Passive-warming, open-top chambers(OTCs) are widely applied for studying the effects of future climate warming on coastal wetlands. In this study, a set of six OTCs were established at a Phragmites wetland located in ...Passive-warming, open-top chambers(OTCs) are widely applied for studying the effects of future climate warming on coastal wetlands. In this study, a set of six OTCs were established at a Phragmites wetland located in the Yellow River Delta of Dongying City, China. With data collected through online transmission and in-situ sensors, the attributes and patterns of realized OTCs warming are demonstrated.The authors also quantified the preliminary influence of experimental chamber warming on plant traits.OTCs produced an elevated average air temperature of 0.8°C(relative to controls) during the growing season(June to October) of 2018, and soil temperatures actually decreased by 0.54°C at a depth of 5 cm and 0.46°C at a depth of 30 cm in the OTCs. Variations in diel patterns of warming depend greatly on the heat sources of incoming radiation in the daytime versus soil heat flux at night. Warming effects were often larger during instantaneous analyses and influenced OTCs air temperatures from-2.5°C to 8.3°C dependent on various meteorological conditions at any given time, ranging from cooling influences from vertical heat exchange and vegetation to radiation-associated warming. Night-time temperature depressions in the OTCs were due to the low turbulence inside OTCs and changes in surface soilatmosphere heat transfer. Plant shoot density, basal diameter, and biomass of Phragmites decreased by23.2%, 6.3%, and 34.0%, respectively, under experimental warming versus controls, and plant height increased by 4.3%, reflecting less carbon allocation to stem structures as plants in the OTCs experienced simultaneous wind buffering. While these passive-warming OTCs created the desired warming effects both to the atmosphere and soils, pest damages on the plant leaves and lodging within the OTCs were extensive and serious, creating the need to consider control options for these chambers and the replicated OTCs studies underway in other Chinese Phragmites marshes(Panjin and Yancheng).展开更多
Environmentally heterogeneous mountains provide opportunities for rapid diversification and speciation.The family Prunellidae(accentors)is a group of birds comprising primarily mountain specialists that have recently ...Environmentally heterogeneous mountains provide opportunities for rapid diversification and speciation.The family Prunellidae(accentors)is a group of birds comprising primarily mountain specialists that have recently radiated across the Palearctic region.This rapid diversification poses challenges to resolving their phylogeny.Herein we sequenced the complete mitogenomes and estimated the phylogeny using all 12(including 28 individuals)currently recognized species of Prunellidae.We reconstructed the mitochondrial genome phylogeny using 13 protein-coding genes of 12 species and 2 Eurasian Tree Sparrows(Passer montanus).Phylogenetic relationships were estimated using a suite of analyses:maximum likelihood,maximum parsimony and the coalescent-based SVDquartets.Divergence times were estimated by implementing a Bayesian relaxed clock model in BEAST2.Based on the BEAST time-calibrated tree,we implemented an ancestral area reconstruction using RASP v.4.3.Our phylogenies based on the maximum likelihood,maximum parsimony and SVDquartets approaches support a clade of large-sized accentors(subgenus Laiscopus)to be sister to all other accentors with small size(subgenus Prunella).In addition,the trees also support the sister relationship of P.immaculata and P.rubeculoides+P.atrogularis with 100%bootstrap support,but the relationships among the remaining eight species in the Prunella clade are poorly resolved.These species cluster in different positions in the three phylogenetic trees and the nodes are often poorly supported.The five nodes separating the seven species diverged simultaneously within less than half million years(i.e.,between 2.71 and 3.15 million years ago),suggesting that the recent radiation is likely responsible for rampant incomplete lineage sorting and gene tree conflicts.Ancestral area reconstruction indicates a central Palearctic region origin for Prunellidae.Our study highlights that whole mitochondrial genome phylogeny can resolve major lineages within Prunellidae but is not sufficient to fully resolve the relationship among the species in the Prunella clade that almost simultaneously diversify during a short time period.Our results emphasize the challenge to reconstruct reliable phylogenetic relationship in a group of recently radiated species.展开更多
基金jointly funded by the Marine S&T Fund of Shandong Province for the Pilot National Laboratory for Marine Science and Technology (Qingdao)(2022QNLM 040003-3)the National Key R&D Program of China (2016YFE0109600)+3 种基金National Natural Science Foundation of China (U22A20558, 41240022, 41876057, 40872167, 41602143)China Geological Survey (1212010611402, GZH201200503, and DD20160144)by in-kind support from the Land Carbon ProgramLand Change Science R&D Program of the United States Geological Survey。
文摘Passive-warming, open-top chambers(OTCs) are widely applied for studying the effects of future climate warming on coastal wetlands. In this study, a set of six OTCs were established at a Phragmites wetland located in the Yellow River Delta of Dongying City, China. With data collected through online transmission and in-situ sensors, the attributes and patterns of realized OTCs warming are demonstrated.The authors also quantified the preliminary influence of experimental chamber warming on plant traits.OTCs produced an elevated average air temperature of 0.8°C(relative to controls) during the growing season(June to October) of 2018, and soil temperatures actually decreased by 0.54°C at a depth of 5 cm and 0.46°C at a depth of 30 cm in the OTCs. Variations in diel patterns of warming depend greatly on the heat sources of incoming radiation in the daytime versus soil heat flux at night. Warming effects were often larger during instantaneous analyses and influenced OTCs air temperatures from-2.5°C to 8.3°C dependent on various meteorological conditions at any given time, ranging from cooling influences from vertical heat exchange and vegetation to radiation-associated warming. Night-time temperature depressions in the OTCs were due to the low turbulence inside OTCs and changes in surface soilatmosphere heat transfer. Plant shoot density, basal diameter, and biomass of Phragmites decreased by23.2%, 6.3%, and 34.0%, respectively, under experimental warming versus controls, and plant height increased by 4.3%, reflecting less carbon allocation to stem structures as plants in the OTCs experienced simultaneous wind buffering. While these passive-warming OTCs created the desired warming effects both to the atmosphere and soils, pest damages on the plant leaves and lodging within the OTCs were extensive and serious, creating the need to consider control options for these chambers and the replicated OTCs studies underway in other Chinese Phragmites marshes(Panjin and Yancheng).
基金funded by the National Natural Science Foundation of China(NSFC32020103005)the Third Xinjiang Scientific Expedition and Research(XIKK)(2022xjkk0205)Second Tibetan Plateau Scientific Expedition and Research(2019QZKK0501)。
文摘Environmentally heterogeneous mountains provide opportunities for rapid diversification and speciation.The family Prunellidae(accentors)is a group of birds comprising primarily mountain specialists that have recently radiated across the Palearctic region.This rapid diversification poses challenges to resolving their phylogeny.Herein we sequenced the complete mitogenomes and estimated the phylogeny using all 12(including 28 individuals)currently recognized species of Prunellidae.We reconstructed the mitochondrial genome phylogeny using 13 protein-coding genes of 12 species and 2 Eurasian Tree Sparrows(Passer montanus).Phylogenetic relationships were estimated using a suite of analyses:maximum likelihood,maximum parsimony and the coalescent-based SVDquartets.Divergence times were estimated by implementing a Bayesian relaxed clock model in BEAST2.Based on the BEAST time-calibrated tree,we implemented an ancestral area reconstruction using RASP v.4.3.Our phylogenies based on the maximum likelihood,maximum parsimony and SVDquartets approaches support a clade of large-sized accentors(subgenus Laiscopus)to be sister to all other accentors with small size(subgenus Prunella).In addition,the trees also support the sister relationship of P.immaculata and P.rubeculoides+P.atrogularis with 100%bootstrap support,but the relationships among the remaining eight species in the Prunella clade are poorly resolved.These species cluster in different positions in the three phylogenetic trees and the nodes are often poorly supported.The five nodes separating the seven species diverged simultaneously within less than half million years(i.e.,between 2.71 and 3.15 million years ago),suggesting that the recent radiation is likely responsible for rampant incomplete lineage sorting and gene tree conflicts.Ancestral area reconstruction indicates a central Palearctic region origin for Prunellidae.Our study highlights that whole mitochondrial genome phylogeny can resolve major lineages within Prunellidae but is not sufficient to fully resolve the relationship among the species in the Prunella clade that almost simultaneously diversify during a short time period.Our results emphasize the challenge to reconstruct reliable phylogenetic relationship in a group of recently radiated species.
