CSR_Module5_Green Earth Initiative, Tree Planting Day
July 29-330-Greg Schmidt
1. USDA is an equal opportunity provider, employer, and lender.
Accounting for Climate in the Application of State and
Transition Models on Landscapes with Mixed Landuse
July 2019 | Greg Schmidt and Nels Barrett
2. Outline
1. Review: What is a state and transition model?
2. How does climate relate to ecological sites and STMs?
3. How can we use STMs in a changing climate?
4. How do multiple land uses affect STMs?
5. How do we assess the conservation value of different land use states?
3. Ecosites and State and Transition Models
Jack Pine Forest Phase
Dry Sand Prairie Phase
Oak/Red Maple Forest State
Jack Pine Barrens Phase
*Reference Community
NaturalSuccession
MoreFire
Red Pine Plantation State
Suppress Fire
Cut/Herbicide red
maple, Burn, Plant
jack pine
Jack Pine Barrens Reference State*
*Reference State -Natural Range of Variability
A Guide to Management Options of the Site
Clear Cut,
Plant red
pine
4. Vegetation Dynamics
Scrub
1 – 5 m
Dry
Woodland
5 – 25 m
Moist
Forest
25-40 m
Desert
Grassland
Short
Grassland
Tall
Grassland
Seasonal HumidArid
Moisture
Disturbance
Woody
Herbaceous
Fuel productionFuel dryness
Fuel availability
Unbroken Flat
Landscapes
Hilly Sheltered
Landscapes
Maximum height limited
by moisture stress
5. 1.1 Emergent
Marsh
1.4 Inundated
Shrub Swamp
1.2 Wet Meadow
1.3 Swamp Forest
Semi-permanentlypondedphases
Stand Replacement Event
Seasonallyponded/Saturatedphases
Drier
Wetter
Disturbance
Succession
• Water table and degree of ponding in
wetland can is sensitive to amount of
precipitation and PET.
• Complex Spatial Zonation based on
wetness encompassed within poorly
drained site concept.
• Annual variability is encompassed by
species life cycles and masks short
term trends.
• Short term (decadal) cyclical trends in
climate translates to shifting spatial
zonation boundaries.
• Longer term unidirectional trends not
accounted for in STM –commensurate
with a change in drainage class and
therefore a change in site concept.
Wetland Ecosite Space Time Continuum
Upland Meadow
Or Wet Meadow
Wet Meadow
Or Emergent Marsh
Emergent Marsh
or Aquatic Bed
Wet Decade
Dry Decade
Drier
Wetter
Disturbance
Succession
6. Hillslope Space Time Continuum
+Moisture
+Mineral Bases
+OM
+Nitrogen
-Moisture
-Mineral Bases
-OM
-Nitrogen
Mesophytic lower slope vegetation:
• Drought intolerant
• Nutrient enriched
Xerophytic upper slope vegetation:
• Drought tolerant
• Nutrient starved
Drier climate will result in a downward shift in
hillslope vegetation zonation
Moister climate will result in an upward shift in
hillslope vegetation zonation.
Hawthorne, S. and Miniat, C.F., 2018. Topography may mitigate drought effects on vegetation
along a hillslope gradient. Ecohydrology, 11(1), p.e1825.
Vose, J.M. and Elliott, K.J., 2016. Oak, fire, and global change in the eastern USA: What might
the future hold?. Fire Ecology, 12(2), pp.160-179.
7. Altitudinal Space Time Continuum
Warmer climate can expect upward shift in altitudinal
vegetation zonation.
Cooler climate can expect downward shift in
altitudinal vegetation zonation.
Subalpine Forest
Montane Forest
Deciduous Advantage
• Warm Growing Season
• Rapid Nutrient Turnover
• High Peak Capacity for Photosynthesis
Evergreen Advantage
• Cool Growing Season
• Slow Nutrient Turnover
• Low Peak Capacity for Photosynthesis
8. Vegetation Climate Zonal Space Time Continuum
– Eastern US
Temperate Mesophytic
Deciduous Forest
Temperate Oak
Woodlands
Temperate Pine
Woodlands
Subtropical
Laurophyllous
Evergreen Forest
(Magnolia-Beech)
Subtropical
Sclerophyllous
Evergreen Woodlands
(Live Oak-Palmetto)
Subtropical Pine
Woodlands
(Longleaf Pine)
Hemiboreal Mixed
Forest
(Beech-Hemlock)
Boreal/Subalpine Forest
(Spruce-Fir)
Warm Season
Tall Grassland/Prairie
(Big Bluestem)
Cool Season
Short Grassland/Steppe
Tropical Moist ForestTropical Dry ForestTropical Savanna
STM Site B
STM Site A
9. Trends in thermal and moisture regimes
(Southern Great Lakes Region)
https://phytoclast.github.io/ClimateClassification/
2070
1990
Holocene Optimum
Glacial Maximum
2070
1990
Holocene Optimum
Glacial Maximum
Lat: 41.63°; Lon: -83.82°; Elev: 245 m
MAAT: 9.1°C; MAP: 918 mm
Warm Month: 21.9°C; High: 28°C; Cold Month: -4.9°C; Low: -9.3°C
Growing Season Temperature: 17.4°C; Annual Extreme Low: -23.8°C
P/PET: 1.55; Surplus: 382 mm; Deficit: 57 mm; Peak AET: 95 mm
Warm-Mild (Lower-Montane) Meso-Temperate, Moist-Humid Isopluvial
20th and 80th percentile
monthly precipitation
plant
physiognomic
thresholds
Normal climate variation =
No change in normal range of
possible vegetation
Long term persistent change in climate =
Complete turnover in species available.
11. Fluid State and Transition Model
Generic Forest Phase
Generic Prairie Phase
Generic Seminatural State
Generic Barrens Phase
NaturalSuccession
MoreFire
Generic Cultural State
Everything by accident
Restore
Generic Natural Upland Low Nutrient
Reference State*
*Reference State -Natural Range of Variability
• A Generic Guide to Management Options of the Site decoupled from a fixed
climate. Change is gradual, outcome is uncertain – what is the threshold
for a new alternative climate state? Or is it a shifting reference?
• Relies heavily on functional vegetation ecology and knowing the autecology
of individual species.
• Priority given to locally native plant communities with higher mean species’
“conservancy” value indicating a reference condition, but change from
historic composition is inevitable.
By Design
?
?
?
? ?
By Neglect
12. Multiple Use Landscape
Rangeland
Forestland
Cultural
What is the object of Conservation Focus?
Sustainability of Human Life on Earth
What do we need for this?
• Cultural Services:
• Food
• Shelter
• Ecosystem Services:
• Clean Air
• Clean Water
• Building Materials
• Biological Values:
• All the critters
required to keep
giving you these…
• Which means that
not all NPP can go
towards these…
Natural
Vegetation
Cultural
Vegetation
• But a fragmented landscape offers an incomplete package
13. Aggregating Alternative States by magnitude of
Ecological Integrity*
Natural Vegetation — vegetation where ecological
processes primarily determine species and site
characteristics; that is, vegetation comprised of a largely
spontaneously growing set of plant species that are
shaped by both site and biotic processes.
Semi-Natural Vegetation — vegetation in which past or
present human activities significantly influence
composition or structure, but do not eliminate or
dominate spontaneous ecological processes activity. Semi-
natural sites typically have no recent historical analogue,
but may be composed of native or introduced species.
Cultural Vegetation — vegetation with a distinctive
structure, composition, and development determined by
regular human activity. Often managed to obtain specific
products to the exclusion of rest of the ecosystem. Includes
cropland and urbanland.
*Concepts expanded from United States National Vegetation Classification http://usnvc.org
• Biological Values
• Ecosystem Services
• Cultural Services
• Biological Values
• Ecosystem Services
• Cultural Services
• Biological Values
• Ecosystem Services
• Cultural Services
Conservation Practices?
Conservation Practices?
Conservation Practices?
Ranking of Reference Status
A – pristine reference
B – imperfect, de facto reference
C – needs restoration
D – barely recognizable, lost cause
Fail Seminatural
Conservation ValueDefinitions
?
?
?
14. Wetlands
Reference
Ruderal Woody
Ruderal
Herbaceous
Semi-Natural Vegetation
Cultural Vegetation: Urban or Agricultural
Unsustainable
Cultural Phases
Sustainable
Cultural Phases
Conservation
Feature
• Cover Crop (340)
• Conservation Crop Rotation
(328)
• Nutrient Management (590)
• Integrated Pest Management
(IPM) (595)
• Conservation Cover
(327)
• Grassed Waterway (412)
Forest or Shrubland
Grassland
• Prescribed Burning (338)
• Early Successional Habitat
Development/Management
(647)
• Brush Management (314)
• Forest Stand Improvement
(666)
• Tree/Shrub Site Preparation
(490)
• Tree/Shrub Establishment (612)
• Wetland Enhancement (659)
• Wetland Restoration (657)
• Wetland Wildlife Habitat
Management (644)
• Brush Management (314)
• Herbaceous Weed Control (315)
• Upland Wildlife Habitat
Management (645)
• Restoration and
Management of Rare
and Declining Habitats
(643)
• Brush Management
(314)
• Herbaceous Weed
Control (315)
Conservation Practices
15. Conservation Scale
Small area of distinctive composition,
nested within a larger community. Microsites
Small area, disconnected from site or
without adjacent community
Ecosystem Elements
Limited maintenance of a static
species composition across microsites
Community
Management of multiple successional
phases irrespective of adjacent sites.
Site Ecosystem
Management of multiple adjacent
sites, needed for wide ranging wildlife
species.
Landscape Ecosystem
SpecieslistsSTM
Agency Product Planning Level
Shift in frame of
reference due to
high intensity
environmental
changes?
Manage viability of entire species;
Quarantine of invasive species and
diseases
Biotic Province
Manage viability of area species pool
irrespective of landscape
Ecoregion/Ecological
Inference Area
Management of multiple biomes,
adapting to climate readjustments;
Quarantine of invasive species and
diseases
Biotic Realm
Carbon and CFC emissions; fisheries;
human populations; etc.
Global
MLRA
GRIN
Database
16. Biogeographic Hierarchy
Biotic Province:
Eastern North
American Forest &
Woodland Division
(USNVC)
Ecological
Inference Area:
MLRA
Nearctic Realm
• Biotic Realm: area of species sharing a deep history of coevolution (native in the broadest sense)
• Biotic Province: area of species sharing a more recent history of interaction through climate
cycles, lacking barriers to migration.
• Ecological Inference Area: smaller area of homogenous flora and fauna where
composition is dependent only on local differences in substrate and climate.
17. Outline
1. What is a state and transition model?
• Integrates ecosystem response to multiple inputs expressed as change in vegetation or land cover.
2. How do we capture climate variability in the context of a site description?
• Currently, within the existing framework, climate variability is accounted for as internal dynamics.
• These internal temporal dynamics translate into spatial dynamics within the site.
• Internal dynamics can be scaled up beyond the single site to the landscape and beyond.
3. Can we develop credible templates that reflect complex dynamics?
• Dynamics show patterns that are often repeated at different scales, and arrayed along various
gradients (landform vs. altitude vs. latitude) that exhibit different expressions of vegetation at each
level.
• Despite complexity, there is still a restricted range of vegetation structure and function that can be
represented by a generic STM with an underlying shifting community composition.
4. How do multiple land uses affect the development of a STM?
• Uncertainty and variability among fragments in multi-use landscape makes it difficult to represent
every combination of cover type, and may require aggregating alternative states according to the
intensity of land use.
5. How can we assess the value of different states?
• Within the reference state, we grade sites according to how well they function like the reference.
• Among higher intensity land uses or greater intensity of change, we can adjust a larger ecological
inference area to determine our new reference and to ensure we ensure the viability of native species
where they can thrive.
18. Disclaimer
The findings and conclusions in this presentation are those of the author(s)
and should not be construed to represent any official USDA or U.S.
Government determination or policy.
Notes de l'éditeur
Climate and land use are two different things that complicate conservation planning. My goal is to provide a framework to think about these two problems.
Climate and land use are two different things that complicate conservation planning. My goal is to provide a framework to think about these two problems.
A state and transition model is an outline of the vegetation dynamics in context of the natural range of variability in climate and disturbance history, and potential land uses.
Spatial vegetation patterns are set by climate, but only with interaction with other factors like disturbance regime. Disturbance is often fire, wind, flood, and animal driven. Fire frequency = ignitions × fuels × connectivity.
Year to year variability in precipitation of will not change vegetation patterns as it encompasses the lifecycles of most perennial species. Individual species may be affected by short term wet or dry episodes that have an immediate effect on seedling establishment or adult plant mortality, but this maintains status quo. But variation by decade or longer is enough to change the relative position of vegetation zonation based on cumulative effect of wetter versus drier years on recruitment/mortality dynamics. Longer period variability is needed to systematically affect woody vegetation since it takes longer to reach structural maturity. [Generally, annual precipitation in Michigan expected to be ±20-25% for one out of ten years, and variation in decadal means are about ±10-15% one out of ten decades.]
Drier climate can expect downward shift in hillslope vegetation zonation:
Moisture affected directly by virtue of lower cumulative flow of moisture downslope.
Shift in nutrient gradient is more indirect:
Losses of nitrogen to atmosphere due to fire.
Losses of nitrogen via shift to species composition with lower quality leaf litter.
However weathering of bases will be less severe.
Wetter climate can expect upward shift in hillslope vegetation zonation.
Cooler climate can expect downward shift in altitudinal vegetation zonation.
Warmer climate can expect upward shift in altitudinal vegetation zonation: isolated peaks may completely lose alpine and subalpine zones.
An array of possible vegetation formations that are affected by temperature and moisture regimes. Fire regime and site nutrient/moisture constraints must also be considered. Adjacent sites may overlap in the vegetation represented in their STM.
If precipitation variability should be considered in context of monthly potential evapotranspiration. Impacts of precipitation variability should be more significant for months with a potential for cumulative soil moisture deficit. Historic changes in thermal and moisture regimes have been dramatic, but should be put into a plant physiology and soil moisture context.
Compatibility of novel species composition assessed by considering natural geographic barriers and historic species migration. Species that we have since the last ice age are already filtered of species unable to find a suitable niches somewhere on the continent in context of the wide magnitude of change, though luck is also at play.
A climatically decoupled state and transition model allows for planning around alternative reference states if final vegetation trajectory is uncertain.
Natural habitat provides services not available in by cultural vegetation, but effectiveness declines with fragmentation.
Each land use decision potentially moves a site further from a reference optimum. Fragmentation, climatic adjustments, fickle markets, and continued invasive species introductions conspire to prevent this continuum of these novel states from reaching a new equilibrium. Prior to more detailed inventory, a set of generic alternative states can be defined in terms of their over all human footprint. Partially compromised reference conditions can be recognized as a grade, if species composition still recognizable to a natural community type. Conservation practices are intended to partially compensate or minimize loss in ecological integrity.
The types of conservation practices employed vary according to intensity of land uses.
Conservation planning must consider a landscape scale commensurate with the magnitude of environmental change. The object of conservation may shift away from “authentically original vegetation” on a particular site to that of the more desperate goal of viability of the whole biota somewhere in a novel landscape as it relates to a shifting “autecological window”.
A biogeographic hierarchy should be considered based on this history, to determine appropriate scale of plant conservation.