MSC 316 Lecture Notes - Lecture 12: Lignin, Andropogon Gerardi, Ogallala Aquifer
Document Summary
Boreal: mixture of conifers (gymnosperm, mostly pine, spruce, larch, northern canada and russia, despite snowfall, precipitation rates in boreal forests are lower than in temperate forests. Conifer trees: better shaped for sunlight coming in at low sun angles, conical shape with needles at edges instead of broadleaf shaped tree with canopy, more efficient for high latitudes. Conifer advantages in boreal forests: conical shape. Promotes shedding of snow and prevents loss of branches; optimum for low sun angle: needle leafs. Narrow leaves reduce surface area for transpiration, important the winter when frozen ground prevents plants from water supply. Needles have thick, waxy coatings a waterproof cuticle in which stomata are sunken from drying winds: evergreen habit. Retention of foliage allows plants to photosynthesize as soon as temperatures permit in the spring, rather than having to waste time in the short growing season growing leaves: dark color. Interior of pine warmer than outside of pine. Temperate grassland biome: tall grass prairie.