台灣各縣市十四年來之稻米單位面積產量及秈梗稻一二期作產量比

Abstract

1.根據台灣省糧食局過去十四年來的糧食統計要覽資料，以縣市為單位計算和圖示秈稉稻一、二期作的單位面積糙米產量及秈/稉，II/I期作產量比。 2.據資料顯示，本省稻作區域可劃分為四區： (1)低產地區包括台北、桃園、新竹及苗栗縣 (2)中等低產地區包括宜蘭、花蓮及台東縣 (3)一期作顯著高產但二期作低產地區，包括高雄及屏東縣 3.秈稻單位面積產量比稉稻高者，第一期作僅有南投縣，第二期作雲林縣偶而亦有此現象。台中縣一二期作秈稉稻產量之差幅十分小。其他縣市的秈稻均比稉稻低產，幅度約為5%至30%不等。一般而言，秈稻比稉稻低產之問題在第二期作比較來得嚴重。 1. Using the data released by the Taiwan Provincial Food Bureau, average yields of brown rice per hectare and yield ratios of II/ I crops and Sen/keng (or indica/japonica) rices were calculated and illustrated on the hsien (county) basis for the past 14 years. 2. According to the statistics, the rice areas of the province could be divided into 4 areas: (1) low yielding area including Taipei, Taoyuan, Hsinchu, and Miaoli hsien. (2) intermediately low yielding area including Ilan, Hwalien and Taitung hsien. (3) the area significantly high yielding in the first crop but low yielding in the 2nd crop including Kaohsiung and Pingtung hsien. (4) intermediately high yielding area including 7 hsien and city in Taichung and Tainan districts. 3. The yield per unit area of Sen rice consistently surpasses that of Keng rice only in Nantou hsien in the first crop and frequently in Yunlin hsien in the second crop. In Taichung hsien, the yield difference between the two rices is very small in both crops. In other hsien and cities, Sen rice yields lower than Keng rice 5%-30%. Generally, lower yield of Sen rice than Keng rice is more striking in the second crop. 4. Taichung city, with about 9,700 has of rice area, is the only place on the island where the second crop of the two rices outyields or yields the same with the first crop, except in the year of typhoon and dry monsoon damages. The yield decrease of the second crop rice is most distinct in Taipei, Ilan, Kaohsiung, Pingtung hsien (about 30%-60%) and in other hsien (10%-30%). Generally, lower yield of the second crop compared with the first crop is more obvious in Sen rice. 5. Climatic conditions that caused damage to the first crop rice were prolonged rain in the central and southern districts, hot south-west air current in the entire province and low temperatures in Kaohsiung district. The prolonged rain generally occurs in May and June every year but causes damage to the rice plant once about every 10 years by inducing various degrees of diseases and insects, seed germination on the paincle and lodging of the plant. Typhoon, dry monsoon and prolonged rain are the major climatic menaces to the second crop rice. Typhoon affects the entire province, and dry monsoon attacks the coastal areas in the north of Changhwa and Hwalien hsien. Prolonged rain accompanied by low temperatures and weak solar radiations causes yield reduction of the second crop rice in Taipei, Hsinchu districts and Hwalien hsien.