Marriage Settlements

French couples may choose between two types of marriage settlements governing asset ownership after a divorce or inheritance: common property or separate property. A cooperative model considers the marriage contract as a means of providing for widowhood of the less endowed spouse. A second model addresses the probability of divorce and the production of a marriage good. The common property contract then becomes a means of inducing the wife to invest in the marriage good. Choice of contract, labor supply and fertility are simultaneous. Empirically we find that characteristics of the spouses such as relative age or differences in endowments influence the choice. So do the expected number of children and the wife's labor supply decision. This last decision is also shown to be influenced by the chosen settlement, while fertility is not.
JEL classification : J 12; J 4; K 12     

人口出生率地区差异的新兴古典经济学解释

新兴古典经济学中,经济组织的主要功能是降低分工生产中的交易费用.家庭区别于自由契约组织(市场与企业)的特征在于成员身份确定的血缘原则,而正是这一特征决定了家庭组织分工生产的功能在分工深化过程中从主到次的逐步退化规律.经济功能的退化导致平均家庭规模以及出生率持续下降,这一结论在中国省际数据的计量分析中得到了进一步的验证.     

Indigenous livelihoods, slash-and-burn agriculture, and carbon stocks in Eastern Panama

Improved crop–fallow systems in the humid tropics can simultaneously sequester atmospheric carbon emissions and contribute to sustainable livelihoods of rural populations. A study with an indigenous community in eastern Panama revealed a considerable biophysical potential for carbon offsets in small-scale slash-and-burn agriculture through longer fallow periods, improved fallow management, secondary forest development, and agricultural intensification. Based on soil and biomass carbon measurements, estimated annual sequestration rates amount to 0.3−3.7 t C ha^− 1 yr^− 1. Despite such potential, the economic benefits of initiatives aimed at sequestration of carbon in the community are likely to be rather unequally distributed within the community. Heterogeneity in livelihood strategies and uneven asset endowments among households – factors often overlooked in the ongoing carbon and sustainable development debate – are expected to strongly affect household participation. Indeed, only the better-endowed households that have also managed to diversify into more lucrative farm and non-farm activities are likely to be able to participate in and thus benefit from improved crop–fallow systems that capture carbon. Economic, ethical, institutional, and technical concerns need to be taken into account when designing community carbon management and investment plans.     

岩溶地区的水土流失及治理

滇、黔、桂的岩溶是我国最集中的分布区域。该地区的水土流失，不仅使农业生态环境迅速恶化，而且制约着农村经济的发展。本文就该地区水土流失的现状、危害，对其成因及治理对策作了探讨。     

Pollution Externalities in a Model of Endogenous Fertility and Growth

An endogenous growth model with human capital formation, pollution caused by production of consumption goods, and endogenous fertility decisions made by altruistic agents with infinite horizons is presented. Consequences for optimal policy of modelling fertility as an explicit decision variable are examined. Because ordinary lump-sum transfers to individuals are no longer neutral, either revenue from a pollution tax must be redistributed to dynasties (working as an implicit tax on child births), or lump-sum transfers must be supplemented with an explicit fertility tax. Alternatively, the government can avoid distortions of the fertility decisions by maintaining an appropriate public debt. When abatement is highly productive, it can be optimal to subsidize fertility in order to increase total production.     

Population Aging and the Possibility of a Middle-Income Trap in Asia

We present three conditions for a demography-driven middle-income trap and show that many economies in East, South, and Southeast Asia satisfy all of them. The conditions involve (1) the support ratio of workers to consumers has an impact on economic growth, (2) economic development accompanies more investment in human capital and lower fertility due to the quantity–quality trade-off, and (3) a current low level of fertility corresponds to very low support ratios for keeping up with frontier economies in the long run. Panel analysis for 178 countries shows that (1) and (2) are satisfied for Asia with higher elasticity than others. As for (3), we set up a dynamic model for simulations, showing that approximately two-third of Asia’s developing countries have an unsustainable level of support ratios, implying possibility of a middle-income trap due to future demographic headwinds.     

Implications of land use transitions on soil nitrogen in dynamic landscapes in Tanzania

Land use transitions are rated among the leading sources of greenhouse gas emissions in the tropics. They significantly challenge the functioning of ecosystems and affect multi-temporal stability of greenhouse gases such as N₂O and soil properties. Studies on dynamics in nitrogen balances are essential in understanding greenhouse gas emissions such as N₂O and to manage their impacts on productivity. In this study, multi-temporal Landsat images (1975, 1995 and 2012) were classified to determine land use transitions and potential drivers. The classified images were categorized into degraded and non-degraded lands and eighty sampling plots generated within the entire study area. Soil samples were then collected at 0–15, 15–30 and 30–60 cm depths on each plot and soil nitrogen determined. A regression analysis was developed to determine the influence of forest and grassland degradation on soil nitrogen. Results indicated a significant change in major land use and land cover types. Specifically, there was a decrease in areas covered by forests, woodland and grassland, however, area covered by less dense forest increased. Results also indicated variability in mean nitrogen content between degraded and non-degraded areas and depths. Furthermore, levels of degradation influence nitrogen content up to a soil depth of 30 cm. The present study is relevant in the detailed assessment of the extent of damage and threats posed to biodiversity hotspots in sub-Saharan Africa. These results are transferable to other parts of the world characterized by dynamic ecological transformation.     

Soil is brown gold in the Emilia-Romagna region,Italy

Soil is a natural resource essential to human welfare by virtue of its numerous crucial functions. In the past, soil has been taken for granted because of its widespread, albeit finite, availability. However, now that world's population is projected to exceed ten billion before the end of this century, soil is increasingly perceived as a precious commodity. Consequently, soil is increasingly under pressure by rich private investors and governments within the poorest countries to satisfy appetites for food production and biofuel. A case study is used to explore the plausibility of soil being considered as ‘brown gold’. Based on the comparison of land use maps, we estimated the value in terms of resource from raw material, carbon sink and virtual calories of the productive soil lost during the period 2003–2008 in the Emilia-Romagna Plain, one of the most productive areas of Italy. More than fifteen thousand hectares of cropland underwent land use change – in particular urbanization – over the 6-year period with an implied loss of crop production potential equivalent to the daily calorific requirement of more than 440,000 people. Taking into account that Italy is no longer self-sufficient in food production, such a loss appears to be strategically significant. Perhaps more importantly, urbanization and soil sealing has had negative ramifications on environmental sustainability, on both local and broad scales, with increased consumption of public funds. A logical framework of the socio-economic impact of land use change has been compiled and is presented as a possible example of a policy relevant approach to managing productive soils as a finite resource.     

A Population Projection for Indonesia, 2010–2035

In the context of its long-term planning, from time to time the Indonesian government publishes an official population projection. The latest projection was released on 29 January 2014. In this article, I describe and evaluate the methods and assumptions used to produce the projection, and provide key results.     

Demographic Transition and Fertility Rebound in Economic Development*

Recent evidence on the “fertility rebound” offers credence to the idea that, from the onset of early industrialization to the present day, the dynamics of fertility can be represented by an N-shaped curve. An overlapping generations model with parental investment in human capital can account for these observed movements in fertility rates during the different stages of demographic change. A demographic transition with declining fertility emerges at the intermediate stage, when parents engage on a child quantity–quality trade-off. At later stages, however, the process of economic growth generates sufficient resources so that households can rear more children while still providing the desirable amount of education investment per child.