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981.
982.
Bao G. Z. Tang W. Y. Zhou S. J. Liu B. J. Wu Z. Z. Jin D. X. Bian W. J. Zhu S. N. 《Russian Journal of Plant Physiology》2020,67(3):529-537
Russian Journal of Plant Physiology - To explore the physiological response characteristics of plant photosynthesis under acid precipitation stress (A stress), snow-melting agent stress (S stress),... 相似文献
983.
Guo Y. Y. Li H. J. Zhao C. F. Xue J. Q. Zhang R. H. 《Russian Journal of Plant Physiology》2020,67(5):809-821
Russian Journal of Plant Physiology - Melatonin is known to exert protective effects in maize against drought stress, but the knowledge regarding interaction among the melatonin, photosynthetic... 相似文献
984.
Guo Y. Y. Li H. J. Liu J. Bai Y. W. Xue J. Q. Zhang R. H. 《Russian Journal of Plant Physiology》2020,67(2):312-322
Russian Journal of Plant Physiology - Melatonin plays an important role in the enhancement of plant tolerance to drought stress. The underlying mechanisms of this melatonin-induced protection of... 相似文献
985.
Jiangong Liu Yulun Zhou Alex Valach Robert Shortt Kuno Kasak Camilo Rey‐Sanchez Kyle S. Hemes Dennis Baldocchi Derrick Y. F. Lai 《Global Change Biology》2020,26(9):4998-5016
The role of coastal mangrove wetlands in sequestering atmospheric carbon dioxide (CO2) and mitigating climate change has received increasing attention in recent years. While recent studies have shown that methane (CH4) emissions can potentially offset the carbon burial rates in low‐salinity coastal wetlands, there is hitherto a paucity of direct and year‐round measurements of ecosystem‐scale CH4 flux (FCH4) from mangrove ecosystems. In this study, we examined the temporal variations and biophysical drivers of ecosystem‐scale FCH4 in a subtropical estuarine mangrove wetland based on 3 years of eddy covariance measurements. Our results showed that daily mangrove FCH4 reached a peak of over 0.1 g CH4‐C m?2 day?1 during the summertime owing to a combination of high temperature and low salinity, while the wintertime FCH4 was negligible. In this mangrove, the mean annual CH4 emission was 11.7 ± 0.4 g CH4‐C m–2 year?1 while the annual net ecosystem CO2 exchange ranged between ?891 and ?690 g CO2‐C m?2 year?1, indicating a net cooling effect on climate over decadal to centurial timescales. Meanwhile, we showed that mangrove FCH4 could offset the negative radiative forcing caused by CO2 uptake by 52% and 24% over a time horizon of 20 and 100 years, respectively, based on the corresponding sustained‐flux global warming potentials. Moreover, we found that 87% and 69% of the total variance of daily FCH4 could be explained by the random forest machine learning algorithm and traditional linear regression model, respectively, with soil temperature and salinity being the most dominant controls. This study was the first of its kind to characterize ecosystem‐scale FCH4 in a mangrove wetland with long‐term eddy covariance measurements. Our findings implied that future environmental changes such as climate warming and increasing river discharge might increase CH4 emissions and hence reduce the net radiative cooling effect of estuarine mangrove forests. 相似文献
986.
Fire affects the taxonomic and functional composition of soil microbial communities,with cascading effects on grassland ecosystem functioning 总被引:1,自引:0,他引:1
Sihang Yang Qiaoshu Zheng Yunfeng Yang Mengting Yuan Xingyu Ma Nona R. Chiariello Kathryn M. Docherty Christopher B. Field Jessica L. M. Gutknecht Bruce A. Hungate Audrey Niboyet Xavier Le Roux Jizhong Zhou 《Global Change Biology》2020,26(2):431-442
Fire is a crucial event regulating the structure and functioning of many ecosystems. Yet few studies have focused on how fire affects taxonomic and functional diversities of soil microbial communities, along with changes in plant communities and soil carbon (C) and nitrogen (N) dynamics. Here, we analyze these effects in a grassland ecosystem 9 months after an experimental fire at the Jasper Ridge Global Change Experiment site in California, USA. Fire altered soil microbial communities considerably, with community assembly process analysis showing that environmental selection pressure was higher in burned sites. However, a small subset of highly connected taxa was able to withstand the disturbance. In addition, fire decreased the relative abundances of most functional genes associated with C degradation and N cycling, implicating a slowdown of microbial processes linked to soil C and N dynamics. In contrast, fire stimulated above‐ and belowground plant growth, likely enhancing plant–microbe competition for soil inorganic N, which was reduced by a factor of about 2. To synthesize those findings, we performed structural equation modeling, which showed that plants but not microbial communities were responsible for significantly higher soil respiration rates in burned sites. Together, our results demonstrate that fire ‘reboots’ the grassland ecosystem by differentially regulating plant and soil microbial communities, leading to significant changes in soil C and N dynamics. 相似文献
987.
Zhenhong Hu Han Y. H. Chen Chao Yue Xiao Ying Gong Junjiong Shao Guiyao Zhou Jiawei Wang Minhuang Wang Jianyang Xia Yongtao Li Xuhui Zhou Sean T. Michaletz 《Global Change Biology》2020,26(6):3429-3442
CO2 fluxes from wood decomposition represent an important source of carbon from forest ecosystems to the atmosphere, which are determined by both wood traits and climate influencing the metabolic rates of decomposers. Previous studies have quantified the effects of moisture and temperature on wood decomposition, but these effects were not separated from the potential influence of wood traits. Indeed, it is not well understood how traits and climate interact to influence wood CO2 fluxes. Here, we examined the responses of CO2 fluxes from dead wood with different traits (angiosperm and gymnosperm) to 0%, 35%, and 70% rainfall reduction across seasonal temperature gradients. Our results showed that drought significantly decreased wood CO2 fluxes, but its effects varied with both taxonomical group and drought intensity. Drought‐induced reduction in wood CO2 fluxes was larger in angiosperms than gymnosperms for the 35% rainfall reduction treatment, but there was no significant difference between these groups for the 70% reduction treatment. This is because wood nitrogen density and carbon quality were significantly higher in angiosperms than gymnosperms, yielding a higher moisture sensitivity of wood decomposition. These findings were demonstrated by a significant positive interaction effect between wood nitrogen and moisture on CO2 fluxes in a structural equation model. Additionally, we ascertained that a constant temperature sensitivity of CO2 fluxes was independent of wood traits and consistent with previous estimates for extracellular enzyme kinetics. Our results highlight the key role of wood traits in regulating drought responses of wood carbon fluxes. Given that both climate and forest management might extensively modify taxonomic compositions in the future, it is critical for carbon cycle models to account for such interactions between wood traits and climate in driving dynamics of wood decomposition. 相似文献
988.
Zhengyun Zou Qiuxiang Ou Yu Ren Qing Lv Lanqun Qin Lianjun Zhao Shu Su Xue Wu Hua Bao Ao Wang Dongqin Zhu Xiaonan Wang Yang W. Shao Baorui Liu 《Pigment cell & melanoma research》2020,33(4):601-611
The incidence of melanoma is rising globally including China. Comparing to Caucasians, the incidence of non‐cutaneous melanomas is significantly higher in Chinese. Herein, we performed genomic profiling of 89 Chinese surgically resected primary melanomas, including acral (n = 54), cutaneous (n = 22), and mucosal (n = 13), by hybrid capture‐based next‐generation sequencing. We show that mucosal melanomas tended to harbor more pathogenic mutations than other types of melanoma, though the biological significance of this finding remains uncertain. Chromosomal arm‐level alterations including 6q, 9p, and 10p/q loss were highly recurrent in all subtypes, but mucosal melanoma was significantly associated with increased genomic instability. Importantly, 7p gain significantly correlated with unfavorable clinical outcomes in non‐cutaneous melanomas, representing an intriguing prognostic biomarker of those subtypes. Furthermore, focal amplification of 4q12 (KIT, KDR, and PDGFRα) and RAD51 deletion were more abundant in mucosal melanoma, while NOTCH2 amplification was enriched in acral melanoma. Additionally, cutaneous melanomas had higher mutation load than acral melanomas, while mucosal melanomas did not differ from other subtypes in mutation burden. Together, our data revealed important features of acral and mucosal melanomas in Chinese including distinctive driver mutation pattern and increased genomic instability. These findings highlight the possibilities of combination therapies in the clinical management of melanoma. 相似文献
989.
Jia Zhou Tiffanie Maree Nelson Carlos Rodriguez Lopez Roshmi Rekha Sarma Shao Jia Zhou Lee Ann Rollins 《Molecular ecology resources》2020,20(4):844-855
Noninvasive sampling methods for studying intestinal microbiomes are widely applied in studies of endangered species and in those conducting temporal monitoring during manipulative experiments. Although existing studies show that noninvasive sampling methods among different taxa vary in their accuracy, no studies have yet been published comparing nonlethal sampling methods in adult amphibians. In this study, we compare microbiomes from two noninvasive sample types (faeces and cloacal swabs) to that of the large intestine in adult cane toads, Rhinella marina. We use 16S rRNA gene sequencing to investigate how microbial communities change along the digestive tract and which nonlethal sampling method better represents large intestinal microbiota. We found that cane toads' intestinal microbiota was dominated by Bacteroidetes, Proteobacteria and Firmicutes and, interestingly, we also saw a high proportion of Fusobacteria, which has previously been associated with marine species and changes in frog immunity. The large and small intestine of cane toads had a similar microbial composition, but the large intestine showed higher diversity. Our results indicate that cloacal swabs were more similar to large intestine samples than were faecal samples, and small intestine samples were significantly different from both nonlethal sample types. Our study provides valuable information for future investigations of the cane toad gut microbiome and validates the use of cloacal swabs as a nonlethal method to study changes in the large intestine microbiome. These data provide insights for future studies requiring nonlethal sampling of amphibian gut microbiota. 相似文献
990.
Sufang Zhang Sifan Shen Jiong Peng Xin Zhou Xiangbo Kong Pingping Ren Fu Liu Lingling Han Shuai Zhan Yongping Huang Aibing Zhang Zhen Zhang 《Molecular ecology resources》2020,20(4):1023-1037
Dendrolimus spp. are important destructive pests of conifer forests, and Dendrolimus punctatus Walker (Lepidoptera; Lasiocampidae) is the most widely distributed Dendrolimus species. During periodic outbreaks, this species is said to make “fire without smoke” because large areas of pine forest can be quickly and heavily damaged. Yet, little is known about the molecular mechanisms that underlie the unique ecological characteristics of this forest insect. Here, we combined Pacific Biosciences (PacBio) RSII single‐molecule long reads and high‐throughput chromosome conformation capture (Hi‐C) genomics‐linked reads to produce a high‐quality, chromosome‐level reference genome for D. punctatus. The final assembly was 614 Mb with contig and scaffold N50 values of 1.39 and 22.15 Mb, respectively, and 96.96% of the contigs anchored onto 30 chromosomes. Based on the prediction, this genome contained 17,593 protein‐coding genes and 56.16% repetitive sequences. Phylogenetic analyses indicated that D. punctatus diverged from the common ancestor of Hyphantria cunea, Spodoptera litura and Thaumetopoea pityocampa ~ 108.91 million years ago. Many gene families that were expanded in the D. punctatus genome were significantly enriched for the xenobiotic biodegradation system, especially the cytochrome P450 gene family. This high‐quality, chromosome‐level reference genome will be a valuable resource for understanding mechanisms of D. punctatus outbreak and host resistance adaption. Because this is the first Lasiocampidae insect genome to be sequenced, it also will serve as a reference for further comparative genomics. 相似文献