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Beef Cattle Production in a Silvopastoral System Beef Cattle Production in a Silvopastoral System in Brazilian Cerrado and its Environmental in Brazilian Cerrado and its Environmental
ImplicationsImplications
Rasmo GarciaUniversidade Federal de Viçosa - UFV
Viçosa, MG, Brazil<[email protected]>
Universidade Federal de ViçosaDepartamento de Zootecnia
CERRADO - the largest savanna region in South America and biologically the richest savanna in all the world
Introduction
• Comprises 1,916,900 square kilometers (740,100 sq miles)
• Brazilian Cerrado has more than 55% of his area disturbed (880,000 square kilometers)
204 million ha
Typical Cerrado vegetation
Introduction
• Degraded soils in Brazilian Cerrado:
Continuous inadequate use of Cerrado vegetation with massive cutting and fire
Continuous agricultural crops
Continuous poor pastures management
High demand for charcoal produced by Cerrado vegetation and eucalyptus forest
Integration of crops, pasture and trees consist in one of the best practices to
recuperate a degraded soil
Silvopastoral systems are in evidence in Brazil
Soil and Climate in Brazilian Cerrado
• Red-Yellow Latosol
• Red Latosol
• Medium texture to clayey
• Very low Ca, P, Mg
• Low K ; pH 4.5 – 5.0
• Precipitation: average 1,350 mm; Dry season: May – October
Introduction
Soybean in Cerrado area Degraded land of soybean cultivation
Introduction
Brachiaria pasture in Cerrado
49.0 million hectare of cultivated pastures supporting a herd of 40.0 million heads,
representing more than 35% of total Brazilian beef production
Pasture land in very poor condition
70% of the cultivated pasture area in fair or poor
condition
Introduction
Forest Plantation in Cerrado 1,500,000 hectares
Eucalyptus is the most common tree
Introduction
• Cultivate one or two annual crops
• On the lanes between the trees rows
• This process can reduce the establishing cost of the whole system
• Farmers are motivated to do by the expectation of the additional income
Establishing a silvopastoral system
b) second year - soybean planted in the lane where rice was harvested.
Beef Cattle Production in a Silvopastoral System
a) first year - rice planted after establishing of eucalyptus
Silvopastoral system: understory (Brachiaria brizantha) showing a green
color even in the dry season Beef cattle in a silvopastoral system
Beef Cattle Production
Bernardino et al. (2008) studied the effects of N and K fertilization on DM production of Brachiaria brizantha and the performance of beef cattle in a silvopastoral system with eucalyptus
• Nitrogen (75 kg ha-1) combined with K (100 kg ha-1) increased (P<.01)DM of the understory resulting in 170 kg (374 lb) of LWG per hectare.
• Nitrogen fertilization (75 kg ha-1) increased (P<.01) LWG an-1 day-1 to .480 kg (1.056 lb).
Garcia et al. (2008) studied three doses of N and two forage offers, 10% and 15%, of a pasture (Brachiaria) in a silvopastoral system with eucalyptus
Research Results
• 165 kg (366 lb) of LWG ha-1 year-1 • 2,100 kg (4,620 lb) of rice ha-1 • 1,800 kg (3,960 lb) of soybean ha-1
Magalhães et al. (2007) in an agrosilvopastoral system found:
IRR – 19%
Research Results
Conclusions: Fertilization and stocking rate adjustments should be considered and more researches will be necessary to establish and manage the silvopastoral system.
Comparison: LWG in a Pasture of Brachiaria Under full sun light - .550 kg an-1 day-1
Silvopastoral system - .480 kg an-1 day-1
Introduction of Forage Legumes as an Alternative to the use of Inorganic Fertilizers
a) Calopogonium mucunoides
Research Results
Silvopastoral system with tropical forage legumes
c) Stylosanthes spp., in cerrado region of Mato Grosso do Sul
b) Stylosanthes spp., in cerrado region of Minas Gerais
• Dissemination of exotic forage grasses, “brachiaria” is prejudicial to biodiversity.
Environmental Implications The main challenges in the preservation of Cerrado
Developing versus Conservation
• Extensive area of native vegetation has been substituted by annual crops, cultivated pastures and reforestation.
• Dissemination of direct planting for annual crops in Cerrado brought enormous contribution to soil conservation.
deficient soil management can result in high soil erosion 20 ton ha-1 year-1 in soybean culture contamination of water resources practicing direct planting the erosion is reduced to 3.0 ton ha-1 year-1.
• Heavy use of limestone and fertilizers contribute to pollute creeks and rivers.
• Monoculture, annual crops or forest plantation, represents a risk to biodiversity and soil conservation
Mosaic of eucalyptus plantations and native Cerrado vegetation as an ecological corridor
(Valverde, 2006)
Environmental Implications
cause great effect in reducing bird populations generally eucalyptus tree need a severe control of ants
Environmental Implications
protect the soil from wind erosion add organic matter to improve soil properties control water erosion by the reduction of rain impact on soil increase water infiltration
• Abusive use of herbicides
contamination of lakes and rivers
• Eucalyptus plantations at high densities
affects insect population tree-forage combinations and spacial arrangements provide greater diversity
and complexity than monoculture systems
• Ants control
• Presence of understory
Silvopastoral systems offer several environmental benefits:
• Potential of carbon sequestration
Final Considerations
• Soil erosion control
• Reduce the use of herbicides and insecticides that have high effect on water quality and biodiversity
• Reduction of native forest cuttings and potential for regenerate degraded pastures
• Minimization of adverse effects of climate
• Improve soil fertility
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