How to reverse soil degradation on your farm

Worldwide, primary livestock production has seen both a decline in output and a rise in input costs. At the same time, the entire agriculture sector has found itself under the spotlight for causing major environmental degradation.

“This could be blamed on more carbon dioxide [CO2] and water vapour being released into the atmosphere, the first from degrading soil and the second due to increased evaporation from bare soil,” says Colin Nott, a regenerative agricultural consultant from Namibia.

According to Nott, arid regions account for approximately 40%, or 5,2 billion hectares, of Earth’s land surface. A considerable portion of these are suited to livestock and, to a lesser extent, crop production.

Most of the world’s arid zones are also expanding into more humid areas through desertification. This is the process by which fertile land becomes less productive, typically as a result of inappropriate land management, and the problem is made worse by deforestation.

Degradation in Namibia
In Namibia, 60 million hectares are suitable for livestock production, but virtually all of this land has been degraded to some extent, according to Nott. Perennial grasses, herbs and soil cover have been destroyed in many places, while plant biodiversity and overall production has declined markedly. Of these 60 million hectares, 45 million are now severely bush-encroached.

In many parts of the country, sustainable stocking rates (SSRs) are 50% lower than those of between 50 and 100 years ago. Put more bluntly, the land can now support only half of the animals it did then.

The SSR is the most important profit driver in a livestock enterprise, says Nott. This figure, combined with animal performance, determines how many kilograms/ha of meat a farmer can produce sustainably over time.

A declining SSR means declining productivity and ultimately dwindling profitability. If the current downward spiral is not turned around, many producers are bound to go out of business at some point.

“This is the crux of the matter in Southern Africa,” says Nott.

“Livestock producers are not only struggling in Namibia. Botswana, South Africa, Zimbabwe and other dry climates of the world display similar levels of degradation and face the same issues.”

In contrast, by keeping track of the daily performance of every animal and implementing rangeland management plans that provide for an increased SSR, farmers can increase their profits.

There are fundamental differences between managing rangelands in arid areas and doing so in areas with predictable rainfall or precipitation distributed evenly all year round. Arid regions are subject to highly inconsistent rainfall in terms of volume and distribution. As a result, the timing of plant growth and the amount of forage produced in a growth season are unpredictable.

In these areas, it has become imperative to introduce rangeland management practices that increase forage production and slowly raise the SSR of livestock farms. These practices ensure that carbon is added to the soil to boost soil organisms, that nutrients are made available to plants, and that the soil structure is rebuilt over time.

Plants and microbes
Nott points out that Earth is effectively a planet of plants and microbes, with the former making up about 80% and the latter 18% of living carbon. All other life forms (humans, livestock, game, fish, insects, and so on) make up the remaining 2%.

Plants and microbes depend on one another, and livestock farmers need to understand the dynamics of this relationship. Successful rangeland management primarily involves encouraging the beneficial relationship between plants and microbes.

Plants produce sugars using CO2 and sunlight, and through photosynthesis these are made available in the soil to feed microbes. The microbes, in turn, use this energy to multiply
and take in minerals from the surrounding soil.

They also rebuild soil structure, increasing the soil’s moisture-holding capacity, which stimulates the growth of both plants and microbes. When the latter die, the energy, minerals and nutrients that they created are taken up by the plants’ roots.

These processes increase biodiversity to the benefit of forage production and quality.

“Improving the soil microbiome encourages perennial grass, palatable herbs, shrubs and other plants to germinate,” says Nott.

In this way, the growing season is extended and palatable plants return. The SSR is increased as more forage is produced, and input costs decline because of the increased quality and nutritional value of the forage.

“Current management systems are based largely on selective grazing, with inadequate recovery periods, a process that leads to bare patches of ground, a reduction in photosynthesis, and shortened photosynthesis periods. This limits the number of soil microbes and results in major soil carbon loss, a collapse in soil structure, and increased water run-off. Bare, dead soil in turn impairs production and pushes up input costs,” explains Nott.

Adequate recovery of forage plants between grazing events ensures that plants are not reutilised before they have recovered. Over-rest (not utilising a perennial grass plant for many seasons), on the other hand, leads to degradation and can occur in the same camp at the same time.

Regeneration techniques
A number of regenerative rangeland approaches for extensive conditions have been identified and included in the National Namibian Regenerative Livestock Strategy.

All these methods involve the establishment of a grazing plan for the growing and non-growing season, and all adjust their stocking rate annually in relation to the amount of forage produced on the farm.

The split-ranch approach (also called the Riaan Dames approach)
In this method, the camps on the farm are divided in two. One set is grazed during
this year’s growing season, while the other is rested. The camps are swapped in the following season. This approach provides for moderate animal density and an entire growing season’s recovery period. It calls for medium management inputs and is particularly suitable for the part-time farmer.

The Mara approach
This is similar to the split-ranch approach, but allows for two full growing seasons’ recovery before camps are grazed again. Animal density in this approach is relatively low, selection is good, and animal performance is very good. The method also requires medium management inputs.

Holistic management
Several fundamentally different holistic management approaches are included in the regenerative livestock strategy. All of these approaches involve combining herds and implementing a grazing plan. Most farmers will have to invest in water delivery and storage before implementing it. The animals in a grazing group are contained with fixed and/or mobile electric fences or through herding.

The Ian Mitchell-Innes approach
Here, herds are combined, which results in high animal density or many animals in a
camp at the same time. The approach allows these large herds to be kept in a camp for
only a very limited period. It keeps the favourable grass in the vegetative state, which stimulates it and ensures good animal performance. The recovery period of plants can be as short as 25 days, as most of the plants remain intact after the grazing event.

Traditional holistic management approach
This approach also combines herds and therefore applies high animal density. As a greater percentage of the grass plant is used, selection is reduced and a long recovery period (up 120 days) is required. Livestock performance must be monitored closely and mitigating action taken to avoid animal performance losses. The animals may be moved daily or every second day.

Ultra-high-density grazing
This method usually employs strip grazing with the aid of mobile electric fences, and concentrates the combined herd on the ‘new grass’ made available to animals as the fence is moved (possibly hourly). It limits the ability of animals to select, and long recovery periods are required (140 days or more). In most instances, animal performance should be enhanced with a rumen supplement. Alternatively, highly adapted animals can be used and carefully selected on an ongoing basis.

Planned grazing and combined herding
This highly effective approach is normally used where fencing is not allowed (for example, in the communal areas of Namibia) or too expensive. The animals are combined into one herd, herded daily according to a grazing plan, and kraaled nightly. The kraals can be moved weekly, resulting in impressive regeneration on these sites.

This method can also be used to treat gullies and it has been used effectively in Namibia to create synergies between wildlife (including lions and elephants) and livestock, whilst regenerating the land for all species. It requires no fencing, or limited fencing infrastructure if done on an already fenced farm.

Seek advice!
To avoid mistakes that have been made before, producers are strongly advised to obtain professional guidance on selecting a regeneration approach. In general, the higher the density of grazing, the faster the regeneration (that is, the more grass will grow). At the same time, though, the need to mitigate the risks will be more urgent and the management and financial inputs will be greater.

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