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1.
Unprecedented population growth and migration accompanied equally unprecedented land use and land cover change in Latin America during the latter decades of the twentieth century. Country-level data are examined with bivariate statistics to determine relationships between changes in population patterns and land use (agriculture and forest cover) from 1961 to 2001. In South America, large forest areas were eliminated during the period, while exceptionally high rates of forest clearing were ubiquitous in the Central America/Caribbean region. These environmental changes accompanied dissimilar initial population densities and different effects of population change on agriculture. While interacting with a host of political, socio-economic, and geographic processes, it appears that both Malthusian and Boserupian demographic processes were important drivers of deforestation. Given continued, though slowing, population growth, increased urban consumption, and future land use constraints, policy makers face myriad challenges in advancing sustainable agriculture-population dynamics in Latin America.  相似文献   

2.
During the last two decades of the twentieth century, Italy, Greece, Spain, Portugal, and Japan were characterized by very low fertility levels and limited diffusion of the pill, IUD and sterilization for contraceptive purposes. This paradox is discussed for Italy by revisiting the history of contraception and reproduction during the second half of the twentieth century, and by using new data for the end of that century and the early twenty-first century. The main results are: (1) it has been possible to maintain low rates of planned and unplanned fertility without resorting to more effective contraceptive methods thanks to a careful use ofcoitus interruptus; (2) the pace of diffusion of the pill and IUD was so slow because of the opposition to contraception of the Catholic Church, a gender system emphasizing traditional male and female roles, and a medical culture that made physicians reluctant to prescribe the pill for their patients; and (3) the contraceptive patterns of Italian women born after 1960 are more similar to those of their Western counterparts, although new peculiarities appear, for example, substantial reliance on the condom by people living as couples as well as sexually active singles.  相似文献   

3.
Smith DW  Bradshaw BS 《Demography》2006,43(4):647-657
The National Center for Health Statistics (NCHS) reports life expectancy at birth (LE) for each year in the United States. Censal year estimates of LE use complete life tables. From 1900 through 1947, LEs for intercensal years were interpolated from decennial life tables and annual crude death rates. Since 1948, estimates have been computed from annual life tables. A substantial drop in variation in LE occurred in the 1940s. To evaluate these methods and examine variation without artifacts of different methods, we estimated a consistent series of both annual abridged life tables and LEs from official NCHS age-specific death rates and also LEs using the interpolation method for 1900-1998. Interpolated LEs are several times as variable as life table estimates, about 2 times as variable before 1940 and about 6.5 times as variable after 1950. Estimates of LE from annual life tables are better measures than those based on the mixed methods detailed in NCHS reports. Estimates from life tables show that the impact of the 1918 influenza pandemic on LE was much smaller than indicated by official statistics. We conclude that NCHS should report official estimates of intercensal LE for 1900-1948 computed from life tables in place of the existing LEs that were computed by interpolation.  相似文献   

4.
The share of the elderly living with an adult child decreased monotonically throughout the twentieth century, while the probability of reaching old age and the number of years lived in old age increased. As a result, the expected number of life-years lived with adult children while in old age may have increased, decreased, or stayed the same. I estimate that the number of life-years lived in old-age coresidence with adult children stayed roughly constant between 1900 and 1940, while the rate of coresidence declined. Life years lived in old-age coresidence then declined substantially between 1940 and 1990. Moreover, the number of life-years lived in old-age coresidence in 1990 would have been roughly half as great as it actually was had there been no improvements in mortality between 1900 and 1990. And if fertility had remained at its 1900 levels, life-years lived in old-age coresidence would have been about 45% higher in 1990 than it actually was. The results imply that analyses of the change in familial assistance to the elderly should also consider changes in mortality.  相似文献   

5.
Population Research and Policy Review - Concerns over the prospects of explosive demographic growth led to concerted efforts to engineer fertility reductions in the developing world, while skeptics...  相似文献   

6.
7.
The increase in the Neolithic human population following the development of agriculture has been assumed to result from improvements in health and nutrition. Recent research demonstrates that this assumption is incorrect. With the development of sedentism and the intensification of agriculture, there is an increase in infectious disease and nutritional deficiencies particularly affecting infants and children.Declining health probably increased mortality among infants, children and oldest adults. However, the productive and reproductive core would have been able to respond to this increase in mortality by reducing birth spacing. That is, agricultural populations increased in size, despite higher mortality, because intervals between births became shorter.  相似文献   

8.
The study examines whether the income opportunities of Native Americans over the 1980s improved in response to stronger aggregate job growth or deteriorated in response to declining wage and employment opportunities, particularly for the less-skilled. Using data from the 1980 and 1990 US Census on individuals aged 16–64, a methodology is presented to analyze the effect of changes in the income distributions of Native Americans and whites on the average Native American-white income ratio. Oaxaca-type decompositions are also used to yield insights into the role of economy-wide as opposed to Native American-specific effects on changes in income, hourly earnings and annual hours employed over the period. The study concludes that the economic circumstances of Native American men and women further deteriorated relative to whites over the decade, chiefly due to the declining valuation given to Native American human capital, particularly for men. An important finding of the study is the role of economy-wide vis-à-vis native-specific effects: almost all of the adverse movements in average hourly earnings against Native Americans can be attributed to changes in economy-wide hourly earnings structures (with the least-skilled being paid less), whereas the large fall in relative annual hours is due to changes specific to Native Americans.  相似文献   

9.
Abstract In the Netherlands, as in other countries, substantial regional differences in the birth rate have always been the rule rather than the exception. Of course, differences in crude birth rates may be attributed to a number of possible reasons, not all of them of primary demographic interest. For instance, according to the census of 31st December 1899, the number of women per 1,000 men in the province of Drenthe was only 924; in the province of Zuidholland the corresponding number was 1,073. It is clear that, ceteris paribus, the crude birth rate in Zuidholland would be about 7% higher than in Drenthe at that time. In such a case, the difference could reflect differences in economic development or job opportunities, factors not devoid of demographic significance, but only indirectly so.  相似文献   

10.
Kiser CV 《Demography》1967,4(1):388-396
This is a review focused mainly upon the book Fertility and Family Planning in the United States, by Pascal K. Whelpton, Arthur A. Campbell, and John E. Patterson, published by Princeton University Press in 1966, and representing the results of the second GAF survey (1960). The initial GAF survey was conducted in 1955 and resulted in the book Family Planning, Sterility, and Population Growth, by Ronald Freedman, Pascal K. Whelpton, and Arthur A. Campbell, published by McGraw-Hill in 1958.A basic purpose of the GAF studies, as contrived by Whelpton, was that of trying to improve the bases for population estimates by learning from young women themselves the number of children that they expected to have altogether and during the next five years. By repeating the study five years later, it was hoped to test the validity of replies on expectations by comparing them with subsequent performance. This involved interviewing not the same women but the same types of women in 1955 and 1960.The GAF studies have indicated the usefulness of questions on number of children expected. They suggest that the replies of 1955 have low predictive value for individual behavior but high predictive value for group behavior. They have provided invaluable data on other aspects of fertility unavailable from official sources, such as family planning, fecundity, and the influence of religion. The chief inadequacies of the GAF studies have been those associated with small numbers. Moreover, definitive comparisons of expectations with performance would seem to require longitudinal studies of the same women rather than periodic studies of the same types of women. On the other hand, the latter type of design doubtless is preferable for other purposes.Besides the yield of new data on fertility, the GAF studies have been significant in that one government agency provided the funds for the National Fertility Survey of 1965, which was essentially a third round of the GAF studies, and another government agency is considering the institution of regular surveys of the GAF type in order to provide a wider scope of data relating to fertility. The volume under review is at once a fitting living memorial to the senior author and the Scripps Foundation, a credit to the coauthors, and a worthy model for future studies.  相似文献   

11.
This paper reviews half a century of research into the determinants of fertility. It is argued that the quest for the determinants of fertility behaviour and change during that period can best be interpreted as the development of a series of sub-narratives from different disciplinary perspectives and orientations. These are normally based upon the initial narrative of the demographic transition and usually take the form of a verbal theory illustrated by a 'box and arrow' diagram. On occasions formalization has been attempted. Different parts of the initial narrative have been highlighted at different times depending on policy interest, improvements in technical skills, availability of data, changes in social setting, and the degree of satisfaction with the dominant sub-narrative of the day. There is every reason to believe that the research process identified will continue and will lead to a further accumulation of knowledge. In fact, all important variables have probably already been identified. That it will, ultimately, lead to a single, consolidated narrative fully satisfactory for all settings and for all time is, however, highly unlikely.  相似文献   

12.
Abstract. Influences on the fertility of men during the American fertility decline are examined using a sample of about 1700 married men born between 1830 and 1880, all of whom attended Amherst College, Massachusetts. We consider two types of reduced fertility: involuntary childlessness as a function of health in early adulthood, and voluntary fertility control as a function of access to contraceptive technology. The relation between health, as measured by body mass index, and childlessness was nonlinear, with average sized men significantly more likely ever to father children than thin or bulky men. Among men who ever fathered a child, physicians fathered significantly fewer children while having probabilities of childlessness that were statistically indistinguishable from those of other men. Physicians may have had greater access to relatively new contraceptive technologies, which suggests a role for voluntary fertility control.  相似文献   

13.
The data for race and ethnicity published from the 1980 Census are based on racial and ethnic self-identification of respondents. Selfidentification of race and ethnicity is problematic mainly because analysts are frequently inclined to treat this information as immutable. However, as this paper suggests, for some groups such as American Indians, racial and ethnic identity is an extremely complex phenomenon which has the potential to be highly variable. American Indians present an ideal case to demonstrate the possible problems facing analysts who do not recognize the potentially variable meanings of race and ethnicity data. This paper shows that, depending on how American Indians are defined, population estimates can range from less than 1.0 million to nearly 7.0 million. Furthermore, it is possible to isolate three types of American Indian identities in 1980 Census data, and each of these groups have different socioeconomic profiles.  相似文献   

14.
15.
Some of the special circumstances and issues involved in both the causes and treatments of sexual problems among gay men are discussed. Reported frequencies of specific dysfunctions are discussed, and desire, arousal, and orgasmic phases are used to describe the special problems gay men have. These categories are also used to explore some of the probable contributing factors and specific treatment issues and suggestions that have been found useful. Since there is some indication that inhibited ejaculation is a somewhat frequent problem among gay men and has been more difficult than some dysfunctions to treat, emphasis has been placed on possible causes and treatments that have been helpful. A category of sexually inexperienced gay men is also discussed.  相似文献   

16.
We estimate the extinction probability of a large and decreasing population, the southern bluefin tuna. This tuna was listed as critically endangered by the World Conservation Union (IUCN) in 1996. However, the absolute population size is still large and the extinction probability within the next half century is negligible if the recent population decline rate does not increase in the future. IUCN’s criterion with respect to the population decline rate should be linked to the absolute population size, if this is estimated. Several methods estimating the probability of extinction conclude that the southern bluefin tuna population will be below 500 mature individuals within the next 100 years and may be listed as vulnerable. These analyses suggest that extinction risk assessment is useful for management action for taxa that still have large population and are rapidly decreasing.  相似文献   

17.
Eblen JE 《Demography》1974,11(2):301-319
The difficulties of obtaining credible estimates of vital rates for the black population throughout the entire nineteenth century are overcome in this study. The methodology employed the notion of deviating networks of mortality rates for each general mortality level, which was taken from the United Nations studyThe Concept of a Stable Population. Period life tables and vital rates for intercensal periods were generated from the new estimates of the black population at each census date. The results of this study are highly compatible both with the life tables for the death-registration states in the twentieth century and the recent Coale and Rives reconstruction for the period from 1880 to 1970 and with several estimates of vital rates previously made for the mid-nineteenth century. This study places the mean life expectancy at birth for the black population during the nineteenth century at about 33.7 years for both sexes. The infant death rate (1000m (0)) is shown to have varied between 222 and 237 for females and between 266 and 278 for males. The intrinsic crude death rate centered on 30.4 per thousand during the century, while the birth rate declined from 53.2 early in the century to about 43.8 at the end.  相似文献   

18.
Past research has found that a stronger secure attachment style, developed in childhood, enhances one's ability to acknowledge negative feelings, cope with negative life events, and develop satisfying social relationships. Because an integral part of the "coming out" process for gay men is the ability to seek support from the gay community in order to reevaluate negative beliefs toward homosexuality, a gay man's attachment style may strongly impact this critical stage of his life. Results demonstrated that men who more strongly endorsed a secure attachment style reported more positive attitudes toward their own homosexuality, and that these more positive attitudes could mediate the relation between more secure attachment style, greater levels of self-disclosure regarding their homosexuality, and greater self-esteem. Implications of these data for internalized homophobia, the coming-out process, and effective social functioning are discussed.  相似文献   

19.
This symposium takes as its point of departure two books by Massimo Livi Bacci, Conquest and El Dorado in the Marshes, published in English in 2008 and 2010. Livi Bacci assesses widely varying estimates of the demographic dimensions of the collapse of the Native populations following their contact with Europeans and elucidates the proximate causes of that catastrophe. Drawing on models that combine production potential with demography, environment, and technology, Shripad Tuljapurkar discusses analogous historical experiences of the populations of Polynesia and the social transformation they entailed. David S. Reher argues that explanations of the estimated demographic dynamics need to take into account the negative fertility responses of the Indigenous population to the disruption of their traditional way of life. Focusing on the biological aspects of immunity to diseases such as smallpox, Andrew Noymer demonstrates that infectious diseases alone could not account for the Indios' population collapse. The contributions to this symposium are based on presentations at a session at the 2010 annual meeting of the Population Association of America, held in Dallas, Texas, that examined the demographic consequences of the Spanish conquest of the Caribbean region and of South America in light of the two books.  相似文献   

20.
Aassve A 《Demography》2003,40(1):105-126
This paper extends previous work on premarital childbearing by modeling both the entry rates and the exit rates of unwed motherhood among young American women. In particular, I investigate the impact of economic resources on the likelihood of experiencing a premarital birth and then of subsequent marriage. Using a multiple-destination, multiple-spell hazard regression model and a microsimulation analysis, I analyze the accumulating effects of various economic variables. The results show that the economic resources are indeed important both for premarital childbearing and for subsequent marriage. However, the simulations show that large changes in these economic variables do not necessarily translate into large changes in nonmarital childbearing.  相似文献   

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