The Quaternary Research /+, p +*- ++/,*+, +,a, - * * * * * * * / 0 1 TOC TN +32* +3-* +30* +32* +33* : I +ob +30*,**/ ;,**2 +31-,**2 +312,**2,**2,**3 Nishikawa et al,*+* -/ Imai et al,,**0 +31-,**1 +30* 1* +310 -** +** Yamamoto,,**- +oa,* *,*++ +* /,*+,, ++ * + 03* 2/* +*0* *, 30* +,30 + * - 03* 2/* +*0* * 03 ***- ++,+ 2 */ 03* 2/* +*0* * 0 1--2/,+ 1 + * 1 12* 2/,*, / + * a Corresponding author : s ++31* @matsushimane-u ac jp
104 /+,,**-,oa +32*,o a,**0 II +312,** +31-,**-, -,0 km : BOD Cr,/43 m, - 223 m +33 BOD, : SS, TN,**1 +33 BOD +* + +33/ + mgl,**0 TN BOD -,**1 +32* +33*,**0 ;,*+* + a +3/*,**1 +3/* +333 :,**2 Yamamoto,**-,***,**1 :,**2 III b +31,**1,**2,**2 1 +*, HNA, HNB, HNAHNB + 2,**2
,*+, 105 + Pbo,+* Cso+-1 Peirson, +31+ ;,*** - g - g, g,+ Canberra EGPC+/* P+0 Canberra - BOD ver +40, Pbo,+* Pbo,+ Cso+-1 TN HNA HNA*+ -,,,**1 HNB HNB*+ -3,*,, CHN TOC,**3a TN CHN +* +/,o b mg + N HNA - /4/-0 + +-,041-/ 14/ m HNB - -403/ +-,24--3 +-40 m CHN MT/ HNB CHN,**2 Hao1, - Hao1, 0*, HNA, HNB,*++ -/4/ cm, -14/ cm,*** IV *4*+/ *4*,* g / -4* ml mm CHN -* *4, ml - +42 ml,4* ml *4/ ml HNA*+ 1+ HNB*+ 1/ +2 +2 mm CHN 0* : 1* - +* +**
106 /+, +* Q,** Web PAST http : folkuionoohammerpast ; Hammer et al, 1* +,**+ Horn +300 + HNA
,*+, 107 V + -,4/ gcm,**2 Hao1, mass depth +,, + cm, HNB
108 /+, HNAHNB a, c : Pbo,+* b, d : Cso+-1 HNB, + HNA Pbo,+* oc + Pbo,+* HNA, Bqg gcm o a, *4*3gcm Cso+-1 oa Pbo,+* od Cso+-1 ++4* ++4/ cm, *4+ gcm 3 +* cm +30- Cso+-1 ob Cso +-1 +24* +24/ cm, *4*2 gcm Peirson +31+ Cso+-1, +30- HNB +-4* +4* cm +30-, HNA *4+- gcm,**2 Cso+-1 +120,**2 CHN + HNA Pbo,+* Cso+-1, CHN Pbo,+* + HNA Cso+-1 TOC +4*0 +23* +22-,**2 +43/,**2 TOC +22* +3,* +4+*, HNB +3-*
,*+, 109 / HNAHNB TOCTN +32* +33* Cyclotella N pelagica, S costatum, T TN nitzschioides, Thalassiosira TOC +23*,**2,*** Chaetoceros TN +22* +3-* *4+, /oa Chaetoceros, HNB TOC +4+/ +2** Chaetoceros +43/,*** TOC +3-* +4+ +4, C weissflogii, D aestuarii, N panduriformis, P sulcata +3-*,*** TN P sulcata *4+ +2/* *4,0,*** TN +3-* *4+ *4+0 TOC,**3 /ob + HNA 0oa, c - 0 +3-* +*4* +* valvesg HNA 1 HNB 0 Chaetoceros Cyclotella Cymatotheca Thalassiosira weissflogii, Diploneis aestuarii, Neodelphineis pelagica, + g Nitzschia panduriformis, Paralia sulcata, Skeletonema +3-* costatum, Thalassionema nitzschioides, Thalassiosira Chaetoceros Chaetoceros +3-* - +32* +33* HNAHNB 0 P sulcata +3-*, +30*
110 /+, +33* P sulcata Q N pelagica +30* +3* AL +3* +33* 0 HNAHNB a, b c, d
,*+, 111 AM, +33*,**2 AU AL AM AM AU N pelagica N pelagica,, HNB 0ob, d 0 +3-*,*4* +* valvesg HNB HNA Chaetoceros +32* +3-* P sulcata * /*,**0 ;,**0 ;,*+* +3-* N pelagica +3/* +32* + +3-* +30* 1* TOC Chaetoceros +33* TN Q +32* BL +32*,**2 P sulcata BU BU N pelagica Chaetoceros BL,,**3 +3/* +3* P sulcata, C weissflogii BL, +3* +3/* +32* N pelagica BU BL, BL+ VI + +31- Katsuki et al,,**3 Nishikawa et al,*+* 2* 3* Skeletonema spp Chaetoceros spp P sulcata Chae- Katsuki et al,,**3 +3-* toceros spp Skeletonema spp Chaetoceros, +3-* +30*,**3 +3-* HNA
112 /+, HNA TOCTN,**2 HNB,**2 HNA HNB +32* :COD +32* 3* HNA Chaetoceros,**3b TOC Chaetoceros +332 14/ m m HNB,**2 HNB TOC HNA +-40 m HNA HNB +3-* HNA HNB HNA HNB HNB Chaetoceros / +33* : +3-* +30* HNA Chaetoceros +33* TOC +33* +33*,**0 ; - +30* +31* :,*+* +311 +30* +31* HNA HNB HNA TOC P sulcata,**2 Chaetoceros P sulcata,**/ ;,**2 ; Katsuki et al,,**3 +33* HNB Chaetoceros
,*+, 113 Diatom,,/,+ -0,**2 +,* 1,21,30,**3 1 COD ++0,oa,**2 +10,*++,**2,*++ +2 COD +32+ +33*,4/ mgl 0 +33+ +4/ mgl 1 Horn, HS ( +300) Measurement of overlap in comparative ecological studies American Naturalist, +**, +3, - HNB,**1 Chaetoceros http : webprefhyogo jpch* ch *_ + _*******,3html,*++ 0 -,**2 no 13 +* +1 Imai, I, Yamaguchi, M and Hori, Y (,**0) Eutrophication and occurrences of harmful algal blooms in the Seto Inland Sea, Japan Plankton & Benthos Research, +, 1+ 2,**3a no,2 + 3,**3b,**3,+-*+1- : 1*,*** Hammer,, Harper, DAT and Ryan, PD (,**+) no, 01 +-* PAST : Paleontological statistics software package,***,+* for education and data Analysis Palaeontologia -,--3 Electronica,, 3p, http : palaeo-electronicaorg Katsuki, K, Seto, K, Nomura, R, Maekawa, K and,**+_ + pastissue + _*+html Khim, B (,**3) E# ect of human activity on Lake,**3 Saroma (Japan) during the past +/* years : Evi-
114 /+, dence by variation of diatom assemblage Estuar- ture,,-, 132* ine, Coastal and Shelf Science, 2+,,+/,,,**-,**0 +03 p,**2 +3 no, 1, 2* +311 ++3 p,**2 - +01 +1+ http : wwwjfama #gojpsetouti,**0 akasionenkanindexhtml,*++ 3 + Yamamoto, T (,**-) The Seto Inland Seaeutrophic no -3 +1,, or oligotrophic? Marine Pollution Bulletin, 1, -1,,**/,**2 +-* p,2 --3-/ Nishikawa, T, Hori, Y, Nagai, S, Miyahara, K, Nakamura,,*+* Y, Harada, K, Tanda, M, Manabe, T and Tada, K (,*+*) Nutrient and phytoplankton dynamics in Harima-Nada, eastern Seto Inland Sea, Japan during a -/-year period from +31- to,**1 +-2-1-3,*** : : / /* Estuaries and Coasts, --, +1,1,**/ +** Peirson, DH ( +31+ ) Worldwide deposition of long- ++ +,* lived fission products from nuclear explosions Na-
,*+, 115 Spatio-temporal changes of diatom assemblages and marine environments over the past few hundread years in coastal areas of northern Harima-Nada, Hyougo Prefecture, southwestern Japan +,a, - Kaoru Yoshioka*, Kotaro Hirose*, Toshiaki Irizuki*, / Shigenori Kawano*, Ritsuo Nomura*, Asumi Gotomyo* and Masao Iwai* 0 1,+* +-1 Pb and Cs age dating, total organic car- curred earlier than the initiation of the high bon (TOC) and total nitrogen (TN) contents economic growth period, and diatoms flouanalysis, and diatom analysis were conducted rished during the +3* s+30* s Deterioration of in sediment samples from two short cores collected marine environments peaked in the +30* s+31* s from Sakoshi Bay (core HNA) and o# In the +32* s, Sakoshi Bay and a site o# Aioi Aioi City (core HNB), northern Harima-Nada, City underwent di# erent paleoenvironmental,+* +-1 southwest Japan The results of Pb and Cs changes Since the +33* s, water and bottom dating shows that ages at the bottom of core environments in Sakoshi Bay were deterio- HNA and that of core HNB were estimated at rated by oyster farming, while water environments +22- AD and +120AD, respectively Spatio-temporal o# Aioi City were influenced by the im- changes of diatom assemblages and TOC and provement of water quality in northern Harima- TN contents were as follows : In coastal areas Nada of northern Harima-Nada, eutrophication oc- Keywords : diatom assemblages, anthropogenic pollution, oyster farmings, Ibo River, Harima- Nada * + Department of Materials Creation and Circulation Technology, Interdisciplinary Graduate School of Science and Engineering, Shimane University +*0* Nishikawatsu-cho, Matsue, 03* 2/*, Japan *, Graduate School of Symbiotic Systems Science and Technology, Fukushima University + Kanayagawa, Fukushima, 30* +,30, Japan * - Dpartment of Earth Sciences, Interdisciplinary Faculty of Science and Engineering, Shimane University +*0* Nishikawatsu-cho, Matsue, 03* 2/*, Japan * The Shimane Nature Museum of Mt Sanbe ++,+ 2 Tane, Sanbe-cho, Ooda, 03 ***-, Japan * / Faculty of Education, Shimane University +*0* Nishikawatsu-cho, Matsue, 03* 2/*, Japan * 0 Daiichi Gakushusha Corporation 1 + Yokogawashin-machi, Nishi-ku, Hiroshima, 1--2/,+, Japan * 1 Faculty of Science, Kochi University, / + Akebono-cho, Kochi, 12* 2/,*, Japan * a Corresponding author : s ++31* @matsushimane-u ac jp