Terrestrial_Ecosystems_Study_Sheet.docx

Stratification?seen more clearly in mature, mesic forests consisting of the canopy, understory, shrub layer, herb layer, and litter layer; allows various plant-growth forms to coexist in a given habitat; the lowest layer blooms flower/ leaves first in order to receive their needed light. Canopy?consists of the crowns of the tallest trees Understory?consists of smaller tree species (ie. Flowering Dogwood and Sassafras) Shrub Layer?consists of shrub species, usually laurels and vibernums Herb/fern layer?consists of ferns and wildflowers, particularly evident in the spring when several wildflower species (spring ephemerals) are in bloom Litter layer?found on top of the soil, consists of decomposing leaves and wood Indicator Species--plants and animals that, by their presence, abundance, lack of abundance, or chemical composition, demonstrate some distinctive aspect of the character or quality of an environment. Plants depend on climate and soil for their survival. White Basswood in Cove Forest Insectivorous insects in bogs (characterized by the acidic conditions) Brown-headed Nuthatch found only in Southern Pine-Oak Forests Species Richness (diversity)?number of species in a habitat Four forces of nature determine if a species is present in a habitat: (1) distribution and dispersal (2) physiological tolerance limits (3) biotic forces such as predation, parasitism, and disease (4) ability to cope with unpredictable forces of nature including weather, climate change, and other natural events. Soil Characteristics?product of combined effects of geology, rainfall, temperature, and vegetation; good healthy soils are the combination of sand, silt, and clay and is referred to as loams; precipitation adds to the acidity of the soil because as water moves through the soil it removes minerals attached to clay particles and leaves hydrogen atoms behind; when leaves decompose they add minerals to the soil True Spodosol?very gray in color, with a thin black band of highly decomposed material (mor humus) on the surface, digging down soil gets darker brown or even reddish; found in northern coniferous forests throughout Canada and North America; thick layer of decomposing needles found on top of soil Gray-brown Spodosol (Alfisol)?browner soils and less acidic than true spodosol, forming a humus called mull that hosts many earthworms; commonly found beneath broad-leaved deciduous forests; occurs throughout the Northeast and mid-Atlantic states Yellow Soil?yellowish on the surface and grayish yellow below; sandy compared to eastern soils,; most commonly found on the Coastal Plain from North Carolina through eastern Texas; found commonly in Pine and Pine-Oak forests; thin litter layer Red Soil (Oxisol)?ranges in color from orange-red to bright salmon, where a deeper layer of yellow-brown soil is found; found throughout the southeastern states in Southern Hardwood Forests, Southern Oak-Hickory Forests, and some Mixed Pine-Oak Forests; thin litter layer Prairie Soil (Chernozem)?deep brown at the surface and lighter brown below; occurs at the ?used-to-be? prairie in Illinois, Missouri, Iowa, Wisconsin, and Minnesota (now farmland)