scholarly journals Vegetation and microbes interact to preserve carbon in many wooded peatlands

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Hongjun Wang ◽  
Jianqing Tian ◽  
Huai Chen ◽  
Mengchi Ho ◽  
Rytas Vilgalys ◽  
...  

AbstractPeatlands have persisted as massive carbon sinks over millennia, even during past periods of climate change. The commonly accepted theory of abiotic controls (mainly anoxia and low temperature) over carbon decomposition cannot fully explain how vast low-latitude shrub/tree dominated (wooded) peatlands consistently accrete peat under warm and seasonally unsaturated conditions. Here we show, by comparing the composition and ecological traits of microbes between Sphagnum- and shrub-dominated peatlands, that slow-growing microbes decisively dominate the studied shrub-dominated peatlands, concomitant with plant-induced increases in highly recalcitrant carbon and phenolics. The slow-growing microbes metabolize organic matter thirty times slower than the fast-growing microbes that dominate our Sphagnum-dominated site. We suggest that the high-phenolic shrub/tree induced shifts in microbial composition may compensate for positive effects of temperature and/or drought on metabolism over time in peatlands. This biotic self-sustaining process that modulates abiotic controls on carbon cycling may improve projections of long-term, climate-carbon feedbacks in peatlands.

2020 ◽  
Author(s):  
Hongjun Wang ◽  
Jianqing Tian ◽  
Huai Chen ◽  
Mengchi Ho ◽  
Rytas Vilgalys ◽  
...  

AbstractPeatlands have persisted as massive carbon sinks over millennia, even during past periods of climate change. The commonly accepted theory of abiotic controls (mainly anoxia and low temperature) over carbon decomposition cannot explain how vast low-latitude wooded peatlands consistently accrete peat under warm and seasonally unsaturated conditions. Similarly, that theory cannot accurately project the decomposition rate in boreal peatlands where warming and drought have decreased Sphagnum and increased shrub expansion. Here, by comparing composition and ecological traits of microbes between Sphagnum- and shrub-dominated peatlands, we present a previously unrecognized natural course that curbs carbon loss against climate change. Slow-growing microbes decisively dominate the studied wooded peatlands, concomitant with plant-induced, high recalcitrant carbon and phenolics. The slow-growing microbes inherently metabolize organic matter slowly. However, the fast-growing microbes that dominate our Sphagnum site (most boreal peatlands as well) decomposed labile carbon >30 times faster than the slow-growing microbes. We show that the high-phenolic shrub/tree induced shifts in microbial composition may compensate for positive effects of temperature and/or drought on metabolism over time in peatlands. This biotic self-sustaining process that modulates abiotic controls on carbon cycling may help better project long-term climate-carbon feedbacks in peatlands.


2021 ◽  
Author(s):  
Ellen A.R. Welti ◽  
Petr Zajicek ◽  
Manfred Ayasse ◽  
Tim Bornholdt ◽  
Jörn Buse ◽  
...  

ABSTRACTWe examine the effects of climate and land cover on flying insect biomass using an ecological gradients approach and data from the first year of a new, ongoing, standardized German Malaise Trap Program coordinated by the German Long-Term Ecological Research network. We hypothesized that biomass would display a unimodal relationship with temperature, consistent with thermal performance theory. We additionally predicted biomass would decrease with precipitation due to reduced flying activity, and would decrease in areas with more heavily human-modified land cover. Flying insect biomass was quantified from malaise traps at 84 locations across Germany throughout the 2019 growing season. We used an Akaike information criterion approach to parse drivers of temperature, deviation in 2019 temperature from long-term averages, precipitation, land cover, geographic coordinates, elevation, and sampling period. We further examined how effects of temperature on insect biomass change across space by testing for interactions between temperature and latitude. Flying insect biomass increased linearly with monthly temperature across all samples. However, positive effects of temperature on flying insect biomass declined with latitude, suggesting the warm 2019 summer temperatures in southern Germany may have exceeded local insect optimums, and highlighting the spatial variation in climate change-driven impacts on insect communities. Land cover explained less variation in insect biomass, with the largest effect being lower biomass in forested sites. Large-scale, standardized biodiversity monitoring like the German Malaise Trap Program are critical to meet the challenge of disentangling the roles of multiple drivers on insect communities.


2016 ◽  
Vol 64 (2) ◽  

Strategies to improve cognitive aging are highly needed. Among those, promotion of exercise and physical activity appears as one of the most attractive and beneficial intervention. Indeed, results from basic and clinical studies suggest that exercise and physical activity have positive effects on cognition in older persons without cognitive impairment, as well as in those with dementia. Despite inconsistent results, aerobic exercise appears to have the strongest potential to enhance cognition. However, even limited periods of walking (45 minutes, three times a week, over a 6-month period) have also been shown to enhance cognition, particularly executive functions. Changing long-term lifestyle habits in these older persons remains a critical challenge and attractive programs susceptible to gain adherence are needed to succeed in achieving improved cognitive aging.


2020 ◽  
Vol 9 (2) ◽  
pp. 115-127
Author(s):  
Lena S. Jia ◽  
Jessica A. Gold

Hallucinogens are a drug class that is growing in popularity with college students. Recent experimental trends, such as microdosing, have helped promote the use of hallucinogens on campus, and students may be tempted to use these substances due to their beliefs about the drugs’ positive effects on mood. Although hallucinogens are not currently an established form of medical therapy, studies have shown that they have significant benefits as adjunctive treatments for psychological disorders. However, the recreational use of these drugs in college students often occurs in uncontrolled doses or with drug mixing, which is often dangerous. Furthermore, students with mental health disorders may have their symptoms masked by hallucinogenic drug use, which could delay treatment and have serious consequences. Long-term use of these drugs may also result in tolerance or hallucinogen persisting perception disorder. This article attempts to review current information regarding hallucinogen use and how it applies to the college population.


2021 ◽  
Vol 13 ◽  
pp. 1759720X2110069
Author(s):  
Rebecca J. Moon ◽  
Elizabeth M. Curtis ◽  
Stephen J. Woolford ◽  
Shanze Ashai ◽  
Cyrus Cooper ◽  
...  

Optimisation of skeletal mineralisation in childhood is important to reduce childhood fracture and the long-term risk of osteoporosis and fracture in later life. One approach to achieving this is antenatal vitamin D supplementation. The Maternal Vitamin D Osteoporosis Study is a randomised placebo-controlled trial, the aim of which was to assess the effect of antenatal vitamin D supplementation (1000 IU/day cholecalciferol) on offspring bone mass at birth. The study has since extended the follow up into childhood and diversified to assess demographic, lifestyle and genetic factors that determine the biochemical response to antenatal vitamin D supplementation, and to understand the mechanisms underpinning the effects of vitamin D supplementation on offspring bone development, including epigenetics. The demonstration of positive effects of maternal pregnancy vitamin D supplementation on offspring bone development and the delineation of underlying biological mechanisms inform clinical care and future public-health policies.


2021 ◽  
pp. 1-3
Author(s):  
Anda David ◽  
Frédéric Docquier

How do weather shocks influence human mobility and poverty, and how will long-term climate change affect future migration over the course of the 21st century? These questions have gained unprecedented attention in public debates as global warming is already having severe impacts around the world, and prospects for the coming decades get worse. Low-latitude countries in general, and their agricultural areas in particular, have contributed the least to climate change but are the most adversely affected. The effect on people's voluntary and forced displacements is of major concern for both developed and developing countries. On 18 October 2019, Agence Française de Développement (AFD) and Luxembourg Institute of Socio-Economic Research (LISER) organized a workshop on Climate Migration with the aim of uncovering the mechanisms through which fast-onset variables (such as weather anomalies, storms, hurricanes, torrential rains, floods, landslides, etc.) and slow-onset variables (such as temperature trends, desertification, rising sea level, coastal erosion, etc.) influence both people's incentives to move and mobility constraints. This special issue gathers five papers prepared for this workshop, which shed light on (or predict) the effect of extreme weather shocks and long-term climate change on human mobility, and stress the implications for the development community.


Life ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 246
Author(s):  
Felix C.F. Schmitt ◽  
Martin Schneider ◽  
William Mathejczyk ◽  
Markus A. Weigand ◽  
Jane C. Figueiredo ◽  
...  

Changes in the gut microbiome have already been associated with postoperative complications in major abdominal surgery. However, it is still unclear whether these changes are transient or a long-lasting effect. Therefore, the aim of this prospective clinical pilot study was to examine long-term changes in the gut microbiota and to correlate these changes with the clinical course of the patient. Methods: In total, stool samples of 62 newly diagnosed colorectal cancer patients undergoing primary tumor resection were analyzed by 16S-rDNA next-generation sequencing. Stool samples were collected preoperatively in order to determine the gut microbiome at baseline as well as at 6, 12, and 24 months thereafter to observe longitudinal changes. Postoperatively, the study patients were separated into two groups—patients who suffered from postoperative complications (n = 30) and those without complication (n = 32). Patients with postoperative complications showed a significantly stronger reduction in the alpha diversity starting 6 months after operation, which does not resolve, even after 24 months. The structure of the microbiome was also significantly altered from baseline at six-month follow-up in patients with complications (p = 0.006). This was associated with a long-lasting decrease of a large number of species in the gut microbiota indicating an impact in the commensal microbiota and a long-lasting increase of Fusobacterium ulcerans. The microbial composition of the gut microbiome shows significant changes in patients with postoperative complications up to 24 months after surgery.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Anders Kärnä

AbstractIncomplete capital markets and credit constraints for small and medium-sized enterprises (SMEs) are often considered obstacles to economic growth, thus motivating government interventions in capital markets. While such policies are common, it is less clear to what extent these interventions result in firm growth or to which firms interventions should be targeted. Using a unique dataset with information about state bank loans targeting credit-constrained SMEs in Sweden with and without complementary private bank loans, this paper contributes to the literature by studying how these loans affect the targeted firms for several outcome variables. The results suggest that the loans create a one-off increase in investments, with long-term, positive effects for sales and labor productivity but only for firms with 10 or fewer employees. Increased access to capital by firms can therefore produce increases in economic output but only in a specific type of firm. This insight is of key importance in designing policy if the aim is to increase economic growth.


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