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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.
Rev. biol. trop ; 67(3)jun. 2019.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1507531

RESUMO

Testate amoebae diversity from 28 surface (0-3 cm depth) soil samples found near Cuzco (6 samples), in Machu Piсchu (17 samples), in Aguas Calientes (5 samples), and one bottom sediment sample from the Lake Titicaca near the Puno collected during March of 2016 were analyzed. The 144 testate amoebae species and infra-specific taxa belonging to 27 genera were identified. Nineteen amoebae have not been identified to species level and likely represent new taxa. Species richness varied from one to 54 taxa per sample. The highest diversity was found in rainforests followed by those in meadows and agave habitats. The only bottom sample from Lake Titicaca has yielded two hydrobiont species from the genus Difflugia. In the course of the study, several rare species with limited geographical distribution were observed, namely Centropyxis castaneus, C. compressa, C. deflandriana, C. latideflandriana, C. cf. ohridensis, C. cf. ovoides, C. cf. pannosus, C. stenodeflandriana, Cyclopyxis plana, C. profundistoma, Apodera vas, Argynnia retorta, A. spicata, Certesella certesi, Trachelcorythion pulchellum. Our study fills a geographical gap in the distribution of some flagship species with restricted geographic distribution, e.g. Apodera vas and Certesella certesi in Peru. The results illustrate the continuity of expansion species along the Pacific coast.


La diversidad de amebas testadas de la capa superior del suelo (0-3 cm de profundidad) fue analizada en 28 de muestras recolectadas cerca de Сuzco (seis muestras), Machu Picchu (17 muestras) y Aguas Calientes (cinco muestras), así como una muestra de sedimentos del fondo recolectada en el lago Titicaca, cerca de la ciudad de Puno, en marzo 2016. Se identificaron 144 especies de amebas testadas y taxones infra-específicos pertenecientes a 27 géneros. Un total de 19 amebas no han sido identificadas a nivel de especie y probablemente sean nuevos taxones. La riqueza de especies varía de uno a 54 taxones por muestra. La mayor diversidad fue encontrada en los bosques pluviales, prados y hábitats de agave. En los sedimentos del fondo del lago Titicaca se encontraron 2 especies hidrobiónticas del género Difflugia. En el estudio se encontraron varias especies raras con una limitada distribución geográfica, tales como: Centropyxis castaneus, C. compressa, C. deflandriana, C. latideflandriana, C. cf. ohridensis, C. cf. ovoides, C. cf. pannosus, C. stenodeflandriana, Cyclopyxis plana, C. profundistoma, Apodera vas, Argynnia retorta, A. spicata, Certesella certesi y Trachelcorythion pulchellum. Nuestro estudio llena un vacío en la distribución geográfica de algunas especies importantes de Perú, que tienen una distribución geográfica limitada, por ejemplo: Apodera vas y Certesella certesi. Los resultados muestran la continuidad de la expansión de las especies a lo largo de la costa del Pacífico.

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