Impacts of chronic marine oil pollution and the murre hunt in Newfoundland on thick-billed murre Uria lomvia populations in the eastern Canadian Arctic

We developed a deterministic and stochastic age-based matrix projection population model to assess and quantify the impact of mortality caused by chronic oil pollution and legal hunting on thick-billed murre Uria lomvia populations breeding and wintering in eastern Canada. We calculate the potential population growth rate in the absence of anthropogenic mortality sources using a modeling technique that translates absolute number of birds killed from anthropogenic mortality to potential survival rates in the absence of these anthropogenic impacts. The intrinsic growth rate of the deterministic matrix based on vital rates from Coats Island (λ_d=1.0102), as well as the stochastic growth rate (λ_s=1.0098, 95% C.I. 0.9969-1.0226), matched observed population trends. Hunting mortality reduced population growth rate by 0.020 (0.012-0.039), oiling mortality reduced population growth rate by 0.025 (0.012-0.039). Combined these sources reduced the population growth rate by 0.047 (0.033-0.610). Although thick-billed murre populations are stable or slowly growing in eastern Canada, anthropogenic sources of mortality are reducing the ability of the population to grow, and increase vulnerability in these populations to changes in their environment and other pulse perturbations. Our modeling technique could be used to assess specific anthropogenic impacts on populations where a vital rates and numbers killed are known, but no long-term trend information is available.     

Comparison of Soil Clean-up Standards for Trace Elements Between Countries: Why do they differ? (9 pages)

Goal, Scope and Background

In the nineteen nineties most European countries issued legislation on soil protection, including soil contamination. In the case of a presumed contamination, soil investigation mostly follows a stepwise approach starting with a preliminary investigation, then an in-depth investigation and, finally, remediation. Soil clean-up standards are often foreseen as trigger criteria to determine the need for an in-depth soil investigation or for remediation. There are however large differences in soil clean-up standards. This is partly because of the different roles of soil clean-up standards in each legislative framework and partly because of differences in the soil clean-up standard (SCS) derivation procedures. Despites these differences there are large similarities in the concepts of the derivation procedures for clean-up standards. A better understanding of the differences in clean-up standards is needed. In order to clarify the variation, the background of the clean-up standards for a selected number of countries was investigated. The objective of this paper is to investigate the underlying reason why country-wide generic soil and groundwater clean-up standards of eight trace elements (cadmium, chromium (III), copper, mercury, lead, nickel, zinc and arsenic) differ between the selected countries.

Main Features

To avoid misinterpretation of the differences in application of the clean-up standards, a short overview of the legislative role of clean-up standards is given first. Differences in model concepts and parameter values are discussed, followed by a comparison of the generic soil and groundwater clean-up standards for trace elements and a discussion on the sources of variation. The influence of the use of ecotoxicological criteria and data for the derivation of soil clean-up standards will be discussed in more detail. Selected countries were Canada, the Flemish Region (Belgium), France, Germany, Great-Britain, the Netherlands, Norway, Sweden, Switzerland and United States of America (USA).

Results and Discussion

When soil clean-up standards for eight trace elements (cadmium, chromium (III), copper, mercury, lead, nickel, zinc and arsenic) were compared between the selected countries differences of more than a factor 1000 arose. Notwithstanding the use of similar derivation procedures, differences were caused by the use of different software models with their specific input data, boundary conditions and applied protection criteria for humans and the ecology. Ecotoxicological criteria tend to lower the soil clean-up standard for the selected trace elements.

Conclusions

In the countries that are included in this study, clean-up standards are used is different ways, this is for the determination of the necessity for remediation or for the need for further soil investigation. This paper shows a wide variation in the clean-up standards, which has further implication on the decision for remediation or further investigation and, hence, the financial costs of soil management. All the clean-up standards have as primary goal the protection of human health. A number of countries also include the protection of the ecological function of the soil. Differences in selected software model, (standard) parameters values, selected human toxicological and ecotoxicological criteria, are reason for a substantial variation in the clean-up standards for trace elements.

Recommendations and Perspective

. Is this variation justified? The derivation of soil clean-up standards involves - besides scientific elements - political elements, like differentiation in landuse types (agricultural, residential, recreational, industrial), receptor at risk or protection level. It is obvious that harmonization of these elements will be complicated. However, a European action programme, like the thematic strategy for soil protection, could initiate this process of harmonization. Nevertheless, soil-clean-up standards could never be uniform over the whole of Europe because they include country specific elements (geographical, ethnological) and political decisions.     

A Retrospective Economic Analysis of the Ontario Red Fox Oral Rabies Vaccination Programme

Ontario initiated a red fox (Vulpes vulpes ) oral rabies vaccination (ORV) programme in 1989. This study utilized a benefit‐cost analysis to determine if this ORV programme was economically worthwhile. Between 1979 and 1989, prior to ORV baiting, the average annual human post‐exposure treatments, positive red fox rabies diagnostic tests and indemnity payments for livestock lost to rabies were 2248, 1861 and $246 809, respectively. After baiting, from 1990 to 2000, a 35%, 66% and 41% decrease in post‐exposure treatments, animal rabies tests and indemnity payments was observed, respectively. These reductions were viewed as benefits of the ORV programme, whereas total costs were those associated with ORV baiting. Multiple techniques were used to estimate four different benefit streams and the total estimated benefits ranged from $35 486 316 to $98 413 217. The annual mean ORV programme cost was $6 447 720, with total programme costs of $77 372 637. The average benefit‐cost ratios over the analysis period were .49, 1.06, 1.27 and 1.36, indicating overall programme efficiency in three of the four conservative scenarios.     

Transnationalism through the life course: Hong Kong immigrants in Canada

Abstract: Transnationalism needs to be understood as a set of practices fashioned through the life course as well as in relation to contextual factors that include state policy and experiences of discrimination that affect entry to the labour force. The paradox of transnationalism is that families make strategic decisions to separate in order to maintain family unity and to advance the welfare of children. Emigrants from Hong Kong to Canada in the latter decades of the twentieth century were motivated by concern for family welfare and the quality of education in Canada. Yet economic livelihood prospects remained greater in Hong Kong than in Canada, prompting many families to become transnational ‘astronaut’ families with one or more members working in Hong Kong. Migration decisions tend to occur around key points of life‐course transition involving entry to and graduation from education, and entry to and exit from the labour force. Transnational practices are complex and multigenerational, involving different patterns for young adults, those in their middle years and the elderly.     

School food environments and the obesity issue: content,structural determinants,and agency in Canadian high schools

To understand the phenomenon of the rapidly increasing prevalence of overweight and obese children and youth, it is especially important to examine the school food environment, the role of structural factors in shaping this environment, and the resulting nutrition and health outcomes. The paper examines research on school food environments in the US and Canada. It notes evidence of widespread availability of poor nutrition products in both environments and delineates reasons for the situation, and examines initiatives presently being undertaken in a number of jurisdictions in both countries to encourage healthy eating in schools. Empirical data are presented from a pilot study of high schools in the Canadian province of Ontario. The study documents the extent of student purchasing of nutrient-poor foods and beverages, and the structural factors internal and external to the school that appear responsible for the availability of such products in food environments in this critical institutional sphere. The paper also examines positive local initiatives in high schools that seek to encourage healthy eating in schools.

Renovating dependency and self-reliance for participatory sustainable development

Dependency stands for manygrievances and is generally considered asymptom of oppression. An opposing concept,offered as the preferred state, isself-reliance. Dependency and self-reliance arekey concepts in sustainable developmentprograms that feature participatory approaches.Some of the ways in which development projectsemploy the concepts of dependency andself-reliance, however, are troubling.Dependency and self-reliance in two programsfor participatory sustainable development areexamined, one in Canada and the other in NewZealand. Frameworks for dependency and self-reliance aredrawn from social psychology and philosophy toexamine problematic aspects associated with theconcepts. Analysis produced a proposal foruse of the term situatedinterdependence as a way to cast the outcomesof participatory sustainable development moreprecisely. The location of the cases (Canadaand New Zealand) centers the discussion withina context of industrialized agriculture, butalso points to issues pertinent to developingcountries.     

加拿大优质春小麦种子产业化技术体系及其对我们的启示

通过参加加拿大优质春小麦种子产业化体系培训考察,了解并介绍了加拿大优质春小麦种子产业,并对我省春小麦种子产业的发展建设提出建议。     

Database Keeps Tabs on Canadian Agri-Food Research

No abstract available for this article.     

Climate-based estimates of forage yields in the prairie region of western Canada

Abstract. A forage model (FORYLD) was used to estimate average potential (constraint-free) yields ( B _y) and yields under rainfed conditions ( B _ya) of alfalfa and wheatgrasses for the prairie region of Western Canada. Yield estimates were determined using 30-year climatic means (monthly values) and assumed available water-holding capacities (AWC) of soils ranging from 50 to 280 mm as inputs to the model. Calculations were made for 252 areas or zones known as Agroecological Resource Areas (ARAs) for the region. Estimates of B _y for alfalfa ranged from over 17.5 t/ha, in areas where three cuts of alfalfa were feasible if the crop were fully irrigated, to less than 10 t/ha in some northern ARAs where restricted length of the growing season limited potential to only one cut. For wheatgrasses B _y ranged from 15 to 17.5 t/ha in most areas where two cuts are possible. Estimates of B _ya for alfalfa, based on the predominant AWC for soils in each ARA, ranged from less than 2 t/ha in the driest portion of the prairie region to more than 8 t/ha in the more humid areas. Yields of wheatgrasses were very similar to those of alfalfa in the driest zones but slightly more in some of the more humid regions. Effects of varying soil AWC on yield estimates are presented for the major soil groups of the prairies.     

加拿大兽药管理体系及其对我国的启示

全面概述了加拿大的兽药管理体系,包括加拿大的兽药定义、主要管理机构及其职责和任务、兽药管理的法律法规和主要内容等,进而对加拿大在兽药管理制度及体系方面的改革和完善进程做一简要介绍,为我国兽药法制化管理的进一步发展提供了可借鉴的信息。