地理科学进展
地理科學進展
지이과학진전
PROGRESS IN GEOGRAPHY
2010年
3期
287-291
,共5页
湿周法%最小生态需水量%斜率为1法%曲率最大法%滦河
濕週法%最小生態需水量%斜率為1法%麯率最大法%灤河
습주법%최소생태수수량%사솔위1법%곡솔최대법%란하
the wetted perimeter method%the minimum instream flow%slope equaling 1 method%maximal curvature method%Luanhe
湿周法是以湿周作为衡量栖息地质量的指标来估算河道内流量的最小值.通过建立河道断面湿周与流量的关系曲线,依据该曲线确定变化点的位置,估算最小需水量的推荐值.根据国外对湿周法的研究应用,分别采用对数函数和幂函数关系对湿周一流量关系进行拟合.从理论上分析了湿周法采用斜率为1法和曲率最大法确定变化点的不同,得到不论采用对数函数还是幂函数关系拟合流量一湿周关系,斜率为1法的估算结果都要大于曲率最大法的估算结果.把湿周法应用到滦河流域两个水文站,以曲率最大法确定变化点,估箅了两个站点的最小生态需水量.结果表明:①对数函数拟合流量-湿周关系得到的最小生态需水量都要大于幂函数拟合流量-湿周关系的结果;②湿周法估算的生态需水量都能满足河道内最小生态需水的要求,且较小河流对生态需水量的要求相对较大河流更高.
濕週法是以濕週作為衡量棲息地質量的指標來估算河道內流量的最小值.通過建立河道斷麵濕週與流量的關繫麯線,依據該麯線確定變化點的位置,估算最小需水量的推薦值.根據國外對濕週法的研究應用,分彆採用對數函數和冪函數關繫對濕週一流量關繫進行擬閤.從理論上分析瞭濕週法採用斜率為1法和麯率最大法確定變化點的不同,得到不論採用對數函數還是冪函數關繫擬閤流量一濕週關繫,斜率為1法的估算結果都要大于麯率最大法的估算結果.把濕週法應用到灤河流域兩箇水文站,以麯率最大法確定變化點,估箄瞭兩箇站點的最小生態需水量.結果錶明:①對數函數擬閤流量-濕週關繫得到的最小生態需水量都要大于冪函數擬閤流量-濕週關繫的結果;②濕週法估算的生態需水量都能滿足河道內最小生態需水的要求,且較小河流對生態需水量的要求相對較大河流更高.
습주법시이습주작위형량서식지질량적지표래고산하도내류량적최소치.통과건립하도단면습주여류량적관계곡선,의거해곡선학정변화점적위치,고산최소수수량적추천치.근거국외대습주법적연구응용,분별채용대수함수화멱함수관계대습주일류량관계진행의합.종이론상분석료습주법채용사솔위1법화곡솔최대법학정변화점적불동,득도불론채용대수함수환시멱함수관계의합류량일습주관계,사솔위1법적고산결과도요대우곡솔최대법적고산결과.파습주법응용도란하류역량개수문참,이곡솔최대법학정변화점,고폐료량개참점적최소생태수수량.결과표명:①대수함수의합류량-습주관계득도적최소생태수수량도요대우멱함수의합류량-습주관계적결과;②습주법고산적생태수수량도능만족하도내최소생태수수적요구,차교소하류대생태수수량적요구상대교대하류경고.
Wetted perimeter approach estimates instream flow using wetted perimeter as an index to scale the habitat quality. It estimates minimum environmental flows via determining break point on curve of the relation-ship between wetted perimeter and discharge. This paper adopted logarithmic and power function methods re-spectively to simulate the relationship between wetted perimeter and discharge based on the foreign experience of research and application. The difference of determining breakpoint using slope equaling 1 method and using maximal curvature method was analysed in theory when the wetted perimeter method was used. The results showed that all calculating results from slope equaling 1 method were higher than those from maximal curvature method. The wetted perimeter method was used at two hydrological stations of the Luanhe drainage basin. The results were: (1) The minimum instream flow results were all higher when discharge and wetted perimeter rela-tion fitted by the logarithmic function than that when discharge and wetted perimeter relation fitted by the power function; (2) The minimum instream flow calculated by the wetted perimeter method could satisfy the minimum instream flow requirement, and the minimum instream flow requirement for small rivers is correspondingly higher than that for big rivers.