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601.
Importance of information on tillage practices in the modelling of environmental processes and in the use of environmental indicators 总被引:1,自引:0,他引:1
Tillage has been and will always be integral to crop production. Tillage can result in the degradation of soil, water, and air quality. Of all farm management practices, tillage may have the greatest impact on the environment. A wide variety of tillage equipment, practices and systems are available to farmers, providing opportunities to enhance environmental performance. These opportunities have made tillage a popular focus of environmental policies and programs such as environmental indicators for agriculture. This paper provides a very brief examination of the role of tillage in crop production, its effect on biophysical processes and, therefore, its impact on the environment. Models of biophysical processes are briefly examined to demonstrate the importance of tillage relative to other farm management practices and to demonstrate the detail of tillage data that these models can demand. The focus of this paper is an examination of the use of information on tillage in Canada's agri-environmental indicators initiative, National Agri-environmental Health Analysis and Reporting Program (NAHARP). Information on tillage is required for several of the indicators in NAHARP. The type of data used, its source, and its quality are discussed. Recommendations regarding the collection of tillage data and use of tillage information are presented. 相似文献
602.
In New Zealand environmental management is essentially the responsibility of land managers. Management decisions affect both production/productivity and the environment. However, responsibility for ensuring positive environmental outcomes falls on both local (Regional) and Central Government, and both they and international agencies such as the OECD would wish to monitor and report on changes. In terms of policy, strong links have been established via Central and Regional Government to land managers. Consumers in the market place are also, increasingly, requiring responsibility for positive environmental outcomes of those who purchase and process primary products. Strong links for responsibility have been established between our international markets and processing businesses and there is a noticeable strengthening of the links from the processors to the land manager/producer. In New Zealand a range of initiatives has been developed and implemented over recent times, whereby land managers are taking increasing responsibility for accounting for the environmental outcomes of their production activities. The range covers the spectrum from voluntary to compulsory (e.g., in order to meet market requirements) and from those initiated by customers to processor and/or producer initiatives. This paper follows the evolution of the principles that drove the predominant activities of the period and the processes that initiated the changes in environmental management. As the focus of agriculturalists changed from pioneering in a new world, to establishing a production base, to economic reality, and finally to environmental responsibility, the processes of extension adapted to meet the new challenge. 相似文献
603.
Faced with society's increasing expectations, the Common Agricultural Policy (CAP) review considers environmental management to be an ever more critical criterion in the allocation of farm subsidies. With the goal of evaluating the environmental friendliness of farm practices, France's agricultural research and extension services have built a range of agricultural/environmental diagnostic tools over recent years. The objective of the present paper is to compare the five tools most frequently used in France: IDEA, DIAGE, DIALECTE, DIALOGUE and INDIGO. All the tools have the same purpose: evaluation of the impact of farm practices on the environment via indicators and monitoring of farm management practices. When tested on a sample of large-scale farms in Picardie, the five tools sometimes produced completely different results: for a given farm, the most supposedly significant environmental impacts depend on the tool used. These results lead to differing environmental management plans and raise the question of the methods' pertinence. An analysis grid of diagnostic tools aimed at specifying their field of validity, limits and relevance was drawn up. The resulting comparative analysis enables to define each tool's domain of validity and allows to suggest lines of thought for developing more relevant tools for (i) evaluating a farm's environmental performance and (ii) helping farmers to develop a plan for improving practices within the framework of an environmental management system. 相似文献
604.
The invasion of water hyacinth (Eichhornia crassipes) has resulted in enormous ecological and economic consequences worldwide. Although the spread of this weed in Africa, Australia,
and North America has been well documented, its invasion in China is yet to be fully documented. Here we report that since
its introduction about seven decades ago, water hyacinth has infested many water bodies across almost half of China’s territory,
causing a decline of native biodiversity, alteration of ecosystem services, deterioration of aquatic environments, and spread
of diseases affecting human health. Water hyacinth infestations have also led to enormous economic losses in China by impeding
water flows, paralyzing navigation, and damaging irrigation and hydroelectricity facilities. To effectively control the rampage
of water hyacinth in China, we propose a sustainability science-based management framework that explicitly incorporates principles
from landscape ecology and Integrated Pest Management. This framework emphasizes multiple-scale long-term monitoring and research,
integration among different control techniques, combination of control with utilization, and landscape-level adaptive management.
Sustainability science represents a new, transdisciplinary paradigm that integrates scientific research, technological innovation,
and socioeconomic development of particular regions. Our proposed management framework is aimed to broaden the currently dominant
biological control-centered view in China and to illustrate how sustainability science can be used to guide the research and
management of water hyacinth. 相似文献
605.
Copper is the biocide of choice for present-day antifouling (AF) paints. It is also a major source of copper loading in to
the marine environment and, as such, might cause local copper levels to exceed water quality criteria. The present study is
multifaceted and looks into the overall impact of copper-based AF paints on copper concentrations along a 64-km stretch of
the Indian River Lagoon and at Port Canaveral, Florida. This preliminary study is one of the first to outline issues and present
background evidence on the current status of copper and copper-based AF usage in Florida and to address the need for management.
Previous measurements of copper levels in these waters show a history of copper contamination close to marinas, boatyards,
and at Port Canaveral that often exceed state and federal water quality standards. Further, we estimate that the total annual
copper input into the Indian River Lagoon is between 1.7 tons/year (sailboats) and 2.1 tons/year (powerboats) from boats in
14 marinas. We estimate the copper input into Port Canaveral to be about 1.4 tons/year from seven cruise ships. A brief survey
of marina operators and boat owners revealed attitudes and practices associated with AF paint usage that ranged from excellent
to inferior. Management recommendations are made for a proactive approach to improving AF paint selection and application,
assessing the environmental status of copper, and redefining existing management practices for sustainable AF paint usage
and environmental health. 相似文献
606.
This Φ Ψ study of environmental equity uses secondary quantitative data to analyze socioeconomic disparities in environmental
conditions in the Rijnmond region of the Netherlands. The disparities of selected environmental indicators—exposure to traffic
noise (road, rail, and air), NO2, external safety risks, and the availability of public green space—are analyzed both separately and in combination. Not only
exposures to environmental burdens (“bads”) were investigated, but also access to environmental benefits (“goods”). Additionally,
we held interviews and reviewed documents to grasp the mechanisms underlying the environmental equity situation, with an emphasis
on the role of public policy. Environmental equity is not a priority in public policy for the greater Rotterdam region known
as the Rijnmond region, yet environmental standards have been established to provide a minimum environmental quality to all
local residents. In general, environmental quality has improved in this region, and the accumulation of negative environmental
outcomes (“bads”) has been limited. However, environmental standards for road traffic noise and NO2 are being exceeded, probably because of the pressure on space and the traffic intensity. We found an association of environmental
“bads” with income for rail traffic noise and availability of public green space. In the absence of regulation, positive environmental
outcomes (“goods”) are mainly left up to market forces. Consequently, higher-income groups generally have more access to environmental
“goods” than lower-income groups. 相似文献
607.
Environmental risk perception, environmental concern and propensity to participate in organic farming programmes 总被引:4,自引:0,他引:4
This paper aims to identify the factors underlying farmers' propensity to participate in organic farming programmes in a Romanian rural region that confronts non-point source pollution. For this, we employ structural equation modelling with latent variables using a specific data set collected through an agri-environmental farm survey in 2001. The model includes one 'behavioural intention' latent variable ('propensity to participate in organic farming programmes') and five 'attitude' and 'socio-economic' latent variables ('socio-demographic characteristics', 'economic characteristics', 'agri-environmental information access', 'environmental risk perception' and 'general environmental concern'). The results indicate that, overall, the model has an adequate fit to the data. All loadings are statistically significant, supporting the theoretical basis for assignment of indicators for each latent variable. The significance tests for the structural model parameters show 'environmental risk perception' as the strongest determinant of farmers' propensity to participate in organic farming programmes. 相似文献
608.
Bergquist DA 《Environmental management》2007,40(5):787-802
This article discusses environmental sustainability in aquaculture and its contribution to poverty alleviation, based on field
studies in Sri Lanka and the Philippines. The aquaculture practices studied are the monoculture of the black tiger prawn (Penneaus monodon) and milkfish (Chanos chanos) and the polyculture of the two species together with the mud crab (Scylla serrata). Factors affecting economic viability, social equity and environmental impacts in aquaculture are discussed and used to
illuminate local and regional differences between aquaculture in Sri Lanka and the Philippines. Findings indicate that the
most significant difference is the level of participation by local people (i.e., people originating ≤10 km away from the farm
location). In the Philippines, 84 % of the people involved in aquaculture are locals, whereas in Sri Lanka, 55% are outsiders.
Whether differences between the two areas can be explained by analyzing regional conditions, which might have resulted in
different aquaculture practices, is discussed. In Sri Lanka, semi-intensive shrimp monoculture is currently the most common
practice, whereas in the Philippines, extensive shrimp/fish polyculture is more common. Previous studies, as well as fieldwork,
indicate that extensive culture practices reduce environmental impacts and benefit local people more. Sustainability in aquaculture
is, however, also dependent on the extent of mangrove conversion into ponds. As such, extensive and locally owned farms do
not necessarily result in an all but sustainable situation. Keeping this in mind, it is discussed if extensive polyculture
practices might result in a more sustainable aquaculture, both environmentally and socioeconomically. 相似文献
609.
Reed MG 《Environmental management》2007,39(1):30-49
Advocates of community-based approaches to environmental management argue that by respecting local circumstances, skills,
and concerns we may improve the prospects of achieving environmental sustainability; yet, within nation states such as Canada,
environmental conditions, management and enforcement costs and capabilities, and power differentials within and among civic
and public sectors may result in a highly differentiated capacity for environmental management across different localities
and regions. This article draws on insights of political ecology to 1) create a conceptual framework that identifies key elements
shaping regional environmental management regimes and to 2) undertake a comparative analysis to assess how elements interact
to generate uneven management outcomes. I compare experiences of two Canadian biosphere reserves designated in 2000: Clayoquot
Sound, BC; and Redberry Lake, SK. Analysis reveals that differences in governance and institutional capacities in the biosphere
reserves are key to explaining uneven local outcomes. Where the public and civic sectors are strong, a robust and publicly
vetted form of management will emerge. Where these sectors are weak and land is held as private property, environmental nongovernmental
organizations can set the type and level of management, to the exclusion of effective civic and state involvement. This result
may improve environmental sustainability but hinder social sustainability of a management regime and raises questions about
the efficacy of community-based management. 相似文献
610.
Environmental dredging is a primary remedial option for removal of the contaminated material from aquatic environment. Of
primary concern in environmental dredging is the effectiveness of the intended sediment removal. A 5-year field monitoring
study was conducted to assess the effectiveness of the environmental dredging in South Lake, China. The concentrations of
total nitrogen (TN), total phosphors, and heavy metals (Zn, Pb, Cd, Cu, Cr, Ni, Hg, and As) before and after dredging in sediment
were determined and compared. Multiple ecological risk indices were employed to assess the contamination of heavy metals before
and after dredging. Our results showed that the total phosphorus levels reduced 42% after dredging. Similar changes for Hg,
Zn, As Pb, Cd, Cu, Cr, and Ni were observed, with reduction percentages of 97.0, 93.1, 82.6, 63.9, 52.7, 50.1, 32.0, and 23.6,
respectively, and the quality of sediment improved based on the criterion of Sediment Quality Guidelines by USEPA and contamination
degree values (Cd) decreased significantly (paired t-test, p < 0.05). Unexpectedly, the TN increased 49% after dredging compared to before dredging. Findings from the study demonstrated
that the environmental dredging was an effective mechanism for removal of total phosphorus and heavy metals from South Lake.
Nevertheless, the dredging was ineffective to remove total nitrogen from sediment. We conclude that the reason for the observed
increase in TN after dredging was likely ammonia release from the sediment impairing the dredging effectiveness. 相似文献