scholarly journals THE IMPACT OF HUMAN FACTORS ON THE CHANGE IN VEGETATION COVER OF THE BE RIVER BASIN IN THE PERIOD FROM 2000 TO 2015

2020 ◽  
Vol 15 (9) ◽  
pp. 53
Author(s):  
Phan Văn Trung ◽  
Nguyễn Thám
Keyword(s):  
Growth Rate ◽  
Human Factors ◽  
Population Growth ◽  
River Basin ◽  
Vegetation Cover ◽  
Population Growth Rate ◽  
Mapping Method ◽  
Rapid Urbanization ◽  
Set Up ◽  
The Impact

 The Be river basin is located in the area with a rapid urbanization rate and a large immigrants proportion annually. Therefore, the population growth rate for the period from 2000 to 2015 in the river basin is up 3,53% which is 3,27 times as high as the population growth rate of Vietnam. These are the major causes leading to the fluctuation in vegetation cover of the Be river basin during over time. This research used methodologies including data collection, statistical analysis, mapping method and geographic information system to evaluate the impact of human factors to the vegetation cover fluctuation of the Be river basin in the period from 2000 to 2015. Based on the results of change map in the vegetation cover, a research group set up fluctuating matrix, analyze to clarify the vegetation coverfluctuation situation due to human’s impacts in the Be river basin in the period from 2000 to 2015. 

scholarly journals Fall supplemental feeding increases population growth rate of an endangered caribou herd

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10708
Author(s):  
Douglas C. Heard ◽  
Kathryn L. Zimmerman
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Population Growth Rate ◽  
Population Increase ◽  
Adult Survival ◽  
Management Approach ◽  
Annual Growth Rate ◽  
Supplemental Feeding ◽  
Management Actions ◽  
The Impact

Most woodland caribou (Rangifer tarandus caribou) populations are declining primarily because of unsustainable predation resulting from habitat-mediated apparent competition. Wolf (Canis lupus) reduction is an effective recovery option because it addresses the direct effect of predation. We considered the possibility that the indirect effects of predation might also affect caribou population dynamics by adversely affecting summer foraging behaviour. If spring and/or summer nutrition was inadequate, then supplemental feeding in fall might compensate for that limitation and contribute to population growth. Improved nutrition and therefore body condition going into winter could increase adult survival and lead to improved reproductive success the next spring. To test that hypothesis, we fed high-quality food pellets to free-ranging caribou in the Kennedy Siding caribou herd each fall for six years, starting in 2014, to see if population growth rate increased. Beginning in winter 2015–16, the Province of British Columbia began a concurrent annual program to promote caribou population increase by attempting to remove most wolves within the Kennedy Siding and the adjacent caribou herds’ ranges. To evaluate the impact of feeding, we compared lambdas before and after feeding began, and to the population trend in the adjacent Quintette herd over the subsequent four years. Supplemental feeding appeared to have an incremental effect on population growth. Population growth of the Kennedy Siding herd was higher in the year after feeding began (λ = 1.06) compared to previous years (λ = 0.91) and to the untreated Quintette herd (λ = 0.95). Average annual growth rate of the Kennedy Siding herd over the subsequent four years, where both feeding and wolf reduction occurred concurrently, was higher than in the Quintette herd where the only management action in those years was wolf reduction (λ = 1.16 vs. λ = 1.08). The higher growth rate of the Kennedy Siding herd was due to higher female survival (96.2%/yr vs. 88.9%/yr). Many caribou were in relatively poor condition in the fall. Consumption of supplemental food probably improved their nutritional status which ultimately led to population growth. Further feeding experiments on other caribou herds using an adaptive management approach would verify the effect of feeding as a population recovery tool. Our results support the recommendation that multiple management actions should be implemented to improve recovery prospects for caribou.

A Cross-national Study of Environmental Performance and Culture: Implications of the Findings and Strategies

2019 ◽  
Vol 20 (4) ◽  
pp. 1051-1068 ◽  
Author(s):  
Sushant Kumar ◽  
Vishlavath Giridhar ◽  
Pradip Sadarangani
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Environmental Performance ◽  
Population Growth Rate ◽  
Practical Implication ◽  
Environmental Law ◽  
Cultural Dimensions ◽  
National Study ◽  
Per Capita ◽  
The Impact

The study investigates the impact of culture on environmental performance across 78 countries. The article explores the possible relationship with two datasets of international indices: (a) the six dimensional index of national culture proposed by Hofstede and (b) the environmental performance index (EPI) published by Yale Center for Environmental Law and Policy. It is widely established that population and economic development of a country play significant role in the improvement of environmental performance. In our study, we examine the impact of population growth rate and per-capita gross domestic product (GDP) on environmental performance using structure equation modelling. The results show that environmental performance is significantly influenced by the culture of the country. Per-capita GDP and population growth rate have a positive and negative relationships on the environmental performance. By measuring the cultural dimensions and their impact on global environmental performance, countries could identify the favouring cultural dimensions and design appropriate strategy to optimize the environmental performance. The article proposes the practical implication of results and strategies to improve environmental performance. The study is among the first in studying the cultural dynamics on environment and identify its favourable and adverse relationships for an optimum strategy.

scholarly journals VARIETY, COMPETITION, AND POPULATION IN ECONOMIC GROWTH: THEORY AND EMPIRICS

2019 ◽  
pp. 1-28
Author(s):  
Alberto Bucci ◽  
Lorenzo Carbonari ◽  
Giovanni Trovato
Keyword(s):  
Economic Growth ◽  
Growth Rate ◽  
Population Growth ◽  
Population Growth Rate ◽  
Population Change ◽  
Finite Mixture Model ◽  
Growth Theory ◽  
Long Run ◽  
Gdp Growth Rate ◽  
The Impact

We provide aggregate macroeconomic evidence on how, in the long run, a diverse degree of complexity in production may affect not only the rate of economic growth, but also the correlation between the latter, population growth and the monopolistic (intermediate) markups. For a sample of Organisation for Economic Co-operation and Development (OECD) countries, we find that the impact of population change on economic growth is slightly positive. According to our theoretical model, this implies that the losses due to more complexity in production are lower than the corresponding specialization gains. Using a finite mixture model, we also classify the countries in the sample and verify for each cluster the impact that the population growth rate and the intermediate sector’s markups exert on the 5-year average real gross domestic product (GDP) growth rate.

scholarly journals Education and the Challenge of Poverty Alleviation in Nigeria

2020 ◽  
pp. 12-23
Author(s):  
R. Oke ◽  
S. I. Oladeji ◽  
O. P. Olofin
Keyword(s):  
Economic Growth ◽  
Growth Rate ◽  
Population Growth ◽  
Educational System ◽  
Population Growth Rate ◽  
Interactive Effect ◽  
Physical Capital ◽  
Employment Rate ◽  
Poverty Level ◽  
The Impact

Using Vector Autoregressive and Autoregressive Distributed Lag methods to examine the impact of education on poverty level and the interactive effect of education and economic growth on poverty level in Nigeria between 1985 and 2016, our results show that education promotes poverty level, instead of reducing it. We found significant cointegrating relationship among poverty, economic growth, education, employment rate, population growth rate, real physical capital formation, education level and real GDP. In the short-run, employment rate reduces poverty level, population growth rate increases poverty level both in the short and long-run. The results of interactive effect of economic growth and education on poverty growth show that jointly economic growth and education reduce poverty, although the results are not statistically significant. This shows that they have minimal impact on poverty level in Nigeria. Our findings may not be surprising, given the current slow-down in Nigeria educational system and the wide gap between the few rich and the larger poor. The study suggests improvement in Nigeria educational system so as promote employment and curb rising poverty level.

scholarly journals Delayed maturity does not offset negative impact afflicted by ectoparasitism in salmon

2021 ◽  
Author(s):  
Knut Wiik Vollset ◽  
Martin Krkosek
Keyword(s):  
Growth Rate ◽  
Life History ◽  
Body Size ◽  
Population Growth ◽  
Population Growth Rate ◽  
Negative Impact ◽  
Host Population ◽  
Sea Lice ◽  
Fish Farms ◽  
The Impact

AbstractThe negative effects of parasitism on host population dynamics may be mediated by plastic compensatory life-history changes in hosts. Theory predicts that hosts should shift their life-history towards early reproduction in response to virulent pathogens to maximize reproduction before death. However, for sublethal infections that affect growth, hosts whose fecundity is correlated with body size are predicted to shift towards delayed reproduction associated with larger body size and higher fecundity. This has been observed in Atlantic salmon and parasitic sea lice, via mark-recapture studies that recover mature fish from paired groups of control and parasiticide-treated smolts. We investigated whether such louse-induced changes to age at maturity can offset some of the negative effect of mortality on population growth rate in salmon using a structured population matrix model. Model results show that delayed maturity can partially compensate for reduced survival. However, this only occurs when marine survival is moderate to poor and growth conditions at sea are good. Also, the impact of delayed maturity on population growth when parameterizing the model with empirical data is negligible compared with effects of direct mortality. Our model thus suggests that management that works on minimizing the effect of sea lice from fish farms on wild salmon should focus mainly on correctly quantifying the effect of parasite-induced mortality during the smolt stage if the goal is to maximize population growth rate.

scholarly journals A Review of the Impact of Different Social Policy Incentives to Accelerate Population Growth Rate

2014 ◽  
Vol 1 (1) ◽  
Author(s):  
Samira Behboudi Gandevani ◽  
Saideh Ziaee ◽  
Farideh Khalajabadi Farahani
Keyword(s):  
Growth Rate ◽  
Social Policy ◽  
Population Growth ◽  
Population Growth Rate ◽  
Policy Incentives ◽  
The Impact

scholarly journals A Review of the Impact of Different Social Policy Incentives to Accelerate Population Growth Rate

2014 ◽  
Vol 1 (1) ◽  
Author(s):  
Samira Behboudi Gandevani ◽  
Saideh Ziaee ◽  
Farideh Khalajabadi Farahani
Keyword(s):  
Growth Rate ◽  
Social Policy ◽  
Population Growth ◽  
Population Growth Rate ◽  
Policy Incentives ◽  
The Impact

scholarly journals Modeling the impact of single-cell stochasticity and size control on the population growth rate in asymmetrically dividing cells

2021 ◽  
Vol 17 (6) ◽  
pp. e1009080
Author(s):  
Felix Barber ◽  
Jiseon Min ◽  
Andrew W. Murray ◽  
Ariel Amir
Keyword(s):  
Growth Rate ◽  
Cell Growth ◽  
Population Growth ◽  
Single Cell ◽  
Population Growth Rate ◽  
Asymmetric Cell Division ◽  
Size Control ◽  
Coarse Grained ◽  
Dividing Cells ◽  
The Impact

Microbial populations show striking diversity in cell growth morphology and lifecycle; however, our understanding of how these factors influence the growth rate of cell populations remains limited. We use theory and simulations to predict the impact of asymmetric cell division, cell size regulation and single-cell stochasticity on the population growth rate. Our model predicts that coarse-grained noise in the single-cell growth rate λ decreases the population growth rate, as previously seen for symmetrically dividing cells. However, for a given noise in λ we find that dividing asymmetrically can enhance the population growth rate for cells with strong size control (between a “sizer” and an “adder”). To reconcile this finding with the abundance of symmetrically dividing organisms in nature, we propose that additional constraints on cell growth and division must be present which are not included in our model, and we explore the effects of selected extensions thereof. Further, we find that within our model, epigenetically inherited generation times may arise due to size control in asymmetrically dividing cells, providing a possible explanation for recent experimental observations in budding yeast. Taken together, our findings provide insight into the complex effects generated by non-canonical growth morphologies.

scholarly journals Drivers of large-scale spatial demographic variation in a perennial plant

2020 ◽  
Author(s):  
Gesa Römer ◽  
Ditte M. Christiansen ◽  
Hendrik de Buhr ◽  
Kristoffer Hylander ◽  
Owen R. Jones ◽  
...  
Keyword(s):  
Growth Rate ◽  
Population Dynamics ◽  
Environmental Factors ◽  
Population Growth ◽  
Spatial Variation ◽  
Population Growth Rate ◽  
Forest Understory ◽  
Environmental Drivers ◽  
Vital Rates ◽  
The Impact

AbstractTo understand how the environment drives spatial variation in population dynamics, we need to assess the effects of a large number of potential drivers on the vital rates (survival, growth and reproduction), and explore these relationships over large geographical areas and long environmental gradients. In this study, we examined the effects of a broad variety of abiotic and biotic environmental factors, including intraspecific density, on the demography of the forest understory herb Actaea spicata between 2017 and 2019 at 40 sites across Sweden, including the northern range margin of its distribution. We assessed the effect of potential environmental drivers on vital rates using generalized linear mixed models (GLMMs), and then quantified the impact of each important driver on population growth rate (λ) using integral projection models (IPMs). Population dynamics of A. spicata were mostly driven by environmental factors affecting survival and growth, such as air humidity, soil depth and forest tree species composition, and thus those drivers jointly determined the realized niche of the species. Soil pH had a strong effect on the flowering probability, while the effect on population growth rate was relatively small. In addition to identifying specific drivers for A. spicata’s population dynamics, our study illustrates the impact that spatial variation in environmental conditions can have on λ. Assessing the effects of a broad range of potential drivers, as done in this study, is important not only to quantify the relative importance of different drivers for population dynamics but also to understand species distributions and abundance patterns.

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