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1.
Sci Total Environ ; 756: 143795, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33302079

RESUMO

Tropospheric ozone (O3) levels are still elevated in many regions of the world including Northern Hemisphere forests areas, and are predicted to increase further due to anthropogenic activities and climate change. Oaks are major woody angiosperms in the Northern Hemisphere in terms of biodiversity, ecological dominance, and economic values. This meta-analysis shows overwhelming evidence of the O3 effects on 51 growth, anatomical, biomass, physiological and biochemical parameters of 14 deciduous or evergreen oak species distributed all around the Northern Hemisphere. Although no large impacts were observed on biomass, suggesting an O3 tolerance by oaks, some impairments were found at physiological level that might negatively affect carbon sequestration and water vapour transfer to the atmosphere. This outcome suggests the need to incorporate this phenomenon into future projection studies dealing with how atmospheric change and forest biomes will interact in effecting climatic change. Among the antioxidants used by oaks to respond to O3, phenols seem to have a crucial role. Deciduous species resulted more affected by O3 than evergreen ones, as well as oaks native to Eurasia, in comparison with those from North-America. Experiments performed in less controlled environments showed more O3 deleterious effects, especially under higher AOT40 levels, but negative impacts were also reported for acute O3 exposures. Most of the reviewed studies with additional treatments to O3 exposure investigated the interaction(s) between O3 and drought, but the negative effects induced by drought seemed not to be exacerbated by the pollutant. However, more combined experiments on the impact of O3 and co-occurring stressors on woody species are necessary. Another major issue is the lack of experiments on adult trees. To better understand O3 impacts, and to reinforce the strength of O3 impact predictions, O3 controlled experiments on young individuals should be combined with long-term experiments on mature trees grown in open-air conditions.


Assuntos
Ozônio , Quercus , Florestas , Humanos , América do Norte , Ozônio/toxicidade , Folhas de Planta , Árvores
2.
Bioresour Technol ; 322: 124519, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33338943

RESUMO

Lignocellulosic biomass processing employing ionic liquids is of recent research interest for the biorefinery industry. The data on biomass dissolution kinetics in ionic liquids is important for designing scale-up pre-treatment reactor design. In this study, the reaction mechanism and kinetics of oak wood dissolution in aqueous choline chloride was investigated. In an extended effort, a correlation of dimensionless numbers was developed for the estimation the mass transfer coefficient. The analyses suggested that oak wood dissolution in choline chloride occurred in two stages. The diffusion of ionic liquid through the product layer was the dominating rate-controlling step in the first stage of dissolution followed by the surface chemical reaction in the second stage. The diffusivity of choline chloride into the oak wood matrix was ranging between 2.96E-14 and 2.84E-13 m2/s. The activation energy of the diffusion controlled stage and surface chemical reaction controlled stage was approximately 24.2 and 40.3 kJ mol-1, respectively. The proposed mathematical correlation for mass transfer coefficient fitted well with the experimental mass transfer coefficient values.


Assuntos
Quercus , Madeira , Colina , Cinética , Solubilidade
3.
Food Chem ; 340: 127573, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33032144

RESUMO

Cabernet Sauvignon wines were aged for 15 months in used and new French 225 L oak barrels, followed by a period of 3 months in bottle. In addition to control barrels (3 years old), three bending/toasting protocols, including fire bent and fire toasted (fire-bent); water bent and fire toasted (water-bent); and a hybridized method based on fire bending and toasting followed by a 12 h fill with water at 80 °C (fire-bent + hot water), were trialed in triplicate. Parameters such as acetic acid and alcohol content (higher in control wines), and anthocyanins, color and polymeric pigments (higher in wines aged in the new barrels), were more affected by barrel use (new versus neutral) than by bending/toasting protocols. At the end of the study (day 602), only 4-vinyl-guaiacol, eugenol and cis-lactone showed odor activity values (OAV's) above 1, with the latter being the most relevant odor active compound across treatments whereas eugenol was 10-fold higher in the water-bent wines. Principal component analysis (PCA) including phenolics and volatile compounds suggested differences between wines aged in control and new barrels, but less clear-cut differences within wines aged in barrels produced with the different bending/toasting protocols.


Assuntos
Indústria de Processamento de Alimentos/instrumentação , Quercus , Vitis , Vinho/análise , Antocianinas/análise , Cor , Eugenol/análise , Análise de Alimentos/estatística & dados numéricos , Manipulação de Alimentos , Indústria de Processamento de Alimentos/métodos , Guaiacol/análogos & derivados , Guaiacol/análise , Lactonas/análise , Odorantes/análise , Fenóis/análise , Análise de Componente Principal , Compostos Orgânicos Voláteis/análise
4.
Food Chem ; 338: 127804, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32798823

RESUMO

This work investigates the release of toxic elements from wood into the experimental spirit models and the safety risks for consumers. The spirit models were prepared as ethanolic extracts using the procedure which reproduces maturation of spirits. Investigation included staves of wood species commonly used in Balkan cooperage: mulberry, Myrobalan plum, black locust, wild cherry, and various oaks. Potassium was the most abundant element, except in the wild cherry extract where calcium was dominant, and the Myrobalan plum extract where phosphorus was the most abundant. The parameters for the health risk assessment, such as hazard index (HI) and hazard quotient (HQ) were calculated for potentially toxic elements and indicated that all wood extracts would be safe for human consumption. Owing to the proven abundance of phenolics in the investigated wood extracts, relations among elements and phenolics were also studied and conclusions were made based on the statistically significant correlations.


Assuntos
Extratos Vegetais/química , Extratos Vegetais/toxicidade , Madeira/química , Península Balcânica , Carcinógenos/análise , Etanol/química , Humanos , Resíduos Industriais , Metais/análise , Metais/toxicidade , Morus/química , Nível de Efeito Adverso não Observado , Fenóis/análise , Fósforo/análise , Extratos Vegetais/análise , Potássio/análise , Quercus/química , Medição de Risco
5.
Food Chem ; 338: 127803, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32822899

RESUMO

Quercus acorns have been used as a staple food since archeological times; currently, there is a renewed interest in the direct use of the acorns as nuts or as a source of consumable flour. In this regard, the phytochemical composition and variability of various morphotypes of acorns from Quercus ilex have been determined by using two platforms, near infrared spectroscopy (NIRS) and mass spectrometry (MS)-based metabolomics. According to NIRS, starch was the most abundant compound (50-60%). UHPLC-QToF analysis was used for untargeted metabolomic analysis and 192 metabolites were annotated. Principal component analysis (PCA) discriminated the morphotypes; 50 compounds out of 192 identified had the highest load over the first two PCA components (explaining 67.2% variability) and can be potential markers of variability. The data presented here support the value of acorns as a source of nutritionally rich compounds thus justifying their use a good alternative to other nuts.


Assuntos
Compostos Fitoquímicos/análise , Quercus/química , Sementes/química , Sementes/fisiologia , Cromatografia Líquida de Alta Pressão , Análise de Componente Principal , Quercus/metabolismo , Sementes/anatomia & histologia , Espectroscopia de Luz Próxima ao Infravermelho , Amido/análise , Espectrometria de Massas em Tandem
6.
Phytochemistry ; 181: 112570, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33166753

RESUMO

The cutin content and composition of cork oak (Quercus suber) leaves was determined in six provenances with different seed geographical origin spreading across the species natural distribution. The cutin layer on the leaf surface was on average 518 µg/cm2 of leaf area and represented 6.7% of the leaf dry weight, with no significant differences among provenances. Cutin depolymerisation was carried out by transesterification on whole leaves. The cutin composition of cork oak leaves is presented here for the first time. It is essentially composed of long-chain aliphatic ω-hydroxy fatty acids (44.4% of the total monomers), mostly with mid-chain hydroxyl and epoxy groups, fatty acids (20.7%), and a smaller proportion of α,ω-dicarboxylic acids (6.5%). The predominant compounds are 10,16-dihydroxy hexadecanoic acid (17.7-25.2%) and 9,10,18-trihydroxyoctadecanoic acid (15.6-18.0%). Alkanols represent 2.8% and aromatic compounds 12.8%, mainly coumarates. Isolation of cuticles from Q. suber leaves was performed using an enzymatic separation procedure and the fragments were analysed. Cuticle isolation is difficult and direct depolymerisation applied to whole leaves proved a suitable method to study cutin monomeric composition, which did not differ substantially to that of the isolated cuticles. No differences between provenances were found regarding cutin content and composition, thereby ruling out a significant genetic determination of these traits, but rather a highly adaptive phenotypic plasticity of cork oak. Although overall similar in their chemical nature, cutin and suberin in cork oak differ in the proportion of the major chemical families, i.e. ω-hydroxy acids, α,ω-diacids, and fatty acids.


Assuntos
Quercus , Ácidos Graxos , Lipídeos de Membrana , Folhas de Planta
7.
Chemosphere ; 263: 127859, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32841871

RESUMO

The aim of the study was to evaluate the effect of dimethylarsinic acid (DMA) on growth parameters and levels of stress-related metabolites in Acer pseudoplatanus, Betula pendula and Quercus robur. The increase of DMA concentration in the solution led to a notable growth retardation of trees. An intense As accumulation (mainly As(III) and As(V)) expressed as BCF and TF > 1 was recorded only for Q. robur. Generally a decrease in contents of cellulose, hemicellulose and holocellulose with a simultaneous increase in lignin content were recorded. Phenolic composition of leaf extracts was modified by DMA, while root and rhizosphere extracts were poor in phenolics. Toxicity of DMA leads to a significant drop in salicylic acid content in leaves observed at lower doses. Higher DMA levels caused a second, probably ROS-derived depletion of the metabolite accompanied with a severe growth retardation, most pronounced in the case of B. pendula. DMA caused the inhibition of LMWOA biosynthesis in roots of A. pseudoplatanus, B. pendula and their exudation into the rhizosphere, while in Q. robur roots and leaves a stimulation of their accumulation was observed. Disturbances in the activity of enzymatic antioxidants were observed for all the species following the increasing level of DMA.


Assuntos
Acer , Arsênico , Quercus , Betula , Ácido Cacodílico , Folhas de Planta , Árvores
8.
Ying Yong Sheng Tai Xue Bao ; 31(11): 3605-3613, 2020 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-33300709

RESUMO

We analyzed the spatial heterogeneity of plant species diversity in shrub layers and its relationship with light environment in Quercus variabilis plantation and Q. variabilis-Platycladus orientali mixed forest, following the method of geostatistics. The results showed that plant species diversity indices (Shannon H, Simpson Ds, Margalef Ma) of shrub layers in Q. variabilis plantation were significantly lower than that in Q. variabilis-P. orientalis mixed forest. The variation ranges and spatial autocorrelation distances of plant species diversity index in Q. variabilis plantation were higher than that in Q. variabilis-P. orientalis mixed forest, with lower spatial homogeneity but stronger spatial dependence. The plant species diversity indices of H, Ds and Ma structural ratios of shrub layers in Q. variabilis pure forest were 44.2%-49.7%, with moderate spatial autocorrelation. The structure ratios of H, Ds and Ma in Q. variabilis-P. orientalis mixed forest were 1.5%-3.3%, with strong spatial autocorrelation. The spatial distribution of biodiversity showed obvious strip-like gradient trend in Q. variabilis plantation and patchy gradient change in Q. variabilis-P. orientalis mixed forest, suggesting that the spatial continuity of plant species of shrub layers was worse in Q. variabilis-P. orientalis mixed forest and that the spatial variation was stronger than that in Q. variabilis pure forest. Results of correlation analysis and stepwise regression analysis showed that the total light and plant canopy openness were the most significant factors affecting plant species diversity of shrub layers in both forest types. Light environment formed by plant canopy structure played a crucial part in maintaining plant diversity in shrub layer.


Assuntos
Quercus , Biodiversidade , Florestas , Plantas , Árvores
9.
Ying Yong Sheng Tai Xue Bao ; 31(10): 3331-3339, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33314822

RESUMO

The effects of seed size and drought stress on the growth and physiological characteristics of Quercus wutaishanica seedlings were investigated under shading conditions of a pot experiment in greenhouse. There were four treatments, including 80% field water content (FWC), 60% FWC, 40% FWC, and 20% FWC [CK, light drought stress (LDS), medium drought stress (MDS), and high drought stress (HDS), respectively]. The results showed that leaf area per plant, total dry mass, and root-shoot ratio of Q. wutaishanica seedlings regenerated from large seeds (3.05±0.38 g) were significantly higher than those from small seeds (1.46±0.27 g) in all four treatments. Shoot height, basal stem diameter, leaf number, specific leaf area, relative growth rate, and net assimilation rate of the seedlings from large seeds were higher than those of seedlings from small seeds under the treatments of LDS, MDS and HDS. Activities of peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD) in large-seeded seedlings were higher than those of small-seeded seedlings under all treatments, while the contents of MDA, soluble protein, free proline, and total chlorophyll of large-seeded seedlings were higher than those of small-seeded seedlings only under some drought stress treatments. All growth parameters except the root-shoot ratio decreased with the increases of drought stress. The HDS treatment resulted in 19.4% and 20.0% decline in total dry mass of large- and small-seeded seedlings respectively, compared with those of CK. With increasing drought stress, the activities of POD, CAT, and SOD decreased after an initial increase. POD activity of large- and small-seeded seedling under MDS treatment was 126.7% and 142.1% higher than CK, while CAT was 170.0% and 151.9% higher than CK, respectively. However, the MDA content of seedlings from large and small seeds under HDS treatment was 86.5% and 68.9% higher than that of CK, respectively. The contents of soluble protein, free proline, and total chlorophyll rose at first and then fell with increasing drought stress, and soluble protein content in large- and small-seeded seedlings experienced MDS enhanced 320.7% and 352.7%, respectively. Those results indicated that large-seeded seedlings of Q. wutaishanica had stronger drought tolerance than small-seeded seedlings due to their growth and physiology advantages. Large-seeded seedlings with stronger resistance to drought stress should be applied to artificial regeneration of the degraded secondary Q. wutaishanica plantations.


Assuntos
Quercus , Plântula , Clorofila , Secas , Sementes , Estresse Fisiológico
10.
Zootaxa ; 4890(3): zootaxa.4890.3.9, 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33311123

RESUMO

Two new species of oak gall wasps, Cynips izzetbaysali sp. nov. and Callirhytis afion sp. nov. (Hymenoptera: Cynipidae: Cynipini) are described from Turkey. The new Cynips species is known only from asexual females and induces detachable leaf galls on Quercus infectoria. The sexual generation of the new Callirhytis species is known to induce acorn galls on Quercus cerris. Data on the diagnosis, distribution, and biology of the two new species are given.


Assuntos
Himenópteros , Quercus , Vespas , Animais , Feminino , Folhas de Planta , Turquia
11.
Zootaxa ; 4881(1): zootaxa.4881.1.7, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33311132

RESUMO

Fifteen parasitoids of Massicus raddei (Blessig Solsky) (Coleoptera, Cerambycidae) are revised. The host is a serious pest of Quercus liaotungensis Koidz. and Q. mongolica Fisch. ex Ledeb. in NE China. All the parasitoids were reared from larvae of M. raddei. Pseudocyanopterus gen. nov. raddeivorus sp. nov., a new braconid wasp is described, and Cyanopterus tricolor (Ivanov) and Eubazus (E.) pallipes are new records for the Chinese fauna. An identification key to the parasitoids of M. raddei in China is provided. Detailed photographs of the parasitoids are provided.


Assuntos
Besouros , Quercus , Vespas , Animais , China , Larva
12.
Zootaxa ; 4890(4): zootaxa.4890.4.7, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33311109

RESUMO

A new sexual form of a gallwasp, Andricus forni Pujade-Villar Nicholls n. sp., is described from China (Zhejiang province) based on males, females and galls collected on Quercus serrata. Data on the morphology, diagnosis, distribution and biology of the new species are provided. Molecular data are also provided to support this species. A key to Asian Andricus gallwasp species with similar integral leaf galls is presented. Finally we discuss the taxonomic status of Asian Andricus making these integral leaf galls, including uncertainty on the validity of both Andricus quercicola and A. marmoratus.


Assuntos
Himenópteros , Quercus , Vespas , Animais , China , Feminino , Folhas de Planta
13.
PLoS One ; 15(11): e0241501, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33141873

RESUMO

Little information exists on songbird roosting habits and the types of habitats that songbirds select. To better understand a species' habitat requirements, all aspects of its biology should be studied. The Cerulean Warbler (Setophaga cerulea, Wilson) is a Nearctic-Neotropical migrant that is a species of conservation concern across its range. It is one of the fastest declining species of wood-warbler (Parulidae) in North America. Since 2007, a breeding population of Cerulean Warblers has been monitored in southern Indiana, as part of the Hardwood Ecosystem Experiment. The Hardwood Ecosystem Experiment is a 100 yr project that studies the effects of different forest management practices on plant and animal communities. During the 2017 breeding season, 10 male Cerulean Warblers were tracked to roost locations. Roost sites selected by male Cerulean Warbler were characterized with less basal area, higher canopy cover, greater grapevine (Vitis spp., L.) presence, less shrubs, steeper slopes, and less white oak (Quercus alba, L.) abundance. With this new knowledge we can incorporate additional features of habitat in the formulation of a management plan for this declining species.


Assuntos
Ecossistema , Comportamento de Nidação/fisiologia , Passeriformes/fisiologia , Animais , Geografia , Indiana , Masculino , Modelos Teóricos , Quercus
14.
Oecologia ; 194(4): 771-780, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33159540

RESUMO

Osmoderma eremita is a species of beetle that inhabits hollows in ancient trees, which is a habitat that has decreased significantly during the last century. In southeastern Sweden, we studied the metapopulation dynamics of this beetle over a 25 year period, using capture-mark-recapture. The metapopulation size had been rather stable over time, but in most of the individual trees there had been a positive or negative trend in population development. The probability of colonisation was higher in well-connected trees with characteristics reflecting earlier successional stages, and the probability of extinction higher in trees with larger diameter (i.e. in later successional stages), which is expected from a habitat-tracking metapopulation. The annual tree mortality and fall rates (1.1% and 0.4%, respectively) are lower than the colonisation and extinction rates (5-7%), indicating that some of the metapopulation dynamics are due to the habitat dynamics, but many colonisations and extinctions take place for other reasons, such as stochastic events in small populations. The studied metapopulation occurs in an area with a high density of hollow oaks and where the oak pastures are still managed by grazing. In stands with fewer than ten suitable trees, the long-term extinction risk may be considerable, since only a small proportion of all hollow trees harbours large populations, and the population size in trees may change considerably during a decade.


Assuntos
Besouros , Quercus , Animais , Ecossistema , Dinâmica Populacional , Suécia
15.
PLoS One ; 15(10): e0241061, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33095813

RESUMO

We measured 34 years of plant community change in a degraded oak woodland undergoing ecological management. Management included regular prescribed fire, control of white-tailed deer populations, repeated sowing of a diverse seed mix, and removal of invasive plants. We tracked change with several conservation metrics. Time series analysis showed no significant changes over time in either plant species richness or the Shannon-Weiner diversity index. Floristic Quality Assessment measures-the Floristic Quality Index (FQI), Cover-weighted FQI, and the Mean Coefficient of Conservatism (Mean C)-all increased dramatically over time, such that their values now surpass those of the highest quality representative of this habitat in the region. Cover-weighted FQI had the added benefit of being quick to respond (negatively and positively) to short-term management changes during the study. This sensitivity highlights its utility for adaptive management, enabling timely, data-driven changes to ongoing management regimes. Plant community composition showed striking changes during the study period, as species of high conservation value replaced weedier species. As a group, conservative woodland species are notoriously slow to recover from degradation, making this flora's recovery particularly notable. A mid-study cessation of management immediately stalled the woodland's recovery according to Floristic Quality metrics, but the restoration quickly returned to its positive trajectory with the resumption of management treatments. These results illustrate that impressive plant biodiversity restoration can be achieved, even in highly degraded contemporary oak ecosystems, if ecological management is comprehensive and if it is sustained over time.


Assuntos
Florestas , Quercus , Desenvolvimento Sustentável , Distribuição Animal , Animais , Cervos , Fogo , Illinois , Espécies Introduzidas , Dispersão Vegetal
16.
Mol Ecol ; 29(23): 4503-4505, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33070388

RESUMO

It is well established that biotic-interspecific interactions, such as competition, mutualism, parasitism or predation, modulate species dynamics in demographic and evolutionary terms. It is also acknowledged that biotic interactions can even have major effects on local population dynamics and scale-up to determine wider species' ranges (Wisz et al., 2013). Notwithstanding, the study of biotic interactions has been mostly ignored in biogeography and phylogeography research, for which it has been long assumed that abiotic factors (e.g. climate) mostly drive the ecological and evolutionary processes that underlie species' distribution. Consequently, our knowledge is scarce about the role of biotic interactions in determining spatial patterns of genetic diversity and structure. In a From the Cover article in this issue of Molecular Ecology, Ortego & Knowles (2020) address the study of positive and negative plant-plant interactions and test whether their demographic consequences translate into broadscale patterns of genomic variation in two oak species from the iconic California Floristic Province. The integrative approach undertaken in this study reveals that some models that incorporate competition or facilitation better explain genomic patterns than null models in which species respond only to variations in environmental suitability. These findings highlight the relevance of biologically informed model-based approaches for inferring the evolutionary consequences of species' range dynamics, which is of particular importance in today's global change context.


Assuntos
Quercus , Animais , Clima , Mudança Climática , Ecossistema , Filogeografia
17.
Zootaxa ; 4860(2): zootaxa.4860.2.2, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33056161

RESUMO

A complete taxonomic assessment of the inquiline fauna (Hymenoptera: Cynipidae: Synergini, Ceroptresini) reared from cynipid oak galls collected in South Korea is conducted for the first time. Previously, six species were known from this country (Ceroptres kovalevi Belizin, 1973; Synergus chinensis Melika, Ács Bechtold, 2004; Synergus japonicus Walker, 1874; Ufo koreanus Melika, Pujade-Villar Choi, 2007; and presumably, Saphonecrus chaodongzhui Melika, Ács Bechtold, 2004 and Ufo cerroneuroteri Tang Melika, 2012). The study of new material reared from cynipid galls collected from oaks (Quercus spp.) from various locations throughout South Korea has increased the total number of inquiline species known from this country to 14, of which seven are new country records (Saphonecrus shirakashii (Shinji, 1940); Sa. symbioticus Melika Schwéger, 2015; Synergus abei Melika Schwéger, 2015; S. belizinellus Schwéger Melika 2015; S. formosanus Schwéger Melika, 2015; S. ishikarii Melika Schwéger, 2015; and S. symbioticus Schwéger Melika, 2015), and one is a new species: Synergus minutus Lobato-Vila Pujade-Villar, sp. nov. The new species is formally described and illustrated. New biological and distribution data are provided for both the newly recorded species and the other reared species. The Korean fauna is compared with that from other countries within the Eastern Palearctic and the Oriental regions.


Assuntos
Himenópteros , Quercus , Animais , República da Coreia
18.
Zootaxa ; 4786(2): zootaxa.4786.2.8, 2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-33056488

RESUMO

Specimens of an ambrosia beetle, Xyleborus monographus (Fabricius), were found infesting oak trees in California. This is the first record of this species established in North America. Based on collection information, this species most likely has been established in the Napa County area for several years. A modified key to Xyleborus in North America, and diagnosis of the species is provided.


Assuntos
Ambrosia , Besouros , Quercus , Gorgulhos , Animais , California
19.
Zootaxa ; 4802(2): zootaxa.4802.2.6, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-33056621

RESUMO

Field surveys were carried out to determine the richness of the Cynipidae fauna of Kazdagi National Park, located on the border of Edremit county (Balikesir province, Turkey). Gall samples of cynipids were collected or photographed on Quercus and Rosa host plants. As a result, 53 cynipid species belonging to 3 different tribes were found or observed in the surveyed area. 14 and 8 species were recorded as new for the Cynipidae fauna of Balikesir and Çanakkale provinces respectively, including the first locality record of Andricus hystrix Trotter, 1897 for Turkey. In addition, color photos of reared cynipid wasps from their galls and the observed cynipid galls on their host plant species are presented.


Assuntos
Quercus , Vespas , Animais , Parques Recreativos , Plantas , Turquia
20.
PLoS One ; 15(10): e0239755, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33052951

RESUMO

Knowledge of the recruitment of dominant forest species is a key aspect for forest conservation and the ecosystem services they provide. In this paper, we address how the simultaneous action of climate change and the intensity of land use in the past influence the recruitment of a forest species that depends on the provision of nurse plants to recruit. We compared the number of saplings (up to 15 years old) and juveniles (16 to 50 years old) of Quercus ilex in 17, 5.3 ha plots in the Iberian System (eastern Spain). We used a gradient of past deforestation intensity crossed with two levels of average annual precipitation, one of them at the lower limit of the species' precipitation niche (semi-arid) and the other at the optimum (sub-humid). We also examined the association between recruits and nurse plants and the effect on this association of plot-scale factors, such as seed abundance (reproductive Q. ilex), microsites (nurse species and soil availability), and large herbivores. The increase in aridity in the last decades has drastically reduced the recruitment of new individuals in the forests of Q. ilex located in the lower limit of their precipitation niche, regardless of the intensity of past deforestation that they suffered. Recruitment in these climatic conditions depends almost exclusively on large trees and shrubs whose abundance may also be limited by aridity. The lack of regeneration questions the future of these populations, as the number of individuals will decrease over time despite the strong resistance of adult trees to disturbance and drought.


Assuntos
Secas , Ecossistema , Quercus/fisiologia , Regeneração/fisiologia , Mudança Climática , Conservação dos Recursos Naturais/métodos , Florestas , Herbivoria/fisiologia , Estações do Ano , Solo , Espanha , Árvores/fisiologia , Água
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