Tropical forest canopies and their relationships with climate and disturbance： results from a global dataset of consistent field-based measurements

Background： Canopy structure, defined by leaf area index （LAI）, fractional vegetation cover （FCover） and fraction of absorbed photosynthetically active radiation （fAPAR）, regulates a wide range of forest functions and ecosystem services. Spatially consistent field-measurements of canopy structure are however lacking, particularly for the tropics. Methods： Here, we introduce the Global LAI database： a global dataset of field-based canopy structure measurements spanning tropical forests in four continents （Africa, Asia, Australia and the Americas）. We use these measurements to test for climate dependencies within and across continents, and to test for the potential of anthropogenic disturbance and forest protection to modulate those dependences. Results： Using data collected from 887 tropical forest plots, we show that maximum water deficit, defined across the most arid months of the year, is an important predictor of canopy structure, with all three canopy attributes declining significantly with increasing water deficit. Canopy attributes also increase with minimum temperature, and with the protection of forests according to both active （within protected areas） and passive measures （through topography）. Once protection and continent effects are accounted for, other anthropogenic measures （e.g. human population） do not improve the model. Conclusions： We conclude that canopy structure in the tropics is primarily a consequence of forest adaptation to the maximum water deficits historically experienced within a given region. Climate change, and in particular changes in drought regimes may thus affect forest structure and function, but forest protection may offer some resilience against this effect.

Middle Jurassic vertebrate assemblage of Berezovsk coal mine in western Siberia (Russia)

The Berezovsk coal mine in western Siberia has yielded the most diverse Middle Jurassic limnic and terrestrial vertebrate assemblage of Asia. The vertebrate remains were recovered by screen washing from floodplain deposits on top of a thick coal seam of the Bathonian Itat Formation. A total of 29 vertebrate taxa has been recorded so far,including hybodontiform sharks,acipenseriforms,palaeonisciforms,amiiforms,dipnoans,anurans,caudates,turtles,squamates,choristoderans,crocodyliforms,pterosaurs,dinosaurs,tritylodontids,and a diverse mammaliaform and mammalian assemblage( eleutherodontids,docodontans,? amphilestids,dryolestids,and zatherians). The caudates are among the oldest in the fossil record and the anurans represent the oldest Asian record of this group. Among the mammals,Anthracolestes is the oldest and most basal known member of Dryolestidae and so far the only record from Asia. The vertebrate assemblage from the Berezovsk coal mine is very similar to that from the British Forest Marble Formation( Bathonian) and suggests a limited provincialism in the Middle Jurassic Laurasian landmass.

Investment pays off More competitive thanks to high quality and low production costs

The experience of the Brazilian spinning mill Sergipe of using the new fully automated rotor spinning machine R 66 has been nothing but positive. No wonder, as the R 66 meets the highest quality standards at low production costs.