Farming as an ecological system and as an economic system.

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Farming as an ecological system and as an economic system

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  • Farming as an ecological system and as an economic system

  • Farming as an ecological system

  • Manipulated ecosystem(Farming)Inputs from the physical environmentSolar energy / temperatureRainfall / moistureTopography / reliefSoilPlant nutrientsInputs from the human environmentLabourCultural valuesTransportPlanting materialsTechnologyGovernment influenceCapital / equipmentAgricultural productsMarketCashWaste productsAgricultural systemsBioticAboticAboticBiotic

  • Components of an ecosystem

  • Three major principles of ecosystemNutrient cyclingEnergy flowStructure

  • Ecosystem - Nutrient Cycle

  • Ecosystem - Energy flowSource: Law (2004)

  • EcosystemNutrient cycling, energy flow and structure

  • Ecological systemManipulated ecosystemFor yields (desired products)Provide the most favourable conditions for the plants and animals he wishes to produce.

  • Agro-ecosystem VS natural ecosystem

    Natural ecosystemAgro-ecosystemInputsPhysical inputsThe SUNPhysical + Human inputsDisposal of outputsReturn to the ecosystemFor saleRoles of manIndirectly affect the inputControl the inputs and processes Nutrient cycling/ Flow of energyContinuousInterrupted with energy subsidy in various formi.e. Chemical fertilizerCrop/ Livestock selection and species diversityHigher biodiversity Larger number of speciesLower biodiversity Monoculture/ PolycultureStabilityStableUnstable

  • Ecological system Energy FlowEnergy efficiency Energy Yield Ratio=energy output / energy input The higher the energy yield ratio, the more the efficient the ecological system

  • Energy efficiency

    Source of EnergyExampleEnergy Yield RatioHigh Energy systemSolar energyVast inputs of fossil fuelsFarms in USA, Western Europe.0.38:1LowMedium Energy systemEnergy input from the sun, wind & use of animalsWet rice cultivation in Asia4:1MediumLow Energy SystemSolar energy mostlyShifting cultivation in SE Asia, Pastoral nomads16:1 High

  • Ecological system Nutrient Cycle

    NaturalAgricultural system

    Nutrients circulate within the ecosystem

    Removed entirely by prolonged cropping without compensating fertilizer inputNutrients are replaced again and again from different parts of ecosystemHeavily subsidized by input of chemical fertilizersUnavailable or accumulate to toxic level

  • Ecological system - Stability

    NaturalAgricultural system Solar energy drive energy flow and nutrients cycle Complex ecological linkages Large biodiversity self-maintained and stable solar energy + human energy inputs Energy flow and nutrients cycle Fewer crops and animals or even monoculture maintained by human effort unstable

  • Farming as an economic system

  • Economic systemInputs as capital and human effortInvestment (inputs)Form of moneyForm of labourOutputs as financial gainFarmers need to make decision about How much to invest and;What aspects they are going to invest.

  • Economic system decision makingKey questionsWhat to produce?How much to produce?How to produce?How much to invest?What to lease?How much to lease?Where and how to buy?Where and how to sell?

  • Economic system decision makingResult of decision by farmersland use, cropping, use of biological inputs, total outputs and farming method and pattern

    Final goal profit satisfaction or maximization?

  • Economic system decision makingReasons:Imperfect information Lack of capital Social customs may work against improvementPersonal characteristicsFarmers are satisfiersFarmers may be conservative and consider a low degree of riskFarmers dont want the extra work and they want to have more leisure time.

  • Decisions result in action which may result in land use patterns, wealth or povertyWealth economic surplus innovation Poverty stagnation

  • Economic system decision makingPapua New GuineaSubsistence economyFarmersMinimum investment (human and cultural inputs)For tribal or village consumptionLocalizeResponse to natural conditions

    AustraliaCommercial economyEntrepreneursHeavy investment (human and cultural inputs)For sale (foodstuff, industry, urban)GlobalizeResponse to markets

  • Shifting cultivation primitive only a small patch of forest is cleared fallow period allow the forest to regenerate and fertility of the land to be restored Poses little threat to ecosystem