**5. Effects of animal grazing patterns on arable lands**

FAO [17], indicated that the utilization-animal relationship may be described by developing the model of animal responses and production per hectare, where it can be noticed that the production per hectare rapidly declines at optimum stocking rate. However, under-grazed areas with few animals can produce a greater total production than overgrazing with more animals. Consequently, the retrogression which is referred to as the replacement of community plants of high ecological order with a community of low ecological order can result [18]. In turn, the cattle grazing pattern often changes during the dry season, which results in high mortality rates and high cull rates in smallholder farmers. In South Africa, rangelands are divided into two veld types, which are Sweetveld type and Sourveld types. Sweetveld types are generally characterized by palatable grass species and low rainfall distribution, whereas Sourveld type is characterized by unpalatable grass species with low rainfall distribution.

Invaders are also commonly found in degraded areas. Invaders are defined as the species that were absent or present in a small amount in the original vegetation, which invade the following disturbance of continued grazing overgrazing.

Invader is less productive than increasers and is of little value as regards soil and water conservation. In some instances, animals often refrain from drinking water, giving nothing in return, and livestock refuses to graze some species. Eventually, the animals are forced to graze even unpalatable species or die due to starvation, which more productive animals and leaves those unproductive and demanding animals which manage to survive, resulting in reduced economic returns.

Hoffman et al. [19], reported that keeping animals too long in a paddock results in reduced grass vigor. Not allowing a grassland sufficient time to restore the carbohydrates reserves. Increased grazing capacity results in decreased grassland productivity, decreased biodiversity, and ultimately lead to soil erosion and loss of nutrients [2].

### **6. Forage legumes effects on veld degraded areas**

Most of the forage is available over much of the year to dairy cattle in the tropics is its low quality compared to temperate areas. It can be overemphasized that higher production can be obtained for certain grass species, for example, *Paspalumdilatatum* incorporated with white clover (*Trifoliumrepens*) [20].

However, once pastures are established, without doubt, the most critical aspect of dairy production is maintaining pastures at a level to provide sufficient quality to enable genetically high producing dairy animals to reach their genetic potential.

*Effects of Veld Degradation on Biomass Production in the Arable Lands of South Africa DOI: http://dx.doi.org/10.5772/intechopen.102605*
