Table 1. Annual nation-wide statistics depicting the incidence of registered occurrences of marine pollution between 1969 through 1974. “I” denotes pollution cases related to petroleum product (oil); “II” indicates other types of pollution unrelated to oil; “T” denotes sum total of I and II. Figures in parentheses show the number of red tide outbreaks. Data for the southwest sea areas is that compiled after reversion of Okinawa to Japan in 1972 (May 15th).

Table 2. Frequency of samples exceeding the environmental quality standards for total mercury according to geographical region in Japan.

Table 3. Regions which Require(d) Sediment Removal Operation as a Countermeasure of Mercury Pollution.

Table 4. Execution of self-imposed control upon the taking of fish polluted with PCBs.

Data from the Fisheries Agency. Geographic regions marked with an asterisk denote those where self-imposed control has resulted from prefectural surveys.

Table 5. Results of a nation-wide survey on PCB pollution in water, 1972.

Data from Environmental Agency

Table 6. Results of a Nation-wide Survey on the Quantities of PCBs in Sediments. (1972)

Data from the Environment Agency. Bracketed “A” are those areas where PCB concentrations exceeding 100 ppm have been found; “B” denotes those areas where concentrations were 50 to 100 ppm.

Table 7. Regulations on the Use of Agricultural Chemicals (As of Jan 15, 1975)

Data from the Environment Agency

Table 8. Changes in yields of some major fisheries (1960, 1965, 1970, 1973).

Data from the “Production of Fisheries and Aquaculture Yearbook,” 1974.
Superscript “1” denotes mariculture of oyster, laver (Porphyra), pearls, and yellowtail;
“2” denotes rivers and lakes.

Table 9. Damages to Cultured Laver (“nori”) Caused by Oil Pollution in Tokyo Bay (1967–1972).

Data from the Environmental Agency.

Table 10. Pollution Trends in the Seto Inland Sea During the Past Several Decades

Data from Governors' Conference on Environmental Protection. Values represent means of all measurements taken during water quality survey in the Seto Inland Sea.

Table 11. Water Quality of the Major Industrial Areas in the Region of the Seto Inland Sea.¹⁾

1) Data from the Environment Agency

2) Average yearly value

3) Value in 1971

4) Value in 1967

Table 12. Surveillance Results of Environmental Quality Guidelines in the Seto Inland Sea and Nation-wide.

[a] Incidences at which guidelines were exceeded for health categories.

[b] Percentage of those areas which conformed to the environmental quality guidelines.

Data from the Environmental Agency

Table 13. Percentages of COD Area Distribution in the Seto Inland Sea (1972 to 1974).

Data from Environmental Agency. Values were taken in May of each year.

Table 14. Red tide plankters which appeared in the Seto Inland Sea during outbreaks in 1974.

Table 15. Localities of the Seto Inland Sea where concentrations of PCBs detected in fish exceeded the allowable limit of 3 ppm.

Data from an investigation of the actual state of PCB pollution, conducted by the Environmental Agency and Fisheries Agency in 1972.

Table 16. Pollution Sources of Mercury and its Environmental Levels in the Seto Island Sea

I - Mercury concentration lower than guideline level (0.5 ppm)
II - Mercury concentration exceeding guideline level

[Data from Environmental Agency]

Table 17. Average Values of Heavy Metals in Oysters From Hiroshima Prefecture (from 1968 to 1972).

Table 18. Area of Reclaimed Land in the Seto Inland Sea According to Prefecture (1955–1969).

Table 19. Area of Reclaimed Land in the Seto Inland Sea According to Zone. Projected area of reclamation as of Dec 1, 1971.

Table 20. Coastline Utilization of the Seto Inland Sea (1974)

Data from the Environmental Agency

Table 21. Production of Major Fishery Resources in the Seto Inland Sea (1972).

* billion sheets
Statistics from the Ministry of Agriculture and Forestry

FIG. 1

FIG. 2

FIG. 3. OUTBREAKS OF MARINE POLLUTION CLASSIFIED ACCORDING TO POLLUTION SOURCE AND TYPE. STIPPLED AREAS OF OUTER RING INDICATE OIL-RELATED POLLUTION; UNSTIPPLED AREAS DENOTE POLLUTION UNRELATED TO PETROLEUM. (1974) [FROM THE MARITIME SAFETY WHITE PAPER, 1975].

FIG. 4. THE STATE OF DISPOSAL OF INDUSTRIAL WASTES BY MEANS OF DUMPING VESSELS (1974). NUMERALS ARE EXPRESSED IN UNITS OF ONE THOUSAND TONS. AMOUNTS OF INDUSTRIAL WASTES USED FOR LAND RECLAMATION ARE CITED IN CERTAIN CASES. [FROM THE MARITIME SAFETY WHITE PAPER, 1975].

FIG.5

FIG. 6

FIG. 7. MAP ILLUSTRATING WATER DEPTH OF TOKYO BAY AND SURROUNDING GEOGRAPHICAL FEATURES.

FIG. 8. DIAGRAMMATIC REPRESENTATION OF THE PRESENT STATE OF RECLAMATION WORKS ALONG THE COAST OF KAWASAKI, TOKYO AND CHIBA. YEARS DURING WHICH WORK WAS CONDUCTED IS DENOTED BY CROSS-SECTIONED AREA (1951–1960), HORIZONTAL LINES (1961–1965), DIAGONAL SOLID LINES (1966–1970), AND DIAGONAL STIPPLED LINES (1971–1973); BLANK BORDERED AREAS ARE THOSE UNDER CONSTRUCTION. AREAS ENCLOSED BY DOTTED LINES REPRESENT DREDGED AREAS. OTHER SYMBOLS INCLUDE THOSE FOR BREAKWATER , SHORE PROTECTION WORKS , QUAY OR BREAKWATER , WOODEN STOCKADE . From the Tokyo Metropolitan Harbor Office, March, 1974.

FIG. 9-1

FIG. 9-2

FIG. 10-1

FIG. 10-2

FIG. 11-1

S A M P L I N G S T A T I O N D E S I G N A T I O N

FIG. 11-2

S A M P L I N G S T A T I O N D E S I G N A T I O N

FIG. 11-3

FIG. 12

FIG. 13

FIG. 14-1

FIG. 14 - 2. SEASONAL VARIATION IN THE DENSITY OF RED TIDE ORGANISMS IN TOKYO BAY. A RED TIDE CONDITION IS DENOTED BY THE DARKENED AREAS; THE NORMAL CONDITION IS GIVEN BY DIAGONAL LINES.

FIG. 15

FIG. 16

FIG. 17

FIG. 18-1

FIG. 18-2

FIG. 19

FIG. 20-1

FIG. 20-2

FIG. 21-1

FIG. 21-2

FIG. 21-3

FIG. 22(a)

FIG. 22(b)

FIG. 22(c)

FIG. 22(d)

FIG. 22(e)

FIG. 23(a)

FIG. 23(b)

FIG. 24-1

FIG. 24-2

FIG. 24-3

FIG. 24-4

FIG. 24-5

FIG. 25

FIG. 26

FIG. 27

FIG. 28

FIG. 29

FIG. 30

FIG. 31. CASES OF OIL POLLUTION IN DIFFERENT AREAS OF THE SETO INLAND SEA. From “The Present Situation of Maritime Safety, 1974”, by the Maritime Safety Agency.

FIG. 32. CASES OF OIL POLLUTION ACCORDING TO VESSEL DISTINCTION. From “The Present Situation of Maritime Safety, 1974”, by the Maritime Safety Agency.

FIG. 33. EEL GRASS (“amamo,” Zostera) ZONES PRIOR TO 1965 IN DIFFERENT REGIONS OF THE SETO INLAND SEA, AND THEIR REDUCTION RATES UP TO 1965. BLACK - PROPORTION OF REMAINING AREA; WHITE - PROPORTION OF VANISHED AREA. NUMBERS SHOW THE AREA IN HECTARES PRIOR TO 1965. Data from the Southwest Regional Fisheries Research Laboratory.

FIG. 34. EEL GRASS (“amamo,” Zostera) ZONES PRIOR TO 1965 IN DIFFERENT REGIONS OF THE SETO INLAND SEA, AND THEIR REDUCTION RATES BETWEEN THE YEARS 1965 TO 1971. SYMBOLIC REPRESENTATION AND NUMERALS ARE THE SAME AS GIVEN IN FIG. 33. Data from the Southwest Regional Fisheries Research Laboratory.

FIG. 35

FIG. 36

FIG. 37. CHANGES IN THE AMOUNT OF MAJOR FISHERIES PRODUCTS IN THE SETO INLAND SEA. Data from the Fishery and Aquaculture Yearbook of the Ministry of Agriculture and Forestry for 1953, and the Fisheries Statistic Table in the Seto Inland Sea from the Chugoku-Shikoku Agricultural Administration Bureau for the years 1958 to 1973.

FIG. 38. CHANGES IN THE AMOUNT OF MAJOR MARINE PRODUCTS (MARINE ANIMALS, SHELLFISH, AND SEAWEEDS) IN THE SETO INLAND SEA. Data from the Fishery and Aquaculture Yearbook of the Ministry of Agriculture and Forestry for 1953, and the Fisheries Statistic Table in the Seto Inland Sea from the Chugoku-Shikoku Agricultural Administration Bureau for the years 1958 to 1973.

FIG. 39. CHANGES IN THE CATCHES OF DIFFERENT FISHES. Data from the Fishery and Aquaculture Yearbook of the Ministry of Agriculture and Forestry for 1953, and the Fisheries Statistic Table in the Seto Inland Sea from the Chugoku-Shikoku Agricultural Administration Bureau for the years 1958 to 1973.

FIG. 40. AREAS OF THE SETO INLAND SEA WHICH HAVE BEEN DESIGNATED AS THOSE WHERE RECLAMATION WORK SHOULD BE AVOIDED. Data from the Environmental Agency.

Supplementary FIG. I

Supplementary FIG. II

Supplementary FIG. III