scholarly journals Long-term predictions of ecosystem acidification and recovery

2016 ◽  
Vol 568 ◽  
pp. 381-390 ◽  
Author(s):  
Richard A. Skeffington ◽  
B. Jack Cosby ◽  
Paul G. Whitehead
Keyword(s):  
Acidification And Recovery

scholarly journals Long-term development of acid deposition (1880–2030) in sensitive freshwater regions in Europe

2003 ◽  
Vol 7 (4) ◽  
pp. 436-446 ◽  
Author(s):  
W. Schöpp ◽  
M. Posch ◽  
S. Mylona ◽  
M. Johansson
Keyword(s):  
Time Series ◽  
Acid Deposition ◽  
Driving Forces ◽  
Freshwater Ecosystems ◽  
Time Interval ◽  
Transfer Coefficients ◽  
Current Emission ◽  
Acidification And Recovery ◽  
The Eu

Abstract. Time series of the deposition of acidifying substances are a pre-requisite for the study of the acidification and recovery of ecosystems such as surface waters. This paper reports the derivation and calculation of deposition trends of the potentially acidifying compounds SO2, NOx and NH3 in sensitive freshwater regions in Europe studied in the EU-funded RECOVER: 2010 project. The time interval covered is 151 years: from 1880, which can be considered as the pre-industrial era in most countries, to 2030, taking into account the consequences of current emission reduction agreements in Europe. The historic and predicted emissions for European countries are used to calculate the deposition development in the study areas, using meteorologically averaged atmospheric source-receptor transfer coefficients derived from the EMEP Lagrangian acid deposition model. These time series were used as driving forces for the application of the dynamic acidification model MAGIC to study the acidification and recovery of sensitive freshwater ecosystems in Europe. Keywords: acid deposition, historic depositions, sensitive lake regions, Europe

The influence of forestry on acidification and recovery: Insights from long-term hydrochemical and invertebrate data

2014 ◽  
Vol 37 ◽  
pp. 317-329 ◽  
Author(s):  
I.A. Malcolm ◽  
C.N. Gibbins ◽  
R.J. Fryer ◽  
J. Keay ◽  
D. Tetzlaff ◽  
...  
Keyword(s):  
Acidification And Recovery

Separating the effects on water chemistry of climate variation and experimental manipulation in the long-term acidification and recovery of lakesThis paper is part of the series “Forty Years of Aquatic Research at the Experimental Lakes Area”.

2009 ◽  
Vol 66 (11) ◽  
pp. 1864-1874 ◽  
Author(s):  
Raymond H. Hesslein ◽  
Michael A. Turner ◽  
Douglas Guss ◽  
Mark Lyng
Keyword(s):  
Organic Carbon ◽  
Water Chemistry ◽  
Experimental Manipulation ◽  
Low Ph ◽  
Chemical Mass Balance ◽  
Experimental Lakes Area ◽  
First Order ◽  
Mass Balance Models ◽  
Acidification And Recovery

Changes in climate, in particular significant changes in precipitation and evaporation and thus runoff, as well as changes in regional atmospheric deposition can affect the changes in chemical masses or concentrations in lakes. We have examined the changes in alkalinity, sulfate, and dissolved organic carbon (DOC) during a 20-year period when Lake 302S and Lake 302N at the Experimental Lakes Area (Ontario, Canada) were acidified with sulfuric, nitric, and hydrochloric acids and returned to natural pH. We used the corresponding 20-year history in Lake 239 to build chemical mass balance models for the experimental lakes. With these models, we assessed the production of alkalinity and the loss of sulfate and DOC in the context of atmospheric and watershed inputs and our experimental acid additions. Alkalinity production was greatest during the period of highest acid inputs and not detectable during pH recovery even in the early stages when pH was still low. Sulfate loss was also greatest while sulfate concentrations were increasing but counter to expectations not directly related to sulfate concentrations. Losses of the mass of DOC showed little change in response to acid additions over the 20 years, but first-order losses increased at low pH.

scholarly journals Modelling the effects of acid deposition: refinements, adjustments and inclusion of nitrogen dynamics in the MAGIC model

2001 ◽  
Vol 5 (3) ◽  
pp. 499-518 ◽  
Author(s):  
B. J. Cosby ◽  
R. C. Ferrier ◽  
A. Jenkins ◽  
R. F. Wright
Keyword(s):  
Acid Deposition ◽  
Acidic Deposition ◽  
Nitrogen Retention ◽  
Conceptual Structure ◽  
Nitrogen Dynamics ◽  
Model Structure ◽  
Short Term ◽  
Magic Model ◽  
Acidification And Recovery

Abstract. The MAGIC model of the responses of catchments to acidic deposition has been applied and tested extensively over a 15 year period at many sites and in many regions around the world. Overall, the model has proven to be robust, reliable and useful in a variety of scientific and managerial activities. Over the years, several refinements and additions to MAGIC have been proposed and/or implemented for particular applications. These adjustments to the model structure have all been included in a new version of the model (MAGIC7). The log aluminium – pH relationship now does not have to be fixed to aluminium trihydroxide solubility. Buffering by organic acids using a triprotic analog is now included. Dynamics of nitrogen retention and loss in catchments can now be linked to soil nitrogen and carbon pools. Simulation of short-term episodic response by mixing fractions of different water types is also possible. This paper presents a review of the conceptual structure of MAGIC7 relating to long-term simulation of acidification and recovery, describes the conceptual basis of the new nitrogen dynamics and provides a comprehensive update of the equations, variables, parameters and inputs for the model. Keywords: process-based model, acid deposition, recovery

Long-term studies (1871–2000) on acidification and recovery of lakes in the Bohemian Forest (central Europe)

2003 ◽  
Vol 310 (1-3) ◽  
pp. 73-85 ◽  
Author(s):  
Jaroslav Vrba ◽  
Jiřı&́ Kopáček ◽  
Jan Fott ◽  
Leoš Kohout ◽  
Linda Nedbalová ◽  
...  
Keyword(s):  
Central Europe ◽  
Bohemian Forest ◽  
The Bohemian Forest ◽  
Acidification And Recovery ◽  
Long Term Studies

Biogas production from mono-digestion of maize silage–long-term process stability and requirements

2008 ◽  
Vol 58 (8) ◽  
pp. 1645-1651 ◽  
Author(s):  
M. Lebuhn ◽  
F. Liu ◽  
H. Heuwinkel ◽  
A. Gronauer
Keyword(s):  
Biogas Production ◽  
Organic Loading Rate ◽  
Maize Silage ◽  
Process Failure ◽  
Reliable Parameter ◽  
Microbiological Parameters ◽  
Improved Stability ◽  
One Year ◽  
Acidification And Recovery

Biogas production from mono-digestion of maize silage was studied for more than one year in six continuously stirred, daily fed 36 L fermenters. Chemical and microbiological parameters were analysed concomitantly. The reactors acidified already after 8 months of operation at a low organic loading rate (OLR) of 2 g VS*(L*d)−1. The TVA/TAC ratio was the most reliable parameter to indicate early process instabilities leading to acidification. A TVA/TAC threshold of 0.5 should not be exceeded. After acidification and recovery of the fermenters, propionic acid was no reliable parameter anymore to indicate process failure, since values far below the threshold of 1 g*L−1 were obtained although the process had collapsed. The acidified reactors recovered better, showed greatly improved stability and allowed a higher OLR when a trace element (TE) cocktail was supplemented. Hydrolysis was obviously not process-limiting, results indicated that methanogens were affected. The most limiting element in long-term mono-digestion of maize silage turned out to be cobalt, but data obtained suggest that molybdenum and selenium should also be provided. TE supplementation should be designed specifically in order to meet the actual needs. TE availability for the biocenosis appears to be a key issue in biogas production, not only in mono-but also in co-digestion processes.

Therapy and prevention for mental health: What if mental diseases are mostly not brain disorders?

2019 ◽  
Vol 42 ◽  
Author(s):  
John P. A. Ioannidis
Keyword(s):  
Mental Health ◽  
Mental Disease ◽  
Brain Disorders ◽  
Social Stressors ◽  
Labor Education ◽  
Mental Diseases ◽  
Long Term Follow Up ◽  
Political Decisions

AbstractNeurobiology-based interventions for mental diseases and searches for useful biomarkers of treatment response have largely failed. Clinical trials should assess interventions related to environmental and social stressors, with long-term follow-up; social rather than biological endpoints; personalized outcomes; and suitable cluster, adaptive, and n-of-1 designs. Labor, education, financial, and other social/political decisions should be evaluated for their impacts on mental disease.

Conceptual short-term memory (CSTM) supports core claims of Christiansen and Chater

2016 ◽  
Vol 39 ◽  
Author(s):  
Mary C. Potter
Keyword(s):  
Working Memory ◽  
Rapid Serial Visual Presentation ◽  
Language Comprehension ◽  
Short Term Memory ◽  
Visual Presentation ◽  
Long Term Memory ◽  
Short Term ◽  
Term Memory ◽  
Use Of Knowledge

AbstractRapid serial visual presentation (RSVP) of words or pictured scenes provides evidence for a large-capacity conceptual short-term memory (CSTM) that momentarily provides rich associated material from long-term memory, permitting rapid chunking (Potter 1993; 2009; 2012). In perception of scenes as well as language comprehension, we make use of knowledge that briefly exceeds the supposed limits of working memory.

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