Search results for "Population growth"
showing 10 items of 109 documents
Optimal growth and land preservation
1997
A model of optimal economic growth with a constant population subject to a constraint on the availability of land is presented. It takes account of the dual character of land as a production factor and as a consumption good (environmental amenities) by determining the optimal intertemporal allocation of land between productive and recreational uses. An extension of the analysis for the case of a growing population with endogenous growth based on human capital accumulation shows that if the rate of discount is not very low then there exists a set of balanced growth paths compatible with a constant allocation of land. En este trabajo se presenta un modelo de crecimiento económico óptimo con u…
100 Million Filipinos
2017
The Philippine archipelago, with more than 100 million inhabitants, is the 12th most populous in the world, one the fastest growing and youngest countries in Asia, and will soon overtake an aging Japan. Causes of the high rate of population growth include the teachings of the influential Philippine Catholic Church (no divorce, contraception or abortion) and the active sexual life of young Filipinos. Many women become pregnant at a very early age, soon after puberty. The country has not developed population control policies as some other countries (Thailand, China) have. Therefore it has a very young population with few elderly people, a situation that may be good for the economy (demographi…
Optimal Population Growth as an Endogenous Discounting Problem: The Ramsey Case
2018
International audience; This paper revisits the optimal population size problem in a continuous time Ramsey setting with costly child rearing and both intergenerational and intertemporal altruism. The social welfare functions considered range from the Millian to the Benthamite. When population growth is endogenized, the associated optimal control problem involves an endogenous effective discount rate depending on past and current population growth rates, which makes preferences intertemporally dependent. We tackle this problem by using an appropriate maximum principle. Then we study the stationary solutions (balanced growth paths) and show the existence of two admissible solutions except in…
Determinants of Sub-Sovereign Government Ratings In Europe
2017
The aim of this paper is to identify the determinantsof the rating assigned to sub-sovereignentities in Germany, Austria, Belgium, France,Italy and Spain, using a total of 92 territorial entitiesfor the 1989-2012 period. Multinomial orderedprobit estimation models were estimatedfor each specifi cation and agency.We conclude that the country’s rating is oneof the most important determinants of regionalgovernment’s ratings with a positive infl uence(as expected), and that the country debt/GDPratio is a stronger determinant for regions thantheir own indebtedness with a negative sign.Other relevant variables are population growthrate, unemployment rate, elderly people weight,regional public exp…
A Holistic Vision of Smart Cities: An Opportunity for a Big Change
2016
The depletion of energy resources on the one hand, and the population growth on the other, forced the society at all levels (local, national and international) to turn its attention to the identification of new forms of protection of the environment and the waste reduction for a new eco-sustainable way of living. The process of massive urbanization already in place, exacerbated by the movement of large masses of people in search of a more human form of life, is putting severely under test the livability within our cities, bringing out the inefficiency of existing management and organization models. Daisaku Ikeda said: “Certainly, the density of urban populations means that problems are conc…
Population changes in Czech passerines are predicted by their life-history and ecological traits
2010
A species’ susceptibility to environmental change might be predicted by its ecological and life-history traits. However, the effects of such traits on long-term bird population trends have not yet been assessed using a comprehensive set of explanatory variables. Moreover, the extent to which phylogeny affects patterns in the interspecific variability of population changes is unclear. Our study focuses on the interspecific variability in long-term population trends and annual population fluctuations of 68 passerine species in the Czech Republic, assessing the effects of eight life-history and five ecological traits. Ordination of life-history traits of 68 species revealed a life-history grad…
Optimal Sustainable Policies Under Pollution Ceiling: the Demographic Side
2014
AD; International audience; We study optimal sustainable policies in a benchmark logistic world (where both population and technological progress follow logistic laws of motion) subject to a pollution ceiling. The main policy in the hands of the benevolent planner is pollution abatement, ultimately leading to the control of a dirtiness index as in the early literature of the limits to growth literature. Besides inclusion of demographic dynamics, we also hypothesize that population size affects negatively the natural regeneration or assimilation rate, as a side product of human activities (like increasing pollution, deforestation, ...). We first characterize optimal sustainable policies. Und…
Growth vs. Level Effect of Population Change on Economic Development: An Inspection into Human-Capital-Related Mechanisms
2011
This paper studies the different mechanisms and the dynamics through which demography is channeled to the economy. We analyze the role of demographic changes in the economic development process by studying the transitional and the long-run impact of both the rate of population growth and the initial population size on the levels of per capita human capital and income. We do that in an enlarged Lucas-Uzawa model with intergenerational altruism. In contrast to the existing theoretical literature, the long-run level effects of demographic changes, i.e. their impact on the levels of the variables along the balanced growth path, are deeply characterized in addition to the more standard long-run …
Sublethal zinc exposure has a detrimental effect on reproductive performance but not on the cyst hatching success of Artemia parthenogenetica
2008
The sublethal zinc toxicity to Artemia parthenogenetica as regards the possibility of colonization of zinc polluted salterns by means of cysts has been assessed by a cyst hatching assay and a life table approach. Emergence and hatching at different times as well as the whole hatching profile were taken as end-points for evaluating success of development. Demographic and reproductive parameters calculated according to the Lotka equation were used as an indicator of the chronic toxicity of the population. No adverse effects of waterborne zinc were found on hatching and emergence of cysts of A. parthenogenetica at any of the concentrations tested (0.01 mg/l, 0.1 mg/l, 0.5 mg/l, 1 mg/l, 5 mg/l)…
The role of community-based knowledge and local institutions in managing landslides on the slopes of Mount Elgon, Uganda
2015
The paper explores the degree to which community-based knowledge (CBK) and local institutions can be effective for disaster preparedness and management, based on a study carried out in Nametsi Parish, located on the slopes of Mount Elgon, in eastern Uganda. The study area has experienced innumerable landslides since 1933. Whereas a few of the landslides have not been disastrous, several others have had far-reaching effects on the livelihoods of people living in the area. This is attributed partly to the geographical setting, which makes the area difficult to access, and partly to socio-economic factors such as a high population growth rate and widespread poverty. Despite these aspects of vu…