University of Bologna

About: University of Bologna is a education organization based out in Bologna, Emilia-Romagna, Italy. It is known for research contribution in the topics: Population & Galaxy. The organization has 38387 authors who have published 115176 publications receiving 3460869 citations. The organization is also known as: Università di Bologna & UNIBO.

Stomatal, mesophyll conductance and biochemical limitations to photosynthesis as affected by drought and leaf ontogeny in ash and oak trees

Abstract: Gas exchange measurements were carried out on ash and oak trees in a forest plantation during three whole growing seasons characterized by different water availability (2001, 2002 and 2003). A quantitative limitation analysis was applied to estimate the effects of drought and leaf ontogeny on stomatal ( S L ) and non-stomatal limitations ( NS L ) to light-saturated net photosynthesis ( A max ), relative to the seasonal maximum rates obtained under conditions of optimal soil water content. Furthermore, based on combined gas exchange and chlorophyll fluorescence measurements, NS L was partitioned into a diffusive (due to a decrease in mesophyll conductance, MC L ) and a biochemical component (due to a decrease in carboxylation capacity, B L ). During the wettest year (2002), the seasonal pattern of both A max and stomatal conductance ( g sw ) was characterized in both species by a rapid increase during spring and a slight decline over the summer. However, with a moderate (year 2001) or a severe (year 2003) water stress, the summer decline of A max and g sw was more pronounced and increased with drought intensity (30‐40% in 2001, 60‐75% in 2003). The limitation analysis showed that during the spring and the autumn periods S L , MC L and B L were of similar magnitude. By contrast, from the summer data it emerged that all the limitations increased with drought intensity, but their relative contribution changed. At mild to moderate water stress (corresponding to values of g sw > 100 mmol H 2 O m

The Third Catalog of Active Galactic Nuclei Detected by the Fermi Large Area Telescope

Abstract: The third catalog of active galactic nuclei (AGNs) detected by the Fermi-LAT (3LAC) is presented. It is based on the third Fermi-LAT catalog (3FGL) of sources detected between 100 MeV and 300 GeV w ...

The economic value of cultural diversity: evidence from US cities

Abstract: WhataretheeconomicconsequencestoU.S.nativesofthegrowingdiversity ofAmericancities?Istheirproductivityorutilityaffectedbyculturaldiversity asmeasuredbydiversityofcountriesofbirthofU.S.residents?Wedocument in this paper a very robust correlation: US-born citizens living in metropolitan areas where the share of foreign-born increased between 1970 and 1990, experiencedasignificantincreaseintheirwageandintherentalpriceoftheir housing. Such finding is economically significant and survives omitted variablebiasandendogeneitybias.Aspeopleandfirmsaremobileacrosscitiesin the long run we argue that, in equilibrium, these correlations are consistent with a net positive effect of cultural diversity on the productivity of natives.