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641.
This paper examines opportunities to improve the environmental and economic performance of cropping systems through intensified
application of information in agrichemical management. Through intensified application of information, both net farm income
and environmental quality may increase through more closely matching the specific needs of the crop with the type, timing,
and volume of chemical inputs used in crop production.
This study examines the current status and future prospect of agrichemical dealers offering information intensive agrichemical
management services to producers.
Agrichemical dealers are the focus of this study because: (1) farmers are perceived as ill-prepared to substantially upgrade
the sophistication of their agrichemical management without off-farm support, and (2) dealers enjoy a close relationship with
farmers, which potentially could be expanded to include a variety of information-based services. A mail survey was conducted
of all agrichemical suppliers/applications in Wisconsin. The response rate was 76% (172 of 225).
Substantial numbers of services were found to be offered by many dealers. The majority of these services were related to traditional
yield-enhancement function. Services that have a greater potential to mitigate the negative environmental impacts of inefficient
agrichemical use and have higher on-farm data requirements were found to be less widely offered by dealers. Analysis of constraints
to further development of information-intensive services indicates that dealers offering significant numbers of services are
concerned with constraints external to the dealership, while dealers offering relatively few services perceive internal constraints
as most limiting. This relationship indicates that efforts to accelerate dealerships' development of information-intensive
agrichemical management services should focus on specific constraints operating on targeted dealerships. 相似文献
642.
Aaron T. Wolf 《Journal of the American Water Resources Association》1995,31(6):1009-1022
ABSTRACT: This paper examines the relationship between best-management practices, institutional needs, and improved water quality within the watersheds of Wisconsin's program for controlling rural nonpoint source pollution. The first section describes the federal requirements for state nonpoint source programs and the legislative and management methods the state of Wisconsin uses to put those requirements into practice. The emphasis of the paper, described in the second section, is the institutional difficulty in evaluating the success of a large, integrated water quality program. Measurements which are investigated include (1) watershed water quality before and after implementation of BMPs; (2) program participation as measured by eligible vs. participating landowners, BMPs considered necessary vs. BMPs implemented, or dollars allocated to the NPS program vs. dollars expended; and (3) institutional goal coordination and management effectiveness. It is found that, despite the size and sophistication of Wisconsin's NPS program, there is little if any improvement in ambient water quality in these watersheds, probably because of a general lack of adequate participation in this voluntary program. 相似文献
643.
I. Anna S. Olsson Christian Gamborg Peter Sandøe 《Journal of Agricultural and Environmental Ethics》2006,19(1):37-46
Animal welfare and the ethical issues it raises have been discussed intensively for a couple of decades. The emphasis has
been on the direct effects of housing and husbandry, but more attention is now being given to problems originating in selective
breeding. European attempts to adjust animal welfare legislation to deal with these problems have been largely unsuccessful,
but the fact that selective breeding can introduce welfare problems continues to place an ethical responsibility on the animal
breeding industry. Since breeding decisions are made centrally and, increasingly, internationally, strategic change is only
likely to occur if it is embedded in an international agreement of some kind. The aim of this paper is to describe the key
ethical issues facing animal breeding and assess the suggestion that the breeding industry itself can deal with ethical issues
by means of an ethical code. Results from recent projects involving commercial breeding enterprises are presented. 相似文献
644.
Many different approaches for national sustainable development strategies (NSDS) have been proposed since 1992, with some components common to all. A country's national strategy should be designed to help mainstream environmental concerns into policy. More broadly, it should coordinate local policy with global concerns, as well as integrate scientific knowledge into policy and development planning. The peer review mechanism for national strategies was piloted by France, and also involved representatives of countries from the North and the South as well as stakeholders. The peer review process allows countries to share their experience and information, and can assist them in identifying their own path to sustainable development. The business community can also contribute to sustainable development through provision of local and global public goods. Another input to sustainable development could come from the International Organization for Standardization (ISO) and its Guidance Standard on Social Responsibility (ISO 26000), as a coordinating mechanism between voluntary initiatives and binding obligations (such as international conventions). ISO standards and guidelines should therefore be integrated with national sustainable development strategies and local Agenda 21 frameworks. 相似文献
645.
646.
Analysis of flame retarded polymers and recycling materials 总被引:1,自引:0,他引:1
Riess M Ernst T Popp R Müller B Thoma H Vierle O Wolf M van Eldik R 《Chemosphere》2000,40(9-11):937-941
Recycling activities on polymeric materials are increasing and becoming more and more important in recent years. For polymers containing no flame retardants, suitable recycling strategies already exist. In order to investigate the recyclability of flame retarded polymers that contain brominated flame retardants, a number of samples were analysed as received from a recycling company. Following the identification and sorting of the samples according to type of polymers and flame retardants, material recycling was tested for the flame retarded polymers identified to occur most frequently. The reactivity of the flame retardants during the recycling procedure was studied by analysing for brominated dioxins and furans. The results demonstrate that flame retarded polymers can be recycled under certain experimental conditions. 相似文献
647.
Christian Mulder Henri A. Den Hollander J. Arie Vonk Axel G. Rossberg Gerard A. J. M. Jagers op Akkerhuis Gregor W. Yeates 《Die Naturwissenschaften》2009,96(7):813-826
The large range of body-mass values of soil organisms provides a tool to assess the ecological organization of soil communities.
The goal of this paper is to identify graphical and quantitative indicators of soil community composition and ecosystem functioning,
and to illustrate their application to real soil food webs. The relationships between log-transformed mass and abundance of
soil organisms in 20 Dutch meadows and heathlands were investigated. Using principles of allometry, maximal use can be made
of ecological theory to build and explain food webs. The aggregate contribution of small invertebrates such as nematodes to
the entire community is high under low soil phosphorus content and causes shifts in the mass–abundance relationships and in
the trophic structures. We show for the first time that the average of the trophic link lengths is a reliable predictor for
assessing soil fertility responses. Ordered trophic link pairs suggest a self-organizing structure of food webs according
to resource availability and can predict environmental shifts in ecologically meaningful ways.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to all users. 相似文献
648.
Field investigations were conducted to measure subsoil trace element content and factors influencing content in an intensive periurban
market garden in Chenggong County, Yunnan Province, South-West China. The area was divided into three di erent geomorphological
units: specifically, mountain (M), transition (T) and lacustrine (L). Mean trace element content in subsoil were determined for Pb (58.2
mg/kg), Cd (0.89 mg/kg), Cu (129.2 mg/kg), and Zn (97.0 mg/kg). Strong significant relationships between trace element content in
topsoil and subsoil were observed. Both Pb and Zn were accumulated in topsoil (RTS (ratio of mean trace element in topsoil to subsoil)
of Pb and Zn >1.0) and Cd and Cu in subsoil (RTS of Cd and Cu 61.0). Subsoil trace element content was related to relief, stoniness,
soil color, clay content, and cation exchange capacity. Except for 7.5 YR (yellow-red) color, trace element content increased with color
intensity from brown to reddish brown. Significant positive relationships were observed between Fe content and that of Pb and Cu.
Trace element content in mountain unit subsoil was higher than in transition and lacustrine units (M > T > L), except for Cu (T > M >
L). Mean trace element content in calcareous subsoil was higher than in sandstone and shale. Mean trace element content in clay texture
subsoil was higher than in sandy and sandy loam subsoil, and higher Cu and Zn content in subsoil with few mottles. It is possible to
model Pb, Cd, Cu, and Zn distribution in subsoil physico-chemical characteristics to help improve agricultural practice. 相似文献
649.
650.