摘要:

The European landscape reflects many centuries of dynamic interaction between people and their natural environments. Indeed, much of the current biological and aesthetic value of the wide variety of "cultural" landscapes has been created and is now maintained by long-established farming systems. Such traditional systems (many of which are pastoral based) are generally well integrated with the environment and involve management practices that do not over-exploit the natural carrying capacity of the land. However, the rapid modernisation of agriculture that occurred after the 1939-1945 war resulted in an intensification of many European farming systems and has had severe negative effects on the environment. This modernisation initially occurred primarily in northwest Europe fuelled by the European Union (EU) Common Agricultural Policy (CAP), but with the expansion of the EU it is continuing and is certain to increase in southern, central, and eastern Europe. The response of the EU to this fundamental imbalance between farming and the environment has included the introduction of compulsory regulations to ensure the implementation of minimum environmental standards in the production processes and the promotion of agri-environment programmes to encourage farmers to undertake positive environmental management on their farmland. The ongoing reforms of the CAP will undoubtedly place greater emphasis on agri-environment programmes and increasingly on the concept of "integrated rural development." There is, however, still a pressing need for detailed information to justify to the EU and world markets why certain types of farming system should be central to future European rural development policies.Key words: biodiversity, wildlife value, farming systems, European policy, agri-environment.

ISSN:1208-6053    

DOI:10.1139/a00-009

出版商:NRC Research Press    

年代:2000

数据来源: NRC

摘要:

Our dependence on electricity and our growing dependence on wireless telecommunication technology is causing this planet to be inundated with electromagnetic energy ranging in frequency from less than 60 Hz to greater than 2 GHz. Concerns expressed by the public, who live near power lines, cell phone antennas, or television and radio broadcast towers, have prompted two major reviews: one by the US National Research Council (NRC) and the other by the US National Institute of Environmental Health Science (NIEHS). Both of these documents deal with the biological and health effects primarily in a residential setting of extremely low frequency (ELF) or power frequency (50 and 60 Hz) fields. This paper critically evaluates the NRC and NIEHS documents. This evaluation includes both the content and the process leading to the final reports. It summarizes the information available on human exposure to electric and magnetic fields and identifies key biological markers and potential mechanisms that have been linked to electromagnetic exposure. It examines the conclusions of both documents in terms of the slightly broader realm associated with occupational exposure, non-power frequency fields, EMF hypersensitivity, and response of species other than humans. It presents some of the scientific controversy surrounding the question "Are low frequency electric and magnetic fields harmful?'' and examines the concepts of bias and consistency in data interpretation. This paper also attempts to place the discussions about technologically generated fields (technofields) into a much broader perspective, a perspective that includes naturally occurring geofields and biofields.Key words: leukemia, breast cancer, melatonin, calcium flux, extremely low frequency electromagnetic fields, radio frequency radiation.

ISSN:1208-6053    

DOI:10.1139/a00-004

出版商:NRC Research Press    

年代:2000

数据来源: NRC