Posters

MODELLING WOOD DECOMPOSITION AND N MINERALIZATION IN RAMIN WOOD DOWELS (GONYSTLYLUS BANCANNUS) ACROSS BIOMES, USING A COMMON CLIMATE FUNCTION FOR THE LIDET SITES
Knowing the rate at which wood decomposes and mineralizes is essential for terrestrial ecosystem and forest watershed modelling, especially in the context of tracking the amounts of C and N  sequestered, retained and released again from wood and woody debris across biogeoclimatic zones. This poster informs about the mass  and N dynamics from wooden dowels placed across North and Central America, with one half exposed to the atmosphere, and the other half moved into the soil below. Locations vary from the tropics to temperate, boreal, arctic and alpine areas, involving forests, grasslands, tundra, and wetland conditions. Typically, mass loss occurs faster than N loss, with overall loss rates fairly well quantified by simple biome and climate specifications pertaining to (i) annual precipitation and mean monthly January and July temperatures, (ii) ecosystem type (biome), and (iii) extent of dowel exposure. Data source: courtesy Mark Harmon and the LIDET team.For a similar approach concerning mass and N dynamics in forest litter, go to:C-F. Zhang, F-R. Meng, J.S. Bhatti, J.A. Trofymow, P.A. Arp. Modeling forest leaf-litter decomposition and N mineralization in litterbags, placed across Canada: A 5-model comparisonEcological Modelling. 2008, Volume 219, Issues 3-4, Pages 342-360. Data source: courtesy A. Trofymow and and the CIDET team.
IMPACTS OF BIOMASS HARVESTING ON NUTRIENT BUDGETS
Allocating forest stands for forest biomass harvesting, or the extraction of harvest residues following the exporting of commercially important logs from scheduled harvest blocks, has become a pressing forest sustainability  issue. This poster informs about the research and GIS procedures used to determine the sustainability of forest biomass harvesting in the context of (i) matching primary nutrient supplies (N, Ca, Mg, K, P) through atmospheric deposition and soil weathering with primary harvest exports (stem-only, whole tree with and without foliage); (ii) soil resistance to mechanical disturbance based on high-resolution upland-wetland mapping. The methods are applied to all of Nova Scotia, at the forest stand level. GIS datalayers used for doing this refer to (i)  updated soil layers accounting for all aready digitized wetlands and digitally defineable floodplains and wet areas, at high resolution (10 m), (ii) updated forest inventory layer (% tree composition), (iii) atmospheric  deposition and climate conditions (air temperature, precipitation). The biomass and nutrient export calculations are based on species-specific look-up tables by tissue type (wood, bark, branches & twigs, foliage). For  details concenring a case application for the orovince of Nova Scotia, Canada, click on the poster icon on the left.