• 2019-2023close
• Natural Sciences and Engineering Research Council of Canada close
• CA close
• figshare close
• Transport Research close

The main petroleum product transported through pipelines in Canada is diluted bitumen (dilbit), a semi-liquid form of heavy crude oil mixed with natural gas condensates to facilitate transport. The weathering, fate, behaviour, and environmental effects of dilbit are crucial to consider when responding to a spill, however few environmental studies on dilbit have been completed. Here we report on 11-day long experimental spills of dilbit (Cold Lake Winter Blend) in outdoor micro-cosms meant to simulate a low-energy aquatic system containing natural lake water and sedi-ments treated with a low (1:8,000 oil:water) and high (1:800 oil:water) volume of dilbit. In the first 24 hours of the experiment, volatile hydrocarbons quickly evaporated from the dilbit, result-ing in increased dilbit density and viscosity. These changes in dilbit’s physical and chemical properties ultimately led to its submergence after 8 days. We also detected rapid accumulation of polycyclic aromatic compounds in the water column of the treated-microcosms following the spills. Our study provides new information on the environmental fate and behaviour of dilbit in a freshwater environment that will be critical to environmental risk assessments of proposed pipe-line projects. In particular, our study demonstrates the propensity for dilbit to sink under ambient environmental conditions in fresh waters typical of many boreal lakes.

Subroutine to calculate soil modulus as a as a power function of the confining stresses

Additional file 1: Fig. S1. A-C – Syssomonas multiformis sucks out the cytoplasm of the prey; D – three cells of Syssomonas (s) suck out the cytoplasm of the same prey cell together, other Syssomonas cells (arrows) become attracted and swim to the same prey cell; E – unusual flagellated cell of Syssomonas containing vesicular structures; F – cells of Syssomonas with engulfed starch granules swim to the starch crystals druse and hide within the starch crystals. Fig. S2. Rice grain destruction in Petri dish with Pratt medium and presence of the cells of Parabodo caudatus (p rey) only (A) and Syssomonas multiformis (B) after 9 days of incubation.

1) Videos of morphology, life cycle, and feeding of novel predatory unicellular relatives of animals for "Insights into the origin of metazoan multicellularity from predatory unicellular relatives of animals"Video 1. Swimming of Syssomonas multiformis cell with rotation. Video 2. Attached cell of Syssomonas multiformis and rapid flagellum beating. Video 3. Amoeboflagellate stage of Syssomonas multiformis. Cells of eukaryotic prey Parabodo caudatus are also visible. Video 4. Loss of flagellum in Syssomonas multiformis and transition to amoeba. Video 5. Transformation of amoeba into a cyst in Syssomonas multiformis. Video 6. Palintomic divisions inside the cyst of Syssomonas multiformis. Video 7. Division into two cell structures in Syssomonas multiformis. Video 8. Cell and cyst of Syssomonas multiformis with vesicular structures inside. Video 9. Feeding of Syssomonas multiformis on eukaryotic prey. Video 10. Feeding of Syssomonas multiformis on bacteria. Video 11. Temporary cell aggregations of Syssomonas multiformis. Video 12. Floating rosette-like aggregation of Syssomonas multiformis. Video 13. Syncytium-like structures and budding of young flagellated daughter cells in Syssomonas multiformis. Video 14. Joint feeding of Pigoraptor vietnamica on dead cell of Parabodo caudatus. Video 15. Joint feeding of Pigoraptor chileana on dead cell of Parabodo caudatus. Video 16. Temporary cell aggregation of Pigoraptor chileana.2) Tree files (as newick and pdf files) and corresponding alignments for "Insights into the origin of metazoan multicellularity from predatory unicellular relatives of animals""alpha_amylase_1_LG_I_G4_1000UFboot_newick.tre": raw tree file in newick format of alpha amylase 1, corresponding to Table 1. Tree reconstruction performed with IQ-TREE (selected model based on ModelFinder: LG+I+G4, branch support was assessed with 1000 ultrafast bootstrap replicates)."alpha_amylase_1_LG_I_G4_1000UFboot.tre.pdf": unrooted tree of alpha amylase 1 as pdf file, corresponding to Table 1. Colored by lineage."alpha_amylase_1_trimal0.8.fasta": trimmed alignment used for tree reconstruction of alpha amylase 1"alpha_amylases_2_3_4_5_LG_R10_1000UFboot_newick.tre": raw tree file in newick format of alpha amylases 2-5, corresponding to Table 1. Tree reconstruction performed with IQ-TREE (selected model based on ModelFinder: LG+R10, branch support was assessed with 1000 ultrafast bootstrap replicates)."alpha_amylases_2_3_4_5_LG_R10_1000UFboot.tre.pdf": unrooted tree of alpha amylases 2-5 as pdf file, corresponding to Table 1. Colored by lineage."alpha_amylases_2_3_4_5_trimal0.8.fasta": trimmed alignment used for tree reconstruction of alpha amylases 2-5"alpha_glucosidases_1_2_3_4_LG_R10_1000UFboot_newick.tre": raw tree file in newick format of alpha glucosidases 1-4, corresponding to Table 1. Tree reconstruction performed with IQ-TREE (selected model based on ModelFinder: LG+R10, branch support was assessed with 1000 ultrafast bootstrap replicates)."alpha_glucosidases_1_2_3_4_LG_R10_1000UFboot.tre.pdf": unrooted tree of alpha glucosidases 1-4 as pdf file, corresponding to Table 1. Colored by lineage."alpha_glucosidases_1_2_3_4_trimal0.8.fasta": trimmed alignment used for tree reconstruction of alpha glucosidases 1-4"glycogen_debranching_enzyme_AGL_LG_R7_1000UFboot_newick.tre": raw tree file in newick format of glycogen debranching enzyme AGL, corresponding to Table 1. Tree reconstruction performed with IQ-TREE (selected model based on ModelFinder: LG+R7, branch support was assessed with 1000 ultrafast bootstrap replicates)."glycogen_debranching_enzyme_AGL_LG_R7_1000UFboot.tre.pdf": unrooted tree of glycogen debranching enzyme AGL as pdf file, corresponding to Table 1. Colored by lineage."glycogen_debranching_enzyme_AGL_trimal0.8.fasta": trimmed alignment used for tree reconstruction of glycogen debranching enzyme AGL"glycogen_phosphorylase_PYG_LG_R10_1000UFboot_newick.tre": raw tree file in newick format of glycogen phosphorylase PYG, corresponding to Table 1. Tree reconstruction performed with IQ-TREE (selected model based on ModelFinder: LG+R10, branch support was assessed with 1000 ultrafast bootstrap replicates)."glycogen_phosphorylase_PYG_LG_R10_1000UFboot.tre.pdf": unrooted tree of glycogen phosphorylase PYG as pdf file, corresponding to Table 1. Colored by lineage."glycogen_phosphorylase_PYG_trimal0.8.fasta": trimmed alignment used for tree reconstruction of glycogen phosphorylase PYG