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111.
Three juvenile Brazilian sharpnose sharks (Rhizoprionodon lalandii) caught in gillnets in southeast Brazil, southwest Atlantic, were found with plastic debris rings around their gill or mouth region. The rings caused severe abrasion on the sharks' tissues as the animal grew, the collars probably hampering normal feeding and/or ventilation since two of the collared individuals were emaciated. The rings were identified as detachable lid parts from plastic bottles, likely thrown overboard by fishery and/or recreation boats. As several carcharhinid shark species dwells and reproduce in shallow waters, the impact of discarded plastic debris likely is greater on this shark type. 相似文献
112.
Chandna RC 《Population geography : a journal of the Association of Population Geographers of India》1989,11(1-2):77-85
Population policy and the 5-year plans since 1951 in India are reivewed and evaluated in terms of limiting population growth. The family planning (FP) programs have not had a major impact on people's attitudes, practice of contraceptives, or the average fertility rate. Not enough attention has been paid to the interaction of demographic structure and economic and social development, and the implications for limiting population growth. Vital elements of a population policy are containing population growth, limiting births among the young and reproductive age groups, enhancing employment options for males and females, diversifying the economy, improving literacy and educational standards, improving urban/rural ratios, and balancing male/female ratios. Several approaches to FP programs are possible: long term measures to improve the social, economic, and demographic structure, and short term measures to immediately avert births. Long term approaches recognize the complexity of the problem. Rapid socioeconomic development is the best contraceptive for controlling India's population. A well conceived population education program can help, as will increasing the marriage age, preventing children from entering the labor market, increasing female education levels, providing old age pension and social security and other insurance, and providing maternity benefits for small families. Short term measures may provide temporary or permanent methods of averting births; i.e., contraceptives, sterilization, penalties and rewards for small families. However, it must not be a bureaucratic measure imposed from above. It must be a self generating process. The author suggests that simultaneous long and short term approaches are necessary. Research should be conducted to delineate which measures have the most impact on reducing fertility and policy be formulated in accordance with these answers. Compulsion is required, and government should not hesitate to step in. In rural areas, traditional and modern methods in FP should be tried in order to achieve responsible behavior. The population increases in India were a result of a mortality decline starting in 1921 and a fertility decline starting in 1971. Attention must focus on high fertility areas such as Uttar Pradesh, Bihar, Madhya Pradesh, and Rajasthan. The 7th 5-year plan was important for making FP voluntary and generating an environment for fertility decline, and the 8th should establish FP as a self generating process. 相似文献
113.
Jones RC 《The Journal of geography》1984,83(2):58-64
An analysis of illegal migration between Mexico and Texas is presented using data from the U.S. Immigration and Naturalization Service's I-213 form on deportable aliens. Consideration is given to migrant characteristics and to origins of migrants in Mexico. 相似文献
114.
Chandna RC 《Population geography : a journal of the Association of Population Geographers of India》1996,18(1-2):9-26
This paper analyzes the prevailing demographic trends and development processes in India. Data were taken from the World Development Report and the Human Development Reports of South Asia and India, Census of India, and Government of India's Economic Survey. A much slower economic progress and human development was observed in South Asia as compared to those in East Asia. At present, the income levels in East Asia are 27 times higher and have a human development index twice that of South Asia. India had a better economic performance as compared to other countries in South Asia. However, the human deprivations within India continue to hinder the country's emergence as a politico-economic power on the international scene. Investigation of the diversity in population growth and development in India was presented in this paper using indicators such as: average annual population growth; couple protection rate; female literacy; mean age at marriage for females; infrastructural facilities; proportion below poverty line; and the per capita income. Finally, specific suggestions on how to accelerate the fertility transition in the country were enumerated. 相似文献
115.
Taragi RC Kumar K 《Population geography : a journal of the Association of Population Geographers of India》1991,13(1-2):23-30
"The present endeavour has an emphasis on analysing distributional patterns of some...population characteristics [in India] as a case perceived at the physiographic-regional level, that is to say, the variability of population characteristics over different natural environments as well as within a similar physical entity. Specifically it aims at analysing the pattern of population density, growth, urbanisation level and literacy varying from one physiographic region to [another] and the relationship of these four variables with each other at the same level of regional structure." 相似文献
116.
117.
加利福尼亚近海圣巴巴拉盆地沉积通量与纹泥的形成关系RobertC.Thunel等我们对过去气候变化特征的了解部分地建立在对各种地质记录反映出的各种短暂沉积作用的分析上面(Baumgartner等,1989),通常在海洋环境中,低的沉积物堆积速率和底栖... 相似文献
118.
Kaur S Chandna RC 《Population geography : a journal of the Association of Population Geographers of India》1983,5(1-2):87-104
The post-Independence period in India has witnessed a gradual decline of some occupations and services and the emergence of others. In the present paper an attempt has been made to analyze the change in the industrial structure of India's male working force by calculating an index of change. The index so calculated for 2 decades separately (1961-1971 and 1971-1981) is portrayed cartographically. The overall low degree of change recorded by the country's male working force establishes the weakness of India's industrial infrastructure. Consequently, the secondary sector seems to have failed in generating employment opportunities on a large scale. Regionally, the peripheral areas have recorded a higher incidence of change than the interior heartland of the country. The areas that were overwhelmingly agricultural and had experienced developments in the field of agriculture alone exhibited a low degree of change in comparison to those that had experienced developments both in the field of agriculture and industry. During the last inter-censal period (1971-1981) the country recorded an accelerated rate of change in the industrial structure of its male working force. Spatially too, the increasing rate of change has spread to new regions. 相似文献
119.
120.