Table 1.
Variations in physical and chemical characteristics in ten cruises.
| Jan-2018 | Apr-2018 | Jul-2018 | Oct-2018 | Jan-2019 | Apr-2019 | Jul-2019 | Apr-2020 | Oct-2020 | Dec-2020 | |
|---|---|---|---|---|---|---|---|---|---|---|
| WT (℃) |
13.08 ± 1.21 (12.2~15.8) | 20.12 ± 2.11 (17.9~24.8) | 31.40 ± 2.16 (29.8~37.6) | 20.88 ± 0.67 (20.1~21.8) | 12.76 ± 0.41 (12.4~13.6) | 17.32 ± 0.88 (16.4~19.5) | 30.36 ± 0.43 (29.8~31.5) | 18.33 ± 1.47 (17.3~22.6) | 24.68 ± 1.90 (23.6~28.8) | 19.87 ± 3.21 (16.0~24.7) |
| Sal (PSU) | 26.90 ± 0.15(26.65~27.25) | 29.46 ± 0.20(29.11~29.72) | 32.48 ± 0.22 (32.22~32.86) | 27.96 ± 0.32 (27.41~28.40) | 27.17 ± 0.20 (27.03~27.78) | 27.55 ± 0.16 (27.22~27.72) | 30.60 ± 0.16 (30.35~30.86) | 27.70 ± 0.14 (27.24~27.78) | 28.02 ± 0.37 (27.50~28.41) | 25.94 ± 0.04 (25.87~26.02) |
| pH | 8.04 ± 0.02 (8.00~8.06) | 8.13 ± 0.03 (8.08~8.17) | 8.15 ± 0.04 (8.10~8.22) | 7.99 ± 0.04 (7.94~8.06) | 8.10 ± 0.01 (8.08~8.11) | 8.07 ± 0.04 (8.03~8.14) | 8.13 ± 0.02 (8.10~8.16) | 8.11 ± 0.02 (8.07~8.13) | 8.12 ± 0.01 (8.10~8.13) | 8.11 ± 0.07 (7.97~8.20) |
| DO (μmol·L−1) |
9.09 ± 0.15 (8.81~9.30) | 8.09 ± 0.36 (7.50~8.60) | 7.52 ± 0.77 (6.36~8.65) | 7.17 ± 0.25 (6.73~7.46) | 8.82 ± 0.10 (8.64~8.94) | 7.88 ± 0.38 (7.40~8.58) | 5.81 ± 0.25 (5.53~6.37) | 7.86 ± 0.12 (7.73~8.14) | 7.23 ± 0.34 (6.38~7.84) | 6.84 ± 0.16 (6.54~7.17) |
| COD (mg·L−1) |
1.18 ± 0.26 (0.89~1.94) | 0.78 ± 0.11 (0.62~0.97) | 0.95 ± 0.24 (0.63~1.39) | 0.75 ± 0.25 (0.50~1.42) | 1.13 ± 0.26 (0.75~1.56) | 0.84 ± 0.32 (0.54~1.75) | 0.85 ± 0.20 (0.48~1.16) | 0.71 ± 0.10 (0.59~0.86) | 1.10 ± 0.32 (0.5~1.6) | 0.94 ± 0.47 (0.47~1.76) |
| PO4—P (nmol·L−1) | 0.026 ± 0.009(0.014~0.043) | 0.014 ± 0.004 (0.008~0.021) | 0.017 ± 0.004 (0.009~0.022) | 0.031 ± 0.011 (0.015~0.047) | 0.055 ± 0.010 (0.047~0.074) | 0.021 ± 0.008 (0.012~0.033) | 0.015 ± 0.002 (0.013~0.019) | 0.033 ± 0.001 (0.030~0.035) | 0.021 ± 0.003 (0.017~0.027) | 0.032 ± 0.006 (0.026~0.040) |
| NO2—N (nmol·L−1) | 0.007 ± 0.003 (0.003~0.017) | 0.007 ± 0.001 (0.005~0.009) | 0.010 ± 0.004 (0.001~0.017) | 0.008 ± 0.00 (0.005~0.01) | 0.005 ± 0.001 (0.004~0.006) | 0.008 ± 0.004 (0.003~0.014) | 0.017 ± 0.002 (0.015~0.020) | 0.016 ± 0.001 (0.014~0.018) | 0.010 ± 0.005 (0.006~0.018) | 0.008 ± 0.002 (0.006~0.013) |
| NO3—N (nmol·L−1) | 0.35 ± 0.11 (0.19~0.56) | 0.22 ± 0.06 (0.12~0.30) | 0.07 ± 0.02 (0.03~0.10) | 0.36 ± 0.14 (0.18~0.57) | 0.54 ± 0.02 (0.51~0.56) | 0.33 ± 0.1178 (0.18~0.48) | 0.10 ± 0.00 (0.09~0.12) | 0.52 ± 0.02 (0.48~0.55) | 0.23 ± 0.05 (0.15~0.31) | 0.61 ± 0.02 (0.59~0.64) |
| NH4—N (nmol·L−1) | 0.026 ± 0.014 (0.013~0.065) | 0.036 ± 0.035 (0.013~0.114) | 0.021 ± 0.006 (0.015~0.039) | 0.014 ± 0.004 (0.007~0.020) | 0.039 ± 0.016 (0.022~0.079) | 0.031 ± 0.013 (0.018~0.063) | 0.015 ± 0.005 (0.008~0.024) | 0.031 ± 0.009 (0.018~0.048) | 0.031 ± 0.017 (0.017~0.080) | 0.048 ± 0.016 (0.018~0.069) |
| DIN (nmol·L−1) | 0.39 ± 0.11 (0.21~0.60) | 0.27 ± 0.09 (0.16~0.27) | 0.10 ± 0.03 (0.05~0.15) | 0.38 ± 0.14 (0.19~0.60) | 0.59 ± 0.02 (0.56~0.65) | 0.37 ± 0.12 (0.21~0.52) | 0.13 ± 0.01 (0.11~0.16) | 0.57 ± 0.02 (0.52~0.59) | 0.27 ± 0.06 (0.19~0.39) | 0.67 ± 0.01 (0.63~0.69) |
| SiO4-Si (nmol·L−1) | 0.77 ± 0.25 (0.38~1.27) | 0.46 ± 0.11 (0.27~0.62) | 0.47 ± 0.09 (0.26~0.58) | 0.77 ± 0.34 (0.25~1.22) | 1.30 ± 0.03 (1.22~1.33) | 0.66 ± 0.025 (0.34~0.98) | 0.66 ± 0.06 (0.54~0.76) | NA | NA | NA |
| Chl-a (μg·L−1) | 0.45 ± 0.15 (0.24~0.68) | 5.82 ± 2.20 (1.36~9.00) | 3.03 ± 1.12 (1.17~5.67) | 0.81 ± 0.29 (0.44~1.56) | 0.61 ± 0.01 (0.46~0.77) | 1.37 ± 0.41 (0.56~2.24) | 5.69 ± 2.53 (1.8~10.33) | 0.93 ± 0.18 (0.68~1.15) | 5.02 ± 1.42 (2.73~6.62) | 1.03 ± 0.36 (0.65~1.56) |
| ss (mg·L−1) | 93.69 ± 20.39 (48.2~133.0) | 26.92 ± 12.89 (11.6~53.4) | 19.43 ± 6.03 (12.4~33.2) | 44.60 ± 12.65 (27.0~69.2) | 144.39 ± 38.42 (96.0~212.3) | 57.20 ± 27.779 (20.8~95.2) | 43.85 ± 12.81 (18.8~63.0) | 29.40 ± 9.21 (18.4~52.8) | 119.93 ± 100.3 (25.6~383.2) | 152.43 ± 173.1 (25.6~528.7) |
Table 1 shows the means and standard deviations of environmental parameters for each cruise. The numbers in brackets are the range in which the feature varies. NA means not analyzed; WT, Sal and ss stand for water temperature, salinity and suspended particulate composition, respectively.