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18 recordsLinked to original sources
PubMed1986

Agricultural change and population growth: a brief survey on the case of China in historical perspective.

A historical review of the relationship between agricultural change and population growth in China is presented. "This paper will try to discuss four aspects of agricultural change that are related to population growth. They are: (1) expansion of agricultural frontier, (2) changes in cultivation methods and land use, (3) improvements in agricultural technology, and (4) irrigation and water-control. Each of these aspects [is] treated briefly with temporal and spatial perspectives...." The relevance of the Boserup theory that population pressure leads to agricultural development is considered in the Chinese context. It is found that some evidence supports the theory. (summary in CHI)

Agriculture↗
PubMed1996

Induced intensification: agricultural change in Bangladesh with implications for Malthus and Boserup.

Bangladesh is dominated by a small-holder agrarian economy under extreme stress. Production shortfalls, increasing economic polarization, and chronic malnutrition are persistent, but major famine has been diverted in part by significant growth in agriculture. This recent history is open to both Malthusian and Boserupian interpretations-a history we explore here through a test of the induced intensification thesis of agricultural change. This thesis, framed by variations in the behavior of small-holders, has grown from a simple demand-production relationship to a consideration of the mediating influences on that relationship. The induced intensification thesis is reviewed and tested for 265 households in 6 villages in Bangladesh from 1950-1986. A time-series analysis of an induced intensification model provides relatively high levels of explained variance in cropping intensity (frequency and land productivity) and also indicates the relative impacts of household class, environment, and cropping strategies. On average, the small-holders in question kept pace with the demands on production, although important class and village variations were evident and the proportion of landless households increased. These results, coupled with evidence that agricultural growth involved intensification thresholds, provide clues about Malthusian and Boserupian interpretations of Bangladesh, and suggest that small-holder agriculture there is likely to continue on a "muted" path of growth.

Agriculture↗
PubMedDate not supplied

Population growth and distribution versus agricultural change: an analysis of the Warli tribal community in Dahanu and Talaseri Talukas of Thane district (Maharashtra).

The authors examine the relationship between population growth and agricultural change using a village-level study of the Warli tribal community in Maharashtra, India. "This paper tries to highlight the relationship that exists between the two factors and the relative changes in the structural character of the two factors. It also focuses on the complications brought about by the juxtaposition of a market economy of the nontribals on the subsistence peasant agriculture of the Warli tribals. Methodology is empirical. Suitable statistical aids have been used on available census material [for the years 1901-1971], substantiated with fieldwork."

Agriculture↗
PubMed2001

Modeled impacts of farming practices and structural agricultural changes on nitrogen fluxes in the Netherlands.

In the Netherlands, nutrient emissions from intensive animal husbandry have contributed to decreased species diversity in (semi) natural terrestrial and aquatic ecosystems, pollution of groundwater, and possibly global warming due to N2O emissions. This paper presents the results of a modelling study presenting the impacts of both structural measures and improved farming practices on major nitrogen (N) fluxes, including NH3 and N2O emission, uptake, leaching, and runoff, in the Netherlands, using input data for the year 2000. Average annual fluxes (Gg N year(-1)) for the year 2000 were estimated at 132 for NH3 emission (160 Gg NH 3 year(-1)), 28 for N2O emission, 50 for N inflow to groundwater, and 15 for N inflow to surface water at a total N input of 1046. At this input, nitrate (NO3) concentrations in groundwater often exceeded the target of 50 mg NO3 l(-1), specifically in well-drained sandy soils. The ammonia (NH3) emissions exceeded emission targets that were set to protect the biodiversity of nonagricultural land. Improved farming practices were calculated to lead to a significant reduction in NH3 emissions to the atmosphere and N leaching and runoff to groundwater and surface water, but these improvements were not enough to reach all the targets set for those fluxes. Only strong structural measures clearly improved the situation. The NH3 emission target of 30 Gg NH3 year(-1), suggested for the year 2030, could not be attained, however, unless pig and poultry farming is completely banned in the Netherlands and all cattle stay almost permanently in low emission stables.

Agriculture↗
PubMed2003

Loss of plant species richness and habitat connectivity in grasslands associated with agricultural change in Finland.

The drastic loss of seminatural grasslands and the decrease in species diversity in Europe during the 20th century are closely linked to social-economic factors. Development in agricultural production drives land-use changes, and thus controls the capacity of landscapes to maintain biodiversity. In this study, we link agricultural production changes to landscape fragmentation and species diversity. Our results show that the termination of grazing on seminatural grassland caused significant changes in landscape structure and a decline in the number of vascular plant species. The decline of grazed grasslands has been driven mainly by farm-level economic efficiency and profitability interests, which have been connected with agricultural policy measures. Since 1995, when Finland joined the European Union, the area of grazed patches in our study area has again increased as a result of a support scheme for the management of seminatural grasslands.

Agriculture↗
PubMed1995

Dietary shifts and implications for US agriculture.

Changes to healthier dietary patterns similar to those of traditional Mediterranean diets or those of the US government's dietary guidelines and food guide pyramid would require significant changes in American agricultural practices. The volume, mix, production, and marketing of agricultural commodities would need to be modified. Because differences between actual and recommended intakes for major food groups are quite large and affect a broad range of products, adjustments in supply and demand could overshadow past experience in dealing with such changes. New food and agriculture policies may well be needed to ease and accelerate agricultural adjustments, to improve nutritional characteristics of popular foods, and to promote desirable changes in consumers' food choices.

Agriculture↗
PubMed1983

Income and dietary adequacy in an agricultural community.

Although many studies as well as conventional wisdom suggest that increases in income result in improved diet and nutritional status in rural areas of developing countries, several recent studies have failed to demonstrate such a relationship. In this paper the relationships between material wealth and income and dietary strategies are examined for an agricultural community in rural Mexico. A superficial examination focusing on summary indices of dietary adequacy frequently cited in the literature and indices of wealth and income demonstrates a positive relationship between them in this community. However, an examination of the same data emphasizing alternative dietary strategies to achieve nutritional adequacy shows a more complex picture. Increasing income is associated with consumption of purchased foods especially foods of animal origin, and is not associated with the consumption of staple foods produced within the household. Diets dependent on purchased foods do not necessarily meet nutritional needs more adequately than diets which rely on agricultural products and gathered foods. Among the implications of this research are a need for a method of analysis which focuses on alternative nutritional strategies available in particular settings, and a need to reassess the relative importance of income generating activities and subsistence agriculture in areas undergoing agricultural change.

Agriculture↗
PubMed2005

Estimation and projection of nitrous oxide (N2O) emissions from anthropogenic sources in Taiwan.

Taiwan is a densely populated and developed country with more than 97% of energy consumption supplied by imported fuels. Greenhouse gas emissions are thus becoming significant environmental issues in the country. Using the Intergovernmental Panel on Climate Change (IPCC) recommended methodologies, anthropogenic emissions of nitrous oxide (N2O) in Taiwan during 2000-2003 were estimated to be around 41 thousand metric tons annually. About 87% of N2O emissions come from agriculture, 7% from the energy sector, 3% from industrial processes sector, 3% from waste sector. On the basis of N2O emissions in 2000, projections for the year 2010 show that emissions were estimated to decline by about 6% mainly due to agricultural changes in response to the entry of WTO in 2002. In contrast to projections for the year 2020, N2O emissions were projected to grow by about 17%. This is based on the reasonable scenario that a new adipic acid/nitric acid plant will be probably started after 2010.

Agriculture↗
PubMed1998

New emerging zoonoses: a challenge and an opportunity for the veterinary profession.

The concept of emerging infectious diseases appeared in the late 1980s, when major outbreaks occurred around the globe and surprised many scientists who considered infectious diseases to be maladies of the past or limited to the under-developed world. Several reports identified erosion of the public health infrastructure among the factors contributing to new and re-emerging infectious diseases. As indicated by Morse, "Disease emergence often follows ecological changes caused by human activities such as agriculture or agricultural change, migration, urbanization, deforestation, or dam building". "Among these new diseases, surprisingly, most emergent viruses and many emergent bacteria are zoonotic". Several new zoonoses have been recently identified. Many of these diseases were either unknown, because we were not able to isolate the infectious agent or to distinguish them from other clinical syndromes, or discovered accidentally. Much of the recent identification of new pathogens has been based on new molecular biology tools or epidemiological studies. For all these diseases or infections, veterinarians played a key role in their identification, isolation of the causative organisms and understanding of the epidemiology of the infection. The role of the veterinary profession is very important in public health and on the rise again in the U.S.A., as it should be in many other countries. Surveillance, clinical curiosity and awareness, epidemiology and laboratory training are the essential tools and competency that the veterinary profession must use to meet the challenge of new emerging zoonoses.

Animals↗
PubMedDate not supplied

[Evaluation of food consumption patterns and nutrition in 4 rural communities].

OBJECTIVE: To study the effect of agricultural change and subsequent social change on the nutritional situation of 4 communities of different regions and climates, that since the 70's have changed from traditional corn production to commercial sorghum production. MATERIAL AND METHODS: A new dietetic and clinical survey (1996) was performed to follow-up the changes in the 4 communities studied 12 years before (1984). RESULTS: The food consumption pattern continued changing, with more dietary diversification, better protein quality and less corn consumption. The child nutrition status on average was better. This happened in spite of the fact that the sorghum production was in a crisis and the communities partially returned to corn production, diversified production or migrated from the communities. CONCLUSIONS: In spite of first abandoning traditional corn production and later having problems with the commercial product (sorghum), the communities are still improving their nutrition. This is mostly due to implementing certain survival strategies, to receiving support from the people from the community who migrated and to a better food availability.

Crops, Agricultural↗
PubMed1988

African migration decision-making process.

Factors affecting the decision to migrate in Africa are reviewed. The author concludes that most migration studies have focused on the individual migrant, whereas migration decision-making in Africa is affected primarily by "the social institutions at local and household levels. Patterns of migration are influenced by the economic and social trends which developed especially since the colonial era." The importance of extended family relationships, agrarian change, forced migration, and restrictive migration policies indicate a need to take a macrolevel approach to the study of African migration.

Africa↗