Your SlideShare is downloading. ×
0
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Defense of Master's Final Report
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Defense of Master's Final Report

708

Published on

Black Wattle (Acacia mearnsii, Fabaceae) represents one of the most important invasive alien species that have spread over large catchment areas in South Africa, with well documented effects on …

Black Wattle (Acacia mearnsii, Fabaceae) represents one of the most important invasive alien species that have spread over large catchment areas in South Africa, with well documented effects on reducing water yield and in altering indigenous plant structure. Nationwide measures are being applied to eliminate this species, and different protocols are being evaluated for restoring heavily invaded areas, such as the rehabilitation site at the Lower Witteklip River in the Eastern Cape Province.
As a part of the Kouga River Rehabilitation Pilot Project, this study described four topics: (a) the degradation state of the area which was concluded that it was related to the presence of Black Wattle, (b) revegetation practices which were established as an experiment to evaluate the guilds which could be used to rehabilitate similar areas, defining as a priority from the early state of the experiment, to use a vast mix of species and densities as treatments, (c) effects of different biomass loads on burning and on the temperature to which soil was exposed in which it was observed that values dependent on the biomass load and not on the sampling site and (d) an assessment of the effects of fire and transformation of wood to chips, as methods to remove biomass left from clearing from the site which from the data available, there were not a definitive conclusion on which one of the treatments influenced on the results, mainly because of the lack of time for the soil seedbank to be fully germinated, and due to a mistake in the methodology by not segregating between the indigenous species group. This technical report also includes an assessment and some recommendations for the activities applied to the Lower Witteklip Rehabilitation Site and for the experiments.

Published in: Education, Travel
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
708
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
6
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Technical Report of theRestoration of a section of the Witteklip River as part of the Pilot Project for Rehabilitation of the Kouga River
    Master Oficial en Restauración de Ecosistemas
    José David Díaz González
  • 2.
  • 3.
  • 4. Problem:
    Riparian areas invaded
    effects on water yield
    biodiversity loss
    soil degradative processes
    Situation of special concern for the Nelson Mandela Metropolitan Municipality
    Problemdescription
  • 5. Cause of the problem:
    Initial degradation derived from overgrazing
    Current degradation caused by Black Wattle (Acacia mearnsii, Fabaceae)
    Invasive alien plant for South Africa: Transformer status
    Well documented effects on reducing water yield and in altering indigenous plant structure.
    Persistent long-lived seeds favored by fire
    Problemdescription
  • 6. Objectives
    • Of the Kouga RiparianRehabilitation Project
    Defining the most efficient protocol to clear and restore areas invaded with Black Wattle (Acacia mearnsii)
  • 7. Objectives
    • Of the Practicum
    Description of restoration activities in a section of the Witteklip River
    Evaluate the possibilities of using fire or transformation of wood to chips, as methods for the disposal of the Black Wattle residues
  • 8. Sitedescription: General location
  • 9. Sitedescription: PhysicalEnvironment
  • 10. Sitedescription: PhysicalEnvironment
  • 11. The Lower Witteklip Restoration Area:
    Witteklip River, which in turn is tributary of the Kouga river.
    The Kouga River Catchment, represents a key water source for the Nelson Mandela Bay Metropolitan Municipality,
    Sitedescription: Description of theriver
  • 12. Characterization of studysite:Longitudingalprofile of the Witteklip River
  • 13. General dyagnoseforthestudysiteProtocol for the Evaluation of the Ecological Status of Mediterranean rivers (RBP)
    extremely degraded site with a very low quality
    Site can have a partial success in holding aquatic biota with the initial situation observed
    QBR index: evaluate riparian quality
    IHF index: physical habitat
  • 14. General diagnose for study site: Digital image of site, 2001
  • 15. Review of the clearing and rehabilitationactivities in the study site
    • Clear-cutting all Acacia mearnsii trees
    • 16. Application of herbicides to suppress resprouting
    • 17. Wood stacks piling and drying for 3 months
    • 18. Biomass burning
    • 19. Restoration of plant cover
    • 20. Restoration
    • 21. Management of seedbank
  • Experiments performed:Biomass burning
    Assessment of temperature in first 5 cm of soil:
    Soil-stored seed banks in fynbos tend to be concentrated in the upper 3–5 cm of the soil
    What temperatures are reached under different conditions of biomass loads?
    Labels with temperature sensitive paint.
    Color changes permanently when exposed to heat for more than ten minutes
    Sets placed at: Surface, 2 cm, 5 cm
  • 22. Results: Biomassburning
  • 23. Discussion: Biomassburning
    Fuel load - temperature
    Influence of depth
    Highest temperature peaks
    High temperatures more likely to happen in the surface.
  • 24. Experiments assisted:Revegetation
    • Identify species or guilds and densities which would effectively restore the ecological functions for invaded areas
    • 25. 98 planting plots divided into two sub-plots: Burned and not burned
    • 26. Treatments:
    • 27. Control
    • 28. High density planting
    • 29. 9 plants/m²
    • 30. Low density planting
    • 31. 4 plants/m²
    • 32. Seeding and planting
    • 33. Eragostistef sowing
  • Revegetation:Distribution of paired plots
  • 34. Revegetation with a mixture of native species selected by the R3G researchers under several considerations:
    Species from surrounding, uninvaded reference sites
    Species whose seeds could be collected, propagated and established well with relative ease:
    Species that would grow quickly: this would potentially suppress alien recruitment.
    Species that will provide good ground cover: This selection criteria considers the risk having bare ground exposed to erosion.
    Revegetation:Criteria for species selection
  • 35. Revegetation:Conditions recommended for planting riparian vegetation in alien invaded fynbos
  • 36. Experiments performed:Management of seedbank
    Comparison of two methods to eliminate unwanted biomass left after large scale
    Black Wattle clearing:
    Burning
    transformation to wood chips,
    What happens to the seedbank?
    From Black Wattle?
    From the other species?
  • 37. Results: Management of seedbank
  • 38. Results: Effects of soil preparation methods on soil seedbank
  • 39. Results: Management of seedbank
    Estimated germination means for Black Wattle and the other species group, separated by temperature range.
  • 40. Discussion: Management of seedbank
    Germination of Black Wattle increased with the burned treatment
    Control and wood chips treatment: almost no germination
    Other species group, germination was observed but low in wood chips and control.
    Not possible to define if germination in the controls section (sand control, wood chips control) was a result of the presence of seeds in the sand control or in the wood chips
    Results dependant on:
    the treatments
    low seed rain
    depletion of surface seedbank
    not enough time for germination
    Similar experiments: final results in 12 months
  • 41. Black Wattle:
    Reduced presence of indigenous species in the study site
    Decreased the quality of the riparian vegetation which was almost absent
    Fell and Burn method,
    Possible outbreak of Black Wattle with few indigenous species present
    Conclusions
  • 42. Soil temperature:
    Surface temperature
    Large logs on wood stacks
    Soil seedbank
    Germination of Acacia mearnsii
    Germination of other species
    No separation between other species, did not allow to define groups of species, families or plant growth forms
    Unclear which treatments influenced on the results obtained.
    Time for experiments, was not enough
    Conclusions
  • 43. ¡Muchas gracias!

×