Sustainable Agriculture &

Forestry

AGRICULTURE transforming natural ecosystem into one

devoted to production of food, fibre, & fuel

Requirements: huge amounts of land, water, energy genetic modification of plants and animals manipulation of resources and species

interactions

Advancements become more

productive world food production

kept up with rapid population growth

main livelihood of 40% of earth’s pop’n

provides both food and jobs/income

Environmental Costs reduced biodiversity destroyed natural ecosystems polluted/reduced freshwater ecosystems energy consumption greenhouse gas production major climate change contributor

Earth’s Land Resources ~ 37% Earth’s land used for agriculture 1/3 of this used for crops rest used for pastureland

not all land equally productive less productive areas require more

technology and inputs (eg fertilizer etc.) agriculture competing for space with

housing/businesses in developed countries land being deforested for agriculture in

developing countries

Agriculture

Productivity How much food/plants can be grown on a

certain area of land (hectare/acre)Differs widely depending on: soil water nutrients climate crop varieties energy

SOIL 1000’s of different types of soil depends on age, location, climate,

organisms living in it…

Soil CompositionMixture of: organic material from decaying plants and

dead organisms minerals from weathering and erosion of

rocks all soil different depending on type of rock,

plants, and climate of the area

Soil Profile5 Soil Layers (Horizons)

1. O Horizon (Litter) decaying organic matter releases

nutrients into soil usually darkest layer

2. A Horizon (Topsoil) 20-30 cm thick provides plants with nutrients rich in humus (decomposing plant

material) allows air and water to move

through soil

3. B Horizon (Subsoil) mix of rocks and humus roots can get some water from

groundwater4. C Horizon combination of weathered rock

and soil5. Bedrock – layer of solid rock under

soil

2c_soil_formation

Classifying Soils1. Texture: based on size of the particlesClay – many small, tightly packed particles,

little room for air, water or rootsSand – many large particles, lots of aeration,

too much water drains throughLoam – equal mixtures of sand and clay,

ideal since holds both air and waterYouTube - Soil Texture - Environmental Science

stored in soil for plant growth helps diffusion of gases, conduction of heat, and

the movement of nutrients moisture can be improved by improving the

aeration (air in soil)

3. Aeration plants (and microbes) require air to live compacted soil kills microbes and

decomposition of organic material slows fewer nutrients for plants toxins build up in soil and plants

2. Water

Non-mineral requirements: carbon, hydrogen & oxygenMacronutrients: nitrogen, phosphorous, potassium, calcium, magnesium, &

sulphur Fertilizers: can control nutrients usually contains 3 numbers referring to

the proportion of N, P, & K Ex Bone Meal – 4,12,0 nitrogen promotes lush green growth phosphorous promotes the growth of many flowers potassium promotes root growth (adds hardiness)

4. Required Nutrients

5. Acidity pH indicates the acidity or alkalinity of soil pH under 7 = acidic pH over 7 = alkaline (basic) most crops require soil between 6-7 pH acidity can occur naturally also because of use of nitrogen fertilizers,

manure, and acid precipitation acidic soil can be treated with lime or calcium to

reduce acidity alkaline treated by adding sulphur

Regi’s Gardens1.Russell St DoorsREGIS\Regis 5 of 5 P.pdfConditions: north facing moist/damp

Plants: Sedge grass – shady areas Royal fern – damp & shade Hostas – shady areasREGIS\Regis Photo Raised Grdn.jpg

2. Beside Stairs to FieldREGIS\Regis 4 of 5 P.pdfConditions: north facing under trees weedyPlants: sedge grass hostas bugle carpet – ground cover, partial shadeREGIS\Regis Stairs.jpg

3. Next to Sports FieldREGIS\Regis 3 of 5 P.pdfREGIS\Regis 2 of 5 L.pdfConditions: west facing full sun next to concrete wall and pavement - hotPlants: blue oat grass – hot weather, drought tolerant sedums –drought tolerant, grown in poor soils spurges – dry poor soil spiderworts – full sun, dry conditions

REGIS\Regis Fence.jpg REGIS\Regis Eco Plants.jpg REGIS\Regis Grd East Drs.jpg

4. Window GardensREGIS\Regis 1 of 5 L.pdfConditions: under roof – little rain trampled by fans watching games poor gravelly soil very dryPlants: spurges sedums rock wall to prevent tramplingREGIS\Regis Photo Window Grd.jpg