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This paper aims to be a cursory relative comparison between applications of custom-designed constructed wetland systems for specific water resources protection in Canada and northern China. Comparing constructed wetlands can be difficult and at times misleading; they are custom built to deal with specific target wastewater at specific locations and differ not only in physical shape and dimension, but in vegetation cover, hydraulic retention time, and pollutant loading rates. Treatment efficiencies defined by the Canadian and northern Chinese experience vary considerably. Experience in both countries shows that the majority of effluent values are generally better than those required by discharge standards in Canada and China. Examples provided from both countries demonstrated that plants can play a role in constructed wetland systems and make a difference in treatment efficiency. A review of the available case studies on cold weather treatment in both countries indicates that this technology is feasible in Canada and northern China, although further monitoring data are needed to optimize wetland design and ensure that the effluent quality standards are consistently met. Constructed wetland systems in both countries have an apparent advantage in construction costs, and the costs for treatment and operation and maintenance of these systems are much lower than those of conventional wastewater treatment plants. Land requirements for constructed wetlands present one of the factors most limiting their broader use, especially in China, where land resources are scarce and population density is high. [ABSTRACT FROM AUTHOR]

Purpose - The paper's aim is to analyze changes in the relative importance of Canada as a supplier for its home markets; and, the rising importance of China versus other Canadian trading partners. Design/methodology/approach The market overlap measure (MOM) statistic, developed by Sawchuk and Yerger is used to analyze the Canadian home market shares for Canada and every other nation with sales in the Canadian market for each of 61 different NAIC sectors (56 at the four-digit NAIC level and five at the three-digit NAIC level). Findings The USA remains the most important foreign supplier to Canadian markets with a weighted average 23.6 percent market share as of 2003 (Canadian-based production having a 63.0 percent market share), US market share, however, has been declining by nearly a percentage point per year since 2000. Approximately, half of the lost US' market share has been captured by Canadian-based firms and approximateIy a quarter has been captured by Chinese production. China's growth in Canadian market share places it second behind only the USA in terms of Canadian-based farms' home market competitive exposure. Research limitations/implications - The work does not include an analysis of service sector trade flows due to inadequate data. Practical implications The MOM statistic is shown to be a useful diagnostic tool for analyzing the level of, trends in, and industries driving the competitive exposure a nation's firms have on sales in a specified market. Originality/value The MOM statistic is shown to yield better insights regarding the actual degree of competitive exposure than does the more commonly used similarity indices such as Finger-Kreinen. [ABSTRACT FROM AUTHOR]