scholarly journals An unusual kind of diurnal streamflow variation

2018 ◽  
Vol 66 (1) ◽  
pp. 32-42
Author(s):  
Jaime G. Cuevas ◽  
José L. Arumí ◽  
Alejandra Zúñiga-Feest ◽  
Christian Little
Keyword(s):  
Positive Relationship ◽  
Landscape Heterogeneity ◽  
Control Point ◽  
Growing Season ◽  
Early Morning ◽  
Rain Event ◽  
Mountain Forests ◽  
Signal Delay ◽  
Swamp Forest

Abstract During hydrological research in a Chilean swamp forest, we noted a pattern of higher streamflows close to midday and lower ones close to midnight, the opposite of an evapotranspiration (Et)-driven cycle. We analyzed this diurnal streamflow signal (DSS), which appeared mid-spring (in the growing season). The end of this DSS coincided with a sustained rain event in autumn, which deeply affected stream and meteorological variables. A survey along the stream revealed that the DSS maximum and minimum values appeared 6 and 4 hours earlier, respectively, at headwaters located in the mountain forests/ plantations than at the control point in the swamp forest. Et in the swamp forest was higher in the morning and in the late afternoon, but this process could not influence the groundwater stage. Trees in the mountain headwaters reached their maximum Ets in the early morning and/or close to midday. Our results suggest that the DSS is a wave that moves from forests high in the mountains towards lowland areas, where Et is decoupled from the DSS. This signal delay seems to convert the link between streamflow and Et in an apparent, but spurious positive relationship. It also highlights the role of landscape heterogeneity in shaping hydrological processes.

scholarly journals Ecological Connectivity in Agricultural Green Infrastructure:  Suggested Criteria for Fine Scale Assessment and Planning

Land ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 807
Author(s):  
Simone Valeri ◽  
Laura Zavattero ◽  
Giulia Capotorti
Keyword(s):  
Land Cover ◽  
Green Infrastructure ◽  
Rural Areas ◽  
Urban Areas ◽  
Landscape Heterogeneity ◽  
Agricultural Landscapes ◽  
Spatial Pattern Analysis ◽  
Fine Scale ◽  
Unique Type

In promoting biodiversity conservation and ecosystem service capacity, landscape connectivity is considered a critical feature to counteract the negative effects of fragmentation. Under a Green Infrastructure (GI) perspective, this is especially true in rural and peri-urban areas where a high degree of connectivity may be associated with the enhancement of agriculture multifunctionality and sustainability. With respect to GI planning and connectivity assessment, the role of dispersal traits of tree species is gaining increasing attention. However, little evidence is available on how to select plant species to be primarily favored, as well as on the role of landscape heterogeneity and habitat quality in driving the dispersal success. The present work is aimed at suggesting a methodological approach for addressing these knowledge gaps, at fine scales and for peri-urban agricultural landscapes, by means of a case study in the Metropolitan City of Rome. The study area was stratified into Environmental Units, each supporting a unique type of Potential Natural Vegetation (PNV), and a multi-step procedure was designed for setting priorities aimed at enhancing connectivity. First, GI components were defined based on the selection of the target species to be supported, on a fine scale land cover mapping and on the assessment of land cover type naturalness. Second, the study area was characterized by a Morphological Spatial Pattern Analysis (MSPA) and connectivity was assessed by Number of Components (NC) and functional connectivity metrics. Third, conservation and restoration measures have been prioritized and statistically validated. Notwithstanding the recognized limits, the approach proved to be functional in the considered context and at the adopted level of detail. Therefore, it could give useful methodological hints for the requalification of transitional urban–rural areas and for the achievement of related sustainable development goals in metropolitan regions.

An experimental approach to communal coping

2021 ◽  
pp. 026540752199246
Author(s):  
Melissa Zajdel ◽  
Vicki S. Helgeson
Keyword(s):  
Health Outcomes ◽  
Positive Relationship ◽  
Experimental Approach ◽  
Positive Mood ◽  
Self Report ◽  
Communal Coping ◽  
Observational Measures ◽  
Relationship Outcomes ◽  
The Individual

Communal coping has been linked to better psychological and physical health across a variety of stressful contexts. However, there has been no experimental work causally linking communal coping to relationship and health outcomes. In addition, research has emphasized the collaboration over the shared appraisal component of communal coping. The present study sought to isolate the role of appraisal by manipulating whether dyads viewed a stressor as shared or individual. Friend dyads (n = 64 dyads; 128 participants) were randomly assigned to view a stressor as either a shared or an individual problem, but both groups were allowed to work together. Across self-report and observational measures dyads reported more collaboration and support, better relationship outcomes, and more positive mood after the stressor in the shared than the individual appraisal group. This is the first laboratory evidence to establish causal links of communal coping—specifically shared appraisal—to positive relationship and health outcomes.

Kaolin impacts on hormonal balance, polyphenolic composition and oenological parameters in red grapevine berries during ripening

2021 ◽  
pp. 1-15
Author(s):  
Sara Bernardo ◽  
Lia-Tânia Dinis ◽  
Nelson Machado ◽  
Ana Barros ◽  
Marta Pitarch-Bielsa ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Growing Season ◽  
Growing Seasons ◽  
Polyphenolic Composition ◽  
Berry Ripening ◽  
Hormonal Balance ◽  
Summer Stress ◽  
Fruit Damage ◽  
Stress Signals

BACKGROUND: Kaolin particle-film application is a well-known strategy to avoid fruit damage. However, its putative role in balancing berry ripening under a changing climate remains poorly explored. OBJECTIVE: We assessed kaolin treatment effect on several ripening berry components, hormonal balance and oenological parameters of the field-grown Touriga-Franca (TF) and Touriga–Nacional (TN) grapevine varieties at veraison (EL35) and ripening (EL38) during two growing seasons (2017 and 2018). RESULTS: Under the adverse summer conditions (two heatwave events) of 2017, kaolin application increased 211.2 %and 51.4 %the salicylic acid (SA) and abscisic acid (ABA) levels in TF berries at EL38, while no significant differences were observed in TN. Conversely, TF, and TN kaolin treated berries showed lower SA and ABA accumulation in 2018, respectively. Tartaric acid content increased about 17.2 %, and 24.2 %in TF and TN treated berries at stage EL35 in the 2017 growing season. Though kaolin treatment had no consistent effect on anthocyanins accumulation, flavonoids, ortho-diphenols and tannins increased in kaolin treated grapevines in 2017. CONCLUSIONS: This study highlights the key role of climate in triggering ripening related processes and fruit quality potential. Nevertheless, kaolin treated grapevines displayed an improved response to oxidative stress signals by increasing secondary metabolites accumulation in warm vintages. Kaolin application promoted different varietal responses, with a possible ripening delaying effect in TF, reinforcing its efficiency in alleviating severe summer stress impacts.

Accounting Conservatism and Firm Growth Financed by External Debt

2016 ◽  
Vol 32 (2) ◽  
pp. 182-208 ◽  
Author(s):  
Tony Kang ◽  
Gerald J. Lobo ◽  
Michael C. Wolfe
Keyword(s):  
Firm Growth ◽  
Positive Relationship ◽  
External Debt ◽  
Debt Maturity ◽  
Accounting Conservatism ◽  
Debt Contracting ◽  
Conservative Accounting ◽  
Agency Risk

Previous research shows that accounting conservatism facilitates debt contracting. Extending this line of literature, we examine whether the role of accounting conservatism in accessing external debt to attain firm growth varies with its maturity. We find evidence of a positive relationship between conservatism and debt maturity. We also observe a positive relationship between conservative accounting and future growth funded by all classes of debt, but this relation is due to long-term rather than short-term debt, which is less prone to agency risk. Furthermore, the associations between conservatism and debt maturity and conservatism and growth financed by long-term debt are mostly observed for firms with fewer anti-takeover provisions in place. These findings suggest that the demand for accounting conservatism is not uniform across different debt maturity horizons.

Career Plateau and Turnover Intention in Chinese Employees: Career Anchor as Moderator

2015 ◽  
Vol 43 (5) ◽  
pp. 757-766 ◽  
Author(s):  
Yueran Wen ◽  
Liu Liu
Keyword(s):  
Turnover Intention ◽  
Positive Relationship ◽  
Management Practices ◽  
Career Anchor ◽  
Career Plateau ◽  
Strong Positive Relationship ◽  
High Level ◽  
The Relationship ◽  
Moderating Role

Based on a survey of 147 Chinese employees, we examined the relationship between perceived career plateau and turnover intention, and the moderating role of career anchor in challenge in this process. We hypothesized that perceived career plateau would be positively related to turnover intention, and that this relationship would be stronger in employees with a higher level of career anchor in challenge than in those with a lower level. The results showed that perceived career plateau had a strong positive relationship with turnover intention, especially in employees with a high level of career anchor in challenge. These findings have implications for research in career development and turnover intention, as well as in management practices.

An island biogeography model for beta diversity and endemism: The roles of speciation, extinction and dispersal

2015 ◽  
Vol 08 (01) ◽  
pp. 1550011 ◽  
Author(s):  
Youhua Chen
Keyword(s):  
Numerical Simulation ◽  
Community Composition ◽  
Beta Diversity ◽  
Island Biogeography ◽  
Positive Relationship ◽  
Community Patterns ◽  
Speciation Rate ◽  
Immigration Rate ◽  
Extinction Rates

A community composition island biogeography model was developed to explain and predict two community patterns (beta diversity and endemism) with the consideration of speciation, extinction and dispersal processes. Results showed that rate of speciation is positively and linearly associated with beta diversity and endemism, that is, increasing species rates typically could increase the percentage of both endemism and beta diversity. The influences of immigration and extinction rates on beta diversity and endemism are nonlinear, but with numerical simulation, I could observe that increasing extinction rates would lead to decreasing percentage of endemism and beta diversity. The role of immigration rate is very similar to that of speciation rate, having a positive relationship with beta diversity and endemism. Finally, I found that beta diversity is closely related to the percentage of endemism. The slope of this positive relationship is determined jointly by different combinations of speciation, extinction and immigration rates.

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