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National Survey
Vegetation Naturalness Survey / Vegetation Survey
Survey Sequence and Effective Years
(All years are fiscal years)
data Result list (Japanese only except )
1st survey
1973
  Actual Vegetation Map (1:200,000) (every all pref.)
Vegetation Naturalness Map (1:200,000) (every all pref.)
National State of Nature Survey Report
2nd survey
1979
Outline of the National Survey on the Natural Environment (Vegetation, Lakes and Rivers)
Actual Vegetation Map (1:50,000)
Report of Vegetation Survey -gathered by each prefectures (45vols)-
Report of Vegetation Survey
Manual of Legends for Actual Vegetation map (1:50,000)
3rd survey
1983-1986
Actual Vegetation Map (1:50,000)
Report of Vegetation Survey -gathered by each prefectures (44vols)-
Report of Vegetation Survey
Actual Vegetation Map (1:3,000,000)
4th survey
1989-1992
  Report of Vegetation Survey Actual Vegetation Map (1:2,500,000)
Vegetation Naturalness Map (1:2,500,000)
Actual Vegetation Changes Map (1:50,000)
Actual Vegetation Map using Vegetation raster data (about 1km x 1km)
Vegetation Naturalness Map (every all pref.)
List of Legend for Actual Vegetation Map
Vegetation raster data (about 1km x 1km)
5th survey
1995-1999
Actual Vegetation Changes Map (1:50,000)
Actual Vegetation Map (1:2,500,000)
Vegetation Naturalness Map (1:2,500,000)
Report of Vegetation Survey
Manual of Legends for Actual Vegetation map (1:50,000)
Report of Vegetation survey on satellite image data analysis
Vegetation raster data (about 1km x 1km)
6th-7th survey
6th 1999-2004
7th 2005-
  6th, 7th Vegetation survey web page [Japanese web page]
How To Read This Display

When reproduction and distribution this map free of charge, please make acknowledgments as follows:
"This distribution map was generated by the Environment Agency's(*) 3rd Vegetation Survey Internet Site."
Distribution for a fee requires the Environment Agency's(*) Permission

  1. Survey Objectives
 Vegetation exhibits diverse features from region to region. This diversity is the result of evolution and adaptations according to the history, climate, topography and geology of each region, as well as the interactions among vegetation and other organisms, including man. When we propose to do things that affect the natural environment, approaches and techniques appropriate to each region's special characteristics can be ascertained from examining its vegetation.

 A vegetation map showing plant community units classified according to plant sociology is very useful as a diagnostic map for national land use planning, regional development and industrial zoning. It also has prescriptive values for designing ecologically sound environmental protection, restoration and promotion measures. It is an indispensable resource for the development of a master plan for protecting and developing each species.

 This survey was made with the aim of producing a national vegetation map that would show the status of vegetation throughout the country and serve the purposes and goals mentioned above.
  2. Survey Content and Methods
 The prefectures were asked to undertake the 1st through the 5th surveys. In each prefecture, interpretation of aerial photographs and on-site surveys were done and an actual vegetation map on a scale of 1: 50,000 was made. An actual vagetation map was complied in the 1st survey and then a map on a scale of 1: 200,000 was printed for each prefecture.

 The 2nd and 3rd surveys continued looking into the state of the country's vegetation in more detail, aiming to produce a map on a scale of 1: 50,000 that would be helpful in planning at the regional and local levels. The 2nd and 3rd surveys each covered about half of the country. By 1987, 1,293 copies of the 1: 50,000 actual vegetation map were printed and distributed.

 To assess the state of vegetation from a national perspective, survey results were totaled by coding them using the small circle method (a 5mm-diameter circle centered on a grid map to highlight predominating communities) using the Grid Square System (Standard Area Grid. also called the 3rd grid. About 1km X 1km). In this way, present state of vegetation and Vegetation Naturalness were shown on tables and maps.

 In the 4th survey and 5th survey satellite images were used for the first time to get firm data on changes over the years. Satellite image data (from LANDSAT MSS, TM, etc) at two points in time (old & new) was analyzed to determine vegetation changes. Then surveys on the ground were made in each prefecture based on the results. In this way up-to-date information could be produced in a short span of time. The information gained with this method on changes in the nation's vegetation was used to update the 1:50,000 vegetation map built up from the 2nd and 3rd surveys. A revised map of vegetation change on the same scale was prepared. An actual vegetation map and a vegetation naturalness map were also made on a scale of 1: 2,500,000.
  3. Survey Results
 The 1st survey set out to put together a vegetation map, using plant sociological methods, for the whole country and, on the basis of the map, to make judgements as to the extent of human modification (Vegetation Naturalness) of the land. An index was devised, according to "the degree of human disturbance " to rank environments from those wholly in their natural state or nearly so to those with very little original nature remaining. The ten ranks of "Vegetation Naturalness" are shown as follows:
Criteria of Vegetation Naturalness Classification (Degree of human disturbance of vegetation)
  Vegetation Naturalness
10 Natural vegetation of grassland and moorland.
9 Natural vegetation of forest.
8 Substitutional vegetation close to natural vegetation of forest.
7 Substitutional vegetation of secondary forest.
6 Planted forest.
5 Substitutional vegetation of high profile grassland.
4 Substitutional vegetation of low profile grassland.
3 Fruit orchards, mulberry plantations, tea gardens, and other horticultural areas.
2 Paddies, fields, and other arable land, residential area with abundant trees.
1 Urban land, developed tracts, and other zones where plant life is virtually nonexistent.

 The 2nd and 3rd surveys resulted in production of a nationwide "1: 50,000 actual vegetation map." There is no other example in the world of a map covering an entire country on a 1:50,000 scale. The 4th survey and 5th survey corrected the original map for changes and produced the "1: 50,000 actual vegetation changes map."

 The plant sociological community classifications (legend) shown by the map clearly reveal the diversity of plants in Japan. When plants unique to particular regions are added to the nationwide standard plant digest, the total reaches 766 communities.

 When the results are summarized in the ten-rank classification according to the amount of human influence on the natural environment, forests (ranks 9 - 6) cover some 250,000 square kilometers, or 67.3% of the country. Natural forests plus natural grasslands have shrunk to less than one-fifth, 19.0%, of the country.

 Between the 3rd and 5th surveys, the broad category of forests as a whole (ranks 9 - 6) shrank. Since affronted areas (rank 6) did not diminish, the inference is that the shrinkage in total forests came as a result of loss of natural and second-growth forests (ranks 9 - 7). Also, there was essentially no change in the share of cultivated farmland and cities.


Changes in Vegetation Naturalness over Time
Vegetation Naturalness Survey
1st National Survey on the Natural Environment
2nd & 3rd National Survey on the Natural Environment
4th National Survey on the Natural Environment
5th National Survey on the Natural Environment
Grid Count
Component Ratio
Grid Count
Component Ratio
Grid Count
Component Ratio
Grid Count
Component Ratio
Natural Grasslands (rank 10)
3,260
0.9
4,038
1.1
4,011
1.1
3,993
1.1
Forests (ranks 9-6) (*1)
244,994
68.0
248,538
68.2
247,229
67.8
245,376
67.3
Natural & Secondary Forests (ranks 9-7)
169,854
47.1
157,509
43.2
155,157
42.6
153,962
42.2
Afforested Areas (rank 6)
75,140
20.9
91,029
25.0
92,072
25.3
91,414
25.1
Secondary Grasslands (ranks 5&4)
12,876
3.6
11,676
3.2
12,124
3.3
13,159
3.6
Cultivated Areas (ranks 3&2)
83,030
23.0
77,412
21.3
77,701
21.3
78,052
21.4
Cities and Towns (ranks 2&1) (*2)
15,597
4.3
21,172
5.8
21,847
6.0
22,430
6.2
Other (areas bare of vegetation; category unknown))
602
0.2
1,464
0.4
1,487
0.4
1,490
0.4
All Japan (*3)
360,359
100.0
364,300
100.0
364,399
100.0
364,500
100.0
Open Seas
0
-
4,170
-
4,211
-
4,227
-
All Japan
360,359
-
368,470
-
368,610
-
368,727
-

*1 "Forests" include "natural & secondary forests" and "afforested areas".
*2 Includes "greenery-rich residential areas" (rank 2) in cities and towns
*3 Open seas excluded

 Open seas were not included in the 1st survey so when comparing current survey results, component ratios were computed and gains or losses reported for national land area excluding the seas.

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*) The organization was changed to the Ministry of Environment in 2000.