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991.
Paul Daly Mao Peng Hugh D. Mitchell Young-Mo Kim Charles Ansong Heather Brewer Peter de Gijsel Mary S. Lipton Lye Meng Markillie Carrie D. Nicora Galya Orr Ad Wiebenga Kristiina S. Hildén Mirjam A. Kabel Scott E. Baker Miia R. Mäkelä Ronald P. de Vries 《Environmental microbiology》2020,22(3):1154-1166
992.
Samuel Barton James Jenkins Angus Buckling C.-Elisa Schaum Nicholas Smirnoff John A. Raven Gabriel Yvon‐Durocher 《Ecology letters》2020,23(4):722-733
The efficiency of carbon sequestration by the biological pump could decline in the coming decades because respiration tends to increase more with temperature than photosynthesis. Despite these differences in the short‐term temperature sensitivities of photosynthesis and respiration, it remains unknown whether the long‐term impacts of global warming on metabolic rates of phytoplankton can be modulated by evolutionary adaptation. We found that respiration was consistently more temperature dependent than photosynthesis across 18 diverse marine phytoplankton, resulting in universal declines in the rate of carbon fixation with short‐term increases in temperature. Long‐term experimental evolution under high temperature reversed the short‐term stimulation of metabolic rates, resulting in increased rates of carbon fixation. Our findings suggest that thermal adaptation may therefore have an ameliorating impact on the efficiency of phytoplankton as primary mediators of the biological carbon pump. 相似文献
993.
Hao Wang Huiying Liu Guangmin Cao Zhiyuan Ma Yikang Li Fawei Zhang Xia Zhao Xinquan Zhao Lin Jiang Nathan J. Sanders Aime T. Classen Jin‐Sheng He 《Ecology letters》2020,23(4):701-710
Satellite data indicate significant advancement in alpine spring phenology over decades of climate warming, but corresponding field evidence is scarce. It is also unknown whether this advancement results from an earlier shift of phenological events, or enhancement of plant growth under unchanged phenological pattern. By analyzing a 35‐year dataset of seasonal biomass dynamics of a Tibetan alpine grassland, we show that climate change promoted both earlier phenology and faster growth, without changing annual biomass production. Biomass production increased in spring due to a warming‐induced earlier onset of plant growth, but decreased in autumn due mainly to increased water stress. Plants grew faster but the fast‐growing period shortened during the mid‐growing season. These findings provide the first in situ evidence of long‐term changes in growth patterns in alpine grassland plant communities, and suggest that earlier phenology and faster growth will jointly contribute to plant growth in a warming climate. 相似文献
994.
Lihua Zhang Fenghui Yuan Junhong Bai Hongtao Duan Xueying Gu Longyu Hou Yao Huang Mingan Yang Jin‐Sheng He Zhenhua Zhang Lijun Yu Changchun Song David A. Lipson Donatella Zona Walter Oechel Ivan A. Janssens Xiaofeng Xu 《Ecology letters》2020,23(5):821-830
Grassland ecosystems account for more than 10% of the global CH4 sink in soils. A 4‐year field experiment found that addition of P alone did not affect CH4 uptake and experimental addition of N alone significantly suppressed CH4 uptake, whereas concurrent N and P additions suppressed CH4 uptake to a lesser degree. A meta‐analysis including 382 data points in global grasslands corroborated these findings. Global extrapolation with an empirical modelling approach estimated that contemporary N addition suppresses CH4 sink in global grassland by 11.4% and concurrent N and P deposition alleviates this suppression to 5.8%. The P alleviation of N‐suppressed CH4 sink is primarily attributed to substrate competition, defined as the competition between ammonium and CH4 for the methane mono‐oxygenase enzyme. The N and P impacts on CH4 uptake indicate that projected increases in N and P depositions might substantially affect CH4 uptake and alter the global CH4 cycle. 相似文献
995.
Juan F. Espínola‐Novelo M. Teresa Gonzlez Aldo S. Pacheco Jos L. Luque Marcelo E. Oliva 《Ecology letters》2020,23(4):631-641
Parasite communities are similar to free‐living communities; decay of similarity over geographic distance, theory of island biogeography, species–area relationships and nestedness have been documented in both communities. Ecological succession has been studied in free‐living communities but has rarely been examined in parasite communities. We use seriation with replication to test the hypothesis that succession of parasite community structure is deterministic, thus developing throughout consecutive changes along the fish ontogeny, via a seriated pattern. 12 306 marine fishes (95 species) were studied. In 40 species, a seriated pattern was detected; 25 had a tendency towards a seriated pattern, and for 31 species, succession was at random. Age‐classes for each host species explained deterministic successional patterns for whole parasite communities and ectoparasites. Richness and number of age‐classes explained this pattern for endoparasites. Seriated successional pattern was evident for parasite communities of long‐lived marine fish, indicating that parasite communities follow sequential changes over time, like many free‐living communities. 相似文献
996.
Yaoqi Li Peter B. Reich Bernhard Schmid Nawal Shrestha Xiao Feng Tong Lyu Brian S. Maitner Xiaoting Xu Yichao Li Dongting Zou Zheng‐Hong Tan Xiangyan Su Zhiyao Tang Qinghua Guo Xiaojuan Feng Brian J. Enquist Zhiheng Wang 《Ecology letters》2020,23(6):1003-1013
A key challenge in ecology is to understand the relationships between organismal traits and ecosystem processes. Here, with a novel dataset of leaf length and width for 10 480 woody dicots in China and 2374 in North America, we show that the variation in community mean leaf size is highly correlated with the variation in climate and ecosystem primary productivity, independent of plant life form. These relationships likely reflect how natural selection modifies leaf size across varying climates in conjunction with how climate influences canopy total leaf area. We find that the leaf size?primary productivity functions based on the Chinese dataset can predict productivity in North America and vice‐versa. In addition to advancing understanding of the relationship between a climate‐driven trait and ecosystem functioning, our findings suggest that leaf size can also be a promising tool in palaeoecology for scaling from fossil leaves to palaeo‐primary productivity of woody ecosystems. 相似文献
997.
Jun-Seob Kim Sung-Jin Yoon Young-Jun Park Seon-Yeong Kim Choong-Min Ryu 《Environmental microbiology》2020,22(7):2485-2495
Interactions between pathogenic microorganisms and their hosts are varied and complex, encompassing open-field scale interactions to interactions at the molecular level. The capacity of plant pathogenic bacteria and fungi to cause diseases in human and animal systems was, until recently, considered of minor importance. However, recent evidence suggests that animal and human infections caused by plant pathogenic fungi, bacteria and viruses may have critical impacts on human and animal health and safety. This review analyses previous research on plant pathogens as causal factors of animal illness. In addition, a case study involving disruption of type III effector-mediated phagocytosis in a human cell line upon infection with an opportunistic phytopathogen, Pseudomonas syringae pv. tomato, is discussed. Further knowledge regarding the molecular interactions between plant pathogens and human and animal hosts is needed to understand the extent of disease incidence and determine mechanisms for disease prevention. 相似文献
998.
Amina‐Zahra Mouhoumed Ya‐Ni Mou Sen‐Miao Tong Sheng‐Hua Ying Ming‐Guang Feng 《Cellular microbiology》2020,22(10)
FK506‐sensitive proline rotamases (FPRs), also known as FK506‐binding proteins (FKBPs), can mediate immunosuppressive drug resistance in budding yeast but their physiological roles in filamentous fungi remain opaque. Here, we report that three FPRs (cytosolic/nuclear 12.15‐kD Fpr1, membrane‐associated 14.78‐kD Fpr2 and nuclear 50.43‐kD Fpr3) are all equally essential for cellular Ca2+ homeostasis and contribute significantly to calcineurin activity at different levels in the insect‐pathogenic fungus Beauveria bassiana although the deletion of fpr1 alone conferred resistance to FK506. Radial growth, conidiation, conidial viability and virulence were less compromised in the absence of fpr1 or fpr2 than in the absence of fpr3, which abolished almost all growth on scant media and reduced growth moderately on rich media. The Δfpr3 mutant was more sensitive to Na+, K+, Mn2+, Ca2+, Cu2+, metal chelate, heat shock and UVB irradiation than was Δfpr2 while both mutants were equally sensitive to Zn2+, Mg2+, Fe2+, H2O2 and cell wall‐perturbing agents. In contrast, the Δfpr1 mutant was less sensitive to fewer stress cues. Most of 32 examined genes involved in DNA damage repair, Na+/K+ detoxification or osmotolerance and Ca2+ homeostasis were downregulated sharply in Δfpr2 and Δfpr3 but rarely so affected in Δfpr1, coinciding well with their phenotypic changes. These findings uncover important, but differential, roles of three FPRs in the fungal adaptation to insect host and environment and provide novel insight into their essential roles in calcium signalling pathway. 相似文献
999.
Bethany S. Nichols Gerhard Leubner‐Metzger Vincent A. A. Jansen 《Ecology letters》2020,23(9):1370-1379
Environmental variability can lead to dispersal: why stay put if it is better elsewhere? Without clues about local conditions, the optimal strategy is often to disperse a set fraction of offspring. Many habitats contain environmentally differing sub‐habitats. Is it adaptive for individuals to sense in which sub‐habitat they find themselves, using environmental clues, and respond plastically by altering the dispersal rates? This appears to be done by some plants which produce dimorphic seeds with differential dispersal properties in response to ambient temperature. Here we develop a mathematical model to show, that in highly variable environments, not only does sensing promote plasticity of dispersal morph ratio, individuals who can sense their sub‐habitat and respond in this way have an adaptive advantage over those who cannot. With a rise in environmental variability due to climate change, our understanding of how natural populations persist and respond to changes has become crucially important. 相似文献
1000.
Hai‐Dong Li Linfang Tang Chenxi Jia Marcel Holyoak Jochen Fründ Xiaoqun Huang Zhishu Xiao 《Ecology letters》2020,23(8):1252-1262
Understanding how biodiversity and interaction networks change across environmental gradients is a major challenge in ecology. We integrated metacommunity and metanetwork perspectives to test species’ functional roles in bird–plant frugivory interactions in a fragmented forest landscape in Southwest China, with consequences for seed dispersal. Availability of fruit resources both on and under trees created vertical feeding stratification for frugivorous birds. Bird–plant interactions involving birds feeding only on‐the‐tree or both on and under‐the‐tree (shared) had a higher centrality and contributed more to metanetwork organisation than interactions involving birds feeding only under‐the‐tree. Moreover, bird–plant interactions associated with large‐seeded plants disproportionately contributed to metanetwork organisation and centrality. Consequently, on‐the‐tree and shared birds contributed more to metanetwork organisation whereas under‐the‐tree birds were more involved in local processes. We would expect that species’ roles in the metanetwork will translate into different conservation values for maintaining functioning of seed‐dispersal networks. 相似文献