10 research outputs found
The James Webb Space Telescope Mission
Twenty-six years ago a small committee report, building on earlier studies,
expounded a compelling and poetic vision for the future of astronomy, calling
for an infrared-optimized space telescope with an aperture of at least .
With the support of their governments in the US, Europe, and Canada, 20,000
people realized that vision as the James Webb Space Telescope. A
generation of astronomers will celebrate their accomplishments for the life of
the mission, potentially as long as 20 years, and beyond. This report and the
scientific discoveries that follow are extended thank-you notes to the 20,000
team members. The telescope is working perfectly, with much better image
quality than expected. In this and accompanying papers, we give a brief
history, describe the observatory, outline its objectives and current observing
program, and discuss the inventions and people who made it possible. We cite
detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space
Telescope Overview, 29 pages, 4 figure
Interactions with juniper alter pinyon pine ectomycorrhizal fungal communities
Abstract. Belowground interactions can affect plants either directly or indirectly via their associated mycorrhizal fungi. However, few studies have experimentally examined the consequences of interspecific root interactions for these important mutualists in the field. We used a trenching experiment to examine how belowground interactions between pinyon pine and one-seed juniper affected the ectomycorrhizal (EM) fungal communities of pinyon pine. Three major findings emerged: (1) pinyons responded to the reduction of juniper roots with a near doubling of fine root biomass in just two years, (2) this increase in pinyon roots translated into a potential two-fold increase in EM abundance, and (3) the EM fungal communities of trenched trees differed significantly from controls largely due to a decrease in ascomycete fungi. Because species of EM fungi vary in the benefits they provide, changes in EM communities could have long-term consequences for host-plant establishment, growth, and survival. Belowground interactions with juniper may contribute to the high mortality of pinyons and the reduced diversity of EM fungi associated with recent droughts
Plant Reintroduction in a Changing ClimatePromises and Perils /
XX, 402 p. 36 illus.online resource
Does hybridization of endophytic symbionts in a native grass increase fitness in resource-limited environments?
Community-level physiological profiles of bacteria and fungi: plate type and incubation temperature influences on contrasting soils
Convergence in mycorrhizal fungal communities due to drought, plant competition, parasitism and susceptibility to herbivory: Consequences for fungi and host plants
Plants and mycorrhizal fungi influence each other’s abundance, diversity and distribution. How other biotic interactions affect the mycorrhizal symbiosis is less well understood. Likewise, we know little about the effects of climate change on the fungal component of the symbiosis or its function. We synthesized our long-term studies on the influence of mistletoe parasites, insect herbivores, competing trees, and drought on the ectomycorrhizal fungal communities associated with a foundation tree species of the southwestern United States, pinyon pine (Pinus edulis), and described how these changes feed back to affect host plant performance. We found that drought and all three of the biotic interactions studied resulted in similar shifts in ectomycorrhizal fungal community composition, demonstrating a convergence of the community towards dominance by a few closely related fungal taxa. Ectomycorrhizal fungi responded similarly to each of these stressors resulting in a predictable trajectory of community disassembly, consistent with ecological theory. Although we predicted that the fungal communities associated with trees stressed by drought, herbivory, competition, and parasitism would be poor mutualists, we found the opposite pattern in field studies. Our results suggest that climate change and the increased importance of herbivores, competitors and parasites that can be associated with it, may ultimately lead to reductions in ectomycorrhizal fungal diversity, but that the remaining fungal community may be beneficial to host trees under the current climate and the warmer, drier climate predicted for the future
Establishing the phylogenetic origin, history, and age of the narrow endemic Viola guadalupensis
Uptake of long acting reversible contraception following integrated couples HIV and fertility goal-based family planning counselling in Catholic and non-Catholic, urban and rural government health centers in Kigali, Rwanda
The James Webb Space Telescope Mission
Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least 4 m. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the 6.5 m James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 yr, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit