Grassland Management Activity Data: Current Sources and Future Needs

1
Grassland Management Activity Data Current
Sources and Future Needs

• Richard T. Conant
• Keith Paustian

Natural Resource Ecology Laboratory Colorado
State University
2
Distribution/importance of grasslands globally

• 27 of terrestrial surface
• 23 of milk production
• 27 of beef production
• 12 of worlds SOM

3
Potential regional to global C sequestration in
grasslands
460
69.8
71.5
45.5
8.0
2.5
4
C sequestration in grasslands potentials
Improved management with high inputs
Improved management
Native/ Nominal management
Soil carbon
Degraded grassland (1O overgrazing)
Time
5
C sequestration in grasslands moving beyond
potentials

• Most C sequestration estimates are potentials
• Potentials are a good first-cut (sometimes only
  potentials are possible)
• Potentials can inform policy decisions
• What are actual C sequestration rates?
• How much of the potential is likely to be
  reached? How fast?
• To answer these questions, we need current,
  frequent, high resolution, management-relevant
  activity data
• The purpose of this talk is to
• review specific needs for activity data
• review existing activity data
• investigate methods with which we can apply those
  data
• identify new potential sources

6
Methods for estimating C sequestration and
potential
Tier 1 Net soil C changes for mineral soils are
estimated on the basis of relative stock change
factors, applied over a 20 year inventory period
IPCC Default C sequestration factors Factor Level
Climate GPG Default
regime f
Landuse Native Temperate 1.0
Landuse Native Tropical 1.0
Landuse Degraded Temperate 0.93
Landuse Degraded Tropical 0.96
Landuse Improved Temperate 1.17
Landuse Improved Tropical 1.19
Input Medium Temperate 1.0
Input Medium Tropical 1.0
Input High Temperate 1.08
Input High Tropical 1.13
Activity Data Factor Level Climate Area
regime (Kha) f
Landuse Native Temperate 325
Landuse Native Tropical 16
Landuse Degraded Temperate 247
Landuse Degraded Tropical 12
Landuse Improved Temperate 444
Landuse Improved Tropical 24
Input Medium Temperate 241
Input Medium Tropical 2
Input High Temperate 203
Input High Tropical 18
7
Methods for estimating C sequestration and
potential
Tier 2 Stock change factor values can be
estimated from long-term experiments or other
field measurements.
Country-specific C sequestration
factors Activity Level Climate Area
regime (Kha) f
Fert. Low Temperate 325 Fert. Medium
Temperate 318 Fert. High Temperate
247 Graze Heavy Temperate 112
Graze Moderate Temperate 444
Graze Light Temperate 424
Ungrazed Temperate 241
Legumes Yes Temperate 182
Legumes No Temperate 203
Activity Data Activity Level Climate Area
regime (Kha) f
Fert. Low Temperate 325 Fert. Medium
Temperate 318 Fert. High Temperate
247 Graze Heavy Temperate 112
Graze Moderate Temperate 444
Graze Light Temperate 424
Ungrazed Temperate 241
Legumes Yes Temperate 182
Legumes No Temperate 203
8
Methods for estimating C sequestration and
potential
Tier 3 Use a combination of dynamic models
along with detailed soil C emission/stock change
inventory methods.
Ecosystem C model (e.g., Century)

• Driving variables
• Temperature
• Precipitation
• Soil properties
• Vegetation
• Land use/management history
• Current management activities

CO2
Active C
CO2
CO2
CO2
Slow C
Passive C
CO2
CO2
C sequestration rate direct model output or
areal expansion of cellular output
9
Activity data needs

• General data requirements
• Spatial data preferred
• -Soil properties influence C stabilization
• -Climatic regions
• Some measure of uncertainty useful
• Enables overall estimates of uncertainty
• Range of values plus distribution is more useful
  to
• policy makers
• Temporal dynamics
• -Historical data
• -Change data
• -Timing of management events
• may be important

• Tier-specific requirements
• Tier 1 General grassland management
• -Degraded, nominal, or improved
• -Medium or high inputs
• Tier 2 Requires more specific activity data
• -Grazing intensity
• -Fertilization rates
• Species composition, etc. inputs
• Tier 3 Requires model driving data
• Timing of management events is important

10
Available activity data Global

• Global data
• Land use/cover maps
• -DISCover (LANDSAT based) http//edcdaac.usgs.
  gov/glcc/globe_int.html
• -FAO Land use data (survey) http//apps.fao.org/
  
• -Numerous other RS maps
• -Most useful for modeling, but can be used with
  other
• databases to ID grasslands
• Land management databases
• -GLASOD global soil degradation database
• -World overview of Conservation Approaches and
  Technologies (WOCAT)
• Species composition, etc. inputs
• Model-driving data
• -Climate (current/projected) various sources
• -Soils (FAO)
• -Historical land use
• -Potential vegetation

11
Available activity data Regional/national (US)

• Federal Land use/management Data
• Forest service grazing allotments
• Grazing history
• Number of cattle
• Duration of grazing
• Not available electronically
• Bureau of Land Management data
• Rangeland health
• Grazing history
• Grazing allotments
• Not available electronically
• National parks/monuments
• No livestock grazing
• Animal density for select species
• National resources inventory
• Improved/unimproved pasture
• Range condition (collected, but not published)
• Agricultural statistics
• Pasture/range land area by county

• Research networks
• Long-term ecological research sites
• Ag. Res. Service Exp. Range sites
• University Experimental Ranges
• Federal/state managed sites
• USDA rangeland flux net
• NEON new NSF initiative
• CASMGS

12
Available activity data Regional/national
(Other)

• National Land use/management Data
• New Zealand
• Land resource inventory
• National soil database
• Land environments of New Zealand map
• UK
• Network of research sites
• National countryside monitoring scheme
• Rural stewardship scheme
• Not available electronically
• India
• Indian Agricultural Statistics Research Institute
• Research networks for many regions
• Some state-level databases
• Russia
• Ministry of agriculture national land use
  statistics
• Livestock numbers
• Country profiles available from CGIAR -
  http//www.asti.cgiar.org/profiles.cfm

• Research networks
• EuroSOMNET
• Various long-term exp. sites
• Europe, S. America, Asia
• Numerous treatments
• Some are very (!) long-term
• Proposed grassland flux network
• Project specific datasets
• Asia, Africa, S. America
• E.g., conversion chronosequences

13
Available activity data Summary and shortcomings

• General paucity of data
• Very few data available for some countries
• Soil properties
• erosion
• Land management
• Data are non-uniform
• Variability between countries
• Variability likely even w/in a particular
• international database
• Very few management-specific data
• Some data can be derived, but
• No data for some types of management (e.g.,
  fertilization rates)
• Many data not compiled (conservation plans, NRI
  range data, etc.)

• Mismatch between activity and C sequestration
  data
• Usually C seq. data evaluates specific practices
• Such as all of those discussed above
• Activity data much more general
• Data are non-uniform
• Variability between countries
• Variability likely even w/in a particular
  international database

14
Uncertainty contributions from activity data
Developed country cropland
40
60
Activity data
Factor (C sequestration) data
15
New/potential sources of activity data
16
New/potential sources of activity data
H1
Pastures under intensive rotational grazing are
(1) more productive (higher NPP) and (2) have
different seasonal distribution of aboveground
biomass and can, thus, be distinguished from from
extensively managed pastures remotely.
H2
Rangeland sites with similar climate and grazing
history have similar production potentials that
are modified by current grazing intensity which
affects LAI and is, thus, amenable to detection
by remote sensing.
17
Conclusions

• Potential C sequestration in grasslands is
  substantial
• (see Ogle et al. Session 8, grand ballroom 3,
  400 today)
• Activity data are required for assessing either
  actual or potential
• C sequestration rates
• Currently available activity data are limited
• New data are needed for accurate estimates of C
  sequestration
• regardless of Tier/methods chosen
• Estimates of historical grassland management data
  required
• New activity data should align with data needs
• spatially explicit
• accurate
• frequent