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https://www.readbyqxmd.com/read/28214117/evaluating-carbon-fluxes-of-global-forest-ecosystems-by-using-an-individual-tree-based-model-forcchn
#1
Jianyong Ma, Herman H Shugart, Xiaodong Yan, Cougui Cao, Shuang Wu, Jing Fang
The carbon budget of forest ecosystems, an important component of the terrestrial carbon cycle, needs to be accurately quantified and predicted by ecological models. As a preamble to apply the model to estimate global carbon uptake by forest ecosystems, we used the CO2 flux measurements from 37 forest eddy-covariance sites to examine the individual tree-based FORCCHN model's performance globally. In these initial tests, the FORCCHN model simulated gross primary production (GPP), ecosystem respiration (ER) and net ecosystem production (NEP) with correlations of 0...
February 14, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28213297/retention-of-silver-nano-particles-and-silver-ions-in-calcareous-soils-influence-of-soil-properties
#2
Samaneh Rahmatpour, Mehran Shirvani, Mohammad R Mosaddeghi, Mehdi Bazarganipour
The rapid production and application of silver nanoparticles (AgNPs) have led to significant release of AgNPs into the terrestrial environments. Once released into the soil, AgNPs could enter into different interactions with soil particles which play key roles in controlling the fate and transport of these nanoparticles. In spite of that, experimental studies on the retention of AgNPs in soils are very scarce. Hence, the key objective of this research was to find out the retention behavior of AgNPs and Ag(I) ions in a range of calcareous soils...
February 14, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28211329/first-report-of-perfluoroalkyl-substances-in-south-african-odonata
#3
Velesia Lesch, Hindrik Bouwman, Ayako Kinoshita, Yasuyuki Shibata
Perfluorinated substances are global and ubiquitous pollutants. However, very little is known about these substances in invertebrates, and even less in terrestrial invertebrates in particular. We analysed adult male dragonflies from six sites in South Africa for perfluoroalkyl substances (PFASs), including perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluro-n-undecanoic acid (PFUnA), perfluoro-n-dodecanoic acid (PFDoA), perfluorohexanoic acid (PFHxA), and perfluorohexane sulfonic acid (PFHxS)...
February 4, 2017: Chemosphere
https://www.readbyqxmd.com/read/28210860/a-heat-vulnerability-index-to-improve-urban-public-health-management-in-san-juan-puerto-rico
#4
Pablo Méndez-Lázaro, Frank E Muller-Karger, Daniel Otis, Matthew J McCarthy, Ernesto Rodríguez
Increased frequency and length of high heat episodes are leading to more cardiovascular issues and asthmatic responses among the population of San Juan, the capital of the island of Puerto Rico, USA. An urban heat island effect, which leads to foci of higher temperatures in some urban areas, can raise heat-related mortality. The objective of this research is to map the risk of high temperature in particular locations by creating heat maps of the city of San Juan. The heat vulnerability index (HVI) maps were developed using images collected by satellite-based remote sensing combined with census data...
February 17, 2017: International Journal of Biometeorology
https://www.readbyqxmd.com/read/28209363/origin-and-distribution-of-hydrocarbons-and-organic-matter-in-the-surficial-sediments-of-the-sfax-kerkennah-channel-tunisia-southern-mediterranean-sea
#5
Hatem Zaghden, Marc Tedetti, Sami Sayadi, Mohamed Moncef Serbaji, Boubaker Elleuch, Alain Saliot
We investigated the origin and distribution of aliphatic and polycyclic aromatic hydrocarbons (AHs and PAHs) and organic matter (OM) in surficial sediments of the Sfax-Kerkennah channel in the Gulf of Gabès (Tunisia, Southern Mediterranean Sea). TOC, AH and PAH concentrations ranged 2.3-11.7%, 8-174μgg(-1)sed.dw and 175-10,769ngg(-1)sed.dw, respectively. The lowest concentrations were recorded in the channel (medium sand sediment) and the highest ones in the Sfax harbor (very fine sand sediment). AHs, PAHs and TOC were not correlated for most of the stations...
February 13, 2017: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/28202811/small-birds-big-effects-the-little-auk-alle-alle-transforms-high-arctic-ecosystems
#6
Ivan González-Bergonzoni, Kasper L Johansen, Anders Mosbech, Frank Landkildehus, Erik Jeppesen, Thomas A Davidson
In some arctic areas, marine-derived nutrients (MDN) resulting from fish migrations fuel freshwater and terrestrial ecosystems, increasing primary production and biodiversity. Less is known, however, about the role of seabird-MDN in shaping ecosystems. Here, we examine how the most abundant seabird in the North Atlantic, the little auk (Alle alle), alters freshwater and terrestrial ecosystems around the North Water Polynya (NOW) in Greenland. We compare stable isotope ratios (δ(15)N and δ(13)C) of freshwater and terrestrial biota, terrestrial vegetation indices and physical-chemical properties, productivity and community structure of fresh waters in catchments with and without little auk colonies...
February 22, 2017: Proceedings. Biological Sciences
https://www.readbyqxmd.com/read/28193590/fast-identification-of-microplastics-in-complex-environmental-samples-by-a-thermal-degradation-method
#7
Erik Dümichen, Paul Eisentraut, Claus Gerhard Bannick, Anne-Kathrin Barthel, Rainer Senz, Ulrike Braun
In order to determine the relevance of microplastic particles in various environmental media, comprehensive investigations are needed. However, no analytical method exists for fast identification and quantification. At present, optical spectroscopy methods like IR and RAMAN imaging are used. Due to their time consuming procedures and uncertain extrapolation, reliable monitoring is difficult. For analyzing polymers Py-GC-MS is a standard method. However, due to a limited sample amount of about 0.5 mg it is not suited for analysis of complex sample mixtures like environmental samples...
February 3, 2017: Chemosphere
https://www.readbyqxmd.com/read/28163780/efficient-molasses-fermentation-under-high-salinity-by-inocula-of-marine-and-terrestrial-origin
#8
Alberto Scoma, Marta Coma, Frederiek-Maarten Kerckhof, Nico Boon, Korneel Rabaey
BACKGROUND: Molasses is a dense and saline by-product of the sugar agroindustry. Its high organic content potentially fuels a myriad of renewable products of industrial interest. However, the biotechnological exploitation of molasses is mainly hampered by the high concentration of salts, an issue that is nowadays tackled through dilution. In the present study, the performance of microbial communities derived from marine sediment was compared to that of communities from a terrestrial environment (anaerobic digester sludge)...
2017: Biotechnology for Biofuels
https://www.readbyqxmd.com/read/28162041/n-hexanal-and-z-3-hexenal-are-generated-from-arachidonic-acid-and-linolenic-acid-by-a-lipoxygenase-in-marchantia-polymorpha-l
#9
Moataz M Tawfik, Katsuyuki T Yamato, Takayuki Kohchi, Takao Koeduka, Kenji Matsui
Most terrestrial plants form green leaf volatiles (GLVs), which are mainly composed of six-carbon (C6) compounds. In our effort to study the distribution of the ability of lipoxygenase (LOX) to form GLVs, we found that a liverwort, Marchantia polymorpha, formed n-hexanal and (Z)-3-hexenal. Some LOXs execute a secondary reaction to form short chain volatiles. One of the LOXs from M. polymorpha (MpLOX7) oxygenized arachidonic and α-linolenic acids at almost equivalent efficiency and formed C6-aldehydes during its catalysis; these are likely formed from hydroperoxides of arachidonic and α-linolenic acids, with a cleavage of the bond between carbon at the base of the hydroperoxy group and carbon of double bond, which is energetically unfavorable...
February 6, 2017: Bioscience, Biotechnology, and Biochemistry
https://www.readbyqxmd.com/read/28157152/toward-an-assessment-of-the-global-inventory-of-present-day-mercury-releases-to-freshwater-environments
#10
David Kocman, Simon J Wilson, Helen M Amos, Kevin H Telmer, Frits Steenhuisen, Elsie M Sunderland, Robert P Mason, Peter Outridge, Milena Horvat
Aquatic ecosystems are an essential component of the biogeochemical cycle of mercury (Hg), as inorganic Hg can be converted to toxic methylmercury (MeHg) in these environments and reemissions of elemental Hg rival anthropogenic Hg releases on a global scale. Quantification of effluent Hg releases to aquatic systems globally has focused on discharges to the global oceans, rather than contributions to freshwater systems that affect local exposures and risks associated with MeHg. Here we produce a first-estimate of sector-specific, spatially resolved global aquatic Hg discharges to freshwater systems...
February 1, 2017: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/28153920/the-liverwort-marchantia-drives-alternative-electron-flow-using-a-flavodiiron-protein-to-protect-psi
#11
Ginga Shimakawa, Kimitsune Ishizaki, Shigeyuki Tsukamoto, Moeko Tanaka, Takehiro Sejima, Chikahiro Miyake
The diffusion efficiency of O2 in atmosphere, like that of CO2, is approximately 10(4) times greater than that in aqueous environments. Consequently, terrestrial photosynthetic organisms need mechanisms to protect against potential oxidative damage. The liverwort Marchantia polymorpha, a basal land plant, has habitats where it is exposed to both water and the atmosphere. Furthermore, like cyanobacteria, M. polymorpha has genes encoding flavodiiron proteins (FLV). In cyanobacteria, FLVs mediate O2-dependent alternative electron flow (AEF) to suppress production of reactive oxygen species...
February 2, 2017: Plant Physiology
https://www.readbyqxmd.com/read/28145053/challenging-terrestrial-biosphere-models-with-data-from-the-long-term-multi-factor-prairie-heating-and-co2-enrichment-experiment
#12
Martin G De Kauwe, Belinda E Medlyn, Anthony P Walker, Sönke Zaehle, Shinichi Asao, Bertrand Guenet, Anna B Harper, Thomas Hickler, Atul Jain, Yiqi Luo, Xingjie Lu, Kristina Luus, William J Parton, Shijie Shu, Ying-Ping Wang, Christian Werner, Jianyang Xia, Elise Pendall, Jack A Morgan, Edmund M Ryan, Yolima Carrillo, Feike A Dijkstra, Tamara J Zelikova, Richard J Norby
Multi-factor experiments are often advocated as important for advancing terrestrial biosphere models (TBMs), yet to date such models have only been tested against single-factor experiments. We applied 10 TBMs to the multi-factor Prairie Heating and CO2 Enrichment (PHACE) experiment in Wyoming, USA. Our goals were to investigate how multi-factor experiments can be used to constrain models, and to identify a road map for model improvement. We found models performed poorly in current ambient conditions; there was a wide spread in simulated above-ground net primary productivity (range: 31-390 g C m(-2) yr(-1) )...
February 1, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28142209/changes-in-vegetation-phenology-are-not-reflected-in-atmospheric-co2-and-13-c-12-c-seasonality
#13
Alemu Gonsamo, Petra D'Odorico, Jing M Chen, Chaoyang Wu, Nina Buchmann
Northern terrestrial ecosystems have shown global warming-induced advances in start, delays in end, and thus increased lengths of growing season and gross photosynthesis in recent decades. The tradeoffs between seasonal dynamics of two opposing fluxes, CO2 uptake through photosynthesis and release through respiration, determine the influence of the terrestrial ecosystem on the atmospheric CO2 and (13) C/(12) C seasonality. Here we use four CO2 observation stations in the Northern Hemisphere, namely Alert, La Jolla, Point Barrow and Mauna Loa Observatory, to determine how changes in vegetation productivity and phenology, respiration, and air temperature affect both, the atmospheric CO2 and (13) C/(12) C seasonality...
January 31, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28139649/climate-change-reduces-extent-of-temperate-drylands-and-intensifies-drought-in-deep-soils
#14
Daniel R Schlaepfer, John B Bradford, William K Lauenroth, Seth M Munson, Britta Tietjen, Sonia A Hall, Scott D Wilson, Michael C Duniway, Gensuo Jia, David A Pyke, Ariuntsetseg Lkhagva, Khishigbayar Jamiyansharav
Drylands cover 40% of the global terrestrial surface and provide important ecosystem services. While drylands as a whole are expected to increase in extent and aridity in coming decades, temperature and precipitation forecasts vary by latitude and geographic region suggesting different trajectories for tropical, subtropical, and temperate drylands. Uncertainty in the future of tropical and subtropical drylands is well constrained, whereas soil moisture and ecological droughts, which drive vegetation productivity and composition, remain poorly understood in temperate drylands...
January 31, 2017: Nature Communications
https://www.readbyqxmd.com/read/28131480/characteristics-of-dissolved-organic-matter-dom-and-relationship-with-dissolved-mercury-in-xiaoqing-river-laizhou-bay-estuary-bohai-sea-china
#15
Tao Jiang, Ulf Skyllberg, Erik Björn, Nelson W Green, Jianhui Tang, Dingyong Wang, Jie Gao, Chuxian Li
Because of heterogeneous properties, dissolved organic matter (DOM) is known to control the environmental fate of a variety of organic pollutants and trace metals in aquatic systems. Here we report absorptive and fluorescence properties of DOM, in concurrence with concentrations of dissolved mercury (Hg), along the Xiaoqing River-Laizhou Bay estuary system located in the Bohai Sea of China. A mixing model consisting of the two end-members terrestrial and aquatic DOM demonstrated that terrestrial signatures decreased significantly from the river into the estuary...
January 25, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28128071/the-geomycology-of-elemental-cycling-and-transformations-in-the-environment
#16
Geoffrey Michael Gadd
Geomicrobiology addresses the roles of microorganisms in geological and geochemical processes, and geomycology is a part of this topic focusing on the fungi. Geoactive roles of fungi include organic and inorganic transformations important in nutrient and element cycling, rock and mineral bioweathering, mycogenic biomineral formation, and metal-fungal interactions. Lichens and mycorrhizas are significant geoactive agents. Organic matter decomposition is important for cycling of major biomass-associated elements, e...
January 2017: Microbiology Spectrum
https://www.readbyqxmd.com/read/28122788/causes-of-rapid-carrion-beetle-coleoptera-silphidae-death-in-flooded-pitfall-traps-response-to-soil-flooding-immersion-tolerance-and-swimming-behavior
#17
Michael C Cavallaro, M Christopher Barnhart, W Wyatt Hoback
Terrestrial insects in water can often delay or escape drowning by floating and swimming. However, we observed that flooding of pitfall traps baited with rotting carrion results in high overnight mortality of captured beetles and reasoned that this risk may be enhanced by microbial respiration. By assessing carrion beetle (Coleoptera: Silphidae) response to flooding, tolerance to immersion, and swimming behavior, we offer insights to this cause of death and beetle behavioral physiology. Response of buried Nicrophorus orbicollis Say to soil flooding resulted in beetles moving to the soil surface...
January 24, 2017: Environmental Entomology
https://www.readbyqxmd.com/read/28122207/does-a-protective-message-reduce-the-impact-of-an-advergame-promoting-unhealthy-foods-to-children-an-experimental-study-in-spain-and-the-netherlands
#18
Frans Folkvord, Francisco Lupiáñez-Villanueva, Cristiano Codagnone, Francesco Bogliacino, Giuseppe Veltri, George Gaskell
The weight of evidence points to the advertising of food affecting food consumption, especially among children. Such advertising often promotes unhealthy foods. Current policy deliberations focus on developing effective 'protective' messages to increase advertising literacy and consequent scepticism about advertising targeting children. This study examined whether incorporating a 'protective' message in an advergame promoting energy-dense snacks would reduce children's snack intake. A randomized between-subject design was conducted in the Netherlands (N = 215) and Spain (N = 382) with an advergame promoting either energy-dense snacks or nonfood products...
January 22, 2017: Appetite
https://www.readbyqxmd.com/read/28116045/estimating-plant-abundance-using-inflated-beta-distributions-applied-learnings-from-a-lichen-caribou-ecosystem
#19
Jonah L Keim, Philip D DeWitt, J Jeremy Fitzpatrick, Noemie S Jenni
Quantifying abundance and distribution of plant species can be difficult because data are often inflated with zero values due to rarity or absence from many ecosystems. Terrestrial fruticose lichens (Cladonia and Cetraria spp.) occupy a narrow ecological niche and have been linked to the diets of declining caribou and reindeer populations (Rangifer tarandus) across their global distribution, and conditions related to their abundance and distribution are not well understood. We attempted to measure effects related to the occupancy and abundance of terrestrial fruticose lichens by sampling and simultaneously modeling two discrete conditions: absence and abundance...
January 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28099525/polyethylene-glycol-camouflaged-earthworm-hemoglobin
#20
Vivek P Jani, Alborz Jelvani, Selamawit Moges, Parimala Nacharaju, Camille Roche, David Dantsker, Andre Palmer, Joel M Friedman, Pedro Cabrales
Nearly 21 million components of blood and whole blood and transfused annually in the United States, while on average only 13.6 million units of blood are donated. As the demand for Red Blood Cells (RBCs) continues to increase due to the aging population, this deficit will be more significant. Despite decades of research to develop hemoglobin (Hb) based oxygen (O2) carriers (HBOCs) as RBC substitutes, there are no products approved for clinical use. Lumbricus terrestris erythrocruorin (LtEc) is the large acellular O2 carrying protein complex found in the earthworm Lumbricus terrestris...
2017: PloS One
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