and Phosphorus in Azolla Cultivars

为了评价不同满江红的生态化学计量特征的差异,以8种不同满江红为对象,在网室土壤水培养条件下,研究季节变化对满江红产量,碳(C)、氮(N)、磷(P)含量及其化学计量比的影响。结果表明:随温度的增加,满江红的生物量产量呈先升高后降低趋势,在夏季达到最高。四季平均产量最高为闽育1号小叶萍4087,达244.25g·盆-1,第二为回交萍MH3-1,达240.43g·盆-1,第三为卡州萍3001,达232.14g·盆-1。满江红的C含量呈先降低再逐渐升高,C含量在春季达到最高,达44.40%;N、P含量表现为先升高再降低的趋势,在夏季达到最高,分别达4.50%和0.86%,综合C、N、P含量,卡州萍3001、细绿萍1001、墨西哥萍2002的C、N、P含量明显优于其他的满江红。满江红C∶N、C∶P和N∶P随温度变化呈先降低再升高趋势,夏季达最低。不同满江红在不同季节C∶N、C∶P和N∶P变化范围分别为7.93~18.20、41.05~225.18、5.16~23.90。本试验条件下,综合生物量产量、C、N、P含量,卡州萍3001的特性优于其他的满江红。

Ecological stoichiometry of different Azolla cultivars as affected by the seasons was studied.In the lab,8 Azolla cultivars were used to determine the seasonal variations on yield,contents of C,N,P as well as stoichiometry of the plants.The results showed the yield increased initially,reached a peak as the temperature rose in the summer,and followed by a decline.The highest average annual yield of 244.25 g·tray-1 was observed on A.microphylla Minyu No.1(4087),the second highest of 240.43 g/tray on A.microphylla(4018)A.filiculoides(1001)A.microphylla(4018)MH3-1,and the third of 232.14 g·tray-1 on A.caroliniana Willd(3001).The C content in them was low at first but gradually increased later to arrive at the highest at 44.40%in the spring.The contents of N and P increased firstly to their maximum,4.50%and 0.86%,respectively,in the summer,then decreased.The C,N and P contents of A.caroliniana Willd(3001),A.filiculoides lamarck(1001)and A.Mexicana Schlecht et cham(2002)were higher than those of the other cultivars.As the temperature varied,the ratios of C∶N,C∶P and N∶P decreased in the beginning to their lowest values in the summer and followed by an increasing trend.The ratios varied between 7.93-18.20,41.05-225.18 and 5.16-23.90,respectively,in different seasons.Under the experimental conditions,A.caroliniana Willd(3001)was found superior to others on yield and contents of C,N and P.