Transcript Conceptual Ecological Model of San Acacia Reach of Middle

Conceptual Ecological Model of San Acacia Reach of Middle Rio Grande River – 2/13/07 1st Draft
Ibis Ecosystem Associates, Inc.
Discharge of Contaminants
Into Stream System
Degraded Water Quality
Diversion & Regulation
of Stream Water
River Channel
Fragmentation
Severe Flow
Reductions
Structural Alteration &
Development of Floodplain
Loss of Natural Variability
In Annual & Seasonal
Discharge Pattern
& Hydrograph
Introduction and Spread of
Non-native Vegetation
Floodplain
Loss &
Fragmentation
Floodplain
Lowered
Water Table
Loss of
Connectivity
Between
Floodplain &
Native Desert
Habitat
Loss of Persistent
Moisture Levels &
Wetland Habitats
In Riparian Areas
Saltcedar
Proliferation
High Temperature,
High pH, Low DO
Barrier to
Upstream
Movement of
Silvery
Minnow
Hydrologic Degradation of River Channel Habitat:
•Reduced Magnitude & Duration of Spring Peak Flows
•Reduced Flowing Water With Low-Moderate Currents
•Narrowing of River Channel
•Reduced Over-bank Flooding in Spring
•Dewatering of River Channel & Formation of Isolated Pools
•Reduced Sand and Silt Substrates
•Reduced Eddies From Debris Piles, Pools, & Backwaters
Increased Fire
Frequency &
Intensity In
Riparian Areas
Loss of Dynamic Cycles
Of
Riparian Habitat Succession
River Channel Habitat Quality:
•Perennially Flowing River With Peak
Spring Flows and Over-bank Flooding
•Aggrading River With Shifting
Sand Substrate
•Sinuous, Braided River That
Freely Migrates Across Floodplain,
Producing Eddies From Debris Piles,
Pools, & Backwaters
Rio Grande
Silvery
Minnow
Drivers
Effects
Stressors
Attributes
Floodplain Habitat Quality:
•Persistent Moisture Levels &
Wetland Habitats in Riparian Areas
•Highly Variable Mosaic of
Ephemeral Wetland Habitats,
Supporting Willow & Cottonwood
Stands Adjacent to Wetland Areas
•Unfragmented Landscape of Wide
Lateral Extent, With Riparian Habitat
Connected to Native Desert Habitat
Southwestern
Willow
Flycatcher*
* Impact of cowbird on flycatcher nesting to be covered in text.
Conceptual Ecological Model of San Acacia Reach of Middle Rio Grande River – 10/07 Draft
Diversion & Regulation
of Stream Water
Altered Physical &
Chemical Characteristics
Of River Water:
•Reduced Sediment Load
•Reduced Temperature
•Increased Ammonia
Barrier to
Upstream
Movement of
Silvery
Minnow
Drivers
Stressors
Effects
Attributes
Rio Grande
Silvery
Minnow
River
Channel
Fragmentation
Severe
Flow
Reductions
Loss of Natural Variability
In Annual & Seasonal
Discharge Pattern
& Hydrograph
Hydrologic Degradation of River Channel:
•Reduced Magnitude & Duration of Spring Peak Flows
•Reduced Channel Avulsion During Spring Peak Flows
•Reduced Over-bank Flooding During Spring Peak Flows
•Reduced Flowing Water With Low-Moderate Currents
•Narrowing of River Channel
•Dewatering of River Channel & Formation of Isolated Pools
•Reduced Sand and Silt Substrates
•Reduced Eddies From Debris Piles, Pools, & Backwaters
River Channel Quality:
•Natural Variability In River Flow
Dynamics, With Peak Spring Flows,
Avulsion, & Over-bank Flooding
•Aggrading River With Shifting
Sand Substrate
•Sinuous, Braided River That
Freely Migrates Across Floodplain,
Producing Eddies From Debris Piles,
Pools, & Backwaters
Aquatic Communities:
•Viable Populations of
Key Indicator Groups
of Aquatic Fauna
•Aquatic Fauna
Community Diversity
Structural Alteration &
Development of Floodplain
Introduction & Spread
Non-Native Vegetation
Loss of Persistent
Moisture Levels
& Wetlands
In Riparian Areas
Floodplain Quality:
•Persistent Moisture Levels in
Wetlands & Riparian Areas
•Highly Variable Mosaic of
Ephemeral Floodplain Communities,
Supporting Willow & Cottonwood
Stands Adjacent to Wetland Areas
•Non-fragmented Landscape of Wide
Lateral Extent, With Floodplain
Connected to Native Desert
Marsh Communities:
•Creation of
New Marshes
•Persistence of
Established Marshes
Floodplain
Lowered
Water Table
Floodplain
Loss &
Fragmentation
Increased Fire
Frequency &
Intensity In
Riparian Areas
Loss of
Connectivity
Between
Floodplain &
Native Desert
Loss of Dynamic Cycles Of
Riparian Plant Succession,
Producing Dense Even-aged
Stands, & Resulting In Loss
Of Habitat Mosaic
Cottonwood – Willow
Communities:
•Seedling Recruitment
•Persistence of
Established Communities
Southwestern
Willow
Flycatcher
Conceptual Ecological Model of Working Hypotheses
Aquatic Communities
San Acacia Reach of Middle Rio Grande River
10/07 Draft
Episodic Flow Events
Channel Avulsion
& Scouring
Recruitment-Level Flow Events
•April-June
3,000 – 4,000 cfs
2-Week Duration
3-Year Frequency
Hydrologic Connectivity
•River Channel to Floodplain
•Surface Water to Groundwater
Bank-full Flow
&
Dynamic In-Channel Morphology
Diverse Sediment Size
Distribution &
Shifting Sand Substrate
Persistent Pools
As Aquatic Refugia
During Dry Periods
Over-bank
Flow
Backwater
Nursery Habitat
Prevention of Stranding
With
Water Level Recession
River & Floodplain
Management
Hydrologic &
Geomorphic Effects
Aquatic Habitat Heterogeneity:
•Multi-Threaded Channel
•Dynamic/Avulsive Channel
•Channel Width/Depth Ratio
•Backwaters
•Woody Debris
Aquatic
Community
Attributes
Performance
Measures
Aquatic Fauna
Community Diversity
Viable Populations of Key Indicator
Groups of Aquatic Fauna
(Including Rio Grande Silvery Minnow)
Recruitment To Adult Stage
Survivorship By Age Class
Population Geometric Growth Curves
Conceptual Ecological Model of Working Hypotheses
Marsh Communities
San Acacia Reach of Middle Rio Grande River
10/07 Draft
Episodic Flow Events
•7,000 – 10,000 cfs
•1-week Duration
•10-Year Frequency
Channel Avulsion
& Scouring
Maintenance-Level Flow Events
3-Year Frequency
Bank-full Flow
&
Dynamic In-Channel Morphology
Site Preparation & Management
•Removal of Non-Native Vegetation
•Fire Management
•Other
Hydrologic Connectivity
•River Channel to Floodplain
•Surface Water to Groundwater
Groundwater
Level
Over-bank
Flow
Water Level Fluctuation
•Minimum 3-Foot Fluctuation
•< 3-Year Frequency
Marsh Community Creation:
•Active Channel Marsh Communities
•Marshes Sustained by Surface Water & Groundwater
•Marshes Sustained Entirely By Groundwater
Marsh Community Maintenance:
•Active Channel Marshes
Frequency, Location, & Spatial Coverage
of Newly Created Marshes
River & Floodplain
Management
Marsh Community
Attributes
Hydrologic &
Geomorphic Effects
Performance
Measures
Marsh Community Maintenance:
•Marshes Sustained by Surface Water & Groundwater
•Marshes Sustained Entirely By Groundwater
Longevity and Succession
Of Established Marshes
Spatial Coverage of
Each Marsh Community Type
Conceptual Ecological Model of Working Hypotheses
Cottonwood - Willow Communities
San Acacia Reach of Middle Rio Grande River
10/07 Draft
Episodic Flow Events
Recruitment-Level Flow Events
< 5-Year Frequency
Hydrologic Connectivity
•River Channel to Floodplain
•Surface Water to Groundwater
Over-bank
Flow
Groundwater Level:
Depth To Groundwater
Of 3 – 6 Feet
Channel Avulsion
& Scouring
Creation of Scoured Habitat
For Seedling Recruitment,
Formation of Bars and Islands
For Willow Establishment
Water Level Fluctuation
•Soil Wetting May-June
•Maximum Groundwater
Recession Rate of 2 – 4 cm/day
Site Preparation & Management
•Removal of Non-Native Vegetation
•Fire Management
•Other
River & Floodplain
Management
Hydrologic &
Geomorphic Effects
Successful Recruitment
Of Cottonwood &
Willow Seedlings
Persistence of Established
Cottonwood & Willow
Communities
Cottonwood/Willow
Community
Attributes
Performance
Measures
Frequency, Location, & Spatial Coverage
Of Seedling Recruitment Of
Cottonwood and Willow
Location, Spatial Coverage, & Longevity
Of Established Cottonwood & Willow
Communities