给地面点上降雨产生迳流的过程

半世紀來,水文学在發展的过程中已進入了定量分析的途徑;工程師們曾用各种經驗性的方法依據降水的资料推演河槽裹水流的現象,以应各种工程建設对於水文分析的要求。但是对於降水集流的过程始終祇有一些零星、片面的数值分析,没有一套完整的理論系統,因此阻碍着水文学在理論与应用方面的發展。作者曾用流体力学的分析法初步建立了降水集流的理論系統,把降水集流的过程分為三個階段:雨降地面逕流的產生、地面流、槽流之滙集,分别予以分析。本文便是其中第一階段,亦即最基本水文現象的分析。这些建立了的理論可以用為指導各种水文分析的南針,用為評論各种水文計算法的依據,並可用以創造一种近似而合理的方法,从降水資料推算逕流資料。本文中作者貢献一套理論,以分析地面點上降雨產生逕流的过程,揭發了基本水文現象的本質,最後並列舉实例的計算。早年郝登（R.E.Horton）曾依據郝納（W.W.Homer）的地面流实驗資料建立了一套在小地域內降水和逕流關係之理論,其後学者們根據他的理論和方法,用人工降雨法或流域資料实測法來確定降水和逕流間的關係。郝登的分析並没有从準確的動力学观點出發。在实際分析中發生了欠缺理論基礎的根本問題。这方面作者持着不同的意見。本文中根據作者的理論指出了郝登分析法的癥結所在,並估計了人工降雨实驗法的实用價值之限度。波達闊夫曾建議暴雨逕流之一种計算法,引起了苏联学者的廣泛討論,很多人持有不同的意見。作者於文中指出了波氏等方法發生問題的症結所在;並用实例計算和作者的方法比較,說明了波氏法在实用中的準確限度。

AN ANALYSIS OF HYDROGRAPH OF SURFACE FLOW DUE TO RAINFALL AT A POINT

Since the beginning of the last half century, the science of hydrology through successive steps of development has advanced to the realm of quantitative analysis. Engineers employed empirical methods to compute river discharges from precipitation data in answer to the ever-increasing demands made upon hydrologic analyses for engineering works. Yet for the phenomena of conflux of flows from precipitations, there exist only meager and fragmental quantitative analyses, without, so far, a systematic study of their underlying theories recorded in literature. On account of this, the progress of hydrology in respect to theory as well as to prac- tice has been retarded. By means of hydrodynamic analysis, the author has tentatively made an approach to the establishment of such a scheme of theories, in which he divided the rainfall-runoff phenomena into three parts for separate analyses, i. e., the occurrence of runoff due to rainfall at a surface point, the surface flow, and. the conflux of channel flows. This paper is devoted to the first part, which is, in essence, an analysis of the basic hydrologic phenomena. The theories thus established may be used as a guide for various hydrologic analyses in practice, may be based upon to examine the validity of various methods of hydrologic calculations, and may be further used to develop an approximate yet rational method for computing discharges from precipitation data. In this paper, the author proposes a scheme of underlying theories for analyzing the hydrograph of surface flow due to rainfall at a point, in which the essence of basic hydrologic phenomena is revealed, and this is accompanied with calculations of an example. In the earlier years, R. E. Horton established a theory of correlations of rainfall and runoff from small drainage basins by analyzing the data of Homer's sprinkler experiments. Thereafter, researchers basing upon his theories and methods analyzed the relations between rainfall and runoff by sprinkler experiments or data from natural areas. On account of the fact that Horton's analysis does not begin with an accurate hydrodynamical viewpoint, problems are bound to arise in practice due to defects in the underlying theories. Shortcomings of Homer's analysis on the basis of the author's theories are pointed out and the practical value of sprinkler experiments estimated. A method proposed by E. V. Bodakoff for computing discharges due to storms on small basins has raised wide discussions among the Soviet scholars, many of whom hold different views. The author hereby points out the main shortcomings of Bodakoff's method, and gives a numerical example with results compared with those computed by the author's method, thus showing the limitations of Bodakoff's method in practical applications.