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1.
Braz. j. biol ; 84: e259137, 2024. graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1364510

RESUMEN

The edge effect has impacts on seed and seedling survival due to modifications in biotic and abiotic factors. Often, large-seeded tree species lost seed vectors in the forest edge due to the rarity or absence of large frugivores at this habitat type. In this study, I compared the seedling abundance and distribution of the palm Syagrus flexuosa between edges and interiors of three large Cerrado remnants. In every remnant, the number of seedlings around parent palms in the edge was smaller than around palm individuals located in the Cerrado interior. Moreover, the distribution of seedlings around parent palms differed between edges and interiors. In the edges, most seedlings were found under parent crowns, while in the interiors, the contrary occurred. The high concentration of seedlings under parent palms suggests a decrease of seed dispersal at the edges. Because S. flexuosa is a widely distributed palm that serves as an important resource for several animals along Cerrado habitats, changes on the regeneration process of this palm due to edge effects can further impact frugivore populations. Therefore, the decline of seedling establishment along forest edges implies changes in the Cerrado regeneration dynamics, which may compromise the persistence of ecological processes and animal communities.


O efeito de borda tem impactos severos na sobrevivência de sementes e plântulas devido a modificações dos fatores bióticos e abióticos. Frequentemente, espécies arbóreas com sementes grandes perdem seus dispersores na borda da floresta devido à raridade ou ausência de grandes frugívoros neste tipo de habitat. Neste estudo, comparei a abundância e distribuição de plântulas de S. flexuosa entre bordas e interiores de três grandes remanescentes de Cerrado. Em cada remanescente, o número de plântulas ao redor das palmeiras-mãe, na borda, era menor do que ao redor dos indivíduos no interior do Cerrado. Nas bordas, a maioria das plântulas foi encontrada junto às plantas mãe, enquanto no interior ocorreu o contrário. A alta concentração de plântulas sob as plantas adultas sugere diminuição da dispersão de sementes nas bordas. Como S. flexuosa é uma palmeira amplamente distribuída que serve como um recurso importante para vários animais nos habitats do Cerrado, mudanças no processo de regeneração dessa palmeira devido aos efeitos de borda podem impactar ainda mais as populações de frugívoros. Portanto, o declínio do estabelecimento de plântulas ao longo das bordas do Cerrado implica em mudanças na dinâmica de regeneração do Cerrado, o que pode comprometer a persistência de processos ecológicos e comunidades animais.


Asunto(s)
Ecosistema , Arecaceae , Plantones , Dispersión de Semillas
2.
Braz. j. biol ; 84: e256160, 2024. tab, graf, mapas, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1360203

RESUMEN

Riverine forests are unique and highly significant ecosystems that are globally important for diverse and threatened avian species. Apart from being a cradle of life, it also serves as a gene pool that harbors a variety of flora and fauna species (repeated below). Despite the fact, this fragile ecosystem harbored avian assemblages; it is now disappearing daily as a result of human activity. Determining habitat productivity using bird species is critical for conservation and better management in the future. Multiple surveys were conducted over a 15-month period, from January to March 2019, using the distance sampling point count method. A total of 250 point count stations were fixed systematically at 300 m intervals. In total, 9929 bird individuals were recorded, representing 57 species and 34 families. Out of 57 bird species, two were vulnerable, one was data deficient, one was nearly threatened, and the remaining 53 species were of least concern. The Eurasian Collard Dove - Streptopelia decaocto (14.641 ± 2.532/ha), White-eared Bulbul - Pycnonotus leucotis (13.398 ± 4.342/ha) and Common Babbler - Turdoides caudata (10.244 ± 2.345/ha) were the three first plenteous species having higher densities. However, the densities of three species, i.e., Lesser Whitethroat - Sylvia curruca, Gray Heron - Ardea cinerea and Pallas Fish Eagle - Haliaeetus leucoryphus, were not analyzed due to the small sample size. The findings of diversity indices revealed that riverine forest has harbored the diverse avian species that are uniformly dispersed across the forest. Moreover, recording the ten foraging guilds indicated that riverine forest is rich in food resources. In addition, the floristic structure importance value index results indicated that riverine forest is diverse and rich in flora, i.e. trees, shrubs, weeds and grass, making it an attractive and productive habitat for bird species.


As florestas ribeirinhas são ecossistemas únicos e altamente significativos que são globalmente importantes para diversas espécies de aves ameaçadas de extinção. Além de serem o berço da vida, também servem como um conjunto genético que abriga uma variedade de espécies da flora e da fauna. Apesar disso, esse frágil ecossistema abrigava um conjunto de aves, mas agora está desaparecendo diariamente como resultado da atividade humana. Determinar a produtividade do hábitat usando espécies de pássaros é fundamental para a conservação e melhor gestão no futuro. Vários levantamentos foram realizados ao longo de um período de 15 meses, de janeiro de 2018 a março de 2019, por meio do método de contagem de pontos de amostragem de distância. Foram fixadas sistematicamente 250 estações de contagem de pontos em intervalos de 300 m. No total, foram registrados 9.929 indivíduos de aves, representando 57 espécies e 34 famílias. Das 57 espécies de aves, duas eram vulneráveis, uma tinha dados insuficientes, uma estava quase ameaçada e as 53 espécies restantes eram as menos preocupantes. O: Pomba de colar euroasiática - Streptopelia decaocto (14.641 ± 2.532/ha), o Bulbul de orelha branca - Pycnonotus leucotis (13.398 ± 4.342/ha) e Tagarela comum - Turdoides caudata (10.244 ± 2.345/ha) foram as três primeiras espécies abundantes com maiores densidades. No entanto, as densidades de três espécies, Papa-amoras-cinzento (Sylvia curruca), Garça-real-europeia (Ardea cinerea) e Águia-pescadora de Pallas (Haliaeetus leucoryphus), não foram analisadas por causa do pequeno tamanho da amostra. Os resultados dos índices de diversidade revelaram que a floresta ribeirinha abrigou diversas espécies de aves que estão uniformemente dispersas pela floresta. Além disso, o registro das dez guildas de forrageamento indicou que a floresta ribeirinha é rica em recursos alimentares. Além disso, os resultados do índice de valor de importância da estrutura florística indicaram que a floresta ribeirinha é variada e rica em flora, ou seja, árvores, arbustos, ervas daninhas e grama, tornando-a um hábitat atraente e produtivo para espécies de aves.


Asunto(s)
Aves , Bosques , Ecosistema , Antecedentes Genéticos
3.
Braz. j. biol ; 84: e255950, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1364497

RESUMEN

Aquatic insect fauna remains an important tool for bio indication of environmental disturbance, while maintaining a healthy aquatic system. The purpose of the study was to document and to identify the diversity and distribution patterns of aquatic insect, a highly ignored aspect from the Qatar. Following the standard procedures, the samples were collected from aquatic habitats during the period October 2015 to May 2017 on monthly basis. A total of 11,287 individuals, belonging to 6 orders were captured. Dipterans were the abundant with the percentages of 71.01 (n=8,015), while the lowest percentage was observed for Coleoptera 0.04 (n=05). Twelve insects families were identified, among these five were reported under Diptera, followed by Hemiptera (03), while Coleoptera, Tricoptera, Odonata, and Ephemeroptera were represented by single families. Among the selected localities, Dipterans were collected from 10 stations, followed by Hemiptera (9), Coleoptera (4), Odonota (4), Ephemeroptera (3) and Trichoptera (1) respectively. Among the water bodies samples, streams were the most preferred habitats (n=2,767), while drinking water pools were the least (27). Moreover, the highest Simpson diversity index of 1.48 and lowest of 0.47 was recorded for flooded sewage pool and plastic containers respectively, while the low evenness values were observed for ponds, and less than 1 Margalef's diversity values were seen for all habitats. This study documents the patterns of the diversity and distribution of aquatic insects, and provides a baseline for the future studies from Qatar.


A fauna aquática de insetos continua sendo uma ferramenta importante para a bioindicação de distúrbios ambientais, ao mesmo tempo em que mantém um sistema aquático saudável. O objetivo do estudo foi documentar e identificar a diversidade e os padrões de distribuição dos insetos aquáticos, um aspecto altamente ignorado no Catar. Seguindo os procedimentos padrão, as amostras foram coletadas em hábitats aquáticos durante o período de outubro de 2015 a maio de 2017, mensalmente. Um total de 11.287 indivíduos, pertencentes a seis ordens, foram capturados. Dípteros foram os mais abundantes, com as porcentagens de 71,01 (n = 8.015), enquanto a menor porcentagem foi observada para Coleópteros 0,04 (n = 05). Doze famílias de insetos foram identificadas, destas, cinco foram registradas sob Diptera, seguido por Hemiptera (03), enquanto Coleoptera, Tricoptera, Odonata e Ephemeroptera foram representados por famílias únicas. Dentre as localidades selecionadas, Dipterans foram coletados em 10 estações, seguidos por Hemiptera (9), Coleoptera (4), Odonota (4), Ephemeroptera (3) e Trichoptera (1), respectivamente. Entre as amostras de corpos d'água, os riachos foram os hábitats mais preferidos (n = 2.767), enquanto as piscinas de água potável foram os menos (27). Além disso, o maior índice de diversidade de Simpson de 1,48 e o menor de 0,47 foi registrado para piscina de esgoto inundada e recipientes de plástico, respectivamente, enquanto os valores de baixa uniformidade foram observados para lagoas e menos de 1 valores de diversidade de Margalef foram observados para todos os hábitats. Este estudo documenta os padrões de diversidade e distribuição de insetos aquáticos e fornece uma linha de base para os estudos futuros do Catar.


Asunto(s)
Animales , Fauna Acuática , Ecosistema , Insectos
5.
Braz. j. biol ; 84: e251438, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1345560

RESUMEN

Abstract The northwestern portion of the Upper Paraná Atlantic Forest ecoregion is one of the most disturbed and fragmented areas in the Atlantic Forest, and little is known about the local avifauna. In this study, we have described the composition and diversity of the aquatic avifauna of this region and analyzed the patterns of similarity with respect to the seasonal as well as spatial distribution. We used the line transect sampling technique in six distinct humid areas (including lentic and lotic water bodies) during the dry and rainy seasons of 2012 and 2013. A total of 52 species of waterfowl were recorded. The species richness of the studied areas was surprisingly distinct; only seven waterfowl species, namely Cairina moschata (Linnaeus, 1758), Tigrisoma lineatum (Boddaert, 1783), Rosthramus sociabilis (Vieillot, 1817), Aramus guarauna (Linnaeus, 1766), Vanellus chilensis (Molina, 1782), Jacana jacana (Linnaeus, 1766), and Arundinicola leucocephala (Linnaeus, 1764), were common to these six studied areas. This indicated that the other bird species that were observed might be habitat selective. Moreover, the analysis of the composition of birds in the two seasons (dry and rainy) combined with their spatial distributions showed significant dissimilarities between the areas with lotic (river and constructed wetland) and lentic (lagoons) characteristics. Nevertheless, despite the small extent and low total richness of the entire study area, it was found to be home to 1/3 of all freshwater aquatic birds documented in the state of São Paulo, with the record of 5 migratory species and 11 new species added to the northwest of the state. The heterogeneity of local aquatic environments, habitat selection combined with seasonality, and the absence of other humid locations in the surroundings can explain the diversity and distribution of these birds in the water bodies of this uninvestigated Atlantic Forest ecoregion.


Resumo A porção noroeste da ecorregião Floresta Atlântica do Alto Paraná é uma das mais alteradas e fragmentadas da Mata Atlântica, da qual pouco se sabe sobre a avifauna local. Nosso objetivo foi descrever a diversidade e composição da avifauna aquática, bem como analisar os padrões de similaridade quanto a distribuição temporal e espacial destas aves nesta ecorregião. Utilizamos a transecção linear para amostragem em seis áreas úmidas (corpos d'água lênticos e lóticos), nos períodos de seca e chuva entre 2012 e 2013. Registramos 52 espécies de aves aquáticas e as riquezas das áreas mostraram-se distintas, pois apenas Cairina moschata (Linnaeus, 1758), Tigrisoma lineatum (Boddaert, 1783), Rosthramus sociabilis (Vieillot, 1817), Aramus guarauna (Linnaeus, 1766), Vanellus chilensis (Molina, 1782), Jacana jacana (Linnaeus, 1766), and Arundinicola leucocephala (Linnaeus, 1764) foram comuns às seis áreas, o que indica seleção de habitat. Quando analisada a composição das aves nos dois períodos aliada à distribuição espacial, encontramos dissimilaridades temporais acentuadas entre os ambientes com características lóticas (rio e aterro) e lênticas (lagoas). Isto mostra que, além das diferentes épocas sazonais, é necessário analisar separadamente os diferentes tipos de áreas úmidas. Por fim, apesar da extensão pequena e baixa riqueza total, a área amostrada abrigou 1/3 das aves aquáticas de água doce para o estado de São Paulo, cinco espécies migratórias e 11 novas espécies para o noroeste do estado. A heterogeneidade de ambientes aquáticos locais, forte seleção de habitat aliada à sazonalidade e ausência de outros locais úmidos em seu entorno, explicam a diversidade e distribuição destas aves estreitamente relacionadas aos corpos d'água desta desconhecida ecorregião da Mata Atlântica.


Asunto(s)
Animales , Aves , Biodiversidad , Estaciones del Año , Brasil , Bosques , Ecosistema
6.
Braz. j. biol ; 84: e251197, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1350305

RESUMEN

Abstract Birds are among the best bio-indicators, which can guide us to recognize some of the main conservation concerns in ecosystems. Anthropogenic impacts such as deforestation, habitat degradation, modification of landscapes, and decreased quality of habitats are major threats to bird diversity. The present study was designed to detect anthropogenic causative agents that act on waterbird diversity in Tarbella Dam, Indus River, Pakistan. Waterbird censuses were carried out from March 2019 to February 2020 in multiple areas around the dam. A total of 2990 waterbirds representing 63 species were recorded. We detected the highest waterbird richness and diversity at Pehure whereas the highest density was recorded at Kabbal. Human activity impacts seemed to be the main factor determining the waterbird communities as waterbirds were negatively correlated with the greatest anthropogenic impacts. Waterbirds seem to respond rapidly to human disturbance.


Resumo As aves estão entre os melhores bioindicadores, o que pode nos orientar a reconhecer algumas das principais preocupações de conservação dos ecossistemas. Impactos antrópicos como desmatamento, degradação de habitat, modificação de paisagens e diminuição da qualidade dos habitats são as principais ameaças à diversidade de aves. O presente estudo foi desenhado para detectar agentes causadores antropogênicos que atuam na diversidade de aves aquáticas na Represa de Tarbella, rio Indus, Paquistão. Censos de aves aquáticas foram realizados de março de 2019 a fevereiro de 2020 em várias áreas ao redor da barragem. Um total de 2.990 aves aquáticas representando 63 espécies foi registrado. Detectamos a maior riqueza e diversidade de aves aquáticas em Pehure, enquanto a maior densidade foi registrada em Kabbal. Os impactos da atividade humana parecem ser o principal fator determinante das comunidades de aves aquáticas, uma vez que as aves aquáticas foram negativamente correlacionadas com os maiores impactos antrópicos. As aves aquáticas parecem responder rapidamente às perturbações humanas.


Asunto(s)
Humanos , Ecosistema , Ríos , Pakistán , Conservación de los Recursos Naturales
7.
Braz. j. biol ; 84: e255485, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1350312

RESUMEN

Abstract The current focus is on the overall pattern of seed storage present in the fragments of the soil of piedmont and alluvial landscapes of the environment. The present study predicted the seed banks of both soils of alluvial and piedmont zones in different ecological conditions and evaluate the potential of seeds in the restoration of both environments. The composition of the seed bank of soil is mainly affected by the alluvial environment and the structure of cleared area shows that more species of germinating annual grasses and growable seeds with the higher total number. Extant vegetation structures have an important role in the diversity of soil seed reservoirs, whose composition corresponded with the openness of the site. When in situ soil seed bank is recruited, it helps to restore only some components of the plant community in an alluvial environment. In our current research, it was confirmed that seed richness was higher in number at lower elevation (alluvial) than that at high elevation (piedmont). Seed richness showed a significant negative correlation with anions, cations, while significantly positive with altitude that suggests the richness pattern of the overall seed bank of the area is influenced by various environmental factors.


Resumo O foco atual está no padrão geral de armazenamento de sementes presente nos fragmentos de solo do Piemonte e nas paisagens aluviais do meio ambiente. O presente estudo previu os bancos de sementes de ambos os solos das zonas aluvial e piemontesa em diferentes condições ecológicas e avaliou o potencial das sementes na restauração de ambos os ambientes. A composição do banco de sementes do solo é afetada principalmente pelo ambiente aluvial e a estrutura da área desmatada mostra que mais espécies de gramíneas anuais em germinação e sementes cultiváveis ​​apresentam o maior número total. As estruturas da vegetação existente têm um papel importante na diversidade dos reservatórios de sementes do solo, cuja composição correspondeu à abertura do local. Quando o banco de sementes do solo in situ é recrutado, o mesmo ajuda a restaurar apenas alguns componentes da comunidade de plantas em um ambiente aluvial. Em nossa pesquisa atual, foi confirmado que a riqueza de sementes era maior em número em altitudes mais baixas (aluviais) do que em altitudes elevadas (Piemonte). A riqueza de sementes mostrou uma correlação negativa significativa com ânions, cátions, enquanto significativamente positiva com a altitude, o que sugere que o padrão de riqueza do banco geral de sementes da área é influenciado por vários fatores ambientais.


Asunto(s)
Suelo , Banco de Semillas , Pakistán , Plantas , Semillas , Ecosistema , Poaceae
8.
Braz. j. biol ; 84: e253598, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355857

RESUMEN

Abstract Caryocar brasiliense Camb. (Malpighiales: Caryocaraceae) trees are widely distributed throughout the Cerrado ecosystem. The fruits of C. brasiliense trees are used by humans for food and as the main income source in many communities. C. brasiliense conservation is seriously threatened due to habitat loss caused by the land-use change. Sucking insects constitute an important ecological driver that potentially impact C. brasiliense survival in degraded environments. In addition, insects sampling methodologies for application in studies related to the conservation of C. brasiliense are poorly developed. In this study, sucking insects (Hemiptera) and their predators were recorded in three vertical strata of Caryocar brasiliense canopies. The distribution of sucking species showed vertical stratification along the canopy structure of C. brasiliense. The basal part of the canopy had the highest numbers of sucking insects Aphis gossypii (Glover 1877) (Hemiptera: Aphididae) and Bemisia tabaci (Genn. 1889) (Hemiptera: Aleyrodidae), and their predators Chrysoperla sp. (Neuroptera: Chrysopidae), spiders (Araneae), and Zelus armillatus (Lep. & Servi., 1825) (Hemiptera: Reduviidae). Predators' distribution follows the resource availability and preferred C. brasiliense tree parts with a higher abundance of prey.


Resumo Caryocar brasiliense Camb. (Malpighiales: Caryocaraceae) é amplamente distribuído por todo o ecossistema de cerrado. Os frutos de C. brasiliense são utilizados na alimentação humana e constitui uma importante fonte de renda para muitas comunidades. A perda de habitat provocada pelas mudanças de uso da terra coloca em risco a conservação de C. brasiliense. Insetos sugadores constituem um importante fator ecológico que, potencialmente, afeta o fitness de C. brasiliense em ambientes degradados. Além disso, as metodologias de amostragem de insetos para aplicação em estudos relacionados à conservação de C. brasiliense são pouco desenvolvidas. Neste estudo, o número de insetos sugadores (Hemiptera) e seus predadores foram avaliados em três estratos verticais do dossel de C. brasiliense. A distribuição das espécies sugadoras apresentou estratificação vertical ao longo da estrutura do dossel. O estrato basal do dossel apresentou o maior número de insetos sugadores Aphis gossypii (Glover 1877) (Hemiptera: Aphididae) e Bemisia tabaci (Genn. 1889) (Hemiptera: Aleyrodidae), e seus predadores Chrysoperla sp. (Neuroptera: Chrysopidae), aranhas (Araneae) e Zelus armillatus (Lep. & Servi., 1825) (Hemiptera: Reduviidae). Os predadores distribuíram-se de acordo com a disponibilidade de recursos, ocorrendo em maior número nas partes do dossel com maior abundância de suas presas.


Asunto(s)
Humanos , Animales , Áfidos , Malpighiales , Árboles , Ecosistema , Insectos
9.
Braz. j. biol ; 84: e254095, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355860

RESUMEN

Abstract In northern central Chile, ephemeral pools constitute shallow isolated water bodies with a favourable habitat for fauna adapted to seasonal changes. Based on the limited knowledge about the fauna—particularly insects—associated to these ecosystems, the objective of this study was to characterize the richness, composition, structure and similarity of the insect communities associated with ephemeral pools in Huentelauquén (29º S, Coquimbo Region, Chile). By using pitfall traps, 10,762 individuals were captured, represented by 7 orders, 27 families, and 51 species. Coleoptera and Hymenoptera were the best represented orders, with Neuroptera, Orthoptera and Plecoptera being poorly represented groups. The non-parametric estimators evaluated showed wealth values above those observed for all the studied pools, and their accumulation curves suggest the existence of an incomplete species inventory in the studied community. Additionally, the hierarchical and ordering analysis showed groupings of pools located in the northwest and southeast of Huentelauquén. Preliminarily we found a negative correlation between the area of the pools and the richness (species) and abundance of insects. Additional studies (on other arthropod groups and other seasons of the year) could provide a better understanding of the local processes of extinction and colonization of the species inhabiting these fragile coastal environments.


Resumo No norte central do Chile, lagoas efêmeras constituem corpos de água isolados e pouco profundos, com um habitat favorável para a fauna adaptada as mudanças sazonais que as zonas úmidas estão sujeitas. Com relação a estes ecossistemas, sabe-se pouco sobre sua fauna, principalmente a de insetos. O objetivo do presente estudo foi caracterizar a riqueza, composição, estrutura e similaridade das comunidades de insetos que habitam as lagoas temporárias de Huentelauquén (29º S, Região de Coquimbo, Chile). Usando armadilhas de interceptação, se capturou um total de 10.762 indivíduos, pertencentes a 7 ordens, 27 famílias e 51 espécies. Coleoptera e Hymenoptera foram as ordens mais representativas, enquanto Neuroptera, Orthoptera e Plecoptera foram grupos pouco representativos. Os estimadores não paramétricos avaliados mostraram valores de riqueza superiores ao observados para todas as lagoas estudadas, e suas curvas de acumulação parecem indicar que o inventario da comunidade estudada está incompleto. A análise hierárquica e de ordenamento revelou agrupamentos de lagoas correspondentes a zona nordeste e sudeste de Huentelauquén. Preliminarmente encontramos uma correlação negativa entre a área de lagoas efêmeras e a riqueza (espécies) e abundância de insetos. É necessário realizar estudos adicionais (sobre outros grupos de artrópodes e em outras estações do ano) para melhor compreensão dos processos locais de extinção e colonização das espécies que habitam estes frágeis ambientes costeiros estudados.


Asunto(s)
Humanos , Animales , Escarabajos , Ecosistema , Estaciones del Año , Chile , Biodiversidad , Insectos
10.
Braz. j. biol ; 84: e251410, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355887

RESUMEN

Abstract Dietary habits of bandicoot rats (bandicota bengalensis) were investigated in the agricultural crops of the Pothwar Plateau, Pakistan by analysing stomach contents. The research activities were conducted in major field crops including wheat-groundnut and in the fallow lands during non-crop season at the field boundaries. The specimens were captured from the fields using kill/snap traps, and dissected to collect their stomach samples for laboratory analysis. Light microscopic slides of the plant material were recovered from stomach samples and the reference materials were collected from the field. Results revealed that the bandicoot rat predominantly fed upon cultivated crops during cropping season but consumed wild vegetation during non-cropping season. There was no significance difference between summer and winter diets. Most frequently consumed crop food items were wheat (Triticum aestivum; 28.57%), groundnut (Arachis hypogea; 11.26%), sorghum (Sorghum bicolor; 10.17%), chickpea (Cicer arietinum; 9.52%), maize (Zea mays; 6.49%), millet (Pennisetum glaucum; 5.84%), barley (Hordeum vulgare; 4.98%) and mustard (Brassica campestris; 4.98%). Among wild vegetation were consumed khbal gha (Cynodon dactylon; 7.79%), baron dhab (Demostachya bipinnata; 7.36%) and Prickly flower (Achyranthes aspera; 3.03%). The study concludes that, in addition to consuming wheat and groundnut crops, the Lesser bandicoot rat also subsists on grasses, weeds, and some fodder crops, as important component of its diet in agro-ecosystem of the Pothwar Plateau.


Resumo Os hábitos alimentares de ratos bandicoot (Bandicota bengalensis) foram investigados nas plantações agrícolas do planalto de Pothwar, Paquistão, por meio da análise do conteúdo estomacal. As atividades da pesquisa foram conduzidas nas principais culturas de campo, incluindo trigo e amendoim, e em terras de pousio durante a estação não agrícola nos limites do campo. Os espécimes foram capturados dos campos usando armadilhas kill/snap e dissecados para coletar suas amostras de estômago para análise laboratorial. Lâminas de microscopia de luz do material vegetal foram recuperadas de amostras de estômago; os materiais de referência foram coletados no campo. Os resultados revelaram que o rato bandicoot alimentava-se predominantemente de culturas cultivadas durante a época de cultivo, mas consumia vegetação selvagem durante a época de não colheita. Não houve diferença significativa entre as dietas de verão e inverno. Os alimentos agrícolas mais frequentemente consumidos foram trigo (Triticum aestivum; 28,57%), amendoim (Arachis hypogea; 11,26%), sorgo (Sorghum bicolor; 10,17%), grão de bico (Cicer arietinum; 9,52%), milho (Zea mays; 6,49%), milheto (Pennisetum glaucum; 5,84%), cevada (Hordeum vulgare; 4,98%) e mostarda (Brassica campestris; 4,98%). Entre a vegetação silvestre foram consumidos khbal gha (Cynodon dactylon; 7,79%), barão dhab (Demostachya bipinnata; 7,36%) e flor espinhosa (Achyranthes aspera; 3,03%). O estudo conclui que, além de consumir culturas de trigo e amendoim, o rato bandicoot pequeno também subsiste de gramíneas, ervas daninhas e algumas culturas forrageiras, componentes importantes de sua dieta no agroecossistema do planalto de Pothwar.


Asunto(s)
Animales , Ecosistema , Murinae , Pakistán , Productos Agrícolas , Zea mays , Conducta Alimentaria
11.
Braz. j. biol ; 84: e251566, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355890

RESUMEN

Abstract The Seybouse is the second largest river basin in Algeria, hosting an important biodiversity and providing various ecosystem services. This watershed is highly influenced by agricultural and industrial activities, which threaten its biodiversity and ecosystem integrity. The use of benthic macroinvertebrates as biological indicators has a long tradition in developed countries and integrated into all assessments of the ecological quality of river systems. However, the macroinvertebrates of many North African regions are still not well studied, including those of the Seybouse river. The aim of this study is to assess the inventory and ecological role of benthic macroinvertebrates in inland waters of the Seybouse River and determine the impact of pollution on their spatial distributions. We sampled the benthic macrofauna of Wadi Seybouse and its affluents using regular surveys in three sites, of which one was in the upper Seybouse Bouhamdane in Medjez Amar and two in the middle Seybouse. Between December 2019 and May 2020, 10 physico-chemical parameters (pH, EC, OD, water speed, NO3, Salinity, NO2, MES, turbidity, depth) were measured in order to establish a health state diagnosis of these aquatic ecosystems. The complementary biological approach by the analysis of populations of macroinvertebrates identified 7482 individuals and 40 taxa divided into five classes: Crustaceans which were the most dominant, insects with the main orders (Ephemeroptera, Diptera, Trichoptera, Heteroptera and Odonata), Molluscs, Nematodes and Annelids. The physico-chemical analyzes and the application of the organic pollution indices indicated a strong to excessive pollution for all sites, especially in Seybouse upstream


Resumo O Seybouse é um rio no nordeste da Argélia, é o segundo maior rio, tem uma área de captação de cerca de 6.500 km2 que acolhe cerca de 1,5 milhões de habitantes. Importantes atividades agrícolas e industriais são desenvolvidas nesta bacia hidrográfica. O uso de macroinvertebrados bentônicos como indicadores biológicos tem uma longa tradição em países desenvolvidos e está integrado em todas as avaliações da qualidade ecológica dos sistemas fluviais. O objetivo deste estudo foi revisar o inventário e o papel ecológico dos macroinvertebrados bentônicos nas águas interiores do rio Seybouse e determinar o impacto da poluição em suas distribuições. Resultados semelhantes foram relatados para outros países e rios argelinos. Este estudo enfoca a macrofauna bentônica de Wadi Seybouse e seus afluentes. Foram prospectados 03 locais, um no alto Seybousse Bouhamdane em Medjez Amar e dois no meio Seybousse Salah Salah Salah e Oued Zimba. Entre dezembro de 2019 e maio de 2020, dez parâmetros físico-químicos (pH, CE, DO, velocidade da água, NO3, Salinidade, NO2, MES, turbidez, deth) foram medidos para estabelecer um diagnóstico do estado de saúde desses ecossistemas aquáticos. A abordagem biológica complementar pela análise de populações de macroinvertebrados identificou 7.482 indivíduos e 40 táxons divididos em cinco classes: Crustáceos que são os mais dominantes, Insetos com as ordens principais (Ephemeroptera, Diptera, Trichoptera, Heteroptera e Odonata), Moluscos, Nematóides e Anelídeos. As análises físico-químicas e a aplicação dos índices de poluição orgânica, indicaram uma poluição forte a excessiva para todos os locais especialmente Salah Salah Salah.


Asunto(s)
Humanos , Animales , Ecosistema , Invertebrados , Monitoreo del Ambiente , Biodiversidad , Ríos
12.
Braz. j. biol ; 84: e253852, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355905

RESUMEN

Abstract The aim objective of this study was to determine the trophic ecology of juvenile and adult Acestrorhynchus falcirostris during the rising and flood (high-water) period in six island lakes adjacent to the Solimões River. As such, we investigated: i) the trophic position, through the fractional trophic niche; ii) the niche breadth; iii) niche overlap and iv) the food strategy of the species. The specimens were collected during the years 2014 to 2017, using gillnets with mesh sizes ranging from 30 to 120mm between opposite knots. Through the analysis of stomach contents, the preference in the consumption of items of animal origin was observed. Juveniles consumed insects in greater proportions (IAi% = 50%), while adults consumed fish (IAi%=99,98%). Despite the large supply of food items available in the high-water period, juveniles were the only ones to consume items of allochthonous origin, such as insects. Juveniles presented a different dietary strategy and dietary composition to adults. Juveniles were omnivores with a generalist strategy, while adults were piscivores with a specialist strategy. Thus, the food composition, niche breadth, trophic position and feeding strategy of Acestrorhynchus falcirostris change due to the stage of development.


Resumo O objetivo deste estudo foi determinar a ecologia trófica de juvenis e adultos de Acestrorhynchus falcirostris durante o período de enchente e cheia em seis lagos de ilha adjacentes ao rio Solimões. Assim, investigamos: i) a posição trófica, através do nicho trófico fracional; ii) a largura de nicho; iii) sobreposição de nicho; iv) a estratégia alimentar. Os espécimes foram coletados durante os anos de 2014 a 2017, utilizando redes de emalhar com malha variando de 30 a 120mm entre nós opostos. Por meio da análise do conteúdo estomacal, observamos a preferência no consumo de itens de origem animal. Os juvenis consumiram insetos em maiores proporções (IAi% = 50%), enquanto os adultos consumiram preferencialmente peixes (IAi% = 99,98%). Apesar da grande oferta de alimentos disponíveis no período da cheia, os juvenis eram os únicos a consumir itens de origem alóctone, como por exemplo, os insetos. Os juvenis apresentaram uma estratégia alimentar e composição alimentar diferente para os adultos. Os juvenis foram considerados onívoros com uma estratégia generalista, enquanto os adultos foram considerados piscívoros com uma estratégia alimentar mais especialista. Assim, a composição alimentar, amplitude do nicho, posição trófica e a estratégia alimentar de Acestrorhynchus falcirostris muda em função do estágio de desenvolvimento.


Asunto(s)
Animales , Ríos , Characiformes , Estaciones del Año , Lagos , Ecosistema , Cadena Alimentaria , Peces , Contenido Digestivo
13.
Braz. j. biol ; 84: e254479, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355910

RESUMEN

Abstract Earias vittellaFabricius, 1794 (Noctuidae: Lepidoptera) is deliberated to be one of the most destructive pests of cotton and okra vegetation in the world including Asia. The pest has established resistance to various synthetic insecticides. The use of bio-pesticide is one of the unconventional approaches to develop a vigorous ecosystem without harming non- target pests and beneficial natural insect fauna. In the present study, the toxicity levels of Citrullus colocynthis seed extract have been evaluated against the populations of E. vittellaunder standardized laboratory conditions. The toxic effects of C. colocynthis on development periods, protein contents and esterase activity of the life stages of E. vittella were also evaluated. The toxicity levels of methanol, ethanol, hexane, water and profenofos were evaluated on the 1st instar larvae of E. vittella. LC30 and LC80 concentrations exhibited the effectiveness of methanol-based C. colocynthis seed extract against 1st instar larvae of E. vitella. The enhanced larval and pupal periods were revealed in treated samples during the comparison with untreated samples. The intrinsic rate of increase, net reproductive rate in the LC30 and LC80 concentrations exposed larvae remained less than the control treatment. Fecundity, the esterase activity and protein contents were declined in LC30 and LC80 treated samples as compared to the control. The present findings suggest that C. colosynthis extracts based botanical insecticides are beneficial, ecosystem sustainable and can be integrated with insect management programs from environment safety perspective.


Resumo Earias vittella Fabricius, 1794 (Noctuidae: Lepidoptera) é considerada uma das pragas mais destrutivas de algodão e quiabo no mundo, incluindo a Ásia. Essa praga estabeleceu resistência a vários inseticidas sintéticos. O uso de biopesticidas é uma das abordagens não convencionais para desenvolver um ecossistema saudável sem prejudicar as pragas não alvo e a fauna natural benéfica de insetos. No presente estudo, os níveis de toxicidade do extrato de semente de Citrullus colocynthis foram avaliados nas populações de E. vittella em condições de laboratório padronizadas. Os efeitos tóxicos de C. colocynthis nos períodos de desenvolvimento, conteúdo de proteína e atividade esterase das fases de vida de E. vittella também foram avaliados. Os níveis de toxicidade de metanol, etanol, hexano, água e profenofós foram avaliados em larvas de 1º instar de E. vittella. As concentrações de LC30 e LC80 apresentaram eficácia do extrato de sementes de C. colocynthis à base de metanol contra larvas de 1º instar de E. vittella. Os períodos larval e pupal aumentados foram revelados nas amostras tratadas durante a comparação com as amostras não tratadas. A taxa intrínseca de aumento e a taxa reprodutiva líquida nas concentrações de larvas expostas LC30 e LC80 permaneceram menores do que o tratamento controle. A fecundidade, a atividade da esterase e o conteúdo de proteína diminuíram nas amostras tratadas com LC30 e LC80 em comparação com o controle. As presentes descobertas sugerem que os extratos de C. colocynthis à base de inseticidas botânicos são benéficos, sustentáveis ​​para o ecossistema e podem ser integrados com programas de manejo de insetos do ponto de vista da segurança ambiental.


Asunto(s)
Animales , Citrullus colocynthis , Insecticidas , Mariposas Nocturnas , Extractos Vegetales/farmacología , Ecosistema , Larva
14.
J Theor Biol ; 556: 111314, 2023 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-36252842

RESUMEN

Models of populations in habitat networks are vital for understanding and linking processes and patterns across individuals, environments, ecological interactions, and population structures. River ecosystem models combine the physical structure of the networks with the biological processes of the organisms using structural and functional models, respectively. Previous studies on dendritic river networks have employed different functional (population) models and either directly claimed or implied that the results illustrate general properties of actual river systems. However, these studies have used different approaches and assumptions when modeling population characteristics and behavior, and it is possible that inferences regarding a system may vary based on the combination of functional model and the spatial structure of a network. This study aims to understand if different functional models in river systems produce substantially different model results and, therefore, whether conclusions are model-dependent. We compare variation in extinction time and occupancy proportion of river networks with linear, trellis, dendritic and ring-lattice topologies, using three population models (uniform, age-class and individual based) and one metapopulation-based (patch-occupancy) model. Dendritic, linear, and trellis structures did not show notable differences among extinction times for any of the four models. The difference between topologies was higher for the patch-occupancy model compared to the three population models. There were significant differences in the variations of patch-occupancy between the metapopulation and the population models, but the three population models of differing complexity produced broadly similar results. Therefore, if the occupancy data is obtained based on local subpopulations, spatial arrangement and connectivity does not appear to be the sole predictor of single-species metapopulation responses. We conclude that the outputs from functional models are robust to assumptions and varying levels of detail as long as they contain at least some detail at the level of individuals within habitat nodes. Also, if we are modeling network-scale populations, models that include at least some detailed information on individuals are a far better choice than considering populations implicitly.


Asunto(s)
Ecosistema , Modelos Biológicos , Humanos , Dinámica Poblacional , Ríos
15.
J Environ Sci (China) ; 125: 678-690, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36375949

RESUMEN

Antibiotics in soil environment are regarded as emerging pollutants and have introduced increasing risks to soil ecosystem and human health in rapid urbanization areas. Identifying the occurrence and spatial variability of antibiotics in soils is an urgent issue in sustaining soil security. In this study, antibiotics in soils were investigated and analyzed in Beijing-Tianjin-Hebei urban agglomeration. The occurrence, spatial distribution, and related affecting factors of antibiotics in soils were identified and ecological risks of antibiotics in soil environment were assessed. Results showed that (1) The mean concentration of soil antibiotics in Beijing-Tianjin-Hebei urban agglomeration was 21.79 µg/kg. Land use substantially affected the occurrence and concentration of antibiotics in soils. Concentrations of antibiotics in cropland and orchard soils were 2-3 times higher than the other land use types. (2) The concentrations of antibiotics in soils in Beijing-Tianjin-Hebei urban agglomeration presented a spatial pattern of high values in southeast, and low values in northwest. Spatial variability of antibiotics in soils was closely related to the application of organic fertilizer and wastewater irrigation as well as topographical features. Furthermore, soil properties and land management policy had substantial influences on soil antibiotics, and soil heavy metals may aggravate the accumulation of antibiotics in soils. (3) Ecological risks assessment of antibiotics in soils demonstrated that erythromycin (ERY), sulfamethoxazole (SMX), and doxycycline (DOX) may introduce high risks to soil ecosystem health, and more attention should be paid to the areas with intensive human activities that had potential high risk to soil ecosystem health. This study suggests that scientific land and soil management should be considered to prevent soil antibiotic pollution and sustain soil security in urban agglomeration.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Humanos , Suelo , Contaminantes del Suelo/análisis , Antibacterianos/análisis , Ecosistema , Metales Pesados/análisis , Aguas Residuales , China , Monitoreo del Ambiente , Medición de Riesgo
17.
Chemosphere ; 310: 136801, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36241121

RESUMEN

Fungicides containing manganese (Mn) applied to control plant diseases increase the concentration of Mn in soils, which may potentiate Mn toxicity in acid soils. Some species of wild grasses, such as those from the Pampa biome located in South America, or even those introduced into this biome, may possess different mechanisms of tolerance to excess Mn. The present study aimed to evaluate the subcellular distribution and physiological and biochemical responses of exotic and native grasses from the Pampa biome, cultivated in Mn excess. The experiment was conducted in nutrient solution in a greenhouse, in an entirely randomized design, bifactorial 4 × 4, consisting of four Mn concentrations (2 [control], 300, 600 and 900 µM) and four species (two exotic: Avena strigosa and Lolium multiflorum; and two native: Paspalum notatum and Paspalum plicatulum). At 27 days of exposure to the treatments, biomass and growth rates, leaf gas exchange with the environment, photosynthetic pigment concentrations of malondialdehyde and H2O2, antioxidant enzyme activities (SOD and POD), and subcellular distribution of Mn were evaluated. Most of the grasses showed high concentration of Mn in tissues, mainly, in the shoot. In the presence of 900 µM Mn, more than 80% of the absorbed Mn was compartmentalized in the cell walls and vacuoles of the cells. Compartmentalization of Mn excess into metabolically less active organelles is the main tolerance factor in grasses. Physiological and biochemical responses were stimulated in the presence of 300 µM Mn, while 900 µM Mn negatively affected biochemical-physiological responses of grasses. The species L. multiflorum was most sensitive to excess Mn, while P. notatum was the most tolerant.


Asunto(s)
Manganeso , Poaceae , Antioxidantes , Ecosistema , Peróxido de Hidrógeno , Manganeso/toxicidad , Suelo
18.
Biochim Biophys Acta Gen Subj ; 1867(1): 130251, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36244576

RESUMEN

CdSe/ZnS Quantum dots (QDs) are possibly released to surface water due to their extensive application. Based on their high reactivity, even small amounts of toxicant QDs will disturb water microbes and pose a risk to aquatic ecology. Here, we evaluated CdSe/ZnS QDs toxicity to Tetrahymena thermophila (T. thermophila), a model organism of the aquatic environment, and performed metabolomics experiments. Before the omics experiment was conducted, QDs were found to induce inhibition of cell proliferation, and reactive oxygen species (ROS) production along with Propidium iodide labeled cell membrane damage indicated oxidative stress stimulation. In addition, mitochondrial ultrastructure alteration of T. thermophila was also confirmed by Transmission Electron Microscope results after 48 h of exposure to QDs. Further results of metabolomics detection showed that 0.1 µg/mL QDs could disturb cell physiological and metabolic metabolism characterized by 18 significant metabolite changes, of which twelve metabolites improved and three decreased significantly compared to the control. Kyoto Encyclopedia of Genes and Genomes analysis showed that these metabolites were involved in the ATP-binding cassette transporter and purine metabolism pathways, both of which respond to ROS-induced cell membrane damage. In addition, purine metabolism weakness might also reflect mitochondrial dysfunction associated with energy metabolism and transport abnormalities. This research provides deep insight into the potential risks of quantum dots in aquatic ecosystems.


Asunto(s)
Compuestos de Cadmio , Puntos Cuánticos , Compuestos de Selenio , Tetrahymena thermophila , Puntos Cuánticos/toxicidad , Compuestos de Cadmio/toxicidad , Compuestos de Cadmio/química , Compuestos de Selenio/farmacología , Tetrahymena thermophila/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ecosistema , Estrés Oxidativo , Agua , Purinas , Lípidos
19.
Ambio ; 52(1): 15-29, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35882751

RESUMEN

The COVID-19 pandemic and related social and economic emergencies induced massive public spending and increased global debt. Economic recovery is now an opportunity to rebuild natural capital alongside financial, physical, social and human capital, for long-term societal benefit. Yet, current decision-making is dominated by economic imperatives and information systems that do not consider society's dependence on natural capital and the ecosystem services it provides. New international standards for natural capital accounting (NCA) are now available to integrate environmental information into government decision-making. By revealing the effects of policies that influence natural capital, NCA supports identification, implementation and monitoring of Green Recovery pathways, including where environment and economy are most positively interlinked.


Asunto(s)
COVID-19 , Ecosistema , Humanos , Conservación de los Recursos Naturales , COVID-19/epidemiología , Pandemias
20.
J Hazard Mater ; 442: 130128, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36303338

RESUMEN

Glyphosate (GLY) and flazasulfuron (FLA) are two non-selective herbicides commonly applied together. However, research focused on their single and combined ecotoxicological impacts towards non-target organisms is still inconclusive. Therefore, this study aimed to test their single effects on soil's habitat and retention functions, and to unravel their combined impacts to earthworms and terrestrial plants. For this, ecotoxicological assays were performed with plants (Medicago sativa), oligochaetes (Eisenia fetida) and collembola (Folsomia candida). Soil elutriates were also prepared and tested in macrophytes (Lemna minor) and microalgae (Raphidocelis subcapitata). FLA (82-413 µg kg-1) reduced earthworms' and collembola's reproduction and severely impaired M. sativa growth, being much more toxic than GLY (up to 30 mg kg-1). In fact, the latter only affected plant growth (≥ 9 mg kg-1) and earthworms (≥ 13 mg kg-1), especially at high concentrations, with no effects on collembola. Moreover, only elutriates from FLA-contaminated soils significantly impacted L. minor and R. sucapitata. The experiments revealed that the co-exposure to GLY and FLA enhanced the toxic effects of contaminated soils not only on plants but also on earthworms'. However, such increase in toxicity was dependent on GLY residual concentrations in soils. Overall, this work underpins that herbicides risk assessment should consider herbicides co-exposures, since the evaluation of single exposures is not representative of current phytosanitary practices and of the potential effects under field conditions, where residues of different compounds may persist in soils.


Asunto(s)
Artrópodos , Herbicidas , Oligoquetos , Contaminantes del Suelo , Animales , Suelo/química , Contaminantes del Suelo/análisis , Ecosistema , Herbicidas/toxicidad , Plantas
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