ROOT ABSORBING AND SEEPAGE MODEL IN WEIGHTLESS ENVIRONMENT AND SPACE

The exterior stimulated growth and endogenous growth of plant roots have been the focus of the content of scientists' study over the years which has not reached a consensus. The research on the influence of gravity on root growth is one of the important parts of the study. In this paper, the study on the root water uptake from the perspective of soil moisture and set up a geometric mathematical model of roots and water seepage model under weight loss environment was carried out. Through numerical calculation and analysis, the relationship between distribution of soil moisture and root water uptake under gravity environment and weight loss environment has been obtained. It is concluded that gravity hinders the root absorption of water and the weightless environment is more conducive to the absorption of water while the weight loss also cause the loss of water. Previous studies only considered the effect of gravity and light on the distribution of biological molecular constituents of the plant roots. In this paper, the effect of gravity on the soil moisture distribution will also be studied. This study is helpful in research on the hydrotropism and muck-tropism gravitropism of plant and backlighting.

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