Rangelands are grasslands heavily used for the purpose of meeting animal farm requirements. Therefore, it is not surprising that it is these lands that are heavily affected by overgrazing. I’ve written extensively about the role overgrazing plays in land degradation. Let’s now look at what we can do to bring these heavily degraded rangelands back to full health via restoration ecology…
Signs of overgrazing
There are clear indicators in terms of the plant composition, soil condition and livestock heath that tell us if a rangeland is overgrazed and degraded. These factors help us identify the site for restoration.
Plants that are commonly found in degraded rangelands are weeds. Some of the species are Lantana, Berberis, Opuntia sp., Euphorbia sp., Agave sp., Poa pratensis, Bromus sp., Nicotiana sp., etc.
Weeds have the ability to live in heavily degraded soils as well. When you find any of the above mentioned weeds, you are likely to find soils that are heavily leached, compact, very thin layer of top soil and have low nutrient content.
Along with these, the livestock that graze there are likely to display poor health, poor appetite and low reproductive desires (so if you find a lack of humping in your sheds, you know there is a problem!).
What to do now that you know the land is overgrazed?
Here’s when we start our restoration process.
- We obviously find out the ecological history of the identified site, including natural vegetation cover, past grazers before it became an economic rangeland, climactic conditions, soil conditions, rainfall patterns and seasons where the grasses are most potent at spreading.
This information, although important in every restoration project, is particularly important here because rangelands are heavily influenced by rainfall, climate, topography and vegetation composition. Our technique for restoration has to be tweaked depending on these characteristics of the site.
- Next, all the weeds are to be cleared.
- After clearing the area, it should be fenced off so that passing grazers do not wander into the area and disturb the restoration process.
- Meanwhile, we work on soil and water conservation measures. These include landscape contouring, digging trenches and furrows for soil; rainwater harvesting and building artificial ponds/lakes for water.
- Land is then prepared for seeding. The seeds are obviously selected with care. As always, native species of grasses are preferred. These plants need to show all the characteristics that I mentioned in selecting plants for a degraded land restoration project.
- The method of seeding varies depending on our requirements. It can be distributed randomly (called broadcasting) or it can be sown like in an agricultural field (called line sowing). It is important that the seeds are at the right depth; grass seeds are very small and will not germinate when sown too deep. 0.5-2 cm is the ideal depth.
- If required, the nutrient conditions of the area is improved by adding manure and/or fertilizers.
- This area is to be left alone for a few months and monitored closely, to ensure the rangeland is restoring itself to full health.
- Once it does restore itself (grasses grow and mature quite fast. The time periods for rangeland restoration is different from minespoil restoration or wasteland restoration), we can focus on the grazers.
- To prevent future degradation of rangelands, proper grazing management practices need to be employed. This includes rotation of grazers around the entire rangeland, mixed grazing (different grazers eat different parts of the grass), among other methods.This ensures that one area does not get heavily degraded. It allows the vegetation to regrow before it is attacked by grazers again. It also improves productivity of the rangeland, because this improves nutrient cycling.
The final step, as always, is monitoring, long term management and flexibility in case something unforeseen happens.