scholarly journals Trait-Based Models of Decomposition with Interspecific and Environmental Interactions

2021 ◽  
Vol 267 ◽  
pp. 02029
Author(s):  
SiYu Liu ◽  
RuiXi Wang ◽  
LuYao Dong
Keyword(s):  
Robustness Analysis ◽  
Grey System Theory ◽  
Niche Width ◽  
Extension Rate ◽  
Grey System ◽  
Advantages And Disadvantages ◽  
Environmental Interactions ◽  
Long Term Trends ◽  
The Impact

Most saprotrophic fungi are dominant decomposers, and they play a vital role in the carbon cycle and stability of ecosystem. Previous researchers examined that how traits and environments influence the decomposition rate(DR), but few studies last long enough to scale short-term results up to long-term trends. In this paper, we build several trait-based models of decomposition with interspecific and environmental interactions to describe both short- and long-term trends. First, we build the model of decomposition ratio versus time with covariates – hyphal extension ratio and moisture tolerance for each species. Second, we define Interspecific Interference Ratio (IIR) to reflect interactions between fungi species and rank the relative competitiveness based on Grey System Theory with four evaluation indices: hyphal extension rate, moisture niche width, the hyphal density and thermal niche width. Then, we predict the relative advantages and disadvantages for different species by IIR and analyze the impact of biodiversity. Finally, we perform sensitivity and robustness analysis of our models, which exhibits the wide prospects and a deeper understanding of the role of fungi in the ecosystem.

scholarly journals Spatial patterns of linear and nonparametric long-term trends in Baltic sea-level variability

2012 ◽  
Vol 19 (1) ◽  
pp. 95-111 ◽  
Author(s):  
R. V. Donner ◽  
R. Ehrcke ◽  
S. M. Barbosa ◽  
J. Wagner ◽  
J. F. Donges ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Sea Level ◽  
Spatial Patterns ◽  
Tide Gauge ◽  
Sufficient Information ◽  
Sea Level Variability ◽  
Advantages And Disadvantages ◽  
Long Term Trends ◽  
The Impact

Abstract. The study of long-term trends in tide gauge data is important for understanding the present and future risk of changes in sea-level variability for coastal zones, particularly with respect to the ongoing debate on climate change impacts. Traditionally, most corresponding analyses have exclusively focused on trends in mean sea-level. However, such studies are not able to provide sufficient information about changes in the full probability distribution (especially in the more extreme quantiles). As an alternative, in this paper we apply quantile regression (QR) for studying changes in arbitrary quantiles of sea-level variability. For this purpose, we chose two different QR approaches and discuss the advantages and disadvantages of different settings. In particular, traditional linear QR poses very restrictive assumptions that are often not met in reality. For monthly data from 47 tide gauges from along the Baltic Sea coast, the spatial patterns of quantile trends obtained in linear and nonparametric (spline-based) frameworks display marked differences, which need to be understood in order to fully assess the impact of future changes in sea-level variability on coastal areas. In general, QR demonstrates that the general variability of Baltic sea-level has increased over the last decades. Linear quantile trends estimated for sliding windows in time reveal a wide-spread acceleration of trends in the median, but only localised changes in the rates of changes in the lower and upper quantiles.

The impact of non-ideality on reconstructing spatial and temporal variations of aerosol acidity with multiphase buffer theory

2021 ◽  
Author(s):  
Yafang Cheng ◽  
Guangjie Zheng ◽  
Hang Su ◽  
Siwen Wang ◽  
Andrea Pozzer
Keyword(s):  
Molar Fraction ◽  
Temporal Variations ◽  
Spatial Variations ◽  
Acid Dissociation ◽  
Acid Dissociation Constant ◽  
Aerosol Acidity ◽  
Long Term Trends ◽  
Factor C ◽  
The Impact

<p>Aerosol acidity is a key parameter in atmospheric aqueous chemistry and strongly influence the interactions of air pollutants and ecosystem. The recently proposed multiphase buffer theory provides a framework to reconstruct long-term trends and spatial variations of aerosol pH based on the effective acid dissociation constant of ammonia (K<sub>a,NH3</sub><sup>*</sup>). However, non-ideality in aerosol droplets is a major challenge limiting its broad applications. Here, we introduced a non-ideality correction factor (c<sub>ni</sub>) and investigated its governing factors. We found that besides relative humidity (RH) and temperature, c<sub>ni</sub> is mainly determined by the molar fraction of NO<sub>3</sub><sup>-</sup> in aqueous-phase anions, due to different NH<sub>4</sub><sup>+</sup> activity coefficients between (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub>- and NH<sub>4</sub>NO<sub>3</sub>-dominated aerosols. A parameterization method is thus proposed to estimate c<sub>ni</sub> at given RH, temperature and NO<sub>3</sub><sup>-</sup> fraction, and is validated against long-term observations and global simulations. In the ammonia-buffered regime, with c<sub>ni</sub> correction the buffer theory can well reproduce the K<sub>a,NH3</sub><sup>*</sup> predicted by comprehensive thermodynamic models, with root-mean-square deviation ~0.1 and correlation coefficient ~1. Note that, while c<sub>ni</sub> is needed to predict K<sub>a,NH3</sub><sup>*</sup> levels, it is usually not the dominant contributor to its variations, as ~90% of the temporal or spatial variations in K<sub>a,NH3</sub><sup>*</sup> is due to variations in aerosol water and temperature.</p>

The Protection of Turkish Citizens Against Expulsion—This Far and No Further? The Impact of the Ziebell Case

2013 ◽  
Vol 14 (1) ◽  
pp. 239-267
Author(s):  
Kathrin Hamenstädt
Keyword(s):  
Case Law ◽  
Fundamental Rights ◽  
Association Agreement ◽  
Advantages And Disadvantages ◽  
Court Of Justice ◽  
Council Decision ◽  
European Court ◽  
The One ◽  
The Impact

This Article focuses on the Ziebell judgment, in which the European Court of Justice rejected the analogous application of the protection against expulsion for Union citizens to Turkish citizens covered by the Association Agreement. The judgment is placed in the context of the opinion of the Advocate General, the pre-Ziebell judgments of the Court, and judgments of German courts regarding the expulsion of Turkish citizens. On the one hand, against the background of previous case-law of the Court, the judgment might be seen as a setback. On the other hand, the Court's reference to the Long-Term Residents Directive also provides for new interpretative possibilities. Next to the applicability of the directive and the advantages and disadvantages for Turkish nationals triggered by this shift, the interpretative possibilities are discussed in light of fundamental rights and the stand-still obligation anchored in Association Council Decision 1/80.

A Novel Method to Improve the Accuracy of Grey Prediction Model in Economic Prediction

2013 ◽  
Vol 347-350 ◽  
pp. 3331-3335
Author(s):  
Qian Ru Wang ◽  
Xi Wei Chen ◽  
Da Shi Luo ◽  
Yu Feng Wei ◽  
Li Ya Jin ◽  
...  
Keyword(s):  
System Theory ◽  
Time Series Data ◽  
Grey System Theory ◽  
Series Data ◽  
Model Parameters ◽  
Economic Data ◽  
Grey System ◽  
Forecasting Accuracy ◽  
Highly Nonlinear ◽  
The Impact

Grey system theory has been widely used to forecast the economic data that are often highly nonlinear, irregular and non-stationary. Many models based on grey system theory could adapt to various economic time series data. However, some of these models didnt consider the impact of the model parameters, or only considered a simple change of the model parameters for the prediction. In this paper, we proposed the PSO based GM (1, 1) model using the optimized parameters in order to improve the forecasting accuracy. The experiment shows that PSO based GM (1, 1) gets much better forecasting accuracy compared with other widely used grey models on the actual chaotic economic data.

Evaluating the impact of ballast undercutting on the roughness of track geometry over different subgrade conditions

2017 ◽  
Vol 232 (5) ◽  
pp. 1266-1276
Author(s):  
Kirk M Scanlan ◽  
Michael T Hendry ◽  
C Derek Martin
Keyword(s):  
Surface Roughness ◽  
Organic Soils ◽  
Western Canada ◽  
Railway Ballast ◽  
Track Geometry ◽  
Track Maintenance ◽  
Heavy Haul ◽  
Long Term Trends ◽  
The Impact

The progressive degradation of railway ballast is often cited as a primary factor that contributes to the development of track roughness, while ballast renewal (undercutting) attempts to manage its long-term development. Soft subgrades have been shown to strongly influence track geometry and are a contributing factor that has not been considered during conventional track maintenance. This study evaluated the impact of undercutting on long-term trends in track geometry roughness, and what impact softer subgrades had on the effectiveness of undercutting. A combined 6.90 km of Class II–IV heavy-haul track in Western Canada (undercut in 2010 and 2011) formed the basis for this analysis. Annual traffic on these sections typically totals 50 million gross tonnes. Long-term trends in the track crosslevel, alignment, and surface roughness after ballast renewal were derived from 50 track geometry surveys carried out over a five-year period (2010–2015). The results showed that undercutting significantly reduced track roughness over sand, silt, clay, or till subgrades; however, it was often ineffective when used over soft organic subgrades. Thus, while ballast degradation is the primary cause of track roughness in segments constructed on mineral subgrades, it is not a mechanism that results in track geometry roughness over soft organic soils.

scholarly journals The Impact of Improved Thermistor Calibration on the Expendable Bathythermograph Profile Data

2017 ◽  
Vol 34 (9) ◽  
pp. 1947-1961 ◽  
Author(s):  
Marlos Goes ◽  
Elizabeth Babcock ◽  
Francis Bringas ◽  
Peter Ortner ◽  
Gustavo Goni
Keyword(s):  
Small Sample Size ◽  
Heat Content ◽  
Small Sample ◽  
Profile Data ◽  
Expendable Bathythermograph ◽  
Different Types ◽  
Long Term Trends ◽  
The Mean ◽  
The Impact

AbstractExpendable bathythermograph (XBT) data provide one of the longest available records of upper-ocean temperature. However, temperature and depth biases in XBT data adversely affect estimates of long-term trends of ocean heat content and, to a lesser extent, estimates of volume and heat transport in the ocean. Several corrections have been proposed to overcome historical biases in XBT data, which rely on constantly monitoring these biases. This paper provides an analysis of data collected during three recent hydrographic cruises that utilized different types of probes, and examines methods to reduce temperature and depth biases by improving the thermistor calibration and reducing the mass variability of the XBT probes.The results obtained show that the use of individual thermistor calibration in XBT probes is the most effective calibration to decrease the thermal bias, improving the mean thermal bias to less than 0.02°C and its tolerance from 0.1° to 0.03°C. The temperature variance of probes with screened thermistors is significantly reduced by approximately 60% in comparison to standard probes. On the other hand, probes with a tighter weight tolerance did not show statistically significant reductions in the spread of depth biases, possibly because of the small sample size or the sensitivity of the depth accuracy to other causes affecting the analysis.

scholarly journals A comparison of fertility control and lethal control of bovine tuberculosis in badgers: the impact of perturbation induced transmission

1997 ◽  
Vol 352 (1353) ◽  
pp. 619-631 ◽  
Author(s):  
J. Swinton ◽  
F. Tuyttens ◽  
D. Macdonald ◽  
D. J. Nokes ◽  
C. L. Cheeseman ◽  
...  
Keyword(s):  
Bovine Tuberculosis ◽  
Fertility Control ◽  
Transmission Model ◽  
Infection Prevalence ◽  
Lethal Control ◽  
Advantages And Disadvantages ◽  
Contact Rates ◽  
Age Cohort ◽  
The Impact

In this paper we use mathematical modelling to consider the broad advantages and disadvantages of fertility control over lethal control for bovine tuberculosis in badger populations. We use a deliberately simple model, attempting to capture only the key transmission processes. The model is parametrized with reference to the long–term Woodchester Park study. Estimates of mortality rate from this study suggest no significant extra mortality risk for animals with evidence of infection as indicated by the presence of anti- Mycobacterium bovis antibodies or M. bovis isolation. We find that large reductions in prevalence are sometimes the consequence of only moderate reductions in population numbers. If we assume that the act of control does not in itself affect transmission rates, then as far as eradication is concerned, both fertility control and mortality control operate through the same epidemiological mechanism, the removal of susceptibles: if one is in principle capable of keeping a population low enough to be infection free then so is the other. It is necessary to continue either form of control at regular intervals to maintain a constant level of infection in the long term. If control were to be stopped, return to precontrol levels of badger population and infection prevalence would be expected within a few years. Fertility control is less effective in reducing population density than lethal control since it can only act, at maximum, to remove one age cohort per year. It is also less effective in reducing transmission as it can only ever remove susceptibles, while lethal control also removes infectious badgers. However, if the social disturbance caused by lethal control does in fact increase contact rates for the remaining infectious badgers, the relative efficacies of the two strategies become a great deal less clear. While we have no quantitative data on the extent to which social perturbation does act to promote transmission, model simulations show that it is possible to develop plausible scenarios in which the lethal control may actually act to increase the absolute numbers of animals infected, while reducing the number of uninfected animals to very low numbers.

scholarly journals The Impact of Non-uniform Sampling on Stratospheric Ozone Trends Derived from Occultation Instruments

2017 ◽  
Author(s):  
Robert P. Damadeo ◽  
Joseph M. Zawodny ◽  
Ellis E. Remsberg ◽  
Kaley A. Walker
Keyword(s):  
Stratospheric Ozone ◽  
Primary Source ◽  
Data Sets ◽  
Sampled Data ◽  
Uniform Sampling ◽  
Ozone Trends ◽  
Long Term Trends ◽  
Non Uniform Sampling ◽  
The Impact

Abstract. This paper applies a recently developed technique for deriving long-term trends in ozone from sparsely sampled data sets to multiple occultation instruments simultaneously without the need for homogenization. The technique can compensate for the non-uniform temporal, spatial, and diurnal sampling of the different instruments and can also be used to account for biases and drifts between instruments. These problems have been noted in recent international assessments as being a primary source of uncertainty that clouds the significance of derived trends. Results show potential recovery trends of ~ 2–3 %/decade in the upper stratosphere at mid-latitudes, which are similar to other studies, and also how sampling biases present in these data sets can create differences in derived "recovery" trends of up to ~ 1 %/decade if not properly accounted for. Limitations inherent to all techniques (e.g., relative instrument drifts) and their impacts (e.g., trend differences up to ~ 2 %/decade) are also described and a potential path forward towards resolution is presented.

scholarly journals Investigation of the impact of the project office on the socio-economic development of the municipality

2021 ◽  
Vol 12 (1) ◽  
pp. 157-172
Author(s):  
Alla Yu. Trusova ◽  
Vladimir I. Aksenov
Keyword(s):  
Economic Development ◽  
Development Strategy ◽  
Scientific Article ◽  
Management Tools ◽  
Project Approach ◽  
Regional Development Strategy ◽  
Socio Economic Development ◽  
Long Term Trends ◽  
The Impact

The complexity of the socio-economic situation at all levels requires a detailed study of the regional development strategy issues and monitoring the implementation of presidential and government decrees. Various approaches to management were considered, for example, the national projects development implementation issues. National projecting, as a new tool for implementing state concepts, is an effective management method. The set of the project office functions provides control over the implementation of national projects at the level of development of municipalities of the Russian Federation. Historically, the level of socio-economic development of the territory has been measured and is measured using the identification of long-term trends in the development of key socio-economic indicators. The article presents a methodology that allows you to evaluate the effectiveness of project management tools since based on the results of its assessment, you can make informed management decisions and judge the effectiveness of the work of local authorities. Therefore, the aim of the scientific article was to develop an effective methodology that allows us to evaluate the effectiveness of the project office functions implemented in the management of the socio-economic development of the municipality. As a result of the study, systemic relationships were revealed of the impact of the project office on the indicators of the socio-economic development of the municipality, which was presented in the work as an important aspect of the study, the significance of which is due to the priorities of sustainable, balanced, competitive, integrated development of the Russian regions. In connection with the socio-economic policy pursued by the state, which requires speedy acceleration of the socio-economic development of municipalities, the effectiveness of the result of the application of the project approach in the municipal authorities was studied in detail.

scholarly journals Resilience to childhood adversity

2016 ◽  
Vol 85 (2) ◽  
pp. 22-25
Author(s):  
Catherine Anne Wassenaar
Keyword(s):  
Childhood Adversity ◽  
Later Life ◽  
Environmental Research ◽  
Post Traumatic Stress ◽  
Gene Coding ◽  
Environmental Interactions ◽  
Mitigating Factor ◽  
High Degree ◽  
The Impact

Despite being linked to several negative long-term physical and psychological pathologies in adulthood, childhood adversity elicits variable responses in the sufferer. When searching for explanations for this heterogeneity, the concept of resilience has been postulated as a potential mitigating factor. Gene-environmental interactions are a promising avenue in the study of resilience. The premise of gene-environmental research is that interindividual variability in the response to an environmental stressor is due to an individual’s genetic make-up exacerbating or buffering the impact of that stressor. Herein, gene-environmental findings are illustrated in the context of depression and post-traumatic stress disorder (PTSD). Many of the gene loci found to interact with childhood adversity influence both depression and PTSD possibly due to the high degree of shared heritability between these psychopathologies. Variation in the serotonin transporter gene, SLC6A4, and in FKBP5, a gene coding for a glucocorticoid receptor binding protein, interacts with childhood adversity to influence the development and symptomology of depression and of PTSD. Findings in the field of gene-environmental interactions has led to a proposed 3-hit model whereby 3 hits, genetics, early life experiences and later life stressors, interact to determine whether an individual is vulnerable or resilient to the development of psychopathology. As limitations with the current research are addressed and complementary lines of research are integrated, the insight gained on childhood adversity has the potential to better predict children at risk of the long-term sequelae of adversity and to inform potential intervention and prevention strategies.

Sign in / Sign up

Export Citation Format

Share Document