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1.
Nature ; 577(7790): 318, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31937963
2.
Oecologia ; 192(2): 439-448, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31938884

RESUMO

Population projections coupled with downscaled climate projections are a powerful tool that allows predicting future population dynamics of vulnerable plants in the face of a changing climate. Traditional approaches used to predict the vulnerability of plants to climate change (e.g. species distribution models) fail to mechanistically describe the basis of a population's dynamics and thus cannot be expected to correctly predict its temporal trends. In this study, we used a 23-year demographic dataset of the acuña cactus, an endangered species, to predict its population dynamics to the end of the century. We used integral projection models to describe its vital rates and population dynamics in relation to plant volume and key climatic variables. We used the resulting climate-driven IPM along with climatic projections to predict the population growth rates from 1991 to 2099. We found the average population growth rate of this population between 1991 and 2013 to be 0.70 (95% CI 0.61-0.79). This result confirms that the population of acuña cactus has been declining and that this decline is due to demographic structure and climate conditions. However, the projection model also predicts that, up to 2080, the population will remain relatively stable mainly due to the survival of its existing adult individuals. Notwithstanding, the long-term viability of the populations can only be achieved through the recruitment of new individuals.


Assuntos
Cactaceae , Mudança Climática , Animais , Dinâmica Populacional , Previsões Demográficas , Crescimento Demográfico
3.
Insect Sci ; 27(2): 266-275, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30102013

RESUMO

The interaction of house dust mites (HDM) and microorganisms is the key factor in the survival of these mites in human-made environments. Spent growth medium (SPGM) provides the rest of the diet, along with dead mite bodies and microorganisms. SPGM represents a source of microorganisms for the recolonization of mite food and the mite digestive tract. An experiment was performed to observe how adding SPGM to the HDM diet affects HDM population growth, the microbiome composition and the microbial respiration in microcosms. We analyzed American house dust mite (Dermatophagoides farinae) and European house dust mite (Dermatophagoides pteronyssinus) originating from control diets and diets treated with an extract of SPGM from 1- and 3-month-old mite cultures. The microbiome was described using 16S and 18S barcode sequencing. The composition of the bacterial and fungal microbiomes differed between the HDM species, but the SPGM treatment influenced only the bacterial profile of D. farinae. In the D. farinae microbiome of specimens on SPGM-treated diets compared to those of the control situation, the Lactobacillus profile decreased, while the Cardinium, Staphylococcus, Acinetobacter, and Sphingomonas profiles increased. The addition of SPGM extract decreased the microbial respiration in the microcosms with and without mites in almost all cases. Adding SPGM did not influence the population growth of D. farinae, but it had a variable effect on D. pteronyssinus. The results indicated that the HDM are marginally influenced by the microorganisms in their feces.


Assuntos
Dermatophagoides pteronyssinus/microbiologia , Microbiota , Animais , Meios de Cultura , Feminino , Aptidão Genética , Masculino , Crescimento Demográfico
4.
J Insect Sci ; 19(5)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31612945

RESUMO

The green peach aphid, Myzus persicae Sulzer (Hemiptera: Aphididae), is an important agricultural pest with a wide range of host plants. To study effects of host species on the life history traits of M. persicae, aphids were individually reared on five host plants: Brassica campestris L. (Brassicales: Brassicaceae), Capsicum annuum L. (Tubiflorae: Solanaceae), Nicotiana tabacum L. (Tubiflorae: Solanaceae), Raphanus sativus L. (Brassicales: Brassicaceae), and Vicia faba L. (Rosales: Leguminosae). TWOSEX-MSchart software was used for the statistical analysis according to the age-stage, two-sex life table theory. The results showed that the shortest preadult stage and adult/total prereproductive period of M. persicae were 6.48, 0.19, and 6.67 d on V. faba, respectively. While the adult and total longevity of M. persicae on R. sativus (25.00 and 31.62 d) and N. tabacum (24.40 and 30.56 d) were significantly longer than that on the other three hosts, as was the reproductive period. The fecundity of M. persicae on R. sativus (80.83 nymphs per female), N. tabacum (71.72 nymphs per female), and V. faba (70.39 nymphs per female) was also greater than that on B. campestris and C. annuum. It was demonstrated that V. faba, R. sativus, and N. tabacum were more suitable plants for the growth of M. persicae exhibiting a shorter preadult stage, longer longevity, and greater fecundity than the remaining two species, as confirmed by the higher intrinsic rate of increase and net reproductive rate.


Assuntos
Afídeos/fisiologia , Cadeia Alimentar , Herbivoria , Traços de História de Vida , Animais , Afídeos/crescimento & desenvolvimento , Feminino , Longevidade , Magnoliopsida/fisiologia , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Crescimento Demográfico
5.
Environ Sci Pollut Res Int ; 26(32): 33076-33085, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31515766

RESUMO

The profound appreciation of urban expansion and land use change (LUC) considerably influences the ecosystem functions, services, and biodiversity along with the local and regional climate. Land use has undergone an awful transformation due to rapid urbanization and population growth, which in turn increased land surface temperature (LST) in district Peshawar, Pakistan. The current study tends to capture the influence of land use on LST and agricultural productivity by employing multi-temporal, multispectral satellite data and agricultural production data during the selected years, i.e., 1996, 2003, and 2016. The results demonstrated that barren land considerably decreased while the urban area increased over time in all three phases. Furthermore, significant LST difference was found in different land cover units; e.g., barren land and urban area have the maximum, while water bodies followed by vegetation retain minimum LST in all three phases, i.e., 1996, 2003, and 2016. Similarly, the results from agricultural production revealed that except for wheat crops, which decreased by 7.54% during 1999-2003, the production of all major food crops increased during the selected years. However, the production of sugar cane and barley experienced considerable reduction during the selected years, except for barley, which increased by 22.86% during 2003-2016. The finding of this study provides guidance, policy recommendations, and reference for future researchers. Graphical abstract .


Assuntos
Agricultura , Monitoramento Ambiental , Urbanização , Clima , Conservação dos Recursos Naturais , Ecossistema , Paquistão , Crescimento Demográfico , Temperatura Ambiente
6.
Environ Entomol ; 48(6): 1323-1330, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31553792

RESUMO

Soil chemistry and microbial diversity can impact the vigor and nutritive qualities of plants, as well as plants' ability to deploy anti-herbivore defenses. Soil qualities often vary dramatically on organic versus conventional farms, reflecting the many differences in soil management practices between these farming systems. We examined soil-mediated effects on herbivore performance by growing potato plants (Solanum tuberosum L.) in soils collected from organic or conventional commercial farm fields, and then exposing these plants to herbivory by green peach aphids (Myzus persicae Sulzer, Hemiptera: Aphididae) and/or Colorado potato beetles (Leptinotarsa decemlineata Say, Coleoptera: Chrysomelidae). Responses of the two potato pests varied dramatically. Survivorship of Colorado potato beetles was almost 3× higher on plants grown in organic than in conventional soils, but was unaffected by the presence of aphids. In contrast, aphid colony growth was twice as rapid when aphids were reared alone rather than with Colorado potato beetles, but was unaffected by soil type. We saw no obvious differences in soil nutrients when comparing organic and conventional soils. However, we saw a higher diversity of bacteria in organic soils, and potato plants grown in this soil had a lower carbon concentration in foliar tissue. In summary, the herbivore species differed in their susceptibility to soil- versus competitor-mediated effects, and these differences may be driven by microbe-mediated changes in host plant quality. Our results suggest that soil-mediated effects on pest growth can depend on herbivore species and community composition, and that soil management strategies that promote plant health may also increase host quality for pests.


Assuntos
Afídeos , Besouros , Solanum tuberosum , Animais , Colorado , Crescimento Demográfico , Solo
7.
Glob Chang Biol ; 25(11): 3680-3693, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31475774

RESUMO

All long-distance migrants must cope with changing environments, but species differ greatly in how they do so. In some species, individuals might be able to adjust by learning from individual experiences and by copying others. This could greatly speed up the process of adjustment, but evidence from the wild is scarce. Here, we investigated the processes by which a rapidly growing population of barnacle geese (Branta leucopsis) responded to strong environmental changes on spring-staging areas in Norway. One area, Helgeland, has been the traditional site. Since the mid-1990s, an increasing number of geese stage in another area 250 km further north, Vesterålen. We collected data on goose numbers and weather conditions from 1975 to 2017 to explore the extent to which the increase in population size and a warmer climate contributed to this change in staging area use. During the study period, the estimated onset of grass growth advanced on average by 0.54 days/year in each of the two areas. The total production of digestible biomass for barnacle geese during the staging period increased in Vesterålen but remained stable in Helgeland. The goose population has doubled in size during the past 25 years, with most of the growth being accommodated in Vesterålen. The observations suggest that this dramatic increase would not have happened without higher temperatures in Vesterålen. Records of individually marked geese indicate that from the initial years of colonization onwards, especially young geese tended to switch to Vesterålen, thereby predominating in the flocks at Vesterålen. Older birds had a lower probability of switching to Vesterålen, but over the years, the probability increased for all ages. Our findings suggest that barnacle geese integrate socially learned behaviour with adjustments to individual experiences, allowing the population to respond rapidly and accurately to global change.


Assuntos
Gansos , Thoracica , Migração Animal , Animais , Mudança Climática , Noruega , Crescimento Demográfico , Estações do Ano
8.
Environ Monit Assess ; 191(9): 600, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31468148

RESUMO

Varanasi district is comprised of eight administrative blocks. Owing to economic development, it has shown an increase in urban activities. Analysis of remotely sensed data for a period of two decades reveals that the built-up area increased by about 345% while vegetation decreased by 86% during 1993-2013. Contrary to other observations, land use changes, due to urban growth, increased not only the built area but also the agriculture class. Agricultural area increased by 39% in the two decades. Population density increased from 1217 to 1806 person/km2 and household density grew from 152 to 273 households/km2 during 1991-2011. Land absorption coefficient (LAC) and land consumption ratio (LCR) were calculated as demographic indices of land use land cover change (LULC). Vegetation delineation shows that sparse vegetation increased from 40.2 to 90.1 km2 while dense vegetation decreased from 28.4 to 1.7 km2 in 1993-2013. There was a distinct shift from agriculture, as a primary economic activity, towards non-agricultural pursuits. In order to frame better strategies for sustainable development and food security, this phenomenon of increasing urbanization around cities needs to be studied. This micro scale study can be helpful in formulating policy for urban areas in developing countries like India which heavily depend on agriculture to sustain their population and economy.


Assuntos
Agricultura/tendências , Monitoramento Ambiental , Urbanização/tendências , Cidades , Planejamento de Cidades , Conservação dos Recursos Naturais , Abastecimento de Alimentos , Índia , Plantas , Crescimento Demográfico
12.
Ecology ; 100(10): e02789, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31298734

RESUMO

Population responses to environmental change depend on both the ecological interactions between species and the evolutionary responses of all species. In this study, we explore how evolution in prey, predators, or both species affect the responses of predator populations to a sustained increase in mortality. We use an eco-evolutionary predator-prey model to explore how evolution alters the predator extinction threshold (defined as the minimum mortality rate that prevents population growth at low predator densities) and predator hydra effects (increased predator abundance in response to increased mortality). Our analysis identifies how evolutionary responses of prey and predators individually affect the predator extinction threshold and hydra effects, and how those effects are altered by interactions between the evolutionary responses. Based on our theoretical results, we predict that it is common in natural systems for evolutionary responses in one or both species to allow predators to persist at higher mortality rates than would be possible in the absence of evolution (i.e., evolution increases the predator mortality extinction threshold). We also predict that evolution-driven hydra effects occur in a minority of natural systems, but are not rare. We revisited published eco-evolutionary models and found that evolution causes hydra effects and increases the predator extinction threshold in many studies, but those effects have been overlooked. We discuss the implications of these results for species conservation, predicting population responses to environmental change, and the possibility of evolutionary rescue.


Assuntos
Hydra , Animais , Evolução Biológica , Dinâmica Populacional , Crescimento Demográfico , Comportamento Predatório
13.
Oecologia ; 190(4): 821-833, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31309278

RESUMO

Life-history information sets the foundation for our understanding of ecology and conservation requirements. For many species, this information is lacking even for basic demographic rates such as survival and movement. When survival and movement estimates are available, they are often derived from mixed demographic groups and do not consider differences among life stages or sexes, which is critical, because life stages and sexes often contribute differentially to population dynamics. We used hierarchical models informed with spatial capture-mark-recapture data of Ascaphus montanus (Rocky Mountain tailed frog) in five streams and A. truei (coastal tailed frog) in one stream to estimate variation in survival and movement by sex and age, represented by size. By incorporating survival and movement into a single model, we were able to estimate both parameters with limited bias. Annual survival was similar between sexes of A. montanus [females = 0.885 (95% CI 0.614-1), males = 0.901 (0.657-1)], but was slightly higher for female A. truei [0.836 (0.560-0.993)] than for males [0.664 (0.354-0.962)]. Survival of A. montanus peaked at mid-age, suggesting that lower survival of young and actuarial senescence may influence population demographics. Our models suggest that younger A. montanus moved farther than older individuals, and that females moved farther than males in both species. Our results provide uncommon insight into age- and sex-specific rates of survival and movement that are crucial elements of life-history strategies and are important for modeling population growth and prescribing conservation actions.


Assuntos
Traços de História de Vida , Crescimento Demográfico , Anfíbios , Animais , Demografia , Feminino , Masculino , Dinâmica Populacional
14.
Environ Monit Assess ; 191(8): 480, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31270626

RESUMO

Land use/cover (LCLU) is considered as one of the most serious environmental challenges that threatens developed and less developed countries. LCLU changes' monitoring using the integration of remote sensing (RS) and geographical information systems (GIS) and their predicting using an artificial neural network (ANN) in the western part of the Tarim River Basin (Aksu), north-western Xinjiang-China, from 1990 to 2030 have been investigated first time through satellite imageries available. The imageries of 1990, 2000, 2005, 2010, and 2015 were downloaded from GLCF and USGS websites. After digital image processing, the object-oriented image classification approach was applied. The ANN method with MOLUSCE Plugin was used to simulate the LCLU changes in 2020, 2025, and 2030. GIS has also been used to calculate the distance from the road and water and etc. The simulation results of 2010 and 2015 were validated using classification data with Kappa coefficient. The results showed high accuracy of the classification and prediction as the validation of simulated 2010 and 2015 maps to the referenced maps have high accuracy of Kappa 84 and 88%, respectively. The results revealed that the land cover classes forest-, grass-, wet-, and barren land have been decreased from 50.01, 13.06, 8.24, and 1.06% in 1990 to 32.03, 3.06, 6.26, and 0.97% in 2015, respectively, while the land use classes, crop or farm land, and urban land have been increased almost double from 25.5 and 2.13% in 1990 to 53.71 and 3.86% from the total area in 2015, respectively. For the prediction, forest- and wetlands will loss more than half of their areas by 2030, the grass land will be cleared completely to be only 1.3% from the total study area, while the urban land will be increased to be 4.4% or the double of 1990. These results are attributed to population growth and expanding of agriculture land on the grass land, but the effect of climate was weak as the rainfall increased during the study period. Causes and effects of the LCLU changes were briefly discussed. The output of the study serves as useful tools for policy and decision makers combatting natural resources misused in arid lands.


Assuntos
Monitoramento Ambiental/métodos , Agricultura , China , Clima , Conservação dos Recursos Naturais , Florestas , Sistemas de Informação Geográfica , Crescimento Demográfico , Rios , Imagens de Satélites , Áreas Alagadas
15.
Environ Monit Assess ; 191(8): 486, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31289942

RESUMO

Over the past few decades, natural reserves have been affected by both climate change and human activities, and their land cover has changed dramatically, especially in mountain reserves, which are more sensitive to climate change and human activities. This paper used long-term Landsat and MODIS NDVI remote sensing data to monitor the changes of land cover and vegetation conditions in the Qilian Mountain National Nature Reserve (QMNNR) in China from 1975 to 2015, and analysed the impacts of climate change and human activities in combination with meteorological and socioeconomic data. The results show that the land cover structure of the QMNNR has remained stable over the past 40 years, but the total area of natural vegetation has decreased by 49.55 km2, the artificial surface and cropland has expanded by 13.68 and 32.57 km2 in some areas, respectively, and the glacier has retreated by 33.34 km2 as a whole. The warming and humidification trend of the climate is the leading factor for glacial retreat and the improvement of the overall vegetation condition, while population growth and economic benefits lead to the expansion of cropland and artificial surfaces in some areas, thus causing the reduction of 18.80 and 28.30 km2 in shrubland and grassland. This study proves that the system of protected areas plays a key role in maintaining the stability of the ecosystem structure and that reducing the population density around the protected areas and changing the mode of economic development can effectively reduce the intensity of human interference. Under the background of climate warming, the change of the ecosystem function in mountain protected areas is full of uncertainty, so management and protection strategies need to be studied in depth.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais/métodos , Ecossistema , China , Monitoramento Ambiental/métodos , Humanos , Camada de Gelo , Densidade Demográfica , Crescimento Demográfico
16.
Enferm. foco (Brasília) ; 10(3): 58-63, jul. 2019. tab
Artigo em Português | LILACS, BDENF - Enfermagem | ID: biblio-1049790

RESUMO

Objetivo: avaliar a qualidade de vida de idosos participantes de um grupo de convivência; verificar o perfil sociodemográfico. Metodologia: Trata-se de um estudo com abordagem quantitativa do tipo descritiva, onde foi aplicado um questionário sociodemográfico e o instrumento Whoqol-Bref para avaliar a qualidade de vida de 103 idosos de um centro de convivência de Belém do Pará. Resultados: a maioria são idosas (90,29%), possuem faixa etária entre 70-75 anos (31,07%), escolaridade 8 anos ou mais (75,73%), aposentado (a) ou pensionista (89%). Em relação ao instrumento Whoqol-bref os idosos apresentaram maior escore no domínio de percepção da qualidade de vida (µ = 4.15 ± 0.61) e relações sociais (µ = 4.05 ± 0.46). Conclusão: Os idosos participantes do grupo de convivência possuem boa qualidade de vida. (AU)


Objective: to evaluate the quality of life of elderly participants of a coexistence group; verify the sociodemographic profile. Methodology: This is a descriptive quantitative study, where a sociodemographic questionnaire and the Whoqol-Bref instrument were used to evaluate the quality of life of 103 elderly people from a community center in Belém do Pará. Results: most of them are elderly with age range between 70-75 years, schooling 8 years or more, pen-sioned/retired. In relation to the Whoqol-bref instrument, the elderly presented a higher score in the domain of perception of quality of life and social relations, followed respectively by physical, psychological, health satisfaction and ambient environment. Conclusion: Most retired elderly women demonstrated to have a good quality of life, highlighted for the domain of this perception and social relations. (AU)


Objetivo: evaluar la calidad de vida de los ancianos participantes de un grupo de convivencia; verificar el perfil sociodemográfico. Metodología: Se trata de un estudio con abordaje cuanti-tativo del tipo descriptivo, donde se aplicó un cuestionario sociodemográfico y el instrumento Whoqol-Bref para evaluar la calidad de vida de 103 ancianos de un centro de convivencia de Belém do Pará. Resultados: la mayoría son mujeres, tienen rango de edad entre 70-75 años, escolaridad 8 años o más, pensionista/jubilado. En cuanto al instrumento Whoqol-bref, los ancianos presentaron mayor puntuación en el dominio de percepción de la calidad de vida y relaciones sociales seguido respectivamente por la satisfacción física, psicológica, de salud y, por último, el medio ambiente. Conclusión: La mayoría de las mujeres ancionas fueran jubi-ladas demostraron tener una buena calidad de vida, destacada por el dominio de esta percep-ción y las relaciones sociales. (AU)


Assuntos
Idoso , Qualidade de Vida , Enfermagem , Crescimento Demográfico , Envelhecimento Saudável
17.
Nat Biotechnol ; 37(7): 744-754, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31209375

RESUMO

Crop improvements can help us to meet the challenge of feeding a population of 10 billion, but can we breed better varieties fast enough? Technologies such as genotyping, marker-assisted selection, high-throughput phenotyping, genome editing, genomic selection and de novo domestication could be galvanized by using speed breeding to enable plant breeders to keep pace with a changing environment and ever-increasing human population.


Assuntos
Produtos Agrícolas/genética , Abastecimento de Alimentos , Engenharia Genética/métodos , Humanos , Melhoramento Vegetal , Crescimento Demográfico
20.
Parasit Vectors ; 12(1): 213, 2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31064400

RESUMO

BACKGROUND: The poultry red mite (PRM), Dermanyssus gallinae, is one of the most economically deleterious ectoparasites affecting egg-laying hens worldwide. It may be possible to control D. gallinae populations by manipulating lighting regimes within poultry units. However, no studies have clearly shown the effects of darkness on the population growth rate of D. gallinae. METHODS: The effect of darkness on the population growth rate of D. gallinae was investigated, together with the first description of the molecular identity of the mite from China. Mite variables under two lighting regimens (1:23 h L:D and 12:12 h L:D) were compared, including number of mites and eggs, survival and feeding rates, engorgement, oviposition, hatchability and the life-cycle of D. gallinae. RESULTS: The results showed that the number of mites (13,763 ± 956) and eggs (5424 ± 317) in the rearing system with prolonged darkness of 1:23 h L:D at 4th week were 2.4- and 3.6-fold higher than those under a conventional lighting regimen of 12:12 h L:D, respectively. The feeding rates of mites under prolonged darkness ranged from 36.7 ± 1.1% to 52.0 ± 7.0%, which were significantly higher than those under conventional lighting regimen (ranging from 22.6 ± 1.9% to 37.3 ± 1.6%). The mean weight of engorged females (0.26 ± 0.01 mg) and the mean number of eggs per female (on average 5.87 ± 0.36) under prolonged darkness were significantly higher than those under conventional lighting regimen (0.22 ± 0.01 mg and 3.62 ± 0.31, respectively). However, the survival rate ranging from 98.07 ± 0.10% to 98.93 ± 0.19%, hatchability of 97.93 ± 0.01% and the life-cycle of D. gallinae (9 days) was not affected by the lighting period. CONCLUSIONS: Our findings demonstrated that prolonged darkness significantly promoted the proliferation levels of D. gallinae, resulting in increased number of mites and eggs in the rearing system. The promoted population growth of D. gallinae was found to be related to the increased feeding rate, engorgement level and oviposition level of mites under prolonged darkness. The egg hatchability, the survival rates and the duration of life-cycle of D. gallinae were not affected by the light regimes.


Assuntos
Escuridão , Ácaros/efeitos da radiação , Animais , Galinhas , DNA Intergênico , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Comportamento Alimentar/efeitos da radiação , Feminino , Estágios do Ciclo de Vida , Luz , Infestações por Ácaros/veterinária , Ácaros/genética , Ácaros/crescimento & desenvolvimento , Oviposição/efeitos da radiação , Fotoperíodo , Crescimento Demográfico , Doenças das Aves Domésticas/parasitologia , Reprodução/efeitos da radiação , Fatores de Tempo
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