Composição, estrutura e similaridade florística da Floresta Atlântica, na Serra Negra, Rio Preto - MG

Serra Negra is a region surrounded by some stretches of mountain, covered by Atlantic Forests and cloud scrubs, located in the southern part of Zona da Mata of Minas Gerais, in Serra da Mantiqueira, between the rises of the massif of Itatiaia (RJ, SP e MG) and the Serra do Ibitipoca (MG). The aim of this study was to determine the composition, structure and floristic similarity of arboreal flora among three forest types of Atlantic Forest (Alluvial, Montane and Cloud Forest) and also the similarity with other studies. A total of 2,572 individuals was sampled, from 194 species, 59 families and 118 genera. The highest number of species was recorded in the families Myrtaceae (30 morphospecies), Lauraceae (20), Melastomataceae (17) and Fabaceae (13). The three vegetation types associated with different environmental conditions differ in their composition and structure. The alluvial proved with low diversity and stature and high ecological dominance. The cloud forest stood out for its typical elements of altitude over other common species in the area below the range, where diversity was higher. The tree flora of Sierra Negra presents various indicator species to characteristic distribution of highlands of southeastern Brazil.A Serra Negra, no município de Rio Preto (MG), estende-se por uma região com fisionomias florestais serranas da Mantiqueira e campos altimontanos, entre as elevações do maciço do Itatiaia (RJ, SP e MG) e da Serra do Ibitipoca (MG). Com o objetivo de investigar o comportamento das variáveis comunitárias da flora arbórea em condições diferentes de altitude e alagamento, determinou-se a composição florística, estrutura e similaridade entre três fragmentos de floresta (aluvial, montana e nebular) e a suas relações florísticas com estudos da região. Foram amostrados 2.572 indivíduos, identificados em 194 espécies, distribuídas em 59 famílias e 118 gêneros. As famílias com maior riqueza foram Myrtaceae (30 espécies), Lauraceae (20), Melastomataceae (17) e Fabaceae (13). Os três tipos de vegetação estudados, associados a diferentes condições ambientais, diferem entre si em sua composição e estrutura. A floresta aluvial revelou-se com reduzida diversidade, baixa estatura e alta dominância ecológica. A floresta nebular destacou-se por apresentar elementos típicos de altitude em detrimento de espécies freqüentes na região abaixo da escarpa da serra, onde a diversidade foi maior. A flora arbórea da Serra Negra, formada pelo conjunto das áreas estudadas, apresenta um conjunto considerável de elementos com distribuição característica de ambientes montanhosos do Sudeste do Brasil

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions. © Copyright

Diminishing benefits of urban living for children and adolescents’ growth and development

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified. © 2023, The Author(s)