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1.
Sci Rep ; 11(1): 20155, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34635737

RESUMO

Understanding the species richness and ß-diversity patterns along elevation gradients can aid in formulating effective conservation strategies particularly in areas where local anthropogenic stresses and climate change are quite significant as in the Himalaya. Thus, we studied macrolichen richness and ß-diversity along elevational gradients at three sites, namely Kashmir (2200 to 3800 m a.m.s.l), Uttarakhand (2000-3700 m a.m.s.l) and Sikkim (1700 to 4000 m a.m.s.l) which cover much of the Indian Himalayan Arc. In all, 245 macrolichen species belonging to 77 genera and 26 families were collected from the three sites. Only 11 species, 20 genera and 11 families were common among the three transects. Despite the differences in species composition, the dominant functional groups in the three sites were the same: foliose, fruticose and corticolous forms. The hump-shaped elevation pattern in species richness was exhibited by most of the lichen groups, though an inverse hump-shaped pattern was also observed in certain cases. ß-diversity (ßsor) based on all pairs of comparisons along an elevation gradient varied from 0.48 to 0.58 in Kashmir, 0.03 to 0.63 in Uttarakhand and 0.46 to 0.77 in Sikkim. The contribution of turnover to ß-diversity was more than nestedness at all the three transects. Along elevation ß-diversity and its components of turnover and nestedness varied significantly with elevation. While species turnover increased significantly along the elevation in all the three transects, nestedness decreased significantly in Kashmir and Sikkim transects but increased significantly in the Uttarakhand transect. Except for the Kashmir Himalayan elevation transect, stepwise ß-diversity and its components of turnover and nestedness did not vary significantly with elevation. The present study, the first of its kind in the Himalayan region, clearly brings out that macrolichen species richness, ß-diversity, and its components of turnover and nestedness vary along the elevation gradients across the Himalayan Arc. It also highlights that contribution of turnover to ß-diversity is higher in comparison to nestedness at all the three transects. The variations in species richness and diversity along elevation gradients underpin the importance of considering elevational gradients in planning conservation strategies.


Assuntos
Altitude , Biodiversidade , Mudança Climática , Ecossistema , Líquens/fisiologia , Especificidade da Espécie
2.
Artigo em Inglês | MEDLINE | ID: mdl-33681863

RESUMO

Psychoactive substance use among children in Afghanistan is an issue of concern. Somewhere around 300,000 children in the country have been exposed to opioids that either parents directly provided to them or by passive exposure. Evidence-based and culturally appropriate drug prevention and treatment programs are needed for children and families. The goals of this study were to: (1) examine lifetime psychoactive substance use in girls and boys at treatment entry; and (2) examine differential changes in substance use during and following treatment between girls and boys. Children ages 10-17 years old entering residential treatment were administered the Alcohol, Smoking and Substance Involvement Screening Test for Youth (ASSIST-Y) at pre- and post-treatment, and at three-month follow-up. Residential treatment was 45 days for children and 180 days for adolescents and consisted of a comprehensive psychosocial intervention that included education, life skills, individual and group counseling and, for older adolescents, vocational skills such as embroidery and tailoring. Girls and boys were significantly different regarding lifetime use of five substances at treatment entry, with girls less likely than boys to have used tobacco, cannabis, stimulants, and alcohol, and girls more likely than boys to have used sedatives. Differences between boys and girls were found for past-three-month use of four substances at treatment entry, with girls entering treatment with higher past-three-month use of opioids and sedatives, and boys with higher past-three-month use of tobacco, cannabis, and alcohol. Change over the course of treatment showed a general decline for both girls and boys in the use of these substances. Girls and boys in Afghanistan come to treatment with different substance use histories and differences in past-three-month use. Treatment of children for substance use problems must be sensitive to possible differences between girls and boys in substance use history.

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