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171.
A continent‐wide study reveals clear relationships between regional abiotic conditions and post‐dispersal seed predation 下载免费PDF全文
John L. Orrock Elizabeth T. Borer Lars A. Brudvig Jennifer Firn Andrew S. MacDougall Brett A. Melbourne Louie H. Yang Dirk V. Baker Avi Bar‐Massada Michael J. Crawley Ellen I. Damschen Kendi F. Davies Daniel S. Gruner Adam D. Kay Eric Lind Rebecca L. McCulley Eric W. Seabloom 《Journal of Biogeography》2015,42(4):662-670
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R. PANADERO G. VARAS G. PAJARES F. MARKINA C. LÓPEZ P. DÍAZ A. PÉREZ‐CREO A. PRIETO P. DÍEZ‐BAÑOS P. MORRONDO 《Medical and veterinary entomology》2017,31(1):94-96
Subcutaneous larvae of Hypoderma spp. (Diptera: Oestridae) were detected in the dorsal region in 10 roe deer, Capreolus capreolus (Artiodactyla: Cervidae), hunted in central Spain between January and March 2016. All larvae were found in the inner side of the hide during the skinning of the animals. The study of the morphological features of eight larvae of different stages collected from two animals allowed the identification of Hypoderma actaeon Brauer. The small size (4–5 mm) of some of the first instars suggests that the internal lifecycle of H. actaeon may be exclusively subcutaneous. This is the first confirmation of H. actaeon in roe deer; however, further studies to assess the spread of the parasite and to follow the evolution of this myiasis in roe deer are needed. 相似文献
173.
Stacey A. McCormack Jessica Melbourne‐Thomas Rowan Trebilco Julia L. Blanchard Ben Raymond Andrew Constable 《Ecology and evolution》2021,11(1):227-241
Understanding regional‐scale food web structure in the Southern Ocean is critical to informing fisheries management and assessments of climate change impacts on Southern Ocean ecosystems and ecosystem services. Historically, a large component of Southern Ocean ecosystem research has focused on Antarctic krill, which provide a short, highly efficient food chain, linking primary producers to higher trophic levels. Over the last 15 years, the presence of alternative energy pathways has been identified and hypotheses on their relative importance in different regions raised. Using the largest circumpolar dietary database ever compiled, we tested these hypotheses using an empirical circumpolar comparison of food webs across the four major regions/sectors of the Southern Ocean (defined as south of 40°S) within the austral summer period. We used network analyses and generalizations of taxonomic food web structure to confirm that while Antarctic krill are dominant as the mid‐trophic level for the Atlantic and East Pacific food webs (including the Scotia Arc and Western Antarctic Peninsula), mesopelagic fish and other krill species are dominant contributors to predator diets in the Indian and West Pacific regions (East Antarctica and the Ross Sea). We also highlight how tracking data and habitat modeling for mobile top predators in the Southern Ocean show that these species integrate food webs over large regional scales. Our study provides a quantitative assessment, based on field observations, of the degree of regional differentiation in Southern Ocean food webs and the relative importance of alternative energy pathways between regions. 相似文献
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A. C. Risch S. Zimmermann M. Schütz E. T. Borer A. A. D. Broadbent M. C. Caldeira K. F. Davies N. Eisenhauer A. Eskelinen P. A. Fay F. Hagedorn J. M. H. Knops J. J. Lembrechts A. S. MacDougall R. L. McCulley B. A. Melbourne J. L. Moore S. A. Power E. W. Seabloom M. L. Silviera R. Virtanen L. Yahdjian R. Ochoa-Hueso 《Global Ecology and Biogeography》2023,32(6):904-918
Aim
The microbial metabolic quotient (MMQ; mg CO2-C/mg MBC/h), defined as the amount of microbial CO2 respired (MR; mg CO2-C/kg soil/h) per unit of microbial biomass C (MBC; mg C/kg soil), is a key parameter for understanding the microbial regulation of the carbon (C) cycle, including soil C sequestration. Here, we experimentally tested hypotheses about the individual and interactive effects of multiple nutrient addition (nitrogen + phosphorus + potassium + micronutrients) and herbivore exclusion on MR, MBC and MMQ across 23 sites (five continents). Our sites encompassed a wide range of edaphoclimatic conditions; thus, we assessed which edaphoclimatic variables affected MMQ the most and how they interacted with our treatments.Location
Australia, Asia, Europe, North/South America.Time period
2015–2016.Major taxa
Soil microbes.Methods
Soils were collected from plots with established experimental treatments. MR was assessed in a 5-week laboratory incubation without glucose addition, MBC via substrate-induced respiration. MMQ was calculated as MR/MBC and corrected for soil temperatures (MMQsoil). Using linear mixed effects models (LMMs) and structural equation models (SEMs), we analysed how edaphoclimatic characteristics and treatments interactively affected MMQsoil.Results
MMQsoil was higher in locations with higher mean annual temperature, lower water holding capacity and lower soil organic C concentration, but did not respond to our treatments across sites as neither MR nor MBC changed. We attributed this relative homeostasis to our treatments to the modulating influence of edaphoclimatic variables. For example, herbivore exclusion, regardless of fertilization, led to greater MMQsoil only at sites with lower soil organic C (< 1.7%).Main conclusions
Our results pinpoint the main variables related to MMQsoil across grasslands and emphasize the importance of the local edaphoclimatic conditions in controlling the response of the C cycle to anthropogenic stressors. By testing hypotheses about MMQsoil across global edaphoclimatic gradients, this work also helps to align the conflicting results of prior studies. 相似文献176.
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Efthymios Maneas Rosalind Aughwane Nam Huynh Wenfeng Xia Rehman Ansari Mithun Kuniyil Ajith Singh J. Ciaran Hutchinson Neil J. Sebire Owen J. Arthurs Jan Deprest Sebastien Ourselin Paul C. Beard Andrew Melbourne Tom Vercauteren Anna L. David Adrien E. Desjardins 《Journal of biophotonics》2020,13(4):1214-1229
Successful therapy of twin‐to‐twin transfusion syndrome requires accurate imaging to guide laser photocoagulation of the anastomosing placental vessels. Photoacoustic (PA) imaging is an alternative imaging method that provides contrast for hemoglobin, and in this study, it was used to visualize chorionic superficial and subsurface vasculature in human placentas. The strong potential of PA imaging to guide minimally invasive fetal therapies was demonstrated. Further details can be found in the article by Efthymios Maneas, Rosalind Aughwane, Nam Huynh, et al. ( e201900167 ).
179.
An autoclavable version of the Mackereth oxygen probe 总被引:1,自引:0,他引:1
180.