scholarly journals Hydrology under change: long-term annual and seasonal changes in small agricultural catchments in Norway

2021 ◽  
Author(s):  
Hannah Wenng ◽  
Danny Croghan ◽  
Marianne Bechmann ◽  
Hannu Marttila
Keyword(s):  
Seasonal Changes ◽  
Snow Water Equivalent ◽  
Ecological Status ◽  
Nutrient Loss ◽  
Wavelet Coherence ◽  
Soil Water Storage ◽  
Agricultural Catchments ◽  
Wavelet Coherence Analysis ◽  
Hydrological Regimes

Abstract In agricultural catchments, hydrological processes are highly linked to particle and nutrient loss and can lead to a degradation of the ecological status of the water. Global warming and land use changes influence the hydrological regime. This effect is especially strong in cold regions. In this study, we used long-term hydrological monitoring data (22–26 years) from small agricultural catchments in Norway. We applied a Mann–Kendall trend and wavelet coherence analysis to detect annual and seasonal changes and to evaluate the coupling between runoff, climate, and water sources. The trend analysis showed a significant increase in the annual and seasonal mean air temperature. In all sites, hydrological changes were more difficult to detect. Discharge increased in autumn and winter, but this trend did not hold for all catchments. We found a strong coherence between discharge and precipitation, between discharge and snow water equivalent and discharge and soil water storage capacity. We detected different hydrological regimes of rain and snow-dominated catchments. The catchments responded differently to changes due to their location and inherent characteristics. Our results highlight the importance of studying local annual and seasonal changes in hydrological regimes to understand the effect of climate and the importance for site-specific management plans.

Effect of economic indicators, biomass energy on human development in China

2021 ◽  
pp. 0958305X2110220
Author(s):  
Ngo Thai Hung
Keyword(s):  
Human Development ◽  
Global Financial Crisis ◽  
Trade Openness ◽  
Biomass Energy ◽  
Wavelet Coherence ◽  
Causality Test ◽  
Frequency Domains ◽  
Bidirectional Relationship ◽  
The Global Financial Crisis

Previous studies ignored the distinction between short, medium, and long term by decomposing macroeconomic variables and human development index at different time scales. We re-visit the causal association between biomass energy (BIO), economic growth (GDP), trade openness (TRO), industrialization (IND), foreign direct investment (FDI), and human development (HDI) in China on a quarterly scale by scale basis for the period 1990 to 2019 using the tools of wavelet, i.e., wavelet correlation, wavelet coherence and scale by scale Granger causality test. The main findings uncover that IND, TRO, GDP, and BIO positively drive the HDI at low and medium frequencies, while FDI negatively impacts HDI during the sample period. Additionally, there is a bidirectional relationship between GDP and HDI at different time and frequency domains. Specifically, we discover that the positive co-movement is more robust in the aftermath of the global financial crisis, particularly for HDI, BIO, GDP, and TRO at medium frequencies throughout the period under research. Our empirical insights have significant implications for achieving human development sustainability in China.

scholarly journals Can Long-Term Experiments Predict Real Field N and P Balance and System Sustainability? Results from Maize, Winter Wheat, and Soybean Trials Using Mineral and Organic Fertilisers

Agronomy ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1472
Author(s):  
Ilaria Piccoli ◽  
Felice Sartori ◽  
Riccardo Polese ◽  
Maurizio Borin ◽  
Antonio Berti
Keyword(s):  
Winter Wheat ◽  
Nutrient Balance ◽  
Environmental Indicators ◽  
Nutrient Loss ◽  
Real Field ◽  
Short Term ◽  
Organic Fertiliser ◽  
Long Term Experiments ◽  
P Balance

Agri-environmental indicators such as nutrient balance may play a key role in soil and water quality monitoring, although short-term experiments might be unable to capture the sustainability of cropping systems. Therefore, the objectives of this study are: (i) to evaluate the reliability of long-term experimental N and P balance estimates to predict real field (RF) (i.e., short-term transitory) conditions; and (ii) to compare the sustainability of short- and long-term experiments. The LTE-based predictions showed that crops are generally over-fertilised in RF conditions, particularly maize. Nutrient balance predictions based on the LTE data tended to be more optimistic than those observed under RF conditions, which are often characterised by lower outputs; in particular, 13, 44, and 47% lower yields were observed for winter wheat, maize, and soybean, respectively, under organic management. The graphical evaluation of N and P use efficiency demonstrated the benefit of adopting crop rotation practices and the risk of nutrient loss when liquid organic fertiliser was applied on a long-term basis. In conclusion, LTE predictions may depend upon specific RF conditions, representing potential N and P use efficiencies that, in RF, may be reduced by crop yield-limiting factors and the specific implemented crop sequence.

scholarly journals Thalamocortical Connectivity in Experimentally-Induced Migraine Attacks: A Pilot Study

2021 ◽  
Vol 11 (2) ◽  
pp. 165
Author(s):  
Daniele Martinelli ◽  
Gloria Castellazzi ◽  
Roberto De Icco ◽  
Ana Bacila ◽  
Marta Allena ◽  
...  
Keyword(s):  
Disease Model ◽  
Episodic Migraine ◽  
Wavelet Coherence ◽  
Test Time ◽  
Prodromal Phase ◽  
Brain Changes ◽  
The Right ◽  
Wavelet Coherence Analysis ◽  
Thalamic Function ◽  
Experimentally Induced

In this study we used nitroglycerin (NTG)-induced migraine attacks as a translational human disease model. Static and dynamic functional connectivity (FC) analyses were applied to study the associated functional brain changes. A spontaneous migraine-like attack was induced in five episodic migraine (EM) patients using a NTG challenge. Four task-free functional magnetic resonance imaging (fMRI) scans were acquired over the study: baseline, prodromal, full-blown, and recovery. Seed-based correlation analysis (SCA) was applied to fMRI data to assess static FC changes between the thalamus and the rest of the brain. Wavelet coherence analysis (WCA) was applied to test time-varying phase-coherence changes between the thalamus and salience networks (SNs). SCA results showed significantly FC changes between the right thalamus and areas involved in the pain circuits (insula, pons, cerebellum) during the prodromal phase, reaching its maximal alteration during the full-blown phase. WCA showed instead a loss of synchronisation between thalami and SN, mainly occurring during the prodrome and full-blown phases. These findings further support the idea that a temporal change in thalamic function occurs over the experimentally induced phases of NTG-induced headache in migraine patients. Correlation of FC changes with true clinical phases in spontaneous migraine would validate the utility of this model.

Wavelet coherence analysis of prefrontal oxygenation signals in elderly subjects with hypertension

2014 ◽  
Vol 35 (5) ◽  
pp. 777-791 ◽  
Author(s):  
Zengyong Li ◽  
Ming Zhang ◽  
Ruofei Cui ◽  
Qing Xin ◽  
Lu Liqian ◽  
...  
Keyword(s):  
Wavelet Coherence ◽  
Elderly Subjects ◽  
Coherence Analysis ◽  
Wavelet Coherence Analysis
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