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Crowther, T.

Publications and source records attributed to Crowther, T..

3 recordsLinked to original sources

Niche constraints drive differences between mycorrhizal fungal guilds in future range shifts

Mycorrhizal fungi are a diverse and ubiquitous group of plant symbionts whose distribution strongly influences ecosystem function across the globe. Yet, until now, we do not have quantitative data on the range sizes of different mycorrhizal fungal taxa, limiting our capacity to forecast future shifts in community composition and function. Here, we use 115,924 DNA sequence-derived observations to map the distribution of 651 common mycorrhizal fungal taxa and forecast future changes to their range sizes. We demonstrate that climate, plant cover, and soil factors, particularly mean annual temperature, net primary productivity, and soil organic carbon, exert major control over mycorrhizal fungal distributions. Based on these drivers, the ecological niches of mycorrhizal fungi consistently differ between arbuscular and ectomycorrhizal functional guilds. Arbuscular mycorrhizal fungal taxa generally occupy a wider niche breadth than ectomycorrhizal fungi, occurring across larger ranges of climate, soil, plant cover, topography, and disturbance conditions. Our models also predict widespread decreases in the suitable range size of mycorrhizal fungal taxa under projected future global climates, with average ranges decreasing by 13.8% or ~2.2 million km2 under high emissions scenarios (ssp5-8.5). This decrease in projected range size will be most pronounced for ectomycorrhizal fungi, strongly linked to constraints from their smaller overall niches. By generating a global atlas of common mycorrhizal fungi and their associated environmental niche, we establish a critical baseline for widely suspected declines in global fungal biodiversity.

ecology↗

Transcriptomic Insights into the Responses in Leaves Storing Lipid Organelles under Different Irradiances

To increase the nutritional value of forage, transgenic ryegrass known as High Metabolizable Energy (HME) were previously generated that co-express cysteine-oleosin and diacylglycerol O-acyltransferase. HME not only accumulate lipids in the leaf but also has elevated CO2 assimilation and increased biomass. Shading is one of the most influencing factors for ryegrass growth environments particularly in swards. The aim of this study, therefore, was to determine the influence of irradiance levels on photosynthesis and gene expression in the HME leaves when compared with their corresponding non-transformant (NT). Under low light (150-250 {micro}mol m-2 s-1) and standard light (600-1000 {micro}mol m-2 s-1), the HME accumulated more lipid than NT. The previously reported elevated photosynthesis and increased biomass was observed when the HME were grown under standard light but not under low light. Under both light conditions, compared to NT, the HME had upregulated a number of transcripts involved in lipid metabolism, light capturing, photosynthesis, and sugar signalling network while downregulated genes participated in sugar and fructan biosynthesis. We further discuss how the HME differentially manipulated several genes other metabolic pathways including maintenance of redox homeostasis. Combined, the data suggests that the increased photosynthesis capacity in the HME likely corresponds to an increase of micro-lipid sink strength; these are influenced by available light energy and may be related to diffusional and biochemical activities of stomata. Overall, this work provides a clearly understanding of the changes in molecular and biochemical mechanisms underlying the carbon storing as leaf lipid sink of the HME ryegrass. One sentence summaryShading led to increase leaf lipid accumulation but limit the greater photosynthesis trait of high lipid ryegrass which may be related to limitation of biochemical activities of stomata.

molecular biology↗

Cities of the future, visualizing climate change to inspire actions

Combating against climate change requires unified action across all sectors of society. However, this collective action is precluded by the consensus gap between scientific knowledge and public opinion. A growing body of evidence suggests that facts do not persuade people to act. Instead, it is visualization - the ability to simulate relatable scenarios - is the most effective approach for motivating behavior change. Here, we exemplify this approach, using current climate projections to enable people to visualize cities of the future, rather than describing intangible climate variables. Analyzing city pairs for 520 major cities of the world, we characterize which cities will most closely resemble the climate conditions of which other major cities by 2050. On average, most cities will resemble cities that are over 1000km south, and 22% of cities will experience climate conditions that are not currently experienced by any existing major cities. We predict that Londons climate in 2050 will resemble Barcelonas climate today, Madrid will resemble to Marrakesh, Moscow to Sofia, Seattle to San Francisco, Stockholm to Budapest, Tokyo to Changsha, etc. Our approach illustrates how complex climate data can be packaged to provide tangible information. By allowing people to visualize their own climate futures, we hope to empower citizens, policy makers and scientists to visualize expected climate impacts and adapt decision making accordingly.

scientific communication and education↗