Policy Bureau

TOWARD CREATING and INHERITING BETTER ENVIRONMENT

Biodiversity Conservation in Infrastructure Development

  • Japanese


  • A main action example for biodiversity conservation activities
  • ■Nature-Oriented River Works

  • In the situation of necessary construction of river infrastructures, instead of using conventional methodologies of molding banks or shores with concrete materials, new methodologies are increasingly used to conserve, restore and create good conditions for wetland, wild plants so as to trigger nature’s own dynamism and mechanism. These methodologies will contribute to the restoration and creation of natural habitats where wildlife breed, grow and live.
  • When doing construction to widen a cross-section of the Umeda River, a part of the Tsurumi River system in Yokohama, Kanagawa, to prevent fl ooding,(planned capacity to increase from 6m3/s→35m3/s), the bend in the river that followed the slope of the mountain was retained, and rapids and pools were formed where fi sh can live, and waterside vegetation is encouraged to grow where the insects fi sh eat are supplied and fry can hide.。
  • Umeda River before repairs (1992)   Umeda River after repairs (2007)
     
  • ■River Construction That Provides Habitat for Storks

  • Storks were abundant all over Japan before 1950s, but since then, due to rapid economic development and adverse impact by heavy use of agricultural chemicals, they have become extinct in the wild. Maruyama River area, where was the last habitat of wild storks lived, suffered tremendous damage by a great fl ood in 2004. After the flood, the stakeholders pursued restoration of the habitats for storks as well as enhancement of the safety against floods. While dredging the bottom of river to increase the fl ow rate, we created wetland areas with shallow water,increasing the size of wetland areas by about 50%. We have been providing precious feeding sites for storks since they were released in the wild through the Stork Recovery Program in 2005.
  • River
  • ■Conservation and Restoration of Familiar Habitats (Showa Kinen Park)

  • The site of Showa Kinen Park was originally Tachikawa US Military Base moved from old Japanese Military and returned to Japan in 1977. The picture in 1981 looks wild land with little natural environment. A vast green space has been created in about 20 years. This example of nature restoration in big cities is unusual effort.
  • The park has constantly monitored those environment conditions and has valuable data how to restore urban ecosystem.
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  • ■Greening Area System/ What Nagoya City is doing

  • Despite the fact that Nagoya City created 420ha of new park and planted trees in public spaces from 1990 to 2005, the city as a whole lost 1,643ha of total greenery during the same period, due to land being converted into residential areas and other private undertakings. The city decided to designate 93% of the city area into a "greening area". By October 2009, about a year after measures began, more than 50ha had been recovered. At present, there are green spaces such as roof gardens made with biodiversity in mind, and greenery on places one wouldn’t usually think of, such as small shops with lawns, etc. By requiring greenery in this new system, there are great expectations that the greening of cities can contribute to conservation of biodiversity.
  • GreeningGreening
  • ■Environmental Recovery through Sewer Construction: Restoration to Clean Rivers

  • During Japan’s rapid economic development period, water pollution in public water areas such as rivers, lakes and coastal seas drastically worsened due to incremental inflows from both domestic and industrial discharges together with the continues concentration of population and industries into large cities such as Tokyo.
  • Since 1965, Tama River experienced water pollution evidenced by muchhigher-than-standard levels of biochemical oxygen demand (BOD) that has caused serious impacts on ecosystems and riparian landscapes. Since then,basin-wide sewer networks have been developed. As water quality has improved, freshwater fi sh like Ayu (sweetfi sh) have gradually returned. By developing sewer systems, we are contributing to cleaning wastewater from households, industries and farmlands, and to restoring ecosystems and biodiversity.
  • EnvironmentalEnvironmental
  • Environmental
  • ■Harbor Projects Contributing to Ecosystem Preservation~Restoration of nature at Mikawa Bay~

  • Surrounded by Chita and Atsumi Peninsulas, Mikawa Bay is an enclosed area with a small mouth. This means the poor water fl ow to and from the open sea makes it easier for pollutants to accumulate, causing concerns.
  • Aiming to restore the clean, blue seawater and create a rich environment,high-quality sediment dredged from the site of the Nakayama Navigation Channel Improvement Project were brought in to cover sludge in the bay,reducing nitrogen and phosphorus released into the sea and improving the quality of water and bottom sediment. From 1999 to 2004, sand-capping works were carried out and tidal fl ats and seaweed beds made at 39 locations in the bay (a total of about 620ha).
  • Restoring mudflats and seaweed beds lost due to past development led to ecosystem recovery, and many diverse sea creatures are now observed in the sand-capped areas.
  • HarborHarbor
  • ■Seaweed Bed Development in conjunction with Construction of Chubu International Airport

  • Centrair, opened in February 2005 as an airport with the capacity for aroundthe-clock operations on a man-made island in Aichi prefecture, is one of main gateway for the sky connecting domestic network to international network.
  • Note) “ Centrair” is nickname of Chubu International Airport. It is derived from “ Central Japan” (Chubu region) and “ Airport”.
  • Centrair promotes environmental-conscious management as its basic policies,and has been implementing various measures for environmental conservation since its construction.
  • The seawall around airport island is one of measures to reduce environmental impact. It is gently sloped, covered with natural stones, to attract a diversity of marine life. Especially at the west and south side of the seawall that has shallow areas in 4m depth with 10m wide, Centrair transplanted various species of seaweeds such as Ecklonia cava and Eisenia bicyclis to develop seaweed bed. Now, 5 years have past since its construction, the seawall is thickly covered with natural seaweeds such as Undaria pinnatifida,Sargassum horneri as well as transplanted seaweeds, and Greenling, black rockfi sh, and shore swimming crab can be observed in the area.
  • Centrair gathers the seaweed (Sargassum horneri) which is rich in nutrition and good for health together with local fi shermen, and sells it as specialty food in the region.
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  • Seaweed
  • ■Eco-Road~A Road Built with Consideration for Nature~

  • Central Nippon Expressway Company Limited (NEXCO-Central) is currently constructing the New Tomei and New Meishin Expressways to alleviate the traffi c congestion on the existing Tomei and Meishin Expressways and make a signifi cant contribution to Japan’s industrial, cultural and socioeconomic activities. From the planning and design stages to full-scale operation, we strive to conserve biodiversity along expressways based on the concept that is “Eco-Road”. Also we avoid and reduce negative impacts on the ecosystem while creating a new natural habitat for wildlife as such.
  • For example, we have adopted a new technology to reduce adverse effects to rare fauna and fl ora and the natural environment. We also are using seedlings of local species to form a “Green Network” in conjunction with green area along the expressway. Thus, we are helping to reduce the greenhouse gases and create wildlife habitats.
  • 緑化地域制度/名古屋市の取組11
  • 緑化地域制度/名古屋市の取組21
  • ■Global Mapping Project

  • Global Map is basic geospatial datasets covering the whole land area of the globe with consistent specifi cations. Global Map consists of 8 thematic layers (transportation, boundary, drainage, population center, elevation, vegetation,land cover, land use), which shows natural environment and human activities.
  • The data is assumed to be updated in every 5 years in order to better monitor and detect the change of global environment. Spatial distribution of biodiversity is visualized by overlapping information about habitat of creatures with Global Map. It will contribute to international activities and formulation of measurements for the conservation of biodiversity. Japanese Government has led the Global Mapping Project and currently National Mapping Organizations of 180 countries and regions are participating in the project.
  • Global
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