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The strategies for reducing population growth include social development and improvement in the educational attainment of women. The decline in Kenya's growth rate was attributed to high female literacy and reduced infant mortality. Another strategy for enhancing fertility decline is to reduce child mortality, particularly from preventable causes such as diarrhea. The entire cost of such a strategy to reduce preventable disease would be about $1.33 per 300 million taxpayers in developed countries. Family planning services must be expanded. Prevention of maternal mortality and AIDS would bring major benefits. Strategies for environmental protection emphasized the already existing plan of action set out in the UNCED document Agenda 21 in Rio de Janeiro. The plan has suffered from inaction. The estimated cost of $625 million was considered to be several times smaller than the costs of inaction. The elimination of subsidies in tropical forests would have an immediate impact. Natural resource accounting at the national level would include the value of natural resources. Pricing would change radically for gasoline if the costs of urban smog, acid rain, low-level ozone pollution, and global warming were taken into account. Strategies for sustainable development pertained to the preceding strategies and others indicated in the Agenda 21 Action Plan. If funding were better targeted to the poorest 20% of global population with high fertility rates, the accomplishments would be heralded. 1.2 million are living in absolute poverty, and aid for nutrition, primary health care, water and sanitation, basic education, and family planning amounts to only 10% of expenditures. An increase to 20% would mean a contribution from Americans of $7.50 per person or 33% of $25 thousand million from all developed countries. Developing countries need to lower their military expenditures, privatize public enterprises, change inappropriate development policies, eliminate corruption, and improve national governance. The debt burden should be reduced.  相似文献   
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Eggshell quality, clutch size, sex ratio, and hatching success of western bluebirds (Sialia mexicana) and ash-throated flycatchers (Myiarchus cinerascens) were studied on a landscape-soil contaminant gradient at Los Alamos National Laboratory (LANL) in New Mexico from 1997 to 1999. A variety of contaminants (heavy metals, chemicals, insecticides, polychlorinated biphenyls (PCBs), organochlorines, and radioactive isotopes) range across different spatial scales and concentrations on LANL land. This study is an example of a monitoring program over a large area with varying degree of contamination that is used to highlight locations of concern for future research. There were two locations where the flycatcher had a lower hatching success. The bluebirds at Sandia wetland, a location of concern for PCBs. had a thinner eggshell thickness index (RATCLIFFE) and the eggs were smaller than at other locations. The flycatcher had thinner eggshells than bluebirds, which could add to sensitivity to exposure to contaminants. There was no variation in clutch size or sex ratio between locations or areas closer to contaminant release sites for both species. Percent females in the clutch ranged from 0 to 100% in the WEBL and from 33 to 67% for ATFL.  相似文献   
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The Atlantic Slope Consortium (ASC) is a project designed to develop and test a set of indicators in coastal systems that are ecologically appropriate, economically reasonable, and relevant to society. The suite of indicators will produce integrated assessments of the condition, health and sustainability of aquatic ecosystems based on ecological and socioeconomic information compiled at the scale of estuarine segments and small watersheds. The research mandate of the ASC project is the following:
Using a universe of watersheds, covering a range of social choices, we ask two questions:
  • ? How “good” can the environment be, given those social choices?
  • ? What is the intellectual model of condition within those choices, i.e., what are the causes of condition and what are the steps for improvement?
As a basis for compiling ecological indicators, a watershed classification system was required for the experimental design. The goal was to develop approximately five categories of watersheds for each physiographic province, utilizing landscape and land use parameters that would be predictive of aquatic resource condition. All 14-digit Hydrologic Unit Code (HUC) watersheds in the Mid-Atlantic region would then be classified according to the regime. Five parameters were utilized for the classification: three land cover categories, consisting of forested, agricultural, and urban, median slope or median elevation, and total variance of land covers in 1-km-radius circles positioned on all stream convergence points in a specified 14-digit?HUC watershed. Cluster analysis utilizing these five parameters resulted in approximately five well-defined watershed classes per physiographic province. The distribution of all watersheds in the Mid-Atlantic region across these categories provides a unique report on the probable condition of watersheds in the region.  相似文献   
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Summary In rhesus monkey populations, animals related by descent to some female comprise a matriline or genealogy. Data on blood protein polymorphisms in the Cayo Santiago rhesus colony indicate that allele frequency variations among matrilines in social groups are large. These variations occur despite high levels of outbreeding. Computer simulation analyses indicate that pedigree or linear effect account for much of the observed genetic differentiation among genealogies. A sampling with correlation model in which genealogy sizes and average kinship levels are parameters predicts among matriline genetic differentiation. This study indicates that substantial genetic substructure is present within rhesus social groups. Our analyses also predict that large variances in allele frequencies should be common among social or trait groups based on kinship relationships.  相似文献   
68.
There are important linkages between the health of humans and theenvironment, restoration of degraded lands, and long-term stewardship of public lands, yet most environmental indicators deal only with assessing the physical and biological aspects ofecosystems. In this article, we examine the ratings of perceptionsof several environmental problems for their utility as indicatorsof environmental quality, and examine perceptions of future land use by people interviewed in Santa Fe, New Mexico, near the Department of Energy's (DOE) Los Alamos National Laboratory (LANL). Overall, people with lower incomes rated environmental problems as more severe than others, were more willing to spend federal funds to solve them, and were consistent in their ratingsof severity of environmental problems and their willingness to spend federal funds. Cleaning up LANL and other Department of Energy sites, received the highest rating for expenditure of federal funds. The highest rated future uses for DOE sites were for recreation and for National Environmental Research Parks. People with less education generally gave higher ratings to mostfuture land uses for DOE than did those with more education. However, those with higher education gave higher ratings to nuclear reprocessing, and nuclear material storage. Where there were differences, the people interviewed at Santa Fe rated all environmental problems (except pesticides) as more severe than did those previously interviewed in Albuquerque (located fartherfrom the LANL site), and they were more willing to spend federalfunds on these problems. Ratings for all future land uses did notdiffer between the Santa Fe and Albuquerque respondents. These perception-based indicators show general agreement among peopleliving close and farther away from LANL with respect to cleaningup LANL and the future land uses for the site. These indicators should be considered by regulators, site personnel, and policy makers in future management and land use decisions.  相似文献   
69.
Fish and shellfish are exposed to a wide range of polycyclic aromatic hydrocarbons (PAH) following oil spills at sea, and can become contaminated as a result. Finfish have a more effective mixed-function oxidase enzyme system than shellfish, and are therefore able to metabolise and excrete PAH more effectively than the invertebrates. Thus, contamination by high-molecular weight PAH, including those with carcinogenic potential and so of concern with regard to human consumers, is therefore usually observed in shellfish, and particularly in bivalve molluscs. Oil spills are not the sole source of PAH, however, as parent compounds are also generated by a wide range of combustion processes. In this paper, consideration is given to monitoring data gathered following recent oil spills (both of crude oil and diesel fuel), alongside data from other studies. These include studies conducted around a former gasworks site and downstream of an aluminium smelter in the UK, and from mussel monitoring studies undertaken in the UK and the USA (including the Exxon Valdez oil spill and the National Status and Trends programme), and in other countries in Europe. For comparative purposes the PAH concentrations are summed and also expressed as benzo[a]pyrene equivalents, their relative concentrations being weighted in relation to the carcinogenic potential of individual PAH compounds using toxic equivalency factors (TEF). Our aim was to assess the utility of this approach in fishery resource monitoring and control following oil spills. Certainly this approach seems useful from the data assessed in this study. and the relative ranking of the various studies seems to reflect the relative degree of concern for human consumers due to the differing contamination sources. As a simple tool for control purposes it is equally applicable to PAH derived from oil spills, and from industrial and combustion sources.  相似文献   
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