keyword
MENU ▼
Read by QxMD icon Read
search

ecosystem collapse

keyword
https://www.readbyqxmd.com/read/27892495/quorum-regulated-resistance-of-vibrio-cholerae-against-environmental-bacteriophages
#1
M Mozammel Hoque, Iftekhar Bin Naser, S M Nayeemul Bari, Jun Zhu, John J Mekalanos, Shah M Faruque
Predation by bacteriophages can significantly influence the population structure of bacterial communities. Vibrio cholerae the causative agent of cholera epidemics interacts with numerous phages in the aquatic ecosystem, and in the intestine of cholera patients. Seasonal epidemics of cholera reportedly collapse due to predation of the pathogen by phages. However, it is not clear how sufficient number of the bacteria survive to seed the environment in the subsequent epidemic season. We found that bacterial cell density-dependent gene expression termed "quorum sensing" which is regulated by signal molecules called autoinducers (AIs) can protect V...
November 28, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27861926/leaf-vein-xylem-conduit-diameter-influences-susceptibility-to-embolism-and-hydraulic-decline
#2
Christine Scoffoni, Caetano Albuquerque, Craig R Brodersen, Shatara V Townes, Grace P John, Hervé Cochard, Thomas N Buckley, Andrew J McElrone, Lawren Sack
Ecosystems worldwide are facing increasingly severe and prolonged droughts during which hydraulic failure from drought-induced embolism can lead to organ or whole plant death. Understanding the determinants of xylem failure across species is especially critical in leaves, the engines of plant growth. If the vulnerability segmentation hypothesis holds within leaves, higher order veins that are most terminal in the plant hydraulic system should be more susceptible to embolism to protect the rest of the water transport system...
November 11, 2016: New Phytologist
https://www.readbyqxmd.com/read/27861768/community-disassembly-in-ephemeral-ecosystems
#3
Brian J O'Neill
Community disassembly is the non-random process of progressive species declines and losses. This process is usually studied to determine how various forces extirpate species, such as catastrophic disturbance, species invasions, habitat fragmentation, or unnatural/anthropogenic stressors. However, in ephemeral ecosystems, community disassembly is a natural and repeatable process. While many ephemeral ecosystems are aquatic (vernal pools, playa lakes, rock pools, saline lakes, phytotelmata, etc.), some disassembly patterns are applicable to other ecosystem types, including terrestrial ecosystems...
October 2, 2016: Ecology
https://www.readbyqxmd.com/read/27853564/bushmeat-hunting-and-extinction-risk-to-the-world-s-mammals
#4
William J Ripple, Katharine Abernethy, Matthew G Betts, Guillaume Chapron, Rodolfo Dirzo, Mauro Galetti, Taal Levi, Peter A Lindsey, David W Macdonald, Brian Machovina, Thomas M Newsome, Carlos A Peres, Arian D Wallach, Christopher Wolf, Hillary Young
Terrestrial mammals are experiencing a massive collapse in their population sizes and geographical ranges around the world, but many of the drivers, patterns and consequences of this decline remain poorly understood. Here we provide an analysis showing that bushmeat hunting for mostly food and medicinal products is driving a global crisis whereby 301 terrestrial mammal species are threatened with extinction. Nearly all of these threatened species occur in developing countries where major coexisting threats include deforestation, agricultural expansion, human encroachment and competition with livestock...
October 2016: Royal Society Open Science
https://www.readbyqxmd.com/read/27828993/predators-prey-and-habitat-structure-can-key-conservation-areas-and-early-signs-of-population-collapse-be-detected-in-neotropical-forests
#5
Benoit de Thoisy, Ibrahim Fayad, Luc Clément, Sébastien Barrioz, Eddy Poirier, Valéry Gond
Tropical forests with a low human population and absence of large-scale deforestation provide unique opportunities to study successful conservation strategies, which should be based on adequate monitoring tools. This study explored the conservation status of a large predator, the jaguar, considered an indicator of the maintenance of how well ecological processes are maintained. We implemented an original integrative approach, exploring successive ecosystem status proxies, from habitats and responses to threats of predators and their prey, to canopy structure and forest biomass...
2016: PloS One
https://www.readbyqxmd.com/read/27815533/early-warning-signals-of-regime-shifts-in-coupled-human-environment-systems
#6
Chris T Bauch, Ram Sigdel, Joe Pharaon, Madhur Anand
In complex systems, a critical transition is a shift in a system's dynamical regime from its current state to a strongly contrasting state as external conditions move beyond a tipping point. These transitions are often preceded by characteristic early warning signals such as increased system variability. However, early warning signals in complex, coupled human-environment systems (HESs) remain little studied. Here, we compare critical transitions and their early warning signals in a coupled HES model to an equivalent environment model uncoupled from the human system...
November 4, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27757544/marine-ecosystem-resilience-during-extreme-deoxygenation-the-early-jurassic-oceanic-anoxic-event
#7
Bryony A Caswell, Christopher L J Frid
Global warming during the Early Jurassic, and associated widespread ocean deoxygenation, was comparable in scale with the changes projected for the next century. This study quantifies the impact of severe global environmental change on the biological traits of marine communities that define the ecological roles and functions they deliver. We document centennial-millennial variability in the biological trait composition of Early Jurassic (Toarcian) seafloor communities and examine how this changed during the event using biological traits analysis...
October 18, 2016: Oecologia
https://www.readbyqxmd.com/read/27757421/empty-forest-or-empty-rivers-a-century-of-commercial-hunting-in-amazonia
#8
André P Antunes, Rachel M Fewster, Eduardo M Venticinque, Carlos A Peres, Taal Levi, Fabio Rohe, Glenn H Shepard
The Amazon basin is the largest and most species-rich tropical forest and river system in the world, playing a pivotal role in global climate regulation and harboring hundreds of traditional and indigenous cultures. It is a matter of intense debate whether the ecosystem is threatened by hunting practices, whereby an "empty forest" loses critical ecological functions. Strikingly, no previous study has examined Amazonian ecosystem resilience through the perspective of the massive 20th century international trade in furs and skins...
October 2016: Science Advances
https://www.readbyqxmd.com/read/27703075/collapse-of-insect-gut-symbiosis-under-simulated-climate-change
#9
Yoshitomo Kikuchi, Akiyo Tada, Dmitry L Musolin, Nobuhiro Hari, Takahiro Hosokawa, Kenji Fujisaki, Takema Fukatsu
: Global warming impacts diverse organisms not only directly but also indirectly via other organisms with which they interact. Recently, the possibility that elevated temperatures resulting from global warming may substantially affect biodiversity through disrupting mutualistic/parasitic associations has been highlighted. Here we report an experimental demonstration that global warming can affect a pest insect via suppression of its obligate bacterial symbiont. The southern green stinkbug Nezara viridula depends on a specific gut bacterium for its normal growth and survival...
October 4, 2016: MBio
https://www.readbyqxmd.com/read/27696581/predator-prey-interactions-among-permo-triassic-terrestrial-vertebrates-as-a-deterministic-factor-influencing-faunal-collapse-and-turnover
#10
Jacqueline Codron, Jennifer Botha-Brink, Daryl Codron, Adam K Huttenlocker, Kenneth D Angielczyk
Unlike modern mammalian communities, terrestrial Paleozoic and Mesozoic vertebrate systems were characterized by carnivore faunas that were as diverse as their herbivore faunas. The comparatively narrow food base available to carnivores in these paleosystems raises the possibility that predator-prey interactions contributed to unstable ecosystems by driving populations to extinction. Here we develop a model of predator-prey interactions based on diversity, abundance, and body size patterns observed in the Permo-Triassic vertebrate fossil record of the Karoo Basin, South Africa...
October 1, 2016: Journal of Evolutionary Biology
https://www.readbyqxmd.com/read/27660203/delayed-threshold-response-of-a-rodent-population-to-human-induced-landscape-change
#11
Andrey V Tchabovsky, Ludmila E Savinetskaya, Elena N Surkova, Natalia L Ovchinnikova, Ivan A Kshnyasev
Theory predicts that due to their resilience, ecosystems and populations are expected to respond to environmental changes not gradually, but in a nonlinear way with sudden abrupt shifts. However, it is not easy to observe and predict the state-and-transition dynamics in the real world because of time lags between exogenous perturbations and species response. Based on yearly surveys, during 21 years (1994-2014), we have studied population dynamics of a desert rodent (the midday gerbil, Meriones meridianus) in the rangelands of southern Russia under landscape change from desert to steppe caused by the drastic reduction of livestock after the collapse of the USSR in the early 1990s...
December 2016: Oecologia
https://www.readbyqxmd.com/read/27648228/early-warning-signals-detect-critical-impacts-of-experimental-warming
#12
Lauren Jarvis, Kevin McCann, Tyler Tunney, Gabriel Gellner, John M Fryxell
Earth's surface temperatures are projected to increase by ~1-4°C over the next century, threatening the future of global biodiversity and ecosystem stability. While this has fueled major progress in the field of physiological trait responses to warming, it is currently unclear whether routine population monitoring data can be used to predict temperature-induced population collapse. Here, we integrate trait performance theory with that of critical tipping points to test whether early warning signals can be reliably used to anticipate thermally induced extinction events...
September 2016: Ecology and Evolution
https://www.readbyqxmd.com/read/27643946/architecture-of-collapse-regime-shift-and-recovery-in-an-hierarchically-structured-marine-ecosystem
#13
Georgi M Daskalov, Laura Boicenco, Alexandre N Grishin, Luminita Lazar, Vesselina Mihneva, Vladislav A Shlyakhov, Mustafa Zengin
By the late 20th century, a series of events or 'natural experiments', for example the depletion of apex predators, extreme eutrophication and blooms of invasive species, had suggested that the Black Sea could be considered as a large ecosystem 'laboratory'. The events resulted in regime shifts cascading through all trophic levels, disturbing ecosystem functioning and damaging the water environment. Causal pathways by which the external (hydroclimate, overfishing) and internal (food web interactions) drivers provoke regime shifts are investigated...
September 19, 2016: Global Change Biology
https://www.readbyqxmd.com/read/27629038/spatially-cascading-effect-of-perturbations-in-experimental-meta-ecosystems
#14
Eric Harvey, Isabelle Gounand, Pravin Ganesanandamoorthy, Florian Altermatt
Ecosystems are linked to neighbouring ecosystems not only by dispersal, but also by the movement of subsidy. Such subsidy couplings between ecosystems have important landscape-scale implications because perturbations in one ecosystem may affect community structure and functioning in neighbouring ecosystems via increased/decreased subsidies. Here, we combine a general theoretical approach based on harvesting theory and a two-patch protist meta-ecosystem experiment to test the effect of regional perturbations on local community dynamics...
September 14, 2016: Proceedings. Biological Sciences
https://www.readbyqxmd.com/read/27619506/a-change-in-coral-extension-rates-and-stable-isotopes-after-el-ni%C3%A3-o-induced-coral-bleaching-and-regional-stress-events
#15
S Hetzinger, M Pfeiffer, W-Chr Dullo, J Zinke, D Garbe-Schönberg
Coral reefs are biologically diverse ecosystems threatened with effective collapse under rapid climate change, in particular by recent increases in ocean temperatures. Coral bleaching has occurred during major El Niño warming events, at times leading to the die-off of entire coral reefs. Here we present records of stable isotopic composition, Sr/Ca ratios and extension rate (1940-2004) in coral aragonite from a northern Venezuelan site, where reefs were strongly impacted by bleaching following the 1997-98 El Niño...
2016: Scientific Reports
https://www.readbyqxmd.com/read/27616433/hippopotamus-h-amphibius-diet-change-indicates-herbaceous-plant-encroachment-following-megaherbivore-population-collapse
#16
Kendra L Chritz, Scott A Blumenthal, Thure E Cerling, Hans Klingel
Megaherbivores (>1000 kg) are critical for ecosystem health and function, but face population collapse and extinction globally. The future of these megaherbivore-impoverished ecosystems is difficult to predict, though many studies have demonstrated increasing representation of C3 woody plants. These studies rely on direct observational data, however, and tools for assessing decadal-scale changes in African ecology without observation are lacking. We use isotopic records of historical common hippopotamus (Hippopotamus amphibius) canines to quantify herbaceous vegetation change in Queen Elizabeth National Park, Uganda following a period of civil unrest and poaching...
2016: Scientific Reports
https://www.readbyqxmd.com/read/27614563/benthic-surveys-of-the-historic-pearl-oyster-beds-of-qatar-reveal-a-dramatic-ecological-change
#17
D Smyth, I Al-Maslamani, M Chatting, B Giraldes
The study aimed to confirm the presence of historic oyster banks of Qatar and code the biotopes present. The research also collated historical records and scientific publications to create a timeline of fishery activity. The oyster banks where once an extremely productive economic resource however, intense overfishing, extreme environmental conditions and anthropogenic impacts caused a fishery collapse. The timeline highlighted the vulnerability of ecosystem engineering bivalves if overexploited. The current status of the oyster banks meant only one site could be described as oyster dominant...
September 7, 2016: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/27604853/terrestrial-biome-distribution-in-the-late-neogene-inferred-from-a-black-carbon-record-in-the-northeastern-equatorial-pacific
#18
Donghyun Kim, Yong Il Lee, Kiseong Hyeong, Chan Min Yoo
The appearance and expansion of C4 plants in the Late Cenozoic was a dramatic example of terrestrial ecological change. The fire hypothesis, which suggests fire as a major cause of C4 grassland is gaining support, yet a more detailed relationship between fire and vegetation-type change remains unresolved. We report the content and stable carbon isotope record of black carbon (BC) in a sediment core retrieved from the northeastern equatorial Pacific that covers the past 14.3 million years. The content record of BC suggests the development process of a flammable ecosystem...
2016: Scientific Reports
https://www.readbyqxmd.com/read/27585022/of-mussels-and-men
#19
Robert G Evans
Some species are more equal than others. Robert T. Paine (American ecologist, 1933-2016) discovered that if you remove starfish - what he called a "keystone species" - from a tide pool, the complex ecosystem collapses. Without the predator starfish, mussels choke out other animals and plants. This phenomenon is general. Sea otters eat the sea urchins that eat the kelp that provides food and habitat for other species. On the vast Serengeti plains, wildebeest "mow" the grass, protecting habitat for many other species...
August 2016: Healthcare Policy, Politiques de Santé
https://www.readbyqxmd.com/read/27573833/european-neolithic-societies-showed-early-warning-signals-of-population-collapse
#20
Sean S Downey, W Randall Haas, Stephen J Shennan
Ecosystems on the verge of major reorganization-regime shift-may exhibit declining resilience, which can be detected using a collection of generic statistical tests known as early warning signals (EWSs). This study explores whether EWSs anticipated human population collapse during the European Neolithic. It analyzes recent reconstructions of European Neolithic (8-4 kya) population trends that reveal regime shifts from a period of rapid growth following the introduction of agriculture to a period of instability and collapse...
August 30, 2016: Proceedings of the National Academy of Sciences of the United States of America
keyword
keyword
52009
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"