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Abstract: The global savanna biome is characterized by enormous diversity in the physiognomy and spatial structure of the vegetation. The foliage clumping index can be calculated from bidirectional reflectance distribution function (BRDF) data. It measures the response of the darkspot reflectance to increased shadow associated with clumped vegetation and is related to leaf area index. Clumping index theoretically declines with increasing woody cover until the tree canopy begins to become uniform. In this study, clumping index is calculated for Moderate Resolution Imaging Spectroradiometer BRDF data for the Australian tropical savanna, the tropical savannas of South America, and the tropical savannas of east, west and southern Africa and compared with site-based measurements of tree canopy cover, and with area-based classifications of land cover. There were differences in sensitivity of clumping index between red and near-infrared reflectance channels, and between savanna systems with markedly different woody vegetation physiognomy. Clumping index was broadly related to foliage cover from historical site data in Australia and in West Africa and Kenya, but not in Southern Africa nor with detailed site-based demographic data in the cerrado of Brazil. However, clumping index decreased with proportion of woody cover in land cover datasets for east Africa, Australia and the Colombian Llanos. There was overlap in the range of clumping index values for forest, cerrado and campo land covers in Brazil. Clumping index was generally negatively correlated with percentage tree cover from the MODIS Vegetation Continuous Fields product, but regional differences in the relationship were evident. There were large differences in the frequency distributions of clumping index from savanna, woody savanna and grassland land cover classes between global ecoregions. The clumping index shows differing sensitivity to savanna woody cover for red and NIR reflectance, and requires regional calibration for application as a universal indicator. [Copyright &y& Elsevier]

Pasture-based livestock production is largely centered on monoculture systems that degrade grasslands. In integrated crop-livestock-forestry systems a synergy is supposed to occur between its components, contributing to global food production. Thus, this study aimed to evaluate the effects of the microclimate on integrated crop-livestock-forestry (CLF) and crop-livestock (CL) systems on the behavior and body surface temperatures of beef cattle in a tropical climate. The experiment was carried from December/2016 to June/2017. Adult beef cows were maintained in CL (n = 11) or CLF (n = 12) systems, permanently monitored by automatic weather stations. The microclimatic conditions indicated that CLF was more effective in mitigating the environmental heat load. Animals maintained in CLF showed favorable behavior, longer rumination (42.9 ± 2.2 vs 36.6 ± 2.2 min) and shorter resting time (57.6 ± 2.7 vs 65.9 ± 2.8 min) during the morning. The grazing time and other activities did not differ between treatments (P > 0.05) in the afternoon. Animals in CLF exhibited lower surface temperatures of the back (TBack: 31.9 ± 0.2 vs 32.8 ± 0.2 °C, P < 0.05) and of the trunk (TTrunk: 32.0 ± 0.1 vs 32.5 ± 0.1 °C, P < 0.05) measured by infrared thermography. Animals maintained in CLF showed a significant preferential use of shade and a 23% reduction in the frequency of the animals searching for water troughs. It is evident from the study that integrated crop-livestock-forestry systems can be used to provide a more favorable microclimate within grasslands. Thus, beef cattle benefits from the milder environment and exhibits a higher thermal comfort, which favors food production and the rational use of natural resources., (Copyright © 2019 Elsevier B.V. All rights reserved.)