Arctic tundra at high latitude cold, desert-like conditions A land dotted with lakes and crossed by streams where ground is low and moist On high drier areas where ground is bare and rock- covered, vegetation is scant and scattered permafrost
frost hummocks Rounded knoll of ice Caused by slow and unequal pressure in the main body of the packed ice
Frost boil Continuous thawing and freezing pushes fragments of stone outward in a ringed patterns
Earth stripes Exaggerated stretching of frost boils produces parallel strands of rocks and soil
Alpine tundra At high altitudes Mostly confined to very high elevations Little permafrost Soils are drier Higher precipitation than in Arctic Tundra Steep topography induces a rapid runoff of water
AbioticTemperatureSoilWind and waterNutrients
Temperature short summer days ; very long and cold winters The alpine tundra is also cold, but not nearly as cold as the arctic. Temperatures at night are almost always below freezing, but daytime temperatures still permit plant growth for about half the year. limits the types of species that can live there
Soil Inactive layer (permafrost) If the permafrost melts, it alters the temperature and topography of a region, which threatens the existence of many species living in the tundra. Active layer (top of the permafrost) thaws in the summer months which allows vegetation to grow and enables the chemical processes necessary for sustaining life to occur.
Wind and water extremely windy and have small amounts of rainfall high winds make it difficult for any large plant species to survive Despite the low rainfall, the arctic has high humidity, because water is slow to evaporate
Nutrients Phosphorous and nitrogen are the major nutrients that exist in the tundra biome Precipitation produces phosphorous, while a bio- chemical process creates nitrogen. Through photosynthesis, plants harvest energy from the sun, which they use to absorb these key nutrients and grow.
Simple Structure and LowDiversity Characterize the Vegetation of Tundra
•Vegetation – simple; although it appearshomogeneous, the pattern of vegetation is patchy.The combination of micro relief, snowmelt, frost heaving, and aspect, among other conditions, produces an endless change in plant associations from spot to spot.•Number of Species – few•Growth- slow•Biomass and functional activity are confinedto a few groups.
ArcticOnly those species able to withstand constant disturbance of the soil, buffeting by the wind, and abrasion from wind- carried particle of soil and ice can survive.
•Low ground- cotton grass, sedge, dwarf heath, sphagnum mossComplex.•Well drained sites- heath shrubs, dwarf willows and birches,Dryland sedges and rushes, herbs, mosses, and lichens.•Driest and most exposed sites-(flat topped domes, rolling hills, low lying terraces)- sparse vegetation,Scattered heaths and mats of dryads, crustose and foliose lichens.
Alpine TundraThe environment is even MORE severe for plants. It is a land of strong winds, snow, cold, and widely fluctuating temperatures.
Rocky strewn slopes, bogs, alpine meadows,and shrubby thickets. Cushion and mat- forming plants , rare in Arctic, are important in the Alpine Tundra Low, and ground hugging- able to withstand win Cushionlike blanket- traps heat Interior of cushion may be 20C warmer than the surrounding air which insects use as microclimate.
•Segmented whiteworms•Collembolas•Flies•Blackflies•Deerflies•Mosquitoes-( scarce in alpine)•Beetles•Grasshoppers•Butterflies•Butterflies keep close to the ground•Other insects have short wings or no wings at all•Insectdevelopment is slow•Butterflies may take two years to mature•Grasshoppers three years
Carnivore•Wolf- dominates;preys on muskox, caribou, and lemmings•Arctic fox- preys on arctic hare, andweasels which preys on lemmings•Snowy owls and Hawklike jaegers-lemmings
Alpine Tundra•Haycutting pika, marmots, mountain woodchucks-hibernate over winter• mountain goats, sheep, elk, voles, and pocket gophers,
Human Impact• Hunting•Global warming•Oil Drilling•Over Development•Pollution