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Desert biomes By David, Michal, and Alex Climate Cold Deserts Snows in the winter Temperature in winter ranges from -2 to 4° C and in the summer 21 to 26° C a year Rains in the spring. Averages out to 15 - 26 cm of rain a year Never warm enough for plants to grow Climate hot-Dry deserts Temperature ranges from 20 to 25° C The extreme maximum temperature ranges from 43.5 to 49° C Have very little rainfall in short periods between long rainless periods Averages out to under 15 cm of rain a year. Winters have very little if any rainfall Warm throughout the fall and spring season Plants cold deserts In areas with little shade, about 10 percent of the ground is covered with plants. In some areas of sagebrush it reaches 85 percent. The height of scrub varies from 15 cm to 122 cm. All plants are either deciduous and more or less contain spiny leaves. Sego Lily Bitterbrush Rabbit Brush Sage Brush plants hot-dry deserts Vegetation is very rare. Plants are almost all ground-hugging shrubs and short woody trees. All of the leaves are replete (packed with nutrients). Turpentine Bush Prickly Pears Brittlebush. Adaptations: the ability to store water for long periods of time and the ability to stand the hot weather. soil/agriculture Hot-Dry deserts Soils are course-textured, shallow, rocky or gravely with good drainage and have no subsurface water. They are coarse because there is less chemical weathering. The finer dust and sand particles are blown elsewhere, leaving heavier pieces behind. Human impact cold deserts Irrigation altars steams, rivers, and canyons Animal grazing altars the plant community and agriculture Increased of tourists in the settled deserts is disrupting the preserved biotic soil crusts Desert landscape is being replaced with concrete, houses, lawns, etc, Irrigation may in the long term lead to salt levels in the soil that become too high to support plants Oil and gas production may disrupt sensitive habitat Nuclear waste may be dumped in deserts, also used as nuclear testing grounds Human impact hot-dry deserts Increased grazing has degraded riparian zones and altered the desert plant community and agriculture Irrigation has altered streams, rivers, and canyons Exotic and sometimes invasive species have been introduced that can quickly colonize and dominate the landscape Increased visitors to parks and natural areas have affected the biotic soil crusts of even the most preserved areas The growth of cities and ensuing suburban sprawl is replacing the once desert landscape with concrete, lawns, homes and picket fences