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Roots not only in forest ecosystems can absorb and transfer the solute and water , as well as support the important role of the tree and consolidation of soil , slow shallow landslides, avalanches and other gravity erosion . The papers selected common in North China North ditch forest trees : pine , birch , larch, Mongolian oak , tensile test measured the tensile mechanical properties , and to provide basic information data , aimed at the study of tree roots provide some references . Test results show that : the tree root tensile strength and root diameter negative correlation , and a power law relationship . The relationship between the maximum tensile strength of the root diameter , and a power law relationship . Under the conditions of the same diameter gauge smaller roots larger tensile strength and tensile strength , in the case of smaller diameter , each gauge tensile strength and tensile strength difference is not obvious , but with a diameter the increase in the gap increases . Root of the stress-strain curve analysis , are smaller in diameter , with an increase in strain , the stress increases linearly and showed good linear elastic relationship , the diameter increases , the stress-strain curve is increasing slowly , there is no obvious linear interval . With the increase in diameter , root tensile strength , elongation , modulus of elasticity corresponding to reduce the stress - strain curve of the elastic was not obvious . Distance increasing with the root labeled root tensile strength , residual strain is reduced accordingly, the modulus of elasticity is large . 400mm/min and 10mm/min rate tensile The roots of most of brittle fracture at 400mm/min easy to pull off the destruction . The same root diameter , the larger the stretching rate , root tensile strength , tensile strength is smaller ; larger root diameter , root extension rates tensile strength , tensile strength differences become larger . Root axial fatigue reciprocating test , fatigue roots after anti - tension and tensile strength was significantly higher , showed a decreasing trend with the increase of the cycle , the elastic modulus of the same diameter , each cycle strain is reduced accordingly .
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