Developing, understanding and using nutrient boundaries ECOSTAT Nutrient workshop 6-7 November 2018, Bucharest, Romania Developing, understanding and using nutrient boundaries presenting the Nutrient Toolkit

Emotions during day 1 of workshop

Session 3a Choice of method, steps in the CIS Guide Section 3 Overview of process (‘road map’) Provides guidance on selecting methods, however all methods should be tested and results compared, wherever possible. Section 4.2 Overview of stepwise procedure

Overview of process (‘road map’) page 35 CIS Section 3 CIS

Overview of process Choice of approaches using flowcharts to illustrate the decisions needed when selecting methods for specific data sets not intended as a prescriptive flow diagram 3.1. Choice of approaches A (continuous data) deals with methods where biological data in the form of an EQR, or a continuous metric, are available 3.2. Choice of approaches B (weak linear relationship, r2 < 0.36) deals with situations where the relationship between nutrient and biology is weak (e.g. multiple pressures occur; other environmental gradients) 3.3. Choice of approaches C (categorical methods) contains categorical methods. These methods place more reliance on an appropriate class width and do not allow for situations where nutrient concentrations do not span the entire status class. Require significant differences of nutrient concentrations between the classes Section 3 CIS

Choice of approaches A continuous Page 38 CIS

Choice of approaches B weak r2 Page 40 CIS

Choice of approaches C categorical Page 42 CIS

Overview of stepwise procedure Step 1: assemble a data set Use summary data not spot samples Ensure nutrient and biological data are spatially and temporally matched Step 2: inspect the data scatterplots; boxplots; outliers; linear response range; trends & patterns Step 3: fit linear regression models Step 4: calculate categorical methods Step 4a: compare results Compare predicted boundary concentrations between methods tested Step 5: compare boundary values Compare predicted boundary concentrations with existing nutrient boundaries (see also CIS result tables for common types sections 4.4 & 4.5) Step 6: validate boundary values Session 4 independent data to demonstrate that predicted concentrations meet ecological Expectations and are likely to protect key taxa associated with good status conditions Pointing to resources in the toolkit that allow you to test each step e.g. page 45 CIS Section 4.2 CIS

We hope you can enjoy the nutrient toolkit!! Use these pages as support while exploring your data and getting familiar with the resources made available. We hope you can enjoy the nutrient toolkit!!