Powered by Blogger.

Thursday, December 3, 2009

Overgrazing and its impact

No comments :

Overgrazing can be defined as grazing plants before they have recovered from a previous grazing. When a plant is grazed severely, it uses energy stored in its roots to support regrowth.As this energy is used, the roots die back. The dying of roots depends on the severity of grazing. This root dieback is not a bad thing. It adds organic matter to the soil, which increases soil porosity, the infiltration rate of water and the soil's moisture-holding capacity. After enough leaves have regrown, the roots will regrow as well.A plant is overgrazed when it's re-grazed before the roots recover. Overgrazing can reduce root growth by 90%. Because there's less root growth, pastures are less productive.

A plant is overgrazed when it's re-grazed before the roots recover. Overgrazing can reduce root growth by 90%. Because there's less root growth, pastures are less productive. Some of very dangerous impacts of overgrazing are listed below -

1. Soils have less organic matter and become less fertile.
2. Porosity of soils decreases.
3. The infiltration rate and moisture-holding capacity drop.
4. Desirable plants become stressed, while weedier species thrive in these harsher conditions. Weeds don't make the land unhealthy. They appear because the land is unhealthy. Overgrazing is often the cause of this adverse and undesirable condition.
5. Animals graze selectively. Given a chance, they will overgraze. The newest growth is the most palatable, nutritious forage in the pasture. Even one cow in a big pasture will overgraze plants if she's kept there long enough.
6. Overgrazing isn't a function of animal numbers. It's a function of time. Overgrazing happens when animals are kept in a paddock too long or brought back too soon.
7. As overgrazing destroys the vegetation completely the entire area becomes prone to desertification and heavy soil erosion that may cause siltation of any river leading to severe floods that may claim large number of lives and great property.





In view of above mentioned serious impacts of overgrazing, some strong measures for checking it must be taken up. These may be -

1. To stop overgrazing, producers must move livestock out of a pasture before regrowth of plants begins again. During the periods of fast growth, overgrazing will occur if livestock are kept in a paddock for more than three or four days.
2. Hearders need to make sure that they don't bring the animals back before plants have recovered.
3. Overgrazing can be stopped with 8-10 paddocks. When growth of plants is fast, recovery periods of four to six weeks may be adequate.
4. Economic sustainability can't be achieved without environmental sustainability. The first step to achieving environmental sustainability is to stop overgrazing. That's essential when one is ranching for profit.
5.Overgrazing by cattle indicates towards irresponsible attitudes of cattle owners. Hence, awareness or some short of legislation to stop overgrazing is urgent for protecting the land against this incidence.

No comments :

Post a Comment

Note: Only a member of this blog may post a comment.