长江中游洲滩植被生长动态及其对水流阻力的影响  

Growth dynamics of vegetation on floodplains in middle reaches of the Yangze River and its impact on flow resistance

作　　者：刘胜琪 夏军强[1] 石希 周美蓉[1] 辛沛[2] LIU Shengqi;XIA Junqiang;SHI Xi;ZHOU Meirong;XIN Pei(State Key Laboratory of Water Resources Engineering and Management,Wuhan University,Wuhan 430072,China;The National Key Laboratory of Water Disaster Prevention,Hohai University,Nanjing 210098,China)

机构地区：[1]武汉大学水资源工程与调度全国重点实验室,湖北武汉430072 [2]河海大学水灾害防御全国重点实验室,江苏南京210098

出　　处：《水资源保护》2025年第2期233-241,共9页Water Resources Protection

基　　金：国家自然科学基金项目(U2040215,52109098)。

摘　　要：以长江中游洲滩典型水生植物芦苇为研究对象,构建了考虑淹水胁迫影响的芦苇生长模型及其生物量分层模型,提出了一种考虑芦苇生长动态的等效曼宁糙率计算方法,分析了不同洪水淹没条件和不同芦苇生长过程对等效曼宁糙率的影响,并建立了非淹没状态下等效曼宁糙率与芦苇地上生物量、相对淹没度的经验计算公式。结果表明:考虑淹水胁迫影响的芦苇生长模型可以较好地模拟芦苇地上生物量和形态参数的变化过程,模拟结果纳什效率系数为0.85~0.94;芦苇生物量和阻水面积有相似的垂向分布规律,以相对高度0.3为界限,芦苇茎阻水面积上小下大,叶阻水面积下小上大,在相对高度0.7以下芦苇总阻水面积和地上生物量近似呈均匀分布;最大等效曼宁糙率计算值约为0.300,淹水胁迫影响下芦苇地上生物量减少,导致同水深条件下等效曼宁糙率值减小10.0%~29.1%。Taking the typical beach equatic plant,phragmites australis,as the study object,a growth dynamic model of Phragmites australis considering flooding stress and a hierarchical model of biomass were established in this study.A calculation method was then proposed of equivalent Manning roughness which considered the growth dynamic of Phragmites australis.Based on this method,the differences in equivalent Manning roughness under different Phragmites australis growth processes and flooding conditions were analyzed.An empirical formula was established between the equivalent Manning roughness,aboveground biomass of Phragmites australis,relative submergence degree under the non-submerged condition.The results show that the growth dynamic model could effectively simulate the change processes of aboveground biomass and morphology parameters of Phragmites australis,with the Nash efficiency coefficient ranging between 0.85 and 0.94.Similar vertical distribution patterns existed in biomass and flow blocking area of Phragmites australis.With a critical relative height of 0.3,the flow blocking area of stems was characterized by more below and less above,and the flow blocking area of leaves was characterized by less below and more above.The total flow blocking area and aboveground biomass of Phragmites australis were approximately uniformly distributed below a relative height of 0.7.The calculated maximum equivalent Manning roughness was approximately 0.300.Under the effect of flooding stress,the aboveground biomass of Phragmites australis decreased,resulting in a 10.0%~29.1% reduction in equivalent Manning roughness under the same water depth.

关 键 词：芦苇生长 等效曼宁糙率 生物量 阻水面积 相对淹没度 长江中游 

分 类 号：TV131[水利工程—水力学及河流动力学] Q948[生物学—植物学]