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1.
Mar Pollut Bull ; 205: 116615, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38917497

RESUMO

Coastal and estuarine systems play an important role in the maintenance of marine biodiversity, providing nursery, feeding, developmental and reproductive areas for terrestrial and aquatic species. The Fundão dam collapse is considered one of the biggest environmental disasters in Brazil, causing great social, economic and ecological damage in the affected areas. In our study, we used beta diversity and its components as a tool to monitor the spatio-temporal variation of fish larvae in four marine areas adjacent to the Doce River. The results show that the four areas undergo different spatio-temporal dynamics, with the composition of fish larvae in the Doce being simplified in the last years after the dam burst, compared to the other adjacent marine areas. In addition, turbidity is an important factor that has caused the homogenization of the larval composition of the Doce, demonstrating that mud resuspension events can cause a decrease in diversity and also suggesting the toxicity of the mud composition. The change from negative to positive additive and colonizing components in recent years suggests a slight recovery of diversity in the Doce compared to other marine areas. Finally, we have shown that some species may be tolerant to the impact, but with probable behavioral, energetic and physiological costs, which justifies the constant monitoring of these areas.


Assuntos
Biodiversidade , Monitoramento Ambiental , Peixes , Larva , Animais , Brasil , Larva/crescimento & desenvolvimento , Rios
2.
Environ Monit Assess ; 193(4): 183, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712944

RESUMO

In a world where pristine water is becoming scarcer, the need to reuse water becomes imperative. In this context explaining the water quality, purpose fitness and the parameters or conditions of the water body to adjust so as to improve its quality, are of great relevance. The goal of the present study was the use of water, riverine, and biodiversity quality indices to assess the condition of the studied urban wetland, since no single index can provide a complete health assessment of a water body. Decision trees were also used to elucidate the best water parameters to mend in order to recover the overall health of the urban wetland. The decision trees identified relevant physicochemical parameters as well as their approximate concentration at which a healthy water environment can be sustained for zooplankton and proved to be a powerful and simple alternative to customary approaches. Suspended particles and phosphates proved to be important parameters with concentrations approximately lower than 88 mg L-1 and 11 mg L-1, respectively, for a good biodiversity index of zooplankton. Ammonia, total coliforms, BOD, nitrates, and sodium were the main parameters that affected the water quality index. The vegetation coverage and its structure were the driving factors in the riverine quality index of the wetland.


Assuntos
Monitoramento Ambiental , Áreas Alagadas , Animais , Biodiversidade , Árvores de Decisões , Qualidade da Água
3.
J Ethnobiol Ethnomed ; 16(1): 42, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32690045

RESUMO

BACKGROUND: Home gardens (HGs) are hotspots of in situ agrobiodiversity conservation. We conducted a case study in Tabasco, México, on HG owners' knowledge of HG ecological, economical and socio-cultural multifunctionality and how it relates to agrobiodiversity as measured by species richness and diversity. The term multifunctionality knowledge refers to owners' knowledge on how HGs contribute to ecological processes, family economy, as well as human relations and local culture. We hypothesized a positive correlation between owners' multifunctionality knowledge and their HGs' agrobiodiversity. METHODS: We inventoried all perennial species in 20 HGs, determined observed species richness, calculated Shannon diversity indexes and analysed species composition using non-metric multidimensional scaling (NMDS). Based on literature, semi-structured interviews and a dialogue of knowledge with HG owners, we catalogued the locally recognized functions in the ecological, economic and socio-cultural dimensions. We determined the score of knowledge on each function in the three dimensions on explicit scales based on the interviews and observed management. We determined Spearman rs correlations of HGs' observed species richness, Shannon diversity index (H) and of HGs' scores on NMDS-axis and multifunctionality knowledge scores. We dialogued on the results and implications for agrobiodiversity conservation at workshops of HG owners, researchers and local organizations. RESULTS: HG agrobiodiversity and owners' multifunctionality knowledge in the study area showed large variation. Average richness was 59.6 perennial species, varying from 21 to 107 species, and total observed richness was 280 species. A total of 38 functions was distinguished, with 14, 12 and 12 functions in the ecological, economic and socio-cultural dimensions. Total multifunctionality knowledge scores varied from 64.1 to 106.6, with an average of 87.2. Socio-cultural functionality knowledge scores were the highest, followed by scores in the ecological and economic dimensions. Species richness and Shannon H were significantly correlated with ecological functionality knowledge (rs = 0.68 and P < 0.001 in both cases), and species richness was also correlated with economic functionality knowledge (rs = 0.47, P = 0.03). Species composition scores on the first and second axes of NMDS was significantly correlated with knowledge of ecological multifunctionality, with rs = 0.49 resp-0.49 and P = 0.03 in both cases. Other functionality knowledge scores showed no correlation with NMDS scores. Dialogue in workshops confirmed the interwovenness of multifunctionality knowledge and agrobiodiversity. CONCLUSION: The rich agrobiodiversity of home gardens cherished by rural families in Tabasco relates with the knowledge about HG functionality in the ecological and economic dimensions. Also, species composition relates with ecological functionality knowledge. The socio-cultural functionality knowledge, which includes many elements beyond the individual HG, is not correlated with agrobiodiversity, but had the highest scores. Our results show that multifunctionality knowledge provides many opportunities for the participative conception and planning of policies and actions necessary to conserve agrobiodiversity.


Assuntos
Biodiversidade , Jardins , Conhecimento , Conservação dos Recursos Naturais , Etnobotânica , Jardinagem , Humanos , México
4.
Med Biol Eng Comput ; 56(11): 2125-2136, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29790102

RESUMO

Lung cancer presents the highest cause of death among patients around the world, in addition of being one of the smallest survival rates after diagnosis. Therefore, this study proposes a methodology for diagnosis of lung nodules in benign and malignant tumors based on image processing and pattern recognition techniques. Mean phylogenetic distance (MPD) and taxonomic diversity index (Δ) were used as texture descriptors. Finally, the genetic algorithm in conjunction with the support vector machine were applied to select the best training model. The proposed methodology was tested on computed tomography (CT) images from the Lung Image Database Consortium and Image Database Resource Initiative (LIDC-IDRI), with the best sensitivity of 93.42%, specificity of 91.21%, accuracy of 91.81%, and area under the ROC curve of 0.94. The results demonstrate the promising performance of texture extraction techniques using mean phylogenetic distance and taxonomic diversity index combined with phylogenetic trees. Graphical Abstract Stages of the proposed methodology.


Assuntos
Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Pulmão/patologia , Algoritmos , Bases de Dados Factuais , Humanos , Reconhecimento Automatizado de Padrão/métodos , Filogenia , Curva ROC , Sensibilidade e Especificidade , Máquina de Vetores de Suporte , Taxa de Sobrevida , Tomografia Computadorizada por Raios X/métodos
5.
J Digit Imaging ; 30(6): 812-822, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28526968

RESUMO

Lung cancer is pointed as the major cause of death among patients with cancer throughout the world. This work is intended to develop a methodology for diagnosis of lung nodules using images from the Image Database Consortium and Image Database Resource Initiative (LIDC-IDRI). The proposed methodology uses image processing and pattern recognition techniques. In order to differentiate between the patterns of malignant and benign nodules, we used phylogenetic diversity by means of particular indexes, that are: intensive quadratic entropy, extensive quadratic entropy, average taxonomic distinctness, total taxonomic distinctness, and pure diversity indexes. After that, we applied the genetic algorithm for selection of the best model. In the tests' stage, we applied the proposed methodology to 1405 (394 malignant and 1011 benign) nodules. The proposed work presents promising results at the classification into malignant and benign, achieving accuracy of 92.52%, sensitivity of 93.1% and specificity of 92.26%. The results demonstrated a good rate of correct detections using texture features. Since a precocious detection allows a faster therapeutic intervention, thus a more favorable prognostic to the patient, we propose herein a methodology that contributes to the area in this aspect.


Assuntos
Diagnóstico por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/genética , Nódulo Pulmonar Solitário/diagnóstico por imagem , Máquina de Vetores de Suporte , Tomografia Computadorizada por Raios X/métodos , Variação Genética/genética , Humanos , Processamento de Imagem Assistida por Computador/métodos , Pulmão/diagnóstico por imagem , Reconhecimento Automatizado de Padrão/métodos , Filogenia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Environ Entomol ; 45(6): 1404-1414, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-28028087

RESUMO

We describe the spatial variation in the structure and composition of the communities of insects visiting the inflorescences of Flaveria ramosissima Klatt, Florestina pedata (Cav.) Cass., and Parthenium bipinnatifidum (Ort.) Rollins (Asteraceae) in a xeric environment in Central Mexico. Inflorescences of the three Asteraceae were visited by a total of 96 species of Hymenoptera, Diptera, Lepidoptera, Coleoptera, and Hemiptera. Total species richness of floral visitors to the three Asteraceae and total abundance of insects of Fl. pedata and P. bipinnatifidum did not differ between low and high vegetation cover sites. Total abundance of insects visiting the inflorescences of F. ramosissima and abundance of Hymenoptera in all three Asteraceae were higher at the low vegetation coverage (LVC) site than at the high vegetation coverage (HVC) one. Diversity of insects of Fl. pedata and P. bipinnatifidum was higher at the HVC site. However, in F. ramosissima diversity was higher at the LVC site. The communities of insects of each Asteraceae were dissimilar between sites. These differences can be attributed to variation in the abundance of Lepidophora (Diptera: Bombyliidae), Miridae (Hemiptera), Melyridae (Coleoptera), Tiphiidae (Hymenoptera), Myrmecocystus mexicanus Wesmael, and Dorymyrmex grandulus (Forel) (Hymenoptera: Formicidae). The first three insect groups were sensitive to LVC, high temperature, and low humidity, whereas the last three tolerated those same environmental conditions. Changes in temperature, humidity, and resources associated with vegetation coverage seem to differentially affect each species of floral visitors of the three Asteraceae species studied.


Assuntos
Asteraceae , Biodiversidade , Insetos/fisiologia , Polinização , Animais , Asteraceae/fisiologia , Flaveria/fisiologia , Cadeia Alimentar , México
7.
Pharm Biol ; 54(9): 1628-40, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26857000

RESUMO

Context Worldwide ethnobotanical research has shown the importance of home gardens as sources of medicinal plants. These resources are worthy of further study in the Argentinean Atlantic Forest due to the richness of medicinal flora and their importance for local people. Objective We studied richness, composition, cultural importance and medicinal uses of plants in home gardens of rural, semirural and urban areas in the Iguazú Department (Misiones, Argentina). Our hypothesis claims that people living in different environments have a similar array of medicinal plants in their gardens and they use them in a similar way. Materials and methods The analysis was based on 76 interviews and plant inventories of home gardens. During guided walks in gardens, voucher specimens were collected. To analyse composition, Simpson similarity index was applied and a new index was proposed to measure culturally salient species. Results All the environments had similar species composition with species differing in less than 30% of them. The most culturally salient taxa were Mentha spicata L. (Lamiaceae), in rural, Artemisia absinthium L. (Asteraceae), in semirural, and Aloe maculata All. (Xanthorrhoeaceae), in urban areas. The body systems treated with medicinal plants were similar across study sites. Discussion The results suggest a "core repertoire" of medicinal plants and a widespread exchange of plants among local population. The cultural importance index informs us about plant adaptability, based on the efficacy and the versatility of medicinal resources. Conclusion In this changing context where mobility and migrations constitute everyday life, medicinal plants in home gardens are part of local healthcare sovereignty.


Assuntos
Etnobotânica , Jardinagem , Medicina Tradicional , Plantas Medicinais/crescimento & desenvolvimento , População Rural , População Urbana , Argentina , Características Culturais , Folclore , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Fitoterapia , Plantas Medicinais/classificação
8.
J. health inform ; 8(supl.I): 1061-1070, 2016. ilus, tab
Artigo em Português | LILACS | ID: biblio-906812

RESUMO

Apresenta uma metodologia de auxílio no diagnóstico por computador (Computer-Aided Diagnosis - CADx) para classificação de malignidade ou benignidade dos nódulos pulmonares em imagens de tomografia computadorizada. O uso dos índices de diversidade filo genética para extração das características dos nódulos, a classificação é realizada com a ferramenta WEKA usando múltiplos classificadores, validação dos resultados com as métricas kappa, Area Under the Curve, sensibilidade, especificidade e acurácia. Os testes mostraram resultados bem objetivos e robustos para uma metodologia CADx com uma acurácia de 98,1%, sensibilidade 98,7%, especificidade 97,9%, um kappa de 0,95 e uma Area Under the Curve de 0,99. Os resultados obtidos comprovaram o bom desempenho das técnicas de extração de características de textura através dos índices apresentados, com uma precisão de 98,1%.


Present a methodology to assist in the computer diagnosis (Computer-Aided Diagnosis -CADx) to classify pulmonary nodules in malignant and benign in CT images. Using phylogenetic diversity index to extract the characteristics of the nodes, the classification made with WEKA tool, validating the results with the following metrics kappa, ROC curve, sensitivity, specificity and accuracy. The tests showed very accurate and robust results for integration in a CADx tool with an accuracy of 98.1%, 98.7% sensitivity, 97.9% specificity, a kappa of 0.95 and an AUC of 0.99. The results indicated a good performance of texture extraction techniques through the indexes presented with an accuracy of 98.1%.


Assuntos
Humanos , Filogenia , Interpretação de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X , Classificação , Neoplasias Pulmonares/diagnóstico , Congressos como Assunto
9.
Rev. biol. trop ; Rev. biol. trop;62(4): 1609-1623, oct.-dic. 2014. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-753714

RESUMO

Alsophila firma is a tree fern that is distributed mainly in tropical montane cloud forest (TMCF) and is considered as a threatened species. Arbuscular mycorrrhizal fungi (AMF) have been proposed as an alternative in rescue programs of endangered species. However, our knowledge about diversity of AMF and mycorrhizal status of the species of TMCF is limited. In Mexico TMCF shows different degrees of conservation because of fragmentation and land use change. In this study, we evaluated the level of colonization, richness and abundances of spores of AMF in three fragments with different conservation status: conserved (100 years), secondary vegetation (17 years) and disturbed. For this, soil samples and roots were collected from five individuals of A. firma per site, with at least 100m away from each other; a total of 100cm of roots were analysed per site. Root samples showed AMF and occasionally dark septate fungi (DSF) colonizations. For the overall study, 19 species of AMF were recorded: Gigaspora (7), Acaulospora (4), Glomus (4), Funneliformis (2), Sclerocystis (1) and Scutellospora (1). The dominant species in the three sites were Funneliformis geosporum and Acaulospora scrobiculata. The highest diversity (H’) and evenness (J’) (p<0.05) were found in the conserved site (H’=1.7, J’=0.66), when compared to the secondary vegetation (H’=1.5, J’=0.61), and the disturbed site (H’=0.74, J’=0.41). Statistical analysis showed that the AMF degree of colonization was significantly higher (p<0.05) in the conserved site; although, the disturbed site showed low richness and abundances of AMF, the degree of root colonization did not differ statistically (p<0.05) with the secondary vegetation site. Chao2 (Richness estimation model) showed that the number of analysed samples were sufficient to represent the structure of the AMF communities with values >90%. The present study confirmed that A. firma is a mycorrhizal species that exhibits high levels of colonization even in disturbed sites. We suggest that F. geosporum and A. scrobiculata may have the potential to inoculate the gametophyte and young sporophyte of A. firma, to support restoration programs, because of their abundances and high tolerance to disturbed sites.


Alsophila firma es un helecho arborescente que crece principalmente en bosque mesófilo de montaña (BMM) y se encuentra en la categoría de riesgo. Los hongos mico- rrízicos arbusculares (HMA) se han propuesto como una alternativa para programas de recuperación de especies nativas en peligro. Sin embargo, sabemos poco sobre la diversidad de HMA y del estatus micorrízico de las espe- cies vegetales del BMM. En México el BMM presenta diferentes grados de conservación debido a la fragmentación y el cambio de uso de suelo. Se evaluó el grado de colonización, riqueza y abundancia de esporas de los HMA presentes en fragmentos de BMM con diferente historia de manejo: conservado (100 años), en recuperación (17 años) y alterado. Se estudiaron muestras de suelo y raíces toma- das de 5 individuos de A. firma por cada sitio, con al menos 100m de distancia entre individuos. Se analizaron en total 100cm de raíz por cada sitio. Las muestras de raíz presentaron colonización principalmente de HMA y ocasionalmente por hongos septados oscuros (HSO). Se encontraron 19 especies: Gigaspora (7), Acaulospora (4), Glomus (4), Funneliformis (2), Sclerocystis (1) y Scutellospora (1). Las especies dominantes en los tres sitios fueron Funneliformis geosporum y Acaulospora scrobiculata. La mayor diversidad (H’) y equitatividad (J’) (p<0.05) se presentaron en el sitio conservado (H’=1.7; J’ 0.66) con respecto al sitio en recuperación (H’=1.5, J’ 0.61) y alterado (H’=0.74, J’=0.41). Los niveles de colonización micorrízica total de raíz fueron estadísticamente mayores (p<0.05) en el sitio conservado. Aunque el sitio alterado presenta una baja riqueza y abundancia de HMA la colonización micorrízica total de raíz no fue estadísticamente diferente (p<0.05) respecto al sitio en recuperación. El estimador Chao2 indica que las muestras analizadas reflejan la estructura general de la comunidad de HMA con valores superiores al 93%. El presente estudio confirma que A. firma es una especie micorrízica con altos niveles de colonización incluso en sitios alterados. Se sugiere que las especies F. geosporum y A. scrobiculata por su alta tolerancia a sitios alterados pueden tener potencial para inocular gametofitos y esporofitos de A. firma para incrementar la supervivencia en programas de restauración.


Assuntos
Gleiquênias/microbiologia , Micorrizas/fisiologia , Ecossistema , Florestas , México , Micorrizas/classificação , Clima Tropical
10.
Rev. bras. eng. biomed ; 30(1): 27-34, Mar. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-707135

RESUMO

INTRODUCTION: Breast cancer is the second most common type of cancer in the world, being more common among women and representing 22% of all new cancer cases every year. The sooner it is diagnosed, the better the chances of a successful treatment are. Mammography is one way to detect non-palpable tumors that cause breast cancer. However, it is known that the sensitivity of this exam can vary considerably due to factors such as the specialist's experience, the patient's age and the quality of the images obtained in the exam. The use of computational techniques involving artificial intelligence and image processing has contributed more and more to support the specialists in obtaining a more precise diagnosis. METHODS: This paper proposes a methodology that exclusively uses texture analysis to describe features of masses in digitized mammograms. To increase the efficiency of texture feature extraction, the diversity index's capability to detect patterns of species co-occurrence is used. For this purpose, the Gleason and Menhinick indexes are used. Finally, the extracted texture is classified using the Support Vector Machine, looking to differentiate the malignant masses from the benign. RESULTS: The best result was obtained using the Gleason index, with 86.66% accuracy, 90% sensitivity, 83.33% specificity and an area under the ROC Curve (Az) of 0.86. CONCLUSION: Both indexes showed statistically similar performance; however, the Gleason index was slightly superior.

11.
Psicol. teor. prát ; 15(2): 119-129, ago. 2013. tab
Artigo em Português | LILACS | ID: lil-717657

RESUMO

Este artigo visa apresentar, com exemplos empíricos, três índices calculáveis a partir de dados de evocações livres. Dois desses índices foram elaborados por Flament e Rouquette (2003) e indicam o grau de diversidade e de raridade das evocações. O terceiro índice permite o estudo da proporção de elementos comuns a dois corpora de evocações, por isso foi nomeado de índice de comunidade. A partir desses três indicadores, é possível ter informações sobre o grau de compartilhamento social de cada objeto, seu nível de idiossincrasia e a proporção de comunidade entre dois corpora. Essas informações, quando associadas a outras técnicas, podem ser úteis para uma melhor compreensão da relação população-objeto.


This paper aims at presenting three indexes that can be calculated from free evocation data. Two of those indexes were elaborated by Flament and Rouquette (2003), and they indicate the diversity and rarity degrees of evocations. The third index allows for the study of the proportion of elements common to two evocation corpora. From these three indicators it is possible to have information about the degree of social sharing of each object, their idiosyncrasy level and the community proportion between two corpora. When associated with other techniques, such information might be useful for a better understanding of the population-object relationship.


Este artículo tiene como objetivo presentar, con ejemplos empíricos, tres índices estimados a partir de datos de evocaciones libres. Dos de estos índices fueron desarrollados por Flament y Rouquette (2003) e indican el grado de diversidad y rareza de las evocaciones. El tercer índice permite estudiar la proporción de elementos comunes a los dos corpora de evocaciones, por lo que fue llamado el índice de la comunidad. A partir de estos tres indicadores es posible tener información sobre el grado de participación social de cada objeto, su nivel de la idiosincrasia y la proporción de comunidad entre los dos corpora. Esta información, cuando se combina con otras técnicas, puede ser útil para una mejor comprensión de la relación población-objeto.

12.
Rev. biol. trop ; Rev. biol. trop;61(1): 111-124, Mar. 2013. graf
Artigo em Espanhol | LILACS | ID: lil-674065

RESUMO

In Argentina, the grasslands of Pampas region comprise approximately 15% of the country. As in other grasslands of the world, grasshoppers are among the most important native herbivores. Their economic importance has been recognized in Argentina since the mid to late nineteenth century, since outbreaks of different species have become recurrent phenomena. Therefore, the main objective of this work was to study their diversity and distribution in grasslands of the Southern Pampas region (Laprida county, Buenos Aires province), as one of the most affected areas. The study was conducted during five seasons (2005-10). Sampling sites were represented by the most common plant communities in this area, classified in four categories: native grasslands, disturbed grasslands, implanted pastures and halophilous grasslands. The samplings were conducted from mid-spring to early autumn, with five or six samples per season. We estimated the following population descriptors: species richness (S), eveness (E), dominance (J), and diversity index (H´). In order to evaluate the similitude of the grasshopper communities present in the different plant communities, we used qualitative and quantitative coefficients of similitude. A total of 22 species of grasshoppers were collected, of which 21 belong to the family Acrididae. The subfamily Melanoplinae was the most diverse with eight species. The largest species richness was recorded in native grasslands (18). The different communities of grasshoppers had similar indices of evenness and dominance (p>0.05). Considering all plant communities, the average value of Shannon-Wiener index was 1.58±0.075. There was a positive correlation between evenness index and species richness (p<0.05). The diversity index H’ was different between plants communities (p<0.05), and it was higher in the disturbed grassland (1.75±0.096, p<0.05) than in the halophilous grasslands (1.34±0.12). Native and disturbed grasslands had a higher plant richness than halophilous grasslands and implanted pastures (p<0.05). There was a positive relationship between plant richness and grasshoppers species richness, and diversity of grasshoppers. According to the qualitative indices applied, the similitude between different grasshopper communities was higher than 60%. In general, the species that had a higher frequency of occurrence showed greater abundance and distribution. Covasacris pallidinota, Dichroplus elongatus, D. maculipennis, Borellia bruneri and B. pallid were the most widely distributed species, most of them (12) showed a restricted distribution and few (five) an intermediate distribution.


Los acridios son componentes nativos de los pastizales, dichos sistemas han sido modificados debido a la intensificación de las actividades agrícola-ganaderas y por lo tanto se considera importante estudiar las comunidades de acridios asociadas. Se estudió la diversidad y distribución de acridios en el Sur de la región pampeana a través de muestreos realizados en las comunidades vegetales más representativas del partido de Laprida, provincia de Buenos Aires, durante cinco temporadas (2005-2010). Se recolectaron 22 especies. La subfamilia Melanoplinae fue la más diversa (ocho especies). La mayor cantidad de especies se observó en los pastizales nativos (18). La diversidad en los pastizales alterados (1.75±0.096) fue superior (p<0.05) a la de los pastizales halófilos (1.34±0.12). La riqueza de plantas en los pastizales nativos y los pastizales alterados fue superior (p<0.05) a la de las demás comunidades. Se registro una relación positiva entre la riqueza de plantas y las variables riqueza y diversidad de acridios. La similitud entre las comunidades de acridios estimada por los índices cualitativos fue superior al 60%. En general, las especies que tuvieron una mayor frecuencia de aparición, mostraron una mayor abundancia y distribución. Covasacris pallidinota, Dichroplus elongatus, D. maculipennis, Borellia bruneri y B. pallida fueron las de mayor distribución, cinco especies tuvieron una distribución intermedia y la mayoría (12) una distribución restringida.


Assuntos
Animais , Biodiversidade , Gafanhotos/classificação , Poaceae , Argentina , Densidade Demográfica , Dinâmica Populacional
13.
Rev. bras. entomol ; Rev. bras. entomol;57(1): 59-66, jan.-mar. 2013. graf, mapas, tab
Artigo em Inglês | LILACS | ID: lil-669495

RESUMO

Orthoptera assemblages associated with macrophytes of floodplain lakes of the Paraná River. The Orthoptera assemblage composition varies considerably, depending on habitat type. This study examines the spatiotemporal relationship between plant diversity, hydrometric level, environmental variables and the Orthoptera richness and abundance in floodplain lakes connected permanently or temporarily with the main channel of the Paraná River. The grasshoppers were collected fortnightly (April 2006May 2007). A total of 17 species were recorded and classified according to their frequency of occurrence in constant (7), accessory (4), or accidental (6) species. In the two lakes, the greater species richness and abundance was recorded in summer, thereby coinciding with the highest water level of the Paraná River. The most significant correlation between the orthopteran richness and abundance was with the water level. The aquatic plant richness was significantly different between the lakes, but the vegetation was dominated by Eichhornia crassipes (Mart.) Solms. (Liliales, Pontederiaceae). The lake, which was connected permanently, presented the highest values of diversity and abundance, proving to be a more diverse assemblage. The beta diversity was higher in the temporary connected lake than in the permanently connected one. The orthopterans assemblages were different between the lakes, Cornops aquaticum and Tucayaca gracilis were the species that contributed more to the level of dissimilarity. C. aquaticum was more representative in the lake temporarily connected, while T. gracilis in the permanent connected one. The water level of the Paraná River and the connectivity of the floodplain lakes play an important role to explain the abundance and richness of their orthopteran assemblages.

14.
Braz. j. biol ; Braz. j. biol;72(2): 305-310, May 2012. tab
Artigo em Inglês | LILACS | ID: lil-639439

RESUMO

This study sampled the diversity of Braconidae (Hymenoptera) in three different ecosystems: a degraded pasture, a secondary forest and an area in recovery process using native tree seedlings. The objective was to verify the use of those insects as a tool to check the local conservation by examining Shannon's diversity index. Ten subfamilies were identified, and Microgastrinae was predominant in a number of individuals. The diversity index calculated varies among the sampled areas, thus showing a correlation with vegetation cover with the number of individuals collected and number of subfamilies found. The results showed changes in the community of Braconidae, in the recovery area between the first and second year of study, thereby leading to the conclusion that they are indicators of environmental quality.


Este estudo amostrou a diversidade de Braconidae (Hymenoptera) em três ecossistemas distintos: pastagem degradada, mata secundária e área em processo de recuperação com utilização de mudas de árvores nativas. O objetivo foi verificar a possibilidade de utilização desse grupo de insetos como ferramenta para identificar o estado de conservação local por meio da análise do índice de diversidade de Shannon. Foram identificadas dez subfamílias, com predominância em número de indivíduos de Microgastrinae. Os índices de diversidade calculados permitiram diferenciar as áreas amostradas, apresentando uma correlação da cobertura vegetal com o número de indivíduos coletados e o numero de subfamílias encontradas. O método evidenciou alteração na comunidade de Braconidae na área em recuperação, entre o primeiro e o segundo ano de estudo, demonstrando que são insetos indicadores de qualidade ambiental.


Assuntos
Animais , Biodiversidade , Monitoramento Ambiental/métodos , Himenópteros/classificação , Brasil , Conservação dos Recursos Naturais , Densidade Demográfica
15.
Biosci. j. (Online) ; 28(2): 277-296, mar./apr. 2012. ilus, tab
Artigo em Português | LILACS | ID: biblio-912566

RESUMO

A caatinga está presente em quase toda área de clima semiárido do nordeste brasileiro e apresenta formações vegetais, fisionômica e florísticamente distintas. O estudo foi realizado em duas áreas de remanescentes de caatinga, um de embasamento cristalino (Fazenda Trussu - 6°19'46"S e 39°22'37''O) e outro sedimentar (Fazenda Elmo Moreno - 6º21'78"S e 39º14'24''O), localizadas no município de Iguatu, região centro-sul, Ceará. As coletas botânicas foram feitas quinzenalmente nos quatro meses de chuvas e mensalmente nos meses secos, durante o período de abril de 2007 a dezembro de 2010. Coletou-se ervas, subarbustos, arbustos, árvores, epífitas, hemiparasitas e lianas. A coleção botânica encontra-se depositada no acervo do Herbário MOSS. Na Fazenda Trussu coletou-se 186 espécies, distribuídos em 135 gêneros e 53 famílias e na Fazenda Elmo Moreno coletou-se 148 espécies, distribuídas em 107 gêneros e 46 famílias. Confirma-se a hipótese de que a vegetação da caatinga se diferencia de acordo com o tipo de substrato presente (cristalino ou sedimentar), exercendo a profundidade do solo influência sobre a distribuição e competição de espécies lenhosas. O registro de um significativo número de espécies vegetais lenhosas exclusivas e raras nas áreas estudadas indica que os trabalhos realizados até o momento ainda não amostraram ou cobriram considerável número de espécies presentes nas diferentes regiões do bioma caatinga.


The scrub is present in nearly every area of semi-arid northeast of Brazil and has vegetation, physiognomic and floristically distinct. The study was conducted in two areas of remnant scrub, one of the crystalline basement (Farm Trussu - 6 ° 19' 46 "S and 39 ° 22' 39''O) and other sedimentary (Farm Elmo Moreno - 6 of 21 '78 "S and 39 º 14' 24''O) located in the municipality of Iguatu, south-central, Ceará. The botanical collections were made fortnightly in four months and monthly rainfall in the dry months during the period April 2007 to December 2010. Was collected herbs, shrubs, trees, epiphytes, and lianas hemiparasites. The botanical collection is deposited in the Herbarium MOSS. On Farm Trussu was collected 186 species distributed in 135 genera and 53 families in the Farm and Elmo Moreno was collected 148 species belonging to 107 genera and 46 families. Confirms the hypothesis that the caatinga vegetation differs according to the type of substrate present (crystalline or sedimentary), exerting influence on soil depth distribution and competition of woody species. The registration of a significant number of woody plant species unique and rare in the study area indicates that the work performed so far have not covered or sampled a considerable number of species present in different regions of the Scrubland biome.


Assuntos
Ecossistema , Zona Semiárida , Flores , Biodiversidade
16.
Braz. J. Biol. ; 72(2)2012.
Artigo em Inglês | VETINDEX | ID: vti-446848

RESUMO

This study sampled the diversity of Braconidae (Hymenoptera) in three different ecosystems: a degraded pasture, a secondary forest and an area in recovery process using native tree seedlings. The objective was to verify the use of those insects as a tool to check the local conservation by examining Shannon's diversity index. Ten subfamilies were identified, and Microgastrinae was predominant in a number of individuals. The diversity index calculated varies among the sampled areas, thus showing a correlation with vegetation cover with the number of individuals collected and number of subfamilies found. The results showed changes in the community of Braconidae, in the recovery area between the first and second year of study, thereby leading to the conclusion that they are indicators of environmental quality.


Este estudo amostrou a diversidade de Braconidae (Hymenoptera) em três ecossistemas distintos: pastagem degradada, mata secundária e área em processo de recuperação com utilização de mudas de árvores nativas. O objetivo foi verificar a possibilidade de utilização desse grupo de insetos como ferramenta para identificar o estado de conservação local por meio da análise do índice de diversidade de Shannon. Foram identificadas dez subfamílias, com predominância em número de indivíduos de Microgastrinae. Os índices de diversidade calculados permitiram diferenciar as áreas amostradas, apresentando uma correlação da cobertura vegetal com o número de indivíduos coletados e o numero de subfamílias encontradas. O método evidenciou alteração na comunidade de Braconidae na área em recuperação, entre o primeiro e o segundo ano de estudo, demonstrando que são insetos indicadores de qualidade ambiental.

17.
Rev. biol. trop ; Rev. biol. trop;59(4): 1805-1812, Dec. 2011. graf, tab
Artigo em Espanhol | LILACS | ID: lil-646553

RESUMO

The orchid community in the Biosphere Reserve Sierra del Rosario, Cuba. The Biosphere Reserve Sierra del Rosario is located in Western Cuba and two different areas can be characterized: one for tourism and forestry activities, El Taburete (ET), and the other for conservation and research, El Salón (ES). With the aim to know the effect of visitation activities on the orchid community in the Reserve, a comparative study between the disturbed area and the preserved one was undertaken. The field work, held between 2004-2005, consisted on four transects in each locality (10x100m, 0.1ha). For each transect, the existing orchid species (terrestrial and epiphytic), kind of phorophytes, and level of occupation were identified. Different analysis were considered: dominance-diversity, Sorensen similarity, the dominance index and the relative abundance of the most abundant species. Our results showed 27 phorophytes species, 20 species in ET (98 phorophytes), and 16 species in ES (76 phorophytes). A total of 22 genus, 26 species and 8 326 individuals of orchids were identified. In ET, 17 genus, 18 species and 5 075 individuals were found, while for ES were 15 genus, 18 species and 3 251 individuals. Both locations have a similarity of species of 57.14%. Oeceoclades maculata, an invasive species, was the most abundant. The most dominant species were Microchilus plantagineus in ES and O. maculata in ET. The dominance in ET was of 81.79%, while in ES of 69.27%. It is important to sketch management plans focused on controlling O. maculata in both areas, and the restoration of the disturbed area. Rev. Biol. Trop. 59 (4): 1805-1812. Epub 2011 December 01.


Teniendo en cuenta la escasez de estudios previos que permitan apreciar el efecto de la antropización sobre las comunidades de orquídeas en la Reserva de la Biosfera Sierra del Rosario, al occidente de Cuba; se procedió a realizar un estudio comparativo entre un hábitat conservado (El Salón; ES) y uno antropizado (El Taburete; ET) y se encontraron en total 27 especies de forófitos, 20 especies presentes en ET (98 forófitos) y 16 especies en ES (76 forófitos). Por lo tanto se identificaron 22 géneros de orquídeas, 26 especies y 8 326 plantas. En ES fueron 15 géneros, 18 especies y 3 251 plantas, en ET, 17 géneros, 18 especies y 5 075 plantas. Oeceoclades maculata, una especie invasora, fue la más abundante. Ambas localidades tienen una similaridad de especies de 57.14%. Las especies más dominantes fueron: Microchilus plantagineus en ES y O. maculata en ET. La dominancia en ES es de 69.27% y en ET de 81.79%. Es importante elaborar planes de manejo enfocados a controlar O. maculata en ambas áreas, y en restablecer el estrato arbóreo original de la zona antropizada.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Orchidaceae/classificação , Árvores , Cuba
18.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;43(5): 516-522, set.-out. 2010. ilus, tab
Artigo em Inglês | LILACS, Sec. Est. Saúde SP | ID: lil-564286

RESUMO

INTRODUCTION: Study of the temporal activity of malaria vectors during the implantation of a hydroelectric power station on the River Paraná, intended to generate electrical energy. The river separates the States of São Paulo and Mato Grosso do Sul, in Brazil. The objective was to verify whether alterations occurred in the wealth and diversity indices of Anopheles, following two successive floods, extended to the temporal activity and nycthemeral rhythm followed over a five year period. METHODS: Mosquito capture was performed monthly using the Human Attraction Technique and Shannon Traps. The first, executed for 24h, provided the nycthemeral rhythm and the second, lasting 15h, permitted the tracking of Anopheles during the two floods. RESULTS: The bimodal pattern of Anopheles darlingi defined before these floods was modified throughout the environment interventions. The same effect had repercussions on the populations of An albitarsis s.l., An triannulatus and An galvaoi. Activity prior to twilight was less affected by the environment alterations. CONCLUSIONS: The dam construction provoked changes in Anopheles temporal activity patterns, permitting classification of the area as an ecologically steady and unstable situation. Differences observed in Anopheles behavior due to the capture methods revealed the influence of solo and multiple attractiveness inside the populations studied.


INTRODUÇÃO: Estudo da atividade horária de vetores da malária durante a implantação de uma represa no Rio Paraná, destinada à geração de energia elétrica. O rio separa os Estados de São Paulo e Mato Grosso do Sul, no Brasil. O objetivo foi verificar se as alterações na riqueza e diversidades de Anopheles diante de duas inundações sucessivas se estendiam à atividade horária e ritmo nictimeral numa série temporal de cinco anos. MÉTODOS: A captura de mosquito foi mensal, por meio dos métodos Técnica Atrativa Humana e Armadilha de Shannon. A primeira, executada durante 24 horas, forneceu o ritmo nictimeral e a segunda, com duração de 15 horas, para acompanhar os anofelinos durante as duas inundações. RESULTADOS: O padrão bimodal de Anopheles darlingi definido antes dessas inundações foi alterado ao longo das intervenções ambientais. O mesmo efeito repercutiu nas populações de An albitarsis s.l., An triannulatus e An galvaoi. A atividade pré-crepuscular foi a menos afetada pelas alterações ambientais. CONCLUSÕES: As barragens provocam mudanças no padrão de atividade horária dos anofelinos permitindo classificar a área em situação ecologicamente estável e instável. Diferenças observadas no comportamento dos anofelinos pelos métodos de captura mostram a influência da uni e múltipla atratividade dentro das populações estudadas.


Assuntos
Animais , Anopheles/fisiologia , Biodiversidade , Ritmo Circadiano/fisiologia , Inundações , Insetos Vetores/fisiologia , Centrais Elétricas , Anopheles/classificação , Brasil , Densidade Demográfica , Dinâmica Populacional
19.
Rev. bras. entomol ; Rev. bras. entomol;54(1): 76-81, mar. 2010. ilus, tab
Artigo em Português | LILACS | ID: lil-550500

RESUMO

Diversidade de formigas epigéicas (Hymenoptera, Formicidae) em ambientes no Centro-Oeste do Brasil. Foi comparada, através do uso de índices de diversidade e modelos de abundância de espécies, a diversidade das comunidades de formigas epigéicas que ocorrem em duas estruturas vegetacionais diferentes: mata nativa e cultura de eucalipto. Para a captura das formigas foram utilizadas 800 armadilhas de solo do tipo pitfall, em oito amostras distintas. Um total de 85 espécies, distribuídas em 36 gêneros de sete subfamílias foram coletadas nos dois ambientes, sendo que destas, 83 ocorreram na mata nativa e 60 na cultura de eucalipto. A diversidade de espécies de formigas calculada pelo índice de Simpson não foi significativamente diferente entre os ambientes, ao contrário do resultado obtido a partir da aplicação do índice de Shannon, o qual indicou maior diversidade de espécies na mata nativa. O modelo log-series não se ajustou satisfatoriamente aos dados das comunidades de formigas encontradas na cultura de eucalipto e na mata nativa, mas o modelo log-normal mostrou-se adequado para descrever a estrutura das comunidades dos dois ambientes. O modelo broken-stick, que representa uma comunidade bem estruturada, ajustou-se apenas aos dados da mata nativa.


We compared, through the use of diversity indices and species abundance models, the diversity of communities of epigeous ants occurring in two different vegetational structures: native forest and eucalyptus plantation. To capture the ants, 800 soil pitfall traps were used, in eight sample series. A total of 85 species, belonging to 36 genera of seven subfamilies were collected in the two environments. Of these species, 83 occurred in the native forest and 60 in the eucalyptus plantation. The species diversity as evaluated by Simpson's index was not significantly different between the environments, but the Shannon index indicated a higher diversity of species in the native forest. The log-series model could not be adjusted satisfactorily to the data for the ant communities from either the eucalyptus plantation or the native forest; however, the log-normal model appeared appropriate to describe the community structure in both environments. The broken-stick model, which represents a well-structured community, was only adjusted to the data for the native forest sites.

20.
Rev. bras. entomol ; Rev. bras. entomol;51(1): 67-71, jan.-mar. 2007. tab
Artigo em Português | LILACS | ID: lil-450108

RESUMO

Diversity of Scarabaeidae s. str. (Coleoptera) in the Reserva Biológica Guaribas, Mamanguape, Paraiba, Brazil: a comparison between Atlantic Forest and northeast's Tabuleiro. Scarabaeid beetles consume dung and carcasses of large vertebrates. Guilds of scarabeids were compared between Forest and Tabuleiro at the Reserva Biológica Guaribas, Mamanguape, in the state of Paraíba. Samples were collected monthly from November 2001 to April 2002 in Forest and Tabuleiro. Insects were collected by using 24 pitfall-traps, 12 in each area, with six traps baited with human excrement and six with rotten liver. Fifteen species and 1298 specimens were collected in the Forest and 25 species and 2235 specimens in the Tabuleiro. Eleven species occurred in both areas, whereas 14 were found only in the Tabuleiro and four in the Forest. Dichotomius sericeus (Harold, 1867) was the most abundant species in the two areas. The Tabuleiro was the most species-rich; however dominance was greatest in the Forest. The presence of common species in the two studied areas confers a moderate similarity to the forest and Tabuleiro habitats.


Os Scarabaeidae consomem fezes e carcaças de grandes vertebrados. Comunidades de escarabeídeos foram comparadas entre áreas de Mata e Tabuleiro da Reserva Biológica Guaribas, Mamanguape, Paraíba. As amostragens foram realizadas mensalmente durante o período de Novembro/2001 a Abril/2002 em áreas de Tabuleiro e Mata. Para coleta dos insetos foram utilizadas 24 armadilhas pitfall iscadas, 12 em cada área, sendo seis iscadas com fezes humanas e seis com fígado apodrecido. Na área de Mata foram coletados 15 espécies e 1298 indivíduos. Na área de Tabuleiro, 25 espécies e 2235 indivíduos. Onze espécies ocorrem conjuntamente nos dois ambientes, sendo 14 registradas apenas para o Tabuleiro e 4 para a Mata. Dichotomius sericeus (Harold, 1867) foi a espécie mais abundante nas duas áreas. A área de Tabuleiro apresentou maior riqueza, entretanto a Mata apresentou maior dominância. O compartilhamento de espécies comuns entre a Mata e o Tabuleiro confere a estes ambientes similaridade moderada.


Assuntos
Animais , Besouros , Biodiversidade , Brasil , Ecologia
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