Michigan Tech Research Institute (MTRI)

Linking Remote Sensing and Process-Based Models to Assess Land Use and Climate Change Impacts on Plant Invasion in Great Lakes Coastal Wetlands

Invasive plants in coastal wetlands of the Great Lakes are degrading wetland habitat, decreasing biodiversity, and reducing ecosystem services. Our objective is to refine and integrate process-based hydrological and ecological models with remote sensing products to investigate how changes in upland land use and climate alter risk of plant invasions and ecosystem services in coastal wetlands.

A person standing in phragmites and another in typha.

Linking Ecological and Hydrological Models

Changes in upland land use and climate were simulated in order to understand the impacts of changing water and nutrient loads on coastal ecosystems.

ILHM and Mondrian flowcharts.
Diagram of water and nutrient loads.

MONDRIAN: Modes of Nonlinear Dynamics in Resource Interactions and Nutrient Cycling

Map of carbon and nitrogen cycle in plants.

Individual-based ecosystem model spanning five levels of organization:

  • Individual ramet growth
  • Translocation of C and N within clones
  • Population processes (fecundity, mortality)
  • Community modeling (competition for light, N)
  • Ecosystem processes (water level, biogeochemistry, closed C and N budgets)

LHM: Landscape Hydrology Model

Water table diagram.
Landscape hydrology model.
  • Simulates full water and energy balance
  • Integrated Surface Water and Groundwater
  • Interactions between soil water and vegetation
  • Fully distributed
  • Process based
  • Four main zones

Field and Experimental Research

Field work was conducted to understand both the hydrology and plant invasions. Remote sensing data were used for landscape scale validation of results and to parameterize models.

Monitoring Invasion of Problematic Wetland Plant Species

Collage of a lower Michigan satellite image and three photos of phragmites and typha.
Typha x glauca invading sedge-rush marsh in northern Michigan coastal wetlands 

Controlled Experiment With 100 Mesocosms at Two Latitudes

Collage of controlled experiment photos and charts.

Mapping Distribution of Wetland Invaders and Land Use

Mapping Distribution flowchart.
Example remote sensing map of vegetation.

Modeled Results

Nutrient loads noted by color on map of lower Michigan.
Charts of N inflow.

Land Use and Land Cover Analysis

Land cover map of lower Michigan.

LCLU Analysis charts.

Invader NPP Proportion graphs.
Muck acretion graph.

Results

Integration of remote sensing, field data and modeled results show greater nitrogen loading and invasion of problematic wetland plants in southern half of Michigan's Lower Peninsula due to land use.

  1. LHM model shows greater N loading in southern half of region due to land use
  2. Coastal mapping shows greater plant invasions in southern half of region
  3. Coastal wetland model shows how large plant size gives invaders ecological advantage when N inflows are high
  4. Controlled mesocosms experiment fails to confirm invasion mechanism (2 years may not be enough)
  5. Linked models suggest intermediate C accretion (100 gC m-2 y-1) based on hydroperiod and ecosystem processes
  6. Stay tuned for the “Grand synthesis:” formal model linking and validation via remote sensing and field data

Next Steps

Lower Michigan outlined in red with select points noted.

  • Run LMH Model for all watersheds
  • Compare land use by watershed to model output
  • Simulate Degree of Invasion using N delivery and Hydroperiod in community-ecosystem model
  • Compare Simulated Degree of Invasion for each location
  • Validate native and invader biomass, litter, and muck C storage for each site
  • Apply validated, linked models around Michigan coast to assess invasion risk in present and future scenarios