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RIMAIAgribusiness SchoolMy land

Module 9 Core Course

Climate, Water and Resource Risk

What can drought, water shortage and land degradation do to my business, and how do I build the venture to survive them?

A farm veranda office under mopane trees where the owner works through the numbers

Aligned to the UN Sustainable Development Goals

6Clean water13Climate action15Life on land

Aligned to ISO standards

ISO 14001Environmental managementISO 14046Water footprint
How RIMAI is aligned

Southern Africa is dry and getting more variable. Rainfall, water allocations and the condition of grazing land are the resources most likely to break a farm business, and the region’s commercial farmers plan around them as carefully as they plan around prices. This module teaches the student to treat climate and water as business risks with a cost attached.

Dryland farming compared with irrigated farming and the enterprises each supportsWater decides the enterpriseDryland: rain onlyIrrigated: borehole, dam or riverboreholeDrought-tolerant crops, grazing, sorghumHigh-value vegetables, fruit, seed crops

Lesson 9.1 - The rain-fed bet

Article 20 explains that South African maize is overwhelmingly dryland, with under a tenth of the crop irrigated. Every season is a bet on the rain. In a good year it pays handsomely; in a drought year the whole sector moves, and the region watches its own future in the swing. Article 137 adds that the most expensive assumption in African agriculture is that next season’s rain will fall where last season’s did.

For the student, rain-fed production means accepting that some years will fail and planning the finances to survive them: a cash reserve, crop insurance where it exists, a drought-tolerant crop in the mix, and costs kept low enough that one bad year does not end the business. Zimbabwe’s decision to pay the same GMB price for traditional grains as for maize is designed to encourage drought-tolerant small grains for exactly this reason.

Lesson 9.2 - Water is the binding constraint

Article 138 states the region’s central truth: Africa has abundant arable land but frequently lacks the water to farm it reliably. In South Africa the binding constraint on growth is not hectares but litres. Article 33 shows how export orchards draw on contested rivers whose allocations are tightening.

Before any irrigated venture, the student establishes the water source - borehole, river, dam or municipal supply - its legal right of use, its reliable volume in the driest month, and the cost of pumping it. An irrigated plan that has not tested its water in the dry season is not a plan. The water budget sets the maximum irrigated area, and that area, not the land size, sets the scale of the business.

Lesson 9.3 - Controlled-environment farming

Article 52 describes hydroponics and greenhouse production as the response to water scarcity: every litre measured, yields per square metre far above open fields, and production that can run year-round. The trade-off is capital. Tunnels, greenhouses, irrigation systems and climate control cost money up front and need skilled management. Controlled-environment farming suits high-value crops sold to reliable buyers close to the farm, where the higher yield and steady supply pay back the investment.

Lesson 9.4 - Rangeland: the slow write-down

Article 72 describes rangeland degradation as a balance-sheet write-down nobody books. South Africa relies on extensive grazing across roughly 80% of its agricultural land. Overgrazed veld looks the same from year to year while its capacity to carry animals falls. Article 73 adds that livestock now carries a methane cost on the carbon ledger that may shape future market access.

The working tool is carrying capacity - how many animals a given area of land can support without degrading it. A livestock plan starts from the carrying capacity of the land, not from the number of animals the owner would like. Stocking above it borrows from the land’s future.

Lesson 9.5 - The destocking spiral

Article 74 explains how drought does its damage twice: first it kills the grass, then it crashes the market as every farmer sells at once. Prices fall exactly when farmers must sell, and rebuilding the herd takes years. The defence is to sell early, before the forced-sale rush; to hold fodder reserves; and to keep stocking below carrying capacity in normal years so there is a buffer for dry ones.

Lesson 9.6 - Conservation agriculture

Article 139 describes conservation agriculture - minimum tillage, permanent soil cover and crop rotation - as the region’s cheapest climate-adaptation tool. It keeps moisture in the soil, rebuilds organic matter and cuts fuel and labour costs over time. On a small farm it is often the first and cheapest step toward resilience.

The South African benchmark and your market

Market Main climate and resource exposure Reference from the data layer
South Africa Dryland maize, water-limited irrigation, extensive grazing on about 80% of farmland Benchmark
Zimbabwe Rain-fed grain, drought-tolerant small grains supported by price Sorghum: 323,002 t from 528,076 ha in 2025/26
Zambia Rain-fed maize; rainfall for 2026/27 forecast possibly below average Maize harvest projected at 4.9 million t (2025/26)
Botswana Arid and semi-arid; livestock-dominated; recurrent drought National white maize demand far exceeds local output
Namibia Arid; irrigated grapes on the Orange River; extensive grazing Table grapes depend on Orange River irrigation

Apply it to your land

Complete the venture’s resource risk entries in T-C-07 Risk Register. Record the water source, its legal basis and its dry-season volume; the rainfall pattern and what a drought year would do to output; the carrying capacity of any grazing; and the measures the venture will take - insurance, reserve, drought-tolerant crops, fodder, conservation practices. Put a cost on each measure and include it in the budget.

Dictionary terms introduced

Code Term Plain meaning
D-dryland Dryland farming Crop production that relies on rainfall without irrigation
D-water-right Water right The legal permission to take and use a given amount of water
D-controlled-environment Controlled-environment farming Growing crops in tunnels or greenhouses where water, temperature and light are managed
D-carrying-capacity Carrying capacity The number of animals a piece of land can support without being degraded
D-destocking Destocking Selling or removing animals to reduce grazing pressure, often during drought
D-conservation-agriculture Conservation agriculture Farming with minimum tillage, permanent soil cover and crop rotation
D-drought-tolerant-crop Drought-tolerant crop A crop such as sorghum or millet that yields under low rainfall

Calculators: T-C-07 Risk Register.

Library sources: LIB-A020, LIB-A033, LIB-A052, LIB-A072, LIB-A073, LIB-A074, LIB-A137, LIB-A138, LIB-A139.