Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

GERMINAÇÃO DE SEMENTES E EMERGÊNCIA DE PLÂNTULAS DE Luehea divaricata Mart. et. Zucc. EM DIFERENTES SUBSTRATOS

This study aimed to evaluate different substrates on seed germination and seedling emergence of Luehea divaricata. The study was conducted at the Viveiro Florestal, DCFL, Universidade Federal de Santa Maria, RS. The fruits were collected from eight mother trees in the Morro Cerrito, Santa Maria, in July 2008. After processing, the seeds were stored in cold storage in paper bags for 4 months for the study of emergence, and 7 months for the evaluation of seed germination. Five substrates were evaluated for germination (T1: Roll paper, T2: On blotting paper, T3: Between blotting paper, T4: On sand: T5: On vermiculite) with four replications and four treatments for emergency (T1 : 100% peat, T2: 80% peat and 20% carbonized rice husk, T3: 60% peat and 40% carbonized rice husk, T4: 40% peat and 60% carbonized rice husk) with five replicates. We used a randomized experimental design. Analyzed variables were: germination (G), germination speed index (GSI) and mean time to germination (TMG) in the laboratory, and emergence was analyzed by the percentage of emergency (E), speed of emergence index (SEI) and mean emergence time (TME) in the nursery. The onset of germination occurred on the 6th day, the first count could be performed at 18 days, and assessments closed 35 days after the experiment. Moreover, the substrate over vermiculite (T5) had the highest percentage of G and IVG, corresponding to 42% and 0,678, respectively, while that T2 had the lowest TMG (14.80 days). The seedling emergence began at 21 days after sowing, being terminated at 70 days. The T1 and T2 showed the highest values of E, 84.37%, 91.87%, respectively, differing from T3 and T4. Furthermore, treatment T2 also showed the higher values of IVE (0.98) and TME (33.54 days). Therefore, the substrate vermiculite is indicated for seeds germination, and for seedling emergence, the substrate composed of a blend of 80% peat and 20% carbonized rice husk.O presente trabalho teve como objetivo avaliar diferentes substratos na germinação de sementes e emergência de plântulas de Luehea divaricata. O estudo foi realizado no Viveiro Florestal, DCFL, Universidade Federal de Santa Maria - RS. Os frutos foram coletados de oito árvores matrizes, no Morro do Cerrito, Santa Maria, em julho de 2008. Após o beneficiamento, as sementes permaneceram armazenadas em câmara fria, dentro de sacos de papel, por 4 meses, para o estudo de emergência de plântulas, e por 7 meses para a avaliação da germinação de sementes. Foram avaliados cinco substratos para germinação (T1: Rolo de papel; T2: Sobre papel mata-borrão; T3: Entre papel mata-borrão; T4: Sobre areia; T5: Sobre vermiculita) com quatro repetições, e quatro tratamentos para emergência (T1: 100% turfa; T2: 80% turfa e 20% casca de arroz carbonizada; T3: 60% turfa e 40% casca de arroz carbonizada; T4: 40% turfa e 60% casca de arroz carbonizada) com cinco repetições. Foi utilizado delineamento experimental inteiramente casualizado. Foram analisadas as variáveis germinação (G), índice de velocidade de germinação (IVG) e tempo médio de germinação (TMG) em laboratório e, para emergência, foi analisado o percentual de emergência (E), índice de velocidade de emergência (IVE) e tempo médio de emergência (TME) em viveiro. O início da germinação ocorreu no 6° dia, podendo a primeira contagem ser realizada aos 18 dias e as avaliações serem encerradas aos 35 dias após a instalação do experimento. Além disso, o substrato sobre vermiculita (T5) apresentou os percentuais mais altos de G e IVG, correspondendo a 42% e 0,678, respectivamente, enquanto que o T2 apresentou o menor TMG (14,80 dias). A emergência de plântulas teve início aos 21 dias após a semeadura, sendo finalizada aos 70 dias. Os tratamentos T1 e T2 apresentaram os maiores valores de E, 84,37%, 91,87%, respectivamente, diferindo estatisticamente de T3 e T4. Além disso, o tratamento T2 também apresentou os melhores valores de IVE (0,98) e TME (33,54 dias). Portanto, para germinação de sementes é indicado o substrato sobre vermiculita, e para emergência de plântulas, o substrato composto pela mistura de 80% turfa e 20% casca de arroz carbonizada

Características espectrais de folhas retiradas de cinco espécies vegetais na região do visível e do infravermelho próximo

The Remote Sensing has tools to assist the analysis of vegetation, because it interacts with electromagnetic energy thus enabling its spectral characterization. This study evaluates spectral differences of five different species through the mean values of leaf reflectance in the visible and near infrared, in order to know the change in reflectance between species: Camellia japonica L., Inga marginata Willd.; Handroanthus chrysotrichus (Mart. ex DC.) Bauhinia forficata Link.; Bougainvillea glabra and infer the best interval to differentiate them. There were two separate spectral regions: the visible region (450 to 690 nm) and near infrared (760 to 900 nm). The data were analyzed visually and statistically on software R with the following tests: Test of variance, test for Normality of the observations, analysis of variance and Tukey test applied to the visible and near infrared. It can be concluded that for the species: Bougainvillea glabra and Inga marginata Willd.; Camellia japonica L. and Inga marginata Willd.; Bougainvillea glabra and Handroanthus chrysotrichus (Mart. ex DC.) Camellia japonica L. and Handroanthus chrysotrichus (Mart. ex DC.) Bougainvillea glabra and Bauhinia forficata Link.; Camellia japonica L. and Bauhinia forficata Link.; Bauhinia forficata Link. and Inga marginata Willd.; Handroanthus chrysotrichus (Mart. ex DC.) Inga marginata Willd., respectively, the analysis in the near infrared region are more efficient, allowing a better contrast, already has a visible differentiation more effectively to the couples Bauhinia forficata Link. and Handroanthus chrysotrichus (Mart. ex DC.) Bougainvillea glabra and Camellia japonica L.Pages: 8552-855

Growth of yellow ipe in central region of Rio Grande do Sul State, Brazil

Objetivou-se analisar o crescimento em diâmetro e altura de indivíduos de Handroanthus chrysotrichus através de modelos em função da idade, em um povoamento no Município de São Pedro do Sul, RS. Os dados são de três árvores representativas da população e foram obtidos através de análise de tronco. O crescimento em diâmetro dos indivíduos de Handroanthus chrysotrichus em função da idade foi melhor explicado pelo modelo alométrico enquanto para a altura o modelo exponencial negativo apresentou melhores parâmetros estatísticos. Os modelos selecionados explicam mais de 92% da variação e se configuram como ferramentas adequadas para o manejo desta espécie.This study aimed to analyze the growth in diameter and height of individuals Handroanthus chrysotrichus through models based on age, in a stand in the municipality of São Pedro do Sul, State of Rio Grande do Sul, Brazil. Data are from three representative trees of the population and were obtained from stem analysis. The diameter growth of Handroanthus chrysotrichus trees in a function of age was best explained by the allometric model. For height the negative exponential model showed better statistical parameters. Selected models explain more than 92% of the variation and configure as adequate tools for the management of this species

ESTRUTURA HORIZONTAL E INFLUÊNCIA DE CARACTERÍSTICAS DO SOLO EM FRAGMENTO DE FLORESTA OMBRÓFILA MISTA

Os fragmentos florestais são importantes para a manutenção da biodiversidade, sendo fundamentais os estudos que visem obter informações para a conservação, recuperação e manejo desses ambientes. Dessa forma, o objetivo foi verificar a influência de atributos do solo na estrutura horizontal e na diversidade florística de um fragmento de Floresta Ombrófila Mista. O levantamento da vegetação foi realizado em 19 parcelas de 10 x 20 m. Nas parcelas, os indivíduos foram identificados e medidos conforme as seguintes classes de tamanho: Classe I - indivíduos com CAP (circunferência medida a 1,30 m da superfície do solo) ≥ 15 cm e Classe II CAP < 15 cm e diâmetro ≥ 1 cm. A vegetação foi analisada com base nos parâmetros fitossociológicos e a correlação entre a vegetação e variáveis do solo por meio da Análise de Correspondência Canônica. O fragmento apresenta baixa diversidade, com predomínio de poucas espécies na Classe de maior tamanho, entre essas destaca-se Araucaria angustifolia, porém sua reduzida densidade na regeneração natural poderá comprometer sua conservação no local. Espécies como Myrceugenia cucullata e Gymnanthes klotzschiana apresentam-se conservadas na floresta. Houve influência das características químicas do solo sobre a vegetação.Palavras-chave: fitossociologia, Araucaria angustifolia, CCA, campos de altitude. HORIZONTAL STRUCTURE AND INFLUENCE OF SOIL CHARACTERISTICS ON DISTRIBUTION IN FLORESTA OMBRÓFILA MISTA ABSTRACTForestry fragments are important to biodiversity maintenance, thus it is developing studies aiming to get information focused on the conservation, recovery and management of these environments. Therefore, aimed at featuring the horizontal structure, flora diversity and the influence of the soil variables from the arboreal-shrubby component within a Floresta Ombrófila Mista fragment. The survey on vegetation was performed in nineteen 10 x 20 m plots. Within these plots, the individuals were identified and measured according to the following size classes: Class I – individuals presenting DAP (circumference measured 1.30 m from soil surface) ≥ 15 cm and Class II CAP < 15 cm e diameter ≥ 1 cm. The vegetation was analyzed according to phytosociological parameters and to a correlation between the vegetation and the soil variables by means of a Canonical Correspondence Analysis. The fragment presents low diversity and the prevalence of few species in the bigger size class, among which stands out Araucaria angustifolia. However, its reduced density regarding natural regeneration may impair its own conservation within the local. Species such as Myrceugenia cucullata and Gymnanthes klotzschiana are preserved in the forest. There is influence from soil chemical features.Keywords: phytosociology, Araucaria angustifolia, CCA, altitude fields. DOI: http://dx.doi.org/10.5935/2318-7670.v05n02a1

Qualidade morfológica de mudas de Prunus sellowii submetidas a diferentes substratos

O objetivo desse trabalho foi avaliar diferentes proporções de casca de arroz carbonizada em substrato comercial, no crescimento de mudas de Prunus sellowii em viveiro. Os tratamentos foram compostos de: T1 - 100% substrato comercial (SC); T2 - 90% SC e 10% casca de arroz carbonizada (CAC); T3-80% SC e 20% CAC; T4 -70% SC e 30% CAC; T5 - 60% SC e 40% CAC; T6 - 50% SC e 50% CAC, em delineamento experimental inteiramente casualizado, com quatro repetições. Recomenda-se a adição de até 30% de CAC, sem prejuízos ao crescimento dessa espécie em viveiro

Substrate and irrigation scheme on the growth of Parapiptadenia rigida (angico-vermelho) seedlings

ABSTRACT: Parapiptadenia rigida (angico-vermelho) is a native arboreal species widely found in central and southern Brazil and is indicated for restoration of degraded areas due to its high plasticity to light gradients and ease adaptation to degraded environments. However, there is still a lack of information on this species regarding the production of quality seedlings, as well as the rational use of the resources involved. Thus, the objective of this study was to evaluate the effects of different substrates and irrigation schemes in the development of P. rigida seedlings. The experimental design used was randomized blocks, in a factorial scheme with split plots, with four substrate formulations (100% peat; 80% peat + 20% carbonized rice husk (CRH); 60% peat + 40% CRH; 40% peat + 60% CRH) and six irrigation schemes (4; 8; 12; 16; 20 and 24mm.day-1). At 180 days after emergence, the following parameters were evaluated: height, stem diameter, height and stem diameter ratio, shoot dry weight, root dry weight, total dry weight and Dickson Quality Index. Use of substrate composed of 80% peat + 20% carbonized rice husk and/or 100% peat, combined with irrigation scheme of 4mm day-1, resulted in the best growth of P. rigida seedlings