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1.
Environ Sci Pollut Res Int ; 28(3): 2765-2778, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32892284

RESUMO

China is the most populous country in the world, and the pollution caused by the excessive population should not be underestimated. In recent years, China's population growth rate began to decline. Since 2003, the growth rate has dropped below 6‰, but the population base is still huge. This paper aims to study the influence of population structure on pollutant discharge. Using the improved STIRPAT model, we studied the panel data of 31 provinces from 2003 to 2017 to study the impact of population on pollutant discharge from the perspectives of gender, aging and urbanization. The results show that population affects pollutant discharge through three effects, among which gender effect and urbanization effect increase pollutant discharge, and gender effect has a greater impact on pollutant discharge than urbanization effect. But the aging effect helps to reduce pollutant discharge during the study period. The results also show that population size contributes to pollutant discharge in the east, west, and northeast. However, population size had no significant effect on pollutant discharge in the middle part. Therefore, it is necessary to consider the difference of population impact when making environmental policy effectively. Finally, some special issues are briefly discussed.


Assuntos
Poluentes Ambientais , China , Poluição Ambiental , Crescimento Demográfico , Urbanização
2.
Sci Total Environ ; 754: 142380, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254886

RESUMO

Although atmospheric concentrations of many conventional persistent organic pollutants (POPs) have decreased in the Arctic over the past few decades, levels of most POPs and mercury remain high since the 1990s or start to increase again in Arctic areas, especially polar bears. So far, studies generally focused on individual effects of POPs, and do not directly link POP concentrations in prey species to population-specific parameters. In this study we therefore aimed to estimate the effect of legacy POPs and mercury on population growth rate of nineteen polar bear subpopulations. We modelled population development in three scenarios, based on species sensitivity distributions (SSDs) derived for POPs based on ecotoxicity data for endothermic species. In the first scenario, ecotoxicity data for polar bears were based on the HC50 (the concentration at which 50% of the species is affected). The other two scenarios were based on the HC5 and HC95. Considerable variation in effects of POPs could be observed among the scenarios. In our intermediate scenario, we predicted subpopulation decline for ten out of 15 polar bear subpopulations. The estimated population growth rate was least reduced in Gulf of Boothia and Foxe Basin. On average, PCB concentrations in prey (in µg/g toxic equivalency (TEQ)) posed the largest threat to polar bear subpopulations, with negative modelled population growth rates for the majority of subpopulations. We did not find a correlation between modelled population changes and monitored population trends for the majority of chemical-subpopulation combinations. Modelled population growth rates increased over time, implying a decreasing effect of PCBs, DDTs, and mercury. Polar bear subpopulations are reportedly still declining in four out of the seven subpopulations for which sufficient long-term monitoring data is available, as reported by the IUCN-PBSG. This implies that other emerging pollutants or other anthropogenic stressors may affect polar bear subpopulations.


Assuntos
Poluentes Ambientais , Bifenilos Policlorados , Ursidae , Animais , Regiões Árticas , Monitoramento Ambiental , Poluentes Ambientais/análise , Poluentes Ambientais/toxicidade , Bifenilos Policlorados/análise , Bifenilos Policlorados/toxicidade , Crescimento Demográfico
3.
Pest Manag Sci ; 77(1): 217-223, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32677316

RESUMO

BACKGROUND: White and colored fiber cotton cultivars have been developed to increase production and opportunities for family farming. The broad mite, Polyphagotarsonemus latus (Banks) is an important pest in cotton crops, nevertheless, different cotton cultivars may influence its host selection and population growth. For P. latus control, acaricides application is commonly performed, although less is known about the sublethal effects of these products. Thus, the host preference and instantaneous rate of increase (ri ) of P. latus were evaluated on white and colored cotton cultivars, as well as the lethal and sublethal effects of acaricides through mortality tests and population growth. RESULTS: In free-choice tests to evaluate host preference among white and colored cotton cultivars, no preference was observed for P. latus. The instantaneous ri values were positive for all tested cultivars, however, differences were observed between the colored BRS Rubi and the white BRS 201. The population growth of P. latus decreased with increasing concentrations of the acaricides abamectin, spirodiclofen, azadirachtin and spiromesifen. Nevertheless, azadirachtin and spiromesifen presented positive ri values even at the highest lethal concentrations (LC90 ), while abamectin and spirodiclofen provided negative ri values of P. latus from LC90 and LC70 , respectively. CONCLUSION: No host preference of P. latus was observed among white and colored cotton cultivar. Abamectin and spirodiclofen presented relevant sublethal effects that should be considered for the integrated management of this pest.


Assuntos
Acaricidas , Ácaros , Acaricidas/farmacologia , Animais , Gossypium , Crescimento Demográfico
4.
Adv Mar Biol ; 87(1): 1-30, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33293007

RESUMO

An unequivocal link exists between human population density and environmental degradation, both in the near field (local impacts) and far field (impacts due to teleconnections). Human population is most widely predicted to reach 9-11 billion by 2100, when the demographic transition is expected in all but a handful of countries. Strongest population growth is in the tropics, where coral reefs face dense human population and concomitant heavy usage. In most countries, >50% will be urbanized but growth of rural population and need for food in urban centres will not alleviate pressure on reef resources. Aquaculture will alleviate some fishing pressure, but still utilizes reef surface and is also destructive. Denser coastal populations and greater wealth will lead to reef degradation by coastal construction. Denser populations inland will lead to more runoff and siltation. Effects of human perturbations can be explored with metapopulation theory since they translate to increases in patch-mortality and decreases in patch-colonization (=regeneration). All such changes will result in a habitat with overall fewer settled patches, so fewer live reefs. If rescue effects are included, bifurcations in system dynamics will allow for many empty patches and, depending on system state relative to stable and unstable equilibria, a part-empty system may either trend towards stability at higher patch occupancy or extinction. Thus, unless the disturbance history is known, it may be difficult to assess the direction of system trajectory-making management difficult. If habitat is decreased by destruction, rescue effects become even more important as extinction-debt, accumulated by efficient competitors with weaker dispersal ability, is realized. Easily visible trends in human population dynamics combined with well-established and tested ecological theory give a clear, intuitive, yet quantifiable guide to the severity of survival challenges faced by coral reefs. Management challenges and required actions can be clearly shown and, contrary to frequent claims, no scientific ambiguity exists with regards to the serious threat posed to coral reefs by humankind's continued numerical increase.


Assuntos
Recifes de Corais , Crescimento Demográfico , Animais , Antozoários , Conservação dos Recursos Naturais , Humanos , Dinâmica Populacional
5.
Proc Biol Sci ; 287(1938): 20201182, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33143582

RESUMO

Density-dependent and extrinsic mortality are predicted to accelerate reproductive maturation. The first 5 years of life is a proposed sensitive period for life-history regulation. This study examines the ways in which local mortality during this sensitive period was related to subsequent marriage timing in nineteenth-century Belgium (n women = 11 892; n men = 14 140). Local mortality during the sensitive period was inversely associated with age at first marriage for men and women controlling for literacy, occupational status, population growth and migration. Cox regression indicated decreased time to marriage for women (HR = 1.661, 95% CI: 1.542-1.789) and men (HR = 1.327, 95% CI: 1.238-1.422) from high mortality municipalities. Rising population growth rates were associated with earlier marriage for men and women. Migration in general was associated with later marriage for men and women. Consistent with life-history predictions, harsh ecological conditions during early life such as famine coincided with earlier marriage.


Assuntos
Fome Epidêmica/tendências , Mortalidade/tendências , Adulto , Bélgica/epidemiologia , Demografia , Países Desenvolvidos , Emigração e Imigração , Feminino , Fertilidade , Humanos , Masculino , Dinâmica Populacional , Crescimento Demográfico , Fatores Socioeconômicos
7.
J Insect Sci ; 20(5)2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33080018

RESUMO

In order to investigate the effects of artificial diets on the population growth of root maggot Bradysia impatiens, its population growth parameters were assayed on eight artificial diets (Diet 1, D2, D3, D4, D5, D6, D7, and D8). Results showed that developmental duration from egg to pupa was successfully completed on all eight artificial diets. However, the egg to pupal duration was shortest, while the survival rate of four insect stages was lowest when B. impatiens was reared on D1. When B. impatiens was reared on D7 and D8, the survival rate, female longevity, and female oviposition were higher than those reared on other diets. When B. impatiens was reared on D7, the intrinsic rate of increase (rm = 0.19/d), net reproductive rate (R0 = 39.88 offspring per individual), and finite rate of increase (λ = 1.21/d) were higher for its population growth with shorter generation time (T = 19.49 d) and doubling time (Dt = 3.67 d). The findings indicate that the D7 artificial diet is more appropriate for the biological parameters of B. impatiens and can be used an indoor breeding food for population expansion as well as further research. We propose that vitamin C supplement added to the D7 is critical for the improvement of the B. impatiens growth.


Assuntos
Dieta , Dípteros/crescimento & desenvolvimento , Animais , Larva/crescimento & desenvolvimento , Longevidade , Oviposição , Crescimento Demográfico , Pupa/crescimento & desenvolvimento , Análise de Sobrevida , Vitaminas
8.
Sci Total Environ ; 748: 141346, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33113687

RESUMO

Demographic trends will play a role in determining the magnitude of climate disruption and the ability of societies to adapt to it. Yet policy makers largely ignore the potential of fertility changes and population growth when designing policies to limit climate disruption and lessen its impacts. Here we argue that rights-based policy interventions could decrease fertility rates to levels consistent with low population pathways. We review country and global level studies that explore the effects of low population pathways on climate change mitigation and adaptation. We then provide rights-based policy recommendations, such as the expansion of voluntary family planning programs that incorporate elements from successful past programs, and highlight current research gaps. In concert with policies that end fossil fuel use and incentivize sustainable consumption, humane policies that slow population growth should be part of a multifaceted climate response. These policies require attention from scientists, policy analysts and politicians.


Assuntos
Mudança Climática , Crescimento Demográfico , Aclimatação , Coeficiente de Natalidade , Fertilidade
9.
PLoS Biol ; 18(10): e3000894, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33064736

RESUMO

Developing a thorough understanding of how ectotherm physiology adapts to different thermal environments is of crucial importance, especially in the face of global climate change. A key aspect of an organism's thermal performance curve (TPC)-the relationship between fitness-related trait performance and temperature-is its thermal sensitivity, i.e., the rate at which trait values increase with temperature within its typically experienced thermal range. For a given trait, the distribution of thermal sensitivities across species, often quantified as "activation energy" values, is typically right-skewed. Currently, the mechanisms that generate this distribution are unclear, with considerable debate about the role of thermodynamic constraints versus adaptive evolution. Here, using a phylogenetic comparative approach, we study the evolution of the thermal sensitivity of population growth rate across phytoplankton (Cyanobacteria and eukaryotic microalgae) and prokaryotes (bacteria and archaea), 2 microbial groups that play a major role in the global carbon cycle. We find that thermal sensitivity across these groups is moderately phylogenetically heritable, and that its distribution is shaped by repeated evolutionary convergence throughout its parameter space. More precisely, we detect bursts of adaptive evolution in thermal sensitivity, increasing the amount of overlap among its distributions in different clades. We obtain qualitatively similar results from evolutionary analyses of the thermal sensitivities of 2 physiological rates underlying growth rate: net photosynthesis and respiration of plants. Furthermore, we find that these episodes of evolutionary convergence are consistent with 2 opposing forces: decrease in thermal sensitivity due to environmental fluctuations and increase due to adaptation to stable environments. Overall, our results indicate that adaptation can lead to large and relatively rapid shifts in thermal sensitivity, especially in microbes for which rapid evolution can occur at short timescales. Thus, more attention needs to be paid to elucidating the implications of rapid evolution in organismal thermal sensitivity for ecosystem functioning.


Assuntos
Adaptação Fisiológica , Evolução Biológica , Crescimento Demográfico , Temperatura , Bases de Dados como Assunto , Padrões de Herança/genética , Modelos Biológicos , Filogenia , Fitoplâncton/fisiologia , Células Procarióticas/metabolismo , Especificidade da Espécie
10.
PLoS One ; 15(10): e0240592, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33075087

RESUMO

The security and socioeconomic development of China's border areas are of great significance to the nation and the wider world. Using census, statistical, digital elevation model (DEM) and network data, this paper employs visual analysis to capture population distribution patterns in China's 131 border counties from 1982 to 2010. Multiple stepwise regression is carried out to identify the influencing factors of population dynamics in border regions. The main findings include: China's most heavily populated border areas are primarily in the northeast, northwest, and the Guangxi-Yunnan region, while rapid growth of population is found in western Inner Mongolia, southwest Xinjiang, northwest Tibet, and southern Yunnan. Given the increasingly market-oriented migration mechanism, the national reclamation policy has been no longer effective in population attraction in the new century. Education has significantly lowered and will continuously lower the fertility rate in remote border areas. The factors influencing population growth show a remarkable regional heterogeneity along China's long border.


Assuntos
Desenvolvimento Econômico , Emigração e Imigração/tendências , Dinâmica Populacional , Crescimento Demográfico , Censos , China/epidemiologia , Demografia/economia , Países em Desenvolvimento/economia , Emprego/economia , Geografia/economia , Humanos , Alfabetização , Políticas , Densidade Demográfica , Medidas de Segurança , Tibet/epidemiologia
11.
Ecol Lett ; 23(11): 1664-1672, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32869431

RESUMO

Phenotypic plasticity is a prominent mechanism for coping with variable environments, and a key determinant of extinction risk. Evolutionary theory predicts that phenotypic plasticity should evolve to lower levels in environments that fluctuate less predictably, because they induce mismatches between plastic responses and selective pressures. However, this prediction is difficult to test in nature, where environmental predictability is not controlled. Here, we exposed 32 lines of the halotolerant microalga Dunaliella salina to ecologically realistic, randomly fluctuating salinity, with varying levels of predictability, for 500 generations. We found that morphological plasticity evolved to lower degrees in lines that experienced less predictable environments. Evolution of plasticity mostly concerned phases with slow population growth, rather than the exponential phase where microbes are typically phenotyped. This study underlines that long-term experiments with complex patterns of environmental change are needed to test theories about population responses to altered environmental predictability, as currently observed under climate change.


Assuntos
Adaptação Fisiológica , Evolução Biológica , Meio Ambiente , Fenótipo , Crescimento Demográfico
12.
Environ Monit Assess ; 192(9): 608, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32865639

RESUMO

Population growth, which is the main source of the biggest problems of the world today, combined with migration from rural areas to urban centers, causes the urban centers to be even more concentrated. This necessitates the opening of new residential areas in many city centers, but new residential areas are mostly determined by the decisions of local authorities, who may not base their decisions on scientific data. With the wrong area selection, ordinary natural events can be potentially catastrophic. Such events can result in large numbers of casualties and material damage every year. In this study, an example of applying a method for location selection using various parameters has been realized. The study focuses on Bafra, Turkey (the study area). Risk maps were created in terms of floods and overflows; maps of regions and high-voltage power transmission lines that enjoy a protected area status; and maps of regions in terms of biocomfort suitability. As a result of the evaluation made according to these criteria, it is calculated that only 1.96% of the total working area is suitable for use as a residential area. In relevant literature studies, it was observed that the studies related to the selection of residential areas were carried out only depending on a single standard or criterion. Some suggested biocomfort, and others used vulnerability to risks such as landslide, flood, and earthquakes as their main principle. Studies based on multi-criteria were generally used for purposes such as solid waste site selection and determination of the road routes. The study aims to shed light on the multi-criteria method in an attempt to standardize it in regional planning studies and to inspire similar studies in which different criteria can be used to achieve the maximum efficiency.


Assuntos
Monitoramento Ambiental , Crescimento Demográfico , Resíduos Sólidos , Cidades , Inundações , Turquia
13.
Environ Monit Assess ; 192(10): 631, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32902699

RESUMO

In recent years, it has been difficult to establish a supply-demand balance between urban growth, increasing population, and existing water resources in many countries. In this study, the Bodrum Peninsula, which is an important tourism center for Turkey, was examined in terms of the relationship between the urban growth of the peninsula, population projections, the need for drinking and potable water, and the availability of the existing water resources. Using the Geographic Information System, it has been determined that the urban growth of the peninsula increased by 11.36% between 1985 and 2010. Urban growth is mostly concentrated in the coastal areas where 2 houses are densely built. The population is expected to increase approximately six times between 2010 and 2060. The amount of drinking and potable water required according to the population projection is 12.38, 26.50, 69.12, and 109.50 hm3/year for 2010, 2030, 2050, and 2060 respectively. The existing water resources of the peninsula will be able to meet the requirements until 2030. In order to meet the water needs of the peninsula until 2055, the Bozalan and Gökçeler dams located nearby as well as the Namnam dam located at mid-range to the peninsular should be built. It is not possible to meet the water needs of the peninsula in 2060 with just the near and medium distance water resources. However, by supplying water from the Akköprü dam located at a further distance, it is possible that 2060 water needs can be met.


Assuntos
Crescimento Demográfico , Recursos Hídricos , Conservação dos Recursos Naturais , Monitoramento Ambiental , Turquia , População Urbana , Abastecimento de Água
14.
Curr Biol ; 30(15): R849-R857, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32750338

RESUMO

There is no doubt that the novel coronavirus SARS-CoV-2 that causes COVID-19 is mutating and thus has the potential to adapt during the current pandemic. Whether this evolution will lead to changes in the transmission, the duration, or the severity of the disease is not clear. This has led to considerable scientific and media debate, from raising alarms about evolutionary change to dismissing it. Here we review what little is currently known about the evolution of SARS-CoV-2 and extend existing evolutionary theory to consider how selection might be acting upon the virus during the COVID-19 pandemic. Although there is currently no definitive evidence that SARS-CoV-2 is undergoing further adaptation, continued evidence-based analysis of evolutionary change is important so that public health measures can be adjusted in response to substantive changes in the infectivity or severity of COVID-19.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Adaptação Biológica/genética , Animais , Infecções Assintomáticas , Betacoronavirus/genética , Betacoronavirus/patogenicidade , Evolução Biológica , Infecções por Coronavirus/transmissão , Pleiotropia Genética , Variação Genética , Humanos , Mutação , Pandemias , Pneumonia Viral/transmissão , Crescimento Demográfico , Seleção Genética , Zoonoses
15.
Oecologia ; 193(4): 889-901, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32803340

RESUMO

Amphibian life history traits are affected by temperature and precipitation. Yet, connecting these relationships to population growth, especially for multiple populations within a species, is lacking and precludes our understanding of amphibian population dynamics and distributions. Therefore, we constructed integral projection models for five populations along an elevational gradient to determine how climate and season affect population growth of a terrestrial salamander Plethodon montanus and the importance of demographic vital rates to population growth under varying climate scenarios. We found that population growth was typically higher at the highest elevation compared to the lower elevations, whereas varying inactive season conditions, represented by the late fall, winter and early spring, produced a greater variation in population growth than varying active season conditions (late spring, summer, and early fall). Furthermore, survival and growth were consistently more important, as measured by elasticity, compared to fecundity, and large females had the greatest elasticity compared to all other body sizes. Our results suggest that changing inactive season conditions, especially those that would affect the survival of large individuals, may have the greatest impact on population growth. We recommend future experimental studies focus on the inactive season to better elucidate the mechanisms by which these conditions can affect survival.


Assuntos
Mudança Climática , Crescimento Demográfico , Clima , Feminino , Dinâmica Populacional , Estações do Ano
16.
J Nurs Manag ; 28(7): 1473-1480, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32786163

RESUMO

AIMS: This scoping review discusses two telecommuting options to advance scholarship regarding Baby-Boomer nurses' delayed retirement and to extend their contribution to bedside nursing. BACKGROUND: Peer-reviewed studies published in the 15 years before COVID-19 indicate that Baby-Boomer nurses' retirement will increase the global nursing shortage. However, three international trends have affected Baby-Boomer nurses' decision to delay their retirement. EVALUATION: This review observed the scoping review framework. KEY ISSUES: COVID-19 further disrupts the current understanding of Baby-Boomer nurses' retirement as they recognize COVID-19's impact on health care systems and younger nurses. Technological advancements and the changing needs of health care delivery have made telecommuting a practical possibility. CONCLUSION: Baby-Boomer nurses can leverage alternative work arrangements to meet their needs and to contribute to clinical practice through telecommuting. This approach extends Baby-Boomer nurses' careers and creates a resource for bedside nurses. IMPLICATIONS FOR NURSING MANAGEMENT: Clinical experience matters at the bedside. Telecommuting maximizes the retention of Baby-Boomer nurses' clinical expertise to benefit patients and to socialize bedside nurses. Baby-Boomer nurses can contribute to patient monitoring as well as patient education and counselling through telehealth. They can also provide asynchronous and synchronous telementoring to bedside nurses.


Assuntos
Enfermeiras e Enfermeiros/estatística & dados numéricos , Demografia , Humanos , Enfermeiras e Enfermeiros/provisão & distribução , Crescimento Demográfico , Aposentadoria/estatística & dados numéricos , /estatística & dados numéricos
17.
Ecotoxicol Environ Saf ; 203: 110998, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32778532

RESUMO

Relative ecotoxicity of approved neonicotinoids (i.e. imidacloprid, clothianidin, acetamiprid, thiacloprid, thiamethoxam and dinotefuran) and diamides (i.e. chlorantraniliprole, cyantraniliprole and flubendiamide) was examined on population growth parameters of Zygogramma bicolorata Pallister on parthenium under laboratory conditions at 27 ± 1 °C, 65 ± 5% relative humidity and 10 L : 14D photoperiod. The dose of all tested insecticides in the bioassay procedure was within a minimum range of their recommended field rate. In acute toxicity trial, imidacloprid caused highest rate of mortality in treated adults of Z. bicolorata, however, it was lowest in flubendiamide treatment followed by cyantraniliprole and chlorantraniliprole. Further, based on toxicity coefficient (E) value in acute toxicity trial, all were classified as harmful (H) and diamides were classified as moderately harmful (MH) as per IOBC classification. Moreover, chronic toxicity trials were carried out through life table response experiments (LTREs) in the F1 progeny of acute toxicity experienced group. Prolonged development with the highest mortality was evident in as compared to diamides. Furthermore, population growth parameters i.e. potential fecundity (Pf), natality rate (mx), intrinsic rate of increase (rm), net reproductive rate (R0) and finite rate of increase (λ) was greatly reduced in Z. bicolorata treated with neonicotinoids as compared with diamides. However, mean generation time (Tc), corrected generation time (τ) and the doubling time (DT) was prolonged in neonicotinoids followed by diamides. Furthermore, proportion of females was greatly reduced (0.43-0.48 females) in neonicotinoids as comparison to diamides (0.53-0.55 females) and control (0.67 females). On the basis of ecotoxicity trials, the tested neonicotinoids were highly toxic to Z. bicolorata than diamides. Therefore, diamide insecticides could be used with Z. bicolorata, however, for validation experimentation need to be done under natural field conditions.


Assuntos
Besouros/efeitos dos fármacos , Diamida/toxicidade , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Animais , Besouros/fisiologia , Ecotoxicologia , Feminino , Crescimento Demográfico , Testes de Toxicidade Aguda
19.
Sci Rep ; 10(1): 10613, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32606337

RESUMO

We study the dynamics of a ring of patches with vegetation-prey-predator populations, coupled through interactions of the Lotka-Volterra type. We find that the system yields aperiodic, recurrent and rare explosive bursts of predator density in a few isolated spatial patches from time to time. Further, the global predator biomass also exhibits sudden uncorrelated occurrences of large deviations from the mean as the coupled system evolves. The maximum value of the predator population in a patch, as well as the maximum value of the predator biomass, increases with coupling strength. These trends are further corroborated by fits to Generalized Extreme Value distributions, where the location and scale factor of the distribution increases markedly with coupling strength, indicating the crucial role of coupling interactions in the generation of extreme events. These results indicate how occurrences of extremely large predator populations can emerge in coupled population dynamics, and in a more general context they suggest a generic class of deterministic nonlinear systems that can naturally exhibit extreme events.


Assuntos
Biomassa , Cadeia Alimentar , Modelos Biológicos , Comportamento Predatório , Animais , Dinâmica Populacional , Crescimento Demográfico
20.
Environ Sci Pollut Res Int ; 27(30): 37626-37644, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32607999

RESUMO

It is an overwhelming concern that increases in global average temperature lead to serious consequences on the natural environment in the form of deteriorating water resource quality and damaging healthcare sustainability agenda. The sustainable innovation forum (COP21) shows a high concern on climate changes and suggested to reduce global average temperature less than 2 °C. The study brings an idea from the stated theme and analyzed the relationship between climate change and water resource quality in order to redesign economic and environmental policies to improve water quality and healthcare sustainability in the context of Pakistan. The country has serious issues regarding the provision of safe drinking water, improved water resource quality, and healthcare sustainability, which can be achieved by sustainable policies to handle the extreme temperature in Pakistan. The study employed simultaneous generalized method of moments (GMM) technique in order to estimate parameters of the study during the period of 1980-2016. The results show that energy demand and industry value added substantially decrease water resource quality (WRQ), while agriculture value added and per capita income significantly increase WRQ in a country. The other regression apparatus, where health expenditures serve as the response variable, shows that average temperature, industry value added, population growth, and foreign direct investment (FDI) inflows significantly increase healthcare expenditures while WRQ has a negative impact on healthcare expenditures in a country. The final regression model shows that average temperature and per capita income decrease, while WRQ and industrial value added increase mortality rate in a country. The overall results confirm that WRQ affected by climate change, energy demand, and population growth that need sustainable water resource policies in order to achieve long-term sustained growth. The climate actions required more policy instruments to combat environmental challenges that should support healthcare sustainability agenda across the globe.


Assuntos
Desenvolvimento Econômico , Recursos Hídricos , Dióxido de Carbono/análise , Paquistão , Crescimento Demográfico , Temperatura , Qualidade da Água
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