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- Laouali, D., et al.
(author)
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Source contributions in precipitation chemistry and analysis of atmospheric nitrogen deposition in a Sahelian dry savanna site in West Africa
- 2021
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In: Atmospheric Research. - : Elsevier BV. - 0169-8095. ; 251
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Journal article (peer-reviewed)abstract
- Experimental data on precipitation chemistry were collected at a semi-arid savanna in Senegal (Dahra) in 2013, 2014 and 2017. The chemical composition of precipitation was analyzed for inorganic and organic ions, using ionic chromatography. The pH values of precipitation range from 4.50 to 8.50 with 89% of the samples having basic pH. The composition of precipitation was controlled by four source contributions: marine, terrigenous, biogenic, and organic acids emissions from vegetation. The terrigenous contribution was the highest accounting for 42% of the total annual Volume Weighted Mean ionic concentrations, due to the proximity of the Saharan desert, followed by the marine source representing 36%, due to the location of Dahra close to the Atlantic Ocean. Nitrogenous (N) contribution represents 16% of the mean annual total ionic charge, from biogenic sources and livestock crossing the site all year round. Finally, the lowest contribution is from organic acidity (5%), due to the low density of vegetation especially during the dry season. Wet deposition fluxes in Dahra for all compounds show larger values than at other Sahelian savanna sites. Dry N deposition in Dahra was also estimated by inferential method using gas concentration measurements and modeled dry deposition velocities. The total N deposition fluxes (wet plus dry) range from 3.80 to 4.81 kgN ha−1 yr−1, comparable to fluxes at other semi-arid savannas in Niger and Mali. Wet deposition contributed with 37–53% of the total N flux, suggesting that wet N deposition is equally important to dry deposition fluxes for direct N loading to savanna ecosystems in the Sahel, with a large contribution of reduced compounds. This study shows that Dahra presents a precipitation chemistry composition with characteristics close to those from other Sahelian sites, with however the specificity of being more influenced by the proximity of the Atlantic ocean and the presence of livestock year round.
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| 2. |
- Martínez, Beatriz, et al.
(author)
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Evaluation of the LSA-SAF Gross Primary Production product derived from SEVIRI/MSG data (MGPP)
- 2020
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In: ISPRS Journal of Photogrammetry and Remote Sensing. - : Elsevier BV. - 0924-2716. ; 159, s. 220-236
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Journal article (peer-reviewed)abstract
- The objective of this study is to describe a completely new 10-day gross primary production (GPP) product(MGPP LSA-411) based on data from the geostationary SEVIRI/MSG satellite within the LSA SAF (Land SurfaceAnalysis SAF) as part of the SAF (Satellite Application Facility) network of EUMETSAT.The methodology relies on the Monteith approach. It considers that GPP is proportional to the absorbedphotosynthetically active radiation APAR and the proportionality factor is known as the light use efficiency ε. Aparameterization of this factor is proposed as the product of a εmax, corresponding to the canopy functioningunder optimal conditions, and a coefficient quantifying the reduction of photosynthesis as a consequence ofwater stress. A three years data record (2015–2017) was used in an assessment against site-level eddy covariance(EC) tower GPP estimates and against other Earth Observation (EO) based GPP products. The site-level comparisonindicated that the MGPP product performed better than the other EO based GPP products with 48% ofthe observations being below the optimal accuracy (absolute error < 1.0 g m−2 day−1) and 75% of these databeing below the user requirement threshold (absolute error < 3.0 g m−2 day−1). The largest discrepanciesbetween the MGPP product and the other GPP products were found for forests whereas small differences wereobserved for the other land cover types. The integration of this GPP product with the ensemble of LSA-SAF MSG
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| 3. |
- Uman, Timur, 1981-, et al.
(author)
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Exploring the antecedents of the mental health of business professionals in Sweden
- 2020
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In: Work. - : IOS Press. - 1051-9815 .- 1875-9270. ; 67:3, s. 665-669
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Journal article (peer-reviewed)abstract
- BACKGROUND: Business professionals are an important occupational group that carries responsibility for the economic welfare of organizations and of society at large. These professionals have recently been reported to be experiencing increased mental strain, which may have a significant effect on the role they play in organizations and in society. Understanding the causes of this strain is thus an important endeavour.OBJECTIVE: This study explores the antecedents of the mental health of business professionals.METHODS: Multiple linear regression analyses were used to examine the relationship between business professionals' mental health and its demographic, work-related, and other triggers. T-tests and descriptive statistics were used to explore the gender of the respondents in relation to these triggers and mental health.RESULTS: Compared with their male counterparts, female business professionals report poorer mental health; however, no gender differences were found in job satisfaction or life satisfaction. According to this study, age, overtime pay, higher salary and position as a manager have a positive relation with mental health, whereas working overtime has a negative relation with mental health. Job satisfaction and life satisfaction are important determinants of the mental health of business professionals.CONCLUSIONS: Business professionals are important to the economic welfare of their organization and of society as a whole. Our study suggests that demographic characteristics, work-related aspects and subjective dimensions of well-being have a profound effect on the mental health of business professionals.
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