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1.
Chandna RC Sharma D 《Population geography : a journal of the Association of Population Geographers of India》1987,9(1-2):45-55
Using a sample of 885 females (1/2 of all married women of reproductive age), this study examines the role of education as a determinant of fertility among couples in Kullu town of Himachol Pradesh, India. Of the 885 respondents, only 149 were illiterate. The average family size was 2.88. Findings reveal that 1) the average family size was largest for illiterate respondents (3.57) and for illiterate males (3.76); 2) average family size declined consistently after the middle level of education to 1.29 for post graduate respondents and 2.33 for post graduate males; 3) a negative correlation exists between fertility and education of both husband and wife, with the wife's education having a stronger negative correlation with fertility; and 4) couples with an educational level of matriculation and above have a distinctly smaller family size than those less educated. 相似文献
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Kumar K Taragi RC 《Population geography : a journal of the Association of Population Geographers of India》1986,8(1-2):58-63
There are great spatial variations in the distribution of the fast growing populations of India. About 70% of the 1981 population is concentrated in only 40% of the geographical area. Such a pattern of population concentration, with its spatio-temporal dimension, can be understood better if examined at the macro-regional level considering the physico-climatic and socio-economic diversity of the country. This is done by way of analyzing district level data for India as a whole and also for its various macro-regions. The study reveals that the Great Plains and Coastal Plains and Islands have a homogenous distribution and a higher population increase. The Deccan Plateau shows the most homogenous dispersion of population. The population is declining in the Northern Mountains and the Great Plains but accentuating in the Coastal Plains and Islands and the Deccan Plateau. The north and south of India are showing opposite trends in population concentration. 相似文献
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Chandna RC 《Population geography : a journal of the Association of Population Geographers of India》1991,13(1-2):1-6
The field of population geography was first introduced during the 1960s in India and advanced under the direction of Gosal at the Punjab University. Teaching and research in population geography were introduced by Chandigarh at Punjab University, which today is the main center of research activity. Population geography in India has followed the main tenets of geography in general and is based on spatial perspectives. Deficits are apparent in the paucity of research on socioeconomic implications of spatial distributions, but there is infrastructural feedback to support theory development. Theoretical advances moving from theory to fact or from empirical fact to theory are limited. Comprehensive training in methodology and quantitative techniques is needed for further development of population theory: multivariate analysis, factor analysis, principal component analysis, model building, hypothesis testing, and theory formulation. Methodological sophistication will also help in understanding and interpreting the diverse and complex Indian demographic situation. The analysis of population geography in the Indian spatial, cultural, political, and historical context may be applied to other less developed countries of similar sociocultural background. The Indian Census has contributed over the 100 years of its existence reliable and efficiently produced data on a wide variety of measures at assorted scales down to the village level. Field work among geographers has not achieved a level of development commensurate with population censuses. Recent doctoral research has focused on qualitative studies of local situations. Research topics range from the distribution and structure of population, mortality, fertility, and migration to peripheral issues of social segregation. Popular topics include urbanization, labor force, sex composition, literacy, and population growth. Distribution of population and density studies have amounted to only 2 in 30 years. Population texts are in abundance. The Punjab University is the headquarters of the Association of Population Geographers, which publishes the journal "Population Geography." Many advances are still needed in a timely fashion. 相似文献
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Predicting copper toxicity in estuarine and marine waters using the Biotic Ligand Model 总被引:6,自引:0,他引:6
The Biotic Ligand Model (BLM) has proven efficient in predicting the toxicity of a variety of metals to freshwater organisms. Consequently, the US EPA has proposed its use for calculating freshwater copper criteria. This study evaluates the BLM for use in estuarine and marine waters. Studies were conducted using the bivalve, Mytilus sp. and 48-h embryo-larval development chronic estimator test methods. These are the most sensitive taxa and test in the US EPA saltwater copper criteria database. Samples from five locations around the USA were tested. There is a strong relationship between measured and BLM predicted copper EC50s (log transformed data, r2 = 0.76, p < 0.001, n = 44). The BLM predicted within a factor ±2 of measured EC50s in 41 of 44 cases. However, the BLM tends to predict lower EC50s when measured EC50s are approximately 10 μg Cu/L. This may be due to limitations of the metal-dissolved organic matter interaction model. 相似文献
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