**5. Conclusions**

Multi-functionality approach recognizes that grasslands have to be considered not only as a means for providing animal products for increasing human population. Also, other additional ecosystem functions as enhancement of carbon sequestration or mitigation of greenhouse gas emissions should be considered by farmers as a way of capitalizing new opportunities to diversify the forage-livestock system (Lemaire, 2007, Sanderson et al., 2007). However returning to the first page of this chapter we remember that degradation processes in tropical grassland are advancing over wide areas through overgrazing on poor soils. So it seems that recuperation and multi-functionality concepts in pasture ecosystems will transit a long way together. We state the central role that the leaf canopy structure, expressed as leaf area index, plays in terms of intercepting solar radiation. Despite this, there are very few studies comparing different alternatives of estimating LAI in forage plants, particularly those of tropical climate. There are several possibilities to apply technologies already available in the generation of new methods. Some of these include: *i*) use of remotely sensed data for monitoring canopy parameters (vegetation indices as NDVI, SAVI and others), *ii*) measurements of foliage cover through digital color photographs taken vertically above the plant canopy using a stationary camera stand (Rotz et al., 2008), iii) a more intensive and creative use of the gap fraction methods including examination of hemispherical photographs for estimates of foliage angular distribution and canopy leaf area. Regarding this last information, the orientation of foliage elements (stems and leaves) is an important piece of information for describing light penetration in canopies especially for tussock grasses.

#### **6. Acknowledgments**

The authors acknowledge the National Research Council for Scientific and Technological Development of Brazil (CNPq) and Carlos Chagas Foundation of Rio de Janeiro (FAPERJ) for granting graduate scholarships and providing funds for the research projects that supported this paper.

#### **7. References**


Multi-functionality approach recognizes that grasslands have to be considered not only as a means for providing animal products for increasing human population. Also, other additional ecosystem functions as enhancement of carbon sequestration or mitigation of greenhouse gas emissions should be considered by farmers as a way of capitalizing new opportunities to diversify the forage-livestock system (Lemaire, 2007, Sanderson et al., 2007). However returning to the first page of this chapter we remember that degradation processes in tropical grassland are advancing over wide areas through overgrazing on poor soils. So it seems that recuperation and multi-functionality concepts in pasture ecosystems will transit a long way together. We state the central role that the leaf canopy structure, expressed as leaf area index, plays in terms of intercepting solar radiation. Despite this, there are very few studies comparing different alternatives of estimating LAI in forage plants, particularly those of tropical climate. There are several possibilities to apply technologies already available in the generation of new methods. Some of these include: *i*) use of remotely sensed data for monitoring canopy parameters (vegetation indices as NDVI, SAVI and others), *ii*) measurements of foliage cover through digital color photographs taken vertically above the plant canopy using a stationary camera stand (Rotz et al., 2008), iii) a more intensive and creative use of the gap fraction methods including examination of hemispherical photographs for estimates of foliage angular distribution and canopy leaf area. Regarding this last information, the orientation of foliage elements (stems and leaves) is an important piece of information for describing light penetration in canopies especially for tussock

The authors acknowledge the National Research Council for Scientific and Technological Development of Brazil (CNPq) and Carlos Chagas Foundation of Rio de Janeiro (FAPERJ) for granting graduate scholarships and providing funds for the research projects that

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