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2.
PeerJ ; 10: e14212, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36530400

RESUMO

Premise: The recognition of the Miocene Climate Optimum (MCO) in terrestrial palaeoenvironments of the Eastern Mediterranean is restricted to Lesbos and Lemnos Islands, Greece. This area is significant for its wood microfossils. A recently-discovered fossil wood assemblage from Gökçeada (Imbros) Island, Turkey, including tree species similar to the Greek findings, is thought to have an early Miocene age. Here, we revise the age of the latter plant fossiliferous locality, re-evaluate the area for the study of MCO for the terrestrial palaeoecosystems of the Eastern Mediterranean and the nomenclature errors referring to the occurrence of fossil wood. We present the plant-insect-environment interactions using detailed anatomical descriptions, of an extinct conifer and its extinct cambium miner feeding traces observed in its secondary xylem. Methods: Three thin sections were prepared with standard palaeoxylotomical techniques from a small section of the silicified wood; the sections were observed under a light microscope. The anatomy of the conifer and its damage patterns were compared with those of extant and fossil Cupressaceae and Agromyzidae, respectively. Pivotal results: The common anatomical features of the studied wood specimen and Hesperocyparis macrocarpa (Hartw.) Bartel and a shared characteristic (the number of the cross-field pits - a feature we consider of diagnostic value) with Xanthocyparis vietnamensis Farjon & T.H. Nguyên led to its assignment to the Hesperocyparis-Xanthocyparis-Callitropsis clade. The detailed study of the wound scars and anatomical abnormalities, the anatomical-environmental associations, and structural-functional reactions follow the identification of the wood's anatomy sensu Carlquist providing decisive results. Conclusions: Based on the distinctive characteristics presented, we identify our macrofossil as Cupressinoxylon matromnense Grambast, a stem or an extinct lineage of the Hesperocyparis-Xanthocyparis vietnamensis-Callitropsis nootkatensis clade with feeding traces of the fossil cambium miner of the genus Protophytobia Süss (Diptera: Agromyzidae), and anatomical damage and reaction tissue on adventitious shoots. The use of Protopinaceae and Pinoxylon F. H. Knowlton from the eastern Mediterranean are re-evaluated and corrections are provided. The age of the studied plant fossiliferous locality in Gökçeada is revised as middle Miocene, allowing the proposal of an eastern Mediterranean MCO hotspot, including Lesbos, Lemnos, and Gökçeada (Imbros) Islands.


Assuntos
Cupressaceae , Dípteros , Animais , Câmbio , Turquia , Árvores
3.
Environ Monit Assess ; 195(1): 196, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36512115

RESUMO

This study was conducted to examine the land cover (LC)/land use (LU) change affecting forest and seminatural ecosystems and the spatio-temporal development of urban expansion between 1990 and 2018 in the city of Istanbul, where urbanization is the most intense in Turkey. For this purpose, using Corine Land Cover (1990, 2000, 2006, 2012, and 2018) dataset, the land cover of the area was determined in 5 different classes (artificial surface, agriculture, forest, water bodies, water), maps were produced, and tabular data were created. The changes in LC/LU between 1990 and 2018 were determined according to the Puyravaud land cover change rate and hot spot analysis methods. According to our findings, we determined that urbanization in Istanbul expanded the most in the east-west direction, and the agricultural and forest areas gradually decreased by 3.02% and 6.66% respectively; urban areas increased at the same rate of 9.69%. It is predicted that this change will continue increasing until 2030 when the forecasting method is applied in the field. It has been determined that the most important reasons for this situation are local government policies, population growth, and economic development initiatives applied in the area. As a result, it has emerged that measures should be taken based on sustainability and naturalness approaches to design urban development plans and to protect natural areas on a large scale, in order to limit possible LC/LU conversion from natural structure to urbanization in the area.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Turquia , Monitoramento Ambiental/métodos , Florestas , Urbanização , Agricultura , Água
4.
Int J Biometeorol ; 64(5): 803-813, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32144486

RESUMO

The history of climate is crucially important for any part of the world to understand the nature of climate change. In this context, precipitation reconstruction is still lacking in northern Kazakhstan. The purpose of this study is to present a reconstruction for the total precipitation of October of the previous year to July of the current year in northern Kazakhstan. Pinus sylvestris L. (Scots pine) forests in Burabai Region are quite important to collect samples to study the climate history. A regional chronology, covering the years of 1702-2014 of Pinus sylvestris constructed by using 289/466 trees/cores was used in the reconstruction. The gridded climate data for the years of 1950-2014 were used in the calibration and verification process. High and significant correlations were obtained between tree-ring widths and October to July precipitation in Burabai Region. Based on this significant relationship, reconstruction was performed for the years of 1744-2014. Adjusted R2, F-value, sign test, and r value were found as 0.38, 39.7 (P ≤ 0.001), 47+/17, and 0.62 for reconstruction, respectively. The reconstruction showed that 43 dry and 42 wet years occurred during the years of 1744-2014. Only a one-time four-year duration of the wet period was determined covering the years 1978-1981. However, three of six very dry years occurred after the 1950s. As a conclusion, extremity in recent decades is getting an increase in Burabai region.


Assuntos
Pinus sylvestris , Pinus , Mudança Climática , Florestas , Cazaquistão , Árvores
5.
Asian Pac J Allergy Immunol ; 37(4): 205-211, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30447650

RESUMO

BACKGROUND: Tree pollens are well-known aeroallergens all over the world. Little is known about the allergenicity of Morus alba (white mulberry) pollen. OBJECIVE: We aimed to explore the potential allergens of this pollen and its clinical relevance in tree pollen allergic patients living in Istanbul, Turkey. METHODS: Twenty three seasonal allergic rhinitis patients with a confirmed tree pollen allergy and 5 healthy control subjects underwent skin prick and nasal provocation tests with M.alba pollen extract. The pollen extract was then resolved by gel electrophoresis, and immunoblotted with sera from patients/control individuals to detect the potential allergenic proteins. The prevalent IgE binding proteins from 1D-gel were analyzed by MALDI-TOF/TOF. RESULTS: Eleven out of 23 patients were reactive to the extract with skin prick tests. Seven of those patients also reacted positively to the nasal provocation tests. The most common IgE-binding pollen proteins were detected between 55-100 kDa, and also at molecular weights lower than 30 kDa for some patients. Mass spectrometry analyses revealed that the principal IgE-binding protein was methionine synthase (5-methyltetrahydropteroyltriglutamate homocysteine methyltransferase), which is then proposed as a novel allergen in M.alba pollen. CONCLUSION: This study provides the first detailed information for the potential allergens of Morus alba pollen of Istanbul. Methionine synthase with an apparent molecular weight of 80 to 85 kDa has been recognized as one of the allergens in Morus alba pollen for the first time.


Assuntos
Alérgenos/imunologia , Antígenos de Plantas/imunologia , Morus/imunologia , Proteínas de Plantas/imunologia , Pólen/imunologia , Rinite Alérgica Sazonal/imunologia , Adulto , Feminino , Humanos , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Testes de Provocação Nasal , Proteômica , Rinite Alérgica Sazonal/sangue , Rinite Alérgica Sazonal/diagnóstico , Testes Cutâneos , Adulto Jovem
6.
Int J Biometeorol ; 57(5): 691-701, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23015281

RESUMO

We developed a high quality reconstruction of May-June precipitation for the interior region of southwestern Turkey using regional tree-ring data calibrated with meteorological data from Burdur. In this study, three new climate sensitive black pine chronologies were built. In addition to new chronologies, four previously published black pine chronologies were used for the reconstruction. Two separate reconstructions were developed. The first reconstruction used all site chronologies over the common interval AD 1813-2004. The second reconstruction used four of the chronologies with a common interval AD 1692-2004. R² values of the reconstructions were 0.64 and 0.51 with RE values of 0.63 and 0.51, respectively. During the period AD 1692-1938, 41 dry and 48 wet events were found. Very dry years occurred in AD 1725, 1814, 1851, 1887, 1916, and 1923, while very wet years occurred in AD 1736, 1780, 1788, 1803, and 1892. The longest dry period was 16 years long between 1860 and 1875. We then explored relationships between the reconstructed rainfall patterns and major volcanic eruptions, and discovered that wetter than normal years occurred during or immediately after the years with the largest volcanic eruptions.


Assuntos
Interpretação Estatística de Dados , Modelos Estatísticos , Chuva , Estações do Ano , Árvores/anatomia & histologia , Árvores/crescimento & desenvolvimento , Erupções Vulcânicas/estatística & dados numéricos , Simulação por Computador , Ecossistema , Estatística como Assunto , Turquia
7.
J Environ Biol ; 28(1): 73-5, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17717989

RESUMO

This study was carried out to investigate the relationship between tree ring widths of Pinus nigra in Kazdaglari having humid and very humid climatic conditions. Sixty two trees were cut from 24 sampled points from different altitudes in Kazdaglari to measure treering widths. To determine the responses to the climate, correlation coefficients between treering widths and climatic data were calculated during biological years from October of the previous year to September of the current year In lower altitudes, where climate type is humid, spring and summer precipitation affect the growth of tree rings, but they are not statistically limiting factors. In higher altitudes, this effect is weaker. As a result, we can conclude that the negative effects of the drought are still not clear on the Pinus nigra trees under humid and very humid climatic conditions and at the northern slopes in submediterranean mountainous regions in Turkey.


Assuntos
Pinus/crescimento & desenvolvimento , Altitude , Desastres , Efeito Estufa , Umidade , Chuva , Temperatura , Turquia
8.
Int J Biometeorol ; 49(5): 297-302, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15635479

RESUMO

Tree-ring data for Turkey are crucial to the understanding of the climatological effect of drought and rainfall from one era to the next. To this end, the present study reconstructed precipitation patterns in the western Black Sea region of Turkey. Tree-ring widths of oak trees were used to reconstruct March-June precipitation patterns for the years A.D. 1635-2000. According to the findings, during the past four centuries drought events in this region persisted for no more than 2 years, and extreme dry and wet events occurred generally in 1-year intervals. Historical records of droughts in Anatolia and neighboring countries corroborate the data furnished by tree-ring widths to indicate that major droughts and famine events occurred in 1725, 1757, 1887, 1890-1891, 1893-1894 and 1927-1928.


Assuntos
Clima , Quercus/crescimento & desenvolvimento , Chuva , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , Estações do Ano , Turquia
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