Role of the EXPO ’70 forest project in forest restoration in urban areas

Abstract

The forest-restoration project of EXPO '70 Commemorative Park, Japan, is an epoch-making attempt to restore a nature-oriented forest park in an urban area in which large-scale land reclamation had occurred. The objective of this paper is to review the concept, planning, and design, and the outcome so far, and discuss current aspects of creating a core natural habitat in the city of Osaka. Innovative planning policy and design methods have been used for construction of the forest-restoration project of EXPO Park.

Estimating stand volume in broad-leaved forest using discrete-return LiDAR: plot-based approach

“…In 1970, the area was used as the site for the world exposition, Expo'70. After the large-scale reclamation, the site was afforested by the forest restoration project from 1972 to 1976 (Morimoto et al 2006). Thirty years has passed since the reclamation, and most of the forest stands have canopies of more than 10 m in height.…”

Evaluating restoration success of a 40-year-old urban forest in reference to mature natural forest

“…However, it is difficult to sustain forest ecosystem functions in harsh urban environments and this has led to degradation of urban forest quality in many cities (Yang et al, 2005;Ishii et al, 2010;La Paixa and Freedman, 2010;Jim, 2013;Ballantyne et al, 2014). Thus forest restoration projects have been conducted in urban areas around the world in an effort to sustain healthy urban forests (Morimoto et al, 2006;Ruiz-Jaén and Aide, 2006;Oldfield et al, 2013;Climate Summit, 2014).…”

“…As goals of the forest restoration, many projects pursue forests comprising native tree species indigenous to the region (Ruiz-Jaén and Aide, 2005b;Hotta et al, 2015;Almas and Conway, 2016;Gatica-Saavedra et al, 2017). These forests are expected to be self-sustaining and resilient to perturbation (Ruiz-Jaén and Aide, 2005a;Morimoto et al, 2006). However, it remains largely unknown whether such restorations will actually produce mature native forest (Oldfield et al, 2013).…”

“…In such forests, tree saplings, mainly composed of native late-successional tree species, are planted at high densities (20,000-120,000 trees/ha 2 ) on improved soil in order to achieve canopy closure within a short period (Nakashima et al, 1998;Miyawaki, 2004;Nakamura et al, 2005). The prevalence of this method was based on thinking that mature, climax forest, most of which had been lost by drastic urbanization in Japan during 1950-60s, should be conserved and restored (Morimoto et al, 2006). Initial assessment indicated success of this restoration method in terms of vegetation cover, as a result of rapid tree growth to the height of 9-11 m 15 years after planting (Murata and Komaki, 2001).…”

“…Therefore, to evaluate the success of natural forest restoration, various parameters of forest structure should be measured, including not only aggregate measures such as forest height and vegetation cover, but also species composition and vertical structure (Rebele and Lehmann, 2002;Marziliano et al, 2013). Monitoring forest dynamics such as tree growth, mortality, and recruitment are also important for future adaptive management and strategies for long-term sustainability (Robinson and Handel, 2000;Morimoto et al, 2006;Oldfield et al, 2013). In addition, changes in forest structure need to be compared with that of reference sites to evaluate the level of restoration success (Hobbs and Norton, 1996;Ruiz-Jaén and Aide, 2006).…”