1995 Fiscal Year Final Research Report Summary
Dendrochronological assessment for air pollution using stumps of Cryptomeria japonica (Sugi)
| Project/Area Number |
06680500
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
環境影響評価(含放射線生物学)
|
|---|
| Research Institution | TOYAMA MEDICAL AND PHARMACEUTICAL UNIVERSITY |
|---|
Principal Investigator |
KATOH Terutaka Toyama Medical and Pharmaceutical University Faculty of Medicine, Research Associate, 医学部・公衆衛生学, 助手 (80115162)
|
|---|
| Project Period (FY) |
1994 – 1995
|
| Keywords | Dendrochronology / Tree ring-width / Standardized ring index / Sugi / Cryptomeria japonica / Stump / Air pollution / Sulfur oxides |
|---|
| Research Abstract |
A total of 20 cores were collected from the stumps of Cryptomeria japonica growing in Toyama Prefecture. After polishing the cores, the ring-widths were measured to the nearest 0.01 mm using a dliding linear table (LINTAB). This instrument was interfaced with an IBM-compatible personal computer and the data were analyzed by a time series analysis program (TSAP-X). Specimens those taken by another research projects were also incorporated in this study. The results were as follows.
(1) After removing the effects of tree age and climatic conditions the impacts of air pollutants on increment growth in Cryptomeria japonica was analyzed. During the period of the late '60s to the early '70s, when serious air pollution was recorded, decreased increment growth was observed. Since the mid '70s increased increment growth in Cryptomeria japonica was observed with decreasing levels of air pollutants.
(2) The impact of three categories of air pollutants, i. e., sulfur oxides, nitrogen oxides and oxidants, on increment growth was studied by a multiple regression analysis. The levels of aulfur oxides were suggested to be the determining factor.
(3) In generally, a similar pattern in ring-width was observed with Cryptomeria japonica those growing in the plain area and the mountain area. This means that time series of the ring-width in these two areas are quite similar but large gaps are observed in some exceptional years. It is suggested that the large gap in special year has its origin in the heavy snowfall in plain area and/or unusual light snowfall in the mountain area.
|
