Ecosystem components

1
Ecosystem components

• Abiotic components
• soil factors root anchorage, provide water and
  nutrients for plants, niche or habitat for plants
  , microorganism and animals
• climate factors
• Biotic components
• primary producers
• consumers
• decomposers

2
Ecosystem function

• Energy flow follows the thermodynamics law ie.
  energy can be neither created nor destroyed, only
  change in form.
• Nutrients cycling

3
The losses of energy as it moves through trophic
levels
Heat
comsumed
comsumed
Heat
Biomass produced at 1st trophic level
comsumed
Heat
2 nd trophic level
3 rd
4 th
Producer
1st consumer
2nd consumer
4
Succession, Competition and Climax

• Succession of pasture or rangeland series of
  change and dynamic of the component plant species
  through the changes in abiotic factors
  (particularly soil factors)
• Competition process which occures when two or
  more organisms are making common endeavor to gain
  one or more requisites in excess of the
  immediate supply
• Climax final state of succession at which
  components of the community is stable in function
  or at a dynamic equilibrium

5
Ecology of the pasture

• Components
• climatic resources
• land resources
• plant (forage crops) resources
• animal resources
• human and social resources
• Pasture ecosystem

6
Dynamics of the pasture

• Nutrients cycling
• Water cycling
• Species components
• Utilization pressure
• animal management
• stocking systems
• conflict in landuse

7
Availability of nurtrients to plants
Rocks parent materials
Minerarisation
Mobilization
Organic form Unavailable nutrients
Inorganic form Available nutrients
Immobilization
8
Sources of nutrients in pasture ecosystems

• Parent materials
• Return of excreta
• urines N P
• dung K
• Fertilizer
• Supplement feeds
• Atmosphere N2

9
Yield and nutrient yields of grass sward with
return of excreta

• Treatment DM N P K
• (kg/ha)
• Concentrate
• Excreta return 6233 132 22.2 161
• No return 4794 106 19.4 107
• Dung 35.6 19.8 19.4
• Urine 69.7 0.1 99.5
• source Mott, G.O. 1970. Nutrients recycling in
  pastures. in D.A. Mays ed. Forage Fertilization.

10
How the fertilizer will affect on the nutrient
pool

• Rate of application
• Kind of fertilizer
• Frequency of application basal, top dress
• Management of the pasture grazing or cut
  carry
• Accerelating factors stocking rate, soil fauna
  micro-organism

11
Supplement feeds

• Concentrates
• protein source soybean meal, fish meal, rubber
  seed meal, rice brand
• carbohydrate source cassava, corn, broken rice
• vitamin minerals
• Conserved feed cut grass, agricultural wastes
  or industrial by-product

12
Atmosphere

• NH4, NO3, NO2 , SO4 and dust in rain
• Symbiotic N2 fixation by Legume Rhizobium spp.
• Non synbiotic N2 fixation by Clostridiun,
  Azotobacter, Beijerinckia, Derxia spp.

13
Nitrogen cycle
N2 fixation
N2
Rhizobium
Plant biomass
grazing
Denitrification
Animal biomass
Microbial biomass
Plant assimilate
Heterotrophic microbial assimilation
NO3
Organic N Humus
Nitrification
NH4
Mineraization
14
Nitrogen cycle in the components of grassland
Feed
Plant products
Animal products excreta loss
Plant biomass
Animal biomass
Microbial biomass
Organic soil pool
Leaching gas loss
Inorganic soil pool
Fertilizer
15
Animal Products
Fertilizer input
Animal growth
Animal excreta
Soil nutrients
Fertilizer economy in managed pasture
16
Water cycle
Precipitation
Transpiration
Evaopration
Foliar absorption
Soil water
Infiltration
Leaching / run off
17
Succession in pasture(dynamic of botanical
composition)

• BC vs grazing
• selective grazing
• palatability
• resistance to grazing pressure
• BC vs fertilizer input
• fertilizer requirement (P, N availability for
  grasses and/or legumes)
• BC vs climatic conditions
• drought and floods conditions

18
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• ????????????????????
• ?????????????
• ??????????????? ???? ????? ??
• ????????????????????
• ???????? ????????? ??????????????????????????
  ???????? ??????????? greenhouse effects (methane
  gas release)
• ?????????????????????????????????
• ?????????????????????????? ?????????

19
??????????????????????

• ??????????? Animal production
• ???????????? ????????? Recreation
• ?????????????? ?????? Soil and water conservation
• ??????? ???????????????? Wildlife habitat
• ????????????????? Plant genetic resources

20
Grassland types

• Temperate zone
• Humid temperate pastures
• Semi arid temperate pastures
• Mediterranean pasture (winter rainfall)
• Sub-tropical pastures
• Tropical zone
• Humid tropical
• Savannah
• Semi arid tropical pastoral
• Arid tropical pastoral

21
???????????????

• ???????????????? Natural grassland, Rangeland,
  Savannah grassland
• ?????????? Imperata cylidrica
• ???????????? Arundinaria pusilla
• ??????????? Themeda triandra
• ???????????????? Heteropogon contortus
• ?????????????????????? Chrysopogon orientalis
• ???????????? Ischaemum aristatum
• ???????????????? Panicum repens, ???????????????
  Hymenachne pseudointerupta

• ????????????????? Man made pasture, Managed
  pasture or grassland e.g..
• Brachiaria mutica, Brachiaria ruziziensis,
  Panicum maximum, Paspulum plicatulum, Pennisetum
  purpureum, Stylosanthes hamata

22
???????????????????????? ???????????

• ?????????????????????? Grazing reserved,
  Communial grassland
• ?????????????????????? ?????????????????????
  Shifting or swiden cultivation
• ????????????? ????????????????? Along roadside
  and lakeside
• ??????? ????????????????????? Reserved forest or
  National park
• ?????????????????

23
????????? ??????????????????????????????

• ?????????
• ???????????
• ???????????????????????????????????????
• ???????????? ?????????????? ?????????????????????
• ?????????????
• ???????????????????????????? ????????????????????
• ?????????? ???????????? ???????????
• ?????
• ????????????????????????????? ???????????????
• ??????????????????? ???? ????????? ??????????
  ????????????????
• ?????????????? ??????

24
Grassland management concepts

• Goals
• ecological stability
• sustainable yield
• Management
• carrying capacity utilisation / supply
• stocking rate and grazing pressure
• nutrients and water cycling
• trophic level and food chain
• Other purposes of landuse
• resources allocation
• man and community

25
Common area to be used by anyone who wishes
Lot of grass and timber to be used , I just
increse my cows
Tragedy of common properties
26
Bibliography

• Holecheck, J.L., Pieper, R.D. and Herbel, C.H.
  1989. Range Management Principles and
  Pracitces. Prentice Hall. Englewood Cliffs 501
  pp. (SF85 H64 1989)
• Jones, M.B. and Lazenby, A. 1988. The Grass Crop
  The Physiological Basis of Production. Chapman
  and Hall. London 369 pp. (SB197 G77 1988)
• Mack, S. 1990. Strategies for Sustainable Animal
  Agriculture in Developing Countries. FAO, Rome
  271 pp. (SF75.2 S77 1990)
• Morley, F.H.W. 1981. Grazing Animals World
  Animal Science, B1. Elsevier Scientific
  Publishers Co., Amsterdam 411 pp. (SF85 G72
  1981)
• Roux, E. 1969. Grass A Story of Frankenwald.
  Oxford University Press. London 212 pp.
  (QH541.5P7 R68 1969)
• Snaydon, R.W. 1987. Managed Grasslands Analytical
  Studies Ecosystems of the World 17B. Elsevier
  Scientific Publishers B.V., Amsterdam 285 pp.
  (SB199 M35 1987)
• UNESCO. 1977. Tropical grazing land ecosystems.
  UNESCO/UNEP/FAO. Mayenne. 655 pp. (QH541.5 U57
  1977)