作　　者： ; ; ; ; ;

机构地区： 华南农业大学资源环境学院

出　　处： 《生态学杂志》 2009年第12期2579-2585,共7页

摘　　要： 按照广东大宝山矿酸性矿山废水对横石水河的酸性污染梯度,从上游到下游在横石水河及其支流设置7个污染样点、3个清洁样点,利用孔径为0.5mm的分解网袋采集了2种树叶(藜蒴,Castanopsis fissa;荷木,Schima superba),研究树叶凋落物在不同污染梯度下的分解状况。结果表明,随着pH值逐渐升高,水体重金属浓度逐渐降低,2种树叶的分解速率逐渐加快,各污染样点的分解速率均显著低于清洁样点的分解速率(P<0.05),其中藜蒴和荷木的树叶凋落物在清洁点I点的分解速率分别比距离污染源头最近、污染最重的样点A快6.5和10.5倍。回归分析表明,2种树叶的分解速率均与河流的pH值呈正相关,与河流的Cu、Cd、Zn、Pb4种重金属浓度呈负相关,即河流pH值越低,重金属含量越高,树叶分解速率越慢。说明树叶凋落物的分解速率对水质变化是比较敏感的,可以作为评价河流生态系统完整性的一个参数。 According to the pollution gradient of Hengshishui River contaminated by the acid mine drainage（AMD）from Dabaoshan Mine of Guangdong,seven contaminated sites and three non-contaminated sites were selected from the upstream to the downstream of Hengshishui River and its branches.The leaf litters of Castanopsis fissa and Schima superba enclosed in 0.5 mm mesh bags were put in these sites to study their decomposition rate along the pollution gradient.With the increase of water pH and the decrease of heavy metals concentration in river water,the decomposition rates of the two species of leaf litters increased gradually,and were significantly lower in contaminated sites than in non-contaminated sites（P0.05）.At the non-contaminated site I,the decomposition rates of C.fissa and S.superba leaf litters were 6.5 and 10.5 times higher than those at the most contaminated site A which was closest to the Mine.The leaf litter decomposition rates were positively correlated with water pH,and negatively correlated with the Cu,Cd,Zn,and Pb concentrations in river water,suggesting that the lower water pH and the higher heavy metals concentration in river water could result in a lower leaf decomposition rate.Our results indicated that leaf litter decomposition rate was sensitive to the changes in water quality,and could be used as an indicator in the evaluation of stream ecosystem integrality.

关 键 词： 树叶凋落物 分解速率 酸性矿山废水 响应

领　　域： [生物学] [生物学] [环境科学与工程]