Methods of vegetation sampling:

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• Methods of vegetation sampling
• http//www.blm.gov/nstc/library/pdf/samplveg.pdf
• http//www.blm.gov/nstc/library/pdf/MeasAndMon.pdf
  
• Range cover types of the US
• ftp//ftp-fc.sc.egov.usda.gov/GLTI/technical/publi
  cations/cover.pdf
• Ecological site inventory technical reference
• http//www.blm.gov/nstc/library/1734-7direct.html
• Indicators of rangeland health
• http//www.blm.gov/nstc/library/pdf/1734-6.pdf

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Seminars

• EECB seminar Thurs 400 PM OSN 120. Dr. Larry
  Stevens, Grand Canyon Wildlands Council.
  Biogeography of the Grand Canyon, and Colorado
  River Management.

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Reading

• Textbook Chapter 12 and 13
• Sparrow, A., M. Friedel, and D. Tongway. 2003.
  Degradation and recovery processes in arid
  grazing lands of central Australia part 3
  implications at landscape scale. Journal of Arid
  environments 55 349-360.

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Outline

1. Case study identifying communities and relating
   to environmental conditions
2. Student case studies
3. Productivity plants and ecosystems
4. GPP, NPP, and Efficiency
5. Global and environmental patterns of NPP
6. Production in forest VS rangeland
7. Factors influencing productivity fire,
   herbivory, nutrient pulses, etc.
8. Climate change, CO2 accumulation, and carbon
   sequestration

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Species interactions and restoration

• Rangeland in Kenya high productivity, high
  rainfall (600mm/yr).
• Massai traditionally nomadic pastoralists but now
  becoming sedentary.
• Can no longer move when pasture bad must use
  land stewardship.
• Land highly overgrazed, and desertification
  widespread (80?).

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Fertile islands?

• Aloe secundiflora shrubs have vegetation around
  them even in eroded areas
• Aloe is unpalatable as an adult
• Positive effect appears to extend beyond range of
  aloe canopy
• Potential facilitation effect?

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Theory of facilitation

• Presence of one plant species enables others to
  persist
• One species ameliorates environment facilitation
  important in harsh conditions.
• Positive environmental effects outweigh possible
  negative competition effects
• This may switch with plant life stage (e.g.
  facilitate as seedling, compete as adult)

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Additional Value of Aloe?

• Aloe is a medicinal plant poached from the
  wild for sap
• Massai ranchers need cash rather than cattle
• If planting aloe can facilitate range recovery,
  is this a win-win situation for Massai?

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What ecological interactions/processes need to be
considered?
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Aloe as facilitator

• Quantification of spatial pattern (circumstantial
  evidence)
• Basic experimentation on species interactions
  (does aloe facilitate other species?)
• Establishment of dryland agriculture and range
  restoration program
• Work by Elizabeth King, UC Davis

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Aloe as facilitator

• Quantification of spatial pattern (circumstantial
  evidence)
• Spatial pattern aloe plants retain soil, have
  higher soil fertility, more litter, greater soil
  seed bank, higher cover and diversity of
  surrounding vegetation. Soil retention

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Aloe as facilitator

• Quantification of spatial pattern (circumstantial
  evidence)
• Basic experimentation on species interactions
• Plant Aloe, compare to thorns (grazing
  protection) and control (soil disturbance)
• Plant Cenchrus cilliaris, observe growth.
• Cenchrus growth substantially enhanced by Aloe,
  effect extended away from plants

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Aloe as facilitator

• Quantification of spatial pattern (circumstantial
  evidence)
• Basic experimentation on species interactions
  (does aloe facilitate other species?)
• Establishment of dryland agriculture and range
  restoration program
• Growing and planting Aloe and Cenchrus on Massai
  group ranch hope to harvest Aloe sap as cash
  crop and graze between rows.

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Your turn

• List management issues/projects you know of in
  range and forest ecosystems.
• Which of the ecological processes or interactions
  we have discussed so far do you need to
  understand?
• Can you make predictions or recommendations based
  on your understanding of the ecological systems?

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Future lectures

• 10 minutes at beginning of class for students to
  present case studies pertaining to previous
  lectures topic.
• Start Wed topic is measurement and definition
  of communities

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Community working definition

• Two concepts continuum or community type
• Continuum vegetation changes along gradients of
  environmental conditions. Species may co-occur by
  chance/shared environmental tolerances.
• Community type species occur in association,
  such aggregations have adaptations holding them
  together as units. Show boundaries between them.

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Community working definition

• These two concepts are not mutually exclusive
  both patterns occur to a greater or lesser extent
  in natural vegetation. Sharpness of community
  boundaries often relate to abrupt changes in site
  conditions (e.g. serpentine soil patch).
• Community best thought of as a level of
  organization rather than a distinct entity with
  boundaries.

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Community working definition

• Visually distinct features of a landscape.
• Interpreting composition, stand structure,
  dynamics, and spatial distribution requires
  understanding of site conditions, disturbance,
  history, and ecological processes. Barnes et al
  1998.
• Forest type a community defined solely on the
  basis of canopy species
• Ecotone transition area between two community
  types. e.g. grassland and forest broad change
  in community due to longer term
  climate/environment BUT exact position of
  treeline depends on local disturbance,
  competition, history, etc.

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Community attributes

• Physiognomy
• Architecture, LAI, life-forms, phenology, etc.
• Composition, spatial pattern, and diversity
• Nutrient cycling
• Demand, storage, rate of cycling, efficiency
• Productivity
• Control of environment
• Plant-environment feedback
• Change over time
• Succession, stability, migration

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Community structure

• Physiognomy physical structure of vegetation
  (appearance, structural complexity, architecture,
  growth forms)
• Why is vegetation structure important?

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Community structure

• Leaf Area Index LAI.
• Square meters of leaf area per square meter of
  ground.
• Higher LAI, usually more sunlight intercepted,
  greater efficiency and productivity. e.g.
  tropical forest LAI11, uses 1.5 incident
  radiation, desert LAI1, uses 0.04 incident
  radiation.

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Life forms

• Characteristic structure of plantlife form will
  affect disturbance tolerance, physical structure,
  regeneration, etc.
• Raunkiaer (1934) classified plants based on
  location and protection of meristems and/or
  reproduction (see handout).

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Community composition

• Communities composed of species are all species
  necessary to define a community?
• Biodiversity
• What is biodiversity?
• What does diversity signify? Why is it important?
• Types of diversity richness, evenness,
  functional diversityothers?

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Patterns of diversity

• Species and individuals distributed in different
  ways in different communities.
• Spatial patterns
• alpha diversity diversity or richness in
  species within a habitat
• Beta diversity diversity of habitats in an
  area species turnover
• Gamma diversity diversity of a region

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Upcoming lectures

• Next lectures will address aspects of communities
  and diversity concepts
• Mar 3 productivity
• Mar 8-9 plant-soil interactions, nutrients
• Mar 10 disturbance and succession
• Mar 22 state and transition dynamics
• Mar 24 fire ecology and climate change
• Mar 29 functional groups and biodiversity

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Example of community description

• Ecological sites BLM, USFS, and NRCS
• Used for both range ecological sites and forest
  ecological sites.
• Details of range site description given in
  handout
• Details of forest site description given in
  national Forestry Manual
• ftp//ftp-fc.sc.egov.usda.gov/NSSC/
  National_Forestry_Manual/2002_nfm_complete.pdf
• Range and forest type sites are differentiated by
  HISTORIC VEGETATION.

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Ecological site

• Definition A distinctive type of land with
  specific physical characteristics that differs
  from other types of land in its ability to
  produce a distinctive kind and amount of
  vegetation.
• Clementsian?

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Ecological site description

• Vegetation is product of
• Soils
• Topography
• Climate
• Disturbances
• Differentiated by
• Differences in dominant plant species
• Changes in proportion of plant species
• Changes in productivity

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Ecological site description

• Utility of site descriptions
• Rangeland landscapes are divided into ecological
  sites for the purposes of inventory, evaluation,
  and management