Developing a Sentinel Monitoring Network for Scotland's Rivers And
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CR/2016/07 Developing a sentinel monitoring network for Scotland’s rivers and lochs Daniel Chapman, Laurence Carvalho, Iain Gunn, Linda May, Mike Bowes, Matthew O’Hare NERC Centre for Ecology & Hydrology 27 th February 2018 Contents Executive summary ................................................................................................................................. 5 Introduction ........................................................................................................................................... 10 1. Representativeness of the existing river surveillance network ............................................................. 12 Summary ........................................................................................................................................... 12 Introduction and aims ........................................................................................................................ 12 Methods ............................................................................................................................................ 13 Data ............................................................................................................................................... 13 Representativeness with respect to individual gradients .................................................................. 18 Representativeness with respect to all gradients ............................................................................. 18 Results .............................................................................................................................................. 19 Discussion and conclusions ............................................................................................................... 22 2. Designing a more representative and efficient river sentinel network .................................................. 23 Summary ........................................................................................................................................... 23 Introduction and aims ........................................................................................................................ 23 Methods ............................................................................................................................................ 24 Results .............................................................................................................................................. 25 Discussion and conclusions ............................................................................................................... 30 3. Power of the river and loch sentinel networks to detect change .......................................................... 32 1 Summary ........................................................................................................................................... 32 Introduction and aims ........................................................................................................................ 33 Methods ............................................................................................................................................ 34 Overview ....................................................................................................................................... 34 Trend models ................................................................................................................................. 34 Minimum detectable trends in the current monitoring data ............................................................. 38 Power of modified sampling regimes to detect trends in the river surveillance network .................. 39 Results .............................................................................................................................................. 41 Trend models ................................................................................................................................. 41 Minimum detectable trends in the current monitoring data ............................................................. 42 Power of modified sampling regimes to detect trends in the river surveillance network .................. 49 Discussion and conclusions ............................................................................................................... 53 4. Long-term changes detectable in the existing river and loch sentinel networks ................................... 56 Summary ........................................................................................................................................... 56 Introduction and aims ........................................................................................................................ 56 Methods ............................................................................................................................................ 57 Overview ....................................................................................................................................... 57 Linear trend models ....................................................................................................................... 57 Nonlinear trend models .................................................................................................................. 58 Results .............................................................................................................................................. 59 Linear trend models ....................................................................................................................... 59 Nonlinear trend models .................................................................................................................. 62 Discussion and conclusions ............................................................................................................... 66 5. Review of innovative monitoring methods ......................................................................................... 69 Summary ........................................................................................................................................... 69 Introduction ....................................................................................................................................... 69 Purpose .......................................................................................................................................... 69 2 Background ................................................................................................................................... 69 Approach ....................................................................................................................................... 70 Report Structure ............................................................................................................................. 70 Findings ............................................................................................................................................ 72 eDNA application to monitoring in Scotland .................................................................................. 72 Rivers – general monitoring review ................................................................................................ 73 Lochs – general monitoring review ................................................................................................ 75 General observations ......................................................................................................................... 76 Future challenges for surveillance networks ................................................................................... 76 References ............................................................................................................................................. 78 Appendices ........................................................................................................................................... 88 Appendix 2.1: Priority water bodies for removal from the river surveillance network ............................. 88 Appendix 2.2: Priority water bodies for addition to the river surveillance network ................................. 96 Appendix 2.3 R code to analyse and improve the representativeness of a monitoring network ................ 99 R Functions ....................................................................................................................................... 99 Example workflow .......................................................................................................................... 103 Appendix 3.1 R code to run power analysis ......................................................................................... 105 R function ....................................................................................................................................... 105 Example workflow .......................................................................................................................... 106 Appendix 5.1: Detailed review of innovative monitoring methods ....................................................... 110 Rivers .............................................................................................................................................. 110 Biological Quality Elements (BQEs)