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981.
982.
Vincenzo Penteriani Anna Kuparinen Maria del Mar Delgado Francisco Palomares José Vicente López-Bao José María Fedriani Javier Calzada Sacramento Moreno Rafael Villafuerte Letizia Campioni Rui Lourenço 《Oecologia》2013,173(3):753-766
We compared movement patterns and rhythms of activity of a top predator, the Iberian lynx Lynx pardinus, a mesopredator, the red fox Vulpes vulpes, and their shared principal prey, the rabbit Oryctolagus cuniculus, in relation to moon phases. Because the three species are mostly nocturnal and crepuscular, we hypothesized that the shared prey would reduce its activity at most risky moon phases (i.e. during the brightest nights), but that fox, an intraguild prey of lynx, would avoid lynx activity peaks at the same time. Rabbits generally moved further from their core areas on darkest nights (i.e. new moon), using direct movements which minimize predation risk. Though rabbits responded to the increased predation risk by reducing their activity during the full moon, this response may require several days, and the moon effect we observed on the rabbits had, therefore, a temporal gap. Lynx activity patterns may be at least partially mirroring rabbit activity: around new moons, when rabbits moved furthest and were more active, lynxes reduced their travelling distances and their movements were concentrated in the core areas of their home ranges, which generally correspond to areas of high density of rabbits. Red foxes were more active during the darkest nights, when both the conditions for rabbit hunting were the best and lynxes moved less. On the one hand, foxes increased their activity when rabbits were further from their core areas and moved with more discrete displacements; on the other hand, fox activity in relation to the moon seemed to reduce dangerous encounters with its intraguild predator. 相似文献
983.
Asier Herrero Jorge Castro Regino Zamora Antonio Delgado-Huertas José I. Querejeta 《Oecologia》2013,173(4):1613-1624
Drought-induced events of massive tree mortality appear to be increasing worldwide. Species-specific vulnerability to drought mortality may alter patterns of species diversity and affect future forest composition. We have explored the consequences of the extreme drought of 2005, which caused high sapling mortality (approx. 50 %) among 10-year-old saplings of two coexisting pine species in the Mediterranean mountains of Sierra Nevada (Spain): boreo-alpine Pinus sylvestris and Mediterranean P. nigra. Sapling height growth, leaf δ13C and δ18O, and foliar nitrogen concentration in the four most recent leaf cohorts were measured in dead and surviving saplings. The foliar isotopic composition of dead saplings (which reflects time-integrated leaf gas-exchange until mortality) displayed sharp increases in both δ13C and δ18O during the extreme drought of 2005, suggesting an important role of stomatal conductance (gs) reduction and diffusional limitations to photosynthesis in mortality. While P. nigra showed decreased growth in 2005 compared to the previous wetter year, P. sylvestris maintained similar growth levels in both years. Decreased growth, coupled with a sharper increase in foliar δ18O during extreme drought in dead saplings, indicate a more conservative water use strategy for P. nigra. The different physiological behavior of the two pine species in response to drought (further supported by data from surviving saplings) may have influenced 2005 mortality rates, which contributed to 2.4-fold greater survival for P. nigra over the lifespan of the saplings. This species-specific vulnerability to extreme drought could lead to changes in dominance and distribution of pine species in Mediterranean mountain forests. 相似文献
984.
Isabel Marques Antonio José Díaz‐Pérez José Ángel López‐Rodríguez Victoria Mirones Ana Sus Félix Llamas Alicia Alonso Ernesto Pérez‐Collazos Juan Viruel Elvira Sahuquillo Maria Del Carmen Sancho Benjamin Komac José Antonio Manso José Gabriel Segarra‐Moragues David Draper Luis Villar Pilar Catalán 《Botanical journal of the Linnean Society. Linnean Society of London》2013,173(4):676-706
The Iberian mountain spiny fescues are a reticulate group of five diploid grass taxa consisting of three parental species and two putative hybrids: F. × souliei (F. eskia × F. quadriflora) and F. × picoeuropeana (F. eskia × F. gautieri). Phenotypic and molecular studies were conducted with the aim of determining the taxonomic boundaries and genetic relationships of the five taxa and disentangling the origins of the two hybrids. Statistical analyses of 31 selected phenotypic traits were conducted on individuals from 159 populations and on nine type specimens. Molecular analyses of random amplified polymorphic DNA (RAPD) markers were performed on 29 populations. The phenotypic analyses detected significant differences between the five taxa and demonstrated the overall intermediacy of the F. × picoeuropeana and F. × souliei between their respective parents. The RAPD analysis corroborated the genetic differentiation of F. eskia, F. gautieri and F. quadriflora and the intermediate nature of the two hybrids; however, they also detected genetic variation within F. × picoeuropeana. These results suggest distinct origins for F. × picoeuropeana in the Cantabrian and Pyrenean mountains, with the sporadic Pyrenean populations having potentially resulted from recent hybridizations and the stabilized Cantabrian ones from older events followed by potential displacements of the parents. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 676–706. 相似文献
985.
Isabel Mateu‐Andrés Antoni Aguilella Fernando Boisset Rafael Currás Miguel Guara Emilio Laguna Antoni Marzo Mª Felisa Puche Joan Pedrola 《Botanical journal of the Linnean Society. Linnean Society of London》2013,171(4):700-712
Climate changes during the Quaternary had important effects on the evolution of European plant species. The distribution of genetic variability in rosemary, a strictly Mediterranean species of reputed Plio‐Quaternary origin for which the diversification centre is hypothesized to be located in the western part of the Mediterranean basin, was investigated across the species range by using plastid microsatellites [plastid simple sequence repeat (cpSSR)] markers. Seven out of the 17 primer pairs screened were polymorphic, with up to four alleles, yielding a total of 17 size variants combined into ten haplotypes. A permutation test to investigate for geographical structure showed no significant differences between RST and GST, indicating that the species lacks geographical structure. Low correlation between genetic and geographical distances was shown by the Mantel test. Bayesian analysis identified two coancestry groups of populations. The distribution of genetic diversity supports the hypothesized origin in the western Mediterranean basin, and with the demographic expansion test indicates three different routes of migration: a northern route expanding along the northern side of the Mediterranean and two southern routes, one from west to east through North Africa and reaching Cyrenaica, and a second to the south‐west of the Iberian Peninsula, from where it came back to the south–central areas. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013 , 171 , 700–712. 相似文献
986.
Revision of the section Anillochlamys Jeannel, 1909 (Coleoptera: Leiodidae: Cholevinae: Leptodirini)
José Ma Salgado 《法国昆虫学会纪事》2013,49(4):361-384
The taxonomy of the Iberian Leptodirini species of the section Anillochlamys Jeannel, 1909 has been revised. The proposed classification is based on the study of the genital structures of both sexes, in particular the internal sac of the aedeagus. According to the different models of internal sacs, the following genera, species and subspecies are identified: genus Anillochlamys Jeannel, 1909: A. aurouxi Español, 1965, A. bueni Jeannel, 1909 (= A. avariae Comas, 1977 n.syn.), A. cullelli Lagar, 1978, A. moroderi Bolívar, 1923 (= A. negrei Comas, 1990 n. syn.), A. subtruncatus Jeannel, 1930 (= A. baguenai Jeannel, 1930) and A. tropicus (Abeille, 1881) (= Adelops hispanicus Ehlers, 1893; A. tropicus var. apicalis Jeannel, 1909); genus Paranillochlamys Zariquiey, 1940: P. catalonicus (Jeannel, 1913), P. urgellesi (Español, 1965) and P. velox Zariquiey, 1940 (= P. velox montadai Lagar, 1963 n. syn.); genus Pseudochlamys Comas, 1977: P. raholai (Zariquiey, 1922) (= Anillochlamys raholai luis-bofilli Zariquiey, 1940 n. syn.); genus Spelaeochlamys Dieck, 1870 (= Typhlochlamys Español, 1975 n.syn.): S.bardisai (Español, 1975) (= Typhlochlamys escolai Comas, 1978 n. syn.), S. ehlersi Dieck, 1870 and S. ehlersi verai Comas, 1977 n. stat. 相似文献
987.
André Nel 《法国昆虫学会纪事》2013,49(1):23-29
A new deposit of Lower Cretaceous amber, found in Charente-Maritime (SW France) has yielded an important entomofauna with numerous arthropod associations characteristic of moist ground. We describe a new species of Dolichopodidae: ‘Microphorinae’(Diptera: Empidoidea), Microphorites deploegi n. sp. on the basis of seven male and female specimens of exceptional state of preservation. This genus was previously only known from Lebanese amber of the Lower Cretaceous. The present discovery supports a reconstruction of the palaeoenvironment as a sandy beach along the sea, under a warm climate. 相似文献
988.
The first fossil representative of the jewel damselflies (Calopterygoidea: Chlorocyphidae), a family of large, prominent, and often brilliantly colored Old World tropical Zygoptera, is described and figured. Chlorocypha cordasevae n. sp. was recovered from the Late Miocene (Early Pannonian, Serravalian to Tortonian, c.11 Ma) locality of Paldau, in the Styrian Basin, Austria. The fossil seems to be related to the African genus Chlorocypha Fraser, and within a larger group of African genera also including Stenocypha Dijkstra, Africocypha Pinhey, and Platycypha Fraser, and collectively set apart from southern Asiatic genera. The discovery of a central European species of Chlorocypha as recently as the Late Miocene reveals a much wider range to the family than its generally disjunctive modern distribution, demonstrating a Neogene contraction to their range, likely in connection with climatic cooling, drying, and developing seasonality. Modern chlorocyphids live under warm, humid climates, and the presence of C. cordasevae in the Pannonian fauna of Paldau further corroborates such a subtropical paleoclimate for the locality at that time. 相似文献
989.
András Szarka 《Acta Physiologiae Plantarum》2013,35(11):3245-3250
The reduction of dehydroascorbate, the oxidized form of ascorbate plays important role in the maintenance of sufficient level of ascorbate. In plant mitochondria two DHA reducing mechanisms, the GSH-dependent and the mitochondrial electron transfer chain dependent ascorbate recycling have been characterized. Although both pathways have been extensively studied quantitative information about the electron fluxes from one or another direction for the reduction of DHA is not known. The cellular, mitochondrial glutathione pools and mitochondrial DHA reducing capacity was measured in BSO treated and control tobacco cells. While BSO caused dramatic decrease of cellular GSH content the difference was much smoother at mitochondrial level. The difference in DHA reduction capacity was even smoother affirming the existence of alternative, non-GSH dependent DHA reducing mechanism(s) in plant mitochondria. On the base of the parallel determination of mitochondrial GSH content and ascorbate production upon DHA addition, GSH (consumption) is responsible for the ~ 20 % of ascorbate production. Almost 90 % enhancement of ascorbate production could be provoked by the addition of Complex II substrate succinate which could be almost totally prevented by the concomitant addition of malonate or TTFA. On the base of these results, the importance of mitochondrial Complex II compared to GSH-dependent mechanisms in mitochondrial ascorbate recycling has been underestimated so far. 相似文献
990.
Gládis de Oliveira Jucoski José Cambraia Cleberson Ribeiro Juraci Alves de Oliveira Sérgio Oliveira de Paula Marco Antonio Oliva 《Acta Physiologiae Plantarum》2013,35(5):1645-1657
In excess, iron can induce the production and accumulation of reactive oxygen species (ROS), causing oxidative stress. The objective of this work was to evaluate the impact of toxic concentrations of iron (Fe) on the antioxidative metabolism of young Eugenia uniflora plants. Forty-five-day-old plants grown in Hoagland nutrient solution, pH 5.0, were treated with three Fe concentrations, in the form of FeEDTA, during three periods of time. At the end of the treatment, the plants were harvested and relative growth rate, iron content, lipid peroxidation and enzymes and metabolites of the antioxidative metabolism were determined. Iron-treated plants showed higher iron contents, reduced relative growth rates and iron toxicity symptoms in both leaves and roots. There was an increase in lipid peroxidation with increasing Fe, only in the leaves. The enzymatic activities of superoxide dismutase (SOD) and glutathione reductase (GR) increased with increasing Fe concentration and treatment exposure time. The activities of catalase (CAT), peroxidase (POX) and ascorbate peroxidase (APX) also increased with increasing Fe concentration but decreased with increasing treatment exposure time. Glutathione peroxidase activity (GPX) decreased with increasing Fe concentration and exposure time. The ascorbate (AA) and reduced glutathione (GSH) contents and the AA/DHA and GSH/GSSG ratios, in general, increased with increasing Fe concentration and treatment exposure time. The results indicate that under toxic levels of Fe, young E. uniflora plants suffer increased oxidative stress, which is ameliorated through changes in the activities of antioxidative enzymes and in the contents of the antioxidants AA and GSH. 相似文献