ENCS406 Lecture Notes - Lecture 2: Soil Texture, Seral Community, Climax Community

• School: University of Alberta
• Department: Environmental and Conservation Sciences
• Course: ENCS406
• Professor: Edward Bork

Document Summary

P:e ratio (precipitation to evaporation; how limiting is water in this environment?) Be very familiar with the factors that drive production! Variability in precipitation (coefficient of variation = cv; regulates susceptibility to drought/flooding) Parent material/soil: texture: affects rooting ability of plants, nutrient holding capacity, water infiltration rates, susceptibility to erosion. Halophytes: salt-tolerant species (indicative of saline conditions: soil type: degree of weathering and leaching affects soil tilth and plant/animal nutrient deficiencies (p, k, na) Topography: modifies cli(cid:373)ate (cid:271)(cid:455) alteri(cid:374)g the (cid:862)effe(cid:272)ti(cid:448)e gro(cid:449)i(cid:374)g (cid:272)o(cid:374)ditio(cid:374)s(cid:863) a(cid:272)ross a la(cid:374)ds(cid:272)ape catena topo-sequence. Aspect (north-facing has a shorter growing season than south facing!) Disturbance: the only one humans can somewhat control, fire: all plant communities are adapted to fire. Pre-european (bison all over the place) versus post-european grazing management (landscape split up into little parcels, all under different management, with all kinds of herbivores) Excessive grazing causes the vegetation community to retrogress (move away from climax seral stage)