[Asahi Kasei Homes Co., Ltd.] Asahi Kasei Homes, Sekisui House, and Daiwa House Industry collaborate to demonstrate the effectiveness and synergy of Nature Positive through urban greening using native tree species
*Asahi Kasei Homes Co., Ltd.*
Press release: September 4, 2024
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Asahi Kasei Homes, Sekisui House, and Daiwa House Industry collaborate to demonstrate the effectiveness and synergy of Nature Positive through urban greening using native tree species
*~Promoting urban biodiversity conservation activities using native tree species through collaboration between three companies, a first in the housing industry~*
Asahi Kasei Homes Co., Ltd. (Head office: Chiyoda-ku, Tokyo, Representative Director and President: Kawabata
Fumitoshi (hereinafter referred to as “Asahi Kasei Homes”), Sekisui House Co., Ltd. (Head office: Kita-ku, Osaka, Representative Director and President: Nakai)
Yoshihiro (hereinafter referred to as “Sekisui House”), Daiwa House Industry Co., Ltd. (Head office: Kita-ku, Osaka, Representative Director and President: Yoshii)
Keiichi (hereinafter referred to as “Daiwa House Industry”) (hereinafter referred to as “three companies”) is working on urban greening with each housing manufacturer focusing on native tree species in order to achieve the international goal of 2030 Nature Positive*1. In order to demonstrate the synergy of biodiversity conservation effect by
Based on analysis by Think Nature Co., Ltd., the three companies collaborated to evaluate the effectiveness of nature positive initiatives in cities. This is the first time*2 that a collaborative evaluation between housing manufacturers has been conducted in biodiversity conservation activities.
The analysis based on this data on planted tree species shows that the unique efforts of each of the three companies, which focus on native tree species, complement each other’s individual contributions ecologically and contribute to the effectiveness of Nature Positive. Synergies were made clear. Based on these results, the three companies, as housing manufacturers that supply many homes and buildings in urban areas, are promoting planting proposals that focus on native tree species throughout the housing and real estate industry to improve biodiversity. We will contribute to accelerating
conservation efforts.
* Analysis summary 1) The three companies have planted various tree species with different characteristics, which has increased the richness of biodiversity compared to individual companies.
2) Effectively regenerate multifaceted elements of biodiversity by planting trees with each company’s unique concept*
The three companies focused on native tree species, recognizing that biodiversity not only in nature reserves and satoyama-like
environments, but also in the cities where we live, is important from the perspective of the well-being of residents. We propose unique urban and garden planning. At Asahi Kasei Homes, we plant trees of various heights (hierarchical structure) to contribute to the townscape and create a small forest in the city. Daiwa House Industry plans to plant more than 50% native tree species in real estate for various uses in consideration of the local ecosystem network. We are engaged in greening activities based on the concept of “Connecting Greenery!”
This time, by visualizing and integrating data on the number of trees and tree species from three companies in the metropolitan area (Tokyo, Saitama, Chiba, and Kanagawa), we will examine the effects of the three companies’ different efforts on urban biodiversity conservation. We analyzed *3.
1) The three companies have planted various tree species with different characteristics, which has increased the richness of biodiversity compared to individual companies.
This analysis revealed that the three companies have planted a variety of different tree species through their respective initiatives, resulting in an increase in the richness of biodiversity compared to individual companies.
When we verified the number of individuals of each species of trees planted by the three companies, we found that if we combined the tree species planted by the three companies, it would amount to
approximately 430,000 trees of 350 different species in a year, which was higher than the individual company that had the largest number of species. It was also found that the number of species was
approximately 10% higher, confirming the importance of the three companies’ greening activities in urban areas and their high potential for nature-positive effects.
Furthermore, this data is expressed in a “species ranking curve with respect to population size”*4, which indicates the number of species and the level of evenness of species, and is used as an indicator for biodiversity assessment. The graph obtained by integrating the three companies has a gentle slope, which clearly indicates that various species coexist and there is a rich diversity of planted tree species. Planting distribution map in the Tokyo metropolitan area by Asahi Kasei Homes, Sekisui House, and Daiwa House Industry
Ranking curve of planted tree species based on species population data of planted tree species
2) Effectively regenerate multifaceted elements of biodiversity by planting trees with each company’s unique concept.
An analysis by Think Nature Co., Ltd. found that three companies are working on planting proposals that focus on native tree species with different concepts, and that they are effective in realizing nature positivity by complementing each other’s multifaceted elements of biodiversity. It was evaluated for its scientific significance as leading to.
Asahi Kasei Homes’ “Machimori” project provides a habitat for creatures such as birds that require shelter and space, Sekisui House’s “Five Trees” plan provides food resources for living creatures, and Daiwa House Industry’s “Midori Greening activities based on the concept of “Let’s Connect!” allow for multifaceted regeneration, as each area has different elements necessary for biodiversity, such as regenerating habitats for living things not only in residential areas but also in surrounding areas. Understood. Through these efforts, it is expected that the regenerated urban green space will further revitalize the connections between living things (food webs).
This collaborative demonstration by the three companies resulted in synergies that effectively regenerated multifaceted elements of biodiversity by promoting planting proposals that focused on native species with each company’s own greening concept. We demonstrated the possibility of co-creation between companies to realize nature positivity.
In response to this result, Asahi Kasei Homes, Sekisui House, and Daiwa House Industry will further increase the effectiveness of Nature Positive by encouraging more companies and organizations to support initiatives centered on native tree species. We will work together on activities to expand our efforts in the real estate industry. ■Comment from Yasuhiro Kubota, Professor, Faculty of Science, University of the Ryukyus, CEO of Think Nature
Information about real estate and house manufacturers’ planting projects, such as “when, where, and how many trees of what kind were planted?” can be called “greening accounting.” This integrated analysis of the three companies is a data analysis related to greening accounting, and quantitatively evaluates the “contribution to biodiversity restoration” brought about by greening business assets. This analysis project is probably the first in the world where visualizing the nature-positive effects of multiple companies’ planting projects can serve as a social signal.
We hope that this will encourage collective action involving more companies and contribute to Target 12 of the Kunming-Montreal Biodiversity Framework: Securing urban green and water-friendly spaces. At the same time, I hope that biodiversity will become a new standard of value in the real estate and housing construction business, and in the context of urban nature positivity, the industry as a whole will see high added value and the creation of new business opportunities.
■About Asahi Kasei Homes’ “Machimori”
“Machimori” utilizes the knowledge of vegetation gained from “Asahi Inochi no Mori,” which has been underway since 2007 at the former factory site of the Asahi Kasei Corporation branch in Fuji City, Shizuoka Prefecture, to plan the external structure of housing. This is a planting method uniquely developed for By combining plants of different heights such as tall trees, medium trees, shrubs, and ground cover plants and planting them on the facade side, we aim to contribute to the richness of the townscape and attract a variety of creatures such as birds and insects. By connecting houses and condominiums equipped with “Machimori” with greenery such as street trees and parks in the city, a richer ecosystem will be fostered and an “ecological network” will be formed throughout the region. We are promoting activities to conserve urban biodiversity.
Townscape: A life rich in greenery is kind to living things. https://www.hebel-haus.com/brand/sustainablestory/machimori/index.html/
The “Five Trees” plan was developed by our company in 2001.
As part of our efforts to conserve biodiversity, this project was started in 2017 as a landscaping project that takes the ecosystem into consideration, with the cooperation of our customers. With the idea that “three trees are for birds and two trees are for butterflies,” we propose garden and town development centered on native tree species that suit the climate of the area. The cumulative number of trees planted since the start of the project has reached 20 million. In 2021, we will build the world’s first quantitative assessment system for urban biodiversity using data on the number, species, and location of trees and biodiversity big data to evaluate the
effectiveness of biodiversity conservation. Published as “Nature Positive Methodology.”
Sekisui House’s “Five Trees” plan
https://www.sekisuihouse.co.jp/gohon_sp/
■About Daiwa House Industry’s greening activities based on the concept of “Connecting Greenery!”
Looking ahead to 2055, the 100th anniversary of our founding, we announced our long-term environmental vision “Challenge ZERO” in fiscal 2016.
2055″ and aims to realize a sustainable society. In fiscal 2022, we will set out specific plans and goals under the “Endless Green Program.”
2026,” and we are also promoting initiatives for biodiversity. As part of this effort, in order to achieve Nature Positive, we are promoting greening activities that use at least 50% native species under the Group’s common greening concept of “Let’s connect greenery!” From April 2022 to 2024. By March 2019, we will aim to increase the area of greenery by 464,000 square meters in consideration of the local ecosystem.
(approximately 9 times the size of Tokyo Dome).
Daiwa House Industry’s efforts to realize nature positivity (released on August 19, 2024)
https://www.daiwahouse.co.jp/about/release/house/20240808144256.html ■Think Nature Co., Ltd.
This is a startup from the University of the Ryukyus, made up of researchers with outstanding achievements in biodiversity science. We support the nature-related businesses of various companies with advanced analysis using distribution data of over 300,000 species of living things covering land and sea around the world and over 150 indicators related to biodiversity and natural capital. Leveraging our unique strengths as experts in biology and ecology, we help companies reduce nature-related risks, increase positive impact, and transform to nature-positive management.
https://think-nature.jp
*1 Nature positive refers to stopping and reversing the loss of biodiversity and putting it on a recovery track.
*2 Asahi Kasei Homes, Sekisui House, Daiwa House Industry research *3 A service that uses a scientific approach using AI and big data to quantify the nature-positive effects that corporate activities have on nature (
https://services.think-nature.jp/gain/ )
*4
The “species ranking curve with respect to population size” indicates the ranking of the proportions of the populations of dominant, common, and rare species, and is a quantitative indicator of biodiversity. Species diversity can be evaluated in terms of species richness (the number of species) and evenness (the evenness of the number of each species in the community). Species diversity can be said to be high if there are a large number of species, and if certain species are evenly distributed rather than concentrated. In a species ranking graph, the horizontal axis shows the ranking of species starting from the species with the largest number of individuals, and the vertical axis shows the ratio of the number of individuals of a species to the total number of individuals.
The simpler the community, where the proportion of some species in the community is large and the dominant species is prominent, the steeper the slope of the species ranking graph will be. On the other hand, in a “biodiversity-rich community” where various species coexist, the slope of the species ranking graph becomes gentler. In this graph, the red symbols and lines are the ranking curves for the planted tree species that integrate the three companies’ planting, and the yellow, green, and light blue are the ranking curves for the planted tree species for each individual company. Compared to the slope of the ranking graph of planted tree species for each individual company, the slope of the species ranking graph for the three companies integrated is gentler, indicating a rich diversity of planted tree species.