Nutrient indicator models for determining biologically relevant levels : a case study based on the Corn Belt and Northern Great Plain Nutrient Ecoregion / Charles Clarence Morris, Thomas Paul Simon
1 Introduction -- 2 Methods -- 2.1 Study Area -- 2.2 Field Collection -- 3 Data Analysis -- 3.1 Data Censoring -- 3.2 Drainage Classification -- 3.3 Jenks Analysis -- 3.4 Drainage Category Prevalence Determination -- 3.5 Species Optima Calculations -- 3.6 Nutrient Biotic Index Calculation -- 3.7 Statistical Analysis -- 4 Results -- 4.1 Bin Summary Statistics -- 4.2 Species Optima and Tolerance Classification -- 4.3 NBI Calculation -- 4.4 Test Response Intervals and Shift Response Intervals -- 5 Discussion -- 5.1 Reference Condition and Study Design -- 5.2 Sample Size Needed to Capture Regional Variation -- 5.3 Validation of Calibration Procedure -- 5.4 Nitrogen Relationships with Fish Assemblages -- 5.5 Phosphorus Relationships with Fish Assemblages -- 5.6 Chlorophyll a Relationships with Fish Assemblages -- 5.7 Numerical Nutrient Criteria Derivation -- 5.8 Multidirectional Interpretation -- 5.9 Management Implications: Ramification to Gulf of Mexico Hypoxia Loadings -- 6 Conclusion -- References -- Appendix -- Index
Summary
Nutrient Indicator Models for Determining Biologically Relevant Levels: A case study based on the Corn Belt and Northern Great Plain Nutrient Ecoregion is the first book to provide answers to the management of nutrients based on changes in biological communities. The text describes a case study that is the result of a large scale project in the Corn Belt and Great Plains Nutrient Ecoregion. This study is the first to identify relationships between fish assemblages and nutrient concentrations by Nitrogen species. Species optima based on sensitvity and tolerance to nutrients is modeled.¡ Nutrient Biotic indices calibrated for application are based on the results of years of biological indicator development. Test response intervals and Shift response intervals are formulated and validated against relevant biological assemblage shifts. This case study is the first to suggest recommended values for the nitrogen and phosphorus cycle with identifiable shifts caused in biological assemblages. This will provide watershed and environmental managers with the information needed to manage the inputs into the world's dead zones
