我国の都市における水空間とその変遷

抄録

The area and length of waterspace (river, watercourse, canal and pond) are measured and compared, late in the Yedo period (about 1850) and today, in the same urbanized area of 20 cities based on castle towns in japan.
We propose 2 indexes (Rw, Dw) to judge the quantity of waterspace.
Rw=Aw/Au×100 (%)-the ratio of waterspace to urbanized area
Dw=Au/Lw×0.5 (m)-the arriving distance at waterspace
Aw: Fhe area of waterspace urbanized area in the city.
Lw: The length of waterspace urbanized area in the city.
Au: The area of urbanized area in the city.
The followings are some result,
1. Lw in 19 cities and Aw in all 20 cities have decreased.
2. The average Rw was 10.7% and is 7.6% today. It decreased by about 30%.
3. The average Dw was 199m and is 306m today. It increased by about 50%.