CAJ | 학술논문

利用小集水区生态水文学模型-Topog模型对雷州半岛桉树人工林纪家示范小集水区进行了地形分析和静态水文学模拟.地形分析表明,该集水区地表较为平坦,集水区总面积为0.63 km2,夏季、冬季与春(秋)分平均太阳辐射值分别为44 MJ·m-2·d-1、25 MJ·m-2·d-1和34 MJ·m-2·d-1.在考虑太阳辐射影响与不考虑太阳辐影响两种情况下进行了集水区土壤含水量指数(WI)静态模拟.设定不同的静态壤中流参数值,Topog模型模拟结果表明,静态壤中流越大,在集水区内高WI的分布范围越大,也即土壤含水量越高.在考虑太阳辐射影响的条件下,分别设置不同的土壤导水率(T)、地表阴蔽系数(Es)、平均降雨量(R)进行了模拟.模拟结果表明,WI分布依各参数的不同而变化.T越大,在集水区内的WI重新分布越快;T越小,在集水区内WI趋向于平均分布.Es越大,集水区土壤所保持的含水量越高.集水区WI随R增大而有升高趋势.
이용소집수구생태수문학모형-Topog모형대뇌주반도안수인공림기가시범소집수구진행료지형분석화정태수문학모의.지형분석표명,해집수구지표교위평탄,집수구총면적위0.63 km2,하계、동계여춘(추)분평균태양복사치분별위44 MJ·m-2·d-1、25 MJ·m-2·d-1화34 MJ·m-2·d-1.재고필태양복사영향여불고필태양복영향량충정황하진행료집수구토양함수량지수(WI)정태모의.설정불동적정태양중류삼수치,Topog모형모의결과표명,정태양중류월대,재집수구내고WI적분포범위월대,야즉토양함수량월고.재고필태양복사영향적조건하,분별설치불동적토양도수솔(T)、지표음폐계수(Es)、평균강우량(R)진행료모의.모의결과표명,WI분포의각삼수적불동이변화.T월대,재집수구내적WI중신분포월쾌;T월소,재집수구내WI추향우평균분포.Es월대,집수구토양소보지적함수량월고.집수구WI수R증대이유승고추세.
Many hydrological characteristics of a catchment can be inferred from its topography. The eco-hydrological model, Topog, uses a sophisticated analysis of topography to describe the hydrological characteristics of a catchment in detail. This paper describes an integrated terrain analysis and steady state hydrological modelling study of a small forest catchment on Leizhou Peninsula, southern China using Topog. The terrain analysis was based on a DEM (digital elevation model) of the central part of the peninsula including the upper valley of the Nandu River. The basic hydrologic characteristics defining the Jijia catchment were catchment boundary, high points and saddles, calculated ridges and streams, and an element network separating the catchment into a large number of relatively uniform units for modelling. The topographic attributes of each element were calculated automatically, including slope, aspect, upslope contributing area and potential incident solar radiation. The slope of the catchment was relatively low: the difference between slopes of most elements was in the range of 2.8~5.7 degree, or less than 2.8 degree. The general description of the Jijia catchment provided by Topog included total catchment area of 0.63 km2 and average amount of incident radiation of 44, 25, and 34 MJ·m-2·d-1 for summer, winter and equinoxes, respectively. The catchment convergence index and steady-state wetness indices (WI) of the elements of the Jijia experimental catchment with and without solar radiation-weighting were also obtained. From steady-state drainage flux modelling, we obtained a distribution of WI across the catchment. By setting different parameter values of uniform drainage flux, the mapped simulations of WI over the catchment indicated that the bigger the uniform drainage flux was, the higher the WI would be.We modelled a radiation-weighted drainage index at different values of uniform transmissivity (T), different shaded soil fraction (Es), and different uniform rainfall (R). The result illustrated that the mapped distribution of WI varies as a consequence of these different data inputs. The distribution of WI was strongly affected by T values which indicated that soil wetness within some stream zones might extend more widely, given a bigger T value. Conversely, lower values of T resulted in more uniform spatial distribution of WI over the catchment. Modelled results also varied with shaded fraction, which indicated that a small increase in solar radiation would result in spatially different distribution of soil moisture content over the catchment. Finally, we made a comparison between a set of uniform rainfall values and found that Topog predicted the expected trend that soil moisture within the catchment increased with increasing uniform rainfall values.