No description available.

The hunting economy of Cumberland Sound is analyzed according to the spring, break-up and open water seasons. Physical, biological and cultural factors interact in different manners and degrees to produce seasonal variations in the miles travelled per hunt, the duration of the hunt, the catch per man per day, the percentage loss of seals due to sinking, the miles travelled per seal landed, and the number of shots fired per seal killed. If the hunt is mechanized during all three seasons, then in terms of number of seals landed per hunter per day and net profit per landed seal, hunting is most efficient during the break-up season.

No description available.

Morphology related to the South Saskatchewan River in the Outlook Saskatoon region is basically a product of the complex relationships between fluvial activity, glacial and lacustrine history and surficial materials. / During deglaciation, the river experienced numerous major changes before becoming incised in its present location. Channel scars and deltaic-alluvial deposits are widespread. / The present valley proper shows marked local variation in overall width; terrace characteristics; occurrence of slumping, and features of the valley floor including floor and river widths, gradients, braiding, meandering, channel bars and islands, and flood plain characteristics and development. Differences are largely the result of (a) pronounced variations in the resistance to erosion of materials of the valley sides and floor; (b) the influence of an alluvium-filled gut, underlying the river in the south, on width and slumping; and (c) the influence, in the north, of sharp bends which were inherited from a braided network of early high-level channels.

Morphology related to the South Saskatchewan River in the Outlook Saskatoon region is basically a product of the complex relationships between fluvial activity, glacial and lacustrine history and surficial materials. / During deglaciation, the river experienced numerous major changes before becoming incised in its present location. Channel scars and deltaic-alluvial deposits are widespread. / The present valley proper shows marked local variation in overall width; terrace characteristics; occurrence of slumping, and features of the valley floor including floor and river widths, gradients, braiding, meandering, channel bars and islands, and flood plain characteristics and development. Differences are largely the result of (a) pronounced variations in the resistance to erosion of materials of the valley sides and floor; (b) the influence of an alluvium-filled gut, underlying the river in the south, on width and slumping; and (c) the influence, in the north, of sharp bends which were inherited from a braided network of early high-level channels.

Morphology related to the South Saskatchewan River in the Outlook Saskatoon region is basically a product of the complex relationships between fluvial activity, glacial and lacustrine history and surficial materials. / During deglaciation, the river experienced numerous major changes before becoming incised in its present location. Channel scars and deltaic-alluvial deposits are widespread. / The present valley proper shows marked local variation in overall width; terrace characteristics; occurrence of slumping, and features of the valley floor including floor and river widths, gradients, braiding, meandering, channel bars and islands, and flood plain characteristics and development. Differences are largely the result of (a) pronounced variations in the resistance to erosion of materials of the valley sides and floor; (b) the influence of an alluvium-filled gut, underlying the river in the south, on width and slumping; and (c) the influence, in the north, of sharp bends which were inherited from a braided network of early high-level channels.

No description available.

No description available.

No description available.

Le cycle du carbone (C) est, depuis la révolution industrielle, déstabilisé par l’introduction dans l’atmosphère de C autrefois fossilisé. Certaines mesures de mitigation prometteuses impliquent la séquestration accrue du CO2 atmosphérique dans les sols via le développement du réseau racinaire des arbres. Ce projet de recherche visait à : 1) quantifier la biomasse racinaire ligneuse produite annuellement par unité de surface par le Salix miyabeana cultivé en régie intensive à courtes rotations, 2) doser la concentration en C et en N des racines de saule en fonction de leur profondeur et de leur diamètre et 3) déterminer l’influence des propriétés pédoclimatiques du milieu sur la séquestration du carbone organique (Corg) par les racines. Pour y arriver, six souches de saules ont été excavées à partir de huit sites (n=48) et neuf carottes de recolonisation ont été implantées à cinq sites (n=45) pour évaluer la productivité racinaire fine. Les échantillons séchés ont été pesés pour quantifier la biomasse racinaire produite, et ont été analysés pour le C et le N. La productivité en biomasse racinaire ligneuse du saule en plantation pour tout le réseau d'échantillonnage varie de 0,7 – 1,8 Mg/ha/an. La proportion de C dans la biomasse racinaire s’étend de 31,3% à 50,4% et sa variance dans les tissus est expliquée par le diamètre racinaire et par les conditions environnementales des sites de provenance. Les conditions climatiques constituent la principale influence sur la production de biomasse racinaire. La variance de la biomasse racinaire est significativement contrôlée (p :0,004) par la quantité de précipitation de l’été et de l’année qui contrôlent ensemble 83,4 % du r2 ajusté. La précipitation de l’été est inversement liée à la productivité racinaire puisque les protéines expansines des racines sont stimulées par les carences hydriques du sol. La production de racines fines des plantations (1,2 à 2,4 Mg/ha/an) est, elle, plus fortement contrôlée par les conditions pédologiques du site qui expliquent 36,5% de la variance de productivité des racines fines contre 37,5% de la variance expliquée par les facteurs pédoclimatiques. Le P et le N du sol ont des rôles prépondérants sur la production de racines fines. Une disponibilité en P accrue dans le sol stimule la biomasse racinaire fine alors qu’une quantité supérieure de N dans le sol limite la croissance racinaire tout en favorisant la croissance des parties aériennes de la plante. Ce projet a permis d’améliorer notre compréhension des conditions pédologiques et climatiques qui engendrent, au Québec méridional, une productivité et une séquestration en Corg accrue dans le réseau racinaire du saule. / The carbon cycle has gone through notable changes since the industrial revolution, with the introduction of once fossilized C into the atmosphere. A number of promising mitigation solutions have been explored, including enhanced sequestration of atmospheric CO2 into soils by promoting the development of shrub trees’ root system. This research aims at: 1) quantifying total root biomass produced per unit surface per year from the short rotation coppice (SRC) of shrub willow (Salix Miyabeana), 2) obtaining the C and N concentration of roots according to diameter and depth and 3) determining the influence of pedoclimatic properties on underground C productivity. In order to achieve these goals, six willow trunks were excavated by hand from eight sites (n=45) and nine ingrowth cores were installed at five sites (n=45) to evaluate fine root productivity. The dried samples were weighted to quantify their total biomass and analyzed, for C and N content. Measured coarse root productivity at the sites varies from 0.7 to 1.8 Mg/ha/an. The C stock in the coarse root biomass varies (31.26% - 50.35%) and its variance is mainly explained by root diameter and the environmental caracteristics of the site of origin. Climatic constraints are the main influence over coarse root biomass production. Its variance is controlled (significant p: 0.004) by yearly and summer precipitations, controlling together 83.4% of the adjusted r2. Summer precipitation is negatively correlated to coarse root growth because the expansin protein content and activity within the roots is stimulated in dry environments. Fine root productivity (1.2 to 2.4 Mg/ha/year) is, however, controlled by a mix of climatic constraints and pedological constraints. There is 36.5% of the variance that is attributable to the pedological constraints and 37.5% of the variance explained by pedoclimatic constraints. The soil P and N contents have critical roles in the determination of fine root productivity. A large soil P stock stimulates fine root growth, whereas a large soil N stock limits the growth of the roots and stimulate aboveground biomass growth. This research allowed a better understanding of the conditions leading to enhanced productivity for willow SRC in the southern region of Quebec.