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Production of biomass for bioenergy will depend on the sustainability of the production resource-base: the soil, water, air and the diversity of the ecosystem as a whole. For soil, potential sustainability indicators, including soil nitrogen and phosphorus, total organic matter, components associated with soil erosion and bulk density are discussed. Indicators related to the water resource water quality, water availability index, nitrate levels in water and biological oxygen demand are also discussed. Greenhouse gases and their sequestration potentials are discussed for maintaining atmospheric air quality. For biodiversity, a biodiversity index and soil biota index were selected as potential indicators. In addition to the production resource-base, the paper also discusses the importance of economic and social sustainability indices. To summarize, we are suggesting that a common method of visualizing the above indicated indices is to generate amoeba diagrams. This paper also provides a review on the term 'sustainability' and specific indicators, with metrics where possible, are described as candidates for inclusion as potential indicators appropriate for agroforestry based bioenergy systems in Canada. Three agroforestry based bioenergy systems are described and specific indicators are discussed within the bounds of these systems.

, T. 2008. Soil carbon change factors for the Canadian agriculture national greenhouse gas inventory. Can. J. Soil Sci. 88: 671Á680. Canada annually reports on all of its annual greenhouse gas emissions to the United Nations Framework Convention on Climate Change (UNFCCC), including estimates of CO 2 emissions and removals from cropland management. Soil carbon (C) change in cropland resulting from management is estimated by using C change factors multiplied by the area of cropland subjected to a management change. In this paper we compare soil C change factors in Canadian cropland obtained using a C modelling approach (Century model) to both empirical estimates obtained from the scientific literature, and to default Intergovernmental Panel on Climate Change (IPCC) estimates. Factors were estimated for land management changes from annual to perennial cropping, tillage to no-tillage and from summer fallow to continuous cropping. Empirical data comparing C change between conventional tillage (CT) and no-tillage (NT) were highly variable, but the modelled factors were still within the range derived from the empirical data. Factors for changes from CT to NT varied from 0.06 to 0.16 Mg C ha(1 yr (1 across the country. When considering the change from annual to perennial cropping, the modelled factors ranged from 0.46 to 0.56 Mg C ha(1 yr(1 , which is in the range of empirical values, and were slightly greater in the eastern than the western soil regions. For conversion of crop-fallow to continuous cropping, the modelled rate of C storage (0.33 Mg C ha(1 yr (1 ) was more than double the average rate of 0.1590.06 Mg C ha (1 yr (1 derived from two independent assessments of the literature. For each of the management changes considered, the modelled factors were generally lower than IPCC estimates, and this is partly attributable to differences in calculation methods and to the fact that C changes likely occur more slowly in the cold climate of Canada. Generally, the results show that the modelling approach used at present to derive C change factors for use in Canada's inventory is adequate. However, soil C change factors for cropland soils in Canada would be greatly improved by a reduction in the high variability usually associated with empirical data, and by improved simulation of the Century model under varying management conditions.

Malting barley is important in western Canada, yet many malting cultivars do not make malt quality, in part due to lodging. Lodging can decrease barley yield and quality thereby reducing the acceptability for malting. In other countries plant growth regulator applications are used to mitigate lodging. Chlormequat chloride (chlormequat), trinexapac-ethyl (trinexapac) and ethephon were tested at five locations over 3 years in western Canada for their ability to limit lodging, as well as their effects on yield, agronomic traits, and pre-malt quality characteristics. PGR applications occurred between GS 30-33 for chlormequat and trinexapac and GS 37-49 for ethephon. Seeding rates of 200, 300, and 400 seeds m-2 of CDC Copeland barley were used to increase the likelihood of lodging. Increased seeding rate decreased tillers per plant, height, days to maturity, kernel protein and kernel weight. Ethephon increased the number of tillers per plant, and decreased plant height, kernel plumpness and kernel weight. Trinexapac decreased plant height and kernel weight. Days to maturity was investigated across site-years with ethephon increasing maturity in 60% of comparisons. Trinexapac and chlormequat had limited effects on maturity. Lodging was investigated across site-years with trinexapac showing the largest number of lodging reductions and scale of reductions. Ethephon reduced lodging in 36% of comparisons, while chlormequat had inconsistent effects. None of the products affected yield, or grain protein. Plant growth regulators may not be the solution to lodging for CDC Copeland barley on the Canadian Prairies, however trinexapac shows the most promise of the products tested.