| 摘要: | Of late years, it has been quite rapidly in the development of Quantitative Geomorphology, which might have been playing an imperative theme in Geographic study. Geomorphometry, that is a process to use measuring means, to handle the character of land surface, and finally to recognize the nature of land surface. Geomorphometry, however, is an important method in the research of Quantitative Geomorphology. Whether the Geomorphometric method is used properly, it always gives a direct influence to the investigative result in Quantitative Geomorphology.
For some of the past years, this research is possible under the expense defrayed by the National Science Council making a great deal of Geomorphometric work and based on the digital data of land character which were acquired, so that one could do further review to Geomorphometric method by means of substantial metric examples of height, slope and relief in order to provide a suitable metric form, and to be a referable basis of Geomorphometric work.
This paper has been divided into two parts. The frist is ”Review of Geomorphometric Method”. After analyzing various metric method, map scales and grid scales, these individual metric results were combined to emphasize the function, of Geomorphometry. According to the result of the research, the following conclusions are obtained:
(1) Central point method, contour density method and relief method are the most proper method for the metry of height, slope and relief.
(2) There is a relationship of direct proportion among the metric results of height and slope to map scales.
(3) The grid scale of using 1 km^2 is seen fit to general purpose for measuring height, slope and relief in Taiwan area.
(4) The relationship among height, slope and relief of land surface in Taiwan area can be expressed by the following:
(i) H=l.96S^2-12.23S + 66.89;
(ii) R=1.91S-50.1;
(iii) H= 0.003R^2+1.24R + 25.63.
(5) After comparison, the metric result of different grid scales could be converted on the basis of experimental formulas as follows:
(a)- Slope: y =0.025 logx + 1.8 (x is the enlarged multiple of grid scale; y is the enlarged multiple of slope degrees).
(b) Relief: RHR=(The Symbol is abbreviated) (Where R and R' are differeng rid scales K is a constant, while a smaller grid was converted into a longer grid, it was 0.8; convesely, it was 1.25.
(6) The relief area could be computed using mean slope degrees (θ), here the experimental formulas is
GR (%) = (Secθ-1)×100 +θ/2R
(G is the increasing rate of area; R is the classified Range of slope degrees.)
The second part is ”The Processing Model of Geomorphometric Method”. Based on the highest point (H) and the lowest point (L) within each metric grid, in addition to computer operating, a HLGP model of Geomorphometry is designed. It has the characteristics of rapidity, few errors and multiplex functions and can replace the traditional metric method, so that one could make much more preparations for establishing a landform data bank of Taiwan area. There were some substantial achievements on drawing three-dimension map and digital map during the computer work. Computer program such as HLP, MPP, PLP, LTP and SFCFS etc. are designed under the existing national conditions. Hereof, this study provides a reference for progress of the automatic operation in the future. |
