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作 者:冯泽深[1] 高甲荣[1] 赵哲光[1] 贺康宁[1] 李柏[1]
机构地区:[1]北京林业大学教育部水土保持与荒漠化防治重点实验室,北京100083
出 处:《干旱地区农业研究》2010年第4期269-274,共6页Agricultural Research in the Arid Areas
基 金:国际科技合作项目(2008DFA32270);国家自然科学基金资助项目(40771128)
摘 要:测定研究了3种不同配置格局沙柳林的风速廓线梯度,得出行带式配置防风效果最好,均匀式次之,随机式最差。通过实地观测近地表输沙率和地表粗糙度,计算行带式配置中不同规格沙柳林的防护成本效益。结果表明:一行一带、带高1.5 m、带距7.5 m、插深0.5 m配置规格的行带式沙柳林防护成本效益最好,但限于15倍带高以内;行数一定的情况下,防护林带越高,防护成本效益越大。Wind velocity profile gradients of three spatial arrangement patterns of Salix psammophila were measured.The results show that belt shrub community has the best windbreak effect,while the random has the poorest one.Near ground sand transporting rate and roughness of ground surface of shelterbelts were observed and benefit/cost for windbreak with different rows of salix psammophila belts were calculated.It is found out that spatial pattern of one-row belts,1.5 m in height,7.5 m in belt distance and 0.5 m in depth have the highest defending benefits.When with the same rows,the higher the plants are,the better are their defending benefits.
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