David Attenborough The Fascinating Life Cycle of Desert Plants Nature Bites

Nature Bites · ⏱ 5:41 · 2.2M مشاهدة · 4 years ago

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some desert plants that live in exceptionally hot dry conditions take even more drastic measures leaves are very thin and have large surface area so they lose lot of moisture in heat and many desert plants have done without them altogether instead the valuable green pigment develops in the stems and desert stems are often very thick and swollen and that enables plant to store water in them not only that but some desert plants have pleats in these stems so that when there is sudden rainstorm those ridges can suck up all the moisture while it's there and expand in order to hold it the stems of some of these species swell to such degree that they become almost spherical sphere has minimum surface area for any given volume and that enables the plant to hold as much water as possible this one is copia power from northern chile where it never rains at all but in fact it doesn't need it under microscope you can see why there are thousands of tiny jagged structures on which the morning dew condenses so that the plant can collect it but the ultimate is this plant it's hidden between these light-colored pebbles blossom from argentina this is the only flowering plant that can withstand total desiccation for months on end and then with shower of rain or little bit of water it comes to life and produces tiny little flower this ability to wait for the right conditions is the trump card that enables many plants to survive in the dry zone in many deserts plants must endure months sometimes years of drought they do it by slowing down their metabolism and going into state of virtual dormancy but when rains finally arrive plants like these suddenly come to life their dried-out tissues absorb water like sponges and once expanded they use the moisture to grow this primitive rootless plant from the chihuahua desert in mexico is spike moss selaginella it's also called the resurrection plant because of its ability to seemingly come back from the dead rain starts complex biochemical change in itself that enables it to ramp up its metabolism and grow very quickly while it can but the most spectacular consequence of rain in the desert is an explosion of color desert flowers are as colorful as any in the world they have to attract pollinators quickly before the deserts dry out once again but moisture in the soil can evaporate almost as quickly as it arrives and after brief bloom they die you