银西高铁宁夏段边坡绿植防护中的坡向差异性

Slope Aspect Difference in Slope Green Plant Protection in Ningxia Section of Yinchuan-Xi′an High-speed Railway

研究目的:银西高铁宁夏段线路行经黄土塬区、荒漠区、黄灌区,平均蒸发量为平均降雨量的4.3~9.5倍,土壤贫瘠。在该种严酷的自然条件下,根据光照强度、土壤温湿度、植物生长状况等路堤左右侧的坡向性差异,确定边坡绿植的选种、栽植、维养等关键参数,为有效防止荒漠化发展、阻止风沙上道并完善铁路生态文明建设提供技术支撑。研究结论:(1)银西高铁线路左侧(西向)边坡的光照强度是右侧(东向)边坡的1.28~1.46倍,相应土壤的温湿度分别是1.06~1.13倍、0.93~0.95倍,呈现出明显的坡向差异性;(2)受区域环境及高铁线路坡向差异性的影响,路堤边坡绿植防护中的成活率、密度、盖度等绿植生长指标,在路堤左侧、右侧(西向、东向)的比值分别为0.91~0.96、0.68~0.71、0.31~0.62,出现了相应且明显的差异性;(3)根据路堤边坡绿植防护试验中呈现出的差异性研究结果,建植时选择四翅滨藜、柠条等耐寒、耐碱、耐贫瘠的绿植物种,且在线路西向边坡加强绿植养护工作;(4)本研究成果已应用于银西高铁边坡绿植防护中,并可为干旱与半干旱区线性工程的绿植防护提供技术参考。

Research purposes:The Ningxia section of Yinchuan-Xi’an High-speed Railway passes through the loess tableland,desert area and yellow irrigation area,the evaporation is 4.3 to 9.5 times the amount of rainfall,and the soil is very poor.Under these harsh natural conditions,according to the difference of the slope direction of the left and right sides of the embankment,such as light intensity,soil temperature and humidity,and plant growth,the key parameters of the green plant selection,planting and maintenance can be determined,which can provide technical support for effectively preventing the development of desertification,preventing the passage of sand and improving the construction of ecological civilization of the railway.Research conclusions:(1)The light intensity on the left side slope(westward)of Yinchuan-Xi′an high-speed railway is 1.28 to 1.46 times that on the right side slope(eastward),and the corresponding,the soil temperature and humidity are 1.06 to 1.13 times and 0.93 to 0.95 times,respectively,showing obvious difference in slope direction.(2)Under the influence of the regional environment and the difference of the slope direction of high-speed railway,the ratio of the vegetation growth indexes such as the survival rate,density and coverage in the protection of the embankment slope are 0.91 to 0.96,0.68 to 0.71 and 0.31 to 0.62 respectively on the left side and the right side(westward and eastward)of the embankment,showing corresponding and obvious differences.(3)According to the difference research results of the plant protection tests on embankment slope,the cold,alkali and barren resistant green plant species such as Atriplex canescenes and Caragana,are suggested to choose for the construction,and the conservation of green plant is strengthened on the west side slope of embankment.(4)The research results are directly applied to the green plant protection on slope of Yinchuan-Xi′an high-speed railway,and provide technical reference for the linear engineering in arid and semi-arid areas.