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1.
Recurso de Internet en Inglés, Español, Francés, Portugués | LIS - Localizador de Información en Salud | ID: lis-49652

RESUMEN

Um novo relatório da Organização Pan-Americana da Saúde (OPAS) revela que, embora a expectativa de vida tenha aumentado nas Américas, também aumentou o número de pessoas que vivem com Doenças Crônicas Não Transmissíveis (DCNT).


Asunto(s)
Enfermedades no Transmisibles/mortalidad , Informe de Investigación , Américas/epidemiología , Dinámica Poblacional/estadística & datos numéricos
2.
J R Soc Interface ; 21(216): 20240278, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38955228

RESUMEN

The wildlife and livestock interface is vital for wildlife conservation and habitat management. Infectious diseases maintained by domestic species may impact threatened species such as Asian bovids, as they share natural resources and habitats. To predict the population impact of infectious diseases with different traits, we used stochastic mathematical models to simulate the population dynamics over 100 years for 100 times in a model gaur (Bos gaurus) population with and without disease. We simulated repeated introductions from a reservoir, such as domestic cattle. We selected six bovine infectious diseases; anthrax, bovine tuberculosis, haemorrhagic septicaemia, lumpy skin disease, foot and mouth disease and brucellosis, all of which have caused outbreaks in wildlife populations. From a starting population of 300, the disease-free population increased by an average of 228% over 100 years. Brucellosis with frequency-dependent transmission showed the highest average population declines (-97%), with population extinction occurring 16% of the time. Foot and mouth disease with frequency-dependent transmission showed the lowest impact, with an average population increase of 200%. Overall, acute infections with very high or low fatality had the lowest impact, whereas chronic infections produced the greatest population decline. These results may help disease management and surveillance strategies support wildlife conservation.


Asunto(s)
Modelos Biológicos , Dinámica Poblacional , Animales , Tailandia/epidemiología , Bovinos , Animales Salvajes , Enfermedades Transmisibles/epidemiología , Enfermedades Transmisibles/veterinaria , Enfermedades Transmisibles/transmisión , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/microbiología , Rumiantes/microbiología
4.
J R Soc Interface ; 21(216): 20240217, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38981516

RESUMEN

Mathematical models in ecology and epidemiology must be consistent with observed data in order to generate reliable knowledge and evidence-based policy. Metapopulation systems, which consist of a network of connected sub-populations, pose technical challenges in statistical inference owing to nonlinear, stochastic interactions. Numerical difficulties encountered in conducting inference can obstruct the core scientific questions concerning the link between the mathematical models and the data. Recently, an algorithm has been proposed that enables computationally tractable likelihood-based inference for high-dimensional partially observed stochastic dynamic models of metapopulation systems. We use this algorithm to build a statistically principled data analysis workflow for metapopulation systems. Via a case study of COVID-19, we show how this workflow addresses the limitations of previous approaches. The COVID-19 pandemic provides a situation where mathematical models and their policy implications are widely visible, and we revisit an influential metapopulation model used to inform basic epidemiological understanding early in the pandemic. Our methods support self-critical data analysis, enabling us to identify and address model weaknesses, leading to a new model with substantially improved statistical fit and parameter identifiability. Our results suggest that the lockdown initiated on 23 January 2020 in China was more effective than previously thought.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , Humanos , Algoritmos , Modelos Biológicos , Dinámica Poblacional , Pandemias
5.
Proc Biol Sci ; 291(2026): 20240980, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38981521

RESUMEN

Ecological and evolutionary predictions are being increasingly employed to inform decision-makers confronted with intensifying pressures on biodiversity. For these efforts to effectively guide conservation actions, knowing the limit of predictability is pivotal. In this study, we provide realistic expectations for the enterprise of predicting changes in ecological and evolutionary observations through time. We begin with an intuitive explanation of predictability (the extent to which predictions are possible) employing an easy-to-use metric, predictive power PP(t). To illustrate the challenge of forecasting, we then show that among insects, birds, fishes and mammals, (i) 50% of the populations are predictable at most 1 year in advance and (ii) the median 1-year-ahead predictive power corresponds to a prediction R 2 of only 20%. Predictability is not an immutable property of ecological systems. For example, different harvesting strategies can impact the predictability of exploited populations to varying degrees. Moreover, incorporating explanatory variables, accounting for time trends and considering multivariate time series can enhance predictability. To effectively address the challenge of biodiversity loss, researchers and practitioners must be aware of the information within the available data that can be used for prediction and explore efficient ways to leverage this knowledge for environmental stewardship.


Asunto(s)
Biodiversidad , Evolución Biológica , Conservación de los Recursos Naturales , Animales , Aves/fisiología , Peces/fisiología , Insectos/fisiología , Predicción , Mamíferos , Dinámica Poblacional , Modelos Biológicos
6.
Glob Chang Biol ; 30(7): e17414, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39044553

RESUMEN

As climatic variation re-shapes global biodiversity, understanding eco-evolutionary feedbacks during species range shifts is of increasing importance. Theory on range expansions distinguishes between two different forms: "pulled" and "pushed" waves. Pulled waves occur when the source of the expansion comes from low-density peripheral populations, while pushed waves occur when recruitment to the expanding edge is supplied by high-density populations closer to the species' core. How extreme events shape pushed/pulled wave expansion events, as well as trailing-edge declines/contractions, remains largely unexplored. We examined eco-evolutionary responses of a marine invertebrate (the owl limpet, Lottia gigantea) that increased in abundance during the 2014-2016 marine heatwaves near the poleward edge of its geographic range in the northeastern Pacific. We used whole-genome sequencing from 19 populations across >11 degrees of latitude to characterize genomic variation, gene flow, and demographic histories across the species' range. We estimated present-day dispersal potential and past climatic stability to identify how contemporary and historical seascape features shape genomic characteristics. Consistent with expectations of a pushed wave, we found little genomic differentiation between core and leading-edge populations, and higher genomic diversity at range edges. A large and well-mixed population in the northern edge of the species' range is likely a result of ocean current anomalies increasing larval settlement and high-dispersal potential across biogeographic boundaries. Trailing-edge populations have higher differentiation from core populations, possibly driven by local selection and limited gene flow, as well as high genomic diversity likely as a result of climatic stability during the Last Glacial Maximum. Our findings suggest that extreme events can drive poleward range expansions that carry the adaptive potential of core populations, while also cautioning that trailing-edge extirpations may threaten unique evolutionary variation. This work highlights the importance of understanding how both trailing and leading edges respond to global change and extreme events.


Asunto(s)
Evolución Biológica , Cambio Climático , Animales , Flujo Génico , Dinámica Poblacional , Distribución Animal , Variación Genética
7.
Biol Lett ; 20(7): 20240158, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39044630

RESUMEN

Drift and gene flow affect genetic diversity. Given that the strength of genetic drift increases as population size decreases, management activities have focused on increasing population size through preserving habitats to preserve genetic diversity. Few studies have empirically evaluated the impacts of drift and gene flow on genetic diversity. Kryptolebias marmoratus, henceforth 'rivulus', is a small killifish restricted to fragmented New World mangrove forests with gene flow primarily associated with ocean currents. Rivulus form distinct populations across patches, making them a well-suited system to test the extent to which habitat area, fragmentation and connectivity are associated with genetic diversity. Using over 1000 individuals genotyped at 32 microsatellite loci, high-resolution landcover data and oceanographic simulations with graph theory, we demonstrate that centrality (connectivity) to the metapopulation is more strongly associated with genetic diversity than habitat area or fragmentation. By comparing models with and without centrality standardized by the source population's genetic diversity, our results suggest that metapopulation centrality is critical to genetic diversity regardless of the diversity of adjacent populations. While we find evidence that habitat area and fragmentation are related to genetic diversity, centrality is always a significant predictor with a larger effect than any measure of habitat configuration.


Asunto(s)
Ecosistema , Fundulidae , Variación Genética , Animales , Fundulidae/genética , Flujo Génico , Repeticiones de Microsatélite , Densidad de Población , Dinámica Poblacional
8.
J Math Biol ; 89(2): 22, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951257

RESUMEN

Group defense in prey and hunting cooperation in predators are two important ecological phenomena and can occur concurrently. In this article, we consider cooperative hunting in generalist predators and group defense in prey under a mathematical framework to comprehend the enormous diversity the model could capture. To do so, we consider a modified Holling-Tanner model where we implement Holling type IV functional response to characterize grazing pattern of predators where prey species exhibit group defense. Additionally, we allow a modification in the attack rate of predators to quantify the hunting cooperation among them. The model admits three boundary equilibria and up to three coexistence equilibrium points. The geometry of the nontrivial prey and predator nullclines and thus the number of coexistence equilibria primarily depends on a specific threshold of the availability of alternative food for predators. We use linear stability analysis to determine the types of hyperbolic equilibrium points and characterize the non-hyperbolic equilibrium points through normal form and center manifold theory. Change in the model parameters leading to the occurrences of a series of local bifurcations from non-hyperbolic equilibrium points, namely, transcritical, saddle-node, Hopf, cusp and Bogdanov-Takens bifurcation; there are also occurrences of global bifurcations such as homoclinic bifurcation and saddle-node bifurcation of limit cycles. We observe two interesting closed 'bubble' form induced by global bifurcations due to change in the strength of hunting cooperation and the availability of alternative food for predators. A three dimensional bifurcation diagram, concerning the original system parameters, captures how the alternation in model formulation induces gradual changes in the bifurcation scenarios. Our model highlights the stabilizing effects of group or gregarious behaviour in both prey and predator, hence supporting the predator-herbivore regulation hypothesis. Additionally, our model highlights the occurrence of "saltatory equilibria" in ecological systems and capture the dynamics observed for lion-herbivore interactions.


Asunto(s)
Ecosistema , Cadena Alimentaria , Conceptos Matemáticos , Modelos Biológicos , Dinámica Poblacional , Conducta Predatoria , Animales , Dinámica Poblacional/estadística & datos numéricos , Conducta Cooperativa , Simulación por Computador , Herbivoria , Modelos Lineales
9.
J Math Biol ; 89(2): 24, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38955850

RESUMEN

The assembly and persistence of ecological communities can be understood as the result of the interaction and migration of species. Here we study a single community subject to migration from a species pool in which inter-specific interactions are organised according to a bipartite network. Considering the dynamics of species abundances to be governed by generalised Lotka-Volterra equations, we extend work on unipartite networks to we derive exact results for the phase diagram of this model. Focusing on antagonistic interactions, we describe factors that influence the persistence of the two guilds, locate transitions to multiple-attractor and unbounded phases, as well as identifying a region of parameter space in which consumers are essentially absent in the local community.


Asunto(s)
Ecosistema , Conceptos Matemáticos , Modelos Biológicos , Dinámica Poblacional , Dinámica Poblacional/estadística & datos numéricos , Animales , Cadena Alimentaria
10.
BMC Ecol Evol ; 24(1): 93, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969976

RESUMEN

The Persian fallow deer or Mesopotamian fallow Deer (Dama mesopotamica, Brook 1875), a species of significant ecological importance, had faced the threat of extinction in Iran. One conservation strategy involved the translocation of Persian deer to enclosed areas across Iran, where they were afforded protection from external threats and provided with essential care by human caretakers. While human caretakers diligently attend to their needs and mitigate external threats, climate variables may now become critical factors affecting population dynamics in enclosed areas. This study aims to assess the similarity in climate niches between the original area (Dez and Karkheh) of the Persian deer species and 11 newly enclosed areas. To achieve this, we employed climate data and ecological niche modeling (ENM) techniques to assess the variations in climate among 12 areas. We utilized the environmental equivalency test to determine whether the environmental spaces of area pairs exhibit significant differences and whether these spaces are interchangeable. Extrapolation analyses were also constructed in the next steps to explore climatic conditions in original fallow deer habitats that are non-analogous to those in other parts of Iran. Our results reveal significant disparities in climate conditions between the original and all translocated areas. Based on observations of population growth in specific enclosed areas where translocated deer populations have thrived, we hypothesize that the species may demonstrate a non-equilibrium distribution in Iran. Consequently, these new areas could potentially be regarded as part of the species' potential climate niche. Extrapolation analysis showed that for a significant portion of Iran, extrapolation predictions are highly uncertain and potentially unreliable for the translocation of Persian fallow deer. However, the primary objective of translocation efforts remains the establishment of self-sustaining populations of Persian deer capable of thriving in natural areas beyond enclosed areas, thus ensuring their long-term survival and contributing to preservation efforts. Evaluating the success of newly translocated species requires additional time, with varying levels of success observed. In cases where the growth rate of the species in certain enclosed areas falls below expectations, it is prudent to consider climate variables that may contribute to population declines. Furthermore, for future translocations, we recommend selecting areas with climate similarities to regions where the species has demonstrated growth rates.


Asunto(s)
Clima , Ciervos , Ecosistema , Animales , Irán , Ciervos/fisiología , Conservación de los Recursos Naturales , Dinámica Poblacional
11.
Bull Math Biol ; 86(8): 102, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976154

RESUMEN

This study presents a comprehensive analysis of a two-patch, two-life stage SI model without recovery from infection, focusing on the dynamics of disease spread and host population viability in natural populations. The model, inspired by real-world ecological crises like the decline of amphibian populations due to chytridiomycosis and sea star populations due to Sea Star Wasting Disease, aims to understand the conditions under which a sink host population can present ecological rescue from a healthier, source population. Mathematical and numerical analyses reveal the critical roles of the basic reproductive numbers of the source and sink populations, the maturation rate, and the dispersal rate of juveniles in determining population outcomes. The study identifies basic reproduction numbers R 0 for each of the patches, and conditions for the basic reproduction numbers to produce a receiving patch under which its population. These findings provide insights into managing natural populations affected by disease, with implications for conservation strategies, such as the importance of maintaining reproductively viable refuge populations and considering the effects of dispersal and maturation rates on population recovery. The research underscores the complexity of host-pathogen dynamics in spatially structured environments and highlights the need for multi-faceted approaches to biodiversity conservation in the face of emerging diseases.


Asunto(s)
Anfibios , Número Básico de Reproducción , Epidemias , Interacciones Huésped-Patógeno , Conceptos Matemáticos , Modelos Biológicos , Dinámica Poblacional , Animales , Número Básico de Reproducción/estadística & datos numéricos , Epidemias/estadística & datos numéricos , Anfibios/microbiología , Anfibios/crecimiento & desarrollo , Dinámica Poblacional/estadística & datos numéricos , Estrellas de Mar/crecimiento & desarrollo , Estrellas de Mar/microbiología , Estadios del Ciclo de Vida , Quitridiomicetos/fisiología , Quitridiomicetos/patogenicidad , Modelos Epidemiológicos , Simulación por Computador
12.
Glob Chang Biol ; 30(7): e17413, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38982678

RESUMEN

Tasmanian eucalypt forests are among the most carbon-dense in the world, but projected climate change could destabilize this critical carbon sink. While the impact of abiotic factors on forest ecosystem carbon dynamics have received considerable attention, biotic factors such as the input of animal scat are less understood. Tasmanian devils (Sarcophilus harrisii)-an osteophageous scavenger that can ingest and solubilize nutrients locked in bone material-may subsidize plant and microbial productivity by concentrating bioavailable nutrients (e.g., nitrogen and phosphorus) in scat latrines. However, dramatic declines in devil population densities, driven by the spread of a transmissible cancer, may have underappreciated consequences for soil organic carbon (SOC) storage and forest productivity by altering nutrient cycling. Here, we fuse experimental data and modeling to quantify and predict future changes to forest productivity and SOC under various climate and scat-quality futures. We find that devil scat significantly increases concentrations of nitrogen, ammonium, phosphorus, and phosphate in the soil and shifts soil microbial communities toward those dominated by r-selected (e.g., fast-growing) phyla. Further, under expected increases in temperature and changes in precipitation, devil scat inputs are projected to increase above- and below-ground net primary productivity and microbial biomass carbon through 2100. In contrast, when devil scat is replaced by lower-quality scat (e.g., from non-osteophageous scavengers and herbivores), forest carbon pools are likely to increase more slowly, or in some cases, decline. Together, our results suggest often overlooked biotic factors will interact with climate change to drive current and future carbon pool dynamics in Tasmanian forests.


Asunto(s)
Cambio Climático , Bosques , Marsupiales , Suelo , Animales , Carbono/metabolismo , Carbono/análisis , Marsupiales/fisiología , Nitrógeno/metabolismo , Nitrógeno/análisis , Fósforo/análisis , Fósforo/metabolismo , Dinámica Poblacional , Suelo/química , Microbiología del Suelo , Tasmania
13.
Sci Rep ; 14(1): 16221, 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39003385

RESUMEN

In East Africa, community-based conservation models (CBCMs) have been established to support the conservation of wildlife in fragmented landscapes like the Tarangire Ecosystem, Tanzania. To assess how different management approaches maintained large herbivore populations, we conducted line distance surveys and estimated seasonal densities of elephant, giraffe, zebra, and wildebeest in six management units, including three CBCMs, two national parks (positive controls), and one area with little conservation interventions (negative control). Using a Monte-Carlo approach to propagate uncertainties from the density estimates and trend analysis, we analyzed the resulting time series (2011-2019). Densities of the target species were consistently low in the site with little conservation interventions. In contrast, densities of zebra and wildebeest in CBCMs were similar to national parks, providing evidence that CBCMs contributed to the stabilization of these migratory populations in the central part of the ecosystem. CBCMs also supported giraffe and elephant densities similar to those found in national parks. In contrast, the functional connectivity of Lake Manyara National Park has not been augmented by CBCMs. Our analysis suggests that CBCMs can effectively conserve large herbivores, and that maintaining connectivity through CBCMs should be prioritized.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Herbivoria , Animales , Conservación de los Recursos Naturales/métodos , Tanzanía , Elefantes/fisiología , Dinámica Poblacional , Densidad de Población , Jirafas/fisiología , Equidae/fisiología
14.
J Parasitol ; 110(4): 300-310, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39034041

RESUMEN

Enteric parasites can have wide-ranging effects throughout an ecosystem, often driving coevolutionary and ecological processes. Parasites have long been overlooked in conservation efforts because of the negative impact inflicted on their hosts; however, parasites make up a significant component of Earth's biodiversity and host conservation efforts need to be parasite inclusive. The Vancouver Island marmot (VIM), Marmota vancouverensis, is an endangered alpine rodent endemic to Vancouver Island, British Columbia, Canada. Captive-bred VIMs are released to augment the wild population, but their susceptibility to parasites is unknown. The objectives of this study were to describe the diversity, prevalence, severity, and temporal variation of VIM enteric parasites. Noninvasive fecal samples were collected from wild and captive marmots and analyzed using a modified McMaster fecal egg floatation technique to indicate parasite prevalence and relative mean abundance. We identified oocysts and ova from 3 parasite taxa including a protozoan coccidium not previously described in the VIM (prevalence 68%), an ascarid nematode Baylisascaris laevis (prevalence 82%), and an anoplocephalid cestode Diandrya vancouverensis (prevalence 8%). Depending on the species, comparisons revealed variation in parasite infection by sex, by colony, and between wild and captive VIMs, but not among age classes or by female reproductive status. Finally, captive VIMs displayed significant monthly variation in parasite prevalence and mean egg abundance, suggesting a seasonal influence on parasite egg shedding. This information is critically important for future research investigating the influences of these trends on the health, ecology, and conservation of VIMs and their parasites.


Asunto(s)
Especies en Peligro de Extinción , Heces , Parasitosis Intestinales , Marmota , Dinámica Poblacional , Animales , Marmota/parasitología , Colombia Británica/epidemiología , Heces/parasitología , Femenino , Masculino , Prevalencia , Parasitosis Intestinales/veterinaria , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Enfermedades de los Roedores/parasitología , Enfermedades de los Roedores/epidemiología , Estaciones del Año , Animales Salvajes/parasitología
15.
Mol Ecol ; 33(15): e17451, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38970417

RESUMEN

Human-mediated habitat destruction has had a profound impact on increased species extinction rates and population declines worldwide. The coastal development in the United Arab Emirates (UAE) over the last two decades, serves as an example of how habitat transformation can alter the landscape of a country in just a few years. Here, we study the genomic implications of habitat transformation in the Critically Endangered Emirati Leaf-toed Gecko (Asaccus caudivolvulus), the only endemic vertebrate of the UAE. We generate a high-quality reference genome for this gecko, representing the first reference genome for the family Phyllodactylidae, and produce whole-genome resequencing data for 23 specimens from 10 different species of leaf-toed geckos. Our results show that A. caudivolvulus has consistently lower genetic diversity than any other Arabian species of Asaccus, suggesting a history of ancient population declines. However, high levels of recent inbreeding are recorded among populations in heavily developed areas, with a more than 50% increase in long runs of homozygosity within a 9-year period. Moreover, results suggest that this species does not effectively purge deleterious mutations, hence making it more vulnerable to future stochastic threats. Overall, results show that A. caudivolvulus is in urgent need of protection, and habitat preservation must be warranted to ensure the species' survival.


Asunto(s)
Ecosistema , Especies en Peligro de Extinción , Genética de Población , Endogamia , Lagartos , Animales , Lagartos/genética , Emiratos Árabes Unidos , Variación Genética , Dinámica Poblacional , Genoma/genética , Humanos , Conservación de los Recursos Naturales
16.
Bull Math Biol ; 86(8): 101, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970749

RESUMEN

We establish a general framework using a diffusion approximation to simulate forward-in-time state counts or frequencies for cladogenetic state-dependent speciation-extinction (ClaSSE) models. We apply the framework to various two- and three-region geographic-state speciation-extinction (GeoSSE) models. We show that the species range state dynamics simulated under tree-based and diffusion-based processes are comparable. We derive a method to infer rate parameters that are compatible with given observed stationary state frequencies and obtain an analytical result to compute stationary state frequencies for a given set of rate parameters. We also describe a procedure to find the time to reach the stationary frequencies of a ClaSSE model using our diffusion-based approach, which we demonstrate using a worked example for a two-region GeoSSE model. Finally, we discuss how the diffusion framework can be applied to formalize relationships between evolutionary patterns and processes under state-dependent diversification scenarios.


Asunto(s)
Simulación por Computador , Extinción Biológica , Especiación Genética , Conceptos Matemáticos , Modelos Biológicos , Filogenia , Animales , Modelos Genéticos , Evolución Biológica , Dinámica Poblacional/estadística & datos numéricos
17.
Huan Jing Ke Xue ; 45(7): 3983-3994, 2024 Jul 08.
Artículo en Chino | MEDLINE | ID: mdl-39022946

RESUMEN

In order to understand the stability of the zooplankton and phytoplankton communities in the Guizhou plateau reservoir environment, the process of reservoir water quality change affecting the stability of plankton was studied. The changes in the plankton community and water quality in three different nutrient reservoirs (Huaxi Reservoir, Goupitan Reservoir, and Hailong Reservoir) were studied from October 2020 to August 2021. The stability of the zooplankton and phytoplankton communities was studied using time-lag analysis (TLA). Variance decomposition analysis (VPA) was used to explore the response of the two communities to environmental changes. The driving factors of plankton community changes in reservoirs were also revealed. The results showed that Huaxi Reservoir and Goupitan Reservoir were mesotrophic reservoirs, and Hailong Reservoir was a eutrophic reservoir. The average comprehensive nutrition indices of the three reservoirs were 44.07, 44.68, and 50.25. A total of 51 species of zooplankton rotifers, 39 species of rotifers, three species of copepods, and nine species of cladocera were identified. Among them, the abundance of rotifers was the highest, accounting for 85.96%. A total of seven phyla and 73 species of phytoplankton were identified, including 16 species in the phylum Cyanophyta, 32 species in the phylum Chlorophyta, 16 species in the phylum Diatoma, three species in the phylum Chlorophyta, four species in the phylum Euglenophyta, and one species each in the phyla Cryptophyta and Chrysophyta. Among them, the abundance of cyanobacteria and diatoms was the highest, accounting for 66.2% and 27.35%, respectively. The median absolute deviation (MAD) of the Bray-Curtis distance of zooplankton and phytoplankton community in the three reservoirs were 0.67 and 0.65 in Huaxi Reservoir, 0.80 and 0.69 in Goupitan Reservoir, and 0.85 and 0.47 in Hailong Reservoir, respectively. The larger the value, the greater the variation in the community. The absolute value of the slope of zooplankton was greater than that of phytoplankton in the TLA results, and the absolute values of the slopes were 0.018 and 0.004, respectively. The larger the absolute value of the slope, the faster the community variability. The zooplankton community in the three reservoirs was less stable than the phytoplankton community and more sensitive to environmental changes, and the degree of variation was greater. The higher the degree of eutrophication of the reservoir, the more obvious this phenomenon. VPA showed that the changes in plankton communities in Huaxi Reservoir and Hailong Reservoir were mainly influenced by water temperature and eutrophication factors. The changes in planktonic community in Goupitan Reservoir were mainly influenced by water temperature and chemical factors. The driving factors of Huaxi Reservoir were water temperature, TP, permanganate index, and SD. The driving factors of Goupitan Reservoir were water temperature, NO3-- N, and pH. The driving factors of Hailong Reservoir were water temperature and TP. Nutrients and water temperature were the main factors affecting the stability of plankton communities in reservoirs.


Asunto(s)
Monitoreo del Ambiente , Fitoplancton , Zooplancton , Fitoplancton/crecimiento & desarrollo , Fitoplancton/clasificación , Zooplancton/clasificación , China , Animales , Rotíferos/crecimiento & desarrollo , Calidad del Agua , Eutrofización , Copépodos/crecimiento & desarrollo , Cladóceros/crecimiento & desarrollo , Plancton/clasificación , Cianobacterias/crecimiento & desarrollo , Dinámica Poblacional
18.
PLoS One ; 19(7): e0305465, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39018345

RESUMEN

Modern urban dynamics are increasingly shaped by the interplay between economic policy and urban planning, yet often lack an integrated approach. This study bridges this gap by examining the dynamic equilibrium between these two realms using the "Oscillation and Wave Framework." Specifically, we focus on the impact of variations in congestion parameter λ on urban sectoral spatial distribution and population dynamics. Our approach utilizes an advanced agent-based model to simulate interactions within an urban economic landscape, offering a detailed analysis of the relationship between agglomeration economies and congestion diseconomies. The results highlight the significant influence of congestion parameter adjustments on urban patterns, particularly in terms of cluster density and development. Therefore, this study not only provides a deeper understanding of the intricate balance between economic and urban planning factors but also emphasizes the necessity of incorporating these insights into urban planning and policy formulation for sustainable urban development. The findings also have important practical implications for addressing the dynamic complexities of urban environments, especially the interactions between different industries and their role in shaping urban structures.


Asunto(s)
Planificación de Ciudades , Dinámica Poblacional , Planificación de Ciudades/economía , Humanos , Población Urbana , Modelos Teóricos , Ciudades , Urbanización , Modelos Económicos
19.
Ecol Lett ; 27(7): e14481, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39022847

RESUMEN

Ecological communities are inherently dynamic: species constantly turn over within years, months, weeks or even days. These temporal shifts in community composition determine essential aspects of species interactions and how energy, nutrients, information, diseases and perturbations 'flow' through systems. Yet, our understanding of community structure has relied heavily on static analyses not designed to capture critical features of this dynamic temporal dimension of communities. Here, we propose a conceptual and methodological framework for quantifying and analysing this temporal dimension. Conceptually, we split the temporal structure into two definitive features, sequence and duration, and review how they are linked to key concepts in ecology. We then outline how we can capture these definitive features using perspectives and tools from temporal graph theory. We demonstrate how we can easily integrate ongoing research on phenology into this framework and highlight what new opportunities arise from this approach to answer fundamental questions in community ecology. As climate change reshuffles ecological communities worldwide, quantifying the temporal organization of communities is imperative to resolve the fundamental processes that shape natural ecosystems and predict how these systems may change in the future.


Asunto(s)
Cambio Climático , Ecosistema , Factores de Tiempo , Biota , Modelos Biológicos , Ecología/métodos , Dinámica Poblacional
20.
Sci Total Environ ; 946: 174342, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38960173

RESUMEN

Pollution is an integral part of global environmental change, yet the combined and interactive effects of pollution and climate on terrestrial ecosystems remain inadequately understood. This study aims to explore whether pollution alters the impacts of ambient air temperature on the population dynamics of herbivorous insects. Between 1995 and 2005, we studied populations of two closely related moths, Eriocrania semipurpurella and E. sangii, at eight sites located 1 to 64 km from a large copper­nickel smelter in Monchegorsk, Russia. We found that pollution and temperature influence the performance of Eriocrania larvae mining in the leaves of mountain birch, Betula pubescens var. pumila, through multiple pathways. This is evident from the unconsistent changes observed in larval and frass weight, mine area, and leaf size. We found increases in both leaf quality and larval weight with decreasing pollution levels at both spatial and temporal scales and attributed these to the impact of sulphur dioxide, rather than trace elements (nickel and copper). The quality of birch leaves increased with spring (May) temperatures, enabling Eriocrania larvae to achieve greater weight while consuming less biomass. During the larval growth period (early June to early July), Eriocrania larvae increased their consumption with rising temperatures, presumably to compensate for increased metabolic expenses. Contrary to our expectations, the per capita rate of population change did not correlate with larval weight and did not vary along the pollution gradient. Nevertheless, we detected interactive effects of pollution and climate on the rate of population change. This rate decreased with rising winter temperatures in slightly polluted and unpolluted sites but remained unchanged in heavily polluted sites. We conclude that pollution disrupts mechanisms regulating the natural population dynamics of Eriocrania moths.


Asunto(s)
Contaminantes Atmosféricos , Larva , Mariposas Nocturnas , Dinámica Poblacional , Temperatura , Animales , Larva/crecimiento & desarrollo , Larva/efectos de los fármacos , Mariposas Nocturnas/fisiología , Mariposas Nocturnas/crecimiento & desarrollo , Mariposas Nocturnas/efectos de los fármacos , Federación de Rusia , Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Monitoreo del Ambiente , Betula/efectos de los fármacos , Betula/crecimiento & desarrollo , Hojas de la Planta
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