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1.
Proc Natl Acad Sci U S A ; 117(49): 31249-31258, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33229550

RESUMO

For species to stay temporally tuned to their environment, they use cues such as the accumulation of degree-days. The relationships between the timing of a phenological event in a population and its environmental cue can be described by a population-level reaction norm. Variation in reaction norms along environmental gradients may either intensify the environmental effects on timing (cogradient variation) or attenuate the effects (countergradient variation). To resolve spatial and seasonal variation in species' response, we use a unique dataset of 91 taxa and 178 phenological events observed across a network of 472 monitoring sites, spread across the nations of the former Soviet Union. We show that compared to local rates of advancement of phenological events with the advancement of temperature-related cues (i.e., variation within site over years), spatial variation in reaction norms tend to accentuate responses in spring (cogradient variation) and attenuate them in autumn (countergradient variation). As a result, among-population variation in the timing of events is greater in spring and less in autumn than if all populations followed the same reaction norm regardless of location. Despite such signs of local adaptation, overall phenotypic plasticity was not sufficient for phenological events to keep exact pace with their cues-the earlier the year, the more did the timing of the phenological event lag behind the timing of the cue. Overall, these patterns suggest that differences in the spatial versus temporal reaction norms will affect species' response to climate change in opposite ways in spring and autumn.


Assuntos
Adaptação Fisiológica/fisiologia , Mudança Climática , Monitoramento Ambiental , População , Animais , Ecossistema , Estações do Ano , Temperatura , U.R.S.S.
3.
Sci Data ; 7(1): 47, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32047153

RESUMO

We present an extensive, large-scale, long-term and multitaxon database on phenological and climatic variation, involving 506,186 observation dates acquired in 471 localities in Russian Federation, Ukraine, Uzbekistan, Belarus and Kyrgyzstan. The data cover the period 1890-2018, with 96% of the data being from 1960 onwards. The database is rich in plants, birds and climatic events, but also includes insects, amphibians, reptiles and fungi. The database includes multiple events per species, such as the onset days of leaf unfolding and leaf fall for plants, and the days for first spring and last autumn occurrences for birds. The data were acquired using standardized methods by permanent staff of national parks and nature reserves (87% of the data) and members of a phenological observation network (13% of the data). The database is valuable for exploring how species respond in their phenology to climate change. Large-scale analyses of spatial variation in phenological response can help to better predict the consequences of species and community responses to climate change.


Assuntos
Biota , Mudança Climática , Bases de Dados Factuais , Quirguistão , República de Belarus , Federação Russa , Estações do Ano , Ucrânia , Uzbequistão
4.
J Comput Chem ; 28(4): 778-82, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17226828

RESUMO

The performance of the newly proposed 6-31G(##) basis set for calculating the equilibrium structure and vibrational frequencies of transition metal carbonyl complexes has been studied at the HF and DFT levels of theory. The 6-31G(##) basis set has been constructed by augmentation of the 6-31G basis set by diffuse and polarization functions, which are generated from the corresponding 6-31G basis AOs response functions obtained in the frame of propagator approach. The predicted values of bond distances and vibrational frequencies for the title compounds are in good agreement with the experimental data. The relative energies and HOMO-LUMO gaps were also estimated for the series of MCO complexes.

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