Use of Adapted USEPA Ecological Condition Reporting Framework

for Monitoring Watershed Health in California

Introduction

The California Watershed Management Strategic Action Plan calls for state watershed programs to “evaluate the utility of existing watershed related indicators for assessing watershed conditions and trends, and the use of performance measures for assessing watershed program progress”. The Action Plan was developed by a Steering Committee that is co-chaired by Resources Agency and CalEPA, has representatives from 16 of their boards, departments, conservancies and commissions, and also has representatives from the Departments of Food and Agriculture and Health Services. On February 2, 2006, the Steering Committee adopted a modified version of a USEPA framework,developed for reporting on ecological conditions, for use in the assessment of California’s watershed health and to guide the selection of watershed indicators for future monitoring efforts.

Objectives

Recognizing a gap in the information required to assess the integrity of ecological systems in a systematic way across regions, the U.S. Environmental Protection Agency’s Science Advisory Board developed a sample framework as a guide for designing a system to assess, and then report on, ecological condition at a local, regional, or national scale. The objectives of this framework are to:

  • Assure that important ecological attributes are accounted for in assessing ecological conditions
  • Assure that information is measured systematically by the Agency’s programs;
  • Provide a template for assembling information across Agency programs and from other agencies; and,
  • Provide an organizing tool for synthesizing large numbers of indicators into a scientifically defensible, yet understandable, report on ecological condition.

The framework

The framework relates the goals and objectives of programs and management efforts to ecological conditions. Information from specific measurements is aggregated into indicators which describe the condition of ecosystem characteristics or ‘Essential Ecological Attributes”. These attributes are interdependent and, taken together, describe the condition of an ecosystem. Program goals and objectives can be evaluated in light of the ecological conditions described by the attributes. This framework provides a scientifically defensible approach for aggregating and assessing a multitude of environmental data. The framework provides for evaluation of a variety of environmental management goals. This framework for consolidating information can be used as part of a reporting system (see figure below) that consists of:


Goals and objectives which articulate the desired ecosystem conditions that will result from program(s) and management efforts;

Essential ecological attributes, the major ecological features of an ecosystem or landscape (further discussed in the next section);

Ecological indicators, or measurable characteristics related to the structure, composition, or functioning of ecological

ems; and,

Measures, or the specific monitoring variables measured in the field and aggregated into one or more ecological indicators.

Essential Ecological Attributes for Reporting Ecological Conditions

EPA’s Science Advisory Board framework identifies six essential ecological attributes (EEAs) that summarize the major ecological features in any system. The EEAs divide up the universe of information that describes the state of an ecological system in a logical manner that is solidly grounded in current scientific understanding.

The EEAs include three ecological attributes that are primarily “patterns”:

  • Landscape condition
  • Biotic condition
  • Chemical/physical characteristics

The other three attributes are primarily “processes”:

  • Hydrology/geomorphology
  • Ecological processes
  • Natural disturbance

For a list of EEAs and the reporting categories included in each attribute, see Appendix.

The Adapted Framework for Reporting on Watershed Health in California

The California Watershed Action Plan Steering Committee adapted this framework for the purposes of assessing watershed health by adding an attribute category related to socio-economic condition. This modification acknowledges that humans and their activities are integral parts of watersheds.

Essential Watershed Attributes

Landscape condition. The extent, composition, and pattern or structure of the landscape (an area composed of a mosaic of interacting ecosystems or habitat patches).

Biotic condition. The structure and composition of the biota below the landscape level (i.e., for ecosystems or communities, species/populations, individual organisms, and genes).

Chemical and physical characteristics, which include measures of physical parameters and concentrations of chemical substances that are naturally present in the environment.

Ecological processes, defined as the metabolic functions of ecosystems at the ecosystem or landscape level, and include energy flow, elemental cycling, and the production, consumption and decomposition of organic matter.

Hydrology/Geomorphology, characteristics that reflect the dynamic interplay of water flow and landforms

Natural disturbance regimes, which are discrete and recurrent disturbances that may be physical, chemical, or biological in nature.

Socio-economic condition. A working definition of this seventh attribute and a list of possible indicators have not yet been developed.

Example of Potential Indicators

Examples of potential indicators for attributes are included in the following summary of Table E2 from the Science Advisory Board Executive Summary. These will be considered for applicability to the California Watershed Action Plan.

Ecological Attributes and Categories / Examples of Indicators
Landscape Condition:
Extent of ecological system/habitat type;
Composition;
Pattern and Structure / area; perimeter-to-area ratio; core area; elongation;
number of habitat types; number of patches of each habitat; size of large patch; presence/absence of native plant communities; measures of topographic relief, slope, and aspect;
dominance; contagion; fractal dimension; distance between patches; longitudinal and lateral connectivity; juxtaposition of patch types or serial stages; width of habitat adjacent to wetlands
Biotic Condition:
Ecosystems and Communities;
Species and Populations;
Organism Condition / Community Extent e.g. extent of native ecological communities; extent of successional states
Community Composition e.g., species inventory; total species diversity; native species diversity; relative abundance of species; % non-native species; presence/abundance of focal or special interest species (e.g., commonness/rarity); species/taxa richness; number of species in a taxonomic group (e.g., fishes); evenness/dominance across species or taxa
Trophic Structure- eg food web complexity; presence/absence of top predators or dominant herbivores; functional feeding groups or guilds
Community Dynamics e.g., predation rate; succession; pollination rate; herbivory; seed dispersal
Physical Structure e.g., vertical stand structure (stratification or layering in forest communities); tree canopy height; presence of snags in forest systems; life form composition of plant communities; successional state
Population Size e.g., number of individuals in the population; size of breeding population; population distribution; number of individuals per habitat area (density)
Genetic Diversity e.g., degree of heterozygosity within a population; presence of specific genetic stocks within or among populations
Population Structure e.g., population age structure
Population Dynamics e.g., birth and death rates; reproductive or recruitment rates; dispersal and other movements
Habitat Suitability (Focal Species) measures of habitat attributes important to focal species
Physiological Status e.g., glycogen stores and blood chemistry for animals; carbohydrate stores, nutrients, and polyamines for plants; hormone levels; enzyme levels
Symptoms of Disease or Trauma e.g., gross morphology (size, weight, limb structure); behavior and responsiveness; sores, lesions and tumors; defoliation
Signs of Disease e.g., presence of parasites or pathogens (e.g., nematodes in fish); tissue burdens of xenobiotic chemicals
Chemical and Physical Characteristics (water, soil, sediment)
Nutrient Concentrations;
Trace Inorganic and Organic Chemicals;
Other Chemical Parameters;
Physical Parameters / Nitrogen e.g., concentrations of total N; NH4, NO3; organic N, NOx; C/N ratio for forest floor
Phosphorus e.g., concentrations of total P; ortho-P; particulate P; organic P
Other Nutrients e.g., concentrations of calcium, potassium, and silicon
Metals e.g., copper and zinc in sediments and suspended particulates
Other Trace Elements e.g., concentrations of selenium in waters, soils, and sediments
Organic Compounds e.g., methylmercury, selenomethionine
pH e.g., pH in surface waters and soil
Dissolved Oxygen/ Redox Potential e.g., dissolved oxygen in streams; soil redox potential
Salinity e.g., conductivity
Organic Matter e.g., soil organic matter; pore water organic matter concentrations
Other e.g., buffering capacity; cation exchange capacity
Soil/Sediment e.g., temperature; texture; porosity; soil bulk density; profile morphology; mineralogy; water retention
Air/Water e.g., temperature; wind velocity; relative humidity; UV-B PAR; concentrations of particulates; turbidity
Ecological Processes;
Energy Flow;
Material Flows / Primary Production: capacity (total chlorophyll per unit area); net primary production (plant production per unit area per year); tree growth or crop production (terrestrial systems); trophic status (lakes); 14-CO2 fixation rate (aquatic systems);
Net ecosystem production: organic carbon storage (forests); diel changes in O2 and CO2 fluxes (aquatic systems); CO2 flux from all ecosystems; comparison of primary production with net ecosystem production; transfer of carbon through the food web;
Growth efficiency: input/output budgets (source identification-stable C isotopes); internal cycling measures (food web structure; rate and efficiency of microbial decomposition; carbon storage); organic matter quality and character;
N and P cycling: input/output budgets (source identification, landscape runoff or yield); internal recycling (N2-fixation capacity; soil/sediment nutrient assimilation capacity; identification of growth-limiting factors; identification of dominant pathways)
Other Nutrient Cycling (e.g., K, S, Si, Fe): input/output budgets (source identification, landscape yield); internal recycling (identification of growth-limiting factors; storage capacity; identification of key microbial terminal electron acceptors)
Hydrology and Geomorphology:
Surface and Groundwater Flows
Dynamic Structural Characteristics
Sediment and Material Transport / Pattern of Surface Flows e.g., flow magnitude and variability, including frequency, duration, timing, and rate of change;
Hydrodynamics e.g., water movement; vertical and horizontal mixing; stratification; hydraulic residence time; replacement time
Pattern of Groundwater Flows e.g., groundwater accretion to surface waters; within-groundwater flow rates and direction; net recharge or withdrawals;
depth to groundwater
Spatial and Temporal Salinity Patterns (estuaries and wetlands) e.g., horizontal (surface) salinity gradients; depth of pycnocline; salt wedge
Water Storage e.g., water level fluctuations for lakes and wetlands; aquifer capacity
Channel Morphology; Shoreline Characteristics; Channel Complexity e.g., mean width of meander corridor or alternative measure of the length of river allowed to migrate; stream braidedness; presence of off-channel pools (rivers); linear distance of marsh channels per unit marsh area; lithology; length of natural shoreline
Distribution and Extent of Connected Floodplain (rivers) e.g., distribution of plants that are tolerant to flooding; presence of floodplain spawning fish; area flooded by 2-year and 10-year floods
Aquatic Physical Habitat Complexity e.g., pool-to-riffle ratio (rivers); aquatic shaded riparian habitat (rivers and lakes); presence of large woody debris (rivers and lakes)
Sediment Supply and Movement e.g., sediment deposition, sediment residence time and flushing
Particle Size Distribution Patterns e.g., distribution patterns of different grain/particle sizes in aquatic or coastal environments
Other Material Flux e.g., transport of large woody debris in rivers
Natural Disturbance Regimes
Forest Fire
Flood
Insect infestation / Frequency e.g., recurrence interval for fires, extreme flood events, insect outbreaks
Intensity e.g., occurrence of low intensity (forest litter fire) to high intensity (crown fire) fires; number of standard deviations from 30-year flood occurrence mean; density (number per area) of insect pests in an area
Extent e.g., spatial extent of fire in hectares; number of stream orders (and largest order) affected by floods; spatial extent of infested area
Duration e.g., length of fire events (from hours to weeks); number of flood affected days, percent of water year (October 1- September 30); length of insect infestation outbreak

The Role of Stressor Indicators

The proposed framework may be used in a scheme that also includes the “parallel universe” of anthropogenic stressors. The SAB report acknowledges the importance of distinguishing between ecological condition indicators and indicators of anthropogenic stressors for the following reasons:

  • Clearly differentiating natural variations from human-induced variations facilitates environmental remediation and natural resource management in those situations where managers do not intend to alter natural variations.
  • Addressing anthropogenic stressors separately enables more systematic assessment of the relationships between these and ecosystem impacts.
  • It encourages indicator selection criteria to be based upon fundamental environmental attributes and processes, rather than current data availability. (Available data generally focus on anthropogenic stressors targeted by environmental programs.)
  • Helps allocates management responsibilities and facilities cross-agency and cross-media coordination of environmental management functions.

Diagram of how stressors relate to ecological attributes in EPA’s SAB framework.

Rationale for Adopting Framework

Rationale for Using an Adaptation of the Science Advisory Board Framework

The SAB framework has many strengths of the approach, including:

  • It represents the product of extensive deliberations by the USEPASAB, and as such, has sound scientific basis.
  • It can be used at various geographic scales: locally, regionally, statewide, and nationwide.
  • It promotes consistent presentation and treatment of ecological information.
  • It provides a checklist of essential ecological attributes that can be used as a guide for designing a system to assess and report on ecological condition.
  • As a checklist, it is organized as a hierarchy that allows the user to judge tradeoffs when all attributes cannot be studied; the hierarchy also provides a roadmap for synthesizing a large number of indicators into a few, scientifically defensible categories, each of which sums up an important ecological characteristic.
  • The results of the “road-testing” of the framework on selected environmental programs indicate that it is comprehensive, applicable to a variety of aquatic and terrestrial ecosystem types, and can be used as a template for synthesizing information from different programs.
  • It provides mechanisms for evaluating stressors, and facilitates program evaluation, and coordination of environmental management functions.

The full SAB report can be accessed at:

An Executive Summary can be accessed at:

1

APPENDIX

1