Biodiversity is the variety of plant and animal species that inhabit and coexist in a particular area, which are essential for the maintenance of a working ecosystem. Overgrazing is one of the most common causes of loss of biodiversity. Which in turn leads to disruption of the ecosystem. This, however, can be avoided by implementing very simple solutions, which we will explore in this article.
What is Biodiversity?
In literal terms, biodiversity is defined as:
“The variety of flora and fauna in the world or in a particular habitat, a high level of which is usually considered to be important and desirable.”
This means that all the plants and animals are indigenous to a specific region, and without those plants and animals it would be impossible to keep the natural ecosystem of that particular region functioning.
Multiple biodiversities (MBD) include every living being- from humans to microbes and all in between. A complete loss, or significant decline in the number of one or more of these plant or animal species, leads to destabilisation of the ecosystem multifunctionality (EMF), and in some cases a complete loss of the natural habitat, turning a healthy, lush green field into an inhospitable patch of barren earth.
The area of these drylands is expected to expand by 11–23% by the end of this century.
The main reasons for that are:
- Climate change
- Poaching of indigenous animals
- Overexploitation of the natural environment e.g. overgrazing
Why is Biodiversity Important?
Biodiversity is of vital importance for humans because humans and human activities constitute a central role when it comes to dynamic interactions within and among ecosystems.
The benefits of biodiversity include:
- Food production
- Fibre production
- Fodder for grazing animals
All of these have substantial economic benefits.
Although it is true that human activities are the leading cause of the loss of trophic biodiversity, however, it is also true that whenever the terrestrial ecosystem suffers the loss of biodiversity, we suffer the most.
Effect of Overgrazing on Biodiversity:
Overgrazing occurs when plants of a particular habitat are exposed to excessive grazing for extended periods of time.
Generally speaking, overgrazing has been considered one of the key factors affecting biodiversity and land degradation in temperate regions. The effect of grazing on MBD in a particular habitat depends on the following factors:
- Intensity of grazing
- Type of livestock
- Climatic aridity
Farmers should keep an eye out for overgrazing as it can lead to a number of problems, such as:
1. Decrease in Leaf Area:
Repeated overgrazing leads to defoliation and more than 50% loss of flora diversity. This causes a decrease in leaf surface area, the principal intake of solar energy in the ecosystem. This causes plants to pull more nutrients from the soil in order to grow more leaves, leading to a decrease in soil fertility.
2. Damage to the Root System:
Overgrazing causes irreparable damage to the root system. The decreased surface area of leaves is insufficient to carry out photosynthesis to provide adequate energy for the maintenance of the root system. Thus leading to a decline in plant root health over time.
3. Soil Erosion:
Regular overgrazing in pastures leads to weakened topsoil integrity, which in turn leads to soil erosion. It can be either interrill, rill or gully erosion. It causes nutrient depletion in the soil.
4. Soil Compaction:
When grazing sources are limited, farm animals tend to bunch up together while feeding. The hoof pressure of these animals causes compaction in the soil. This reduces water infiltration and drainage, which further decreases soil fertility.
5. Shifted Species Composition:
The composition of species in the pasture will also begin to shift after a mere two years of overgrazing. This will lead to an increase in weed and forb growth.
In the long run, these changes will eventually lead to desertification.
Easy Solutions to Overgrazing:
Overgrazing can have a devastating impact on the environment and the economy. Fortunately, there exist very easy solutions to completely avoid overgrazing and biodiversity loss in the first place.
Following are some important solutions for maintaining healthy grazing activity:
- It is common sense that overgrazing directly correlates with the number of livestock animals. There are several methods of grazing management that can be utilised to avoid overgrazing, such as: rotational, cell, mob or holistic grazing.
- Understanding the plant growth cycle and plant growth rate can help the farmer maintain a healthy, green pasture. By introducing plants with shorter growth cycles and methods such as plant rotation, a lot of issues associated with overgrazing can be avoided.
- Remove livestock from bare soil areas. Many animals love to graze in the same spot every day. This decreases the rate of plant growth from that particular spot. Rotating livestock away from these spots will lead to the restoration of plant growth.
- Land and livestock management, along with agroecological practices, leads to an increase in plant productivity and in turn, better animal health.
- Farmers need to understand that grazing is not the only way to feed livestock. In fact, livestock can be efficiently fed on stored fodder as well. Hay, straw, silage, compressed and pelleted feeds, sprouted grains and legumes, such as bean sprouts are excellent fodder for livestock.
- Before regrowth begins, farmers must move the livestock out of the pasture. They can be moved to a separate paddock.
- On that same note, by building a series of paddocks, sufficient restoration periods can be granted to areas with higher grazing activity. It is recommended to build at least six to eight paddocks, however, the actual number depends on the size of your livestock.
- Farmers should avoid letting livestock graze early. This reduces plant growth and leads to bare soil. Which ultimately causes desertification.
- Additionally, producers can draw up a grazing chart. This will help them plan and implement rotational grazing as well as track the time for which the livestock is kept in different paddocks.
Economic stability cannot be achieved if there is no environmental sustainability. Therefore, it is favourable to avoid overgrazing altogether, rather than dealing with the consequences of biodiversity loss later.
This brings us to the end of the article, until we meet again, Happy Farming!
- The Dedicated Team of Pasture.io, 09 June 2022