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Agricultural biotechnology in an ethical context Texte intégral
1999
Todhunter, Ben
The New Zealand Kellogg Rural Leaders Programme develops emerging agribusiness leaders to help shape the future of New Zealand agribusiness and rural affairs. Lincoln University has been involved with this leaders programme since 1979 when it was launched with a grant from the Kellogg Foundation, USA. | The introduction of some agricultural biotechnologies in New Zealand has created considerable controversy. The main objections concern possible harm to man, damage to the environment and discomfit about the 'unnatural' status of the technology. This report has therefore examined the ethical issues that are raised by the development and application of food based biotechnologies. Three ethical principles have been used in that examination: 1) the principle of general human welfare 2) the maintenance of people's rights 3) the principle of justice. A framework using the three ethical principles has been advanced with the aim of reducing the controversy and leading to optimum outcomes.
Afficher plus [+] Moins [-]Colonisation of constructed wetlands in an agricultural landscape: Outline of an ongoing investigation
1999
Ekeberg, A.K. | Walseng, B.
Agricultural extension policy and practice in Australia: an overview
1999
Marsh, S.P. (Western Australia Univ., Nedlands, W.A. (Australia).) | Pannell, D.J.
Knowledge basis on corrosion prevention in an agricultural machine
1999
Kubera, J. | Tomczyk, W. (Akademia Rolnicza, Krakow (Poland))
Paper presents considerations regarding expert system model on corrosion prevention in an agricultural machine. Rules of knowledge basis were supplemented with the choice of consideration abstractionism included in the frames reflecting the hierarchical model
Afficher plus [+] Moins [-]Macrocharacterization of agricultural systems in West Africa: an overview
1999
Manyong, Victor M. | Smith, J. | Weber, G. | Jagtap, S.S. | Oyewole, B.
GIS analysis of change in an agricultural landscape in Central Finland Texte intégral
1999 | 2002 | 1996
Ruuska, Riitta | Helenius, Juha
GIS analysis of change in an agricultural landscape in Central Finland Texte intégral
1999 | 2002 | 1996
Ruuska, Riitta | Helenius, Juha
v | ok | Keskisuomalaisen maatalousmaiseman muutosten GIS-analyysi
Afficher plus [+] Moins [-]GIS analysis of change in an agricultural landscape in Central Finland
1996
Ruuska, Riitta | Helenius, Juha
Sources of phosphorus exported from an agricultural watershed in Pennsylvania Texte intégral
1999
Sharpley, A.N. | Gburek, W.J. | Folmar, G. | Pionke, H.B.
Freshwater eutrophication is usually controlled by inputs of phosphorus (P). As point source controls have decreased P inputs, the relative contributions of nonpoint inputs from agriculture have increased. Thus, remedial strategies are now being directed towards minimizing P export from agriculture. To identify critical sources of P, we investigated chemical and hydrologic factors controlling P export from a mixed land use (30% wooded, 40% cultivated, 30% pasture) 39.5 ha watershed in east-central Pennsylvania. The watershed was divided into four hydrologically distinct segments and streamflow and P concentration from each segment measured since June 1996. Mehlich-3 extractable soil P, determined on a 30-m grid over the watershed, ranged from 7 to 788 mg kg-1. Generally, soils in wooded areas had low Mehlich-3 P (<30 mg kg-1), grazed pasture had Mehlich-3 P values between 100 and 200 mg kg-1, and cropped fields receiving manure and fertilizer applications were in most cases above 200 mg kg-1. Average flow-weighted P concentrations for ten storms during August-November 1996 decreased 60% downstream from segments 4-1 (watershed outlet). Streamflow P concentrations were more closely related to the near-stream (within 60 m) than whole watershed distribution of high-P soils in each watershed segment. This suggests that near-stream surface runoff and soil P, control P export form the watershed. Thus, managing P application in the primary surface runoff-producing areas near the stream has a greater potential to decrease P export in streamflow than for areas further from the channel. Clearly, the integration of areas of high soil P with areas of surface runoff production must be considered when guidelines are developed for P applications. Considering the distribution of high P soils alone may unnecessarily restrict farm management options without providing the desired reduction in P export from watersheds.
Afficher plus [+] Moins [-]History and an analysis of agricultural journalism in the Philippines
1999
Revilla, R.DV.
Results of historical study pointed to the fact that the practice of popularized agricultural writing in the country started at Los Banos, specifically, at the old UPCA [University of the Philippines College of Agriculture]-Extension and Publications Office. Aside from two early Spanish agricultural publications, no records of early Agricultural Journalism practices have been found. As a specialized topic in the general practice of journalism, Agricultural Journalism did not merit mention in history books. In the second part of the study, content analysis showed that the three broadsheets (Bulletin, Inquirer and Star) allocated majority of their editorial space (61 percent) to text and heads. Also, majority of their space for agri-related pictures (74 percent) were allocated for photo releases. The three dailies, however, differed in their space allocation for advertisements. In terms of frequency, there were more straight news stories (49 percent) in the agricultural pages of the three national dailies studied. Agricultural stories were written mostly by staff writers (27 percent). Also compared to other story categories, the three newspapers studied allocated during a two-month period only 5 percent of the total stories to agriculture. The dailies published a considerable number of stories on economics (12 percent) and overseas or foreign news (11 percent). Results of the study further showed 60 existing agri-related publications in the country and two regular newspaper agricultural sections (Star and Bulletin). The last part of the study projected on Agricultural Journalism scenario ruled by computers, for faster gathering and delivery of agricultural stories
Afficher plus [+] Moins [-]Dispersal characteristics of seven odonate species in an agricultural landscape Texte intégral
1999
Conrad, K.F. | Willson, K.H. | Harvey, I.F. | Thomas, C.J. | Sherratt, T.N.
Dispersal is an ecological phenomenon which is of fundamental importance to population biology. While dispersal behaviour of many orders of winged insects has received a great deal of attention, the dispersal characteristics of odonates have been poorly documented. We used capture‐mark‐recapture techniques to study dispersal behaviour of seven species of odonates breeding on a network of 11 small ponds in Cheshire, U.K. The ponds ranged in size from 615 to 1300 m²‐ and varied from 30 to 860 m apart. We found surprisingly high rates of dispersal between ponds, with 10-47% per species of recaptured individuals moving from their natal pond. The mean probability of dispersal differed significantly among species but the relationship between the probability of dispersal and distance moved consistently followed a simple negative exponential curve for all species. Most individuals stayed at their natal pond, but a few moved long distances. Neither the age at which an individual was marked (teneral vs sexually mature) nor its sex significantly affected its tendency to disperse. The negative exponential relationship suggests that dispersal should be relatively easy to incorporate in more complex models of odonate spatio‐temporal dynamics. To our knowledge, this is the first large‐scale, multi‐species study to assess dispersal behaviour of odonates by direct observation.
Afficher plus [+] Moins [-]Sources of phosphorus exported from an agricultural watershed in Pennsylvania
1999
Sharpley, A.N. (Pasture Systems and Watershed Management Research Lab. USDA-ARS, University Park, PA (USA).) | Gburek, W.J. | Folmar, G. | Pionke, H.B.
