滩地芦苇和杨树群落对汛期水流及泥沙沉积的影响  

Effect of reed and poplar plantation on the flow rate and sedimentation thickness in the flood period on the beach

作　　者：吴敏[1] 吴立勋[1] 汤玉喜[1] 徐世凤[1] 林建新 

机构地区：[1]湖南省林业科学院,湖南长沙410004 [2]沅江市林业局,湖南沅江413100

出　　处：《湖南林业科技》2014年第4期13-17,共5页Hunan Forestry Science & Technology

基　　金："十二五"农村领域国家科技计划课题"林业血防生态安全体系构建技术研究与示范"(2011BAD38B07)

摘　　要：为了解湖区滩地不同植被类型、环境因子对汛期水流速度和泥沙沉积的影响,在汛期对洞庭湖洲滩外的河道及杨树林、芦苇地用流速测算仪定点测量水流速度,用水准仪测量滩地海拔5年间的高程变化,冬（春）天直接测量当年泥沙沉积泥块厚度.结果表明：林外河道中部的水流速度显著高于岸边;河道水流速度受滩地植被类型的影响不明显.芦苇地、杨树林内的水流速度显著低于林外,尤以芦苇地为甚.不同植被类型滩地上的泥沙沉积,以湖岸0～ 30 m地段为最厚,芦苇地的平均厚度是杨树林的1.25倍.7～11年生滩地杨树林,因泥沙沉积5年海拔平均增高14.65 cm,年均厚度2.93 cm.滩地上的水流所受阻力,芦苇地大于杨树林,流速显著降低;泥沙沉积量芦苇地显著高于杨树林.杨树林内对泥沙沉积厚度影响最大的因子是湖岸距离,淹水时间居第二位,流速影响最小.In order to find the effects on flood flow velocity and sedimentation by different vegetation types in lake bea- ches and environmental factors, the effect of reed and poplar plantation on the flow rate and sedimentation thickness in the flood period in Dongting Lake area was studied. The flow rate of water stream, poplar plantation and reed beach was investigated by the fluid velocity in the flood period at fixed point, the altitude changes were also conducted by the digital levels, and the sedimentation was measured directly in winter or spring. The results showed that, the flow rate in the middle of water stream was higher significantly than that in the bank, and the flow rate was slightly affected by the type of beach vegetation. The flow rate in the reed and poplar plantation was lower obviously than that of the plantation outside, especially in the reed beach. The sedimentation of different vegetation types was the maximum thickness at the 0 ～ 30 m in the bank, and the thickness of reed beach was 1.25 times of that of the poplar plantation. The altitude increased 14. 65 cm in 5 years in the 7 ～ 11 years old poplar plantation in the beach, and the average annual thickness was 2. 93 cm. The resistance of flow rate in reed beach was higher than that in poplar plantation, and the sedimentation in reed beach was also higher than that in poplar plantation. The affecting factor of sedimentation thickness of poplar plantation was the dis- tance to the lake bank, flooding time and flow rate in order.

关 键 词：滩地 杨树 芦苇 水流速度 泥沙沉积厚度 

分 类 号：S792.119[农业科学—林木遗传育种]