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The Brazilian savanna, named locally Cerrado, is the second largest Brazilian biome, covering approximately two million km2, especially in the Central Highlands (Ratter et al., 1997). This biome is composed predominantly of tropical savanna vegetation and is considered as one of the world's biodiversity hotspots, a priority area for biodiversity conservation in the world (Myers et al., 2000). The Cerrado region is considered the last agricultural frontier in the world (Borlaug, 2002), which has been converted in the last 50 years especially for agriculture and pasture purposes, where natural and mainly anthropogenic annual burning is a common practice. Currently, around 50% of natural vegetation in the Cerrado region has been converted to pastures and crops (PROBIO-MMA, 2007).This conversion has impacted the biological diversity, the hydrological cycle, the energy balance, the climate and the carbon dynamics at local and regional scales due to habitat fragmentation, invasive alien species, soil erosion, pollution of aquifers, degradation of ecosystems and changes in fire regimes (Klink & Machado, 2005; Aquino & Miranda, 2008). The knowledge of spatial distribution, temporal dynamics and biophysical characteristics of the vegetation types, are important elements to improve the understanding of what is the interaction like between vegetation, precipitation and fire.

A precipitação é um dos principais fatores que determina a dinâmica sazonal da vegetação na região de savanas tropicais, como é o caso do cerrado brasileiro. Neste trabalho foram analisadas as relações da precipitação sazonal, com o comportamento sazonal das classes de uso e cobertura da terra (UCT), principalmente as fisionomias de cerrado do Estado de Tocantins. Foi analisada a dinâmica sazonal do cerrado, incluindo áreas florestadas e não florestadas, a partir da análise de imagens do MODIS/TERRA IV (Índices de Vegetação) de janeiro a dezembro de 2004, bem como dados diários de precipitação de 2004 e uma série de precipitação diária do período de 1969 a 2005. Os resultados da análise de precipitação mostram que a área de estudo apresentou uma alta sazonalidade, com estação seca de maio a setembro. As análises dos IV mostram que a dinâmica sazonal das formações de cerrado é similar àquela das áreas convertidas para outros usos. O padrão sazonal das classes de UCT segue os padrões da precipitação, cujos menores valores foram registrados no mês de agosto de 2004, mês este que apresentou os menores valores dos IV. Diferentemente das demais classes de UCT, a formação florestal não se ajustou ao padrão de precipitação, apresentando valores de IV similares ao longo do ano com leve decréscimo no mês de setembro de 2004. Precipitation is one of the main factors that determine the seasonal dynamics of the vegetation in tropical savanna areas, as the Brazilian cerrado. In this work the relationship of the seasonal precipitation with the seasonal behavior of the land use and land cover (LULC) types, mainly savannah physiognomies of the Tocantins State, was investigated. We analyzed the savanna seasonal dynamics, including forest and converted areas, with MODIS/TERRA VI (vegetation indexes) satellite measurements from January to December 2004 and daily precipitation of 2004 and daily precipitation series from 1969 to 2005. The results of the precipitation analysis show that the study areas exhibited a high seasonality with a dry season from May to September. The analysis of the VI showed that the seasonal dynamic of the savanna formations and the converted areas were similar. The seasonal pattern of these LULC types follows the precipitation pattern, when the lowest VI values were recorded in August of 2004. Differently of these LULC types, forest formations do not fitted to the precipitation pattern, this LULC type keep similar VI values along year with light decrease in September of 2004.

This chapter presents grassland species diversity to different rangeland conditions and the main environmental and socioeconomic factors. It discusses in Palccoyo, in the high-elevation grasslands of the Andes, puna, Southeastern Peru, looking at the impact of grazing intensity on range conditions and plant diversity in the upper-Andean grasslands. In the high-elevation grasslands of the Andes, known as the puna, extensive grazing land areas have been utilized by rural farmers for over 10,000 years. The puna has a distinct vegetation type that is found predominantly in Andean Peru, but extends into adjacent areas such as Bolivia, north of Chile, and northwestern Argentina. To assist in determining the range condition class for a range site, plant species are grouped as decreasers, increasers, based primarily on the response to grazing intensity. The bofedales range sites showed a greater number of graminoid species than semiarid range sites, whereas semiarid range sites showed a greater number of Gramineae species than bofedales range sites.

The climate in the Caatinga, especially precipitation, influences the pattern of spatial and temporal distribution of the vegetation that in turn influences the regional climate from the feedback mechanism of energy flows, water and momentum. This climate-vegetation interaction in the Caatinga is different depending upon the specific climatic pattern considered. The objective of this work is to identify the main phenological and seasonal features of the annual vegetation growth cycles and of the annual rainy season, respectively, in five climatic regions of the Caatinga biome. We use time series (2001-2008) of vegetation indices such as NDVI and LSWI, and precipitation that was derived of TRMM satellite data and surface station data. The results indicate that precipitation variability in the rainy season influences directly the variability of vegetation growth cycles. This influence is not linear but adjusted to a logarithmic function being better fitted with LSWI (r2 = 0.67) than with NDVI (r2 = 0.54). The influence of precipitation on vegetation, using phenological metrics such as start, end, peak and amplitude of the vegetation growing cycles, showed greater lag in climatic regions with higher precipitation in the Caatinga region

In the Andean transition area the Manu Biosphere Reserve (MBR), in Peru, located within the Amazon basin, there are natural grasslands which are suffering from human impact, due to heavy grazing activities, jeopardising their Carrying Capacity (CC). To minimise this impact, it was found necessary to understand the participation of the environmental variables and the anthropogenic activities generating zone of homogeneous areas so as to ultimately form a management plan. To achieve this goal, those variables were combined, taking into account their spatial arrangement, using geoprocessing techniques. Remote Sensing images were used to produce the land use thematic map and topographic maps were also used to produce a Digital Elevation Model (DEM). Biotic and abiotic parameters were transformed into maps within a Geographical Information Systems (GIS) environment to produce an ecological zoning map. The zoning classes were related to CC and sustainability of the grasslands, and were expressed in maps with 23 sampling units.