Page 26 - 2024年第55卷第12期
P. 26

[31] 冯顺新,廖文根,王俊娜,等.水文过程与近岸带变化关系及其河流景观内涵[J].中国水利水电科学研
                       究院学报(中英文),2022,20(3):181 - 192.
                [32] 谢鉴衡.河床演变及整治[M].北京:水利水电出版社,1997.
                [33] 王华琳,郑珊,谈广鸣,等.三峡水库运行后宜昌- 城陵矶河段冲刷重心下移与时空演变[J].水利学报,
                      2021,52(12):1470 - 1481.



                           Evaluationandcausesanalysisofchangesinmorphologicaldiversityin
                             Yichang - Chenglingjireachdownstream oftheThreeGorgesDam

                                           1
                                                                         2
                                                       1
                                                                                     2
                                   CHENLi,YUBowen,YANGChenggang,YUANJing
                      (1.StateKeyLaboratoryofWaterResourcesEngineeringandManagement,WuhanUniversity,Wuhan 430072,China;
                              2.BureauofHydrology,ChangjiangWaterResourcesCommission,Wuhan 430010,China)
                  Abstract:Thediversityofriverchannelmorphologylargelydeterminesthediversityofphysicalhabitatsforriverine
                  organisms,playinganimportantroleinshapingtheabundanceanddiversityofaquaticbiologicalspecies.Afterthe
                  impoundmentoftheThreeGorgesDam ,downstreamriverbedunderwentsevereerosionanddepositionadjustments,
                  leadingtochangesinriverchanneldiversity.Usingfield - measuredfixedcrosssectionmorphologydatafrom
                  YichangtoChenglingjiinthedownstream reachoftheThreeGorgesDam duringtheyears2003and2018 ,the
                  compositediversityindexoftheriverchannelwasconstructedbasedonindexesoflongitudinaldiversity ,lateraldi
                  versityandbathymetrichabitatintegrity.Theseindexeswereemployedtoanalyzethedifferencesindiversitybe
                  tweendifferentriverpatternsandreachesaftertheimpoundmentoftheThreeGorgesDam ,andthecausesofthe
                  changes.Theresultsrevealedthat,morphologicaldiversityvariedacrossdifferentriverpatterns,withcorrespond
                  ingdifferencesinmorphologicaldiversityamongdifferentreaches.Meanderingriverpatternsexhibitedalowerkur
                  tosiscoefficientandahigherproportionoflowbars ,resultinginhigherdiversitycomparedtootherriverpatterns.
                  Consequently ,theLowerJingjiangRiver,primarilycharacterizedbymeanderingriverpattern,exhibitedgreater
                  diversitythanotherreaches.Followingreservoirimpoundment ,overallmorphologicaldiversityinthedownstream
                  reachesgenerallydecreased.However ,changesinmorphologicaldiversityvariedamongdifferentriverpatternsand
                  reaches.Kurtosiscoefficientsincreasedsignificantlyinstraightriverpatternsunderbothlowandbankfulwaterlev
                  els ,andwasincreasinginbifurcatedriverpatternsunderlowwaterlevel,butdecreasedformeanderingpatterns
                  underbankfulwaterlevel.Accordingly,thekurtosiscoefficientoftheLowerJingjiangReach,dominatedbymean
                  deringpatterns ,decreased.Thedifferenceinpost - damerosionanddepositionadjustmentpatternsbetweendifferent
                  riverpatternswastheintrinsicmechanismthatledtodifferenttrendsindiversitychange.Theresearchfindingscan
                  supporttounderstandthechangesinriverinehabitatsundertheinfluenceofhumanactivities.
                  Keywords:riverhabitat;diversity;ThreeGorgesDam;riverchannelerosion

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