Jarcilene Silva Almeida- Cortez

Accurate mapping of woody biomass and its temporal change is critical for understanding the global carbon balance, informing restoration and supporting evidence‐based policy on climate mitigation and livelihoods. The vegetation of the dry tropics, comprised largely of dry forests and savannas, holds substantial woody carbon stocks, but both stocks and change over time remain uncertain. Where Earth Observation (EO) data have been used to estimate change over time, different products give conflicting results on the direction, magnitude and location of change. We present pan‐dry‐tropical maps of aboveground carbon density (AGCD) and AGCD change at 100 m resolution for the years 2015–2024, developed using ALOS ScanSAR satellite radar observations calibrated with in situ measurements ( n = 237). These maps suggest an aboveground woody carbon pool (AGC) in the dry tropics of 25.3 2.0 PgC, ~13.0% of global AGC. Net AGC has increased by 0.43 0.07 PgC yr ⁻¹ , ~20.0% of the global net land sink. The overall net increase (0.43 PgC yr ⁻¹ ) is comprised of gross losses from deforestation and degradation (0.27 0.05 PgC yr ⁻¹ ) and gains due to densification and extensification of 0.59 0.1 PgC yr ⁻¹ , with the balance accounted for by small changes (change < 20% of AGCD; 0.11 PgC yr ⁻¹ ). Losses are equally split between degradation and deforestation, while gains are divided roughly 2:1 between the densification of woody ecosystems and expansion into previously grass‐dominated areas. These new maps, created with a dry‐tropics‐specific EO method, highlight the importance of tropical dry forests and savannas in the global carbon cycle. The prominent role of degradation‐related losses suggests that climate change mitigation will need to focus much more on reducing losses from overharvesting than at present. The widespread increases in carbon density and the increase in tree biomass into open systems present major challenges for biodiversity conservation, restoration and livelihoods.

Seasonally Dry Tropical Forests (SDTFs) play a crucial role in carbon storage and biodiversity conservation, yet they have been extensively altered by land-use change and increasing aridity associated with climate change. This study evaluated how secondary succession and aridity influence the functional structure of tree communities and carbon dynamics in Brazilian SDTFs. We sampled 78 plots (0.1 ha) representing three successional stages (early, intermediate, and late) across sites in the states of Minas Gerais, Bahia, and Paraíba. Carbon stocks were estimated using allometric equations, whereas temporal carbon dynamics were assessed in 54 remeasured plots. Carbon stocks increased along the successional gradient, accompanied by declines in stem density and community mean wood density. Late-successional forests exhibited the highest carbon stocks, highlighting the importance of conserving mature forests for maintaining aboveground carbon stocks and mitigating climate change. In contrast, aridity had no direct effect on mean structural and functional attributes but significantly reduced carbon gains and net carbon change, particularly in advanced successional stages. Carbon losses were negatively influenced by soil water-holding capacity and by temporal increases in community mean wood density. These findings indicate that secondary succession is the primary driver of carbon accumulation in SDTFs, whereas aridity mainly affects temporal carbon dynamics. Increasing aridity under future climate change scenarios may reduce net carbon accumulation and slow the structural and functional recovery of these forests.

The aim of this study was to evaluate how climatic seasonality affects the defense mechanisms of plants and how this is reflected in the richness and abundance of different guilds of herbivorous insects, using the species Ipomoea carnea subs. fistulosa as a model. Herbivore collections were carried out over 12 months, during this same period the phenology and herbivory was monitored in 30 marked plants, in addition to the analysis of the herbivory index in the dry and rainy season, in addition to collection and analysis of soil nutrients. Phenology showed strong seasonality, showing pivot of leaves and fruits emission during the dry season, and the reproductive phases of emission of buds and flowers peaked in the rainy season. A total of 10,199 herbivores were registered, distributed in 6 orders, and in four guilds. The total abundance of herbivores was greater during the dry season and the richness was greater during the rainy season. As for herbivore guilds, the abundance of leaf chewers-crushers was higher during the dry season, while flower and bud chewers-crushers were more abundant in the rainy season, whereas the suckers showed greater wealth and abundance in the rainy season. The results show a strong influence of climatic seasonality on the phenological patterns of the plant species. However this influence is very conspicuous in Seasonally Dry Tropical Forests, therefore, there are several biotic and abiotic factors responsible for these results. Factors such as interspecific competition and the distribution of food resources at a certain time of the season, can act in conjunction with climatic factors to shape insect abundance patterns.

As galhas desempenham um papel crucial como indicadores de alterações ambientais, sendo sua diversidade facilmente influenciada, tanto pelo efeito cascata 'top-down', quanto pelo efeito 'bottom-up', além da diversidade das plantas hospedeiras. Esses insetos estão associados a modificações na morfologia e anatomia das plantas, resultando em hipertrofia (aumento anormal do volume celular) ou hiperplasia (aumento anormal do número de células) nos órgãos e tecidos das plantas hospedeiras. Eles possuem alta especificidade em relação às plantas hospedeiras. Melastomataceae é uma das mais importantes famílias da flora neotropical e seus representantes são conhecidos por hospedarem uma alta diversidade de galhas. Nesse aspecto, o estudo objetivou realizar uma revisão sobre a riqueza de galhas na família Melastomataceae, apresentando uma análise completa sobre as principais espécies de plantas hospedeiras da família, assim como seus principais indutores. A revisão foi realizada buscando artigos científicos relevantes a partir das diferentes bases de dados: Portal de Periódicos da Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (Capes), ProQuest, SciELO, Scopus, SPELL e Springer Science databases no período de novembro-2022 a julho-2023. Os resultados apresentaram uma ampla caracterização das galhas presentes na família, assim como dados que mostraram o gênero Miconia Ruiz & Pavón com maior abundância (42,53%) e riqueza (n=15) de galhas. Considerando os insetos indutores de galhas, foi possível destacar a família Cecidomyiidae (Diptera) (39,71%). A análise da literatura revelou um aumento significativo na quantidade de artigos dedicados à riqueza de galhas nesta família. Constatou-se um crescimento contínuo na pesquisa, com estudos importantes conduzidos em várias regiões do mundo.

Através do avanço tecnológico e consequente aprimoramento de técnicas, vem se permitindo realizar estudos ambientais em grande escala e com a possibilidade de não precisar estar in loco na região de interesse. Como exemplos de ferramentas inovadoras temos os Índices de Vegetação, que são modelos matemáticos cuja função é avaliar a vegetação para compreender melhor através, por exemplo, da coloração e extensão. Logo, o presente estudo tem como objetivo analisar o desempenho do Chlorophyll Vegetation Index (CVI), um índice de vegetação para detectar plantas com altos teores de clorofila, um pigmento relacionado com a taxa fotossintética, em uma área de Mata Atlântica situada no município de Coruripe, em Alagoas. Com a aquisição das imagens do satélite Landsat 8, foi utilizado o software QGIS para o processamento dos dados e criação do mapa final. Após os cálculos serem feitos, foi possível observar a distribuição espacial dos locais e seus respectivos tamanhos em hectares, sendo eles: a classe vermelha, laranja e amarela que ocorrem principalmente nos limites da área e em alguns pontos dentro do fragmento com as três classes somando 40,32 ha; já as classes verdes somam 105,84, distribuídas principalmente dentro do fragmento. Esses dados indicam que na reserva há mais áreas com vegetação espaçada e densa do que locais sem vegetação ou com plantas arbustivas e com baixas taxas. Também foi permitida a identificação dos locais de áreas sem vegetação, áreas de clareira e de vegetação arbórea com pouca taxa de clorofila onde foi possível, através de análise in loco, relacionar com a deposição de fuligem na vegetação, o que pode estar influenciando na detecção do pigmento. Através da pesquisa foi possível ter um conhecimento de como se encontra a vegetação na Reserva do Planalto e pode-la caracterizá-la. Recomenda-se análises do índice em épocas de alta pluviometria para realizar comparação entre os períodos úmidos e secos.

Livro de Memórias do Sustentare & WIPIS (978-65-272-1291-1) - Caracterização Através Do Ndvi E Do Vari De Um Fragmento De Mata Atlântica Em Coruripe, Alagoas

The species composition and forest structure may change due to human disturbance. Changes in the arboreal component in regenerating forests has frequently been determined, but data on the herbaceous component are less available, especially those of tropical dry forests, despite their ecological and economic importance. Thus, in regenerating dry forests in the Brazilian semi-arid area, we tested the hypotheses that: (1) richness and diversity of herbaceous species are higher, but biomasses are lower in areas with longer regeneration periods; and (2) the aboveground herbaceous component is restricted to the rainy season, and species diversity, plant density and biomass vary with different patterns along this season. Four regeneration periods were analyzed: 2 (R2), 17 (R17), 39 (R39) and more than 60 years (mature caatinga) after grazed planted pasture was discontinued. The herbaceous component began growing after the onset of the rainy season (January) and disappeared in July after the rains ceased. Richness and plant density were highest in March, whereas biomass was highest in April and May. Mature caatinga and R39 had the highest herbaceous species richness (61 species), but the lowest biomasses (167 and 98 g m-2), with the opposite occurring in R2 (48 and 381 g m-2). Alpha diversity was highest in the mature caatinga, but beta diversity in R17. As a result, the herbaceous diversity increased while the plant density and biomass decreased as the regeneration period increased.

Evaluating the diversity of multiple taxa is fundamental to understand community assembly and to assess the integrity and functionality of tropical secondary forests. In this study, we analyzed the natural regeneration of tropical dry forests (TDFs) in three regions of Brazil using Hill–Simpson diversity, abundance and β‐diversity of trees and five groups of insects (herbivores, fruit‐feeding butterflies, ants, culicid mosquitoes and dung beetles). Sampling was conducted in 39 0.1 ha plots using a chronosequence approach (13 plots in early, intermediate and old‐growth forests). We evaluated the contribution of three different levels to γ‐diversity: α (within plots), β ¹ (among plots) and β ² (among successional stages), and further determined the relative importance of turnover (species replacement) and nestedness (differences in species number among sites) to β ² . Our results showed that, unexpectedly, the Hill–Simpson diversity was consistently higher in early than old‐growth stages for all regions, but varied more widely in the intermediate stages. For each group separately, the same trend was observed for butterflies, ants, dung beetles and herbivores and did not differ among stages for mosquitoes. Successional differences in abundance were only detected for trees (increasing along the gradient) and for mosquitoes (decreasing). According to our expectations, the additive partitioning analysis showed that β ² ‐diversity contributed more to γ‐diversity than β ¹ ‐diversity, when all taxa were considered together and for most of them separately (except for butterflies and dung beetles). Most of the β ² ‐diversity was due to species turnover, but this contribution varied among groups and regions, with the highest turnover for herbivores and the lowest for dung beetles. Our results suggest that the Hill–Simpson diversity and changes in species composition (as given by β ² ‐diversity) are better indicators of forest natural regeneration than raw species richness, corroborating previous studies with plants and animals.