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㸱㸬ᨻ⟇ㄢ㢟◊✲㸱㸦36㸧⏕ែ⣔ಖ඲࡟ࡘ࡞ࡀࡿ≀㉁ᚠ⎔ࡢ࠶ࡾ᪉࡟㛵ࡍࡿ◊✲బ⸨♸୍࣭᪩ᕝ࿴⚽࣭Ọ⏣㈗୸࣭ᑿཎ⚞ᖾ 㸧࣭ᒸᮏ㧗ᘯ࣭୐㔛ᑗ୍࣭ᒣཱྀಖᙪ࣭㓇஭㝧୍㑻࣭୰ᮧග✑࣭ᚋ⸨┤ᡂ 㸧࣭௒஭❶㞝 㸧࣭ᐩᒸ඾Ꮚ 㸧࣭బ㔝཭᫓ 㸧࣭ᑠᯇ୍ᘯ 㸧࣭ᅵᒇ೺ྖ 㸧࣭㧗ὠᩥே 㸧࣭㟖㫽Ꮥ୍ 㸧࣭୰㔝ఙ୍ 㸧࣭⛬ᮌ⩏㑥 㸧࣭ᑠᯇⱥྖ 㸧࣭ୖཎ ᾈ 㸧せ⣙⍇⍈†࡛ࡣὶධ㈇Ⲵࡢᢚไ࡟ࡼࡿỈ㉁ࡢᨵၿࡔࡅ࡛ࡣ࡞ࡃࠊ㨶௓㢮➼࡟ࡘ࡞ࡀࡿ≀㉁ᚠ⎔ࢆ෇⁥࡟ࡍࡿࡇ࡜ࡢ㔜せᛶࡀᣦ᦬ࡉࢀ࡚࠸ࡿࠋᮏ◊✲ࡣࠊ†ෆࡢ⏕㣗㣗≀㐃㙐࠾ࡼࡧᚤ⏕≀㣗≀㐃㙐ࡢ≧ἣࢆヲ⣽࡞ㄪᰝ࡟ࡼࡾᢕᥱࡋࠊࣔࢹࣝࢆ⏝࠸࡚㨶㢮㈨※㔞࡜ࡢ㛵㐃࡟ࡘ࠸࡚ゎᯒࡍࡿࡇ࡜࡛ࠊ⏕ែ⣔ಖ඲ࡢほⅬ࠿ࡽᮃࡲࡋ࠸†ෆ≀㉁ᚠ⎔ࡢ࠶ࡾ᪉ࢆᥦ᱌ࡍࡿࡇ
࡜ࢆ┠ⓗ࡜ࡋࡓࠋ⍇⍈†࡟࠾ࡅࡿ᳜≀ࣉࣛࣥࢡࢺࣥࠊື≀ࣉࣛࣥࢡࢺࣥࠊ⣽⳦ࡢ⏕⏘ᛶࢆᐇࡍࡿᡭἲࢆ☜❧ࡋ࡚⍇⍈†Ἀᖏ࡟࠾ࡅࡿ᭷ᶵ≀཰ᨭࢆᴫ⟬ࡋࡓ࡜ࡇࢁࠊୖ఩ࡢᤕ㣗⪅࡬ࡢ᭷ᶵ≀౪⤥ࡣᚤ⏕≀㣗≀㐃㙐ࡼࡾࡶ⏕㣗㣗≀㐃㙐ࡀ༟㉺ࡍࡿ࡜⪃࠼ࡽࢀࡓࠋࡲࡓࠊ㣗≀⥙ࢆⅣ⣲࣭❅⣲Ᏻᐃྠ఩యẚ࡛ㄪᰝࡋࡓ⤖ᯝ࠿ࡽࡣࠊ࢔ࣘࡸ࣍ࣥࣔࣟࢥࡢᡂ㨶ࡀ㣵࡜ࡍࡿື≀ࣉࣛࣥࢡࢺࣥࡣࠊȣP ᮍ‶ࡢ᳜≀ࣉࣛࣥࢡࢺࣥࢆ୺㣗࡟ࡋ࡚࠾ࡾࠊᚤ⏕≀ࡸ኱ᆺ⸴㢮㸦ȣP ௨ୖ㸧ࡣ࡯࡜ࢇ࡝㣗࡭࡞࠸ࡇ࡜ࡀ᫂ࡽ࠿࡟࡞ࡗࡓࠋ≀㉁ᚠ⎔ࡢ෇⁥ࡉ࡟╔┠ࡋࡓ⍇⍈†ࡢ೺඲ᛶࢆホ౯ࡍࡿᣦᶆ࡜ࡋ࡚ࠊձ࿧྾ຠ⋡ࠊղ㌿᥮ຠ⋡ࠊճ⏕≀ࣂࣛࣥࢫࡢ  ࡘࢆᥦ᱌ࡋࠊᣦᶆ㛫ࡢ㛵ಀࢆࣔࢹ࡛ࣝゎᯒࡋࡓ࡜ࡇࢁࠊ㌿᥮ຠ⋡࡜⏕≀ࣂࣛࣥࢫࡢ㛫࡟᭷ព࡞┦㛵ࡀࡳࡽࢀࡓࠋࡇࢀࡽࡢࡇ࡜࠿ࡽࠊື≀ࣉࣛࣥࢡࢺࣥࡀ㣗࡭ࡸࡍ࠸୰ᑠࢧ࢖ࢬࡢ᳜≀ࣉࣛࣥࢡࢺࣥࢆቑࡸࡍࡇ࡜ࡣࠊື
≀ࣉࣛࣥࢡࢺࣥࡢቑຍࢆ㏻ࡌ࡚ࠕ㨶ࡢ㇏࠿ࡉࠖࡢྥୖ࡟ࡘ࡞ࡀࡿࡔࡅ࡛࡞ࡃࠊࠕỈࡢࡁࢀ࠸ࡉࠖ࡟ࡶࡘ࡞ࡀࡿ࡜⪃࠼ࡽࢀࡓࠋࡲࡓࠊ᭷ᶵ≀ࡢศゎᛶࢆᢕᥱࡍࡿᣦᶆ࡟ࡘ࠸᳨࡚ウࡋࡓ࡜ࡇࢁࠊᇵ㣴ᮇ㛫ࢆ  ᪥㛫࡟ᘏ㛗ࡋࡓ %2' ࡸࠊ⢏Ꮚែ᭷ᶵ≀㸦32&㸧ࡢⅣ⣲Ᏻᐃྠ఩యẚࠊ⁐Ꮡែ᭷ᶵ≀㸦'2&㸧ࡢศᏊࢧ࢖ࢬศᕸ࡜࠸ࡗࡓᣦᶆࡀ᭷⏝࡛࠶ࡿ࡜⪃࠼ࡽࢀࡓࠋ
 ࡣࡌࡵ࡟

⎔ࡢ࠶ࡾ᪉ࢆ᳨ウࡍࡿࡇ࡜ࢆ┠ⓗ࡜ࡍࡿࠋලయⓗ࡟ࡣࠊ⏕⍇⍈†࡛ࡣὶධ㈇Ⲵࡢ๐ῶ➼࡟ࡼࡾỈ㉁㸦㏱᫂ᗘࠊ71ࠊ㣗㣗≀㐃㙐࠾ࡼࡧᚤ⏕≀㣗≀㐃㙐ࢆ௓ࡋࡓ᭷ᶵ≀㔞ࢆᢕ

73 ➼㸧ࡣᨵၿࡍࡿ୍᪉࡛ࠊ⁺⋓㔞ࡀῶᑡࡋࡓࡾࠊỈⲡࡀ኱ᥱࡍࡿ࡜࡜ࡶ࡟ࠊ㣗≀⥙ࡢᵓ㐀ࡸ㨶㢮ࡢ㣵㈨※ࢆゎᯒࡋ࡚ࠊ㔞⦾ⱱࡍࡿ࡞࡝ࠊ᪂ࡓ࡞ၥ㢟ࡀ㢧ᅾ໬ࡋ࡚࠸ࡿࠋࡇࡢせᅉ†ෆ࡟࠾ࡅࡿ≀㉁ᚠ⎔ࡢ≧ἣࢆ᫂ࡽ࠿࡟ࡍࡿࠋࡲࡓࠊ㨶㢮࡜ࡋ࡚ࠊ†ෆ࡟࠾ࡅࡿ≀㉁ᚠ⎔ࡢᵝ┦ࡀ኱ࡁࡃኚ໬ࡋ࡚ࡁ

➼ࢆ⪃៖࡛ࡁࡿỈ≀㉁ᚠ⎔ࣔࢹࣝࢆᵓ⠏ࡋࠊ⍇⍈†ࡢ೺඲ࡓࡇ࡜ࡀᣦ᦬ࡉࢀ࡚࠸ࡿ㸦⁠㈡┴࣭ி㒔ᗓࠊ㸧ࠋලయᛶࢆホ౯ࡍࡿᡭἲࢆᵓ⠏ࡍࡿࠋᮏ✏ࡣ  ࡘࡢ❶࡛ᵓᡂࡉࢀ

ⓗ࡟ࡣࠊ᳜≀ࣉࣛࣥࢡࢺࣥ࠿ࡽື≀ࣉࣛࣥࢡࢺࣥࠊ㨶௓㢮࡚࠾ࡾࠊྛ❶ࡢᴫせ࠾ࡼࡧ❶㛫ࡢ㛵ಀࡣ௨ୗࡢ㏻ࡾ࡛࠶ࡿ

࡟ࡘ࡞ࡀࡿ≀㉁ᚠ⎔ࡀ⁫ࡾࠊ᭷ᶵ≀ࡸᰤ㣴ࡀ㐺ษ࡟ୖ఩ࡢ㸦ᅗ 㸧ࠋ⏕ែ⣔࡟㌿㏦ࡉࢀ࡚࠸࡞࠸ࡇ࡜ࡀ⪃࠼ࡽࢀࡿࠋࡍ࡞ࢃࡕࠊ➨  ❶㸸≀㉁ᚠ⎔ホ౯ᡭἲࡢᵓ⠏

ὶධ㈇Ⲵࢆᢚไࡋ࡚†ෆࡢ≀㉁㔞ࢆ๐ῶࡍࡿࡔࡅ࡛ࡣ࡞≀㉁ᚠ⎔ࡢ෇⁥ࡉࢆ⾲ࡍᣦᶆࢆᥦ᱌ࡍࡿ࡜࡜ࡶ࡟ࠊ➨ࡃࠊ㨶௓㢮➼࡟ࡘ࡞ࡀࡿ≀㉁ᚠ⎔ࢆ෇⁥࡟ࡋ࡚ࠊⰋዲ࡞Ỉ࣭ ❶ࡢㄪᰝ⤖ᯝࢆ㋃ࡲ࠼ࠊ ✀㢮ࡢࣔࢹࣝࢆ⏝࠸ࡓྛ✀㉁࡜㨶௓㢮ࡢ㈨※㔞ࡢᨵၿࡢ୧❧ࢆᅗࡿࡇ࡜ࡀồࡵࡽࢀᣦᶆࡢゎᯒࢆ⾜࠺ࠋࣔࢹࣝ࡜ࡋ࡚ࡣࠊࠕ㣗≀㐃㙐ࣔࢹ࡚ࣝࠖ࠸ࡿࠋ࠾ࡼࡧࠕ⍇⍈†ὶᇦỈ≀㉁ᚠ⎔ࣔࢹࣝࠖࢆᵓ⠏࣭ᨵⰋࡋࠊ

⍇⍈†ὶᇦࡢ≀㉁ᚠ⎔ࡢ≧ἣ࡟ࡘ࠸࡚ࡣࠊ㏆ᖺ࡛ࡣ†ෆᣦᶆ㛫ࡢ㛵ಀ࠾ࡼࡧ⏕ែ⣔ಖ඲࡟ࡘ࡞ࡀࡿ≀㉁ᚠ⎔ࡢホࡢ୍ḟ⏕⏘㔞ࡸ஧ḟ⏕⏘㔞ࡢ⌧≧ホ౯ࡀ࡞ࡉࢀ࡚࠸࡞࠸ࠋ

౯ᡭἲ࡟ࡘ࠸᳨࡚ウࡍࡿࠋࡲࡓࠊᚤ⏕≀ࡀ㉳ᅉ࡜࡞ࡿᚤ⏕≀㣗≀㐃㙐࡟ࡘ࠸࡚ࡶࠊ⌧➨  ❶㸸Ἀᖏࡢ㣗≀⥙ᵓ㐀࠿ࡽࡳࡓ㨶㢮࡬ࡢ㣵㈨※ホ౯≧ᢕᥱࡀ୙༑ศ࡛࠶ࡗࡓࠋࡑࡇ࡛ᮏ◊✲࡛ࡣࠊ†ෆࡢ⏕㣗ࣉࣛࣥࢡࢺࣥ㣗㨶㸦࣍ࣥࣔࣟࢥ➼㸧࡬ࡢ㣵⏕≀ࡢᙳ㡪ࢆ㣗≀㐃㙐࠾ࡼࡧᚤ⏕≀㣗≀㐃㙐ࡢ≧ἣࢆヲ⣽࡞ㄪᰝ࡟ࡼホ౯ࡍࡿࡓࡵࠊᏳᐃྠ఩యẚศᯒ࡛Ἀᖏࡢ㣗≀⥙ᵓ㐀ࢆゎࡾᢕᥱࡋࠊࣔࢹࣝࢆ⏝࠸࡚㨶㢮㈨※㔞࡜ࡢ㛵㐃࡟ࡘ࠸࡚ゎᯒࡋࠊ㨶ࡀྛ㣵⏕≀ࢆࡑࢀࡒࢀ࡝ࢇ࡞๭ྜ࡛㣗࡭࡚࠸ࡿࡢ

ᯒࡍࡿࡇ࡜࡛ࠊ⏕ែ⣔ಖ඲ࡢほⅬ࠿ࡽᮃࡲࡋ࠸†ෆ≀㉁ᚠ

࠿ࢆᢕᥱࡍࡿ㸦⏕㣗㣗≀㐃㙐ࢆᑐ㇟࡜ࡍࡿ㸧ࠋ1㸧ඖ࣭⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮㸦⌧㸸†໭⎔ቃ஦ົᡤ㸧  2㸧⁠㈡┴❧኱Ꮫ  3㸧ᅜ❧⎔ቃ◊✲ᡤ  4㸧ி㒔኱Ꮫ⏕ែᏛ◊✲ࢭࣥࢱ࣮ 
5㸧ඖ࣭ி㒔኱Ꮫ⏕ែᏛ◊✲ࢭࣥࢱ࣮㸦⌧㸸Ⲉᇛ┴㟘ࢣᾆ⎔ቃ⛉Ꮫࢭࣥࢱ࣮㸧  6㸧᫂἞኱Ꮫ  7㸧ࣃࢩࣇ࢕ࢵࢡࢥࣥࢧࣝࢱࣥࢶ(ᰴ)⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮◊✲ሗ࿌᭩➨ 16 ྕ55➨  ❶㸸⍇⍈†࡟࠾ࡅࡿ᭷ᶵ≀཰ᨭࡢᢕᥱ࡟㛵ࡍࡿ◊✲≀㉁ᚠ⎔ࡢࣇ࣮ࣟࢆ

࠿ࠋ໬Ꮫ≀㉁࡞࡝࡛ởᰁࡉࢀ࡚࠸࡞࠸ࡇ࡜ࠊỈࡀΎ⃈࡛࠶ᐃࡍࡿ᪂ᡭἲࢆᵓ⠏ࡋࠊ⏕㣗㣗≀ࡿࡇ࡜ࠊỈ⏘㈨※ࡀ㇏ᐩ࡞ࡇ࡜࡞࡝ࡀ೺඲ᛶࡢせ⣲࡜ࡋ࡚㐃㙐࠾ࡼࡧᚤ⏕≀㣗≀㐃㙐ࢆ௓ࡋ࡚ື≀ࣉࣛࣥࢡࢺࣥ࡟

ᣲࡆࡽࢀࡿࡀࠊ࠸ࡎࢀࡶே㛫♫఍࡟࠾ࡅࡿ⏝㏵ࢆ᝿ᐃࡋࡓ

⮳ࡿ᭷ᶵ≀㔞㸦ࢫࢺࢵࢡ࣭ࣇ࣮ࣟ㸧ࢆᢕᥱࡍࡿࠋࡲࡓࠊ᭷

ࡶࡢ࡛࠶ࡾࠊ†἟ࡑࡢࡶࡢࡢ೺඲ᛶࢆホ౯ࡋࡓࡶࡢ࡜ࡣ࠸

ᶵ≀㔞ࢆᢕᥱࡍࡿୖ࡛࣮࣋ࢫ࡜࡞ࡿ඲᭷ᶵⅣ⣲㸦72&㸧࠾࠼࡞࠸ࠋࡲࡓࠊ౛࠼ࡤỈ㉁࡜Ỉ⏘㈨※ࡣ㣗≀㐃㙐ࢆ㏻ࡌ࡚

ࡼࡧࡑࡢᵓᡂせ⣲࡛࠶ࡿ 32&࣭'2& ࡟ࡘ࠸࡚ࠊᡭἲ࡟ࡼࡿ

┦஫࡟㛵ಀࡋ࡚࠾ࡾࠊྠ᫬࡟ྥୖࡉࡏࡿࡇ࡜ࡀᅔ㞴࡞ሙྜᐃ್ࡢࡤࡽࡘࡁࡀ኱ࡁ࠸ࡇ࡜࠿ࡽࠊ㧗⢭ᗘ࡟ᐃࡍࡿᡭἲࡢ᳨ウࢆ⾜࠺ࠋࡶ࠶ࡿࠋỈᇦ⏕ែ⣔ࡢ೺඲ᛶࢆᐃ⩏ࡍࡿヨࡳࡣࡇࢀࡲ࡛ᩘከࡃ➨  ❶㸸≀㉁ᚠ⎔ࡢ≧ἣᢕᥱᡭἲ࡟㛵ࡍࡿ◊✲࡞ࡉࢀ࡚ࡁ࡚࠾ࡾࠊ&RVWDQ]D㸦㸧ࡣࡑࢀࡽࢆ௨ୗࡢ ᭷ᶵ≀ࡢⅣ⣲Ᏻᐃྠ఩యẚࡸศᏊࢧ࢖ࢬศᕸ➼ࠊⅣ⣲ࢆࡘ࡟⥲ᣓࡋࡓ㸹ձᜏᖖᛶࠊղ⑓Ẽࡢ࡞࠸ࡇ࡜ࠊճከᵝᛶ࣭୰ᚰ࡜ࡍࡿ≀㉁ᚠ⎔ࡢᢕᥱ࡟㐺ษ࡞ᣦᶆࢆ᳨ウࡍࡿࠋⅣ⣲」㞧ᛶࠊմᏳᐃᛶ࣭᚟ඖᛶࠊյᡂ㛗ຊࠊնせ⣲㛫ࡢࣂࣛࣥᏳᐃྠ఩యẚ࡟ࡘ࠸࡚ࡣࠊ➨ᅄᮇ୰ᮇィ⏬࡟࠾࠸࡚⏕ศゎࢫࠋࡇࢀࡽ඲࡚ࢆྠ᫬࡟ᢅ࠺ࡇ࡜ࡣᐜ࡛᫆ࡣ࡞࠸ࡓࡵࠊᮏ

୰ࡢྠ఩యẚࡢኚ໬ࢆㄪᰝࡋ࡚࠸ࡿࡇ࡜࠿ࡽࠊࡇࢀࡽࡢㄪ

◊✲࡛ࡣࡲࡎࠕ†἟ࡢ೺඲ᛶࠖࢆ⾲ࡍ㡯┠࡜ࡋ࡚ࠕ†἟ෆᰝࢆ⥅⥆ࡋࡘࡘࠊ᭷ᶵ≀ࣇ࣮ࣟࡢᢕᥱ➼࡟ᛂ⏝࡛ࡁࡿᡭἲ

࡛ࡢ≀㉁ᚠ⎔ࡀ෇⁥࡛࠶ࡿࡇ࡜ࠖ࡟╔┠ࡍࡿࠋࡑࡢ⤖ᯝ࡜ࢆ᳨ウࡍࡿࠋศᏊࢧ࢖ࢬ࡟ࡘ࠸࡚ࡣࠊ'2& ࡢศᏊࢧ࢖ࢬู

ࡋ࡚Ỉ㉁ࡸỈ⏘㈨※࡟㛵ࡍࡿ┠ᶆࡶ୍ᐃ㐩ᡂࡉࢀࡿ࡜ࡢ

ࡢศゎ㏿ᗘࢆㄪ࡭ࠊ⏕ศゎᛶᣦᶆ࡜ࡋ࡚ࡢྍ⬟ᛶࢆ᳨ウࡍ௬ㄝࢆ❧࡚ࡿࠋࡇࢀࡣࠊ㣧ᩱỈ➼࡜ࡋ࡚ࡢỈ㉁࡜㨶௓㢮㈨ࡿࠋ※ࡢ㇏࠿ࡉࡢ୧❧ࢆồࡵࡽࢀࡿ†἟࡛≉࡟᭷⏝࡜࡞ࡿࠋ

ᮏ◊✲࡛ࡣࠊ†἟ෆࡢ⏕≀㛫ࡢ≀㉁ࣇ࣮ࣟ࡟╔┠ࡋࠊ† ≀㉁ᚠ⎔ホ౯ᡭἲࡢᵓ⠏ ࡣࡌࡵ࡟

἟඲య࡛ࡳࡓ࡜ࡁࡢ≀㉁ᚠ⎔ࡢ෇⁥ࡉࢆ⾲ࡍᣦᶆࢆᥦ᱌
ࡍࡿࠋḟ࡟ࠊ⍇⍈†࡜ࡑࡢὶᇦ࡟࠾ࡅࡿ≀㉁ᚠ⎔ࢆ෌⌧࡛ࠕ†἟ࡀ೺඲࡛࠶ࡿࠖ࡜ࡣ࡝ࡢࡼ࠺࡞≧ែࢆᣦࡍࡔࢁ࠺

ࡁࡿᩘ⌮ࣔࢹࣝࢆᵓ⠏ࡋࠊࡑࢀࡽᣦᶆࡢ⌧≧ࡸᣦᶆ㛫ࡢ㛵ᅗ  ᮏ◊✲ࡢ඲యീ࡜ྛ❶ࡢ㛵ಀ

56⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ヨ㦂◊✲ሗ࿌᭩➨ 16 ྕಀࢆゎᯒࡍࡿࡇ࡜࡛ࠊୖグࡢ௬ㄝࢆ᳨ドࡍࡿࠋᩘ⌮ࣔࢹࣝホ౯ᑐ㇟ࡢ†἟࡟࠾ࡅࡿ⏕ែ⣔඲యࢆࡳ࡚ࠊศゎࡉࢀࡎ࡜ࡋ࡚ࡣࠊࣔࢹࣝᵓ㐀࡟ࡼࡗ࡚ホ౯࡛ࡁࡿᅉᏊࡢ㐪࠸ࡸᢅ࡟ṧࡉࢀࡿ᭷ᶵ≀ࡀ࡯࡜ࢇ࡝Ꮡᅾࡏࡎࠊ⏕⏘࠿ࡽ࿧྾ࢆᘬ

࠸ࡸࡍࡉ࡜࠸ࡗࡓ≉ᚩࢆ⪃៖ࡋࡓୖ࡛ࠊձ†ෆ࡟࠾ࡅࡿ㣗࠸ࡓࡶࡢࡀ⏕ែ⣔ෆࡢ⏕య㔞ࡢ⵳✚࡟ᑐᛂࡋ࡚࠸ࡿࠋ

≀㐃㙐ࡢ≧ἣࢆ⡆᫆࡟ィ⟬ࡍࡿࠕ㣗≀㐃㙐ࣔࢹࣝࠖࠊղ⍇ղࠕ⁫ࡾࡀ࡞࠸ࠖ㸸㌿᥮ຠ⋡㸦㸻஧ḟ⏕⏘㔞㸭୍ḟ⏕⏘㔞⍈†ὶᇦ㸦㝣ᇦ࣭†ෆ㸧࡟࠾ࡅࡿỈ࣭≀㉁ᚠ⎔ࡢศᕸ࠾ࡼ

➼㸧ࡧ୕ḟඖⓗ࡞≧ἣࢆィ⟬ࡍࡿࠕ⍇⍈†ὶᇦỈ≀㉁ᚠ⎔ࣔࢹḟࡢᾘ㈝⪅࡟ከࡃཷࡅΏࡉࢀࠊ⏕≀ࡢ㐃㙐ࡢ୰࡛ຠ⋡ࡼࡃࣝࠖࡢ  ✀㢮ࢆᵓ⠏ࡋࠊྛ✀ᣦᶆ್ࢆホ౯ࡍࡿࠋ

฼⏝ࡉࢀ࡚࠸ࡿࠋ

 ᪉ἲ
 ≀㉁ᚠ⎔ࡢ෇⁥ࡉࢆ⾲ࡍᣦᶆࡉࡽ࡟ࠊỈ㉁࡜㨶௓㢮㈨※ࡢࣂࣛࣥࢫࢆᤊ࠼ࡿ௨ୗࡢᣦ
ᶆࢆ㏣ຍࡋࠊ†἟ࡢ೺඲ᛶࢆホ౯ࡍࡿࠋ

ࠕே㛫ࡢ೺ᗣࠖࢆホ౯ᑐ㇟࡜ࡋࡓሙྜࠊࡑࢀࡀయ㔜ࡔࡅ࡛ྛᰤ㣴ẁ㝵ࢆࡳ࡚ࠊ᳜≀࡟ࡼࡗ࡚⏕⏘ࡉࢀࡓ᭷ᶵ≀ࡀ㧗ࢀࡿ࡜⪃࠼ࡿேࡣ࠸࡞࠸ࡔࢁ࠺ࠋࣂࣛࣥࢫࡢྲྀࢀࡓ㣗ճࠕ೫ࡾࡀ࡞࠸ࠖ㸸⏕≀ࣂࣛࣥࢫ㸦㸻㨶㢮ࣂ࢖࣐࢜ࢫ㸭᳜≀ࣉࣛࣥࢡࢺࣥࣂ࢖࣐࢜ࢫ㸧஦ࢆ㐺㔞ᦤࡾࠊ᪥ࠎࡢ⏕άࡸ㐠ືࡢ୰࡛㐺ษ࡟ᾘ໬࣭ศゎ≀㉁ᚠ⎔ࡀ෇⁥࡟࡞ࡗࡓ⤖ᯝ࡜ࡋ࡚ࠊỈ㉁ࡀ୍ᐃࣞ࣋ࣝ

ࡉࢀࠊ࿧྾ࡸ᤼ἥ➼࡟ࡼࡾ᤼ฟࡉࢀࡿࠋ⤖ᯝ࡜ࡋ࡚ࠊయ㔜࡟ᢚ࠼ࡽࢀࠊ࠿ࡘ㨶௓㢮ࡢ㈨※㔞ࡀಖ඲ࡉࢀࡿ࡜࠸࠺ࡼ࠺

ࡀᴫࡡ⥔ᣢࡉࢀࡿ࡜࡜ࡶ࡟ࠊ኱ࡁ࡞⑓Ẽࡶ࡞ࡃᬽࡽࡍࡇ࡜

࡟ࠊྛᰤ㣴ẁ㝵ࡢࣂ࢖࣐࢜ࢫࡀࠕ೫ࡾ࡞ࡃࠖᏑᅾࡍࡿࠋ

ࡀ࡛ࡁࡿࠋయ㔜ࡢࡼ࠺࡞ࠕࢫࢺࢵࢡࠖࡔࡅ࡛ࡣ࡞ࡃࠊᦤྲྀ
㔞ࠊ࿧྾㔞ࠊ᤼ἥ㔞࡜࠸ࡗࡓࠕࣇ࣮ࣟࠖࢆࡳࡿࡇ࡜࡛ึࡵ

 㣗≀㐃㙐ࣔࢹࣝࡢᴫせ࡚ே㛫ࡢ೺ᗣ࡞ጼࡀᾋ࠿ࡧୖࡀࡿࠋࡑ࠺ࡋࡓ⪃࠼᪉ࡀࠊ†⍇⍈†ࡢ⏕ែ⣔ᵓ㐀ࢆ⡆᫆࡟⾲⌧ྍ⬟࡞㣗≀㐃㙐ࣔࢹ἟ࡢ⏕ែ⣔࡟ࡶᙜ࡚ࡣࡲࡿ࡜⪃࠼ࡿ㸦బ⸨ࡽࠊD㸧ࠋࣝࢆᵓ⠏ࡋࡓࠋලయⓗ࡟ࡣࠊ⍇⍈†඲యࢆ  ࣎ࢵࢡࢫࡢ᏶

⏕ែ⣔ࢆࠊ⏕⏘⪅ࠊᾘ㈝⪅ࠊศゎ⪅ࡢ㣗≀㐃㙐㛵ಀ࠿ࡽ඲ΰྜᵴ࡜௬ᐃࡋࠊᅗ  ࡟♧ࡍ⏕≀✀ࡢ⏕⏘ࡸᤕ㣗ࠊ࿧ᶍᘧⓗ࡟⾲⌧ࡋࡓࡶࡢࢆᅗ  ࡟♧ࡍࠋ⏕⏘⪅ࡢගྜᡂ࡟

྾ࠊศゎࠊỿ㝆➼ࢆ⾲⌧ࡍࡿࣔࢹࣝ࡜ࡋࡓ㸦బ⸨ࡽࠊE㸹

ࡼࡾ⏕⏘ࡉࢀࡓ᭷ᶵ≀ࡣࠊ୍᪦ࡣ⮬㌟ࡢࣂ࢖࣐࢜ࢫࡢቑຍ

బ⸨ࡽࠊF㸧ࠋᏘ⠇ኚ໬ࡣ⪃៖ࡏࡎࠊ ᖺ௦࡟࠾ࡅࡿ

࡜࡞ࡿࡀࠊྠ᫬୪⾜ⓗ࡟࿧྾ࡸ⿕㣗ࠊศゎ࡟ࡼࡗ࡚ᾘ㈝ࡉ

ᖺ㛫ࡢᖹᆒⓗ࡞≧ἣࢆ෌⌧࡛ࡁࡿࡼ࠺࡟ࡋࡓࠋὶධ㈇Ⲵ࠾

ࢀࠊ࠸ࡎࢀ࡟ࡶᅇࡽ࡞࠸ࡶࡢࡀ㞴ศゎ≀࡜ࡋ࡚⣔ෆ࡟⵳✚ࡼࡧᰤ㣴ሷ࡜ࡋ࡚ࡣࠊ⏕≀࡟฼⏝ࡉࢀࡸࡍ࠸⁐Ꮡែࣜࣥ

ࡍࡿࠋᾘ㈝⪅ࡸศゎ⪅ࡶྠᵝ࡟ࠊᦤྲྀࡋࡓ᭷ᶵ≀ࡣࡑࡢࣂ㸦'3㸧ࡢࡳࢆ⪃៖ࡋࡓࠋ

࢖࣐࢜ࢫࡢቑຍࡸ࿧྾ࠊ㞴ศゎ≀࡜࡞ࡿࠋࡘࡲࡾ⏕ែ⣔඲

ὶධ㈇Ⲵ

య࡜ࡋ࡚ࡳࢀࡤࠊ୍ḟ⏕⏘ࡉࢀࡓ᭷ᶵ≀ࡣࠊྛࣂ࢖࣐࢜ࢫ

ศゎࡀᖹ⾮≧ែ࡟࠶ࡿ࡜௬ᐃࡍࢀࡤࠊ᭱⤊ⓗ࡟࿧྾࡟ࡼࡾᾘ㈝Nࡉࢀࡿ࠿ࠊ㞴ศゎ≀࡜ࡋ࡚⵳✚ࡍࡿ࠿ࡢ࡝ࡕࡽ࠿࡜࡞ࡿࠋ

ὶฟ

P

ᦤྲྀ

ᤕ㣗

Z

F

F

ỿ㝆



ࡋࡓࡀࡗ࡚ࠊ⏕⏘ࡉࢀࡓ᭷ᶵ≀ࡀ࡛ࡁࡿࡔࡅ↓㥏࡞ࡃά⏝ࡉࢀࠊୖ఩ࡢᾘ㈝⪅➼࡟ࡶᅇࡗ࡚࠸ࡃࡇ࡜ࠊࡍ࡞ࢃࡕࠕࣇᅗ  㣗≀㐃㙐ࣔࢹࣝࡢᵓ㐀㸹1 ࡣᰤ㣴ሷࠊ3 ࡣ᳜≀ࣉ࣮ࣟࠖ࡜ࡋ࡚ࡢ≀㉁ᚠ⎔ࡀ෇⁥࡛࠶ࡿࡇ࡜ࡀࠊ†἟ࡢ೺඲ࣛࣥࢡࢺࣥࠊ= ࡣື≀ࣉࣛࣥࢡࢺࣥࠊ) ࡣ㨶㢮㸦ࣉࣛࣥࢡᛶ࡟┤⤖ࡍࡿ࡜⪃࠼ࡽࢀࡿࠋ

ࢺࣥ㣗ᛶ㨶ࠊ㨶㣗ᛶ㨶㸧ࢆ♧ࡍࠋਫ਼ସ‫ܧ‬ʤໝࣞਦʥ


ೋ෾մ෼
ਫ਼ࢊं
ώ΢ΨϜη

ೋ෾մ෼

Ҳ࣏ਫ਼ࢊ

ྛࣔࢹࣝࣃ࣓࣮ࣛࢱࡣࠊ᭱኱್࠾ࡼࡧ᭱ᑠ್ࢆᩥ⊩➼࠿

ভඇं
ώ΢ΨϜη

අৱ

ࡽタᐃࡋࠊࡑࡢᖜࡢ⠊ᅖෆ࡛ࣛࣥࢲ࣒࡟್ࢆタᐃࡋ࡚ࣔࢹࣝࢆ  ᖺ㛫 5XQ ࡋࠊ ᖺ┠ࡢᰤ㣴ሷ⃰ᗘ࠾ࡼࡧྛࣂ࢖࢜

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ώ΢ΨϜη

෾մ

್ࡢ⠊ᅖෆ࡟࠶ࡾࠊ࠿ࡘኚືಀᩘࡀ୍

ᐃ್௨ୗ࡛࠶ࢀࡤࠊࡑࡢࣔࢹࣝࢆ᥇⏝ࡍࡿࡇ࡜࡜ࡋࡓࠋࣔ

‫ٷݼ‬
‫ٷݼ‬

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ᅗ  ⏕ែ⣔࡟࠾ࡅࡿ㣗≀㐃㙐ࡢᶍᘧᅗ

ࣥࢸ࢝ࣝࣟࢩ࣑࣮ࣗࣞࢩࣙࣥ࡟ࡼࡾࠊ ࣃࢱ࣮ࣥࡢࣔࢹ
ࣝࡀ᥇⏝ࡉࢀࡿࡲ࡛ィ⟬ࢆ⧞ࡾ㏉ࡋࡓ㸦ᅗ 㸧ࠋᚓࡽࢀࡓ  ࣃࢱ࣮ࣥࡢ⤖ᯝࢆࡶ࡜࡟ࠊ⏕ែ⣔ࡢࢫࢺࢵ௨ୖࡢ⪃ᐹ࠿ࡽࠊ†἟࡟࠾ࡅࡿ≀㉁ᚠ⎔ࡢ෇⁥ࡉࢆࠊ௨ࢡࡸࣇ࣮ࣟ㛫ࡢ㛵ಀࠊ࠾ࡼࡧ≀㉁ᚠ⎔ࡢ෇⁥ࡉᣦᶆ㛫ࡢ㛵ୗࡢ  ࡘࡢᣦᶆ࡛ᤊ࠼ࡿࠋ

ಀࢆゎᯒࡋࡓࠋᮏ◊✲࡛ࡣࠊ⍇⍈†࡟࠾ࡅࡿ୺ࡓࡿ⁺⋓ᑐձࠕ㐣୙㊊ࡀ࡞࠸ࠖ
㸸࿧྾ຠ⋡㸦㸻⩌㞟⥲࿧྾㔞㸭୍ḟ⏕㇟㨶ࡀ࢔ࣘ࡞࡝ࡢࣉࣛࣥࢡࢺࣥ㣗ᛶ㨶࡛࠶ࡿࡇ࡜ࢆ㋃ࡲ⏘㔞➼㸧࠼ࠊ⏕≀ࣂࣛࣥࢫᣦᶆ࡛⏝࠸ࡿ㨶㢮ࢆࣉࣛࣥࢡࢺࣥ㣗ᛶ㨶

⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮◊✲ሗ࿌᭩➨ 16 ྕ

57࡜ࡋࡓࠋ

㝣ᇦỈ≀㉁ᚠ⎔ࣔࢹࣝࡣࠊ⵨Ⓨᩓࣔࢹࣝࠊᆅ⾲ὶࣔࢹࣝࠊ
ᆅୗỈࣔࢹࣝ࡞࡝  ࡘࡢせ⣲ࣔࢹࣝ࠿ࡽᡂࡿศᕸᆺ≀⌮ࣔࢹࣝ㸦P ࣓ࢵࢩࣗ㸧࡛࠶ࡿࠋ†ෆὶືࣔࢹࣝࡣࠊ†ෆࡢỈࡸὶືࢆィ⟬ࡍࡿ‽  ḟඖࣔࢹࣝ㸦NP ࣓ࢵࢩࣗ ᒙ㸧࡛࠶ࡿࠋ†ෆ⏕ែ⣔ࣔࢹࣝࡣࠊ≀㉁ࡢ⛣ὶ࣭ᣑᩓ࣭ỿ
㝆㐣⛬ࠊỈ㸫ᗏ㉁┦஫స⏝ࢆྵࡴ†ෆࡢ⏕໬Ꮫ཯ᛂ㐣⛬ࢆ
グ㏙ࡋࡓ⏕ែ⣔ࣔࢹࣝ㸦†ෆὶືࣔࢹࣝ࡜ྠࡌ✵㛫ศ๭㸧࡛࠶ࡿࠋ෌⌧ᮇ㛫ࡣ 㹼 ᖺᗘࡢ  ࣨᖺ࡜ࡋࠊྛࣔࢹࣝ࡟
ࡘ࠸࡚ᩘࣨ᭶⛬ᗘࡢຓ㉮ᮇ㛫ࢆタᐃࡋࡓࠋᚋ㏙ࡍࡿࠊྠᮇ
㛫ࢆ୰ᚰ࡟ほࡉࢀࡓྛ≀㉁࣭ࣂ࢖࣐࢜ࢫࡢ⃰ᗘࡸ⏕⏘㔞➼࡜ࠊࣔࢹࣝ࡟ࡼࡿィ⟬⤖ᯝࢆẚ㍑ࡋ᳨࡚ドࢆ⾜࠺࡜࡜ࡶᅗ  ࣔࣥࢸ࢝ࣝࣟἲࢆ⏝࠸ࡓィ⟬ࣇ࣮ࣟ ⍇⍈†ὶᇦỈ≀㉁ᚠ⎔ࣔࢹࣝࡢᴫせ࡟ࠊ≀㉁ᚠ⎔ࡢ෇⁥ࡉᣦᶆࡢ᥎⛣࡟ࡘ࠸࡚ゎᯒࢆ⾜ࡗࡓࠋ ⤖ᯝ 㣗≀㐃㙐ࣔࢹࣝࡢ⤖ᯝ➹⪅ࡽࡀᵓ⠏ࡋࡓࠕ⍇⍈†ὶᇦỈ≀㉁ᚠ⎔ࣔࢹࣝࠖ㸦బࣂ࢖࣐࢜ࢫ࡜ࣂ࢖࣐࢜ࢫࡢ㛵ಀ࡟ࡘ࠸࡚ࡣࠊ᳜≀ࣉࣛࣥ⸨ࡽࠊ㸧ࢆᨵⰋࡋࠊ⍇⍈†࡜ࡑࡢὶᇦ࡟࠾ࡅࡿ≀㉁ᚠ

ࢡࢺࣥ࡜ື≀ࣉࣛࣥࢡࢺࣥࠊື≀ࣉࣛࣥࢡࢺࣥ࡜ࣉࣛࣥࢡ

⎔ࢆ෌⌧ࠊண

ࢺࣥ㣗ᛶ㨶ࠊ᳜≀ࣉࣛࣥࢡࢺࣥ࡜ࣉࣛࣥࢡࢺࣥ㣗ᛶ㨶ࡢ࠸࡛ࡁࡿࣔࢹࣝ࡜ࡋࡓࠋ

ᮏࣔࢹࣝࡣࠕ㝣ᇦỈ≀㉁ᚠ⎔ࣔࢹࣝࠖࠕ†ෆὶືࣔࢹࣝࠖ

ࡎࢀ࡟ࡘ࠸࡚ࡶ᭷ព࡞┦㛵ࡣ࡞࠿ࡗࡓ㸦S!㸧ࠋ'3 ⃰ᗘࠕ†ෆ⏕ែ⣔ࣔࢹࣝࠖࡢ  ࡘ࠿ࡽᡂࡾࠊࡑࢀࡒࢀẼ㇟ࡸᆅ࡜᳜≀ࣉࣛࣥࢡࢺࣥ࡟ࡘ࠸࡚ࡣࠊỴᐃಀᩘ  ࡜࠸࠺㠀ᙧࠊ♫఍᮲௳➼ࡢࢹ࣮ࢱ࡜௚ࡢࣔࢹࣝ࠿ࡽࡢฟຊࢆㄞࡳ㎸ᖖ࡟ప࠸┦㛵࡛ࡣ࠶ࡗࡓࡀ᭷ព࡞㛵ಀࡀᚓࡽࢀࡓࠋ

ࢇ࡛ࢩ࣑࣮ࣗࣞࢺࡍࡿ㸦ᅗ 㸧ࠋᰤ㣴ሷࡢ௚ࠊ᭷ᶵ≀࡜ࡋ୍᪉࡛ࠊ୍ḟ⏕⏘㔞࡜᳜≀ࣉࣛࣥࢡࢺࣥࠊື≀ࣉࣛࣥࢡ࡚ 72&㸦32& ࠾ࡼࡧ '2&㸧࡜ࡑࡢศゎᛶࢆ⪃៖࡛ࡁࠊࡲࡓ

ࢺࣥࡢྛࣂ࢖࣐࢜ࢫ࡜ࡢ㛵ಀࡣࠊ᭷ព࡞ṇࡢ┦㛵ࡀᚓࡽࢀ᳜≀ࣉࣛࣥࢡࢺࣥࢆ  ✀ࠊ㨶㢮ࢆ㣗ᛶࢆ⪃៖ࡋ  ✀࡟ศ㢮ࡓ㸦࠸ࡎࢀࡶ S㸧ࠋ㨶㢮ࣂ࢖࣐࢜ࢫ࡟ࡘ࠸࡚ࡣ᭷ព࡞

ࡋ࡚ィ⟬ࡀ࡛ࡁࡿࡼ࠺࡟ᨵⰋࡋࡓࠋ

┦㛵ࡣ࡞࠿ࡗࡓ㸦ᅗ 㸧ࠋᅗ  ⍇⍈†ὶᇦỈ≀㉁ᚠ⎔ࣔࢹࣝࡢᴫせ

58⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ヨ㦂◊✲ሗ࿌᭩➨ 16 ྕ≀㉁ᚠ⎔ࡢ෇⁥ࡉᣦᶆ࡟╔┠ࡍࡿ࡜ࠊ᳜≀ࣉࣛࣥࢡࢺࣥ

72& ࡀୖ᪼ࡋ 71 ࡀῶᑡࡍࡿഴྥ࡞࡝ࢆⰋዲ࡟෌⌧ࡍࡿࡇ࠿ࡽື≀ࣉࣛࣥࢡࢺࣥࠊ࠾ࡼࡧື≀ࣉࣛࣥࢡࢺࣥ࠿ࡽࣉࣛ

࡜ࡀ࡛ࡁࡓ୍᪉࡛ࠊ᫓ࡢ᳜≀ࣉࣛࣥࢡࢺࣥࡢࣈ࣮࣒ࣝࡸ୍

ࣥࢡࢺࣥ㣗ᛶ㨶࡬ࡢ㌿᥮ຠ⋡ࡢ཮᪉ࡀࠊ⏕≀ࣂࣛࣥࢫ࡜ṇ᫬ⓗ࡞ 73 ⃰ᗘࡢୖ᪼࡞࡝ࡣ෌⌧࡛ࡁ࡞࠿ࡗࡓࠋ

ࡢ᭷ព࡞┦㛵ࡀࡳࡽࢀࡓ㸦ᅗ 㸧
ࠋ





0.1
0

䝥䝷㣗㨶䝞䜲䜸䝬䝇䠄gC/m3䠅

00.1

p=0.15

0.02

0.01

0

2
1

R² = 0.1074
0

0.05

ほ ᆅⅬ

0

0.05
0.1
0.15
୍ḟ⏕⏘㔞䠄gC/m3/day䠅

0.03

0

0.15

18A
18B
18C
17A
17B
17C
17C'
16A
16B
16C
15A
15B
15C
14A
14B
14C
13A
13B
13C
12A
12B
12C
11A
11B
11C
10A
10B
10C
9A
9B
8A
8B
8C
7A
7B
7C
6A
6B
6C
5A
5B
5C
4A'
4A
4B
3

0.2

ほ ್
ィ⟬್

0

0.05
0.1
0.15
୍ḟ⏕⏘㔞䠄gC/m3/day䠅

0.6
0.5

0.03
p=0.83

0.02

0.4
0.3
0.2
0.1

0.01

0
18A
18B
18C
17A
17B
17C
17C'
16A
16B
16C
15A
15B
15C
14A
14B
14C
13A
13B
13C
12A
12B
12C
11A
11B
11C
10A
10B
10C
9A
9B
8A
8B
8C
7A
7B
7C
6A
6B
6C
5A
5B
5C
4A'
4A
4B
3

0.3

p=0.001<0.01**
TOC䠄mg/L䠅

R² = 0.6106

༡†

໭†

3

TN䠄mg/L䠅

0.4

0.2

ほ

0
0

0.05
0.1
0.15
୍ḟ⏕⏘㔞䠄gC/m3/day䠅

0.05
0.1
0.15
୍ḟ⏕⏘㔞䠄gC/m3/day䠅

ᆅⅬ

0.05



ᅗ  ୍ḟ⏕⏘㔞࡜⏕≀ࣂ࢖࣐࢜ࢫࡢ㛵ಀ

0.04
TP䠄mg/L䠅

p=0.000<0.01**ື䝥䝷䝞䜲䜸䝬䝇䠄gC/m3䠅

0.5

㨶㣗㨶䝞䜲䜸䝬䝇䠄gC/m3䠅᳜䝥䝷䝞䜲䜸䝬䝇䠄gC/m3䠅

4

0.03
0.02
0.01

0.2



ほ ᆅⅬ

ᅗ  †ෆỈ㉁ࡢ෌⌧ィ⟬⤖ᯝ㸦 ᖺᗘᖹᆒ㸧

R² = 0.1349

0.1


TOC䠖17B䠄௒ὠἈ୰ኸ䠅

0

0.1

0.2

0.3

0.4

᳜≀䝥䝷䞁䜽䝖䞁→ື≀䝥䝷䞁䜽䝖䞁㌿᥮ຠ⋡⃰ᗘ䠄mg/L䠅

p=0.000<0.01**

0

ィ⟬್

2
1

0.2

TN䠖17B䠄௒ὠἈ୰ኸ䠅R² = 0.2564

Mar-19Jan-19Feb-19Dec-180.1

Mar-19Feb-19Jan-19Dec-18

Nov-18Oct-18

Sep-18Aug-18

Jul-18Jun-18May-18Apr-18Mar-18

Feb-18Jan-18Dec-17Oct-17

Sep-17

Nov-17

ほ ್

ィ⟬್

0.02
0.015

⃰ᗘ䠄mg/L䠅F㸧Aug-17

TP䠖17B䠄௒ὠἈ୰ኸ䠅ື≀䝥䝷䞁䜽䝖䞁→䝥䝷䞁䜽䝖䞁㣗㨶㌿᥮ຠ⋡ᅗ  ㌿᥮ຠ⋡࡜⏕≀ࣂࣛࣥࢫࡢ㛵ಀ㸦బ⸨ࡽࠊ

Jul-17

Apr-170.3

Jun-170
May-170.2

Oct-18

0.2

0.01

0.005

ࡍࡿࡇ࡜ࡀ࡛ࡁࡓ㸦ᅗ 㸧ࠋᏘ⠇ኚືࡢ౛࡜ࡋ࡚௒ὠἈ
୰ኸ㸦%㸧࡟࠾ࡅࡿ෌⌧⤖ᯝࢆᅗ  ࡟♧ࡍࡀࠊኟᏘ࡟

Mar-19Feb-19Jan-19Dec-18

Nov-18

Sep-18Aug-18

Jul-18Jun-18May-18Apr-18Mar-18

Feb-18Jan-18Dec-17

Nov-17Oct-17

Sep-17Aug-17

Apr-17†ෆ⾲ᒙࡢ 72&ࠊ71ࠊ73 ⃰ᗘࡢศᕸ࡟ࡘ࠸࡚ࡣᴫࡡ෌⌧Jul-170 ⍇⍈†ὶᇦỈ≀㉁ᚠ⎔ࣔࢹࣝࡢ⤖ᯝ

Jun-17



May-17

0.1

ィ⟬್

0.3

p=0.000<0.01**
0

ほ ್

0.4

0.1

0

Nov-18

Sep-18

Jul-18Aug-18Jun-18Apr-18May-18Mar-18Jan-18

Feb-18Dec-17Oct-17

Nov-17

Sep-17

Jul-17Aug-17

Jun-17

Apr-17May-170⃰ᗘ䠄mg/L䠅⏕≀䝞䝷䞁䝇

ほ ್

3Oct-18⏕≀䝞䝷䞁䝇

18A
18B
18C
17A
17B
17C
17C'
16A
16B
16C
15A
15B
15C
14A
14B
14C
13A
13B
13C
12A
12B
12C
11A
11B
11C
10A
10B
10C
9A
9B
8A
8B
8C
7A
7B
7C
6A
6B
6C
5A
5B
5C
4A'
4A
4B
3

0

ᅗ  Ỉ㉁Ꮨ⠇ኚືࡢ෌⌧ィ⟬⤖ᯝ ௒ὠἈ୰ኸ % ⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮◊✲ሗ࿌᭩➨ 16 ྕ59୍ḟ⏕⏘㔞ࡣගྜᡂ㸫ග᭤⥺ࢆ⏝࠸ࡓ㐃⥆ほࡢ⤖ᯝὶධ᭷ᶵⅣ⣲㔞䠄໭†䠅ࡀᚓࡽࢀࡓࡀࠊ ᖺᗘࡣほ್ࡢ᪉ࡀ  ಸ⛬ᗘ኱ࡁ࠸್࡜࡞ࡗࡓࠋ ᖺᗘࡣኟᏘ࠾ࡼࡧ⛅Ꮨ࡟኱ᆺ⥳⸴ࡀከࡃቑṪࡋࡓࡀࠊࡑࡢഴྥࢆࣔࢹ࡛ࣝ෌⌧࡛ࡁ࡞࠿ࡗࡓࡇ࡜

Ⅳ⣲䝣䝻䞊䠄tC/month䠅ẚ㍑ࢆ⾜ࡗࡓࠋ ᖺᗘࡣ㔞࣭ኚື࡜ࡶ࡟༑ศ࡞෌⌧ᛶ⩌㞟⥲࿧྾㔞䠄໭†䠅

30,00025,00020,00015,00010,0005,000࡟㉳ᅉࡍࡿ࡜⪃࠼ࡽࢀࡓ㸦బ⸨ࡽࠊF㸧
ࠋ

Apr-17May-17
Jun-17
Jul-17Aug-17
Sep-17Oct-17
Nov-17
Dec-17Jan-18
Feb-18Mar-18Apr-18May-18Jun-18
Jul-18Aug-18
Sep-18Oct-18
Nov-18Dec-18Jan-19Feb-19Mar-190ࣔࢹࣝ࠿ࡽィ⟬ࡉࢀࡓࠊ໭†࡟࠾ࡅࡿⅣ⣲ࣇ࣮ࣟ㸦୍ḟ⏕⏘㔞ࠊ⩌㞟⥲࿧྾㔞ࠊὶධ᭷ᶵⅣ⣲㔞㸧ࠊ࠾ࡼࡧ࿧྾ຠ

160%⋡㸦ࡇࡇ࡛ࡣศẕࡢ୍ḟ⏕⏘㔞ࡢ௚࡟ὶධ᭷ᶵⅣ⣲㔞ࡶ⪃140%៖㸧ࢆᅗ  ࡟♧ࡍࠋ࿧྾ຠ⋡ࡣ୍᫬ᮇࢆ㝖ࡁᴫࡡ୍ᐃ࡛
໭†࡟࠾ࡅࡿ୍ḟ⏕⏘㔞ࠊ஧ḟ⏕⏘㔞㸦ື≀ࣉࣛࣥࢡࢺ

120%
࿧྾ຠ⋡

࠶ࡾࠊ ᖺ㛫ࡢᖹᆒ್ࡣ 㸣࡛࠶ࡗࡓࠋ

100%
80%
60%
Apr-17May-17
Jun-17
Jul-17Aug-17
Sep-17Oct-17
Nov-17
Dec-17Jan-18
Feb-18Mar-18Apr-18May-18Jun-18
Jul-18Aug-18
Sep-18Oct-18
Nov-18Dec-18Jan-19Feb-19Mar-19ࣥࡢ⏕⏘㔞㸦ྠ໬ศ㸧㸧ࠊ୕ḟ⏕⏘㔞㸦ࣉࣛࣥࢡࢺࣥ㣗ᛶ㨶ࡢ⏕⏘㔞㸦ྠ໬ศ㸧㸧ࠊ࠾ࡼࡧ୍ḟ㌿᥮ຠ⋡㸦㸻஧ḟ⏕⏘㔞㸭୍ḟ⏕⏘㔞㸧ࠊ஧ḟ㌿᥮ຠ⋡㸦㸻୕ḟ⏕⏘㔞㸭஧ḟ⏕⏘㔞㸧ࢆᅗ  ࡟♧ࡍࠋ⏕⏘㔞ࡣ࠸ࡎࢀࡶኟᏘ࡟㧗ࡃࠊ⛅୍ḟ⏕⏘㔞䠄໭†䠅
35,000ࢺࣥ࡟ẚࡋ࡚ື≀ࣉࣛࣥࢡࢺࣥࡢ⏕⏘㔞ࡀᑠࡉ࠸࡜⪃࠼

30,000⏕⏘㔞䠄tC/month䠅ࡘ࠸࡚ࡶྠᵝࡢഴྥࡀࡳࡽࢀࡓࡓࡵࠊ෤Ꮨࡣ᳜≀ࣉࣛࣥࢡࡽࢀࡓࠋ ⪃ᐹ

15,00010,0005,000
0Apr-17May-17
Jun-17
Jul-17Aug-17
Sep-17Oct-17
Nov-17
Dec-17Jan-18
Feb-18Mar-18Apr-18May-18Jun-18
Jul-18Aug-18
Sep-18Oct-18
Nov-18Dec-18Jan-19Feb-19Mar-19࠺㛵ಀ㸦㏫࡟ゝ࠼ࡤࠊࠕỈΎࡅࢀࡤ㨶᳇ࡲࡎࠖ࡜࠸࠺㛵ಀ㸧୍ḟ㌿᥮ຠ⋡䠄໭†䠅ࡣ᫂ࡽ࠿࡛ࡣ࡞࠿ࡗࡓࠋ୍᪉࡛ࠊ୍ḟ⏕⏘㔞ࡀ㧗ࡅࢀࡤ᳜㌿᥮ຠ⋡䠄䠂䠅

30%

20%

10%

ࡲࡓ㌿᥮ຠ⋡࡜⏕≀ࣂࣛࣥࢫࡢ㛫࡟᭷ព࡞┦㛵ࡀࡳࡽࢀࡓࡇ࡜ࡣࠊື≀ࣉࣛࣥࢡࢺࣥࡸࣉࣛࣥࢡࢺࣥ㣗ᛶ㨶࡟㣗

Apr-17May-17
Jun-17
Jul-17Aug-17
Sep-17Oct-17
Nov-17
Dec-17Jan-18
Feb-18Mar-18Apr-18May-18Jun-18
Jul-18Aug-18
Sep-18Oct-18
Nov-18Dec-18Jan-19Feb-19Mar-190%࡭ࡽࢀࡸࡍ࠸㣵⏕≀ࡀᏑᅾࡍࡿࡇ࡜ࡀࠊࠕỈࡀࡁࢀ࠸࡛㨶ࡀ㇏࠿࡛࠶ࡿࠖ⎔ቃࡢࡓࡵ࡟㔜せ࡛࠶ࡿࡇ࡜ࢆ♧ࡋ࡚࠸ࡿࠋ
㏆ᖺ⍇⍈†࡛ࡣ᳜≀ࣉࣛࣥࢡࢺࣥ✀ࡢኚ㑄ࡀぢࡽࢀ࡚࠾ࡾࠊࡇࡢࡇ࡜ࡀ㣗≀㐃㙐ࢆ㏻ࡌ࡚Ỉ㉁ࡸ㨶㢮㈨※࡟ᙳ㡪ࢆ஧ḟ㌿᥮ຠ⋡䠄໭†䠅40%≀ࣉࣛࣥࢡࢺࣥࡸື≀ࣉࣛࣥࢡࢺࣥࣂ࢖࣐࢜ࢫࡣቑຍࡍ
ࡿୖ࡛㔜୕ḟ⏕⏘㔞䠄໭†䠅

20,000࠶ࡿ࠸ࡣ᳜≀ࣉࣛࣥࢡࢺࣥࡀከࡅࢀࡤ㨶ࡀከࡃ࡞ࡿ࡜࠸

せ࡞ᣦᶆ࡜࡞ࡿࡇ࡜ࡀ♧၀ࡉࢀࡓࠋ

஧ḟ⏕⏘㔞䠄໭†䠅

25,000㣗≀㐃㙐ࣔࢹࣝ࡟ࡼࡿゎᯒ⤖ᯝ࠿ࡽࡣࠊ'3 ⃰ᗘࡀ㧗࠸ࠊࡿഴྥࡀࡳࡽࢀࡓࠋ௨ୖࡼࡾࠊ᳜≀ࣉࣛࣥࢡࢺࣥࡢ㔞࡛ࡣᅗ  Ⅳ⣲ࣇ࣮ࣟ࡜࿧྾ຠ⋡㸦໭†඲య㸧Ꮨ࠿ࡽ෤Ꮨ࡟ῶᑡࡍࡿഴྥࡀࡳࡽࢀࡓࡀࠊ୍ḟ㌿᥮ຠ⋡࡟࡞ࡃ୍ḟ⏕⏘㔞ࢆࡳࡿࡇ࡜ࡀࠊ†἟ࡢ೺඲ᛶࢆ

୍ḟ⏕⏘㔞䠄໭†䠅

35,000㸦⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ࠊ㸧࡜ࣔࢹࣝィ⟬್ࡢᅗ  ⏕⏘㔞࡜㌿᥮ຠ⋡㸦໭†඲య㸧 ࡲ࡜ࡵ

୚࠼࡚࠸ࡿྍ⬟ᛶࡀ♧၀ࡉࢀࡓࠋ
⍇⍈†ὶᇦỈ≀㉁ᚠ⎔ࣔࢹࣝࢆ⏝࠸ࡿࡇ࡜࡛ࠊ࿧྾ຠ⋡ᮏ◊✲࡛ࡣࠊࠕ†἟ࡢ೺඲ᛶࠖࢆホ౯ࡍࡿୖ࡛ࠕ†἟ෆࡸ㌿᥮ຠ⋡࡜࠸ࡗࡓ≀㉁ᚠ⎔ࡢ෇⁥ࡉࢆ⾲ࡍᣦᶆࡢᏘ⠇࡛ࡢ≀㉁ᚠ⎔ࡀ෇⁥࡛࠶ࡿࡇ࡜ࠖ࡟╔┠ࡋࠊ≀㉁ᚠ⎔ࡢ෇ኚືࡸࡑࡢせᅉࢆヲ⣽࡟ゎᯒ࡛ࡁࡿࡇ࡜ࡀ᫂ࡽ࠿࡟࡞ࡗ

⁥ࡉࢆ⾲ࡍ௨ୗ  ࡘࡢᣦᶆࢆᥦ᱌ࡋࡓࠋࡍ࡞ࢃࡕࠊձࠕ㐣ࡓࠋ୍᪉࡛ྛ⏕≀✀ࡢࣂ࢖࣐࢜ࢫࡸ⏕⏘㔞ࡢᏘ⠇ኚື࡟ࡘ୙㊊ࡀ࡞࠸ࠖ
㸸࿧྾ຠ⋡㸦㸻⩌㞟⥲࿧྾㔞㸭୍ḟ⏕⏘㔞➼㸧ࠊ࠸࡚ࡣほղࠕ⁫ࡾࡀ࡞࠸ࠖ㸸㌿᥮ຠ⋡㸦㸻஧ḟ⏕⏘㔞㸭୍ḟ⏕⏘㔞ࢹ࣮ࢱࡢྲྀᚓࢆྵࡵࡉࡽ࡞ࡿ᳨ドࡀᚲせ࡜⪃࠼ࡽࢀࡓࠋ
➼㸧ࠊճࠕ೫ࡾࡀ࡞࠸ࠖ
㸸⏕≀ࣂࣛࣥࢫ㸦㸻㨶㢮ࣂ࢖࣐࢜ࢫ
㸭᳜≀ࣉࣛࣥࢡࢺࣥࣂ࢖࣐࢜ࢫ㸧࡛࠶ࡿࠋ
ḟ࡟ࠊ⍇⍈†࡜ࡑࡢὶᇦ࡟࠾ࡅࡿ≀㉁ᚠ⎔ࢆ෌⌧࡛ࡁࡿ

60⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ヨ㦂◊✲ሗ࿌᭩➨ 16 ྕ ✀㢮ࡢᩘ⌮ࣔࢹࣝࢆᵓ⠏ࡋࠊࡑࢀࡽᣦᶆࡢ⌧≧ࡸᣦᶆ㛫ࢆホ౯ࡍࡿࡓࡵࠊ኱ᆺ⸴㢮ࢆྵࡴ⏕⏘⪅ࢆ 3 ࡘࡢࢧ࢖ࢬ࡟

ࡢ㛵ಀࢆゎᯒࡋࡓࠋ㣗≀㐃㙐ࣔࢹࣝࢆ⏝࠸ࡓ⤖ᯝ࠿ࡽࡣࠊ

ศࡅ㸦<20 Pm, 20-45 Pm, 45-250 Pm㸧ࠊྛࢧ࢖ࢬࡢ⏕⏘⪅ࠊᰤ㣴ሷࡢ⃰ᗘࡸ᳜≀ࣉࣛࣥࢡࢺࣥ࡜㨶ࡢ㛵ಀࡣ᫂☜࡛ࡣື≀ࣉࣛࣥࢡࢺࣥࠊᅾ᮶㨶ࡢⅣ⣲࣭❅⣲Ᏻᐃྠ఩యࢆ 2 ᖺ࡞࠿ࡗࡓࠋ୍᪉࡛ࠊ㌿᥮ຠ⋡࡜⏕≀ࣂࣛࣥࢫࡢ㛫࡟᭷ព࡞௨ୖ࡟Ώࡗ࡚ศᯒࡋࡓ㸦ᅾ᮶㨶ࡢࡳྛᖺ 1 ᅇ㸧ࠋࡑࡢ⤖ᯝ┦㛵ࡀࡳࡽࢀࡓࡇ࡜࠿ࡽࠊື≀ࣉࣛࣥࢡࢺࣥࡸࣉࣛࣥࢡࢺ

ࢆ⏝࠸࡚ࠊྛࢧ࢖ࢬࡢ⏕⏘⪅࡜ື≀ࣉࣛࣥࢡࢺࣥ࡜ࡢ㛵ಀࣥ㣗ᛶ㨶࡟㣗࡭ࡽࢀࡸࡍ࠸㣵⏕≀ࡀᏑᅾࡍࡿࡇ࡜ࡀࠊࠕỈࢆヲ⣽࡟ゎᯒࡍࡿ࡜࡜ࡶ࡟ࠊᅾ᮶㨶࡬⧅ࡀࡿ⌧≧ࡢ㣗≀⥙ࡀࡁࢀ࠸࡛㨶ࡀ㇏࠿࡛࠶ࡿࠖ⎔ቃࡢࡓࡵ࡟㔜せ࡛࠶ࡿ࡜⪃ࡢᵓ㐀ࢆㄪ࡭ࡓࠋ

࠼ࡽࢀࡓࠋ

⍇⍈†ὶᇦỈ≀㉁ᚠ⎔ࣔࢹࣝࢆ⏝࠸ࡓ⤖ᯝ࠿ࡽࡣࠊ࿧྾
ຠ⋡࡟ࡘ࠸࡚ࡣᏘ⠇ኚືࡀᑡ࡞࠸ࡇ࡜ࠊ㌿᥮ຠ⋡ࡣ᫂░࡞Ꮨ⠇ᛶࡀ࠶ࡿࡇ࡜࡞࡝ࡀ♧၀ࡉࢀࡓࠋ

 ᪉ἲ
 ⏕≀᥇ྲྀ࡜Ᏻᐃྠ఩యศᯒ
⏕⏘⪅࡜ື≀ࣉࣛࣥࢡࢺࣥࡣࠊ2017㹼2019 ᖺ࡟⍇⍈†໭†Ἀᖏࡢ༡ẚⰋἈ୰ኸ㸦12B, Ỉ῝⣙ 60 m㸧࡛᥇ྲྀࡋࡓࠋ

 Ἀᖏࡢ㣗≀⥙ᵓ㐀࠿ࡽࡳࡓ㨶㢮࡬ࡢ㣵㈨※ホ౯

᥇ྲྀࡣࠊ2017 ᖺ࡛ࡣ 7 ᭶ࠊ9 ᭶ࠊ10 ᭶࡟ 1 ᅇࡎࡘ⾜࠸ࠊ2018 ᖺ࡜ 2019 ᖺ࡛ࡣࠊ1 ᖺࢆ㏻ࡋ࡚ࠊ㝸᭶ 1 ᅇ࠶ࡿ࠸ࡣ
ẖ᭶ 1 ᅇࡢ㢖ᗘ࡛⾜ࡗࡓࠋᮏ◊✲࡛ࡣࠊ⏕⏘⪅ࢆ⸴㢮ࡸᚤ ࡣࡌࡵ࡟

⏕≀ࡢ⢏Ꮚែ᭷ᶵ≀࡜ࡋࠊࡑࢀࢆ⸴㢮࡜ᚤ⏕≀࡟ศࡅࡿࡇ

⍇⍈†࡟࠾࠸࡚ࠊ࢔ࣘࡸ࣍ࣥࣔࣟࢥ➼ࡢᅾ᮶㨶ࢆᨭ࠼ࡿ࡜ࡣ୙ྍ⬟࡞ࡓࡵࠊ⸴㢮࡜ᚤ⏕≀ࢆࡲ࡜ࡵ࡚⏕⏘⪅࡜ࡋ࡚㣵ࡣࠊ࣑ࢪࣥࢥ㢮ࡸࢣ࣑ࣥࢪࣥࢥ㢮➼ࡢື≀ࣉࣛࣥࢡࢺࣥ

ᢅࡗࡓࠋ⏕⏘⪅ࡣࠊ⾲ᒙỈ࠿ࡽ᥇ྲྀࡋࠊື≀ࣉࣛࣥࢡࢺࣥ

࡛࠶ࡿ㸦༓ⴥࡽࠊ1987㸹Kawabata et al., 2006㸧ࠋᅾ᮶㨶ࡢྛ

ࡣࠊ࣓ࢵࢩࣗࢧ࢖ࢬࡀ 100 Pm ࡢࣉࣛࣥࢡࢺࣥࢿࢵࢺࢆ 0㨶✀࡟ࡣࠊ㣵ࡢዲࡳࡀ࠶ࡾࠊ౛࠼ࡤ࢔ࣘࡣ࢝ࣈࢺ࣑ࢪࣥࢥ

㹼10 m ࡲ࡛㖄┤ᘬࡁࡍࡿࡇ࡜࡛᥇ྲྀࡋࡓࠋᮏ◊✲࡛ࡣࠊࢆዲࢇ࡛ᤕ㣗ࡍࡿ㸦Kawabata et al., 2006㸧
ࠋ୍᪉ࠊື≀ࣉࣛᅾ᮶㨶࡜ࡋ࡚ࠊ⍇⍈†⁺ᴗ࡛㔜せ࡞࢔ࣘ࡜࣍ࣥࣔࣟࢥ࡟╔ࣥࢡࢺࣥࡣࠊ᳜≀ࣉࣛࣥࢡࢺࣥ㸦௨㝆ࠊ⸴㢮࡜ࡍࡿ㸧ࡸᚤ┠ࡋࡓࠋ࢔ࣘࡣࠊ2018 ᖺ࡜ 2019 ᖺࡢ 7 ᭶࡟Ἀࡍࡃ࠸⁺࡛⏕≀㸦⣽⳦ࡸཎ⏕ື≀㸧࡜࠸ࡗࡓ⏕⏘⪅ࢆ㣵࡟ࡍࡿࠋື≀᥇ྲྀࡋࡓಶయࢆࠊ࣍ࣥࣔࣟࢥࡣࠊ2018 ᖺ࡜ 2019 ᖺࡢ 10 ᭶ࣉࣛࣥࢡࢺࣥࡣࠊᦤ㣗࡛ࡁࡿ㣵ࡢࢧ࢖ࢬ⠊ᅖࡀࠊ✀ࡈ࡜࡟࡟Ἀ᭥ࡁ⥙⁺࡛᥇ྲྀࡋࡓಶయࢆሀ⏣⁺ᴗ༠ྠ⤌ྜ࠿ࡽ㉎

␗࡞ࡿ㸦Reynolds, 1984㸧ࠋྛ㨶✀ࡢ㣵ࡢዲࡳ࡜ࠊື≀ࣉࣛධࡋࡓࠋ୧㨶✀࡜ࡶࠊ໭†ࡢἈᖏ࡛ᤕࢀࡓࠕᡂ㨶ࠖࢆᏳᐃࣥࢡࢺࣥࡢ✀ࡈ࡜࡟␗࡞ࡿ㣵ࡢࢧ࢖ࢬ⠊ᅖ࡟ࡼࡾࠊ⏕⏘⪅ྠ఩యࡢศᯒヨᩱ࡟౑⏝ࡋࡓࠋ㸫ື≀ࣉࣛࣥࢡࢺࣥ㸫ᅾ᮶㨶࡬࡜⧅ࡀࡿ㣵ࡢ⤒㊰㸦㣗≀⥙ື≀ࣉࣛࣥࢡࢺࣥࡢ㣵ࡢࢧ࢖ࢬ⠊ᅖࡣ✀ࡈ࡜࡟␗࡞ࡿ

ࡢᵓ㐀㸧ࡣࠊ」㞧࡟࡞ࡗ࡚࠸ࡿࠋࡼࡗ࡚ࠊᅾ᮶㨶࡬ࡢ㣵ࡢࡇ࡜ ࠿ࡽࠊ᥇ྲྀࡋ ࡓ⏕⏘⪅ࢆࠊUrabe et al.㸦1996㸧࡜ᙳ㡪ホ౯࡟ࡣࠊ➨୍࡟ࠊྛ㨶✀࡬࡜⧅ࡀࡿ㣗≀⥙ࡢᵓ㐀ࢆ

Brönmark and Hansson㸦2018㸧ࢆཧ⪃࡟ࠊ3 ࡘࡢࢧ࢖ࢬ㸦<20,ᢕᥱࡍࡿࡇ࡜ࡀ୙ྍḞ࡛࠶ࡿࠋ

20-45, 45-250 Pm㸧࡟ศ⏬ࡋࡓࠋࡑࡢࢧ࢖ࢬศ⏬࡟ࡣࠊ࣓ࢵ

2016 ᖺ௨㝆ࠊ⍇⍈†࡛ࡣࠊ⣽⬊ࢧ࢖ࢬࡀ኱ࡁ࠸⸴㢮ࠊ࣑ࢩࣗࢧ࢖ࢬࡀ 20 Pm ࡜ 45 Pm ࡢ⠠ࢆ౑ࡗࡓࠋ㏆ᖺࠊ⍇⍈ࢡࣛࢫࢸࣜ࢔ࢫ㸦Micrasterias hardyi㸧ࡸࠊࢫࢱ࢘ࣛࢫࢺࣝ

†࡛኱Ⓨ⏕ࡋጞࡵࡓ࣑ࢡࣛࢫࢸࣜ࢔ࢫ࡜ࢫࢱ࢘ࣛࢫࢺࣝ

࣒㸦Staurastrum dorsidentiferum㸧ࡀ㢖⦾࡟኱Ⓨ⏕ࡍࡿࡼ࠺

࣒ࡣࠊ45-250 Pm ࡢࢧ࢖ࢬศ⏬࡟ྵࡲࢀࡿࠋྛࢧ࢖ࢬ࡟ศ

࡟࡞ࡗࡓ㸦Hodoki et al., 2020㸹⁠㈡┴⍇⍈†⎔ቃ㒊ࠊ2020㸧ࠋ⏬ࡋࡓ†Ỉ 0.35㹼12 L ࡟ྵࡲࢀࡿ⏕⏘⪅ࢆࠊணࡵ 5 ᫬㛫ࡇࡢᵝ࡞኱ᆺ⸴㢮ࡣࠊື≀ࣉࣛࣥࢡࢺࣥࡢྍ㣗ࢧ࢖ࢬࡼࡾ

450 oC ࡛⇕ฎ⌮ࡋࡓ GF/F ࣇ࢕ࣝࢱ࣮㸦Whatman㸧ୖ࡟ᤕ኱ࡁ࠸ࡇ࡜࠿ࡽ㸦Reynolds, 1984㸧
ࠊື≀ࣉࣛࣥࢡࢺࣥࡢ㣵㞟ࡋࠊ40 oC ࡛஝⇱ࡉࡏࡓࠋࣇ࢕ࣝࢱ࣮ୖ࡛஝⇱ࡉࡏࡓᚋࠊ

࡟ࡣ࡞ࡾ࡟ࡃ࠸࡜ண᝿ࡉࢀࡿ㸦࣑ࢡࣛࢫࢸࣜ࢔ࢫࡣ⣙ 200⏕⏘⪅ࡢⅣ⣲࣭❅⣲Ᏻᐃྠ఩యࢆࠊி㒔኱Ꮫ⏕ែᏛ◊✲ࢭPm, ࢫࢱ࢘ࣛࢫࢺ࣒ࣝࡣ⣙ 65 Pm㸧ࠋࡶࡋࠊື≀ࣉࣛࣥࢡࣥࢱ࣮ࡢඖ⣲ศᯒィ௜ࡁ㉁㔞ศᯒィ㸦Thermo Fisher ♫,ࢺࣥࡢ㣵࡟࡞ࡽ࡞࠸࡞ࡽࠊ኱ᆺ⸴㢮ࡣࠊᅾ᮶㨶࡬⧅ࡀࡿ㣗

DELTA V plusࠊࡶࡋࡃࡣ DELTA V advantage㸧࡛ᐃࡋࡓࠋ≀⥙࠿ࡽࡣእࢀࡓᏑᅾ࡜࡞ࡿࠋࡲࡓࠊᙼࡽࡢ኱Ⓨ⏕࡛௚⸴ᮏ◊✲࡛ࡣࠊ>250 Pm ࡢື≀ࣉࣛࣥࢡࢺ࡛ࣥ࠶ࡿ࣑ࢪࣥ

㢮ࡢࡓࡵࡢᰤ㣴ሷࡀዣࢃࢀࠊᅾ᮶㨶࡬Ώࡿࡣࡎ࡛࠶ࡗࡓᰤ

ࢥ㢮࡜ࢣ࣑ࣥࢪࣥࢥ㢮࡟╔┠ࡋࡓࠋ᥇ྲྀࡋࡓື≀ࣉࣛࣥࢡ㣴⣲➼ࡢ㔞ࡀῶࡗ࡚࠸ࡿྍ⬟ᛶࡀ࠶ࡿࠋࡋ࠿ࡋࠊ኱ᆺ⸴㢮ࢺࣥࡢ୰࠿ࡽࠊ⍇⍈†࡛ከࡃぢࡽࢀࡿ࢝ࣈࢺ࣑ࢪࣥࢥ

ࡀ኱Ⓨ⏕ࡍࡿࡼ࠺࡟࡞ࡗࡓ㏆ᖺࡢ⍇⍈†࡟࠾࠸࡚ࠊ኱ᆺ⸴

㸦Daphnia galeata㸧ࠊࣉࣜ࢝ࣜ࢔㸦D. pulicaria㸧ࠊ࣐ࣖࢺࣄ㢮࡜ື≀ࣉࣛࣥࢡࢺࣥ࡜ࡢ㛵ಀゎᯒࡸࠊᅾ᮶㨶࡬⧅ࡀࡿ㣗ࢤࢼ࢞ࢣ࣑ࣥࢪࣥࢥ㸦Eodiaptomus japonicus㸧ࠊࢣ࣑ࣥࢪࣥ

≀⥙ࡢᵓ㐀ࢆゎᯒࡋࡓ◊✲ࡣ࡞࠸ࠋࡑࡇ࡛ᮏ◊✲࡛ࡣࠊ኱

ࢥ㢮㸦Cyclopoida㸧ࢆ✀ࡈ࡜࡟ࣃࢫࢶ࣮ࣝࣆ࣌ࢵࢺࡸࣆࣥ

ᆺ⸴㢮ࡀࠊᅾ᮶㨶࡬⧅ࡀࡿ㣗≀⥙࠿ࡽ㐓⬺ࡋ࡚࠸ࡿ࠿ྰ࠿

ࢭࢵࢺ࡛ 150㹼200 ಶయࡎࡘᣠ࠸ฟࡋࠊ㉸⣧Ỉ㸦Milli-Q Ỉ㸧

⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮◊✲ሗ࿌᭩➨ 16 ྕ61࡛Ὑίࡋࡓ㸦Cyclopoida ࡢࡳ┠࡛ࣞ࣋ࣝศ㢮ࡋࡓ㸧ࠋὙίᶆ‽೫ᕪࢆ⏝࠸ࡓࠋᰤ㣴ẁ㝵ࡀ 1 ࡘୖࡀࡿࡈ࡜㸦ື≀ࣉࣛࡋࡓྛ✀ࡢື≀ࣉࣛࣥࢡࢺࣥࡣࠊ✀ࡈ࡜࡟ࢫࢬ࢝ࢵࣉ

ࣥࢡࢺࣥЍᅾ᮶㨶㸧ࡢᏳᐃྠ఩యẚࡢ⃰⦰ಀᩘࡣࠊⅣ⣲ࡀ㸦SÄNTIS analytical㸧࡟ධࢀࠊ40

oC ࡛஝⇱ࡉࡏࡓࠋ஝⇱ࡉ

0.4 ± 1.3‰ࠊ❅⣲ࡀ 3.42 r 0.99‰࡜ࡋࡓ㸦Post, 2002㸧ࠋࡏࡓື≀ࣉࣛࣥࢡࢺࣥࡢⅣ⣲࣭❅⣲Ᏻᐃྠ఩యࢆࠊ⏕⏘⪅࡜ྠࡌᶵჾ࡛

 ⤖ᯝᐃࡋࡓࠋ ᮏ◊✲࡛ࡣࠊ࢔ࣘ࡜࣍ࣥࣔࣟࢥࢆࠊయ㛗࡛ࡑࢀࡒࢀ 3 ࡘ⏕⏘⪅ࡢG13C ࡣࠊ-31.3㹼-13.4‰ࡢ⠊ᅖࢆኚືࡋ࡚࠾ࡾࠊ

࡟ศ㢮ࡋࡓ㸦࢔ࣘ㸸኱㸻>8 cmࠊ୰㸻7-8 cmࠊᑠ㸻<7 cm㸹

ẖᖺ 5㹼7 ᭶࡟㧗ࡃ࡞ࡿഴྥࡀ࠶ࡗࡓ㸦ᅗ 3-1㸧ࠋ⣽⬊ࢧ࢖࣍ࣥࣔࣟࢥ㸸኱㸻>10 cmࠊ୰㸻7-10 cmࠊᑠ㸻<7 cm㸧ࠋྛࢬู࡟ࡳࡿ࡜ࠊ<20 Pm ࡜ 20-45 Pm ࡣྠ⛬ᗘࡢ್࡛᥎⛣ࢧ࢖ࢬࡢ࢔ࣘ࡜࣍ࣥࣔࣟࢥࡣࠊ㢌࡜⫼㫅ࡢ㛫ࡢ⫗ࢆ࣓ࢫ࡛ࡋ࡚࠸ࡓࡢ࡟ᑐࡋࠊ45-250 Pm ࡣࡑࢀࡽࡼࡾࡶ㧗࠸್ࡔࡗษࡾྲྀࡾ㸦⓶࡜㦵ࡣ㝖ཤ㸧ࠊࡑࢀࢆ࣮࢜ࢺࢡ࣮ࣞࣈ⁛⳦῭ࡓࠋ୍᪉ࠊ⏕⏘⪅ࡢG15N ࡣࠊ2.6㹼8.6‰ࡢ⠊ᅖࢆኚືࡋ࡚

ࡳࡢ 1.7 mL ࣜࣥࢢࣟࢵࢡࢳ࣮ࣗࣈ㸦BMBio㸧࡟ධࢀࠊ40࠾ࡾࠊࡑࡢኚື࡟Ꮨ⠇ⓗ࡞ഴྥࡣࡳࡽࢀ࡞࠿ࡗࡓࠋ⣽⬊ࢧoC ࡛஝⇱ࡉࡏࡓࠋ஝⇱ࡉࡏࡓ⫗ࡣࠊ⢊ᮎ࡟ࡋࡓᚋࠊࢫࢬ࢝

࢖ࢬู࡟ࡳ࡚ࡶࠊ࡝ࡢࢧ࢖ࢬࡶྠ⛬ᗘࡢ್࡛᥎⛣ࡋ࡚࠸ࡓࢵࣉ࡟ධࢀ࡚Ⅳ⣲࣭❅⣲Ᏻᐃྠ఩యࡢศᯒヨᩱ࡜ࡋࡓࠋ୧

㸦ᅗ 3-1㸧ࠋ㨶✀࡜ࡶࠊྛࢧ࢖ࢬ 5㹼10 ಶయࢆᏳᐃྠ఩యࡢศᯒヨᩱ࡟౑⏝ࡋࡓࠋᏳᐃྠ఩యࡢศᯒࡣࠊ⏕⏘⪅࡜ྠࡌᶵჾ࡛⾜ࡗࡓࠋ ྛࢧ࢖ࢬࡢ⏕⏘⪅ࠊྛ✀ࡢື≀ࣉࣛࣥࢡࢺࣥࠊྛࢧ࢖ࢬ
ࡢ࢔ࣘ࡜࣍ࣥࣔࣟࢥࡢᏳᐃྠ఩యẚࡣࠊᅜ㝿ᶆ‽≀㉁࡟ᑐ
ࡍࡿ༓ศ೫ᕪ㸦G್ࠊ༢఩‰㸧࡛⾲ࡋࡓ㸦ᘧ 1㸧ࠋࡇࢀ௨㝆ࡣࠊⅣ⣲Ᏻᐃྠ఩యẚࢆG13Cࠊ❅⣲Ᏻᐃྠ఩యẚࢆG15N ࡜ࡍࡿࠋ G13C or G15N = (R ヨᩱ/R ᅜ㝿ᶆ‽≀㉁) – 1] u 1000㸦ᘧ 1㸧
ࡇࡇ࡛ࠊR ࡣ 13C/12Cࠊࡲࡓࡣ 15N/14N ࢆ♧ࡍࠋᅜ㝿ᶆ‽≀㉁ ࡜ ࡋ࡚ ࠊ Ⅳ ⣲ࡣ Pee Dee ᒙ ࡢ ࣋ ࣝ ࣒ ࢼ ࢖ ࢺ Ⅳ 㓟 ሷ㸦VPDB㸸13C/12C = 0.011180㸧ࢆ⏝࠸ࠊ❅⣲ࡣ኱Ẽ୰ࡢ❅⣲࢞ࢫ㸦15N/14N = 0.0036765㸧ࢆ⏝࠸ࡓࠋ 㨶ࡢG13C ࡣࠊྵࡲࢀࡿ⬡㉁ࡢྵ᭷㔞࡟ࡼࡗ࡚ᙳ㡪ࢆཷࡅࠊㄗᕪࡀ⏕ࡌࡿࠋᮏ◊✲࡛ࡣࠊࡑࡢᙳ㡪ࢆ࡞ࡃࡍࡓࡵࠊ
ศᯒ࡛ᚓࡽࢀࡓ࢔ࣘ࡜࣍ࣥࣔࣟࢥࡢG13C ࢆࠊࡑࢀࡒࢀἑ⏣ࡽ㸦2018㸧࡜ Logan et al.㸦2008㸧ࡢᘧ࡟ࡼࡗ࡚⿵ṇࡋࡓࠋ ࢔ࣘ࡜࣍ࣥࣔࣟࢥࡢ㣵㑅ᢥᛶࡢゎᯒᅗ  㹼 ᖺࡢ໭†Ἀᖏ࡟࠾ࡅࡿ⏕⏘⪅ࡢG& ᮏ◊✲࡛ࡣࠊ⍇⍈†ࡢ࢔ࣘ࡜࣍ࣥࣔࣟࢥࡢ㣵ࡣࠊ࣑ࢪࣥ

㸦ୖᅗ㸧࡜G1㸦ୗᅗ㸧ࡢኚ໬ᖹᆒr6'ࢥ㢮ࡸࢣ࣑ࣥࢪࣥࢥ㢮➼ࡢື≀ࣉࣛࣥࢡࢺࣥ࡜ࡋ㸦༓ⴥࡽࠊ
1987㸹Kawabata et al., 2006㸧ࠊྛ✀ࡢື≀ࣉࣛࣥࢡࢺࣥࠊ࢔

ື≀ࣉࣛࣥࢡࢺࣥࡢG13C ࡣࠊ✀࡟ࡼࡗ࡚࡯࡜ࢇ࡝ᕪࡀ࡞

ࣘࠊ࣍ࣥࣔࣟࢥࡢG13C ࡜G15N ࠿ࡽࠊ࢔ࣘ࡜࣍ࣥࣔࣟࢥࡢ

࠿ࡗࡓ㸦ᅗ 3-2㸧ࠋࡑࡢ್ࡣࠊ-35.5㹼-16.7‰ࡢ⠊ᅖࢆኚືࡋ

㣵㑅ᢥᛶࢆゎᯒࡋࡓࠋ㣵㑅ᢥᛶࡢゎᯒࡣࠊΰྜࣔࢹ࡛ࣝ⾜࡚࠾ࡾࠊẖᖺ 6 ᭶࡜ 7 ᭶࡟㧗ࡃ࡞ࡿഴྥࡀ࠶ࡗࡓࠋྛ✀ࡢ

࠸ࠊR version 3.6.0㸦R Development Core Team㸧ࡢ SIAR ࣃື≀ࣉࣛࣥࢡࢺࣥࡢG13C ࡣࠊ<20 Pm ࡸ 20-45 Pm ⏕⏘⪅ࡢࢵࢣ࣮ࢪࢆ⏝࠸ࡓࠋ㨶ࡢᏳᐃྠ఩యẚࡢ⨨᥮㏿ᗘࡣࠊ⣙ 3್࡟⃰⦰ಀᩘࢆ㊊ࡋࡓ⠊ᅖ࡟ࠊ࡯࡜ࢇ࡝ධࡗ࡚࠸ࡓࠋ୍᪉ࠊ

࠿᭶࡜⪃࠼ࡽࢀ࡚࠸ࡿࡇ࡜࠿ࡽ㸦Busst and Britton, 2018㸹

G15N ࡟ࡘ࠸࡚ࡣࠊ࢝ࣈࢺ࣑ࢪࣥࢥ࡜ࣉࣜ࢝ࣜ࢔ࠊ࣐ࣖࢺࣄ

Winter et al., 2019㸧ࠊ㣵㑅ᢥᛶࡢゎᯒ࡟ࡣࠊ㣵ࡢື≀ࣉࣛࣥࢤࢼ࢞ࢣ࣑ࣥࢪࣥࢥ࡜ࢣ࣑ࣥࢪࣥࢥ㢮ࡀࠊࡑࢀࡒࢀྠ⛬ᗘ

ࢡࢺࣥࡢG13C ࡸG15N ࡜ࡋ࡚ࠊ3 ࠿᭶ࡢᖹᆒ್࡜ᶆ‽೫ᕪࢆࡢ್࡛᥎⛣ࡋ࡚࠾ࡾࠊᚋ⪅ࡢ 2 ✀ࡢ᪉ࡀࠊ๓⪅ࡼࡾࡶ㧗࠿౑⏝ࡋࡓࠋ7 ᭶࡟᥇ྲྀࡋࡓ࢔ࣘࡢ㣵㑅ᢥᛶࡢゎᯒ࡟ࡣࠊ5ࡗࡓ㸦ᅗ 3-2ࠊ࣮࢝ࣛᅗ⾲ཧ↷㸧ࠋᏘ⠇ⓗ࡟ࡣࠊࡍ࡭࡚ࡢ✀13

㹼7 ᭶ࡢື≀ࣉࣛࣥࢡࢺࣥࡢG C ࡸG N ࡢᖹᆒ್࡜ᶆ‽ࡢG15N ࡣࠊ5 ᭶㹼7 ᭶࡟㧗ࡃ࡞ࡿഴྥࡀ࠶ࡗࡓࠋ࢝ࣈࢺ࣑

೫ᕪࢆࠊ10 ᭶࡟᥇ྲྀࡋࡓ࣍ࣥࣔࣟࢥࡢ㣵㑅ᢥᛶࡢゎᯒ࡟ࢪࣥࢥ࡜ࣉࣜ࢝ࣜ࢔ࡢG15N ࡣࠊ1㹼4 ᭶࡜ࠊ8㹼12 ᭶࡟ࡣྛࡣࠊ8㹼10 ᭶ࡢື≀ࣉࣛࣥࢡࢺࣥࡢG13C ࡸG15N ࡢᖹᆒ್࡜

ࢧ࢖ࢬࡢ⏕⏘⪅ࡢ್࡟⃰⦰ಀᩘࢆ㊊ࡋࡓ⠊ᅖ࡟࡯ࡰධࡗ

62

15⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ヨ㦂◊✲ሗ࿌᭩➨ 16 ྕ࡚࠸ࡓࡀࠊ5 ᭶㹼7 ᭶࡟ࡣࡑࡢ⠊ᅖࡼࡾ㧗ࡃ࡞ࡿഴྥࡀ࠶

2018 ᖺ 7 ᭶࡜ 2019 ᖺ 7 ᭶࡟ᤕࢀࡓ࢔ࣘࡢG15N ࡣࠊ୧ᖺࡗࡓࠋ࣐ࣖࢺࣄࢤࢼ࢞ࢣ࣑ࣥࢪࣥࢥ࡜ࢣ࣑ࣥࢪࣥࢥ㢮ࡢ

ࡢ 5㹼7 ᭶ࡢࣄࢤࢼ࢞ࢣ࣑ࣥࢪࣥࢥ࡜ࢣ࣑ࣥࢪࣥࢥ㢮ࡢᖹ

Gᆒ್ࡼࡾప࠿ࡗࡓ㸦ᅗ 3-3㸧ࠋࡼࡗ࡚ࠊ୧ᖺࡢ 5㹼7 ᭶࡟࠾

15Nࡣࠊྛࢧ࢖ࢬࡢ⏕⏘⪅ࡢ್࡟⃰⦰ಀᩘࢆ㊊ࡋࡓ⠊ᅖ࠸࡚ࠊ࢔ࣘࡀୖグ 2 ✀㢮ࡢື≀ࣉࣛࣥࢡࢺࣥࢆᤕ㣗ࡋ࡚࠸࡟ẚ࡭࡚ࠊ࡝ࡢᏘ⠇࡛ࡶ㧗࠿ࡗࡓࠋࡓ࡜ࡣ⪃࠼ࡽࢀ࡞࠿ࡗࡓࡓࡵࠊΰྜࣔࢹࣝ࡟ࡼࡿ࢔ࣘࡢ㣵㑅ᢥᛶࡢゎᯒ࡛ࡣࠊ࢔ࣘࡢ㣵࠿ࡽࡑࡢ 2 ✀㢮ࢆ㝖እࡋࡓࠋ࢔ࣘࡢ㣵㑅ᢥᛶࢆゎᯒࡋࡓ⤖ᯝࠊ2018 ᖺ 7 ᭶࡜ 2019 ᖺ 7᭶ࡢ࢔ࣘࡢG13C ࡜G15N ࡣࠊྛᖺ 5㹼7 ᭶ࡢ࢝ࣈࢺ࣑ࢪࣥࢥ
࡜ࣉࣜ࢝ࣜ࢔ࡢ್࡛᭷ព࡟ㄝ࡛᫂ࡁ㸦95%࣋࢖ࢬಙ⏝༊㛫
>0㸧
ࠊ2 ✀ࢆࡑࢀࡒࢀᖹᆒ⣙ 50%ࡢ๭ྜ࡛㣵࡟ࡋ࡚࠸ࡓࠋ
࢔ࣘࡢ㣵㑅ᢥᛶ࡟ࡣࠊయࢧ࢖ࢬ࡟ࡼࡿ㐪࠸ࡣ࡞࠿ࡗࡓࠋ ࣍ࣥࣔࣟࢥࡢ㣵㑅ᢥᛶࢆゎᯒࡋࡓ⤖ᯝࠊ2019 ᖺ 10 ᭶ࡢ࣍ࣥࣔࣟࢥࡢG13C ࡜G15N ࡣࠊ8㹼10 ᭶ࡢ࢝ࣈࢺ࣑ࢪࣥࢥࠊ
࣐ࣖࢺࣄࢤࢼ࢞ࢣ࣑ࣥࢪࣥࢥࠊࢣ࣑ࣥࢪࣥࢥ㢮ࡢ್࡛ 70
㹼90%ࡲ࡛ㄝ࡛᫂ࡁࡓࠋ㣵㑅ᢥᛶ࡜ࡋ࡚ࡣࠊ࣍ࣥࣔࣟࢥࡢ
㣵ࡢ 50㹼60%ࡣ࢝ࣈࢺ࣑ࢪࣥࢥ࡛࠶ࡾࠊ<30%ࡀ࣐ࣖࢺࣄ
ࢤࢼ࢞ࢣ࣑ࣥࢪࣥࢥ࡜ࢣ࣑ࣥࢪࣥࢥ㢮࡛࠶ࡗࡓࠋṧࡾ 10
㹼30%ࡣࠊᮏ◊✲࡛ࡣㄪ࡭࡞࠿ࡗࡓ㣵࡛࠶ࡗࡓࠋ࣍ࣥࣔࣟ
ࢥࡢ㣵㑅ᢥᛶ࡟ࡣࠊయࢧ࢖ࢬ࡟ࡼࡿ㐪࠸ࡣ࡞࠿ࡗࡓࠋ୍᪉ࠊ
2018 ᖺ 10 ᭶ࡢ࣍ࣥࣔࣟࢥࡢ㣵㑅ᢥᛶࡣࠊ㣵⏕≀ࡢG13C ࡜
G15N ࡢࢹ࣮ࢱᩘࡀᑡ࡞࠿ࡗࡓࡓࡵࠊ⟬ฟ࡛ࡁ࡞࠿ࡗࡓࠋ
 ⪃ᐹᮏ◊✲࡛ࡣࠊ㏆ᖺ࡟⍇⍈†࡛኱Ⓨ⏕ࡋጞࡵࡓ኱ᆺ⸴㢮ࡀࠊᅾ᮶㨶࡬⧅ࡀࡿ㣗≀⥙࠿ࡽ㐓⬺ࡋ࡚࠸ࡿ࠿ྰ࠿ࢆホ౯ࡍᅗ  㹼 ᖺࡢ໭†Ἀᖏ࡟࠾ࡅࡿື≀ࣉࣛࣥࢡࡿࡓࡵࠊG13C ࡜G15N ࡟ࡼࡾࠊྛࢧ࢖ࢬࡢ⏕⏘⪅࡜ື≀ࣉ

ࢺࣥࡢG &㸦ୖᅗ㸧࡜G 1㸦ୗᅗ㸧ࡢኚ໬‫ࢪ࣑ࢺࣈ࢝ࡣە‬ࣛࣥࢡࢺࣥ࡜ࡢ㛵ಀࢆヲ⣽࡟ゎᯒࡍࡿ࡜࡜ࡶ࡟ࠊ࢔ࣘ࡜࣍

ࣥࢥࠊ‫ࠊࢥࣥࢪ࣑ࣥࢣ࢞ࢼࢤࣄࢺ࣐ࣖࡣۂࠊ࢔ࣜ࢝ࣜࣉࡣۑ‬ࣥࣔࣟࢥ࡬⧅ࡀࡿ⌧≧ࡢ㣗≀⥙ࡢᵓ㐀ࢆㄪ࡭ࡓ㸦኱ᆺ⸴㢮‫ࢥࣥࢪ࣑ࣥࢣࡣڹ‬㢮 ᖹᆒr6' ᖏ≧ࡢᢡࢀ⥺ࡣࠊࡑࢀࡣ኱ᆺ⏕⏘⪅࡟ྵࡲࢀࡿ㸧ࠋᮏ◊✲ࡢᵝ࡟ࠊྛࢧ࢖ࢬࡢ⏕ࡒࢀPPࠊPPࠊPP ࡢ⏕⏘⪅ࡢG & ࡸG 1⏘⪅࡜ື≀ࣉࣛࣥࢡࢺࣥࡢG13C ࡜G15N ࢆ 2 ᖺ௨ୖ࡟Ώࡗ

࡟⃰⦰ಀᩘ㸦3RVW㸧ࢆ㊊ࡋࡓ⠊ᅖ㸦࣮࢝ࣛᅗ⾲ཧ↷㸧࡚ศᯒࡋࡓ◊✲ࡣࠊ⍇⍈†࡛ࡣ࡞࠸㸦ᅜෆࡢ௚†࡛ࡶ࡞࠸㸧ࠋ

ࡼࡗ࡚ࠊヲ⣽࡞G13C ࡜G15N ࢹ࣮ࢱ࡟ࡼࡾࠊ኱ᆺ⸴㢮࡜ື
G13C ࡜G15N ࠿ࡽࠊ2018 ᖺ 7 ᭶࡜ 2019 ᖺ 7 ᭶ࡢ࢔ࣘ࡬⧅

≀ࣉࣛࣥࢡࢺࣥ࡜ࡢ㛵ಀࡸࠊ࢔ࣘࡸ࣍ࣥࣔࣟࢥ࡬⧅ࡀࡿ㣗ࡀࡿ㣗≀⥙ࡢᵓ㐀ࢆㄪ࡭ࡓ⤖ᯝࠊ<20 Pm ࡸ 20-45 Pm ࡢ୰≀⥙࡜ࡢ㛵ಀࢆホ౯ࡋࡓᮏ◊✲ࡢ⤖ᯝࡣࠊ㏆ᖺࡢ⍇⍈†⏕ᑠᆺࡢ⏕⏘⪅ࡀ㉳Ⅼ࡜࡞ࡗ࡚࠸ࡓ㸦ᅗ 3-3㸧ࠋ୍᪉ࠊ࣑ࢡࣛ

ែ⣔ࢆ⌮ゎࡍࡿ࠺࠼࡛㈗㔜࡛࠶ࡿࠋᮏ◊✲࡛ᚓࡽࢀࡓ⤖ᯝࢫࢸࣜ࢔ࢫࡸࢫࢱ࢘ࣛࢫࢺ࣒ࣝࡀྵࡲࢀࡿ 45-250 Pm ࡢ࡟ࡘ࠸࡚ࠊḟ࠿ࡽ㡯┠ࡈ࡜࡟⪃ᐹࡍࡿࠋ኱ᆺ⏕⏘⪅ࡢG13

C ࡣࠊ୧ᖺ࡜ࡶ࢔ࣘ࡬⧅ࡀࡿ㣗≀⥙࠿ࡽࡣእࢀ࡚࠸ࡓࠋ୧ᖺ࡜ࡶࠊ࢔ࣘࡢG13C ࡜G15N ࡣࠊయ㛗࡛ࡑࢀ ⏕⏘⪅࡟ࡘ࠸࡚ᮏ◊✲ࡢ⤖ᯝ࠿ࡽࠊ⏕⏘⪅ࡢG15N ࡣࠊ⣽⬊ࢧ࢖ࢬ࡛ࡣᕪ

⛬ᕪࡣ࡞࠿ࡗࡓࠋ
G13C ࡜G15N ࠿ࡽࠊ2018 ᖺ 10 ᭶࡜ 2019 ᖺ 10 ᭶ࡢ࣍ࣥࣔ

ࡀ࡞࠿ࡗࡓ㸦ᅗ 3-1㸧ࠋࡇࢀࡣࠊ඲࡚ࡢࢧ࢖ࢬࡢࡶࡢࡀࠊྠ

ࣟࢥ࡬⧅ࡀࡿ㣗≀⥙ࡢᵓ㐀ࢆㄪ࡭ࡓ⤖ᯝࠊ࢔ࣘࡢሙྜ࡜ྠ

ࡌᰤ㣴ẁ㝵࡟ᒓࡍࡿ⏕⏘⪅࡛࠶ࡗࡓࡇ࡜ࢆ♧ࡍࠋ୍᪉ࠊ⏕ࡌࡃࠊ<20 Pm ࡸ 20-45 Pm ࡢ୰ᑠᆺࡢ⏕⏘⪅ࡀ㉳Ⅼ࡜࡞ࡗ⏘⪅ࡢG13C ࡣࠊࢧ࢖ࢬࡈ࡜࡛␗࡞ࡾࠊ45-250 Pm ࡢ኱ᆺࡢ࡚࠸ࡓ㸦ᅗ 3-4㸧ࠋࡲࡓࠊ45-250 Pm ࡢ኱ᆺ⏕⏘⪅ࡢG13C ࡣࠊ್ࡀࠊ<20 Pm ࡜ 20-45 Pm ࡢ୰ᑠᆺࡼࡾࡶ 1 ᖺࢆ㏻ࡋ࡚㧗୧ᖺ࡜ࡶ࣍ࣥࣔࣟࢥ࡬⧅ࡀࡿ㣗≀⥙࠿ࡽࡣእࢀ࡚࠸ࡓࠋྛ

࠿ࡗࡓ㸦ᅗ 3-1㸧ࠋࡇࡢᕪࡣࠊ⏕⏘⪅ࡢቑṪ㏿ᗘࡀ✀㢮ࡸࢧࢧ࢖ࢬࡢ࣍ࣥࣔࣟࢥࡢG13C ࡜G15N ࡣࠊࡑࢀ⛬ᕪࡀ࡞࠿ࡗ

࢖ࢬ࡛␗࡞ࡗ࡚࠾ࡾࠊ኱ᆺࡢቑṪ㏿ᗘࡢ᪉ࡀ㧗࠿ࡗࡓ⤖ᯝࡓࠋ࡜⪃࠼ࡽࢀࡿ㸦Gearing et al., 1984㸹Takahashi et al., 1991㸧
ࠋ⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮◊✲ሗ࿌᭩➨ 16 ྕ

63

2018
䜿䞁䝭䝆䞁䝁
䝭䝆䝠䝀䝘䜺䜿䞁䝭䝆䞁䝁䝠䝀䝘䜺䝰䝻䝁䠄኱䠅
䝰
12 䝰䝻䝁䠄ᑠ䠅䠅 䝰䝰䝻䝁䠄୰䠅
14

G15N (‰)

G15N (‰)

20
2018
18
䜿䞁䝭䝆䞁䝁
䝁
16䝠䝀䝘䜺䜿䞁䝭䝆䞁䝁䜰䝴䠄ᑠ䠅䜰䝴䠄኱䠅䠅 䜰䝴䠄୰䠅
14䜰䜹䝤䝖䝭䝆䞁䝁
12
䝥䝸䜹䝸䜰
䝥
10
⏕⏘⪅
8
20-45Pm䠄⸴㢮➼䠖5, 6᭶䠅
6
<20Pm
0Pm
45-250Pm
4
-30
-25
-20
-15
-10
13
G C (‰)

2019

18

8
6

m
20-45Pm⏕⏘⏕⏘⪅䠄⸴㢮➼䠅

<20Pm
20

4
-30

-25

45-250Pm-20-15
G13C (‰)-10

G15N (‰)

G15N (‰)

10䝥䝸䜹䝸䜰䠄5, 6᭶䠅䜹䝤䝖䝭䝆䞁䝁
䞁䝁

8⏕⏘⪅䠄⸴㢮➼䠅
20-45Pmm
645-250Pm
<20Pm
4
-30
-25
-20
-15
-10
δ13C
(‰)
13
G C (‰)

14

䞁
䞁䝁
䜰䝴䠄ᑠ䠅
16 䜿䞁䝭䝆䞁䝁䜰䜰䝴䠄୰䠅䝠䝀䝘䜺䜿䞁䝭䝆䞁䝁
䜰
䜰䝴
䜰䝴䠄኱䠅
14

12

䜹䝤䝖䝭䝆䞁䝁䜹䜹䝤10䝰䝻䝁䠄ᑠ䠅䝰䝰䝻2019䝰䝻䝁䠄୰䠅䠄୰䠅䠄䠅䝰䝻䝁䠄኱䠅
12䝠䝀䝘䜺䜿䞁䝭䝆䞁䝁䝠䝀䜿䞁䝭䝆䞁䝁䜿䜿䞁10䜹䝤䝖䝭䝆䞁䝁
䜹
䜹䝤

8
20-45
020-45Pm

6
4

<20Pm

-30

-25

⏕⏘⪅䠄⸴㢮➼䠅
45-250Pm

-20

-15

-10

G13C (‰)

ᅗ   ᖺ  ᭶࡜  ᖺ  ᭶࡟໭†Ἀᖏ࡛ᤕࢀᅗ   ᖺ  ᭶࡜  ᖺ  ᭶ࡢ໭†Ἀᖏ࡛ᤕࡓ࢔ࣘ࡜ࠊ⏕⏘⪅࠾ࡼࡧື≀ࣉࣛࣥࢡࢺࣥࡢG& ࡜G1ࢀࡓ࣍ࣥࣔࣟࢥ࡜ࠊ⏕⏘⪅࠾ࡼࡧື≀ࣉࣛࣥࢡࢺࣥࡢ

ࡢ㛵ಀ ᖹᆒ r6' 㨶ࡢᏳᐃྠ఩యẚࡢ⨨᥮㏿ᗘ࡜

G& ࡜G1 ࡢ㛵ಀ ᖹᆒr6' 㨶ࡢᏳᐃྠ఩యẚࡢ⨨ࡢ㛵ಀ࠿ࡽࠊ⏕⏘⪅࡜ື≀ࣉࣛࣥࢡࢺࣥࡢ್ࡣࠊ㹼

᥮㏿ᗘ࡜ࡢ㛵ಀ࠿ࡽࠊ⏕⏘⪅࡜ື≀ࣉࣛࣥࢡࢺࣥࡢ್

᭶ࡢᖹᆒ್࡜ࡋࡓ ▮༳ࡣࠊG& ࡜G1 ࡢ⃰⦰ಀᩘ࠿ࡣࠊ㹼 ᭶ࡢᖹᆒ್࡜ࡋࡓ▮༳ࡣࠊG& ࡜G1 ࡢ⃰ࡽ᝿ᐃࡉࢀࡿ࢔ࣘ࡬⧅ࡀࡿ㣗≀⥙⦰ಀᩘ࠿ࡽ᝿ᐃࡉࢀࡿ࣍ࣥࣔࣟࢥ࡬⧅ࡀࡿ㣗≀⥙ᮏ◊✲࡜ྠᵝ࡟ࠊYamada et al.㸦1998㸧ࡣࠊ1993 ᖺ࡜ 1994ᖺࡢ໭†Ἀᖏ࡟࠾࠸࡚ࠊ
ྛࢧ࢖ࢬࡢ⏕⏘⪅ࡢG13C ࡜G15N ࢆㄪ࡭࡚࠸ࡿࠋᙼࡽࡢ⤖ᯝ࡛ࡣࠊ<40 Pm ࡢ⏕⏘⪅࡟ẚ࡭࡚ࠊ
>40 Pm ࡢ኱ᆺࡢG13C ࡀ㧗࠿ࡗࡓࡢࡣࠊኟ࠿ࡽ⛅ࡢ㛫ࡔࡅ࡛࠶ࡗࡓࠋ୍᪉ࠊᮏ◊✲ࡢ 2018 ᖺ࡜ 2019 ᖺ࡛ࡣࠊ1 ᖺࢆ
㏻ࡋ࡚ࠊ45-250 Pm ࡢ኱ᆺࡢG C ࡀ㧗࠿ࡗࡓࠋᮏ◊✲࡜
13

Yamada et al.㸦1998㸧ࡢ኱ࡁ࡞㐪࠸ࡣࠊ45-250 Pmࠊ࠶ࡿ࠸ࡣ>40 Pm ࡟ྵࡲࢀࡿ኱ᆺ⸴㢮ࡢ⌧Ꮡ㔞࡛࠶ࡿࠋYamada et ࣑ࢪࣥࢥ㢮ࡢ㣵࡟ࡘ࠸࡚ ࢝ࣈࢺ࣑ࢪࣥࢥࡸࣉࣜ࢝ࣜ࢔࡜࠸ࡗࡓ Daphnia ᒓࡢ࣑ࢪࣥࢥࡣࠊ୺࡟ 1㹼50 Pm ࡢ⸴㢮ࢆ㣗࡭ࡿ୍ḟᾘ㈝⪅࡜⪃࠼ࡽࢀ࡚࠸ࡿ㸦Reynolds, 1984㸹Brönmark and Hansson, 2018㸧ࠋᮏ◊✲࡛ࡶࠊ࢝ࣈࢺ࣑ࢪࣥࢥ࡜ࣉࣜ࢝ࣜ࢔ࡢG13C ࡜G15N ࡣࠊ<20 Pm ࡸ 20-45 Pm ࡢ୰ᑠᆺ⏕⏘⪅ࡢ್࡟⃰⦰ಀᩘࢆ㊊ࡋࡓ⠊ᅖ࡟࡯࡜ࢇ࡝ධࡗ࡚࠾ࡾࠊࡑࡢ 2 ✀ࡢ࣑ࢪࣥࢥࡀࠊ୰
ᑠᆺࡢ⸴㢮➼ࢆ㣗࡭࡚࠸ࡓࡇ࡜ࢆ♧ࡍ⤖ᯝ࡜࡞ࡗࡓ㸦ᅗ 3-

al.㸦1998㸧࡛᫓࡜෤࡟ㄪᰝࢆ⾜ࡗࡓ 1994 ᖺ࡛ࡣࠊ2018 ᖺ2㸧ࠋࡇࢀ࡟ᑐࡋࠊ2 ✀ࡢ࣑ࢪࣥࢥࡢG13C ࡣࠊ45-250 Pm ࡢ࡜ 2019 ᖺ࡟ẚ࡭࡚ࠊ᫓࡜෤ࡢ኱ᆺ⸴㢮ࢫࢱ࢘ࣛࢫࢺ࣒ࣝ

኱ᆺ⏕⏘⪅ࡢ್࡟⃰⦰ಀᩘࢆ㊊ࡋࡓ⠊ᅖ࠿ࡽࡣእࢀ࡚࠾

ࡢ⌧Ꮡ㔞ࡀపࡃࠊࡲࡓ࣑ࢡࣛࢫࢸࣜ࢔ࢫࡶᏑᅾࡋ࡞࠸㸦୍ࡾࠊ኱ᆺ⏕⏘⪅ࢆ࡯࡜ࢇ࡝㣗࡭࡞࠸࡜⪃࠼ࡽࢀࡓࠋࡇࢀࡽ

℩ࡽࠊ2011㸹Kishimoto et al., 2013㸹Hodoki et al., 2020㸹⁠ࡢ࣑ࢪࣥࢥࡢ㣗ᛶ࡟㛵ࡍࡿ⤖ᯝࡣࠊከࡃࡢ᪤Ꮡ◊✲ࡢ⤖ᯝ

㈡┴⍇⍈†⎔ቃ㒊ࠊ2020㸧ࠋࡼࡗ࡚ࠊᮏ◊✲࡟࠾ࡅࡿ኱ᆺ

ࢆᨭᣢࡋ࡚࠸ࡿ㸦e.g. Yamada et al., 1998㸹Yoshida et al.,⏕⏘⪅ࡢ㧗࠸G13C ࡣࠊ㏆ᖺ࡛ࡣࠊ1 ᖺࢆ㏻ࡋ࡚኱ᆺ⸴㢮ࡢ

2001㸧
ࠋ୍᪉ࠊኟ࡟ࡣࠊ࢝ࣈࢺ࣑ࢪࣥࢥ࡜ࣉࣜ࢝ࣜ࢔ࡢG15N

ቑṪࡀࠊάⓎ࡟࡞ࡗ࡚࠸ࡿࡇ࡜ࢆ♧ࡋ࡚࠸ࡿ࡜⪃࠼ࡽࢀࡿࠋ

ࡀࠊ୰ᑠᆺ⏕⏘⪅ࡢ್࡟⃰⦰ಀᩘࢆ㊊ࡋࡓ⠊ᅖࢆ㉸࠼ࡿࡇ࡜ࡀ࠶ࡗࡓࠋࡇࡢ⌮⏤࡜ࡋ࡚ࡣࠊḟࡢ 2 ࡘࡀ⪃࠼ࡽࢀࡿࠋձ 㣵࠿ࡽ࣑ࢪࣥࢥࡢG15N ࡢ⃰⦰⋡ࡣࠊ㏻ᖖ 3.42 r 0.99‰64⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ヨ㦂◊✲ሗ࿌᭩➨ 16 ྕղࡔࡀ㸦3.2.2.ཧ↷㸧
ࠊC㸸N ࡢ㧗࠸㣵㸦㉁ࡢప࠸㣵㸧ࢆ࣑ᅾ࡛࠶ࡿࡇ࡜ࡀศ࠿ࡗࡓ㸦ᅗ 3-3㸧
ࠋ45-250 Pm ࡢ኱ᆺ⏕⏘15N ࡢ⃰⦰⋡ࡀ⣙ 6‰ࡲ࡛ୖࡀࡿ

ࢪࣥࢥࡀ㣗࡭ࡿ࡜ࠊG⪅࡟ࡣࠊ㏆ᖺ࡟኱Ⓨ⏕ࡍࡿࡼ࠺࡟࡞ࡗࡓ࣑ࢡࣛࢫࢸࣜ࢔ࢫ

15N ࡀୖ㸦Adams and Sterner, 2000㸧
ࠋኟ࡟࣑ࢪࣥࢥࡢG

ࡸࢫࢱ࢘ࣛࢫࢺ࣒ࣝࡀྵࡲࢀࡿࠋ࢔ࣘ࡬⧅ࡀࡿ㣗≀⥙࠿ࡽ᪼ࡍࡿࡢࡣࠊ㉁ࡢᝏ࠸㣵ࢆ㣗࡭࡚࠸ࡿࡇ࡜ࢆ♧ࡋ࡚࠸እࢀ࡚࠸ࡿ࡜࠸࠺ࡇ࡜ࡣࠊ኱ᆺ⸴㢮ࡀ୰ᑠᆺ⏕⏘⪅ࡢᰤ㣴ࡿࡢ࠿ࡶࡋࢀ࡞࠸ࠋ

ሷࢆዣ࠸ࠊ࢔ࣘ࡬Ώࡿࡣࡎࡢᰤ㣴⣲➼ࡢ㔞ࢆῶࡽࡋ࡚࠸ࡿ

⍇⍈†࡛ࡣࠊᮏ◊✲࡛ㄪᰝࡋࡓ⾲ᒙࡼࡾࠊ20 m ௨῝ྍ⬟ᛶࡀ࠶ࡿࠋ௒ᚋࠊࡑࡢࡼ࠺࡞ᰤ㣴⣲➼ࡢᦆኻࡀ⏕ࡌ࡚ࡢ᪉ࡀ⏕⏘⪅ࡢG15N ࡀ㧗࠸㸦Tanaka et al., 2010㸧ࠋኟ࠸ࡿࡢ࠿ࢆࠊヲ⣽࡞ㄪᰝ࣭ᐇ㦂࡛ㄪ࡭ࡿᚲせࡀ࠶ࡿࠋ

15࡟࣑ࢪࣥࢥࡢG N ࡀୖ᪼ࡍࡿࡢࡣࠊ࣑ࢪࣥࢥࡀ῝࠸ ࢔ࣘ࡬⧅ࡀࡿ㣗≀⥙࡜ྠࡌࡃࠊ2018 ᖺ 10 ᭶࡜ 2019 ᖺỈ῝ࡲ࡛⛣ືࡋࠊࡑࡇ࡛㣵ࢆ㣗࡭࡚࠸ࡿࡇ࡜ࢆ♧ࡋ࡚

10 ᭶ࡢ࣍ࣥࣔࣟࢥ࡬⧅ࡀࡿ㣗≀⥙ࡣࠊ<20 Pm ࡸ 20-45 Pm࠸ࡿࡢ࠿ࡶࡋࢀ࡞࠸㸦࣑ࢪࣥࢥࡀ㖄┤⛣ືࡋࡓ⤖ᯝ㸧ࠋࡢ୰ᑠᆺ⏕⏘⪅ࡀ㉳Ⅼ࡜࡞ࡗ࡚࠾ࡾࠊ45-250 Pm ࡢ኱ᆺ⏕ࡇࡢᵝ࡞⌮⏤ࡀ⪃࠼ࡽࢀࡿࡀࠊ᳨ドࡣ௒ᚋࡢㄢ㢟࡛࠶ࡿࠋ⏘⪅ࡣࡑࡢ㣗≀⥙࠿ࡽእࢀ࡚࠸ࡓ㸦ᅗ 3-4㸧ࠋࡇࡢ⤖ᯝࡣࠊ

ኟ࡟࣑ࢪࣥࢥࡢG15N ࡀୖ᪼ࡍࡿࡇ࡜ࢆᤊ࠼ࡓࡢࡣࠊᮏ◊࣑ࢡࣛࢫࢸࣜ࢔ࢫࡸࢫࢱ࢘ࣛࢫࢺ࣒ࣝࡢ኱Ⓨ⏕࡟ࡼࡾࠊ࣍

✲ࡀึࡵ࡚࡛࠶ࡿࠋࡑࡢ⌮⏤ࡣᮍゎ᫂ࡔࡀࠊG15N ࡀୖ᪼ࡍࣥࣔࣟࢥ࡬Ώࡿᰤ㣴⣲➼ࡶࠊῶᑡࡋ࡚࠸ࡿྍ⬟ᛶࡀ࠶ࡿࡇ

ࡿࡇ࡜࠿ࡽࠊኟ࡟࣑ࢪࣥࢥࡀ㣗࡭ࡿ㣵ࡢ㉁ࡀࠊ㏆ᖺ࡟ኚ໬࡜ࢆ♧ࡋ࡚࠸ࡿࠋࡇࡢྍ⬟ᛶࡶࠊ௒ᚋࠊ᳨ドࡍࡿᚲせࡀ࠶ࡿࠋ୍᪉ࠊᮏ◊✲ࡢ⤖ᯝ࠿ࡽࠊ࣍ࣥࣔࣟࢥࡢ㣵ࡢ 50㹼60%ࡋࡓ࡜⪃࠼ࡽࢀࡿࠋ

ࡣ࢝ࣈࢺ࣑ࢪࣥࢥ࡛࠶ࡾࠊ㣵ࡢ<30%ࡀ࣐ࣖࢺࣄࢤࢼ࢞ࢣ

 ࢣ࣑ࣥࢪࣥࢥ㢮ࡢ㣵࡟ࡘ࠸࡚ᮏ◊✲࡛࣐ࣖࢺࣄࢤࢼ࢞ࢣ࣑ࣥࢪࣥࢥ࡜ࢣ࣑ࣥࢪࣥࢥ
㢮ࡢG13C ࡜G15N ࢆㄪ࡭ࡓ⤖ᯝࠊG13C

ࡣ<20 Pm ࡸ 20-45 Pm࣑ࣥࢪࣥࢥ࡜ࢣ࣑ࣥࢪࣥࢥ㢮࡛࠶ࡿࡇ࡜ࡀศ࠿ࡗࡓࠋ⍇⍈†ࡢ࣍ࣥࣔࣟࢥࡢ㣗ᛶ࡟ࡘ࠸࡚ࡣࠊ࡯࡜ࢇ࡝▱ぢࡀ࡞࠸㸦༓ⴥࡽ 1987㸧ࠋࡼࡗ࡚ࠊᮏ◊✲ࡢ⤖ᯝࡣࠊ࣍ࣥࣔࣟࢥࡢ

ࡢ୰ᑠᆺ⏕⏘⪅ࡢ್࡟⃰⦰ಀᩘࢆ㊊ࡋࡓ⠊ᅖ࡟࡯࡜ࢇ࡝

㣗ᛶࢆ᫂ࡽ࠿࡟ࡋࡓ㈗㔜࡞▱ぢ࡜ゝ࠼ࡿࠋධࡗ࡚࠸ࡓࡢ࡟ᑐࡋࠊG15N ࡣྛࢧ࢖ࢬࡢ⏕⏘⪅࡟⃰⦰ಀᩘࢆ㊊ࡋࡓ⠊ᅖࡼࡾ㧗࠿ࡗࡓ㸦ᅗ 3-2㸧ࠋࡇࡢ⤖ᯝ࠿ࡽࠊ2 ࡲ࡜ࡵ

✀㢮ࡢࢣ࣑ࣥࢪࣥࢥࡣࠊ<20 Pm ࡸ 20-45 Pm ࡢ୰ᑠᆺ⏕⏘࢝ࣈࢺ࣑ࢪࣥࢥ࡜ࣉࣜ࢝ࣜ࢔ࡢG13C ࡜G15N ࢆㄪ࡭ࡓ⤖⪅ࢆ㉳Ⅼ࡜ࡍࡿ㣗≀⥙࡟ධࡗ࡚࠾ࡾࠊࡑࡢ⏕⏘⪅ࢆ㣵࡟ࡍ

ᯝࠊࡑࡢG13C ࡜G15N ࡣࠊ<20 Pm ࡸ 20-45 Pm ࡢ୰ᑠᆺ⏕ࡿఱ࠿ࡋࡽࡢ⏕≀ࢆ㣗࡭࡚࠸ࡓ࡜⪃࠼ࡽࢀࡿࠋᐇ㝿ࠊࡇࡢ⏘⪅ࡢ್࡟⃰⦰ಀᩘࢆ㊊ࡋࡓ⠊ᅖෆ࡟࡯࡜ࢇ࡝ධࡗ࡚࠾

2 ✀㢮ࡢࢣ࣑ࣥࢪࣥࢥࡣࠊ<20 Pm ࡢᑠᆺࡢ⏕⏘⪅ࢆ㣵࡟ࡾࠊ୰ᑠᆺࡢ⏕⏘⪅ࢆ㣗࡭࡚࠸ࡓ࡜⪃࠼ࡽࢀࡓࠋࡇࢀ࡟ᑐ

ࡍࡿ⧄ẟ⹸ࡸ࣒࣡ࢩ㢮ࢆ㣗࡭ࡿࡇ࡜ࡀ▱ࡽࢀ࡚࠸ࡿ

ࡋࠊ2 ✀ࡢ࣑ࢪࣥࢥࡢG13C ࡣࠊ45-250 Pm ࡢ኱ᆺ⏕⏘⪅ࡢ㸦Yamada et al., 1998㸹Yoshida et al., 2001㸧ࠋࡼࡗ࡚ࠊᮏ◊್࡟⃰⦰ಀᩘࢆ㊊ࡋࡓ⠊ᅖ࠿ࡽࡣእࢀ࡚࠾ࡾࠊ኱ᆺ⏕⏘⪅✲ࡢ⤖ᯝࡣࠊ㏆ᖺࡢ⍇⍈†࡟࠾࠸࡚ࡶࠊᙼࡽࡀࠊ<20 Pm ࡢࢆ࡯࡜ࢇ࡝㣗࡭࡞࠸࡜⪃࠼ࡽࢀࡓࠋ୍᪉ࠊኟ࡟ࡣࠊ࢝ࣈࢺ

⏕⏘⪅ࢆ㣵࡟ࡍࡿ⧄ẟ⹸ࡸ࣒࣡ࢩ㢮ࢆ㣗࡭࡚࠸ࡓࡇ࡜ࢆ

࣑ࢪࣥࢥ࡜ࣉࣜ࢝ࣜ࢔ࡢG15N ࡀࠊ୰ᑠᆺ⏕⏘⪅ࡢ್࡟⃰♧ࡋ࡚࠸ࡿ࡜⪃࠼ࡽࢀࡿࠋ

⦰ಀᩘࢆ㊊ࡋࡓ⠊ᅖࢆ㉸࠼ࡿࡇ࡜ࡀ࠶ࡗࡓࠋࡑࡢ⌮⏤ࡣᮍ ࢔ࣘࡸ࣍ࣥࣔࣟࢥ࡬⧅ࡀࡿ㣗≀⥙࡟ࡘ࠸࡚ 2018 ᖺ 7 ᭶࡜ 2019 ᖺ 7 ᭶࡛ࡣࠊ࢔ࣘ࡬⧅ࡀࡿ㣗≀⥙ࡣࠊ<20 Pm ࡸ 20-45 Pm ࡢ୰ᑠᆺ⏕⏘⪅ࡀ㉳Ⅼ࡜࡞ࡗ࡚࠸
ࡓ㸦ᅗ 3-3㸧ࠋࡲࡓࠊ࢔ࣘࡣࠊ࢝ࣈࢺ࣑ࢪࣥࢥ࡜ࣉࣜ࢝ࣜ࢔

ΠϤʤ੔‫ڗ‬ʥϙϱϠϫαʤ੔‫ڗ‬ʥ

༁50%ͥͯͲ
㕔Ͷ͵ͮͱ͏ΖΩϔφϝζϱαϕϨΩϨΠ Ωϔφϝζϱαࢆᖹᆒ⣙ 50%ࡎࡘࡢ๭ྜ࡛㣗࡭࡚࠸ࡓࠋ⍇⍈†ࡢ࢔ࣘࡀ࢝

ίϱϝζϱαથ໡ம౵ʃࣈࢺ࣑ࢪࣥࢥࢆ㑅ᢥⓗ࡟ᤕ㣗ࡍࡿࡇ࡜ࡣࠊKawabata et al.
㸦2006㸧➼ࡢ◊✲࡛▱ࡽࢀ࡚࠸ࡿࠋ୍᪉ࠊࣉࣜ࢝ࣜ࢔ࡣࠊ
1999 ᖺ࡟ึࡵ࡚⍇⍈†࡛ほᐹࡉࢀࡿࡼ࠺࡟࡞ࡗࡓ౵ධ✀࡛࠶ࡾ㸦Urabe et al., 2003㸧ࠊ࢔ࣘ➼ࡢᅾ᮶㨶࡜ࡢ㛵ಀࡣ◊✲ࡉࢀ࡚࠸࡞࠸ࠋࡼࡗ࡚ࠊᮏ◊✲ࡢ⤖ᯝࡣࠊ౵ධᚋ࡟⍇⍈†࡛ᐃ╔ࡋࡓࣉࣜ࢝ࣜ࢔ࡀࠊ࢔ࣘࡢ㣵࡟࡞ࡗ࡚࠸ࡿࡇ࡜ࢆ
♧ࡍ㈗㔜࡞᝟ሗ࡛࠶ࡿࠋ୍᪉ࠊᮏ◊✲ࡢ⤖ᯝ࠿ࡽࠊ45-250
Pm ࡢ኱ᆺ⏕⏘⪅ࡣࠊ࢔ࣘ࡬⧅ࡀࡿ㣗≀⥙࠿ࡽࡣእࢀࡓᏑ

<20Pm 20-45Pm 45-250 Pmਫ਼ࢊंਫ਼ࢊं ਫ਼ࢊं

<20Pm 20-45Pm 45-250 Pm
ਫ਼ࢊं ਫ਼ࢊं
ਫ਼ࢊंᅗ  G& ࡜G1 ࠿ࡽゎᯒࡋࡓ࢔ࣘ㸦ᕥ㸧ࡸ࣍ࣥࣔࣟࢥ㸦ྑ㸧࡬⧅ࡀࡿ㣗≀⥙ྛ㨶✀ࡢ㣵㑅ᢥᛶࡣࠊΰ
ྜࣔࢹ࡛ࣝ⟬ฟ  PP ⏕⏘⪅㸫⧄ẟ⹸➼㸫ࢣ࣑ࣥࢪࣥࢥࡢ⤒㊰ࡣG1 ࡸ᪤Ꮡ▱ぢࡼࡾ᥎ᐃ

⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮◊✲ሗ࿌᭩➨ 16 ྕ65ゎ᫂ࡔࡀࠊG15N ࡀୖ᪼ࡍࡿࡇ࡜࠿ࡽࠊኟ࡟ࡑࡢ 2 ✀ࡢ࣑ ᭷ᶵ≀཰ᨭ࡜㣗≀㐃㙐ࡢ≉ᚩࢪࣥࢥࡀ㣗࡭ࡿ㣵ࡢ㉁ࡀࠊ㏆ᖺ࡟ኚ໬ࡋࡓ࡜⪃࠼ࡽࢀࡓࠋ

†἟⏕ែ⣔ࡢ㣗≀㐃㙐࡟ࡣࠊ᳜≀ࣉࣛࣥࢡࢺࣥࢆື≀ࣉ

13C࣐ࣖࢺࣄࢤࢼ࢞ࢣ࣑ࣥࢪࣥࢥ࡜ࢣ࣑ࣥࢪࣥࢥ㢮ࡢ Gࣛࣥࢡࢺࣥࡀᤕ㣗ࡋࠊࡑࢀࢆ㨶㢮ࡀᤕ㣗ࡍࡿ⏕㣗㣗≀㐃㙐ࡣ<20 Pm ࡸ 20-45 Pm ࡢ୰ᑠࡔࡅ࡛࡞ࡃࠊ⣽⳦⩌㞟ࢆ㉳Ⅼ࡟⧄ẟ⹸ࡸ㠴ẟ⹸࡞࡝ࡢཎ⏕ᆺ⏕⏘⪅ࡢ್࡟⃰⦰ಀᩘࢆ㊊ࡋࡓ⠊ᅖ࡟࡯࡜ࢇ࡝ධࡗ࡚

ື≀ࡀ⣽⳦ࢆᤕ㣗ࡋࠊࡉࡽ࡟ື≀ࣉࣛࣥࢡࢺࣥࡢᤕ㣗࡬࡜࠸ࡓࡢ࡟ᑐࡋࠊG15N ࡣྛࢧ࢖ࢬࡢ⏕⏘⪅࡟⃰⦰ಀᩘࢆ㊊ࡘ࡞ࡀࡿᚤ⏕≀㣗≀㐃㙐ࡀᏑᅾࡍࡿ㸦ᅗ 㸧ࠋ㏆ᖺࡢ⍇ࡋࡓ⠊ᅖࡼࡾ㧗࠿ࡗࡓࠋࡇࡢ⤖ᯝ࠿ࡽࠊ2 ✀㢮ࡢࢣ࣑ࣥࢪ

⍈†ࡣᐩᰤ㣴໬ࡀᢚไࡉࢀࡘࡘ࠶ࡾࠊ᳜≀ࣉࣛࣥࢡࢺࣥ࡟

ࣥࢥࡣࠊ<20 Pm ࡢᑠᆺࡢ⏕⏘⪅ࢆ㣵࡟ࡍࡿ⧄ẟ⹸ࡸ࣒࣡ࡼࡿ୍ḟ⏕⏘㔞ࡸື≀ࣉࣛࣥࢡࢺࣥࡢῶᑡࠊࡉࡽ࡟㣵㈨※ࢩ㢮ࢆ㣗࡭࡚࠸ࡓ࡜⪃࠼ࡽࢀࡓࠋ

ࡢῶᑡ࡟ࡼࡾỈ⏘㈨※࡟ࡶᙳ㡪ࡢ࠶ࡿࡇ࡜ࡀᠱᛕࡉࢀ࡚

࡜G

15N ࢆㄪ࡭ࡓ⤖ᯝࠊG13C

ᮏ◊✲࡟ࡼࡿ࢔ࣘࡸ࣍ࣥࣔࣟࢥ࡬⧅ࡀࡿ㣗≀⥙ࡣࠊᅗ 3-࠸ࡿ㸦㓇஭ࡽࠊ㸧ࠋ㈋ᰤ㣴ୗࡢ㣗≀⥙࡛ࡣࠊ୍ḟ⏕⏘

5 ࡢࡼ࠺࡟࡞ࡗࡓࠋ࢔ࣘࡢሙྜࡣࠊ<20 Pm ࡸ 20-45 Pm ࡢࡢῶᑡ࡟ࡼࡗ࡚┦ᑐⓗ࡟ᚤ⏕≀㣗≀㐃㙐ࡢ㔜せᛶࡀቑࡍ୰ᑠᆺ⏕⏘⪅㸫࢝ࣈࢺ࣑ࢪࣥࢥࡸࣉࣜ࢝ࣜ࢔㸫࢔ࣘ࡜࠸࡜ࡢㄝࡀ࠶ࡾ ຍ⸨࣭ቑ⏣ࠊ ࠊᚤ⏕≀㣗≀㐃㙐࡟ࡼࡿࡗࡓ㣗≀⥙࡟࡞ࡗ࡚࠸ࡓࠋ୍᪉ࠊ࣍ࣥࣔࣟࢥࡢሙྜࡣࠊ<20†ෆࡢ≀㉁ᚠ⎔࡬ࡢᐤ୚ࡀὀ┠ࡉࢀࡓࠋࡑࡇ࡛ࠊ᳜≀ࣉࣛ

Pm ࡸ 20-45 Pm ࡢ୰ᑠᆺ⏕⏘⪅㸫࢝ࣈࢺ࣑ࢪࣥࢥࡸࢣࣥ

ࣥࢡࢺࣥࡸ⣽⳦ࡢ⏕⏘㔞➼ࢆ࣑ࢪࣥࢥ㸫࣍ࣥࣔࣟࢥ࡜࠸࠺㣗≀⥙࡟࡞ࡗ࡚࠸ࡓࠋ኱ᆺ⸴

࡜࡜ࡶ࡟ࠊྛ⏕≀ࡢ⏕⏘㔞࡜⌧Ꮡ㔞࠿ࡽ㛵ಀᛶࢆ⪃ᐹࡋࡓࠋᐃࡋ࡚ࢹ࣮ࢱࢆ⵳✚ࡍࡿ㢮࣑ࢡࣛࢫࢸࣜ࢔ࢫࡸࢫࢱ࢘ࣛࢫࢺ࣒ࣝࢆྵࡴ 45-250 Pmࡢ኱ᆺ⏕⏘⪅ࡣࠊ࠸ࡎࢀࡢ㣗≀⥙࠿ࡽࡶእࢀ࡚࠸ࡓࠋࡇࡢ
ࡇ࡜࠿ࡽࠊ኱Ⓨ⏕ࡋࡓ኱ᆺ⸴㢮ࡣࠊ୰ᑠᆺ⏕⏘⪅ࡢᰤ㣴ሷࢆዣ࠸ࠊ࢔ࣘࡸ࣍ࣥࣔࣟࢥ࡬Ώࡿࡣࡎ࡛࠶ࡗࡓᰤ㣴⣲➼ࡢ㔞ࢆῶࡽࡋ࡚࠸ࡿྍ⬟ᛶࡀ࠶ࡿ࡜⪃࠼ࡽࢀࡓࠋ
 ⍇⍈†࡟࠾ࡅࡿ᭷ᶵ≀཰ᨭࡢᢕᥱ
 ࡣࡌࡵ࡟
㹼 ᖺᗘ࡟⎔ቃ┬⎔ቃ◊✲⥲ྜ᥎㐍㈝ࡢຓᡂࢆཷ
ࡅ࡚ࠕ⍇⍈†࡟࠾ࡅࡿ᭷ᶵ≀཰ᨭࡢᢕᥱ࡟㛵ࡍࡿ◊✲ࠖ㸦௨ᅗ ⏕㣗㣗≀㐃㙐࡜ᚤ⏕≀㣗≀㐃㙐ࡢᴫᛕᅗ

ୗࠕ᥎㐍㈝◊✲ࠖ࡜࠸࠺ࠋ㸧ࢆᐇ᪋ࡋࡓࠋᮏ❶࡛ࡣࠊࡇࡢ

◊✲ࢆ୰ᚰ࡟ᚓࡽࢀࡓᡂᯝࡢᴫせࢆ⤂௓ࡍࡿࠋ◊✲ࡢヲ⣽‫ی‬⍇⍈†࡟࠾ࡅࡿ᳜≀ࣉࣛࣥࢡࢺࣥࠊື≀ࣉࣛࣥࢡࢺࣥࠊ

࡟ࡘ࠸࡚ࡣࠊ⊂❧⾜ᨻἲே⎔ቃಖ඲෌⏕ᶵᵓࡢ :HE ࢧ࢖ࢺ⣽⳦ࡢ⏕⏘ᛶ࡟㛵ࡋ࡚ࠊඛ㐍ࡢྛᐇἲࢆ☜❧ࡋࡓࠋྛᐇ

ୖ࡟⤊஢◊✲ᡂᯝሗ࿌᭩ࡀᥖ㍕ࡉࢀ࡚࠸ࡿࡢ࡛ࠊࡑࡕࡽࢆ

್࡟ࡶ࡜࡙ࡃ⍇⍈†Ἀᖏࡢ᭷ᶵⅣ⣲཰ᨭࢆᴫ⟬ࡍࡿ࡜ࠊཧ↷ࡋ࡚࠸ࡓࡔࡁࡓ࠸㸦⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ⣽⳦ࡀࡶࡘⅣ⣲せồ㔞㸦⥲⏕⏘ຊ㸧ࡣ୍ḟ⏕⏘㔞ࡢ⣙ 㸣࣮ࠊ㸧ࠋ࡟┦ᙜࡋ࡚࠸ࡓࠋࡋ࠿ࡋ⣽⳦ࡢ࿧྾ࢆᘬ࠸ࡓ⣽⳦⏕⏘㔞㸦⣧⏕⏘ຊ㸧ࡣᑠࡉࡃࠊᚤ⏕≀㣗≀㐃㙐ࡢୖ఩ࡢᤕ㣗⪅࡬ ᥎㐍㈝◊✲ࡢ୺࡞ᡂᯝ

ࡢ᭷ᶵ≀౪⤥ࡣஈࡋ࠸ࡇ࡜ࡀ᫂ࡽ࠿࡜࡞ࡗࡓࠋ

᥎㐍㈝◊✲ࡣࠊ௨ୗࡢࡼ࠺࡞㊃᪨࡛ᐇ᪋ࡋࡓࠋ

‫ی‬⣽⳦ࡸཎ⏕⏕≀ࡢᤕ㣗࡟ࡼࡿື≀ࣉࣛࣥࢡࢺࣥࡢᡂ㛗

Ỉ㉁ಖ඲࡜ᅾ᮶⏕≀⩌㞟ࡢᅇ᚟࡜࠸࠺୧⪅ࡢࣂࣛࣥࢫ

ࡸ⏕⏘ࢆホ౯ࡍࡿࡓࡵࠊᇵ㣴࣭㔝እᐇ㦂ࢆ⾜ࡗࡓ⤖ᯝࠊ౛ࢆ࡜ࡿࡓࡵࠊ†ෆࡢ᭷ᶵ≀㉁ࡢ཰ᨭࢆᢕᥱࡍࡿࡇ࡜ࡀ㔜せእࡣ࠶ࡿࡶࡢࡢࠊ⍇⍈†ࡢື≀ࣉࣛࣥࢡࢺࣥࡢ⏕⏘ᛶࡣࠊ࡛࠶ࡿࠋࡑࡇ࡛ࠊ⍇⍈†࡟࠾ࡅࡿ୍ḟ⏕⏘ࠊ⣽⳦⏕⏘ࠊື⣽⳦ࡸཎ⏕⏕≀ࡼࡾࡶ᳜≀ࣉࣛࣥࢡࢺࣥࡢᤕ㣗࡛㧗࠸ࡇ≀ࣉࣛࣥࢡࢺࣥࡢ⏕⏘࡟ࡘ࠸࡚࡜ࢆぢฟࡋࡓ㸦Ọ⏣ࡽࠊ㸧ࠋᐃࢆ⾜࠸ࠊỈᇦෆࡢ㣗≀㐃㙐࡟࠿࠿ࡿ≀㉁ᚠ⎔ࡢ≉ᛶࡸၥ㢟Ⅼࢆ᫂ࡽ࠿࡟ࡋࡓࠋࡉ

௨ୖࡢࡇ࡜࠿ࡽࠊ⍇⍈†ࡢ≀㉁ᚠ⎔ࡢ⌧≧ࡣࠊ㣗≀㐃㙐ࡽ࡟᭷ᶵⅣ⣲ࣇ࣮ࣟࡢᢕᥱ࠿ࡽࠊ†἟⎔ቃࡢ⌧≧࡟ྜࢃࡏ࡟࠾ࡅࡿ㧗ḟᤕ㣗⪅㸦㨶㢮➼㸧࡬ࡢ≀㉁ఏ㐩࡟ࡣࠊᚤ⏕≀ࡓⓗ☜࠿ࡘຠ⋡ⓗ࡞Ỉ㉁⟶⌮ࡸ⏕ែ⣔⟶⌮ࡀᐇ⌧࡛ࡁࡿ㣗≀㐃㙐ࡼࡾ⏕㣗㣗≀㐃㙐ࡀ୺య࡛࠶ࡿ࡜ุ᩿ࡉࢀࡓࠋࡑ

ࡼ࠺ࠊ†ࡢ⏕⏘ᛶࡢࡢࡓࡵࠊ㣵୙㊊ࢆゎᾘࡍࡿࡓࡵࡢ㨶㢮➼ࡢಖ඲࡟ࡣࠊື≀ᐃᡭἲࡸ⟶⌮ᣦᶆࢆ᳨ウࡋࡓࠋ

3 ᖺ㛫ࡢ◊✲࡛ᵝࠎ࡞▱ぢࡀᚓࡽࢀࡓࡢ࡛ࠊせⅬࢆ࠾ࡉࣉࣛࣥࢡࢺࣥࢆቑࡸࡍࡇ࡜ࠊࡉࡽ࡟ື≀ࣉࣛࣥࢡࢺࣥ࡟㣗࠼ࡘࡘ௨ୗ࡟グࡋࡓࠋ㸦‫ࡣی‬᥎㐍㈝◊✲࡛ᚓࡽࢀࡓ▱ぢ㸧࡭ࡽࢀࡸࡍ࠸ ȣP ௨ୗࡢࢧ࢖ࢬࡢ᳜≀ࣉࣛࣥࢡࢺࣥࢆ
ቑࡸࡍࡇ࡜ࡀ㔜せ࡜⪃࠼ࡽࢀࡓࠋ

66⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ヨ㦂◊✲ሗ࿌᭩➨ 16 ྕ ≀㉁ᚠ⎔ࡢࣇ࣮ࣟࢆ

ᐃࡍࡿ᪂ᡭἲ

ᶵ≀ࡢᐤ୚ᗘᐃ㔞ἲࢆࠊศᯒἲ㛤Ⓨ࡜ᚤ⏕≀ᇵ㣴ᐇ㦂࡟ࡼᐃࡍࡿࡓࡵࡢ᪂ᡭἲ

ࡾࠊ†἟⎔ቃ࡛ࡶ㐺⏝ྍ⬟࡞࢔ࣉ࣮ࣟࢳ࡜ࡋ࡚᪂ࡓ࡟☜❧ࢆ☜❧ࡋࡓࠋࡇࢀࡽࡢ᪂ᡭἲࡣࠊ†἟࡟࠾࠸࡚≀㉁ᚠ⎔ࢆࡋࡓࠋ⍇⍈††Ỉࡢ '࢔࣑ࣀ㓟ศᯒ࠿ࡽࠊ†Ỉ '20㸦⁐Ꮡᇶ♏࡜ࡋࡓỈ㉁⟶⌮ࢆ⾜࠺ୖ࡛᭷⏝࡛࠶ࡿࠋ௨ୗ࡟ࡑࡢ᪂

᭷ᶵ≀㸧ࡢ⏕ᡂ※࡜ࡋ࡚⣽⳦ࡢᐤ୚ࡀ㔜せ࡛࠶ࡿࡇ࡜ࡀศ

ᡭἲ࡜ࡑࡢᡂᯝࢆิグࡋࡓࠋ࠿ࡗࡓࠋ≉࡟㞴ศゎᛶ '20 ࡟ࡣࠊ⣽⳦ࡀ ⛬ᗘᐤ୚‫ࢫࣝࣃی‬ኚㄪᘧࢡࣟࣟࣇ࢕ࣝບ㉳⺯ගἲ࡞࡝ࡢගᏛⓗᡭࡋ࡚࠸ࡓࠋࡘࡲࡾࠊ†Ỉ '20 ࡟ࡣࠊ⣽⳦࠾ࡼࡧ᳜≀ࣉࣛࣥἲࢆ⤌ࡳྜࢃࡏ࡚ࠊ㐃⥆ࡢ୍ḟ⏕⏘㏿ᗘࡢࢡࢺࣥ➼ࡢࠊᑡ࡞ࡃ࡜ࡶ஧✀㢮ࡢ␗࡞ࡿ⏕ᡂ※ࡀᏑᅾࡋࡓࠋ
ᮏ◊✲࡛ࡣࠊ≀㉁ᚠ⎔ࡢࣇ࣮ࣟࢆ

ᐃἲࢆ☜❧ࡋࠊ

Ꮨ⠇ኚືࡸẼ㇟࢖࣋ࣥࢺ࡟ᛂ⟅ࡍࡿ኱ᆺ⥳⸴࡞࡝ࡢ᳜≀‫ی‬᭷ᶵ≀ࡢ⏕ศゎᛶࢆホ౯ࡍࡿศᯒᡭἲ࡜ࡋ࡚ %2'㸦⏕≀ࣉࣛࣥࢡࢺࣥࡢ୍ḟ⏕⏘㏿ᗘࡢኚ໬ࢆほ໬Ꮫⓗ㓟⣲せồ㔞㸧ࡀ࠶ࡿࡀࠊ⍇⍈†࡟࠾࠸࡚ࡣᚑ᮶ࡢ ࡣᚑ᮶ࡢ࡛ࡁࡓࠋࡇࢀࡽ

ᐃἲ࡛ࡣᤊ࠼ࡿࡇ࡜ࡀ࡛ࡁ࡞࠿ࡗࡓ⌧㇟࡛ࠊ⍇᪥㛫ࡢᇵ㣴ᮇ㛫㸦%2'㸧࡛ࡣᐃୗ㝈್࡛࠶ࡿ PJ/ ᮍ⍈†࡟࠾ࡅࡿỈ㉁ࡸ୍ḟ⏕⏘ࢆ⪃࠼ࡿୖ࡛᭷⏝࡞▱ぢ࡜‶࡜࡞ࡿࡇ࡜ࡀ㢖Ⓨࡋࠊ⢭ᗘ࡟ၥ㢟ࡀ࠶ࡗࡓࠋࡑࡇ࡛ᇵ㣴࡞ࡗࡓ㸦ᅗ 㸧ࠋᮇ㛫ࢆ  ᪥㛫㸦%2'㸧࡟ᘏ㛗ࡍࡿࡇ࡜࡟ࡼࡾࠊ㓟⣲ᾘ㈝㔞ࡀ⣙  ಸ࡜࡞ࡾࠊከࡃࡢヨᩱ࡛ᗘࡼࡃᐃୗ㝈್ࢆୖᅇࡾࠊ⢭ᐃࡍࡿࡇ࡜ࡀ࡛ࡁࡓ㸦ᅗ 㸧ࠋ%2' ࡜ %2' ࡢẚ⋡ࡢኚືࡣࠊỈ୰ࡢ᭷ᶵ≀ࡀ኱ࡁࡃኚ໬ࡍࡿ᳜≀ࣉࣛࣥࢡࢺࣥࡢቑṪ࡜㛵ಀ࡞ࡃࠊ%2' ࡀ  PJ/ ௨ୗ࡛ࡤࡽࡘࡁ
ࡀ኱ࡁࡃ࡞ࡗࡓࠋࡇࡢࡇ࡜ࡣࠊ%2' ࡀ  PJ/ ௨ୗ࡛ࡣ⢭ᗘࢆ☜ಖ࡛ࡁ࡚࠸࡞࠸ࡇ࡜ࢆ♧၀ࡋࡓ㸦ᅗ 㸧ࠋᐃἲ㸦࢖࣓࣮ࢪ㸧ᅗ ୍ḟ⏕⏘ࡢගᏛⓗ‫ی‬⣽⳦ࡢ⏕⏘㔞ᐃἲ࡟ࡘ࠸࡚ࠊ1ࢹ࢜࢟ࢩ࢔ࢹࣀࢩࣥ

ἲࢆ⏝࠸ࡓ⣽⳦⏕⏘ࡢᐃ㔞ࡀ☜❧ࡋࠊࡇࢀࡲ࡛࡟⌧ሙ࡛ࡢᐃࡀᅔ㞴࡛࠶ࡗࡓ⣽⳦⏕⏘࡟㛵ࡋ࡚ࠊᅜෆ࡟㢮ࢆぢ࡞࠸
ከᆅⅬࠊከ㢖ᗘࡢ⣽⳦⏕⏘ᐃࢆ⾜࠼ࡿࡼ࠺࡟࡞ࡗࡓ㸦ᅗ㸧ࠋࡑࡢ⤖ᯝࠊࡇࢀࡲ࡛▱ࡽࢀ࡚࠸࡞࠿ࡗࡓ⍇⍈†ෆࡢᆅⅬ㛫ࡸ῝ࡉ᪉ྥࡢ⣽⳦άᛶࡢ㐪࠸ࠊ㛗ᮇⓗ࡞⍇⍈†ࡢ⣽⳦⏕⏘ࡢῶᑡࢆ᫂ࡽ࠿࡟ࡋࡓ㸦7VXFKL\DHWDO㸧ࠋᅗ  ໭†௒ὠἈ୰ኸ࡟࠾ࡅࡿ %2' ࡜ %2'ࠊ࠾ࡼࡧ
%2'%2' ẚࡢ⤒᭶ኚື ᭷ᶵ≀ᣦᶆࡢᩚ⌮Ỉ㉁ᨵၿࡢ㐍ࡴ†἟࡟࠾࠸࡚ࡶ⏕ែ⣔ࡢᨩ஘ࡀ⥆࠸࡚࠾ࡾࠊබඹ⏝Ỉᇦࡢ⎔ቃಖ඲࡟ࡣࠊ⏕ែ⣔ಖ඲ࢆྵࡵࡓ᪂
ࡓ࡞Ỉ㉁⟶⌮ࡢᯟ⤌ࡳࢆᵓ⠏ࡍࡿᚲせࡀ࠶ࡿࠋ†἟࡟࠾ࡅࡿ⏕ែ⣔ࡢ≧ែࢆᢕᥱࡍࡿ㸯ࡘࡢ᪉⟇࡟ࡣࠊ⏕ែ⣔ࢆ௓ࡋࡓᰤ㣴⣲ࡸ᭷ᶵ≀ࡢࢿࢵࢺ࣮࣡ࢡ࡜࢚ࢿࣝࢠ࣮ࡢࣇࣛࢵ
ࢡࢫࢆゎᯒࡍࡿࡇ࡜࡛࠶ࡿ 5H\MROHWDO ࠋ౛࠼ᅗ ⣽⳦⏕⏘㔞ࡢᐃἲ㸦࢖࣓࣮ࢪ㸧‫ی‬⣽⳦࡜ཎ⏕⏕≀ࡢ⌧Ꮡ㔞࡜✀࣭ࢢ࣮ࣝࣉ࡛ࣞ࣋ࣝࡢ⩌㞟⤌ᡂࢆ࣓ࢱࢤࣀ࣑ࢡࢫゎᯒ࡟ࡼࡗ࡚✵㛫࣭Ꮨ⠇ⓗ࡟ヲ⣽࡟᫂ࡽ࠿࡟ࡋ࡚ࠊ᪂つᮍᇵ㣴⣽⳦ࡢ୍኱⣔⤫⩌ࢆྵࡴ⍇⍈†ࡢ⣽⳦⩌㞟ࡢከᵝᛶࡢ㧗ࡉࢆぢฟࡋࡓ㸦2ND]DNLHWDO0XNKHUMHHHWDO㸧ࠋ‫ࣀ࣑࢔'ی‬㓟ࣂ࢖࣐࣮࣮࢜࢝ࢆ⏝࠸ࡓࠊ⣽⳦⏤᮶ࡢ⁐Ꮡ᭷ࡤࠊ⏕ែ⣔࡟࠾ࡅࡿ㣗≀⥙ࡢᢕᥱ࡟ࡣࠊྛᰤ㣴ẁ㝵࡟࠾ࡅࡿ࢚ࢿࣝࢠ࣮ࡸᰤ㣴ඖ⣲㸦❅⣲ࠊࣜࣥ㸧ࡢຠ⋡ࡀ㆟ㄽࡉࢀࡿࠋ୍᪉࡛ࠊỈ㉁ಖ඲࡟ࡶỈ୰ࡢ❅⣲ࡸࣜࣥ࡞࡝ࡢᰤ㣴ሷ㢮࡜᭷ᶵ≀ࡢไᚚࡀồࡵࡽࢀࡿࠋ୧⪅࡟࠾࠸࡚ᰤ㣴ඖ⣲ࡸ᭷ᶵ≀ࡣඹ㏻ࡍࡿࡇ࡜࠿ࡽࠊ†἟࡟࠾ࡅࡿᰤ㣴࣭᭷ᶵ≀ࡢࣇࣛࢵࢡࢫࠊࡍ࡞ࢃࡕ≀㉁ᚠ⎔ࡢゎᯒࡀ᪂ࡓ࡞Ỉ㉁⟶⌮ᡭἲ࡬ࡢ᭷ຠ࡞ᡭẁ࡜࡞ࡿࡇ࡜ࡀᮇᚅࡉࢀࡿࠋࡑࡢ➨୍Ṍ࡜ࡋ࡚ࠊ᭷ᶵ≀㔞ࢆ♧ࡍ᭷ᶵⅣ⣲ࡢ⌧Ꮡ㔞㸦ࢫࢺࢵࢡ㸧࡜⛣ὶ㔞㸦ࣇ࣮ࣟ㸧ࢆྍど໬ࡋࡓ⎔ቃホ౯ࡢά⏝ࡀ࠶ࡆࡽࢀࡿࠋ

⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮◊✲ሗ࿌᭩➨ 16 ྕ

67†἟࡟࠾ࡅࡿ᭷ᶵở⃮ࡢᣦᶆ࡟ࡣ &2'㸦໬Ꮫⓗ㓟⣲せồ࡟ࡼࡿᐃ࡛ࡣࠊ㉸㡢Ἴ࣍ࣔࢪࢼ࢖ࢬ࡟ࡼࡗ࡚ᠱ⃮≀ࢆ◚㔞㸧ࡀ⏝࠸ࡽࢀ࡚ࡁࡓࡀࠊ඲᭷ᶵⅣ⣲㸦72&㸧ࢆ⏝࠸ࡿ᭷○ࡍࡿࡇ࡜࡛㸪ศᩓࡋࡓ≀㉁ࡢᆒ㉁໬ࢆಁࡋ㸪72&⏝ᛶࡀぢ࠼࡟ࡃ࠿ࡗࡓࠋࡑࡇ࡛ᮏ◊✲࡛ࡣࠊ㐣ཤ࡟⍇⍈†ࡢ☜ᗘࢆྥୖ࡛ࡁࡿࠋࡲࡓࠊヨᩱࡢὀධࢩࣜࣥࢪෆࡸᶵჾ

ὶᇦ࡛ㄪᰝࡉࢀࡓ &2' ࡜ 72& ࢹ࣮ࢱ࡟ࡘ࠸࡚㛵ಀࢆᩚ⌮ෆࡢ⤒㊰ࡢῶኻࢆᑡ࡞ࡃタィࡉࢀࡓ 72& ィࢆ⏝࠸ࡿࠊ72&ࡋࡓ㸦᪩ᕝࡽࠊ㸧
ࠋ&2' ࡣࠊ72& ࡜┦㛵ࡀ࠶ࡾࠊ┦ᑐⓗ⇞↝㓟໬᪉ᘧ࡟࠶ࡿ 132& ἲ࡜ 7&,& ἲࡢ㸰ࡘࡢ࡟᭷ᶵở⃮ࡢࣞ࣋ࣝࢆ♧ࡍᣦᶆ࡜ࡋ࡚ࡣ᭷ຠ࡛࠶ࡗࡓࠋࡋ

ࢆヨᩱ⃰ᗘ࡟ࡼࡗ࡚౑࠸ศࡅࡿࠊ࡞࡝࡟ࡼࡾ

࠿ࡋࠊ⏕ศゎ᫬ࡢ㓟⣲ᾘ㈝㔞࡜ &2' ࡣ➼㔞࡛ࡣ࡞࠸ࡇ࡜

ୖࡍࡿ㸦᪩ᕝࡽࠊ㸧ࠋ

ᐃ್

ᐃ᪉ἲ

ᐃ⢭ᗘࡀྥ

ࡸࠊヨᩱࡢ⃰ᗘࡸ㉁㸦ᠱ⃮≀㸧ࡢ㐪࠸࡟ࡼࡾ &2' ࡟ᕪࡀฟ௨ୖࡢࡇ࡜࠿ࡽࠊබඹ⏝Ỉᇦࡢ⏕ែ⣔ಖ඲࡜ࡢ୧❧ࢆ┠ࡿࡇ࡜ࡀ☜ㄆࡉࢀࡓ㸦ᅗ 㸧ࠋ౛࠼ࡤࠊᠱ⃮⢏Ꮚࢆྵࡴ†ᣦࡍ᪂ࡓ࡞Ỉ㉁⟶⌮ࡢᯟ⤌ࡳ࡟ࡣࠊỈ㉁ࡔࡅ࡛࡞ࡃ⏕≀㔞Ỉࡢ &2'

ᐃ್ࡀప࠸ࡇ࡜࠿ࡽࠊ

ࡢᣦᶆ࡟ࡶ࡞ࡿ᭷ᶵⅣ⣲ࡀᚠ⎔ࢆぢࡿ≀ᕪ࡜ࡋ࡚ά⏝ࢆᐃ࡛ࡣ㓟໬ຠ⋡ࡀపୗࡋ࡚㐣ᑡホ౯ᮇᚅ࡛ࡁࡿࠋ⥲ᣓⓗ࡞◊✲ࡢᴫせࢆ࣏ࣥࢳ⤮㸦ᅗ 㸧࡟

ᐃ࡛ࡣࠊ72& ࡟ẚ࡭࡚⢏Ꮚࢆྵࡴ &2' ࡢ࡟࡞ࡿ㸦ᅗ 㸧ࠋ௨ୖࡢࡇ࡜࠿ࡽࠊỈ⎔ቃࡢ᭷ᶵ≀㔞ࢆṇࡲ࡜ࡵࡓࠋ

☜࡟♧ࡍ࡟ࡣ 72& ࢆ⏝࠸ࡿ࡭ࡁ࡛࠶ࡿࠋ

 ⎔ቃ⾜ᨻ࡬ࡢᥦ᱌
ࡲࡓࠊࡇࡢ⎔ቃ◊✲⥲ྜ᥎㐍㈝ࡢ◊✲࡛ࡣࠊᚓࡽࢀࡓ◊✲ᡂᯝࢆ⎔ቃ┬➼ࡢ⾜ᨻࡀ⾜࠺ᨻ⟇❧᱌࡟ࡘ࡞ࡆࡿࡓࡵ
࡟ࠕᨻ⟇Ỵᐃ⪅ྥࡅࢧ࣐࣮ࣜࠖࢆసᡂࡋ࡚ᥦฟࡋࡓࠋࢧ࣐
࣮ࣜࡣ :HE ࢧ࢖ࢺୖ࡛බ㛤ࡉࢀ࡚࠸࡞࠸ࡓࡵࠊ௨ୗ࡟ࡑࡢ
ᥦ᱌ࢆ⤂௓ࡍࡿࠋ
࠙බඹ⏝Ỉᇦ࡟࠾ࡅࡿ᭷ᶵⅣ⣲ࡢィᅗ  †Ỉ࡜ὶᇦἙᕝỈ࡟࠾ࡅࡿᠱ⃮ែ࡜⁐Ꮡែ࡟ศࡅ
ࡓ &2' ࡜ 72& ࡢ㛵ಀᛶ㸬ࡑࡢ 72& ࡶࠊ⇞↝㓟໬ᘧ 72& ィ࡟ࡼࡿᠱ⃮≀ࢆྵࡴヨᩱࡢᐃ࡛ࡣࠊṇ☜ᛶࡀⴠࡕࡿࡇ࡜ࡀ࠶ࡿࡓࡵࠊ ᐃ᪉ἲࡢᨵၿᡭἲࡶᥦ᱌ࡋࡓ㸦᪩ᕝࡽࠊ㸧ࠋ⇞↝㓟໬ᘧ 72& ィ࡟ࡘ࠸࡚ࠚ

Ỉ㉁ᨵၿࡢ㐍ࡴ†἟࡟࠾࠸࡚ࡶ⏕ែ⣔ࡢᨩ஘ࡀ⥆࠸࡚࠾ࡾࠊබඹ⏝Ỉᇦࡢ⎔ቃಖ඲࡟ࡣࠊ⏕ែ⣔ಖ඲ࢆど㔝࡟ධࢀࡓ᪂ࡓ࡞Ỉ㉁⟶⌮ࡢᯟ⤌ࡳࢆᵓ⠏ࡍࡿᚲせࡀ࠶ࡿࠋࡑࡢ
ࡓࡵ࡟ࡣࠊỈ㉁ࡔࡅ࡛࡞ࡃ⏕≀㔞ࡢᣦᶆ࡟ࡶ࡞ࡿ᭷ᶵⅣ⣲ࡢィ ࢆ⌧≧ࡢ &2' ࡟ࡼࡿỈ㉁ࣔࢽࢱࣜࣥࢢ࡟ే⏝ࡋ࡚ጞࡵࡿ࡭ࡁ࡛࠶ࡿࠋ
ᅗ  ࠕ⍇⍈†࡟࠾ࡅࡿ᭷ᶵ≀཰ᨭࡢᢕᥱ࡟㛵ࡍࡿ◊✲ࠖࡢ࣏ࣥࢳ⤮㸬⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ ࢆᨵゞ

68⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ヨ㦂◊✲ሗ࿌᭩➨ 16 ྕ࠙㨶㢮ࡢቑຍࢆ┠ⓗ࡜ࡋࡓᰤ㣴ሷࡢ㈇Ⲵ࡟ࡘ࠸࡚ࠚ㸦㔠ࡽ, 2018㸧ࠋࡋ࠿ࡋࠊ㞴ศゎᛶ᭷ᶵ≀࡜᫆ศゎᛶ᭷ᶵ≀†἟࡟࠾࠸࡚㨶㢮ࡢቑຍࢆ┠ⓗ࡜ࡋࡓᰤ㣴ሷࡢ㈇Ⲵቑ࣭

ࡑࢀࡒࢀࡢ㉳※ࡸࠊ᭷ᶵ≀ࡢ㞴ศゎ/᫆ศゎẚ⋡ࡀ᫬✵㛫ῧຍࡣࠊ᳜≀ࣉࣛࣥࢡࢺࣥࡢቑຍ࡟ࡣࡘ࡞ࡀࡿࡶࡢࡢࠊࡑ

ⓗ࡟ኚ໬ࡍࡿ࣓࢝ࢽࢬ࣒࡟ࡘ࠸࡚ࡣࠊ୙᫂Ⅼࡀࡲࡔᩘከࡃ

ࢀ࡟ẚࡋࡓ㨶㢮ࡢቑຍࡀ࡞࠸ࠊ࠶ࡿ࠸ࡣቑຍᑐ㇟࡛࡞࠸㨶ṧࡉࢀ࡚࠸ࡓࠋ

✀ࡀቑ࠼ࡿ࡞࡝ࠊᮃࡲ࡞࠸⤖ᯝࢆࡶࡓࡽࡍྍ⬟ᛶࡀ࠶ࡿࡇ

୍ࡘ┠ࡢ኱ࡁ࡞ㄢ㢟࡜ࡋ࡚ࠊ᭷ᶵ≀ࡢ㉳※᥎ᐃࡢᡭἲ࡟
୙☜ᐃᛶࡀṧࡗ࡚࠸ࡿࠋ⍇⍈†໭†࡛ࡣࠊ†Ỉ DOC ࡢ δ13C

࡜࡟␃ពࡍ࡭ࡁ࡛࠶ࡿࠋ
ᐃ࡟ࡘ࠸࡚ࠚ್ࡢỈ῝ู࣭Ꮨ⠇ูศᕸ࡜ࠊὶධἙᕝỈ DOC ࡢ δ13C ್ࡀ᳜≀ࣉࣛࣥࢡࢺࣥࡢ୍ḟ⏕⏘㏿ᗘ࡜⌧Ꮡ㔞➼࡟㛵ࡍࡿሗ࿌ࡉࢀ࡚࠾ࡾࠊ⾲ᒙ†Ỉࡢ᫆ศゎᛶ DOC㸦LDOC㸧ࡣࠊ࠙බඹ⏝Ỉᇦࣔࢽࢱࣜࣥࢢ࡟࠾ࡅࡿගᏛⓗගᏛⓗᐃἲࡣࠊ†἟ࡸ㛢㙐ᛶᾏᇦ࡟࠾ࡅࡿ᳜≀ࣉࣛࣥࢡ୺࡟†ෆ⏕⏘⏤᮶࡜᥎ᐃࡉࢀ࡚࠸ࡿ㸦Maki et al., 2010㸧ࠋࢺࣥ⩌㞟ືែࡢࣔࢽࢱࣜࣥࢢ࡟ά⏝࡛ࡁࡿࠋ୍ḟ⏕⏘㔞ࡣࠊ୍᪉࡛ࠊ㞴ศゎᛶ DOC㸦RDOC㸧ࡢ୺せ㉳※࡜ࡋ࡚ࠊ†ෆỈᇦࡢ೺඲ᛶࢆ⪃࠼ࡿୖ࡛ࡶ㔜せ࡞せ⣲࡛࠶ࡿࡇ࡜࠿ࡽࠊ

⏕⏘⏤᮶࡜㝣ᇦ⏤᮶࡟ࡘ࠸࡚ࠊδ13C ್࠿ࡽࡣ༊ูࡀ㞴ࡋ࠸௒ᚋࠊỈ㉁⟶⌮࡜Ỉ⏘㈨※⟶⌮ࡢࡑࢀࡒࢀࡢ㒊ᒁ࡟࠾࠸࡚ࠊ

࡜ࡉࢀ࡚ࡁࡓࠋࡑࡢࡓࡵ Maki et al. (2010)ࡶࠊ௬ᐃ࡜ࡋ࡚ࠊ

ᮏᢏ⾡ࡢά⏝࡟ࡘ࠸᳨࡚ウࢆ㐍ࡵࡿ࡭ࡁ࡛࠶ࡿࠋ

ኳ↛ࡢỈ୰ DOC㸦῝Ỉᒙ†ỈࡸἙᕝỈ㸧ࡢ್ࢆࠊ†Ỉ୰࠙†἟ࡢ᪂ࡓ࡞Ỉ㉁⟶⌮ࡢ࠶ࡾ᪉࡟ࡘ࠸࡚ࠚ

࠾ࡼࡧ㝣ᇦ⏤᮶ RDOC ࡢ௦⾲࡜ࡋ࡚⏝࠸࡚࠸ࡿࠋࡘࡲࡾࠊ

Ỉᇦࡢ⥲ྜⓗ࡞どⅬ࡟ᇶ࡙ࡃຠᯝⓗ࡞Ỉ⎔ቃಖ඲᪋⟇RDOC ࡢ δ13C ್ࡣ┤᥋ᐃࡉࢀ࡚࠾ࡽࡎࠊDOC ㉳※᥎ᐃࢆ㐍ࡵࡿࡓࡵ࡟ࠊ᭷ᶵⅣ⣲࡟ࡼࡿ⌧Ꮡ㔞㸦ࢫࢺࢵࢡ㸧࡜⛣࡟ࡣ୙☜ᐃᛶࡀṧࡗ࡚࠸ࡓࠋ➨ᅄᮇ࡛ࡣࠊ2014 ᖺ 11 ᭶㹼ὶ㔞㸦ࣇ࣮ࣟ㸧ࢆྍど໬ࡋࡓ⎔ቃホ౯ࡢά⏝ࢆᥦ᱌ࡍࡿࠋ

2016 ᖺ 2 ᭶ࡢ⍇⍈†ࡢᵝࠎ࡞ᆅⅬࡢ†Ỉ࡟ࡘ࠸࡚ࠊ100 ᪥≉࡟Ỉ㉁ಖ඲࡜⏕ែ⣔ಖ඲ࡢ୧❧ࡢࡓࡵ࡟ࡣࠊᇶ♏⏕⏘ࡢ⏕ศゎヨ㦂࠿ࡽࠊRDOC ࡜ LDOC ࡑࢀࡒࢀࡢ δ13C ್ࢆሗ࠺ࡕᰤ㣴ẁ㝵ࡀୖ఩ࡢ⏕≀㸦ື≀ࣉࣛࣥࢡࢺࣥࠊ㨶㢮➼㸧࿌ࡋࡓ㸦㔠ࡽ, 2018㸧
ࠋ†Ỉ RDOC ࡢ δ13C ್ࡣ-26 ‰๓ᚋ࡟ᅇࡿ๭ྜ㸦㌿᥮ຠ⋡㸧ࢆቑࡸࡍࡇ࡜ࡀ㔜せ࡛࠶ࡿࡇ࡜࠿

࡜࡞ࡾࠊMaki et al. (2010)࡟ࡼࡿ⍇⍈†໭†ࡢ᥎ᐃ್࡜㏆ࡽࠊ௒ᚋࢫࢺࢵࢡ࡜ࣇ࣮ࣟࢆ⪃៖ࡋࡓ⎔ቃホ౯ࡢᐇ⏝໬࡟࠸ഴྥࡀᚓࡽࢀࡓࠋࡋ࠿ࡋ⍇⍈†࡛ࡣ㏆ᖺࠊ2016 ᖺ࡟኱ྥࡅ࡚ࠊ୍ḟ⏕⏘➼ࡢᆺ⥳⸴࣑ࢡࣛࢫࢸࣜ࢔ࢫ࣭ࣁ࣮ࢹ࢕ࡢࣈ࣮࣒ࣝࡀ㉳ࡁࡿ࡞ᐃࡢᑟධࡸ⏕ែ⣔ࣔࢹࣝࢆ⏝࠸ࡓ཰ᨭ᥎ᐃࡢ฼⏝࡞࡝ࢆ᳨ウࡍ࡭ࡁ࡛࠶ࡿࠋ

࡝ࠊ†ෆࡢ≀㉁ᚠ⎔࣭⏕ែ⣔࡟ኚ໬ࡀࡳࡽࢀ࡚࠾ࡾࠊ᭷ᶵ

⍇⍈†࡟࠾ࡅࡿ➨  ḟ†἟Ỉ㉁ಖ඲ィ⏬࡛ࡣࠊࡍ࡛࡟

≀ࡢືែࢆࡉࡽ࡟ㄪ࡭ࡿᚲせࡀ⏕ࡌ࡚ࡁࡓࠋࡲࡓࠊ➨ᅄᮇ72& ࢆᣦᶆ࡜ࡋ࡚ά⏝ࡉࢀ࡚࠸ࡿࠋࡇࢀ௨እ࡟ࡶᮏࢧ࣐࡛ࣜࡣࠊすࡢ†ࡢ†Ỉ࡟ࡘ࠸࡚ࡶྠᵝ࡟⏕ศゎヨ㦂ࢆ⾜࠸ࠊ࣮ࡀỈ⎔ቃࡢᨻ⟇❧᱌᳨ウࡢཧ⪃࡜࡞ࡾࠊࡉࡽ࡞ࡿ⎔ቃᨻ㝣ᇦ⏤᮶ RDOC ࡢ್ࢆ᥎⟇ࡸ◊✲࡬ࡢⓎᒎ࡟ࡘ࡞ࡀࡿࡇ࡜ࢆᮇᚅࡍࡿࠋࡢ್ࢆすࡢ††Ỉ DOC ࡀ௦⾲࡛ࡁࡿ࠿࡝࠺࠿ࡣ୙᫂ࡔࡗ

ࡋࡓࠋࡋ࠿ࡋࠊ
ὶධἙᕝỈ DOCࡓࠋ ≀㉁ᚠ⎔ࡢ≧ἣᢕᥱᡭἲ

஧ࡘ┠ࡢㄢ㢟࡜ࡋ࡚ࠊ᭷ᶵ≀ࡢ㞴ศゎ/᫆ศゎẚ⋡࡟ࡘ࠸࡚ࠊ㧗ゎീᗘ࡞᫬✵㛫ศᕸࡢᢕᥱࡸࠊࡑࡢኚື࣓࢝ࢽࢬ

 ࡣࡌࡵ࡟

࣒ゎ᫂࡟ྥࡅ࡚ࡣࠊᚑ᮶ἲ㸦100 ᪥⏕ศゎヨ㦂㸧ࡼࡾࡶ㎿ ⍇⍈†ࡢ†Ỉ୰ࡢ᭷ᶵ≀ࡣࠊ⏕ศゎᛶࡢప࠸㞴ศゎᛶ᭷

㏿࡞ᢕᥱᡭἲࡀᚲせ࡜࡞ࡗ࡚࠸ࡿࠋDOC ࡟ࡘ࠸࡚ࡣࠊศ

ᶵ≀࡜ࠊᩘ༑᪥ࢫࢣ࣮࡛ࣝ⏕ศゎࡉࢀࡿ‽᫆ศゎᛶ᭷ᶵ≀Ꮚࢧ࢖ࢬศᕸࡀ⏕ศゎᛶࡢᣦᶆ࡟࡞ࡿྍ⬟ᛶࡀ࠶ࡿࠋࡇࢀ

ࡀ࡯࡜ࢇ࡝ࢆ༨ࡵࡿࠋࡇࡢ࠺ࡕ㞴ศゎᛶ᭷ᶵ≀ࡣࠊ᭷ᶵở

ࡲ࡛ᵝࠎ࡞Ỉᅪ⎔ቃ࡟࠾࠸࡚ࠊDOC ࡢศᏊࢧ࢖ࢬ࡜⏕ศ⃮ࡢ⎔ቃᇶ‽࡛࠶ࡿ COD ࡢቑຍࡸࠊίỈ㐣⛬࡛ࡢࢺࣜࣁ

ゎᛶࡀ㛵㐃ࡍࡿഴྥࡀሗ࿌ࡉࢀࠊࠕࢧ࢖ࢬ཯ᛂᛶ㐃⥆య࣓ࣔࣟࢱࣥ⏕ᡂ⬟ࡢቑຍࡢཎᅉ࡜࡞ࡾ࠺ࡿࠋ୍᪉ࠊ᫆ศゎᛶࢹࣝࠖ㸦size-reactivity continuum model㸸ẚ㍑ⓗ᫆ศゎ࡞㧗᭷ᶵ≀ࡣࠊ⏕ศゎࡉࢀࡿ㐣⛬࡛ࠊỈ୰ࡢ⣽⳦௦ㅰࡢⅣ⣲※࣭ศᏊ DOC ࡀศゎࢆཷࡅ࡚ࠊ㞴ศゎ࡞పศᏊ DOC ࡟ᚎࠎ࢚ࢿࣝࢠ࣮※࡜࡞ࡿ࡯࠿ࠊ↓ᶵ໬ࡉࢀ࡚ᰤ㣴ሷࢆᨺฟࡍࡿ

࡟ኚ᥮ࡉࢀ࡚࠸ࡃ࡜ࡍࡿࣔࢹࣝ㸧ࡀᥦၐࡉࢀ࡚࠸ࡿ㸦Amon

ࡇ࡜࡛ࠊ†ෆࡢ≀㉁ᚠ⎔࡜⏕ែ⣔࡟㔜せ࡞ᙺ๭ࢆᯝࡓࡋ࡚

& Benner, 1996; Benner & Amon, 2015㸧ࠋࡋ࠿ࡋᚑ᮶ࠊኳ↛࠸ࡿ㸦Kim et al., 2006㸧ࠋࣞ࣋ࣝ⃰ᗘࡢỈᅪ⎔ቃ DOC ࡟ࡘ࠸࡚ࠊศᏊࢧ࢖ࢬูࡢ⏕ᙜࢭࣥࢱ࣮ࡣࡇࢀࡲ࡛࡟ࡶࠊ㞴ศゎᛶ᭷ᶵ≀࡜᫆ศゎᛶ᭷ᶵ≀ࡢ⃰ᗘࡢ᫬✵㛫ศᕸࡸࠊ㞴ศゎᛶ᭷ᶵ≀ࡢ⏕ែ⣔࡬ศゎ㐣⛬ࢆ┤᥋࠿ࡘ㛗ᮇⓗ࡟ㄪ࡭ࡓ◊✲ࡣୡ⏺ⓗ࡟ஈࡋ࠿ࡗࡓࠋࡢᙳ㡪࡞࡝࡟ࡘ࠸࡚◊✲ࢆ㐍ࡵ࡚ࡁࡓ㸦➨஧ᮇ୰ᮇィ⏬㸸ࡇࢀࡽࡢ▱ぢࢆ⫼ᬒ࡜ࡋ࡚ࠊᮏ◊✲㸦➨஬ᮇ୰ᮇィ⏬㸧ᒸᮏࡽ, 2011; ➨୕ᮇ୰ᮇィ⏬㸸᪩ᕝࡽ, 2015 ࡞࡝㸧ࠋ➨ᅄ࡛ࡣࡲࡎࠊ†Ỉ୰᭷ᶵ≀ࡢ㉳※≉ᐃ࡟ྥࡅࡓࡉࡽ࡞ࡿᡭἲ

ᮇ୰ᮇィ⏬࡛ࡣࠊ᭷ᶵ≀ࡢ㉳※ࡸ⏕ศゎ㐣⛬ࡢホ౯ࡢᡭἲ㛤Ⓨࢆ┠ⓗ࡜ࡋ࡚ࠊδ13C ศᯒࢆ⏝࠸ࡓ◊✲ࢆ⥅⥆ࡋࡓࠋࡢࡦ࡜ࡘ࡜ࡋ࡚ࠊⅣ⣲Ᏻᐃྠ఩యẚ㸦δ13C㸧ศᯒࢆヨࡳࡓ

2016 ᖺ 5 ᭶㹼2017 ᖺ 2 ᭶࡜ࠊ2018 ᖺ 8 ᭶ࡢ⍇⍈†໭†⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮◊✲ሗ࿌᭩➨ 16 ྕ

69

17B ᆅⅬࡢ⾲ᒙ†Ỉ࡟ࡘ࠸࡚ࠊ⏕ศゎヨ㦂ヨᩱࡢ δ13C ್ Ỉヨᩱࡢℐ㐣࡜᭷ᶵ≀ࡢᐃ㔞ࢆศᯒࡋࠊ➨ᅄᮇࡢ⤖ᯝ࡜ྜࢃࡏ࡚ࠊ⤒ᖺⓗ࡞ኚ໬ࢆ㏣㊧⍇⍈††Ỉࡢ࠺ࡕ 2016 ᖺ 5 ᭶㹼2017 ᖺ 2 ᭶ࡢ⏕ศゎヨ13C

ࡋࡓࠋDOC ࡟ຍ࠼࡚ࠊPOC ࡟ࡘ࠸࡚ࡶࠊ⏕ศゎᛶ࡜ δ㦂࡛ࡣࠊ0ࠊ7ࠊ28ࠊ100 ᪥┠ࡢヨᩱ࡟ࡘ࠸࡚ࠊ࢞ࣛࢫ〇 GF/B್ࡢ㛵ಀᛶ࡟ࡘ࠸࡚ㄪ࡭ࡓࠋ኱ᆺ⥳⸴ࡀ POC ࡜ DOC ࡢࣇ࢕ࣝࢱ࣮㸦Whatmanࠊ┤ᚄ 47mmࠊᏍᚄ 1.0 μmࠊ450℃࡛

ືែ࡟୚࠼ࡿᙳ㡪ࡶࠊδ13C ್࠿ࡽ⪃ᐹࡋࡓࠋࡉࡽ࡟ࠊ㔝Ὢ

2 ᫬㛫ຍ⇕῭㸧࡛ℐ㐣ࢆ⾜࠸ࠊ⢏Ꮚែ᭷ᶵ≀࡜⁐Ꮡែ᭷ᶵᕝἙᕝỈ࡟ࡘ࠸࡚ࡶྠᵝ࡟⏕ศゎヨ㦂ࢆ⾜࠸ࠊ⍇⍈†ὶධ≀࡟ศࡅ࡚᥇ྲྀࡋࡓࠋ

ἙᕝỈ࡟ྵࡲࢀࡿ㝣ᇦ⏤᮶ RDOC ࡢ δ13C ್ࢆึࡵ࡚ᐇ
ࡋࡓࠋ2018 ᖺ 8 ᭶᥇ྲྀࡢ⍇⍈††Ỉ࡜ࠊ2019 ᖺ 8 ᭶᥇ྲྀࡢ㔝ὪᕝἙᕝỈࡢ⏕ศゎヨ㦂࡛ࡣࠊࡼࡾ㧗࠸᫬㛫ゎീᗘ࠿ࡘ㛗ᮏ◊✲࡛ࡣḟ࡟ࠊ†Ỉ୰᭷ᶵ≀ࡢ㞴ศゎ/᫆ศゎẚ⋡ࢆᮇ㛫ࡢኚ໬ࢆ㏣㊧ࡍࡿࡓࡵ࡟ࠊࡑࢀࡒࢀ 0ࠊ1ࠊ3ࠊ9ࠊ16ࠊ

㎿㏿࡟ᢕᥱ࡛ࡁࡿᡭἲ㛤Ⓨࢆ┠ⓗ࡜ࡋ࡚ࠊDOC ࡢศᏊࢧ23ࠊ30ࠊ53ࠊ101ࠊ205ࠊ402 ᪥┠࡜ࠊ0ࠊ7ࠊ12ࠊ26ࠊ53ࠊ

࢖ࢬศᯒ࡟╔┠ࡋ࡚◊✲ࢆ㐍ࡵࡓࠋ⍇⍈††Ỉ࠾ࡼࡧ㔝Ὢ

102ࠊ202 ᪥┠ࡢヨᩱ࡟ࡘ࠸࡚ࠊℐ㐣ࢆ⾜ࡗࡓࠋDOC ศᏊᕝἙᕝỈࡢ DOC ࡟ࡘ࠸࡚ࠊ㛗ᮇ⏕ศゎᐇ㦂࡟ࡼࡾศᏊࢧ

ࢧ࢖ࢬศᯒ࡞࡝௚ࡢ᭷ᶵ≀ศᯒ㡯┠࡟ࡶヨᩱࢆ⏝࠸ࡿࡓ࢖ࢬู࡟᭷ᶵⅣ⣲⏕ศゎ㏿ᗘࢆ᥎ᐃࡋࡓࠋࡑࡢ⤖ᯝ࡟ᇶ࡙ࡵࠊᚑ᮶ࡢ⏕ศゎヨ㦂࡜ࡣࠊℐ㐣ࡢᡭἲࡶኚ᭦ࡋࡓࠋ†Ỉ

ࡁࠊDOC ࡢศᏊࢧ࢖ࢬศᕸࢆᣦᶆ࡜ࡋ࡚ࠊDOC ࡢ⏕ศゎ࡜ἙᕝỈࡢ 0 ᪥┠ヨᩱࡣࠊ᥇ྲྀᙜ᪥࡟ࠊࢼ࢖ࣟࣥ〇ࣉࣛࣥᛶࢆ㎿㏿࡟ᢕᥱ࡛ࡁࡿྍ⬟ᛶ࡟ࡘ࠸࡚⪃ᐹࡋࡓࠋࢡࢺࣥࢿࢵࢺ㸦150 μm ࣓ࢵࢩࣗࠊ㉸⣧Ỉ࡛Ὑί῭㸧ࠊ࢞ࣛ
ࢫ〇 GF/F ࣇ࢕ࣝࢱ࣮
㸦Whatmanࠊ┤ᚄ 47mmࠊᏍᚄ 0.7 μmࠊ

 ᪉ἲ
 Ỉヨᩱࡢ᥇ྲྀ

450℃࡛ 5 ᫬㛫ຍ⇕῭㸧ࠊ࣏࣮ࣜ࢝࣎ࢿ࣮ࢺ〇 Nuclepore ࣇ࢕ࣝࢱ࣮㸦Whatmanࠊ┤ᚄ 47mmࠊᏍᚄ 0.2 μmࠊ㓟Ὑί῭㸧

2016 ᖺ 5 ᭶㹼2017 ᖺ 2 ᭶ࡢྛᏘ⠇㸦᫓㸸5 ᭶ࠊኟ㸸8 ᭶ࠊࢆ⏝࠸࡚ࠊ୕ẁ㝵ࡢℐ㐣࡛⢏Ꮚ≧᭷ᶵ≀࡜⣽⳦⣽⬊ࢆ㝖ཤ⛅㸸11 ᭶ࠊ෤㸸2 ᭶㸧࡟ࠊ⍇⍈†໭†ࡢ௒ὠἈ୰ኸ㸦17B㸸

ࡋࠊ⁐Ꮡែヨᩱ㸦<0.2 μm㸧ࢆ᥇ྲྀࡋࡓࠋ⏕ศゎヨ㦂ࡢヨᩱ†ᗏỈ῝ 89m㸧࡟࠾࠸࡚ࠊㄪᰝ⯪ࠕࡧࢃ࠿ࡐࠖ࡟ࡼࡾࠊ⾲ỈࡣࠊGF/F ࣇ࢕ࣝࢱ࣮㸦ྠୖ㸧࡜ Nuclepore ࣇ࢕ࣝࢱ࣮

ᒙ㸦Ỉ῝ 0.5m㸧ࡢ⍇⍈††Ỉࢆ᥇Ỉࡋࡓࠋ2018 ᖺ 8 ᭶࡟㸦ྠୖ㸧ࡢ஧ẁ㝵ࡢℐ㐣࡛ࠊ⁐Ꮡែヨᩱࢆ᥇ྲྀࡋࡓࠋ⁐Ꮡ

ࡣࠊྠᆅⅬࡢ⾲ᒙ㸦Ỉ῝ 5 m㸧࡟࠾࠸࡚ࠊྠᵝ࡟⍇⍈††ែヨᩱࡣࠊ࣏ࣜࣉࣟࣆࣞࣥ〇ᐜჾ㸦࢔࣭ࣝ࢝ࣜ㓟Ὑί῭㸧Ỉࢆ᥇Ỉࡋࡓࠋ⍇⍈††Ỉࡢ᥇ྲྀ᪥ࡣࠊࡑࢀࡒࢀᅗ 5-4 ࡟࡟ධࢀ࡚ࠊ-30℃࡛෭෾ࡋ࡚ಖᏑࡋ࡚ࠊᚋ᪥ࡢ δ13C ศᯒ࡜

グ㍕ࡋࡓࠋ⍇⍈†࡬ࡢὶධἙᕝࡢ௦⾲࡜ࡋ࡚ࠊ㔝ὪᕝࡢἙศᏊࢧ࢖ࢬศᕸศᯒ࡟⏝࠸ࡓࠋཱྀ௜㏆ࡢἙᕝỈࢆࠊ2019 ᖺ 8 ᭶ 9 ᪥࡟᭹㒊኱ᶫ࡛ࢫࢸࣥ

ࣂࣝࢡ DOC ⃰ᗘࡣࠊ඲᭷ᶵⅣ⣲ィ TOC-L ࡲࡓࡣ TOCV㸦ᓥὠ〇సᡤ㸧ࢆ⏝࠸࡚ࠊ᪩ᕝࡽ (2019) ࡟グ㍕ࡉࢀࡓᡭࣞࢫ〇ࣂࢣࢶࢆ⏝࠸࡚᥇Ỉࡋࡓࠋ

ἲ࡟ࡼࡾᐃࡋࡓࠋPOC ⃰ᗘࡣࠊ࢞ࣛࢫ〇ࣇ࢕ࣝࢱ࣮ୖࡢ

 ᭷ᶵ≀ࡢ㛗ᮇ⏕ศゎヨ㦂⢏Ꮚࢆ NC ࢔ࢼࣛ࢖ࢨ࣮㸦SUMIGRAPH NC-22F㸧࡛ 2016 ᖺ 5 ᭶㹼2017 ᖺ 2 ᭶࡟᥇ྲྀࡋࡓ⍇⍈††Ỉ࡟ࡘ࠸ࡋࡓࠋᐃ࡚ࡣࠊ➨ᅄᮇ࡟⏕ศゎヨ㦂ࡢ⤖ᯝࢆሗ࿌ࡋࡓ 2014 ᖺ 11 ᭶㹼2016 ᖺ 2 ᭶ࡢヨᩱ࡜ྠࡌᡭἲ࡛ࠊ100 ᪥㛫ࡢ⏕ศゎヨ㦂ࢆ⾜ࡗࡓࠋ†Ỉࡣ๓ฎ⌮ࢆࡏࡎ࡟ࠊ2L ࣏࣮ࣜ࢝࣎ࢿ࣮ࢺ〇 Nalgene ᐜჾ࡟ධࢀࠊ୍ᐃ

 Ⅳ⣲Ᏻᐃྠ఩యẚࡢᐃ

DOC ࡜ POC ࡢ δ13C ศᯒࡣࠊᅜ❧⎔ቃ◊✲ᡤ†἟࣭Ἑᕝᗘ㸦20℃㸧
ࠊᬯ᮲௳࡛ࠊỈ⎔ቃ◊✲ᐊࡢඖ⣲ศᯒィ㐃⤖ᆺᏳᐃྠ఩యẚ㉁㔞ศᯒィ

ᖹ᣺࡜࠺(60 ᅇ/ศ)ࢆ⾜ࡗࡓ㸦బ⸨ࡽ, 2016; 㔠ࡽ, 2018㸧
ࠋ

㸦EA-IRMS㸸Flash EA1112/Conflo III/Delta Plus Advantage,

࣏࣮ࣜ࢝࣎ࢿ࣮ࢺ〇 Nalgene ᐜჾࡣ஦๓࡟ࠊ࣌ࣝ࢜࢟ࢯ஧

Thermo Finnigan㸧ࢆ⏝࠸࡚ศᯒࡋࡓࠋᮏ⿦⨨ࡣ Ogawa et al.

◲㓟࣒࢝ࣜ࢘⁐ᾮ࡛‶ࡓࡋ࡚ 120℃࡛ 30 ศ㛫࣮࢜ࢺࢡࣞ

(2010) ࡢᡭἲࢆ୍㒊౑⏝ࡋ࡚ࠊ⣽⟶௙ᵝࡢ⇞↝⟶࡜㑏ඖ࣮ࣈࢆ࠿ࡅࡓᚋ࡟ࠊ㉸⣧Ỉ࡛Ὑίࢆ⾜ࡗࡓࠋ⟶ࢆ⏝࠸ࡿࡇ࡜࡛ࠊδ13C ศᯒࢆ㏻ᖖ௙ᵝࡼࡾࡶ㧗ឤᗘ໬ࡉ2018 ᖺ 8 ᭶᥇ྲྀࡢ⍇⍈††Ỉ࡜ࠊ2019 ᖺ 8 ᭶᥇ྲྀࡢ㔝ࢀ࡚࠸ࡿࠋⅣ⣲ྠ఩యẚࡢ್ࡣࠊᅜ㝿ᶆ‽≀㉁㸦Vienna PeeὪᕝἙᕝỈࡣࠊࡲࡎ᥇Ỉᚋ࡟ࣉࣛࣥࢡࢺࣥࢿࢵࢺ㸦150 μm

Dee Belemnite: VPDB㸧࡟ᑐࡍࡿ೫ᕪࡢ༓ศ⋡㸦͙㸧࡛♧ࡍࠋ࣓ࢵࢩࣗࠊ㉸⣧Ỉ࡛Ὑί῭㸧ࢆ⏝࠸࡚ 150 μm ௨ୖࡢ⢒኱

2016 ᖺ 5 ᭶㹼2017 ᖺ 2 ᭶ࡢ⍇⍈††Ỉࡢヨᩱࡣ DOC ࡜⢏Ꮚ࡜ࣉࣛࣥࢡࢺࣥࢆ㝖ཤࡋࡓࠋࡑࡢᚋࠊୖグ࡜ྠᵝࡢᡭPOC ࡢ୧᪉࡟ࡘ࠸࡚ࠊ2018 ᖺ 8 ᭶᥇ྲྀࡢ⍇⍈††Ỉ࡜ࠊἲ࡛ࠊ᭷ᶵ≀ࡢ⏕ศゎヨ㦂ࢆ⾜ࡗࡓࠋ2L ࣏࣮ࣜ࢝࣎ࢿ࣮

2019 ᖺ 8 ᭶᥇ྲྀࡢ㔝ὪᕝἙᕝỈࡢヨᩱࡣ DOC ࡢࡳ࡟ࡘ࠸ࢺ〇ᐜჾࡣࠊ⏕ศゎᐇ㦂ࡢヨᩱᩘᮏࢆ‽ഛࡋࠊ1 ᮏࡎࡘ 2L

࡚ࠊδ13C ศᯒࡢ⤖ᯝࢆ♧ࡍࠋ඲㔞ࢆℐ㐣࡟⏝࠸ࡓࠋ෌⌧ᛶࢆ☜ㄆࡍࡿࡓࡵࡢྛ᪥ࡢ⧞ࡾ
㏉ࡋヨᩱᩘࡣࠊࡑࢀࡒࢀ 2 Ⅼ࡜ࡋࡓࠋ70

DOC ヨᩱࡢ๓ฎ⌮࡛ࡣࡲࡎࠊ50mL ⛬ᗘࡢỈヨᩱࢆ࣏ࣜࣉࣟࣆࣞࣥ〇ᐜჾ࡟ධࢀࡓࡲࡲ෾⤖஝⇱ฎ⌮ࡋࡓᚋࠊሷ㓟⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ヨ㦂◊✲ሗ࿌᭩➨ 16 ྕ⵨Ẽ࡟ࡉࡽࡋ࡚↓ᶵⅣ⣲ࢆ㝖ཤࡋࡓࠋࡑࡢᐜჾࡢᗏ࡟ṧᏑ࠿࡟పୗࡍࡿഴྥࡀぢࡽࢀࡓ㸦⾲ᒙ࡛-26.7‰→-27.2‰㸧୍ࡋࡓ᭷ᶵ≀ࢆࠊGF/B ࡲࡓࡣ GF/F ࣇ࢕ࣝࢱ࣮㸦450℃ຍ⇕᪉࡛ࠊPOC ࡢ δ13C ್ࡣࠊ௚ࡢᏘ⠇࡜ẚ࡭࡚≉࡟㧗࠸್࡜῭㸧ࡢ 5mm ᅄ᪉⛬ᗘࡢᑠ∦࡟௜╔ࡉࡏ࡚᥇ྲྀࡋ࡚ࠊࣇ࢕

࡞ࡾࠊศゎ㐣⛬࡟࠾࠸࡚ࡉࡽ࡟㧗ࡃ࡞ࡗ࡚࠸ࡃഴྥࡀぢࡽࣝࢱ࣮ᑠ∦ࢆࢫࢬ࢝ࢵࣉ࡟ໟࢇ࡛ศᯒ࡟⏝࠸ࡓࠋPOC ヨࢀࡓࠋ࡞࠾ࠊྠ᫬ᮇ࡟ࡣ኱ᆺ⥳⸴࣑ࢡࣛࢫࢸࣜ࢔ࢫ࣭ࣁ࣮

ᩱࡢ๓ฎ⌮࡛ࡣࡲࡎࠊ஝⇱ฎ⌮ࡋࡓ࢞ࣛࢫ〇ࣇ࢕ࣝࢱ࣮ࢆ

ࢹ࢕ࡀቑຍࡋ࡚࠸ࡓࠋ

ሷ㓟⵨Ẽ࡟ࡉࡽࡋ࡚↓ᶵⅣ⣲ࢆ㝖ཤࡋ࡚⏝࠸ࡓࠋࡑࡢࣇ࢕
ࣝࢱ࣮ࡢℐ㐣ୖ᪉ഃࡢ⾲㠃ࢆࣆࣥࢭࢵࢺ࡛ࡣࡀࡋࠊࢫࢬ࢝
ࢵࣉ࡟ໟࢇ࡛ศᯒ࡟⏝࠸ࡓࠋ⣙ 100 ᪥⤒㐣ᚋࡢヨᩱࡢ᭷ᶵ≀ࢆࠊRDOC
δ13C ศᯒ࡛ࡣࠊ
࠾ࡼࡧ㞴ศゎᛶ POC㸦RPOC㸧࡜ᐃ⩏ࡋࡓࠋ㞴ศゎᛶ⏬ศ࡜᫆ศゎᛶ⏬ศࡢ஧ᡂศΰྜࣔࢹࣝࢆ௬ᐃࡋ࡚ࠊ0 ᪥┠࠿ࡽ⣙ 100 ᪥ᚋ࡟࠿ࡅ࡚ࡢ⃰ᗘ࡜ δ13C ್ࡢኚ໬࠿ࡽࠊLDOC࡜᫆ศゎᛶ POC㸦LPOC㸧ࡢ δ13C ್ࢆ⟬ฟࡋࡓࠋ ⁐Ꮡ᭷ᶵⅣ⣲ࡢศᏊࢧ࢖ࢬศᕸศᯒ
2018 ᖺ 8 ᭶᥇ྲྀࡢ⍇⍈††Ỉ࡜ࠊ2019 ᖺ 8 ᭶᥇ྲྀࡢ㔝ὪᕝἙᕝỈࡢ⏕ศゎヨ㦂ࡢ⁐Ꮡែヨᩱ࡟ࡘ࠸࡚ࠊᅜ❧⎔ቃ◊✲ᡤ⍇⍈†ศᐊࡀ⊂⮬࡟㛤Ⓨࡋࡓࢧ࢖ࢬ᤼㝖ࢡ࣐ࣟࢺࢢࣛࣇ඲᭷ᶵⅣ⣲ィ㸦SEC-TOC㸧ࢆ⏝࠸࡚ࠊShimotori et al.
(2016)ࡢᡭἲ࡟ࡼࡾࠊDOC ࡢศᏊࢧ࢖ࢬศᕸࢆ

ᐃࡋࡓࠋศᏊ㔞 10 ୓ Da ⛬ᗘࡢࣆ࣮ࢡࢆ㧗ศᏊ DOCࠊศᏊ㔞ᩘⓒ㹼ᩘ༓ Da ⛬ᗘࡢࣆ࣮ࢡࢆపศᏊ DOC ࡜ᐃ⩏ࡋࡓ㸦ᚋ㏙
ࡢᅗ 5-6 ཧ↷㸧ࠋ㧗ศᏊ DOC ࡟ࡘ࠸࡚ࡣࠊ᳨ฟ㝈⏺௨ୖࡢ⃰ᗘࢹ࣮ࢱࡀ
ᚓࡽࢀࡓ⤒㐣᫬Ⅼࡲ࡛㸦⍇⍈†⾲ᒙ†Ỉࡣ 53 ᪥┠ࠊ㔝ὪᕝἙᕝỈࡣ 26 ᪥┠ࡲ࡛㸧ࠊࠕ⏕ศゎ㐣⛬ࡣศゎ㏿ᗘᐃᩘࡀ୍ᐃࡢ୍ḟ཯ᛂ࡜ࡋ࡚㏆ఝ࡛ࡁࡿࠖ࡜ࡢ௬ᐃࢆ⨨࠸࡚ࠊᣦᩘ㛵ᩘ㏆ఝ࡟ࡼࡾศゎ㏿ᗘᐃᩘࢆ⟬ฟࡋࡓࠋపศᏊ DOC

ᅗ 5-1 2016 ᖺᗘࡢ⍇⍈†௒ὠἈ୰ኸ㸦17B㸧⾲ᒙ†Ỉ࡟࡜ࣂࣝࢡ DOC ࡟ࡘ࠸࡚ࡣࠊᩘⓒ᪥ࢫࢣ࣮ࣝࡢ㞴ศゎᛶ⏬

࠾ࡅࡿࠊᏘ⠇ࡈ࡜ࡢ⏕ศゎヨ㦂ᇵ㣴᪥ᩘ࡜ δ13C ್ࡢ᥎⛣

ศ㸦RDOC㸧࡜‽᫆ศゎᛶ⏬ศ㸦SLDOC㸧ࡢ஧ᡂศΰྜࣔ

㸦ୖ㸸DOCࠊୗ㸸POC㸧ࢹࣝࢆ௬ᐃࡋ࡚ࠊSLDOC ࡢ⃰ᗘࢆ⟬ฟࡋࡓࠋ⍇⍈†⾲ᒙ†Ỉࡣ 402 ᪥┠ࠊ㔝ὪᕝἙᕝỈࡣ 202 ᪥┠ࡢ⃰ᗘࢆ RDOC

2018 ᖺ 8 ᭶࡟᥇ྲྀࡋࡓ⍇⍈††Ỉ࡟ࡘ࠸࡚⏕ศゎヨ㦂ࡢ್࡜ࡋࡓࠋࡇࡢࡓࡵࠊδ13C ศᯒ࡜ࡣࠊRDOC ࡢᐃ⩏ࡀ␗ࢆ⾜ࡗࡓ⤖ᯝࠊ17B ⾲ᒙ㸦Ỉ῝ 5m㸧ࡢ DOC ࡢ δ13C ್ࡣࠊ࡞ࡗ࡚࠸ࡿࠋపศᏊ SLDOC ࡜ࣂࣝࢡ SLDOC ࡟ࡘ࠸࡚ࠊ

⣙ 400 ᪥㛫ࡢศゎ㐣⛬࡟࠾࠸࡚኱ࡁ࡞ኚ໬ࡣ࡞ࡃ࡯ࡰ୍

㧗ศᏊ DOC ࡜ྠᵝ࡟ศゎ㏿ᗘᐃᩘࢆ⟬ฟࡋࡓࠋᐃࡢ್-26㹼-27͙࡛࠶ࡗࡓࠋ୍᪉࡛ࠊ2019 ᖺ 8 ᭶࡟᥇ྲྀࡋ
ࡓ㔝ὪᕝἙᕝỈࡣࠊ⣙ 100 ᪥㛫ࡢศゎ㐣⛬࡟࠾࠸࡚-26.5

 ⤖ᯝ Ⅳ⣲Ᏻᐃྠ఩యẚ ᐃ࡟ࡼࡿ⍇⍈†࡟࠾ࡅࡿ᭷ᶵ≀ࣇ࣮ࣟࡢ≧ἣᢕᥱᡭἲࡢ᳨ウ

㹼-29.2͙⛬ᗘ࡛࠶ࡾࠊ⍇⍈††Ỉ࡜ẚ࡭࡚ప࠸್࡛࠶ࡗࡓ
㸦ᅗ 5-2㸧ࠋ 2014 ᖺ 11 ᭶࠿ࡽ 2017 ᖺ 2 ᭶࡟࠿ࡅ࡚ᐇ᪋ࡋࡓ 17B ⾲2016 ᖺᗘ࡟᥇ྲྀࡋࡓ⍇⍈††Ỉ࡟ࡘ࠸࡚⏕ศゎヨ㦂ࢆᒙࡢ⏕ศゎヨ㦂ࡢ⤖ᯝ࡟ࡘ࠸࡚ࠊDOC ⃰ᗘ࡜ POC ⃰ᗘࢆ⾜ࡗࡓ⤖ᯝࠊ17B ⾲ᒙࡢ DOC ࡢ δ13C ್ࡣࠊ⣙ 100 ᪥㛫ࡢ㞴᫆ศゎᛶู࡟ศࡅ࡚ᅗ 5-3 ࡟♧ࡍࠋLTOC㸦LPOC ࡜ศゎ㐣⛬࡟࠾࠸࡚ࠊኟᏘࢆ㝖࠸࡚ᶓࡤ࠸ࡶࡋࡃࡣపୗࡋ࡚

LDOC ࡢྜィ㸧࡟ࡣᏘ⠇ᕪࡀㄆࡵࡽࢀࡿࡀࠊRTOC㸦RPOC࠸ࡃഴྥࡀぢࡽࢀࡓ㸦ᅗ 5-1 ୖ㸧ࠋ୍᪉࡛ࠊ17B ⾲ᒙࡢ POC

࡜ RDOC ࡢྜィ㸧࡜ࡋ࡚ࡣ 1.0 mgC/L ๓ᚋ࡛࠶ࡾᏘ⠇࡟13

ࡢ δ C ್ࡣ㸪⣙ 100 ᪥㛫ࡢศゎ㐣⛬࡟࠾࠸࡚ࠊᶓࡤ࠸ࡶ

ࡼࡿ㐪࠸ࡣㄆࡵࡽࢀ࡞࠿ࡗࡓࠋࡇࡢഴྥࡣࠊ➨ᅄᮇ࡛ሗ࿌

ࡋࡃࡣ㧗ࡃ࡞ࡗ࡚࠸ࡃഴྥࡀぢࡽࢀࡓ㸦ᅗ 5-1 ୗ㸧ࠋ≉࡟ࠊࡋࡓഴྥ࡜ྠᵝ࡛࠶ࡗࡓࠋ

2016 ᖺ⛅Ꮨ࡟࠾࠸࡚ࠊ17B ⾲ᒙࡢ DOC ࡢ δ13C ್ࡣ᫂ࡽ⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮◊✲ሗ࿌᭩➨ 16 ྕ

71

11 ᭶ࡣࠊ኱ᆺ⥳⸴࣑ࢡࣛࢫࢸࣜ࢔ࢫ࣭ࣁ࣮ࢹ࢕ࡢࣈ࣮࣒ࣝ
࡜㔜࡞ࡿ᫬ᮇ࡛࠶ࡗࡓ㸦ᅗ 5-4 ୗ㸧ࠋ2014 ᖺ 11 ᭶࠿ࡽ 2017 ᖺ 2 ᭶ࡲ࡛ࡢྛᏘ⠇࡟᥇ྲྀࡋࡓ
ྜィ 10 ᅇศࡢ POC ࡢ δ13C ್࡟ࡘ࠸࡚ࠊPOC ⃰ᗘ࡜ࡢ㛵ಀࢆ᳨ウࡋࡓ⤖ᯝࠊRPOC ⃰ᗘ࡜ศゎヨ㦂๓ࡢ POC ࡢ δ13C
್ࡢ┦㛵ಀᩘ㸦r ್㸧ࡣ 0.84 ࡜࡞ࡾ㸪ṇࡢ┦㛵ࡀぢࡽࢀࡓ㸦ᅗ 5-5 ୖ㸧ࠋࡲࡓࠊRPOC ⃰ᗘ࡜ 100 ᪥ศゎヨ㦂ᚋࡢ POC
ࡢ δ13C ್࡜ࡢ┦㛵ಀᩘࡣ 0.90 ࡛࠶ࡗࡓ㸦ᅗ 5-5 ୗ㸧ࠋ୍
᪉ࠊRDOC ⃰ᗘ࡜ DOC ࡢ δ13C ್࡟ࡣ┦㛵ࡀㄆࡵࡽࢀ࡞࠿
ࡗࡓࠋ
ᅗ 5-2 2018 ᖺ 8 ᭶᥇ྲྀࡢ⍇⍈††Ỉ࡜ࠊ2019 ᖺ 8 ᭶᥇ྲྀࡢ㔝ὪᕝἙᕝỈ࡟࠾ࡅࡿࠊ⏕ศゎヨ㦂ᇵ㣴᪥ᩘ࡜ DOC
ࡢ δ13C ್ࡢ᥎⛣㸦㔝Ὢᕝ࡟ࡘ࠸࡚ࡣࠊ0ࠊ26ࠊ53ࠊ102 ᪥┠ࡢヨᩱ࡟ࡘ࠸࡚ศᯒࡋࡓ⤖ᯝ㸧

ᅗ 5-3 ⍇⍈†௒ὠἈ୰ኸ㸦17B㸧⾲ᒙ†Ỉ࡟ྵࡲࢀࡿ᭷
ࠊ᫆ศゎᛶ DOC
ᶵⅣ⣲ࡢ࠺ࡕࠊ᫆ศゎᛶ POC㸦LPOC㸧
㸦LDOC㸧
ࠊ㞴ศゎᛶ POC㸦RPOC㸧ࠊ㞴ศゎᛶ DOC㸦RDOC㸧ࡢ⃰ᗘࡢᏘ⠇ኚ໬ࠋ2014 ᖺ 11 ᭶㹼2016 ᖺ 2 ᭶ࡢ⤖ᯝࡣࠊࠋ➨ᅄᮇ࡟ሗ࿌ࡋࡓ್ࢆᘬ⏝ࡋࡓ㸦㔠ࡽ, 2018㸧
ᅗ 5-4 ⍇⍈†௒ὠἈ୰ኸ㸦17B㸧⾲ᒙ࡟࠾ࡅࡿ⏕ศゎヨ 2014 ᖺ 11 ᭶࠿ࡽ 2018 ᖺ 8 ᭶࡟࠿ࡅ࡚ᐇ᪋ࡋࡓ⍇⍈†㦂๓ᚋࡢ δ13C ್ࡢ᥎⛣㸦ୖ㸸DOC㸦㔝Ὢᕝ DOC ࡢ δ13C

⾲ᒙ†Ỉࡢ⏕ศゎヨ㦂๓ᚋࡢ δ13C ್ࡢ᥎⛣࡟ࡘ࠸᳨࡚ウ್ࢆྵࡴ㸧ࠊୗ㸸POC㸧
ࠋ0 ᪥┠ࡢ್ࢆࣂࣝࢡ㸦඲㔞㸧࡜ࡋࠊࡋࡓ⤖ᯝࠊDOC ࡜ POC ࡢ୧᪉࡛ࠊྛᏘ⠇࡟ඹ㏻ࡍࡿഴྥ

⣙ 100 ᪥㛫ࡢศゎヨ㦂ᚋ࡟ RDOC ࡶࡋࡃࡣ RPOC ࡢ δ13C

ࡣぢࡽࢀࡎࠊᖺ࡟ࡼࡗ࡚␗࡞ࡗࡓࠋࡲࡓࠊ2019 ᖺ 8 ᭶ࡢ್ࢆ㔝ὪᕝἙᕝỈࡢ RDOC ࡢ δ13C ್ࡣࠊ2016 ᖺ 2 ᭶௨እࡢ⍇್࡛࠶ࡿࠋ2014 ᖺ 11 ᭶㹼2016 ᖺ 2 ᭶ࡢ⤖ᯝࡣࠊ➨ᅄᮇ⍈††Ỉࡢ್࡜ẚ࡭࡚ప࠸್࡛࠶ࡗࡓ㸦ᅗ 5-4 ୖ㸧ࠋ࡟ሗ࿌ࡋࡓ್㸦㔠ࡽ, 2018㸧ࢆᘬ⏝ࡋ࡚♧ࡋࡓࠋ2017 ᖺ 2⍇⍈††Ỉࡢ DOC ࡢ δ13C ್ࡣࠊ≉࡟ኟᏘ㸦8 ᭶㸧࡟࠾
࠸࡚ࠊLDOC ࡜ RDOC ࡢ㛵ಀࡀᖺ࡟ࡼࡗ࡚኱ࡁࡃ␗࡞ࡿ

ᐃࠊLDOC ࡜ LPOC ࡢ δ13C ್ࡣィ⟬࡟ࡼࡾồࡵࡓ᭶ࡢ LPOC ࡢ δ13C ್ࡣࠊLPOC ⃰ᗘࡀప࠿ࡗࡓࡓࡵࠊㄗ
ᕪࡀ኱ࡁ࠸ྍ⬟ᛶࡀ࠶ࡿࠋഴྥࡀぢࡽࢀࡓࠋྛᖺࡢ†Ỉ᥇ྲྀࡢ┤๓㸦7 ᭶㸧࡟ࡣࠊ2015ᖺࡣ⸛⸴ࡢࢦࣥࣇ࢛ࢫࣇ࢙ࣜ࢔࡜኱ᆺ⥳⸴ࡢࢫࢱ࢘ࣛࢫ
ࢺ࣒࡛ࣝᵓᡂࡉࢀࡿࣈ࣮࣒ࣝࡀࠊ2016 ᖺ࡜ 2018 ᖺࡣ୺࡟ ศゎ࡟క࠺⁐Ꮡ᭷ᶵ≀ศᏊࢧ࢖ࢬศᕸ
ࡢኚ໬ࢫࢱ࢘ࣛࢫࢺ࣒࡛ࣝᵓᡂࡉࢀࡿࣈ࣮࣒ࣝࡀⓎ⏕ࡋ࡚࠸ࡓࠋ

⍇⍈†⾲ᒙ†Ỉ࡜㔝ὪᕝἙᕝỈࡢ୧᪉࡛ࠊSEC-TOC ศ

୍᪉ࠊPOC ࡢ δ13C ್ࡀ≉␗ⓗ࡟㧗࠸್࡛࠶ࡗࡓ 2016 ᖺᯒ࡛ࡣࠊ㧗ศᏊ DOC
㸦㔜㔞ᖹᆒศᏊ㔞㸻13 ୓㹼15 ୓⛬ᗘ㸧72⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ヨ㦂◊✲ሗ࿌᭩➨ 16 ྕ࡜ࠊపศᏊ DOC㸦㔜㔞ᖹᆒศᏊ㔞㸻1300 ⛬ᗘ㸧ࡢ஧ࡘࡢ㏿ᗘᐃᩘࡢ್ࡶࠊᅗ 5-7 ࡟♧ࡋࡓࠋᮏ◊✲࡜ Hama et al.

ࣆ࣮ࢡ࡟ศ࠿ࢀࡓ㸦ᅗ 5-6㸧ࠋᐇ㦂 0 ᪥┠࡛ࡢ୧⪅ࡢ⃰ᗘࡣ

(2004)࡛ࡣࠊศᏊࢧ࢖ࢬูศ⏬࡜ศゎ㏿ᗘᐃᩘ⟬ฟࡢᡭἲࡑࢀࡒࢀࠊ⍇⍈†⾲ᒙ†Ỉ࡛ࡣ 0.132 mgC/Lࠊ1.025 mgC/Lࠊࡣ␗࡞ࡿࡶࡢࡢࠊᴫࡡྠᵝࡢഴྥࡀぢࡽࢀࡓࠋ㔝ὪᕝἙᕝỈ࡛ࡣ 0.09 mgC/Lࠊ1.093 mgC/L ࡔࡗࡓࠋࣂࣝ
ࢡ DOC ⃰ᗘ࡟༨ࡵࡿ㧗ศᏊ DOC ⃰ᗘࡢ๭ྜࡣࠊ⍇⍈†⾲ᒙ†Ỉ࡛ 11%ࠊ㔝ὪᕝἙᕝỈ࡛ 8%ࡔࡗࡓࠋᅗ 5-6 ⏕ศゎ࡟క࠺ DOC ศᏊࢧ࢖ࢬศᕸࡢኚ໬ࡢ౛ࠋ
ࡇࡇ࡛ࡣࠊ⍇⍈†⾲ᒙ†Ỉࡢᐇ㦂 0 ᪥┠㸦㯮⥺㸧࡜ᐇ㦂
205 ᪥┠㸦◚⥺㸧ࡢ᭷ᶵⅣ⣲⃰ᗘࢆ♧ࡋࡓࠋ⦪㍈ࡣࠊᐇ㦂0 ᪥┠ࡢపศᏊ DOC ࡢ㧗ࡉࢆ 1 ࡜ࡋ࡚つ᱁໬ࡋ࡚ࠊ┦ᑐᙉᗘ࡜ࡋ࡚♧ࡋࡓࠋᶓ㍈ࡣࠊᕥഃࡀ㧗ศᏊࠊྑഃࡀపศᏊ
࡜ࡋ࡚ࠊศᏊ㔞㸦MW㸧ࢆࣟࢢࢫࢣ࣮࡛ࣝ♧ࡋࡓࠋ

ᅗ 5-5 ⍇⍈†௒ὠἈ୰ኸ㸦17B㸧⾲ᒙ࡟࠾ࡅࡿ㞴ศゎᛶ
POC ⃰ᗘ࡜ศゎヨ㦂๓ᚋࡢ POC ࡢ δ13C ್ࡢ┦㛵㸦ୖ㸸
0 ᪥┠ࠊୗ㸸100 ᪥┠㸧⏕ศゎࡢ㐍⾜࡟క࠸ࠊ㧗ศᏊ DOC ࡣẚ㍑ⓗ㏿ࡃῶᑡࡋᅗ 5-7 㛗ᮇ⏕ศゎᐇ㦂࠿ࡽ⟬ฟࡋࡓࠊ⍇⍈†⾲ᒙ†Ỉ࡜࡚ࠊ⍇⍈†⾲ᒙ†Ỉ࡛ࡣ 101 ᪥┠᫬Ⅼ࡛ࠊ㔝ὪᕝἙᕝỈ࡛㔝ὪᕝἙᕝỈࡢ DOC ࡢศᏊࢧ࢖ࢬูࡢศゎ㏿ᗘᐃᩘࠋ᳜

ࡣ 53 ᪥┠᫬Ⅼ࡛ࠊࡑࢀࡒࢀ᳨ฟ㝈⏺௨ୗࡢ⃰ᗘ࡟࡞ࡗࡓࠋ

≀ࣉࣛࣥࢡࢺࣥ DOC ࡢ್ࡣࠊẚ㍑ࡢࡓࡵ Hama et al.

పศᏊ DOC ࡟ࡣࠊ㞴ศゎᛶ⏬ศ㸦RDOC㸧ࡀྵࡲࢀࠊ⍇(2004) ࡼࡾᘬ⏝ࡋࡓࠋ⍈†⾲ᒙ†Ỉ࡛ࡣ 402 ᪥┠᫬Ⅼ࡛ 0.669 mgC/L㸦0 ᪥┠ࡢ
65%㸧ࡀࠊ㔝ὪᕝἙᕝỈ࡛ࡣ 202 ᪥┠᫬Ⅼ࡛ 0.808 mgC/L
㸦0 ᪥┠ࡢ 74%㸧ࡀࠊࡑࢀࡒࢀṧᏑࡋ࡚࠸ࡓࠋ
㧗ศᏊ DOCࠊపศᏊ DOC ࡜ࡶ࡟ࠊ⏕ศゎ࡟క࠺㔜㔞ᖹᆒศᏊ㔞ࡢኚ໬ࡣᑠࡉ࠿ࡗࡓࠋ

 ⪃ᐹ Ⅳ⣲Ᏻᐃྠ఩యẚศᯒ࡟ࡼࡿ᭷ᶵ≀ࡢ㉳※᥎ᐃ࠾ࡼࡧศゎᛶホ౯ᮏ◊✲࡛ࡣࠊ⍇⍈†ὶධἙᕝỈ࡟ྵࡲࢀࡿ㝣ᇦ⏤᮶⃰ᗘኚ໬࠿ࡽ⟬ฟࡋࡓࠊྛ DOC ⏬ศࡢศゎ㏿ᗘᐃᩘࢆ

RDOC ࡢ δ13C ್ࢆึࡵ࡚ᐇ

ࡋࡓࡇ࡜࡛ࠊ⍇⍈††Ỉ

ᅗ 5-7 ࡟♧ࡋࡓࠋ⍇⍈†⾲ᒙ†Ỉࠊ㔝ὪᕝἙᕝỈ࡜ࡶ࡟ࠊ

RDOC ࡢ㉳※᥎ᐃᡭἲࡢ୙☜ᐇᛶࢆῶᑡࡉࡏࡿࡇ࡜ࡀ࡛

㧗ศᏊ DOC ࡀࠊపศᏊ SLDOC ࡼࡾࡶ 2 ಸ⛬ᗘ㧗࠸್㸦㸻ࡁࡓࠋ㔝Ὢᕝࡢ RDOC ࡢ δ13C ್㸦-27.8͙㸧ࡣࠊኳ↛ DOC㏿࠸ศゎ㏿ᗘ㸧ࢆ♧ࡋࡓࠋẚ㍑ࡢࡓࡵ࡟ࠊHama et al. (2004)

㸦0 ᪥┠㸧ࡢ δ13C ್㸦-26.6͙㸧ࡼࡾࡶ᭷ព࡟ప࠸್࡜࡞ࡗ

ࡀሗ࿌ࡋࡓࠊ᳜≀ࣉࣛࣥࢡࢺࣥ⏤᮶ࡢ㧗ศᏊ DOC㸦1 ୓ࡓࡓࡵࠊἙᕝỈ࡟ྵࡲࢀࡿኳ↛ DOC ࡢ್ࡣࠊ㝣ᇦ⏤᮶Da ௨ୖ⏬ศ㸧࡜పศᏊ DOC㸦1 ୓ Da ௨ୗ⏬ศ㸧ࡢศゎ

RDOC ࡢ್ࢆ௦⾲ࡋ࡚࠸࡞࠸ྍ⬟ᛶࡀ♧ࡉࢀࡓࠋ௒ᅇࡢ㔝⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮◊✲ሗ࿌᭩➨ 16 ྕ

73Ὢᕝ RDOC ࡢ್ࡀࠊ⍇⍈†࡟ὶධࡍࡿ㝣ᇦ⏤᮶ RDOC ࢆ࣒ࣝࡀቑṪࡋ࡚࠸ࡿࡀ DOC ࡢ δ13C ್㸦RDOC㸸-26.0͙,࡝ࡢ⛬ᗘ௦⾲࡛ࡁࡿ࠿ࡣࠊ௒ᚋࡢ◊✲࡟ࡼࡿ☜ㄆࡀᚲせ࡜

LDOC㸸-26.8͙㸧ࡣࠊ2014-2016 ᖺࡢቑṪ᫬௨እࡢ DOC ࡢ࡞ࡿࠋࡋ࠿ࡋࠊ➨ᅄᮇ࡛ሗ࿌ࡋࡓすࡢ†ࡢ RDOC ࡢ್㸦-

δ13C ್ࡢ⠊ᅖෆ࡟཰ࡲࡗ࡚࠸ࡓࠋ

27.7͙㸧ࡀ࡯ࡰྠࡌ್࡛࠶ࡾࠊሙᡤ࡟ࡼࡿ㝣ᇦ⏤᮶ RDOC
13C ್ࡢᕪࡣᑠࡉ࠸ྍ⬟ᛶࡀ࠶ࡿࠋ

ࡢδࡓࡔࡋࠊ⍇⍈††Ỉࡢ RDOC ࡣ⃰ᗘࣞ࣋ࣝࡀࡑࡶࡑࡶ
㧗ࡃࠊቑṪࡢᐤ୚ࡀᑠࡉ࠸ࡇ࡜ࠊẚ㍑ⓗప࠸ δ13C ್ࢆᣢ†Ỉࡢࣂࣝࢡ POC ࠾ࡼࡧ RPOC ࡢ δ13C ್ࡣࠊ2016 ᖺࡘ㝣ᇦ⏤᮶ RDOC ࡜ẚ㍑ⓗ㧗࠸ δ13C ್ࢆᣢࡘ†ෆ⏕⏘⏤

11 ᭶࠾ࡼࡧ 2017 ᖺ 2 ᭶࡟㧗ࡃ࡞ࡿഴྥࡀぢࡽࢀ㸦ᅗ 5-4

᮶ RDOC ࡀΰྜࡋࡓࡶࡢ࡜⪃࠼ࡽࢀࡿࡇ࡜࠿ࡽࠊࡑࡢຠ

ୗ㸧ࠊ2016 ᖺ⛅Ꮨࡢ࣑ࢡࣛࢫࢸࣜ࢔ࢫ࣭ࣁ࣮ࢹ࢕࡞࡝ࠊ኱

ᯝࢆ⪃៖ࡍࡿᚲせࡀ࠶ࡿࠋᐇ㝿࡟⍇⍈†⾲ᒙ†Ỉࡢ RDOCᆺ⥳⸴ࡢࣈ࣮࣒ࣝࡢᐤ୚ࡀ♧၀ࡉࢀࡿࠋᮏሗ࿌᭩ࡢ➨ 3 ❶ࡢ δ13C ್ࡣࠊ2016 ᖺ 2 ᭶ࡢヨᩱ㸦-28.3͙㸧௨እࡣࠊ-25.2

ࠕἈᖏࡢ㣗≀⥙ᵓ㐀࠿ࡽࡳࡓ㨶㢮࡬ࡢ㣵㈨※ホ౯࡛ࠖࡣࠊ

㹼-27.4͙࡜ẚ㍑ⓗ⊃࠸⠊ᅖෆ࡟཰ࡲࡾࠊ㔝Ὢᕝ RDOC ࡼ

2017㹼2019 ᖺᗘࡢ⍇⍈†໭†ࡢ༡ẚⰋἈ୰ኸ㸦12B㸧ࡢࢧࡾࡶ㧗࠸್ࢆ♧ࡋࡓࠋ2014 ᖺ 11 ᭶㹼2018 ᖺ 8 ᭶ࡢ⍇⍈†࢖ࢬูࡢ POC ࡢ δ13C ್ࢆሗ࿌ࡋ࡚࠸ࡿࠋ኱ᆺ⥳⸴ࢆྵࡴ⾲ᒙ†Ỉ RDOC ࡢ δ13C ್ࡢ⠊ᅖ㸦-25.2㹼-28.3͙㸸ᖹᆒ㸻

45-250 μm ࡢࢧ࢖ࢬࡣࠊ20-45 μm ࡜<20 μm ࡢࢧ࢖ࢬࡼࡾ

26.4͙㸧࡜ࠊ㔝Ὢᕝ RDOC ࡢ δ13C ್㸦-27.8͙㸧ࠊ⍇⍈†࣎ࡶ㧗࠸್ࢆ♧ࡋ࡚࠸ࡿࠋ᫬ᮇ࡜ሙᡤࡣ␗࡞ࡿࡀࠊᮏ◊✲ࡢࢵࢡࢫࣔࢹ࡛ࣝ᥎ᐃࡉࢀࡓ㝣ᇦ⏤᮶ RDOC ࡜†ෆ⏕⏘⏤

13

2016 ᖺ 11 ᭶ࡢヨᩱ࡛ࡶࠊPOC ࡢ δ C ್ࡀ≉␗ⓗ࡟㧗ࡃ᮶ RDOC ࡢ๭ྜ㸦໭†࡛ࡑࢀࡒࢀ 49.0%࡜ 51.0%㸸బ⸨ࡽ,࡞ࡗ࡚࠾ࡾࠊ኱ᆺ⥳⸴ࡢ㧗࠸ δ13C ್ࡀ POC ඲యࡢ್࡟኱

2016㸧ࢆ⏝࠸ࡿ࡜ࠊ†ෆ⏕⏘⏤᮶ RDOC ࡢ δ13C ್ࡣ-22.7

ࡁࡃᙳ㡪ࡋࡓ࡜⪃࠼ࡽࢀࡿࠋྛᖺࡢ 11 ᭶࠿ࡽ 2 ᭶࡬ࡢ

㹼-28.8͙ࡢ⠊ᅖ㸦ᖹᆒ㸸-25.1͙㸧࡜ィ⟬ࡉࢀࡿࠋࡇࡢ್ࡣࠊ

POC ࡢ δ13C ್᥎⛣࡟╔┠ࡍࡿ࡜ࠊ2016 ᖺ 11 ᭶࠿ࡽ 2017

†Ỉ RDOC ඲యࡢ್ࡼࡾࡣ㧗࠸ഴྥ࡛࠶ࡿࡀࠊ኱ᆺ⥳⸴

ᖺ 2 ᭶࡬ࡢ᥎⛣ࡣ≉࡟ኚ໬ࡀ኱ࡁࡃᚠ⎔ᮇ࡟࠶ࡓࡿࡇ࡜

ࡀ♧ࡍ δ13C ್ࡢ⠊ᅖࡼࡾప࠸ࡲࡲ࡛࠶ࡾࠊศゎ㐣⛬࡟࠾࠿ࡽࠊ2016 ᖺ⛅Ꮨࡢ኱ᆺ⥳⸴⏤᮶ࡢ᭷ᶵ≀ࡀ඲ᒙ࡟ศᕸ

ࡅࡿྠ఩యศูࡢㄢ㢟ࡣ࠶ࡿࡀࠊ†Ỉ RDOC ࡢ㉳※࡟኱

ࡋࡓᚋࠊPOC ࡜ࡋ࡚῝Ỉᒙ࡬࡜ỿ㝆ࡋ࡚࠸ࡿྍ⬟ᛶࡀ♧ᆺ⥳⸴ࡢᐤ୚ࡀᑡ࡞࠸ࡇ࡜ࢆᨭᣢࡍࡿࠋ
ᮏሗ࿌᭩➨ 3 ❶࡛ࡣࠕ኱ᆺ⥳⸴ࡣື≀ࣉࣛࣥࢡࢺࣥ࡟ᤕ

၀ࡉࢀࡿࠋࡲࡓࠊRPOC ࡢ δ13C ್࡜ RPOC ⃰ᗘࡢ㧗࠸ṇࡢ┦㛵㛵㣗ࡉࢀ࡟ࡃࡃࠊ⏕㣗㐃㙐࡬ࡢᐤ୚ࡀᑠࡉ࠸ࠖ࡜࠸࠺⤖ᯝࡀಀ㸦ᅗ 5-5 ୗ㸧࠿ࡽࡣࠊ኱ᆺ⥳⸴⏤᮶࡛㧗࠸ δ13C ್ࢆᣢࡘᚓࡽࢀ࡚࠸ࡿࠋࡇࡢ⤖ᯝ࡜ࠊࠕ኱ᆺ⥳⸴⏤᮶ࡢ᭷ᶵ≀ࡣ†POC ࡀࠊRPOC ࡢ㉳※࡜ࡋ࡚㔜せ࡛࠶ࡿࡇ࡜ࡀ♧၀ࡉࢀ

Ỉ DOC ࡬ࡢᐤ୚ࡀᑠࡉ࠸ࠖ
ࠕ኱ᆺ⥳⸴ࡣ RPOC ࡢ㉳※࡜ࡿࠋࡉࡽ࡟ࠊRPOC ࡢ δ13C ್ࡔࡅ࡛࡞ࡃࠊ⏕ศゎヨ㦂๓ࡢࡋ࡚㔜せࠖ࡜࠸࠺ᮏ◊✲ࡢ⤖ᯝ࡜⥲ྜࡍࡿ࡜ࠊ኱ᆺ⥳⸴⏤13

ࣂࣝࢡ POC ࡢ δ C ್࡜ RPOC ⃰ᗘ࡟ࡶṇࡢ┦㛵㛵ಀࡀぢ᮶ࡢ᭷ᶵ≀ࡣࠊ኱㒊ศࡣ†⾲ᒙ࡟ࡣṧࡽࡎࠊPOC ࡜ࡋ࡚†ࡽࢀࡓࡓࡵ㸦ᅗ 5-5 ୖ㸧ࠊኳ↛†Ỉ POC ࡢ δ13C ್ࡀࠊ㞴ศ῝Ỉᒙ࡬࡜ỿ㝆ࡋ࡚࠸ࡿྍ⬟ᛶࡀ⪃࠼ࡽࢀࡿࠋ

ゎᛶ POC ࡢ⃰ᗘࡢᣦᶆ࡜ࡋ࡚᭷⏝࡞ྍ⬟ᛶࡀ࠶ࡿࠋ

ࡲࡓࠊᮏ◊✲࡛ሗ࿌ࡋࡓ 2014-2018 ᖺࡢ⾲ᒙ†Ỉ LDOC

୍᪉࡛ࠊDOC ࡢ δ13C ್ࡢ⤒ᖺ࣭Ꮨ⠇ኚື࠿ࡽࡣࠊ⍇⍈ࡢ δ13C ್㸦ᖹᆒ࡛-26.7͙㸧ࡣࠊMaki et al. (2010)࡛ሗ࿌ࡉ

††Ỉ DOC ࡢ㉳※࡜ࡋ࡚ࠊ኱ᆺ⥳⸴ࡢᐤ୚ࡀ㝈ᐃⓗ࡛࠶ࢀ࡚࠸ࡿ 2006-2007 ᖺࡢ್㸦-22͙⛬ᗘ㸧ࡼࡾࡶప࠸್࡜࡞

ࡾࠊ୰ᑠᆺ᳜≀ࣉࣛࣥࢡࢺࣥࢆ㉳Ⅼ࡟ࡋࡓ᭷ᶵ≀ࡀ㉳※࡜ࡗ࡚࠾ࡾࠊ†ෆࡢ≀㉁ᚠ⎔ࡢ㛗ᮇⓗ࡞ኚ໬ࢆ཯ᫎࡋ࡚࠸ࡿࡋ࡚㔜せ࡞ࡇ࡜ࡀ♧၀ࡉࢀࡿࠋ2014 ᖺ 11 ᭶࠿ࡽ 2018 ᖺྍ⬟ᛶࡀ࠶ࡿࠋ2014-2017 ᖺࡢ⾲ᒙ†Ỉ POC ࡣࠊ2006-2007

8 ᭶࡟࠿ࡅ࡚ࠊDOC ࡢ δ13C ್࡟ࡣࠊPOC ࡢࡼ࠺࡟㧗ࡃ࡞

ᖺ࡜ྠᵝ࡟ࠊ-22͙⛬ᗘ࠿ࡑࢀ௨ୖࡢ㧗࠸ δ13C ್ࢆ♧ࡍ᫬ࡿ⌧㇟ࡣぢࡽࢀ࡞࠿ࡗࡓ㸦ᅗ 5-4 ୖ㸧ࠋRDOC ࡜ LDOC ࡜ᮇࡶ࠶ࡾࠊ୍ḟ⏕⏘⪅඲యࡢ δ13C ್࡟㛗ᮇⓗ࡞ഴྥࡣぢࡶ࡟ࠊ2015 ᖺ 8 ᭶ࡢ LDOC㸦-22.6͙㸧௨እࡣࠊ඲࡚-25͙ࡽࢀ࡞࠸ࠋࡇࢀࡽࡢ⤖ᯝࡣ୍ぢࡋ࡚┦཯ࡍࡿࡼ࠺ࡔࡀࠊ⾲௨ୗࡔࡗࡓࠋ2015 ᖺ 8 ᭶ࡢ್࡟ࡣࠊ┤๓࡟㉳ࡁࡓࢦࣥࣇ

ᒙ†Ỉ LDOC ࡢ㉳※ࡀ୺࡟୰ᑠᆺ᳜≀ࣉࣛࣥࢡࢺࣥ⏤᮶࢛ࢫࣇ࢙ࣜ࢔㸦⸛⸴㸧ࡢࣈ࣮࣒ࣝࡀᙳ㡪ࡋ࡚࠸ࡿࡇ࡜ࡀ♧ࡢ᭷ᶵ≀࡛࠶ࡿ࡜ࡍࢀࡤࠊㄝ᫂ྍ⬟࡛࠶ࡿࠋࡘࡲࡾࠊ2014-၀ࡉࢀࡿࠋࡉࡽ࡟ 2016 ᖺ 11 ᭶࡟ࡣࠊ࣑ࢡࣛࢫࢸࣜ࢔ࢫ࣭

2017 ᖺࡢ⾲ᒙ†Ỉ POC ࡛ࡶ୰ᑠᆺ᳜≀ࣉࣛࣥࢡࢺࣥࡀඃ

ࣁ࣮ࢹ࢕㸦኱ᆺ⥳⸴㸧ࡢ኱ቑṪ࡟ࡼࡾ POC ࡢ δ13C ࡀ≉␗༨ࡋࡓ᫬ᮇ࡟ࡣ δ13C ್ࡀపࡃࠊࡲࡓᮏሗ࿌᭩➨ 3 ❶ࡢ⤖ⓗ࡟㧗࠸್ࢆ♧ࡋࡓ࡜⪃࠼ࡽࢀࡿࡀࠊDOC ࡢ δ13C ್ᯝ࡛ࡶ୰ᑠᆺ᳜≀ࣉࣛࣥࢡࢺࣥࡢ δ13C ್ࡀ኱ᆺ⥳⸴ࡼࡾ

㸦RDOC㸸-27.2͙ࠊLDOC㸸-25.4͙㸧ࡣ POC ࡜ࡣ኱ࡁࡃ␗

ࡶప࠸ࡇ࡜࠿ࡽࠊࡑࡢప࠸ δ13C ್ࡀ†Ỉ LDOC ࡟཯ᫎࡉ࡞ࡗࡓࠋ2015 ᖺࠊ2016 ᖺࡢኟ࡟ࡶࠊ†Ỉ᥇ྲྀࡢ๓࡟ࢫࢱ

ࢀࡓ࡜⪃࠼ࡽࢀࡿࠋ2006-2007 ᖺ࡟ࡣࠊ᫓Ꮨ㹼ኟᏘࡢ⾲ᒙ࢘ࣛࢫࢺ࣒ࣝ㸦኱ᆺ⥳⸴㸧ࡢࣈ࣮࣒ࣝࡀⓎ⏕ࡋ࡚࠸ࡿࡀࠊ

࡛ࡣࠊ◪㓟ሷࡣ୍ᐃ⃰ᗘṧᏑࡋ࡚࠸ࡓ୍᪉࡛ࠊ⁐Ꮡ CO2 ⃰POC ࡢ δ13C ࡣ 2016 ᖺ 11 ᭶࡯࡝࡛ࡣ࡞࠸ࡶࡢࡢẚ㍑ⓗ㧗ᗘࡀప࠿ࡗࡓࠋࡇࡢࡓࡵࠊ2006-2007 ᖺࡢ᫓Ꮨ㹼ኟᏘ࡟࠾࠸್ࢆ♧ࡋ࡚࠸ࡿࠋࡲࡓࠊ2018 ᖺ 8 ᭶࡟ࡶࢫࢱ࢘ࣛࢫࢺ

࠸࡚ࡣࠊ୰ᑠᆺ᳜≀ࣉࣛࣥࢡࢺࣥࡢάⓎ࡞⏕⏘᫬࡟ࡣࠊග

74⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ヨ㦂◊✲ሗ࿌᭩➨ 16 ྕྜᡂ࡟࠾ࡅࡿ⁐Ꮡ CO2 ࠿ࡽࡢⅣ⣲ྠ఩యศูࡀᑠࡉࡃࠊ

Ꮚࢧ࢖ࢬ࡜⏕ศゎᛶࡀ┦㛵ࡍࡿ࣓࢝ࢽࢬ࣒࡟ࡘ࠸࡚ࡣࠊศ

13C ್ࡣ㧗࠿ࡗࡓ࡜⪃࠼ࡽࢀ࡚࠸ࡿ

⏕⏘ࡉࢀࡓ᭷ᶵ≀ࡢ δᏊࢧ࢖ࢬูࡢ DOC ໬Ꮫ⤌ᡂศᯒ࡞࡝ࠊ௒ᚋࡉࡽ࡟◊✲ࡀ

㸦Maki et al., 2010㸧ࠋ୍᪉࡛ࠊ2006-2007 ᖺ࡟ẚ࡭࡚ࠊ2014-ᚲせ࡟࡞ࡿࠋ

2018 ᖺࡣࠊኟᏘ⾲ᒙ࡛ࡢ◪㓟ሷࡢᯤῬࡀ㢧ⴭ࡟࡞ࡗ࡚࠾

ࡇࡢ୕⏬ศ㸦㧗ศᏊ DOCࠊపศᏊ SLDOCࠊపศᏊ RDOC㸧ࡾࠊ≉࡟ኟᏘࡢ୰ᑠᆺ᳜≀ࣉࣛࣥࢡࢺࣥࡢ⏕⏘ࡀ୺࡟ᰤ㣴ࡢ๭ྜࡣࠊኳ↛ࡢ†Ỉ࣭ἙᕝỈࡢ DOC ࡢ⏕ศゎᛶ࡜ศゎ

ሷ࡟ᚊ㏿ࡉࢀ࡚࠸ࡓ࡜⪃࠼ࡽࢀࡿࠋࡇࡢࡓࡵࠊගྜᡂ࡟࠾

㏿ᗘࡢᣦᶆ࡜ࡋ࡚᭷⏝࡛࠶ࡿྍ⬟ᛶࡀ࠶ࡿࠋࡇࡢ࠺ࡕࠊ㧗ࡅࡿ⁐Ꮡ CO2 ࠿ࡽࡢⅣ⣲ྠ఩యศูࡀ኱ࡁࡃ࡞ࡾࠊ୰ᑠ

ศᏊ DOC ࡜పศᏊ DOC ࡢ๭ྜࡣࠊSEC-TOC ศᯒ࠿ࡽ┤13ᆺ᳜≀ࣉࣛࣥࢡࢺࣥࡀ⏕⏘ࡋࡓ᭷ᶵ≀ࡢ δ C ್ࡣప࠿ࡗ

᥋⟬ฟ࡛ࡁࡿࠋ୍᪉࡛ࠊኳ↛ヨᩱࡢపศᏊ SLDOC ࡜పศࡓ࡜⪃࠼ࡽࢀࡿࠋ

Ꮚ RDOC ࡢ๭ྜࡢ⟬ฟ࡟ࡣࠊࡉࡽ࡞ࡿ◊✲ࡀᚲせ࡟࡞ࡿࠋ౛࠼ࡤࠊపศᏊ RDOC ࡢ⃰ᗘࡀᏘ⠇ࡸᆅⅬ࡛኱ࡁࡃኚ໬

 ⁐Ꮡ᭷ᶵ≀ࡢศᏊࢧ࢖ࢬ࡜⏕ศゎᛶࡢ㛵ಀࡋ࡞࠸ࡇ࡜ࡀ☜ㄆ࡛ࡁࢀࡤࠊSEC-TOC ศᯒ࡛ᚓࡽࢀࡿప
ศᏊ DOC ⃰ᗘࡢ᝟ሗࡔࡅ࠿ࡽࠊపศᏊ SLDOC ࡜పศᏊ㛗ᮇ⏕ศゎヨ㦂ヨᩱࡢศᏊࢧ࢖ࢬศᯒࡢ⤖ᯝ࠿ࡽࠊ⍇⍈RDOC ࡢ๭ྜࢆ⟬ฟ࡛ࡁࡿࠋࡲࡓࠊSEC-TOC ศᯒ࡛ࡣࠊ

†⾲ᒙ†Ỉ࡜㔝ὪᕝἙᕝỈࡢ DOC ࡣࠊ୕ࡘࡢ⏬ศ㸦ձ㧗

DOC ࡢ⺯ගᡂศ࣭྾ගᡂศࡢศᏊࢧ࢖ࢬศᕸࡶᢕᥱྍ⬟ศᏊ DOCࠊղపศᏊ SLDOCࠊճపศᏊ RDOC㸧ࡢΰྜ࡜࡛࠶ࡿࡓࡵࠊࡑࢀࡽࡢ᝟ሗ࠿ࡽࠊపศᏊ SLDOC ࡜పศᏊࡋ࡚㏆ఝ࡛ࡁࡿࡇ࡜ࡀ♧ࡉࢀࡓࠋྛ⏬ศࡢ≉ᛶ࡟ࡘ࠸࡚ࠊ

RDOC ࡢ๭ྜࢆ᥎ᐃ࡛ࡁࡿྍ⬟ᛶࡶ࠶ࡿࠋ

௨ୗ࡟ࡲ࡜ࡵࡿࠋձ 㧗ศᏊ DOC㸸㔜㔞ᖹᆒศᏊ㔞ࡣ 13 ୓㹼15 ୓⛬ᗘࢆ ࡲ࡜ࡵ

♧ࡍࠋศゎ㏿ᗘᐃᩘ㸦k-d㸧ࡀ 0.03㹼0.04 ⛬ᗘ࡜ẚ㍑ⓗ ᮏ◊✲࡛ࡣࠊ⍇⍈†ࡢ≀㉁ᚠ⎔࡟㔜せ࡞ࠊ†Ỉ୰᭷ᶵ≀㧗࠸‽᫆ศゎᛶᡂศ࡛࠶ࡾࠊ༙ῶᮇࡣ 16㹼23 ᪥⛬ᗘࡢ㉳※࡜⏕ศゎᛶࢆᢕᥱࡍࡿࡓࡵࡢᡭἲ࡜ࡋ࡚ࠊδ13C ศᯒ࡜࡞ࡿࠋࣂࣝࢡ DOC ⃰ᗘ࡟༨ࡵࡿ๭ྜࡣࠊ୕⏬ศࡢ࡜ศᏊࢧ࢖ࢬศᯒ࡟╔┠ࡋ࡚◊✲ࢆ㐍ࡵࡓࠋ୰࡛᭱ࡶᑠࡉࡃࠊᮏ◊✲࡛⏝࠸ࡓ⍇⍈†⾲ᒙ†Ỉ࡛ࡣ
11%ࠊ㔝ὪᕝἙᕝỈ࡛ࡣ 8%ࡔࡗࡓࠋղ పศᏊ SLDOC㸸㔜㔞ᖹᆒศᏊ㔞ࡣ 1300 ⛬ᗘ࡛ࠊపศ

ࡲࡎࠊ⍇⍈†ࡢ†Ỉ୰᭷ᶵ≀ࡢ㉳※≉ᐃ࡟ྥࡅࡓᡭἲࡢ
㛤Ⓨ࡜ࡋ࡚ࠊδ13C ศᯒࢆ⏝࠸ࡓ◊✲ࢆ㐍ࡵࡓࠋ㔝ὪᕝἙᕝỈࡢ⏕ศゎヨ㦂࡟ࡼࡾࠊ⍇⍈†ὶධἙᕝỈ࡟ྵࡲࢀࡿ㝣ᇦ

Ꮚ RDOC ࡜࡯ࡰኚࢃࡽ࡞࠸ࠋ‽᫆ศゎᛶᡂศ࡛ࡣ࠶

⏤᮶ RDOC ࡢ δ13C ್ࢆึࡵ࡚ᐇ

ࡿࡀࠊศゎ㏿ᗘᐃᩘ㸦k-d㸧ࡣ 0.014㹼0.02 ⛬ᗘ࡛ࠊ㧗⏕ศゎヨ㦂ヨᩱࡢ POC ࡜ DOC ࡢ δ13C ್ࡢ⤒ᖺ࣭Ꮨ⠇ኚ

ศᏊ DOC ࡼࡾప࠸ࠋ
༙ῶᮇࡣ 34㹼51 ᪥⛬ᗘ࡜࡞ࡿࠋ

ື࠿ࡽࡣࠊศゎ㐣⛬࡟࠾ࡅࡿྠ఩యศูࡢ᳨ウࡣṧࡉࢀ࡚ࣂࣝࢡ DOC ⃰ᗘ࡟༨ࡵࡿ๭ྜࡣࠊ୕⏬ศࡢ୰࡛୰㛫࠸ࡿࡶࡢࡢࠊࣈ࣮࣒ࣝࡀ㏆ᖺほ࡛࠶ࡾࠊᮏ◊✲࡛⏝࠸ࡓ⍇⍈†⾲ᒙ†Ỉ࡛ࡣ 31%ࠊ㔝†Ỉ RPOC ࡢ㉳※࡜ࡋ࡚ࡣ㔜せࡔࡀࠊ†Ỉ LDOC ࡜†ỈὪᕝἙᕝỈ࡛ࡣ 24%ࡔࡗࡓࠋ

RDOC ࡢ㉳※࡜ࡋ࡚ࡣᐤ୚ࡀᑠࡉ࠸ྍ⬟ᛶࡀ♧၀ࡉࢀࡓࠋ

࡛ࡁࡓࠋ⍇⍈††Ỉࡢࡉࢀ࡚࠸ࡿ኱ᆺ⥳⸴ࡣࠊճ పศᏊ RDOC㸸㔜㔞ᖹᆒศᏊ㔞ࡣ 1300 ⛬ᗘ࡛ࠊపศ

†Ỉ LDOC ࡜†Ỉ RDOC ࡢ㉳※࡜ࡋ࡚ࡣࠊ୰ᑠᆺ᳜≀ࣉᏊ SLDOC ࡜࡯ࡰኚࢃࡽ࡞࠸ࠋᮏ◊✲ࡢᐇ㦂ࡢ᫬㛫ࢫࣛࣥࢡࢺࣥ⏤᮶ࡢ᭷ᶵ≀ࡀ㔜せࡔ࡜⪃࠼ࡽࢀࡿࠋࡘࡲࡾࠊ

ࢣ࣮ࣝ㸦200㹼400 ᪥㸧࡛ࡣศゎࡉࢀ࡞࠸㞴ศゎᛶᡂศ኱ᆺ⥳⸴⏤᮶ࡢ᭷ᶵ≀ࡣࠊ኱㒊ศࡣ†⾲ᒙ࡟ࡣṧࡽࡎࠊ࡛࠶ࡿࠋࣂࣝࢡ DOC ⃰ᗘ࡟༨ࡵࡿ๭ྜࡣࠊ୕⏬ศࡢ

POC ࡜ࡋ࡚†῝Ỉᒙ࡬࡜ỿ㝆ࡍࡿࢣ࣮ࢫࡀቑ࠼࡚࠸ࡿࡇ

୰࡛᭱ࡶ኱ࡁࡃࠊᮏ◊✲࡛⏝࠸ࡓ⍇⍈†⾲ᒙ†Ỉ࡛ࡣ࡜ࡀண᝿ࡉࢀࡿࠋࡇࡢࣉࣟࢭࢫࡣࠊ†ࡢᰤ㣴ሷືែࡸᗏᒙ

58%ࠊ㔝ὪᕝἙᕝỈ࡛ࡣ 68%ࡔࡗࡓࠋ⁐Ꮡ㓟⣲⃰ᗘ࡟኱ࡁ࡞ᙳ㡪ࢆ୚࠼࡚࠸ࡿྍ⬟ᛶࡀ࠶ࡾࠊ௒

ᮏ◊✲ࡢ⤖ᯝࡣࠊỈᅪ⎔ቃ DOC ࡟㛵ࡍࡿࢧ࢖ࢬ཯ᛂᛶ

ᚋࡢ◊✲࡛ᐇែࡸᙳ㡪ࡢホ౯ࢆ㐍ࡵ࡚࠸ࡃᚲせࡀ࠶ࡿࠋ㐃⥆యࣔࢹࣝ㸦Amon & Benner, 1996㸧࡟ᑐࡋ࡚ࠊᩚྜⓗ࡞᭷ᶵ≀ࡢ㛗ᮇ⏕ศゎヨ㦂ヨᩱࡢศᏊࢧ࢖ࢬศᯒ࠿ࡽࡣࠊ

㒊ศ࡜ࡑ࠺࡛࡞࠸㒊ศࡢ୧⪅ࢆྵࡴࠋ(1)㧗ศᏊ DOC ࡢศ⍇⍈††Ỉ࡜㔝ὪᕝἙᕝỈ࡟ࡘ࠸࡚ࠊDOC ࡢศᏊࢧ࢖ࢬ

ゎ㏿ᗘᐃᩘࡀపศᏊ SLDOC ࡼࡾࡶ㧗࠿ࡗࡓࡇ࡜ࠊ(2)100࡜⏕ศゎᛶࡢ㛵ಀࢆゎ᫂ࡋࡓࠋศᏊࢧ࢖ࢬ࡜⏕ศゎᛶ࡟ᇶ᪥௨ୖࡢ᫬㛫ࢫࢣ࣮࡛ࣝࡢ RDOC ࡀ඲࡚పศᏊ DOC ࡔ࡙ࡁࠊ†Ỉ࣭ἙᕝỈࡢ DOC ࡣࠊ୕⏬ศ㸦ձ㧗ศᏊ DOCࠊࡗࡓࡇ࡜ࡣࠊࡑࢀࡒࢀࢧ࢖ࢬ཯ᛂᛶ㐃⥆యࣔࢹࣝ࡜ᩚྜⓗղపศᏊ SLDOCࠊճపศᏊ RDOC㸧ࡢΰྜ࡜ࡋ࡚㏆ఝ࡛ࡔࡗࡓࠋ୍᪉࡛ࠊపศᏊ SLDOC ࡜పศᏊ RDOC ࡢ㔜㔞ᖹࡁࡿࡇ࡜ࡀ♧ࡉࢀࡓࠋ௒ᚋࠊDOC ࡢ⏕ศゎᛶࢆ㎿㏿࡟ᢕᆒศᏊ㔞ࡣ࡯ࡰྠࡌࡔࡗࡓࡓࡵࠊపศᏊ DOC ࣆ࣮ࢡࡢ୰

ᥱ࡛ࡁࡿᣦᶆࡢ㛤Ⓨ࡟ྥࡅ࡚ࠊᵝࠎ࡞Ꮨ⠇࣭ᆅⅬ࣭Ỉ῝ࡢ࡛ࡣศᏊࢧ࢖ࢬ࡜⏕ศゎᛶࡀᑐᛂࡋ࡚࠸࡞࠸ࠋỈᅪ⎔ቃヨᩱ࡟ࡘ࠸࡚ྠᵝࡢ㛗ᮇ⏕ศゎヨ㦂ࢆ⾜࠺ࡇ࡜ࠊศᏊࢧ࢖

DOC ࡬ࡢࢧ࢖ࢬ཯ᛂᛶ㐃⥆యࣔࢹࣝࡢ㐺⏝ྍ⬟ᛶ࡜ࠊศࢬู࡟ DOC ໬Ꮫ⤌ᡂࢆゎ᫂ࡍࡿࡇ࡜ࡀ㔜せ࡟࡞ࡿࠋ⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮◊✲ሗ࿌᭩➨ 16 ྕ75 ⤖ㄽ

ࡋࠊ%2' ࡣ %2' ࡢ࠾ࡼࡑ  ಸ࡜࡞ࡿࡇ࡜࡞࡝ࠊ᭷ᶵ

ᮏ◊✲࡛ࡣࠊ†ෆࡢ᭷ᶵ≀཰ᨭ࡟╔┠ࡋࠊ᳜≀ࣉࣛࣥࢡ≀ࡢ⏕ศゎᛶࡢᣦᶆ࡜࡞ࡿࡇ࡜ࡀ᫂ࡽ࠿࡟࡞ࡗࡓࠋ

ࢺࣥ࡟ࡼࡿ⏕⏘ࡸ㣗≀㐃㙐ࢆ㏻ࡌࡓ≀㉁ᚠ⎔ࡢ≧ἣࢆヲ

ࡑࡢ௚ࠊ32& ࡢⅣ⣲Ᏻᐃྠ఩యẚࡣ 32& ࡢ⏕ศゎᛶ⣽࡟ᢕᥱࡋࡓࠋࡲࡓࠊ†἟ࡢ೺඲ᛶࢆࠕ≀㉁ᚠ⎔ࡢ෇⁥ࡉࠖࡢᣦᶆ࡜ࡋ࡚᭷⏝࡞ྍ⬟ᛶࡀ࠶ࡿࡇ࡜ࠊ'20 ࡢศᏊࢧ࠿ࡽᐃ⩏ࡋࠊࡑࢀࢆホ౯ࡍࡿᣦᶆࢆᥦ᱌ࡍࡿ࡜࡜ࡶ࡟ࠊࣔ

࢖ࢬࡀ᭷ᶵ≀ࡢศゎᛶ࡜኱ࡁࡃ㛵㐃ࡍࡿࡇ࡜࠿ࡽࠊ

ࢹࣝࢆ⏝࠸ࡓゎᯒࡸ⌧ሙㄪᰝ࣭ศᯒࢆ⾜ࡗࡓࠋࡑࡢ⤖ᯝࠊ㧗ศᏊ '20 ࡜పศᏊ '20 ࡢ⃰ᗘẚ➼ࡀ '20 ࡢ⏕ศゎ୺࡟௨ୗࡢࡇ࡜ࡀ᫂ࡽ࠿࡟࡞ࡗࡓࠋ

ᛶࡢᣦᶆ࡜ࡋ࡚᭷⏝࡞ྍ⬟ᛶࡀ࠶ࡿࡇ࡜ࡀ᫂ࡽ࠿࡟

ձ

࡞ࡗࡓࠋ

ղ

⏕㣗㣗≀㐃㙐࡜ᚤ⏕≀㣗≀㐃㙐ࡢᐤ୚࡟ࡘ࠸࡚ㄪ࡭
ࡓ࡜ࡇࢁࠊᰤ㣴ሷࡢ㈇Ⲵ㔞ࡀῶᑡࡋࡓ⍇⍈†࡛ࡶࠊ ᖺ௦࡟ධࡗ࡚࠿ࡽࡣࠊ࣑ࢡࣛࢫࢸࣜ࢔ࢫࡸࢫࢱ࢘

㨶ࡢ㣵࡜࡞ࡿື≀ࣉࣛࣥࢡࢺࣥࡣࠊᰤ㣴ሷ࡛ቑ࠼ࡿ

ࣛࢫࢺ࣒ࣝ࡟௦⾲ࡉࢀࡿ኱ᆺ⸴㢮ࡀ኱㔞ቑṪࡍࡿ᫬ᮇࡀ

᳜≀ࣉࣛࣥࢡࢺࣥࢆ୺࡟㣗࡭࡚࠾ࡾࠊ᭷ᶵ≀࡛ቑ࠼

㢖Ⓨࡋ࡚࠾ࡾࠊỈ㉁⟶⌮ࡸ㨶௓㢮➼࡬ࡢ≀㉁ᚠ⎔ࡢほⅬ࠿ࡿᚤ⏕≀ࡣࢃࡎ࠿ࡋ࠿㣗࡭࡚࠸࡞࠿ࡗࡓࠋࡼࡗ࡚ࠊࡽၥ㢟どࡉࢀ࡚࠸ࡿࠋᮏ◊✲࡛᫂ࡽ࠿࡟ࡋࡓࡼ࠺࡟ࠊࡇࢀ

㨶࡬ࡢ≀㉁ఏ㐩㸦㣵࡜ᾘ㈝⪅ࡢ㛵ಀ㸧࡜ࡋ࡚ࡣࠊ⏕㣗ࡽࡢ኱ᆺ⸴㢮࡛ࡣ࡞ࡃ୰ᑠᆺࡢ᳜≀ࣉࣛࣥࢡࢺࣥࡀ⏕ࡳ㣗≀㐃㙐ࡢ᪉ࡀᚤ⏕≀㣗≀㐃㙐ࡼࡾࡶ㔜せ࡛࠶ࡿࡇฟࡉࢀࡿ⎔ቃࢆᙧᡂ࡛ࡁࢀࡤࠊỈ㉁ಖ඲࡜⏕≀⏕⏘ࡢ୧❧࡜ࡀ᫂ࡽ࠿࡟࡞ࡗࡓࠋ

࡟ࡘ࡞ࡀࡿࡇ࡜ࡀᮇᚅࡉࢀࡿࠋ௒ᚋࠊ୰ᑠᆺࡢ᳜≀ࣉࣛࣥⅣ⣲࣭❅⣲Ᏻᐃྠ఩యẚศᯒࡢ⤖ᯝ࠿ࡽࠊື≀ࣉࣛࢡࢺࣥࡢቑṪ࡟╔║ࡋࠊ†ෆ࡟࠾ࡅࡿ᭷ᶵ≀࠾ࡼࡧᰤ㣴ሷࣥࢡࢺࣥࡣࠊ᳜≀ࣉࣛࣥࢡࢺࣥࡢ୰࡛ࡶ୰ᑠᆺ㸦ࡢ෇⁥࡞ᚠ⎔࡟ࡘ࡞ࡀࡿせ௳ࢆ᫂ࡽ࠿࡟ࡍࡿ࡜࡜ࡶ࡟ࠊὶȣP ᮍ‶㸧ࡢࡶࡢࢆ୺㣗࡟ࡋ࡚࠾ࡾࠊ኱ᆺ㸦ȣP ௨ᇦᑐ⟇ࡢ࠶ࡾ᪉ࢆᥦ᱌ࡋ࡚࠸ࡃࡇ࡜ࡀᚲせ࡛࠶ࡿࠋ

ୖ㸧ࡢࡶࡢࡣ࡯࡜ࢇ࡝㣗࡭࡞࠸ࡇ࡜ࢆ☜ㄆࡋࡓࠋᐇ
㝿ࠊ኱ᆺ⸴㢮ࡀ኱Ⓨ⏕ࡋࡓ᫬ᮇ࡟ࡣࠊᩘ✀ࡢື≀ࣉ

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 ㅰ㎡

ࣛࣥࢡࢺࣥࡢ⌧Ꮡ㔞ࡸ⏕⏘㔞ࡀపࡃ࡞ࡿഴྥࡀ࠶ࡗ

⁠㈡┴ࠕ⍇⍈†࡟࠾ࡅࡿ᪂ࡓ࡞Ỉ㉁⟶⌮ࡢ࠶ࡾ᪉᠓ヰࡓࠋࡼࡗ࡚ࠊື≀ࣉࣛࣥࢡࢺࣥࢆቑࡸࡍࡓࡵ࡟ࡣࠊ㧗఍ࠖࠊ⎔ቃ◊✲⥲ྜ᥎㐍㈝ ࠕ⍇⍈†࡟࠾ࡅࡿ᭷ᶵ≀࠸ቑṪ㏿ᗘࢆᣢࡘ୰ᑠࢧ࢖ࢬࡢ᳜≀ࣉࣛࣥࢡࢺࣥࡀ

཰ᨭࡢᢕᥱ࡟㛵ࡍࡿ◊✲ࠖࢆ㏻ࡌ࡚ࠊᮏㄢ㢟࡟ࡘ࠸࡚ࡈព

ቑ࠼ࡸࡍ࠸⎔ቃ࡙ࡃࡾࡀᚲせ࡜⪃࠼ࡽࢀࡓࠋ

ぢࢆ࠸ࡓࡔ࠸ࡓ௨ୗࡢ᪉ࠎ㸦ᩗ⛠␎ 㡰୙ྠ㸧࡟ឤㅰࡍࡿࠋ

ࠕ†἟ࡢ೺඲ᛶࠖࢆホ౯ࡍࡿୖ࡛ࠕ†἟ෆ࡛ࡢ≀㉁ὠ㔝ὒࠊΎỈⰾஂࠊ⏣୰ᏹ᫂ࠊ㧗ᮧ඾Ꮚࠊ㏆⸨❳஧ࠊᑠ㔝ᚠ⎔ࡀ෇⁥࡛࠶ࡿࡇ࡜ࠖ࡟╔┠ࡋࠊ≀㉁ᚠ⎔ࡢ෇⁥㞞ྖࠊᑠᯇ┤ᶞࠊ୕࿴ఙᙪࠊዟ⏣୍⮧ࠊ⏣௰㍤Ꮚࠊ⁠㈡┴ࡉࢆ⾲ࡍ௨ୗ  ࡘࡢᣦᶆࢆᥦ᱌ࡋࡓࠋࡍ࡞ࢃࡕࠊձ

⍇⍈†⎔ቃ㒊ࡢⓙᵝࠊ⎔ቃ┬Ỉ࣭኱Ẽ⎔ቃᒁỈ⎔ቃㄢࡢⓙࠕ㐣୙㊊ࡀ࡞࠸ࠖ
㸸࿧྾ຠ⋡㸦㸻⩌㞟⥲࿧྾㔞㸭୍ḟ

ᵝࠋ

⏕⏘㔞➼㸧
ࠊղࠕ⁫ࡾࡀ࡞࠸ࠖ㸸㌿᥮ຠ⋡㸦㸻஧ḟ⏕⏘ᮏ◊✲ࡢ୍㒊ࡣࠊ⎔ቃ◊✲⥲ྜ᥎㐍㈝ ࠕ⍇⍈†࡟㔞㸭୍ḟ⏕⏘㔞➼㸧ࠊճࠕ೫ࡾࡀ࡞࠸ࠖ
㸸⏕≀ࣂࣛࣥࢫ

࠾ࡅࡿ᭷ᶵ≀཰ᨭࡢᢕᥱ࡟㛵ࡍࡿ◊✲ࠖࠊ࠾ࡼࡧி㒔኱Ꮫ㸦㸻㨶㢮ࣂ࢖࣐࢜ࢫ㸭᳜≀ࣉࣛࣥࢡࢺࣥࣂ࢖࣐࢜ࢫ㸧⏕ែᏛ◊✲ࢭࣥࢱ࣮ࡢඹྠ฼⏝࣭ඹྠ◊✲஦ᴗࠕ㹼࡛࠶ࡿࠋ ᖺᗘඹྠ◊✲ E㸸⏕ែ⣔ಖ඲࡟ࡘ࡞ࡀࡿ≀㉁ᚠ⎔ࡢ࠶㣗≀㐃㙐ࣔࢹࣝࢆ⏝࠸ࡓ⤖ᯝ࠿ࡽࠊᰤ㣴ሷࡢ⃰ᗘࡸࡾ᪉࡟㛵ࡍࡿ◊✲ࠖࡢᨭ᥼࡟ࡼࡾ⾜ࢃࢀࡓࠋ

᳜≀ࣉࣛࣥࢡࢺࣥ㔞࡜㨶㢮ࣂ࢖࣐࢜ࢫࡢ㛵ಀࡣ᫂☜࡛ࡣ࡞࠿ࡗࡓ୍᪉࡛ࠊ㌿᥮ຠ⋡࡜⏕≀ࣂࣛࣥࢫࡢ㛫 ᘬ⏝ᩥ⊩࡟᭷ព࡞┦㛵ࡀࡳࡽࢀࡓࠋࡇࢀࡼࡾࠊື≀ࣉࣛࣥࢡ㸦➨ 1 ❶㸧ࢺࣥࡸࣉࣛࣥࢡࢺࣥ㣗ᛶ㨶࡟㣗࡭ࡽࢀࡸࡍ࠸㣵⏕≀⁠㈡┴࣭ி㒔ᗓ㸦2017㸧㸸➨㸵ᮇ⍇⍈†࡟ಀࡿ†἟Ỉ㉁ಖ

ࡀᏑᅾࡍࡿࡇ࡜ࡀࠊࠕỈࡀࡁࢀ࠸࡛㨶ࡀ㇏࠿࡛࠶ࡿࠖ

඲ィ⏬㸬⎔ቃࡢࡓࡵ࡟㔜せ࡛࠶ࡿ࡜⪃࠼ࡽࢀࡓࠋ
յ⍇⍈††Ỉࡢ⏕ศゎヨ㦂ࡸ δ13C ್ࡢ⤒ᖺ࣭Ꮨ⠇ኚື

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㸦➨ 2 ❶㸧ࡉࢀ࡚࠸ࡿ኱ᆺ⥳⸴ࡣࠊ†Ỉ DOC

Costanza, R. (1992): Toward an operational definition ofࡢ㉳※࡜ࡋ࡚ࡣᐤ୚ࡀᑠࡉࡃࠊ኱㒊ศࡣ POC ࡜ࡋ࡚

ecosystem health. Ecosystem health, New goals for†῝Ỉᒙ࡬࡜ỿ㝆ࡋ࡚࠸ࡿࡇ࡜ࡀ♧၀ࡉࢀࡓࠋ

environmental management, 239-256.

࠿ࡽࡣࠊ㏆ᖺほ᭷ᶵ≀ࡢศゎᛶ㸦᫆ศゎᛶ᭷ᶵ≀ࡢ㔞㸧ࢆホ౯ࡍࡿబ⸨♸୍࣭ᑠᯇⱥྖ࣭Ọ⚰ⱥ࣭᫂ୖཎᾈ࣭‫‮‬ὸᓅྐ࣭኱ஂ

ᡭἲ࡜ࡋ࡚ࠊ%2' ࡢᇵ㣴ᮇ㛫ࢆ  ᪥㛫㸦%2'㸧࡟ᘏಖ༟ஓ࣭ᒸᮏ㧗ᘯ࣭㔠෌ዋ㸦2011㸧㸸㝣ᇦ㸫†ෆὶື㸫㛗ࡍࡿࡇ࡜࡟ࡼࡗ࡚⢭ᗘⰋࡃ†ෆ⏕ែ⣔ࢆ⤖ྜࡋࡓ⍇⍈†ὶᇦỈ≀㉁ᚠ⎔ࣔࢹࣝࡢᐃࡍࡿࡇ࡜ࢆྍ⬟࡜

⁠㈡┴⍇⍈†⎔ቃ⛉Ꮫ◊✲ࢭࣥࢱ࣮ヨ㦂◊✲ሗ࿌᭩➨ 16 ྕᵓ⠏࡜ࡑࡢ᳨ド㸪Ỉ⎔ቃᏛ఍ㄅ㸪34㸦9㸧
㸪125-141㸬

Analusis of long-term variation in phytoplankton biovolumeబ⸨♸୍࣭᪩ᕝ࿴⚽㸦2019a㸧
㸸ࠕ≀㉁ᚠ⎔ࡢ෇⁥ࡉࠖࢆᣦin the northern basin of Lake Biwa. Limnology, 14㸸117-128.

ᶆ࡜ࡋࡓ᪂ࡓ࡞ὶධ㈇Ⲵ⟶⌮ࡢ᪉ྥᛶ㸪➨ 22 ᅇ᪥ᮏỈ

Logan, J. M., T. D. Jardine, T. J. Miller, S. E. Bunn, R. A. Cunjak⎔ቃᏛ఍ࢩ࣏ࣥࢪ࣒࢘ㅮ₇㞟㸪194-195㸬

and M. E. Lutcavage㸦2008㸧
㸸Lipid corrections in carbon andబ⸨♸୍࣭᪩ᕝ࿴⚽㸦2019b㸧㸸ᰤ㣴ሷ㈇Ⲵࡢቑῶࡀ⍇⍈†nitrogen stable isotope analyses: comparison of chemicalࡢ㧗ḟ⏕ែ⣔࡟୚࠼ࡿᙳ㡪㸸ࣔࣥࢸ࢝ࣝࣟἲࢆ⏝࠸ࡓ㣗

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㸸ࠕỈࡢࡁࢀ࠸
ࡉࠖ࡜ࠕ㨶ࡢ㇏࠿ࡉࠖࡣ୧❧࡛ࡁࡿࡢ࠿㸽⍇⍈†࡟࠾ࡅࡿ㣗≀㐃㙐ࣔࢹࣝࢆ⏝࠸ࡓゎᯒ㸪➨ 53 ᅇ᪥ᮏỈ⎔ቃᏛ

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