FRST 201 MIDTERM 2 - Topography

Latitude

influences light, temperature, seasonal changes, and rainfall

Coriolis effect

determines the predominant wind direction

global circulation pattern

drives the global precipitation patterns
highest at equator
lowest in subtropics
Suitable in temperate

regional climate

weather and growing season of a broad geographical area that shares the same precipitation patterns, atmospheric temperatures and seasonal patterns.
Elevation, altitude, major landscape feature, and proximity to large bodies of water impact regional climate

Local Climate

the climate in an area (0.1-10km) where local conditions of the Earth's surface are clearly different from those in the nearby surrounding areas
difference around hills versus rivers, lakes, forests, cities
Topography greatly impacts this

Microclimate

climate within a small area (few meters or less)
often caused by vegetation (shading and evapotranspiration)
leads to localized patches that vary in temp and moisture

Topography

can cause variations in regional, local and microclimate variation (temp and hydrology)
both temp and hydrology greatly affect rates of decomp and thus topography effects nutrient availability
Topographic features affect plant species composition, community, structure and forest productivity of a site.

Orographic effect

precipitation pattern that occurs when a warm, moist mass of air is pushed over a mountain by the prevailing winds
most pronounced when the prevailing wind travels across a warm ocean region before ascending a mountain feature
as the air rises over the mountain, it cools about -6degrees C per Km gain in elevation and causes water condensation and precipitation on the windward side
air descends on the leeward side and warms, creating a dry climate (rain shadow)

Aspect

more solar radiation on south slopes than north slopes
ample rainfall of south slope then south can be more productive than north
however if there is a water deficit on south slope it can be detrimental to plant growth

Slope and hydrology

slope position
slope angle
(influence soil moisture availability)

parent material

following rain, upper slopes shed water and are thus dryer sites
steeper slopes have higher rates of water run off and flat features do not

lower slopes receive more water and dissolved nutrients that were shed from the higher slopes (can be rich growing site if water is not in excess)

mid slopes lie within the two extremes of soil moisture and dissolved nutrients

Topography, parent material and hydrology

high content of sand and gravel have high rates of infiltration and percolation
high silt and clay content impede infiltration and percolation, resulting in greater surface water runoff
parent material affects soil moisture availability and site drainage of topographic features