Applied Ecosystem Services, LLC

The Environmental Issues Doctor

Photo of Fit Model to Data


Estimated reading time: 2 minutes

To make informed regulatory decisions it is necessary to understand differences between ecological and environmental data. Analyses of environmental data historically use models adapted from engineering models by numerical ecologists for ecological data collected by academic and research agency scientists. These numeric and statistic models require well-structured data collected to fit assumptions and requirements of the models. This works for researchers who identify a question to be answered and work forward from that to determine when, where, and how much data need collecting to answer that question. The research approach of fitting data to models has leaked into the analyses of environmental data gathered in response to statutory and regulatory requirements. Most often, the results are mis-leading or incorrect. Regulatory decisions based on these results are ineffective at best or economically and socially harmful at worst.

Environmental data are messy and unstructured, collected to support environmental permit applications and monitor compliance with permit conditions. Locations change over time, data collection frequency is irregular, and chemical or biological data elements can cease being collected and re-instated at a future time. Such data cannot be fit to research models such as species diversity, indices of biotic integrity (IBI) or community indices (CI), predictive models based on expected taxa (RIVPACS), hydroelectric fish passage models (CRiSP), or pit lake water quality (PITLAKQ). For real-world environmental regulatory decision-making it is necessary to fit the model to the data by applying the appropriate statistical models.

This work was originally published on the Applied Ecosystem Services, LLC web site at

It is offered under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International license. In short, you may copy and redistribute the material in any medium or format as long as you credit Dr. Richard Shepard as the author. You may not use the material for commercial purposes, and you may not distribute modified versions.

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    Factors Limiting Species Populations: 1


    Estimated reading time: 1 minutes

    There are many plant and animal species considered to be threatened, endangered, or of special concern to regulators and the public. Correctly estimating population sizes, relationship to habitats, and potential effects of anthropomorphic activities is crucial to making informed policy and regulatory decisions. Environmental conditions affecting species populations are the limiting factors. Quantifying limiting factors is fundamental to developing policies and practices that are most likely to create the desired future conditions for the species and its habitats.
  2. Photo of Forecasting Water Quality

    Forecasting Water Quality


    Estimated reading time: 1 minutes

    Predicting concentrations of chemicals in surface waters is a major component of permitting decisions, from NEPA impact assessments and NPDES point source discharge to mine closure and Superfund liability bond releases. Decision delays are costly for operators, and regulators are too often sued by those claiming that decisions were based on inadequate data. Usual approaches to forecasting chemical concentrations are to build complex numeric ecosystem models or predict concentrations of single chemicals rather than the entire set of chemicals of interest.

Contact me when your data analyses must be technically sound and legally defensible.