The CONEstrip algorithm

Uncertainty models such as sets of desirable gambles and (conditional) lower previsions can be represented as convex cones. Checking the consistency of and drawing inferences from such models requires solving feasibility and optimization problems. We consider finitely generated such models. For closed cones, we can use linear programming; for conditional lower prevision-based cones, there is an efficient algorithm using an iteration of linear programs. We present an efficient algorithm for general cones that also uses an iteration of linear programs

Factorisation properties of the strong product

We investigate a number of factorisation conditions in the frame- work of sets of probability measures, or coherent lower previsions, with finite referential spaces. We show that the so-called strong product constitutes one way to combine a number of marginal coherent lower previsions into an independent joint lower prevision, and we prove that under some conditions it is the only independent product that satisfies the factorisation conditions

The effects of cultivar on nodulation, seed yield, and dinitrogen fixation of dry bean (Phaseolus vulgaris L.)

Non-Peer Reviewe

Soil origin and land use history determine C cycling in transplanted soils after 21 years

Non-Peer Reviewe

The use of soil amendments in the revegetation process of smelter-impacted soils

Non-Peer Reviewe

Productivity and N-fixation of legume-cereal intercrops and their monocrop counterparts in organic cropping systems

Non-Peer ReviewedIn recent years, western Canada has seen considerable growth in organic production. This is due to heightened environmental awareness, reduced input costs, diversification of market opportunities, and food safety aspects. On the prairies, organic production generally includes the use of annual green manure (GrM) crops, which are plowed under to add nutrients to the soil. However, in a GrM plow-down year, farmers face loss of income. One alternative to growing a traditional GrM could be growing legumes alone or intercropping them with cereals and managing them as green feed forage (GF) for use on-farm or for sale to local livestock producers without compromising soil fertility levels. Intercropping legumes with cereals may be a novel approach to problems of nitrogen (N) supply as the legume may provide N to the current and subsequent crops. It was hypothesized that by intercropping the legume with a cereal, the inorganic N supply would be reduced to levels where N fixation in the legume would be stimulated. This study (i) compared yield in monoculture legume with legume-cereal intercrops (ii) investigated whether increasing cereal density stimulated the legume to fix more N (iii) Compared yield of a cereal grown after the GrM and GF crop treatments. The study included mixtures of feed pea (Pisum sativum cv 40-10 silage pea), oat (Avena sativa L.cv AC Morgan), and triticale (X Triticosecale Wittmack cv Pika). The experiment consisted of 16 treatments and 4 replicates in which feed pea, oat, and triticale were grown alone or in combination and managed as GrM or GF. Wheat and fallow (tillage) served as cropped and uncropped controls respectively. The intercropped oat was seeded at three densities (50, 100, and 150 plants m-2). In the second year, wheat was seeded in all plots. In this paper, biomass, total nitrogen (N), and nitrogen derived from the atmosphere (Ndfa) of treatments and subsequent yields of wheat grown after the treatments at the Delisle site are discussed. Results show that the oat (4238 kg ha-1) and fieldpea + oat 2 (3630 kg ha-1) treatments had the highest biomass whereas the triticale (1357 kg ha-1) treatment had the lowest. Among the intercrops, only the fieldpea + oat 2 treatments had higher total nitrogen (91.61 kg ha-1) than their monocultures, with the oat treatment being the least (45 kg ha-1). The highest %Ndfa was achieved at the highest intercropped cereal density of fieldpea + oat 1 (84%). Wheat grain yield were consistently higher following GrM treatments whereas biomass removal significantly compromised subsequent wheat yields in the GF treatments

How mycorrhizal fungal bio-fertilizer impact on seed yield of field pea and wheat across Saskatchewan prairies

Non-Peer Reviewe

Response of transplanted Chernozems towards C addition after 21 years of identical climatic, topographic, and management practices

Non-Peer Reviewe

Assessing the efficacy of nitrification and urease inhibitors on reducing gaseous N losses in forage seed production of the Saskatchewan parkland region

Non-Peer Reviewe