INTERNATIONAL SYMPOSIUM: BUILDING WITHIN PLANETARY BOUNDARIES https://theorie.arch.rwth-aachen.de/international-symposium-building-within-planetary-boundaries/

1. Beyond fake greening and potential vegetation: parcel nested dynamics of urban ecology
2025/4/26 – Yuji HARA at Wakayama University / hara@wakayama-u.ac.jp / future-landscape.com

2. Osaka plain landform and land use in 2008
(Hara et al. 2014)

3. Wetlands were situated along the main
river course in the center of the plain
Wet rice cultivation was practiced in the
rim of the plain (dry lands in 1880s)
Past and present agricultural lands/green spaces
1880s 2008

4. Johannis De Rijke’s river course work in 1870s

5. 1880s: still wetlands

6. Present: fully urbanized

7. Legacy wetlands only inside river course

11. Excavated soil flows in Osaka (2014-2021)
(Hara et al. 2022)
Seacoast landfills mitigate
inland Satoyama landscape
deteriorations?

15. Osaka Nankou Bird Sanctuary
1979 2007
Built in unused reclaimed land in 1983

17. Facing EXPO 2025 site

18. With a lot of trees behind

19. (Yamagami and Hara 2013)

20. Drastic increase of tree biomass in 30 years
施⼯時と現在の⾼さの⽐較
施⼯時と現在の幹周りの⽐較
0
2
4
6
8
10
12
14
ウバメガシ クヌギ クロマツ アラカシ
ｍ
現在の平均
施工時苗木
施工時立木
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
クヌギ クロマツ アラカシ
ｍ
現在の平均
施工時苗木
施工時立木
Ｇ地区⼭側の種類別本数
Ｇ地区⼲潟近の種類別本数
0
5
10
15
20
25
30
A B C D E F
本
A：アラカシ
B：オオシマザクラ
C：クヌギ
D：トベラ
E：アキニレ
F:ウバメガシ
0
2
4
6
8
10
12
A F Ｇ Ｄ Ｈ I
本
A:アラカシ
F：ウバメガシ
G：クロマツ
D：トベラ
H：シャリンバイ
I：ヒメユズリハ
Not consistent to initially planted species

21. Prof. Miyawaki loved and promoted evergreen forests TOO MUCH

24. (Not wetland restoration but) Tree planting in seacoast fill site
Better for so-called participatory planning

26. BUT in the past natural disturbance must be more frequent

28. (Hara et al. 2018)
Alternative historically important private wetlands under threat
(urbanization/abandoned and toward forest soon)

31. Winter pooling
(photo provided by Dr. Mayura Takada)

34. architect Tadao ANDO’s green wall

41. 0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
20.0
kg/㎡
(Yamaji et al. 2014)

42. 0
2
4
6
8
10
12
14
来園回数
年月
平均値
最大値
最小値

44. (Sampei et al. 2014)
Land parcel based
dynamics of urban
ecology

45. Thank you for your attention!