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1.
Sci Rep ; 14(1): 7784, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565553

RESUMO

In Iran, native oak species are under threat from episodes of Charcoal Disease, a decline syndrome driven by abiotic stressors (e.g. drought, elevated temperature) and biotic components, Biscogniauxia mediterranea (De Not.) Kuntze and Obolarina persica (M. Mirabolfathy). The outbreak is still ongoing and the country's largest ever recorded. Still, the factors driving its' epidemiology in time and space are poorly known and such knowledge is urgently needed to develop strategies to counteract the adverse effects. In this study, we developed a generic framework based on experimental, machine-learning algorithms and spatial analyses for landscape-level prediction of oak charcoal disease outbreaks. Extensive field surveys were conducted during 2013-2015 in eight provinces (more than 50 unique counties) in the Zagros ecoregion. Pathogenic fungi were isolated and characterized through morphological and molecular approaches, and their pathogenicity was assessed under controlled water stress regimes in the greenhouse. Further, we evaluated a set of 29 bioclimatic, environmental, and host layers in modeling for disease incidence data using four well-known machine learning algorithms including the Generalized Linear Model, Gradient Boosting Model, Random Forest model (RF), and Multivariate Adaptive Regression Splines implemented in MaxEnt software. Model validation statistics [Area Under the Curve (AUC), True Skill Statistics (TSS)], and Kappa index were used to evaluate the accuracy of each model. Models with a TSS above 0.65 were used to prepare an ensemble model. The results showed that among the different climate variables, precipitation and temperature (Bio18, Bio7, Bio8, and bio9) in the case of O. persica and similarly, gsl (growing season length TREELIM, highlighting the warming climate and the endophytic/pathogenic nature of the fungus) and precipitation in case of B. mediterranea are the most important influencing variables in disease modeling, while near-surface wind speed (sfcwind) is the least important variant. The RF algorithm generates the most robust predictions (ROC of 0.95; TSS of 0.77 and 0.79 for MP and OP, respectively). Theoretical analysis shows that the ensemble model (ROC of 0.95 and 0.96; TSS = 0.79 and 0.81 for MP and OP, respectively), can efficiently be used in the prediction of the charcoal disease spatiotemporal distribution. The oak mortality varied ranging from 2 to 14%. Wood-boring beetles association with diseased trees was determined at 20%. Results showed that water deficiency is a crucial component of the oak decline phenomenon in Iran. The Northern Zagros forests (Ilam, Lorestan, and Kermanshah provinces) along with the southern Zagros forests (Fars and Kohgilouyeh va-Boyer Ahmad provinces) among others are the most endangered areas of potential future pandemics of charcoal disease. Our findings will significantly improve our understanding of the current situation of the disease to pave the way against pathogenic agents in Iran.


Assuntos
Ascomicetos , Quercus , Quercus/microbiologia , Carvão Vegetal , Irã (Geográfico)/epidemiologia
2.
BMC Genomics ; 25(1): 328, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38566015

RESUMO

BACKGROUND: Whole-genome duplication and long terminal repeat retrotransposons (LTR-RTs) amplification in organisms are essential factors that affect speciation, local adaptation, and diversification of organisms. Understanding the karyotype projection and LTR-RTs amplification could contribute to untangling evolutionary history. This study compared the karyotype and LTR-RTs evolution in the genomes of eight oaks, a dominant lineage in Northern Hemisphere forests. RESULTS: Karyotype projections showed that chromosomal evolution was relatively conservative in oaks, especially on chromosomes 1 and 7. Modern oak chromosomes formed through multiple fusions, fissions, and rearrangements after an ancestral triplication event. Species-specific chromosomal rearrangements revealed fragments preserved through natural selection and adaptive evolution. A total of 441,449 full-length LTR-RTs were identified from eight oak genomes, and the number of LTR-RTs for oaks from section Cyclobalanopsis was larger than in other sections. Recent amplification of the species-specific LTR-RTs lineages resulted in significant variation in the abundance and composition of LTR-RTs among oaks. The LTR-RTs insertion suppresses gene expression, and the suppressed intensity in gene regions was larger than in promoter regions. Some centromere and rearrangement regions indicated high-density peaks of LTR/Copia and LTR/Gypsy. Different centromeric regional repeat units (32, 78, 79 bp) were detected on different Q. glauca chromosomes. CONCLUSION: Chromosome fusions and arm exchanges contribute to the formation of oak karyotypes. The composition and abundance of LTR-RTs are affected by its recent amplification. LTR-RTs random retrotransposition suppresses gene expression and is enriched in centromere and chromosomal rearrangement regions. This study provides novel insights into the evolutionary history of oak karyotypes and the organization, amplification, and function of LTR-RTs.


Assuntos
Quercus , Retroelementos , Quercus/genética , Genoma de Planta , Cariótipo , Sequências Repetidas Terminais/genética , Evolução Molecular , Filogenia
3.
Sci Rep ; 14(1): 5457, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443433

RESUMO

The effects of boiling water treatment on the physical properties of Quercus variabilis virgin cork (Qv VC) were examined and compared with those of Quercus suber reproduction cork (Qs RC). The water treatment was conducted at 100 °C for 1 h. Qv VC showed a significantly higher dimensional change in the three directions and lower weight loss than Qs RC by boiling water treatment. Untreated and boiled Qv VC showed higher density, air-dried moisture content, red/green (a*) and yellow/blue (b*) chromaticity, overall color change, shrinkage in all three directions, moisture adsorption on the entire surface, and swelling per 1% moisture content than untreated and boiled Qs RC. However, the lightness (L*) and water absorption on each surface were higher for Qs RC than for Qv VC. Moisture adsorption on each surface was comparable before and after heat treatment for both species. After boiling water treatment, the air-dried moisture content, dimensions, volume shrinkage, water absorption, and moisture adsorption on each surface and the entire surface increased, whereas L*, a*, b*, and swelling per 1% moisture content decreased. The results of the present study could be useful for further utilization of Qv cork growing in Korea.


Assuntos
Hipertermia Induzida , Quercus , Fenômenos Físicos , Adsorção , Fatores de Transcrição , Água , República da Coreia
4.
PLoS One ; 19(3): e0299645, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38478564

RESUMO

Monodominant tree communities can have phenotypic trait variation (intraspecific variation) as extreme as the trait variation across a forest with higher species diversity. An example of such forests is those composed of Quercus, an important genus of woody angiosperms in the montane neotropical forest. The Andean oak, or Quercus humboldtii Bonpl., is the sole member of this genus in South America and a characteristic component of montane ecosystems. Although there are several studies on the ecology and genetic structure of this species, there are few studies on the functional trait diversity among populations. Understanding functional traits can improve our comprehension of how organisms respond to various environmental conditions. In this study, we aimed to evaluate differences in six functional traits in individuals of the Andean oak, in two ontogenetic stages (juveniles and adults) from three populations with contrasting environmental conditions. Additionally, using T-statistics, we assessed the impact of external filters (e.g., climate, resource availability, large-scale biotic interactions) on population assembly. We found a remarkable level of functional differentiation among Andean oak forests, with all traits differing between populations and five traits differing between ontogenetic stages. External filters had a stronger influence in populations with more extreme environmental conditions. These findings emphasize the dynamic and context-dependent nature of functional traits in this species. However, given the limited exploration of functional diversity in Andean oak populations, further studies are needed to inform conservation efforts.


Assuntos
Ecossistema , Quercus , Humanos , Quercus/genética , Florestas , Árvores , Ecologia
5.
Zootaxa ; 5418(2): 140-158, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38480366

RESUMO

The life cycle of Cerroneuroterus minutulus (Giraud, 1859), a species previously known only from its asexual generation, is closed. Our study demonstrates that C. minutulus exhibits the heterogony typical of Cynipini species, with alternating sexual and asexual generations. The identity of the sexual generation is demonstrated by laboratory experiments and confirmed by molecular data, with Cerroneuroterus aggregatus (Wachtl, 1880) determined to be the sexual generation, and junior synonym, of Cerroneuroterus minutulus (Giraud, 1859). Illustrations and diagnoses for adults and galls, observations on biology and distribution information are provided as is a detailed redescription of the sexual generation of C. minutulus.


Assuntos
Himenópteros , Quercus , Vespas , Animais , Estágios do Ciclo de Vida
6.
Zootaxa ; 5403(3): 369-376, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38480432

RESUMO

A new species of oak gall wasp, Andricus coombesi Pujade-Villar & Prez-Torres n. sp. from Mexico, known only from its asexual generation that induces galls on acorns of Quercus grahamii Benth., (section Lobatae) is described. Its presence causes the complete disappearance of the acorn. Diagnosis, distribution and biological data of the new species are given. Andricus coombesi Pujade-Villar & Prez-Torres n. sp. represents the first gall wasp species mentioned from this host.


Assuntos
Himenópteros , Quercus , Vespas , Animais
7.
Ying Yong Sheng Tai Xue Bao ; 35(2): 298-306, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38523086

RESUMO

Based on the continuous inventory data of forest resources in Zhejiang Province in 2019 and 2021, we used statistical methods such as polynomial regression to analyze the impacts of topography and forest spatial structure on average annual diameter at breast height (DBH) growth of main pioneer tree species in natural broad-leaved mixed forests. The results showed that DBH of Schima superba, Quercus glauca, Quercus fabri, Lithocarpus glaber, Castanopsis eyrei, and Castanopsis sclerophylla were between 5-50.8, 5-41.5, 5-50.8, 5-43.9, 5-55.5, and 5-46.1 cm, respectively. We classified all the trees into three classes based on DBH: small (6-12 cm), medium (12-14 cm), and large (>26 cm). The average annual DBH growth of S. superba and Q. glauca was the highest on semi-shady slope and shady slope, with increases of 2.9%-15.7% and 1.1%-41.2%, respectively. The average annual DBH growth of large-diameter S. superba, L. glaber, C. eyrei and C. sclerophylla decreased with the increase of slope, with a maximum decrease of 27.0% for S. superba, with no significant difference among small- and medium-diameter trees as a whole. The slope position did not affect the annual DBH growth of small-diameter trees, while that of medium- and large-diameter S. superba, Q. glauca, and large-diameter Q. fabri, L. glaber decreased with the change of slope position from downhill, mesoslope, uphill to ridge, with a maximum decrease of 28.1% for L. glabe, and the major-diameter C. eyrei was on the contrary. Appropriate increase in the mingling was beneficial to the average annual DBH growth of medium- and large-diameter trees. Moderate mixing was suitable for S. superba, while low degree mixing and moderate mixing was suitable for Q. glauca, Q. fabri and L. glaber, and intensive mixing was suitable for C. eyrei and C. sclerophylla. No significant difference was observed for minor-diameter trees under the mingling. The neighborhood comparison only had a significant effect on the average annual DBH growth of large-diameter Q. glauca, Q. fabri, and L. glaber, which was significantly higher under subdominance-moderation than moderation-inferiority. The average annual DBH growth in the study area was mainly affected by aspect and mixing degree.


Assuntos
Pinus , Quercus , Árvores , Florestas , China
8.
Ying Yong Sheng Tai Xue Bao ; 35(2): 347-353, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38523091

RESUMO

In recent years, PM2.5 pollution has become a most important source of air pollution. Prolonged exposure to high PM2.5 concentrations can give rise to severe health issues. Negative air ion (NAI) is an important indicator for measuring air quality, which is collectively known as the 'air vitamin'. However, the intricate and fluctuating meteorological conditions and vegetation types result in numerous uncertainties in the correlation between PM2.5 and NAI. In this study, we collected data on NAI, PM2.5, and meteorological elements through positioning observation during the period of June to September in 2019 and 2020 under the condition of relatively constant leaf area in Quercus variabilis forest, a typical forest in warm temperate zones. We investigated the spatiotemporal variation of PM2.5 and NAI under consistent meteorological conditions, established the correlation between PM2.5 and NAI, and explicated the impact mechanism of PM2.5 on NAI in natural conditions. The results showed that NAI decreased exponentially with the increases in natural PM2.5, with a significant negative correlation (y=1148.79x-0.123). The decrease rates of NAI in PM2.5 concentrations of 0-20, 20-40, 40-80, 80-100 and 100-120 µg·m-3 were 40.1%, 36.2%, 9.4%, 2.4%, 5.1% and 6.8%, respectively. Results of the sensitivity analysis showed that the PM2.5 concentration range of 0-40 µg·m-3 was the sensitive range that affected NAI. Our findings could provide a scientific basis for better understanding the response mechanisms of NAI to environmental factors.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Quercus , Poluentes Atmosféricos/análise , Material Particulado/análise , Poluição do Ar/análise , Florestas , Monitoramento Ambiental/métodos , China
9.
Mycorrhiza ; 34(1-2): 45-55, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38483629

RESUMO

Worldwide urban landscapes are expanding because of the growing human population. Urban ecosystems serve as habitats to highly diverse communities. However, studies focusing on the diversity and structure of ectomycorrhizal communities are uncommon in this habitat. In Colombia, Quercus humboldtii Bonpl. is an ectomycorrhizal tree thriving in tropical montane forests hosting a high diversity of ectomycorrhizal fungi. Q. humboldtii is planted as an urban tree in Bogotá (Colombia). We studied how root-associated fungal communities of this tree change between natural and urban areas. Using Illumina sequencing, we amplified the ITS1 region and analyzed the resulting data using both OTUs and Amplicon Sequence Variants (ASVs) bioinformatics pipelines. The results obtained using both pipelines showed no substantial differences between OTUs and ASVs for the community patterns of root-associated fungi, and only differences in species richness were observed. We found no significant differences in the species richness between urban and rural sites based on Fisher's alpha or species-accumulation curves. However, we found significant differences in the community composition of fungi present in the roots of rural and urban trees with rural communities being dominated by Russula and Lactarius and urban communities by Scleroderma, Hydnangium, and Trechispora, suggesting a high impact of urban disturbances on ectomycorrhizal fungal communities. Our results highlight the importance of urban trees as reservoirs of fungal diversity and the potential impact of urban conditions on favoring fungal species adapted to more disturbed ecosystems.


Assuntos
Agaricales , Basidiomycota , Micobioma , Micorrizas , Quercus , Humanos , Micorrizas/genética , Ecossistema , Quercus/microbiologia , Biodiversidade , DNA Fúngico/genética , Árvores/microbiologia
10.
Environ Pollut ; 347: 123699, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38460588

RESUMO

As global air pollution, particularly fine particulate matter (PM2.5), has become a major environmental problem, various PM2.5 mitigation technologies including green infrastructure have received significant attention. However, owing to spatial constraints on urban greening, there is a lack of management plans for urban forests to efficiently mitigate PM2.5. In this study, we assessed the PM2.5 reduction capabilities of Pinus densiflora (Korean red pine) and Quercus acutissima (sawtooth oak) by measuring the changes of PM2.5 concentrations using an experimental chamber system. In addition, the PM2.5 reduction efficiency in 90 min (PMRE90) and the amount of PM2.5 reduction per leaf area (PMRLA) were compared based on arrangement structures and density levels. The results showed that the PM2.5 reduction by plants was significantly greater than that of the control experiment without any plants, and an additional reduction effect of approximately 1.38 times was induced by a 1.5 m s-1 air flow. The PMRE90 of Korean red pine was the highest at medium density. In contrast, the PMRE90 of sawtooth oak was the highest at high density. The PMRLA of both species was highest at low densities. The different responses of the species to total reduction were well explained by total leaf area (TLA). The PMRE90 of both species was positively correlated with TLA. The PMRLA of sawtooth oak was approximately 2.3 times greater than that of Korean red pine. However, there were no significant differences in both PMRE90 and PMRLA between the arrangement structures. Our findings reveal the potential mechanisms of vegetation in reducing PM2.5 according to arrangement structure and density. This highlights the importance of efficiently using urban green spaces with spatial constraints on PM2.5 mitigation in the future.


Assuntos
Poluentes Atmosféricos , Pinus , Quercus , Árvores/química , Material Particulado/análise , República da Coreia , Poluentes Atmosféricos/análise
11.
BMC Plant Biol ; 24(1): 168, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438905

RESUMO

BACKGROUND: Forests are essential for maintaining species diversity, stabilizing local and global climate, and providing ecosystem services. Exploring the impact of paleogeographic events and climate change on the genetic structure and distribution dynamics of forest keystone species could help predict responses to future climate change. In this study, we combined an ensemble species distribution model (eSDM) and multilocus phylogeography to investigate the spatial genetic patterns and distribution change of Quercus glauca Thunb, a keystone of East Asian subtropical evergreen broad-leaved forest. RESULTS: A total of 781 samples were collected from 77 populations, largely covering the natural distribution of Q. glauca. The eSDM showed that the suitable habitat experienced a significant expansion after the last glacial maximum (LGM) but will recede in the future under a general climate warming scenario. The distribution centroid will migrate toward the northeast as the climate warms. Using nuclear SSR data, two distinct lineages split between east and west were detected. Within-group genetic differentiation was higher in the West than in the East. Based on the identified 58 haplotypes, no clear phylogeographic structure was found. Populations in the Nanling Mountains, Wuyi Mountains, and the southwest region were found to have high genetic diversity. CONCLUSIONS: A significant negative correlation between habitat stability and heterozygosity might be explained by the mixing of different lineages in the expansion region after LGM and/or hybridization between Q. glauca and closely related species. The Nanling Mountains may be important for organisms as a dispersal corridor in the west-east direction and as a refugium during the glacial period. This study provided new insights into spatial genetic patterns and distribution dynamics of Q. glauca.


Assuntos
Ecossistema , Quercus , Quercus/genética , Filogeografia , Florestas , Mudança Climática
12.
J Hered ; 115(2): 221-229, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38305464

RESUMO

Island oak (Quercus tomentella) is a rare relictual island tree species that exists only on six islands off the coast of California and Mexico, but was once widespread throughout mainland California. Currently, this species is endangered by threats such as non-native plants, grazing animals, and human removal. Efforts for conservation and restoration of island oak currently underway could benefit from information about its range-wide genetic structure and evolutionary history. Here we present a high-quality genome assembly for Q. tomentella, assembled using PacBio HiFi and Omni-C sequencing, developed as part of the California Conservation Genomics Project (CCGP). The resulting assembly has a length of 781 Mb, with a contig N50 of 22.0 Mb and a scaffold N50 of 63.4 Mb. This genome assembly will provide a resource for genomics-informed conservation of this rare oak species. Additionally, this reference genome will be the first one available for a species in Quercus section Protobalanus, a unique oak clade present only in western North America.


Assuntos
Quercus , Árvores , Animais , Humanos , Árvores/genética , Genômica , México , América do Norte
13.
Ultrason Sonochem ; 104: 106826, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38422810

RESUMO

Ageing wine in barrels is an historical practice used to improve the aromatic complexity of wine, but due to the high cost and the long ageing period, alternative approaches have been developed, such as the use of wood chips and ultrasound treatment. The present paper reports the results of an investigation performed on wine (cv. Primitivo). Three treatments were investigated: a) control wine untreated; b) wine with toasted vine-shoot chips (10 g/L); c) wine with toasted vine-shoot chips (10 g/L) and treated by ultrasound. Wines were analysed after 7, 14, 21, and 28 days. The application of ultrasound combined with vine-shoot chips promoted tannin evolution, thereby accelerating the ageing process of wine. The chips addition decreased the total anthocyanins content and increased the stilbenes (trans-resveratrol and trans-piceid) and wood-related aromas (i.e., furfural, 5-methylfurfural) concentration. Finally, wines added with chips were richer in woody, vanilla, oak, and chocolate notes and more preferred by the tasters.


Assuntos
Quercus , Vinho , Vinho/análise , Antocianinas/análise , Resveratrol/análise , Madeira/química
14.
Genes (Basel) ; 15(2)2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38397219

RESUMO

Quercus is a valuable genus ecologically, economically, and culturally. They are keystone species in many ecosystems. Species delimitation and phylogenetic studies of this genus are difficult owing to frequent hybridization. With an increasing number of genetic resources, we will gain a deeper understanding of this genus. In the present study, we collected four Quercus section Cyclobalanopsis species (Q. poilanei, Q. helferiana, Q. camusiae, and Q. semiserrata) distributed in Southeast Asia and sequenced their complete genomes. Following analysis, we compared the results with those of other species in the genus Quercus. These four chloroplast genomes ranged from 160,784 bp (Q. poilanei) to 161,632 bp (Q. camusiae) in length, with an overall guanine and cytosine (GC) content of 36.9%. Their chloroplast genomic organization and order, as well as their GC content, were similar to those of other Quercus species. We identified seven regions with relatively high variability (rps16, ndhk, accD, ycf1, psbZ-trnG-GCC, rbcL-accD, and rpl32-trnL-UAG) which could potentially serve as plastid markers for further taxonomic and phylogenetic studies within Quercus. Our phylogenetic tree supported the idea that the genus Quercus forms two well-differentiated lineages (corresponding to the subgenera Quercus and Cerris). Of the three sections in the subgenus Cerris, the section Ilex was split into two clusters, each nested in the other two sections. Moreover, Q. camusiae and Q. semiserrata detected in this study diverged first in the section Cyclobalanopsis and mixed with Q. engleriana in the section Ilex. In particular, 11 protein coding genes (atpF, ndhA, ndhD, ndhF, ndhK, petB, petD, rbcL, rpl22, ycf1, and ycf3) were subjected to positive selection pressure. Overall, this study enriches the chloroplast genome resources of Quercus, which will facilitate further analyses of phylogenetic relationships in this ecologically important tree genus.


Assuntos
Genoma de Cloroplastos , Quercus , Filogenia , Quercus/genética , Ecossistema , Genômica
15.
Biomolecules ; 14(2)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38397397

RESUMO

Holm oak (Quercus ilex) is considered to be one of the major structural elements of Mediterranean forests and the agrosilvopastoral Spanish "dehesa", making it an outstanding example of ecological and socioeconomic sustainability in forest ecosystems. The exotic Phytophthora cinnamomi is one of the most aggressive pathogens of woody species and, together with drought, is considered to be one of the main drivers of holm oak decline. The effect of and response to P. cinnamomi inoculation were studied in the offspring of mother trees from two Andalusian populations, Cordoba and Huelva. At the two locations, acorns collected from both symptomatic (damaged) and asymptomatic (apparently healthy) trees were sampled. Damage symptoms, mortality, and chlorophyll fluorescence were evaluated in seedlings inoculated under humid and drought conditions. The effect and response depended on the population and were more apparent in Huelva than in Cordoba. An integrated proteomic and metabolomic analysis revealed the involvement of different metabolic pathways in response to the pathogen in both populations, including amino acid metabolism pathways in Huelva, and terpenoid and flavonoid biosynthesis in Cordoba. However, no differential response was observed between seedlings inoculated under humid and drought conditions. A protective mechanism of the photosynthetic apparatus was activated in response to defective photosynthetic activity in inoculated plants, which seemed to be more efficient in the Cordoba population. In addition, enzymes and metabolites of the phenylpropanoid and flavonoid biosynthesis pathways may have conferred higher resistance in the Cordoba population. Some enzymes are proposed as markers of resilience, among which glyoxalase I, glutathione reductase, thioredoxin reductase, and cinnamyl alcohol dehydrogenase are candidates.


Assuntos
Phytophthora , Quercus , Ecossistema , Secas , Proteômica , Árvores , Plântula , Flavonoides/metabolismo
16.
Sci Total Environ ; 919: 170681, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38325486

RESUMO

Plant functional attributes are subjected to environmental adjustments, which lead to modulations in forest processes under environmental changes. However, a comprehensive assessment of the relationships between plant traits and carbon stock remains subtle. The present study attempted to accomplish the gap of knowledge by examining the linkages between forest carbon with plant traits within the Banj Oak forest in the Garhwal Himalaya. Twelve individuals from three major species in the Banj Oak forest were randomly selected for trait measurements, and soil samples were collected randomly across the area for evaluation of soil nutrients and carbon. Forest biomass and soil carbon were estimated following standard protocols. A Structural Equation Model (SEM) was applied to establish the relationship between above ground carbon (AGC) and soil organic carbon (SOC) with leaf and stem traits, and soil nutrients. Stem traits were tree height and tree diameter; whereas leaf morphological traits were leaf area, specific leaf area, leaf dry matter content; leaf physiological traits were photosynthesis rate, stomatal conductance, and transpiration rate; and leaf biochemical traits were leaf carbon concentration, leaf nitrogen concentration, and leaf phosphorus concentration. Soil nutrients were available nitrogen, available phosphorus, and exchangeable potassium. Based on SEM results, AGC of the forest was positively correlated with stem traits and leaf physiological traits, while negatively correlated with leaf morphological traits. SOC was positively correlated with soil nutrients and leaf biochemical traits, whereas negatively correlated with stem traits. These findings may support for precise quantification of forest carbon and modeling of forest carbon stocks besides providing inputs to forest managers for devising effective forest management strategies.


Assuntos
Carbono , Quercus , Humanos , Sequestro de Carbono , Solo/química , Florestas , Árvores/fisiologia , Nitrogênio/análise , Fósforo , Folhas de Planta/química
17.
Sci Total Environ ; 918: 170531, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38309368

RESUMO

Coppicing is one of the oldest silvicultural practices and is still widely applied to produce renewable energy from broadleaf forests. However, the consequences on microclimate and understorey vegetation are still poorly understood, especially in Mediterranean oak forests. With the ongoing changes in the climate system and global biodiversity loss, a better understanding of how the forest temperature buffering capacity and below-canopy plant community are impacted by coppicing is crucial. Here we quantify microclimate and understorey vegetation changes in adjacent ancient coppice-with-standards and high forest stands dominated by oaks in Italy, where these systems have been applied for a long time. Air and soil temperatures were recorded for 2.5 years, and nested vegetation plots were used to analyse coppicing effects on species composition, taxonomic, phylogenetic, and functional diversity. Coppicing significantly reduced the forest temperature buffering capacity. The mean of the daily maximum temperatures over the entire period was 1.45 °C higher in the coppiced sites, whereas the mean of the daily minimum temperatures was 0.62 °C lower than in the high forest. Coppicing increased understorey species richness by favouring generalist taxa, but significantly decreased the proportion of forest specialists. The understorey community in coppiced forests consisted of more warm-adapted species. Moreover, coppicing also led to a loss of phylogenetic evenness and to shifts in diversity and community weighted mean Leaf Dry Matter content, pointing to habitat filtering and acclimation processes. In sum, we show that coppicing affects microclimate and understory vegetation in a direction that can exacerbate the effects of climate change, negatively affecting the oak forest specialist flora and its phylogenetic evenness.


Assuntos
Quercus , Microclima , Filogenia , Florestas , Ecossistema , Biodiversidade
18.
Oecologia ; 204(3): 529-542, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38324065

RESUMO

Understanding the drivers of trade-offs among traits is vital for comprehending the evolution and maintenance of trait variation. Theoretical frameworks propose that evolutionary mechanisms governing trade-offs frequently exhibit a scale-dependent nature. However, empirical tests of whether trade-offs exhibited across various biological scales (i.e. individuals, populations, species, genera, etc.) remains scarce. In this study, we explore trade-off between dispersal and reproductive effort among sympatric sister species of wasps in the genus Belonocnema (Hymenoptera: Cynipini: Cynipidae) that form galls on live oaks: B. fossoria, which specializes on Quercus geminata, and B. treatae, which specializes on Q. virginiana. Specifically, our results suggest that B. fossoria has evolved reduced flight capability and smaller wings, but a larger abdomen and greater total reproductive effort than B. treatae, which has larger wings and is a stronger flier, but has a smaller abdomen and reduced total reproductive effort. These traits and the relationships among them remain unchanged when B. fossoria and B. treatae are transplanted and reared onto the alternative host plant, suggesting that trait divergence is genetically based as opposed to being a plastic response to the different rearing environments. However, when looking within species, we found no evidence of intraspecific trade-offs between wing length and reproductive traits within either B. fossoria or B. treatae. Overall, our results indicate that observed trade-offs in life history traits between the two gall former species are likely a result of independent adaptations in response to different environments as opposed to the amplified expression of within species intrinsic tradeoffs.


Assuntos
Quercus , Vespas , Humanos , Animais , Herbivoria , Reprodução , Vespas/fisiologia , Plantas
19.
Environ Monit Assess ; 196(3): 287, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38378878

RESUMO

Soil respiration (RS) is one of the largest terrestrial sources of CO2 causing global warming and may vary according to land use and vegetation type. Türkiye is in the first place in the world in terms of area of hazelnut orchards that are generally converted from natural forests. The aim of this study was the comparison of the effects of cultural practices (pruning, fertilizing, and pruning+fertilizing) on RS in hazelnut orchards and that of the adjacent natural oak forest. Every trial site had a statistically similar annual mean RS, which ranged from 0.15 to 1.55 g C m-2 day-1. The RS on the sites was different only in the spring season and was similar in the other seasons. The RS of the pruned and fertilized hazelnut orchard (Hpf) in the spring was 58% greater than the unmaintained hazelnut orchard (Hc) and oak forest and 28% greater than the only fertilized hazelnut orchard (Hf). The RS of Hpf was also greater than other sites in most monthly measurements. While the positive correlation between soil moisture and RS was on an annual basis (r = 0.44), it was higher in summer (r = 0.61) and autumn (r = 0.55) seasons. The negative correlation between soil temperature and RS in the summer and autumn seasons evolved positively in winter. The results of the study suggest that the maintenance practices applied in the hazelnut garden could increase RS in the spring when soil moisture and temperature are optimal but have no effect in other seasons or on an annual basis.


Assuntos
Corylus , Quercus , Solo , Monitoramento Ambiental , Florestas , Temperatura , Respiração , Estações do Ano , China , Dióxido de Carbono/análise
20.
Environ Monit Assess ; 196(3): 289, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38381166

RESUMO

The current research is conducted to model the effect of climate change and land use change (LUC) on the geographical distribution of Quercus brantii Lindl. (QB) forests across their historical range. Forecasting was done based on six general circulation models under RCP 2.6 and RCP 8.5 future climate change scenarios for the future years 2050 and 2070. In order to model the species distribution, different modeling methods were used. The results indicated that, in general, climatic variables had a higher influence on the distribution of QB than land use-related attributes. The mean diurnal range (bio2), the precipitation seasonality (bio15), and the mean temperature of the driest quarter (bio9) were the main predictors in the distribution of QB forests, while land use variables were less important in oak species distribution. The GBM, MaxEnt, and RF had higher accuracy and performance in modeling species distribution. The outputs also showed that in the current climate circumstances, 97,608.81 km2 of the studied area has high desirability for the presence of QB, and by 2070, under the pessimistic scenario, 96.29% of these habitats will be lost under the concomitant effect of LUC and climate change. By using the results of this research, it is possible to predict and identify the effective factors in changing the habitat of this oak species with more certainty. Based on the insights obtained from the results of such studies, the protection and restoration planning of the habitat of this key species, which supports diverse species, will be provided more efficiently.


Assuntos
Quercus , Monitoramento Ambiental , Florestas , Mudança Climática , Dessecação
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