A Conflict between the Legacy of Eutrophication and Cultural Oligotrophication in Hiroshima Bay
Abstract
:1. Introduction
2. Materials and Methods
2.1. Characteristics of Hiroshima Bay
2.2. Field Observations
2.3. Chemical Analyses
2.4. Estimation of the Sediment P Content
3. Results
3.1. Sediment C, N, S, and P Contents
3.2. Subsidiary Parameters Relating to C, N, S and P Cycles
4. Discussion
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Depth (cm) | TOC (mg C g dry−1) | TN (mg N g dry−1) | TS (mg S g dry−1) | TP (mg P g dry−1) | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Avg | Stdev | CV (%) | Avg | Stdev | CV (%) | Avg | Stdev | CV (%) | Avg | Stdev | CV (%) | |
2.5 | 15 | 3 | 17 | 1.6 | 0.5 | 32 | 3.9 | 1.4 | 35 | 0.57 | 0.04 | 6 |
7.5 | 14 | 3 | 21 | 1.4 | 0.4 | 31 | 3.9 | 1.3 | 32 | 0.52 | 0.04 | 9 |
12.5 | 14 | 3 | 24 | 1.2 | 0.4 | 33 | 4.1 | 1.7 | 41 | 0.50 | 0.06 | 11 |
17.5 | 13 | 3 | 25 | 1.2 | 0.4 | 35 | 3.7 | 1.6 | 43 | 0.46 | 0.03 | 6 |
25 | 12 | 4 | 30 | 1.2 | 0.4 | 36 | 3.6 | 1.3 | 37 | 0.46 | 0.04 | 8 |
Parameters | Area | Value Range |
---|---|---|
Eh (mV) | N | −150–−27 |
S | −153–+45 | |
WC (%) | N | 69.8–82.5 |
S | 46.6–81.8 | |
IL (%) | N | 10.9–12.7 |
S | 4.8–11.3 | |
AVS (mg g dw−1) | N | 0.17–1.14 |
S | 0.04–0.35 | |
H2S (mg L−1) | N | 0–19 |
S | 0–23 |
Year | TOC (mg g−1) | TN (mg g−1) | TP (mg g−1) | References | |
---|---|---|---|---|---|
1982 | Max | 30 | 3.5 | 0.75 | [54] |
Min | 9.6 | 1.0 | 0.34 | ||
Avg | 20 | 2.5 | 0.59 | ||
SD | 5.4 | 0.66 | 0.11 | ||
CV (%) | 27 | 27 | 18 | ||
1993 | Max | 26 | 2.8 | 0.62 | [55] |
Min | 2.8 | 0.36 | 0.26 | ||
Avg | 18 | 2.1 | 0.53 | ||
SD | 5.7 | 0.62 | 0.090 | ||
CV (%) | 32 | 30 | 17 | ||
2003 | Max | 29 | 3.1 | 0.68 | [56] |
Min | 4.4 | 0.60 | 0.20 | ||
Avg | 17 | 2.2 | 0.51 | ||
SD | 6.8 | 0.78 | 0.12 | ||
CV (%) | 39 | 36 | 23 | ||
Oct 2020 | Max | 21 | 3.0 | 0.66 | This study |
Min | 9.4 | 0.62 | 0.49 | ||
Avg | 15 | 1.6 | 0.57 | ||
SD | 2.6 | 0.50 | 0.040 | ||
CV (%) | 17 | 32 | 6 |
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Yamamoto, T.; Orimoto, K.; Asaoka, S.; Yamamoto, H.; Onodera, S.-i. A Conflict between the Legacy of Eutrophication and Cultural Oligotrophication in Hiroshima Bay. Oceans 2021, 2, 546-565. https://doi.org/10.3390/oceans2030031
Yamamoto T, Orimoto K, Asaoka S, Yamamoto H, Onodera S-i. A Conflict between the Legacy of Eutrophication and Cultural Oligotrophication in Hiroshima Bay. Oceans. 2021; 2(3):546-565. https://doi.org/10.3390/oceans2030031
Chicago/Turabian StyleYamamoto, Tamiji, Kaori Orimoto, Satoshi Asaoka, Hironori Yamamoto, and Shin-ichi Onodera. 2021. "A Conflict between the Legacy of Eutrophication and Cultural Oligotrophication in Hiroshima Bay" Oceans 2, no. 3: 546-565. https://doi.org/10.3390/oceans2030031