Mission 2006 - Jonathan Rhodes (Land): Research (October 1 - October 6)

  • 12.000 Review - December 10th, 2002

  • Amazonian Land Characterization: Part 2 - Group Cohesion - October 31st, 2002
  • Characterizing the Land of the Amazon Rainforest - October 24th, 2002
  • Reforestation Strategies and the Soil: Restoring the Amazon Rainforest - October 16th, 2002
  • October 6th, 2002
  • October 1st, 2002

    October 6th, 2002

    The Information Below References to "Reforestation Basics" - Small Woodlands Program of BC

    Note: This document outlines reforestation strategies for a “small woodlands program.” The compatibility with a large-scale program such as one that would be needed in the Amazon is questionable.

  • Reforestation – revival of forest following a disaster, disease, or logging.
  • Afforestation – creation of forest on farmland, pasture, etc.

    Note: Science of “silviculture.”

    Assessment Key Parts:
    • “Soil characteristics” - chemistry, density, particle size, etc.
    • “Drainage” systems
    • “Nutrient status and capability”
    • Hazards and concerns (i.e. Fires)

    Species Selection Key Parts:
    • “Shade tolerance”
    • “Growth rates”
    • “Elevation range”
    • “Site preference”
    • Current species
    • Maturity of land (i.e. Biome status)
    • Projected use of land


    1. Natural Regeneration
      • Relatively inexpensive (i.e. Seed stocks)
      • Species are already adapted to site
      • May require significant effort to ensure proper growth of forests, planting of seeds, etc.
    2. Artificial Regeneration I – Direct Seeding
      • (My definition) The planting of seeds into the ground in a specific pattern to ensure the maximization of resources and nutrients, to ensure the most productive and successful regeneration of the forest structure, and to create the most economically worthwhile land.
      • Control on what is planted where, etc.
      • (Possibly) More effort required to maintain success of regrowth if trying to maintain a specific focus and goal
      • Cannot account for “predators such as rodents, birds and insects,” which “can drastically affect the regeneration success.”
    3. Artificial Regeneration II – Planting
      • (My definition) The planting of young trees into the ground to expediate the reforestation of the forest in a productive and efficient pattern.
      • Control on what is planted where, etc.
      • Head-start on forestation (one to five years depending on the age of the planted saplings)
      • Significant planning required – stock must be grown similar to natural conditions in anticipation of future requirements
      • Expensive – significant resources required to first plant the seedlings, and then monitor them on a regular basis for health and growth

    Site Preparation Strategies:

    Note: All of the strategies below can be referred to collectively as “mechanical site preparation” - i.e. Preparing a site for reforestation using hand tools, mechanical equipment, chemicals, etc.

    1. Scarification
      • Heavy chains dragged behind a skidder to expose fresh soil.
      • (Possibly) Allows for easier absorption of nutrients.
      • Best for large flat areas.
      • Risks compaction of soil, therefore making nutrients harder to absorb, and roots harder to develop.
      • Note: Due to the lack of topsoil in the Amazon, this method could have devastating consequences on the fertility of the land. As well, any remaining carbon dioxide reserves in the soil would be effectively released into the atmosphere, which would probably not be a good thing....
    2. Burning
      • “Removal of debris”
      • “Reduction of fire hazard”
      • “Removal of pests and competing vegetation”
      • “Exposure of mineral soil”
      • Risky – could end up destroying the nutrient base it is trying to expose
      • Note: In the Amazon this seems like a particularly bad idea. First, there are not many nutrients in the soil to begin with, so burning could effectively leave the land completely infertile. Second, without responsible use and monitoring, this technique could lead to (and has in previous years lead to) serious and uncontrollable wildfires.

    The Above Information References to "Reforestation Basics" - Small Woodlands Program of BC

  • Below References to "Ecological Impact of Tropical Pastures and the Potential of Forage Plants for Sustainable Land Use Systems in the Tropics: An Annotated Bibliography"
                                           - A. Christinck, K. Probst, and R. Schultze-Kraft

    - “Highly-weathered,” “low-activity clay soils” such as Ultisols, Oxisols and Alfisols seem to be prominent on tropical rainforest and the main soil types farming is attempted on in the tropics.

    - Ultisols and Oxisols: acidic, leached, “low cation exchange capacity,” “very low inherent fertility,” “nutrient deficiencies” (N, P, K, Ca, Mg, Zn), “nutrient imbalances” (Al, Mn)

    - Alfisols – less acidic -> “high base saturation,” low nutrient (S, N, K, P, Zn), “low structural stability”

    - Regeneration of fertility through trees/vegetation during fallow periods has been reduced with greater demand on the land.

    - Chemistry:

    • Nitrogen – expensive to produce
      • legumous plants – symbiotic nitrogen fixation
      • symbiosis between grasses/bacteria

    MAJOR POINT: “In low fertility soils, nutrient cycling is an important basis for sustainability. It is the main reason why acid, infertile Oxisols and Ultisols are able to support exuberant tropical rainforest vegetation in udic environments.”

    Above References to "Ecological Impact of Tropical Pastures and the Potential of Forage Plants for Sustainable Land Use Systems in the Tropics: An Annotated Bibliography"
                                           - A. Christinck, K. Probst, and R. Schultze-Kraft

    October 1st, 2002

    • Well, first off (wonder of wonders), it appears that old growth forests are more effective carbon sinks than new growth forests. (article) As this article states, research shows that no matter how aged old growth forests are, they continue to absorb an excess of carbon dioxide. Althoug new "fast-growth" tree plantations (i.e. Eucalyptus) may be effective as temporary sinks, they "may reach a climax state in a matter of decades." Beyond this, the new growth forests cannot account for the carbon dioxide reserves that old growth forests store in the soil (from decaying leaves, roots, etc.) over the centuries. These reserves are disrupted during deforestation, causing a massive release of carbon dioxide into the atmosphere, that would take decades to reclaim and restore.

    • Below are some materials which I have not been able to research in depth, but of which I can give a brief description:

      • PDF - A document that outlines the "ecological impact of pastures and forage plants in tropical land use systems." It appears that this document will be a substantial resource for the biological, physical, and chemical components of soil as well as "erosion control," "nutrient cycling," and soil restoration principles.

      • PDF - This document appears to outline some research into the suitability of certain tree species (about 20 different species) for reforestation strategies. Note: This document refers to reforestation in Panama, but may be applicable to the Amazon.

      • PDF - I'm not entirely sure what this document is (besides a 421-page Congress Scientific Committee [?] PDF file on forestry and science), but I did see topics on reforestation and soil chemistry. This looks like it may be a very "scientific" reference.

      • PDF - Again, I'm not sure about the relevance of the contents of this document. Apparently, it's sort of a transcript of a "Convention on Biological Diversity," with its "main theme" being "forest biological diversity."

      • PDF - This document evaluates "nursery" and reforestation strategies as applied in Costa Rica, complete with statistics and all. :-D A comparison between the Amazon and Costa Rica could make this a valuable resource.

      • PDF - Well now, if this doesn't take the cake, I don't know what does. What could be more useful than a 16-page PDF file titled "Reforestation Basics?"

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