Botswana JCE Agriculture (Syllabus 16) flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

Agriculture

The science and practice of cultivating soil, growing crops and rearing animals for food, fibre and income, comprising crop production, animal production, horticulture and agricultural engineering.

Semi-arid climate

A climate with low and erratic rainfall, high evaporation and a short growing season; Botswana's rainfall ranges from about 650 mm in the north-east to under 250 mm in the south-west.

Hardveld and sandveld

Botswana's two main agro-ecological zones: hardveld is the eastern belt with more clayey, fertile soils and arable farming; sandveld is the sandy Kalahari region used mainly for livestock.

Soil profile horizons

The vertical layers of soil: O organic litter, A humus-rich topsoil, B subsoil of accumulated clay or iron, C weathered parent material and R bedrock.

Soil texture

The relative proportions of sand, silt and clay particles in a soil; texture determines water-holding capacity, drainage, aeration and how easily the soil can be cultivated.

Cation exchange capacity

The ability of a soil to hold positively charged nutrient ions on clay and organic matter surfaces; sandy soils have low CEC and therefore low nutrient-holding ability.

Soil erosion control

Practices that reduce soil loss: contour ploughing, terracing, grass strips, mulching, cover crops, shelterbelts and controlled grazing to keep protective vegetation cover.

Crop rotation

Growing different crops in a planned sequence on the same land; rotating cereals with legumes adds nitrogen and breaks pest, weed and disease cycles.

Plant population

The number of plants per unit area, calculated from row and within-row spacing; correct population ensures efficient use of light, water and nutrients.

Seed germination percentage

The proportion of seeds that sprout under suitable conditions; good quality seed for planting should have a germination percentage above about 85 percent.

Drip irrigation

A method that delivers water slowly and directly to the root zone through emitters; it is the most water-efficient irrigation method because evaporation and weed growth are reduced.

Ruminant digestion

A four-chambered stomach (rumen, reticulum, omasum, abomasum) in cattle, sheep and goats that ferments fibrous plant material with the help of microbes.

Tswana cattle breed

An indigenous Botswana breed valued for hardiness, tick tolerance, walking ability and adaptation to extensive grazing; it is the backbone of communal cattle production.

Gestation periods

The length of pregnancy: about 283 days in cattle, 150 days in sheep and goats, and 114 days in pigs; used to plan breeding and expected calving dates.

Livestock traceability

A system of branding, ear-tagging and recording all cattle movements in Botswana, enabling disease control and supporting access to beef export markets.

Primary tillage implements

Implements such as the mouldboard plough and disc plough that cut, invert and pulverise soil to prepare land for planting and to bury weeds and residues.

Mouldboard plough

A primary tillage implement that inverts and breaks up soil, burying weeds and crop residues; it works well on friable soils but less well on hard, stony ground.

Machine field capacity

The theoretical area a machine covers per hour, calculated as working width in metres multiplied by speed in km/h, divided by ten.

Knapsack sprayer calibration

Measuring nozzle output and spray volume so the correct dose of pesticide or fertiliser is applied per hectare, adjusted by nozzle size, pressure or walking speed.

Grain storage conditions

Grain must be dried to about 12-13 percent moisture and stored cool, dry and clean; higher moisture encourages mould growth and insect pests such as weevils.

Dipping tank

A structure holding dip wash used to treat cattle against external parasites such as ticks and mites; the wash must be kept at the correct concentration.

Fencing types

Barbed wire for livestock boundaries, mesh for sheep and goats, electric fencing for stock and predator control, and tall game fencing for wildlife.

Integrated pest management

A pest control approach combining cultural, biological, mechanical and chemical methods, applying pesticides only when pest numbers exceed the economic threshold.

Foot-and-mouth disease

A highly contagious viral disease of cloven-hoofed animals causing blisters and lameness; in Botswana it is controlled by vaccination and strict movement restrictions.

Ticks as disease vectors

External parasites that transmit cattle diseases such as heartwater, anaplasmosis and babesiosis; controlled by regular dipping or spraying with approved acaricides.

Drug withdrawal period

The time after giving a veterinary drug during which milk, meat or eggs must not be sold, so that drug residues have cleared from the animal's body.

Gross margin

Gross output or revenue from an enterprise minus its variable costs; it shows the contribution of the enterprise towards fixed costs and profit.

Break-even point

The level of output at which total revenue equals total cost; calculated as fixed costs divided by selling price per unit minus variable cost per unit.

Botswana Meat Commission

The statutory body that operates export abattoirs and markets Botswana beef, enforcing veterinary and quality standards for export to international markets.

Agricultural extension

The process of transferring knowledge, skills and technology from research to farmers through advice, demonstrations, field days, training and mass media.

Cooperative principles

Voluntary and open membership, democratic one-member-one-vote control, member economic participation, autonomy, education and concern for the community.

Overgrazing

Continuous heavy grazing that removes grass cover, causing soil compaction, erosion and bush encroachment, and reducing the long-term grazing capacity of rangeland.

Bush encroachment

The spread of woody shrubs such as Acacia and Dichrostachys into rangeland, reducing grass production; controlled by burning, clearing, arboricides or goat browsing.