CSEMP assessment of arsenic in sediment at Cosheston Point (Milford Haven)
Statistical analysis
Trend assessment
Analysis of variance
Df | AIC | AICc | Log lik | Deviance | Chisq | Chi df | Pr(>Chisq) | |
---|---|---|---|---|---|---|---|---|
mean | 1 | -83.35 | -81.97 | 44.68 | -89.35 | |||
linear | 2 | -91.14 | -88.47 | 49.57 | -99.14 | 9.787 | 1 | 0.0018 |
smooth (df = 2) | 3 | -94.56 | -90.02 | 52.28 | -104.56 | 5.422 | 1 | 0.0199 |
smooth (df = 3) | 4 | -93.46 | -86.26 | 52.73 | -105.46 | 0.896 | 1 | 0.3439 |
smooth (df = 4) | 5 | -98.41 | -87.52 | 56.21 | -112.41 | 6.955 | 1 | 0.0084 |
Change in log concentration
Year start | Year end | Fit start | Fit end | Change | Std error | t | Pr(>|t|) | |
---|---|---|---|---|---|---|---|---|
overall | 1999 | 2018 | 2.6704 | 3.1570 | 0.4866 | 0.0995 | 4.889 | 0.0003 |
last 20 years | 1999 | 2018 | 2.6704 | 3.1570 | 0.4866 | 0.0995 | 4.889 | 0.0003 |
Status assessment
Conc fitted | Conc ref | Log ratio | Std error | t | Pr(>t) | |
---|---|---|---|---|---|---|
BAC | 23.501 | 25.000 | 0.06185 | 0.08795 | 0.703 | 0.2471 |
Raw data with supporting information
Raw data with assessment
Assessment plot
Metals data
Metals assessment
Related pages
- Clean Seas Environment Monitoring Programme (CSEMP) accessment viewer tool
- Assessment methodology for metals in sediment
- Accessment criteria for metals in sediment
Media : Sediment (< 63 micron fraction)
Station : Severn_MilfordHav_se01, Cosheston Point (Milford Haven)
Determinand : Arsenic
Units : mg kg -1 dry weight normalised to 5% aluminium
Data extraction : 30 April 2020
Station : Severn_MilfordHav_se01, Cosheston Point (Milford Haven)
Determinand : Arsenic
Units : mg kg -1 dry weight normalised to 5% aluminium
Data extraction : 30 April 2020