Environmental impacts of beef: habitat conversion
Mounting damagesAn area of the world's rainforest larger than New York State is estimated to be destroyed each year to create grazing land. This not only alters the composition or existence of native plant communities but also the species of wildlife that existed in those plant communities.
Plant communities are altered over much of the world, often as a result of direct intervention such as ploughing native grassland vegetation and establishing either single-species or mixed-species pastures of introduced species.
The species composition of natural grasslands is transformed by continuously overstocking native rangeland with livestock, enrichment planting (e.g., sowing seeds of introduced species in native grassland), and eliminating intentional burning.
Pastures - damaging local biodiversity
Pasture can be created from temperate or tropical forests or savannas. This often involves converting native habitat and introducing grass and forage species that provide more food for cattle. In natural grasslands the biggest impact is the alteration of the native plant communities and the associated impacts on wildlife and other biodiversity.
In addition, cattle are increasingly fed hay and grains to supply food during the dry or winter seasons, or to fatten them before slaughter. While forests have been cleared to make way for livestock throughout the world, the most significant impacts recently have been in the Amazon, where massive clearing of tropical forests has had a tremendous impact on biodiversity, ecosystem functions, and even local climate.
Maintaining desired pasture composition in created pastures often requires tillage, chemical fertilisers, and pesticides. Continuous grazing causes plants to produce more leaf biomass and less root biomass. This reduces their ability to survive during periods of stress (e.g., extended cold, hot, or dry spells).
Watershed protection also suffers as plant cover and leaf litter diminish, leaving the soil exposed and erodible. In areas where pastures are not maintained, woody plants tend to dominate over time, not only affecting ecological balance but also reducing the carrying capacity for cattle.
Irreversible damages to degraded agricultural land
Another source of pasture is degraded agricultural land. In many areas, once land can no longer produce agricultural crops, it is used for livestock. Such land is already degraded. However, converting it to pasture degrades it even further, virtually ensuring that it will not return to anything near its natural state.
Displacing the rural poorCattle production can cause habitat conversion indirectly as well. In some instances cattle are a "push" factor, displacing the rural poor into fragile areas.
In Central America, for example, the conversion of labour-intensive, cash crop-producing areas to cattle production caused many landless poor to move into and clear tropical forest areas for subsistence production.
In a variation on this pattern, the rural poor and landless in the Amazon often clear land, grow a crop or two and then plant the land to pasture to sell to ranchers.