高寒矿区采样位置和生长期及坡向对草本植物根系力学特性影响

以种植于青海刚察木里煤田江仓矿区排土场不同坡向（半阴半阳、阳坡和阴坡）、生长期为1~5 a的垂穗披碱草为研究对象，对该植物根系开展单根拉伸试验，测定其根径、单根抗拉力、抗拉强度、极限拉伸应变率和拉伸模量等力学指标。分别以采样位置、生长期和坡向为自变量，以上述力学指标为响应变量，通过单因素方差分析，探讨各自变量对上述指标的影响。结果表明：在半阴半阳坡和阴坡，各指标在不同取样点未表现出显著性差异，在阳坡，除根径外，其余指标均表现出显著性差异；随生长期增加，各坡向的植物抗拉力、抗拉强度等指标呈增加的变化特征；阳坡植物根径、单根抗拉力大于半阴半阳坡，而其余各指标则表现出相反的变化特征，在半阴半阳边坡，植物根系力学指标大于阴坡。

Impact of Sampling Sites,Slope Aspects and Growth Periods on the Tensile Mechanical Behavior of Roots in High-Altitude Alpine Pasture

To investigate the impact of slope positions (sampling sites), slope aspects (West-east oriented slope (CK group), shady slope and sunny slope) and growth periods on the tensile mechanical behavior of single root, Elymus nuants with its growth period of 1~5 a planted in the Jiangcang spoil bank at Muli mine site in Gangcha County, located in Qinghai Provence was selected as the tested species. And tensile tests were carried out to the roots of the selected species to measure its diameter, tensile resistance, tensile strength, tensile strain rate at crack and Young's modulus. ANOVA was conducted to analyze the impact of slope positions, slope aspect and growth period on these indices. And the results show that no difference in root diameter, tensile resistance, tensile strength, tensile strain at crack and Young's modulus for roots of E. nutans planted in both CK group and shady slopes was observed, while for those in sunny slopes, except for root diameter, other indices exhibits significant difference. For E. nutans planted in the three slopes, indices such as tensile resistance, tensile strength exhibits an increasing trend with growth period increasing. Root diameter, tensile resistance, tensile strength, tensile strain at crack and Young's modulus of the roots for E. nutans planted in sunny slopes are significantly larger than those in CK groups and shady slopes. And the indices of the roots for E. nutans planted in sunny slopes have larger values in root diameter and tensile resistance but have smaller values in tensile strength, tensile strain at crack than those in CK groups. The results of this study provide theoretical support for the ecological restoration in places of alpine meadow and can also provide reference for the ecological restoration and treatment of regions with similar geological, geographical and climatic conditions of the study area.