scholarly journals Geographic distribution of tree species diversity of the United States reveals positive association between biodiversity and site productivity

2014 ◽  
Author(s):  
James V. Watson
Keyword(s):  
United States ◽  
Species Diversity ◽  
Geographic Distribution ◽  
Tree Species ◽  
Positive Association ◽  
The United States ◽  
Tree Species Diversity ◽  
Site Productivity

scholarly journals Mycorrhizal dominance reduces forest-tree species diversity

2021 ◽  
Author(s):  
Alexis Carteron ◽  
Mark Vellend ◽  
Etienne Laliberté
Keyword(s):  
Species Diversity ◽  
Tree Species ◽  
Species Coexistence ◽  
Seedling Recruitment ◽  
Arbuscular Mycorrhizal ◽  
The United States ◽  
Forest Tree ◽  
Arbuscular Mycorrhizas ◽  
Tree Diversity ◽  
Tree Species Diversity

SUMMARYEctomycorrhizas and arbuscular mycorrhizas, the two most widespread plant-fungal symbioses, are thought to differentially influence tree species diversity, with positive plant-soil feedbacks favoring locally abundant ectomycorrhizal tree species and negative feedbacks promoting species coexistence and diversity in arbuscular mycorrhizal forests. While seedling recruitment studies and cross-biome patterns of plant diversity and mycorrhizal dominance support this hypothesis, it remains to be tested at the forest stand level over continental scales. Here, we analyze ∼85,000 forest plots across the United States to show that both ectomycorrhizal-dominated and arbuscular mycorrhizal-dominated forests show relatively low tree diversity, while forests with a mixture of mycorrhizal strategies support a higher number of tree species. Our findings suggest that mycorrhizal dominance, rather than mycorrhizal type, shapes tree diversity in forests.

scholarly journals Tree Species Diversity, Composition and Aboveground Biomass Across Dry Forest Land-Cover Types in Coastal Ecuador

2021 ◽  
Vol 14 ◽  
pp. 194008292199541
Author(s):  
Xavier Haro-Carrión ◽  
Bette Loiselle ◽  
Francis E. Putz
Keyword(s):  
Species Diversity ◽  
Land Cover ◽  
Community Composition ◽  
Aboveground Biomass ◽  
Tree Species ◽  
Dry Forest ◽  
Stem Density ◽  
Tree Species Diversity ◽  
Land Cover Types ◽  
Schizolobium Parahyba

Tropical dry forests (TDF) are highly threatened ecosystems that are often fragmented due to land-cover change. Using plot inventories, we analyzed tree species diversity, community composition and aboveground biomass patterns across mature (MF) and secondary forests of about 25 years since cattle ranching ceased (SF), 10–20-year-old plantations (PL), and pastures in a TDF landscape in Ecuador. Tree diversity was highest in MF followed by SF, pastures and PL, but many endemic and endangered species occurred in both MF and SF, which demonstrates the importance of SF for species conservation. Stem density was higher in PL, followed by SF, MF and pastures. Community composition differed between MF and SF due to the presence of different specialist species. Some SF specialists also occurred in pastures, and all species found in pastures were also recorded in SF indicating a resemblance between these two land-cover types even after 25 years of succession. Aboveground biomass was highest in MF, but SF and Tectona grandis PL exhibited similar numbers followed by Schizolobium parahyba PL, Ochroma pyramidale PL and pastures. These findings indicate that although species-poor, some PL equal or surpass SF in aboveground biomass, which highlights the critical importance of incorporating biodiversity, among other ecosystem services, to carbon sequestration initiatives. This research contributes to understanding biodiversity conservation across a mosaic of land-cover types in a TDF landscape.

scholarly journals Household COVID-19 risk and in-person schooling

Science ◽  
2021 ◽  
pp. eabh2939
Author(s):  
Justin Lessler ◽  
M. Kate Grabowski ◽  
Kyra H. Grantz ◽  
Elena Badillo-Goicoechea ◽  
C. Jessica E. Metcalf ◽  
...  
Keyword(s):  
United States ◽  
Online Survey ◽  
Positive Association ◽  
The United States ◽  
Mitigation Measures ◽  
Office Work ◽  
School Based ◽  
Increased Risk ◽  
Extra Curricular Activities ◽  
Low Levels

In-person schooling has proved contentious and difficult to study throughout the SARS-CoV-2 pandemic. Data from a massive online survey in the United States indicates an increased risk of COVID-19-related outcomes among respondents living with a child attending school in-person. School-based mitigation measures are associated with significant reductions in risk, particularly daily symptoms screens, teacher masking, and closure of extra-curricular activities. A positive association between in-person schooling and COVID-19 outcomes persists at low levels of mitigation, but when seven or more mitigation measures are reported, a significant relationship is no longer observed. Among teachers, working outside the home was associated with an increase in COVID-19-related outcomes, but this association is similar to other occupations (e.g., healthcare, office work). While in-person schooling is associated with household COVID-19 risk, this risk can likely be controlled with properly implemented school-based mitigation measures.

scholarly journals Sport Spectatorship and Life Satisfaction: A Multicountry Investigation

2017 ◽  
Vol 31 (4) ◽  
pp. 419-432 ◽  
Author(s):  
Yuhei Inoue ◽  
Mikihiro Sato ◽  
Kevin Filo ◽  
James Du ◽  
Daniel C. Funk
Keyword(s):  
United States ◽  
Life Satisfaction ◽  
Emotional Support ◽  
Positive Association ◽  
Well Being ◽  
The United States ◽  
Professional Sport ◽  
Team Identification ◽  
Sport Events ◽  
Satisfaction Relationship

Elite and professional sport events have been recognized as potential mechanisms to enhance well-being. This multicountry study investigates how engagement in such events, behaviorally through live spectating and psychologically through team identification, is associated with life satisfaction. Data from Australia (N = 268) revealed a positive association between live spectating and life satisfaction through a two-wave design measuring live spectating and life satisfaction in separate surveys. Data from the United States (N = 564) confirmed the live spectating–life satisfaction relationship found in Study 1. Additionally, Study 2 revealed individuals with higher levels of team identification perceived greater emotional support from other fans, and this perception, in turn, predicted life satisfaction. Our findings provide sport managers with implications for positioning appeals in support of sport programs and designing events that facilitate engagement to promote life satisfaction in the community.

Geographic Distribution of Away Rotations Impacts the Urology Match Process in the United States

Urology ◽  
2021 ◽  
Author(s):  
Sagar Patel ◽  
Judy Hamad ◽  
Eric Wallen ◽  
Kristy Borawski ◽  
Davis Viprakasit ◽  
...  
Keyword(s):  
United States ◽  
Geographic Distribution ◽  
The United States ◽  
Match Process
Sign in / Sign up

Export Citation Format

Share Document