| 摘要: | The Pu Li Basin Group, a series of intermontane basins, is located in a depressed area among the mountainous region of Central Taiwan with a strike of NNE-SSW which goes with the main structural line ad the island. It includes 16 basins that differ in altitude and size.
Geologically, it was formed chiefly by dowuwarping and faulting in Tertiary. They become lakes afterwards. By now, all but Sun-Moon Lake are dried up by siltation and headward erosion. There are evidences showing that many, of them have been dissected by streams. The Pu-Li Basin, the most dissected one, has a floor which can be divided into two parts, the higher plain and the lower plain. The Town of Pu Li is situated at the center of the lower plain.
Because of its geographical environment, the Basin Group has a transitional climate between the western plains and the Central Mountain Range with mild, dry winter and warm rainy summer. Annual mean temperature is from 19.4℃ at Sun-Moon Lake to 22℃ at Pu-Li. Annual precipitation is ahout 2,000-2,500 mm at an average. During the rainy season from April to September, the amount of rainfall can be increased to 1,800-2,100 mm which makes up 86 of the total. Under the .influence of the basinal type of landform, the average wind velocity is under 1.5 meters per second, considerably weaker than the other parts of Taiwan.
Soil groups are various. They include alluvial soils, red earths, vellowearths, lithosols and gray-brown podzolic soils.
Cultural development is late but rather quick. Native aborigines were dominant before the 19 century. The Basia Group has a population of more than 90,000 with a density of over 300 persons per square kilometer. The use of land is intensive and the pattern is changing rapidly. Various crops can be seen in the cultivated lands. Rice is the leading one. Other important erops include tea, banana, and auger cane. Owing to the excessive use of slopes and the poor methods of cultivation, soil erosion is very serious.
Water power resources are rich. Sun Moon Lake has long been dammed for generating pawer which supports over one-third of the total hydroelectricity of Taiwan. This region is also famous for its scenery and aboriginal remains which have changed Sun-Moon Lake into one of the most attractive centers for foreign tourists. |
