rural energy and land degradation major source of energy: crop (human) fodder (animal) fossils fuels...

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Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) • Fossils Fuels (coals, crude oil, natural gases) Electricity; generated in hydro-station fossil fuelled • Nuclear • Solar • wind Biomass (fuel-wood, crop residues, dung, biogas)

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Page 1: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Rural energy and land degradation

• Major source of energy:• Crop (human)• Fodder (animal)• Fossils• Fuels (coals, crude oil, natural gases)• Electricity; generated in hydro-station fossil fuelled • Nuclear• Solar • wind• Biomass (fuel-wood, crop residues, dung, biogas)

Page 2: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Rural energy

Traditional or non-commercial fuel include:• Fuel-wood• Animal dung• Stove• Charcoal• Crop residues• Biogas• Solar (direct sun energy)• Human energy• Draught animal

Page 3: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

• 1/3 of all energy consumption in China derives from the non-commercial fuels

• ½ India

• ¾ Bangladesh

• 90% or more in SSA

Page 4: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Rural demography

• Majority low income countries population live in the rural areas – >90% in SSA– 4/5 in China and India– some 60% in Turkey

Page 5: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Rural energy major role

• Crop for human food

• Fodder for draught animal

• Cooking => 50% of total HH use

• Space heating => 30%

• Light

Page 6: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

..Cont

• 15% - 20% for non-hh use

• Insect control

• Fruit and crop sun dried preservation

• Bricks and tiles production

• Cement and metal industry

• blacksmith

Page 7: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Contribution of Various Sectors to African Woodfuel Consumption for Different Reference Years (Million m3)

Year 1980 1985 1990 1994

Households 461.9 489.1 520.2 537.2

Industries 37.0 42.3 49.8 59.4

Page 8: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Fuel-wood contribution

• Fuel wood => 80% of rural HH energy– Cooking– Heating

• While charcoal – rural industry role

Page 9: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Contribution of Various Types of Woodfuels to African Woodfuel Consumption (million m3)

Year 1980 1985 1990 1994

Fuelwood 435.5 458.1 480.4 507.0

Charcoal 76.5 89.0 108.5 113.0

Page 10: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

• (FAO), estimates that 37000 square kilometers of Tropical African forest disappear every year through forest clearing.– > Human popl. food production (agriculture)– Draught animal fodder – Fuel-wood

• Deforestation rate exceeds planting rate 29:1• 9 decades productive forests are expected to be

depleted.

Page 11: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Woodfuel Consumption According to the Best

Estimates* in Different Continents (1000 m3)

•   •    1980 1985 1990 Average annual

growth rate1980-90

Europe and non Europe OECD 451 504 488 0.8 %

Africa 514 549 592 1.4 %

Asia 636 711 788 2.2 %

Page 12: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Contribution of the Top 10 countries to African

Woodfuel Consumption in 1994 Rank Country 1000 m3 (%) of total African Consumption

1 Nigeria 118.8 19.1%

2 Ethiopia 56.6 9.1%

3 South Africa 42.5 6.8%

4 Tanzania 42.2 6.6%

5 Congo Democrat. Rep. 38.0 6.1%

6 Uganda 29.8 4.8%

7 Kenya 28.7 4.6%

8 Sudan 26.3 4.2%

9 Mozambique 21.7 3.5%

10 Cote d'Ivoire 19.0 3.0%

  Total 422.6 67.8%

Page 13: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Impact on environment

• Land is terrestrial bio-productive system that comprises:

• Soil• Vegetation• Other biota and,• Ecological and hydrological process that

operate with the system.• Any one of these components can be

affected by climate and/or human activity.

Page 14: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

• Human activity– Over-cultivation– Overgrazing– Deforestation– Poor irrigation

• Climate – Prolong drought

Page 15: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

• These are excessive pressure on resources ecosystems, fuelled by local forces– Increase in human popl.– Escalation of human needs– Poverty– Land shortages – Landlessness – Wars– Poorly conceived national policies (export production

vs crop production for local use)– Global economy– Debt burden

Page 16: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

• SSA popl. *2 in the past 30 years => 708M (1994) & continue to expand;rate of 3%/yr

• Every year 21M people need food• Thus, > density + > popl. growth + rapid

urbanisation necessitate more land for crop production, fodder for draught animal, more wood for fuel.

• Over exploitation of land, forest, and pasture via over cultivation, overgrazing and deforestation will inevitably lead to soil erosion, i.e. land degradation.

Page 17: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

• degradation = diminution or distraction of biological potential.

• Process of land degradation:– Long term distraction of vegetation– Diminution of many plants & animals popl.– H2O erosion– Wind erosion

• Soil erosion is believe to > in area, with little or no vegetation cover; e.g. maize yield have < from 6.5 t/ha to 1 t/ha due to erosion &/or loss soil fertility- Nigeria

Page 18: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Forest role

• Cumulus cloud are formed due to upward mvt of air (over forest) => start rain.

• Forests trap precipitation like fog, cloud & moisture.

• High permeability of forest soils enhances moistures balance and < risk of catastrophic floods

Page 19: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Org.M. & Humus role

• Organic matter helps hold the soil in place (vs rainfall & wind blows).

• Humus helps the soil to absorb and store water.

• Tropical soil appear to be thin & once exposed to the burning sun and rain => prone to erosion and loss of their structure and fertility.

Page 20: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

• Live tree branches, shrubs and grasses were cut for fuel =>rob soil from protective & organic matter.

• Uproot crop residues for fuel after harvest have also contributed to degradation.

• Costly diversion of animal manure from food production (fertilizer) to cooking.

Page 21: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

Manure and L. degradation

• Only in India 60 t. of dry animal dung is burned per year => robbing farmland of highly needed nutrients and organic matter.

• Loss nutrient, accounting to 1/3 of annual chemical fertilizer use in India.

• Thus damage to soil structure increases as the humus, organic matter and soil organisms which lives in it, play the role of preserving soil structure and fertility needed for production farming.

Page 22: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

• Increase efficiency of energy use rather than energy supply

• Wood stove implementation =>40% to 50% energy saving than open fire with 60% smoke reduction.

• (-)ve, less heat and light• Require small pieces of fire (labour intensive)• Unsuitable for the local pots (problem of culture)

Page 23: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

The substitute should be!?

• Technically efficient

• Finely viable

• Economically profitable

• Culturally acceptable

• Environmentally benign

Page 24: Rural energy and land degradation Major source of energy: Crop (human) Fodder (animal) Fossils Fuels (coals, crude oil, natural gases) Electricity; generated

summary

• Trees for fuel-wood and expansion of subsistence agriculture // to an ever > human popl. appears to lead to deforestation and subsequent land degradation.