关键词：
民勤县;绿洲;固沙林;土壤保护;防风固沙
摘 要：
在民勤绿洲边缘,以林龄为30a左右的柽柳林、白刺林和不同林龄的梭梭林为研究对象,测定和分析固沙林的防风固沙效应。结果表明,固沙林的防风固沙效应取决于树种类型及树龄,且保护效应在迎风面和背风面差异显著。不同树种固沙林降低风沙流流量和减少风蚀深度的效应均表现为30年生梭梭林>柽柳林>40年生梭梭林>20年生梭梭林>白刺>裸沙地,且随着梭梭林龄的增长,30a林龄时达到最大;各固沙林地背风面地表粗糙度变化范围在0.57~4.18cm,以30年生梭梭林最大,白刺最小,且均大于裸沙地,背风面距离林木越远,地表粗糙度逐渐减小;梭梭林背风面各测点的风积厚度、风速降低幅度和地表粗糙度的均值随着林龄的增长分别由0.21cm、12.66%、2.25cm增大到0.5cm、20.41%、3.38cm;植株的高度对防风效果有显著影响,越接近固沙林中部,对风速的影响越大,林木背风面中部的风速降低幅度是顶端处的1.16~3.99倍。梭梭林与其他固沙林相比防风固沙效果明显,是当地值得推广种植的防风固沙树种。
译 名：
Windbreak Effect of Sand-Fixation Forest on the Edge of Oasis in Minqin
作 者：
WANG Yan-wu;LUO Ling;ZHANG Feng;CHEN Tian-lin;Gansu Institute of Soil and Water Conservation Sciences;College of Resource and Environment,Henan Polytechnic University;Soil and Water Conservation Bureau,Department of Water Resources of Gansu Province;
单 位：
WANG Yan-wu%LUO Ling%ZHANG Feng%CHEN Tian-lin%Gansu Institute of Soil and Water Conservation Sciences%College of Resource and Environment,Henan Polytechnic University%Soil and Water Conservation Bureau,Department of Water Resources of Gansu Province
关键词：
Minqin County;;oasis;;sand-fixation forest;;soil conservation;;windbreak and sand fixation
摘 要：
The stands of about 30 years of Tamarix,Nitraria and the different ages of Haloxylonforests were studied to determine and analyze the windbreak and sand-fixation effects at the edge of Minqin Oasis.The results showed that the windbreak and sand fixation effects of sand fixation depended on the type and age of the tree species.The protective effect had significant difference between windward and leeward.Effects of different tree species on reducing the wind-sand flow rate and wind erosion depth were in the order of 30-year-old Haloxylon>Tamarix>40-year-old Haloxylonforest>20-year-old Haloxylonforest>Nitraria>bare sandy land.Haloxylon ammodendron reached the maximum effects at the age of 30.The surface roughness of sand fixing forest leeward changed in the range of 0.57-4.18 cm,30-year-old Haloxylon was the maximum and the smallest was Nitraria,and all of them were larger than those in the bare sand.The surface roughness gradually decreased with the trees farther away the leeward face.The means of wind product thickness,the decreasing amplitude of wind speed and surface roughness of the measured points in the leeward side of Haloxylon were increased from 0.21 cm,12.66%,2.25 cm to 0.5 cm,20.41%and 3.38 cm,respectively.The plant height had a significant impact the windbreak effect.The closer to themiddle of the sand fixing forest,the greater of the impact on the wind speed.The decreasing amplitude of wind speed in the middle of the forest leeward was 1.16-3.99 times lower than the top.Compared to other forests,Haloxylonforest was the best choice to be promoted in Minqin Oasis for its significant windproof effect.
