摘要
在内蒙古额济纳旗运用微气象学方法以多路传感器同步观测的方式对极端干旱区荒漠河岸林小气候进行了观测。对我国极端干旱区荒漠河岸林胡杨和柽柳群落内的小气候特征与空旷地的差异进行了初步的探讨,并分析了产生这些差异的原因。结果表明:荒漠河岸林具有独特的小气候作用。具有改变太阳辐射、调节近地层地表及地下温度、缩小温差、降低风速、增加土壤湿度和提高空气湿度等重要生态作用。(1)胡杨和柽柳群落均起到了改变太阳辐射的作用,林冠层顶部的太阳总辐射量月平均值分别为341.72MJ.m-2、345.14MJ.m-2,林冠遮蔽使胡杨和柽柳林内总辐射比林外分别减少49.8%、49.3%;(2)生长季胡杨和柽柳林内的气温均低于林外,胡杨林平均比对照低1.62℃,柽柳林平均比对照低0.83℃,而且森林覆盖率越高降温作用越明显;群落上层气温高于群落下层,气温随高度增加而增加;(3)林内平均大气相对湿度均高于林外,胡杨林生长季比对照平均高8.5%,柽柳林平均比对照大4.2%。胡杨林地空气相对湿度各月值高于柽柳林地,平均湿度比柽柳高4.33%;(4)柽柳林月平均土壤温度(19.43℃)高于胡杨林地(18.20℃);(5)林内风速低于林外,胡杨林地平均风速为0.33m.s-1,比林外降低了2.7m.s-1;柽柳林平均风速为0.72m.s-1,比林外降低了2.31m.s-1。胡杨林比柽柳林对风的阻挡作用强。
Using the micrometeorological method we observed the microclimate in the Populus euphratica and Tamarix ramosissima communities from May to October in the years of 2002 and 2003 in the desert riparian forest of the extreme arid region in northwest China. The difference of microclimate between the Populus euphratica and Tamarix ramosissima communities, as well as their comparison with the hare land was analyzed, The results showed that the desert riparian forest has particular partial climate effect, such as changing the radiation condition of land, adjusting the temperature of land surface and underground, reducing temperature, slowing down wind speed, improving the humidity of soil and air efficiently. （1）Populus euphratica and Tamarix ramosissima communities can change the radiation condition of land because of the canopy cover of Populus euphratica and Tamarix ramosissima, the total radiation in the above two forests are 49.8 % and 49.3 % lower than that in the check field, respecfively;（2）The mean temperature in Populus euphratica and Tamarix ramosissima communities are 1.62℃ and 0. 83℃, which is lower than that in the check field, the higher of the cover rate, the more significant of the effect of lowering temperature. With the height decreases, the air temperature decreases gradually in growing season. （3）The mean relative humidity in Populus euphratica and Tamarix ramosissima forests are 37.5% and 33.2%, respectively, which is higher than that in the check field （8. 5% and 4. 2%, respectively）. （4）The soil temperature in Populus euphratica community （18.2℃）is lower than that in Tarnarix ramosissima （19. 43℃）. With the height decreases, the soil temperature gradually decreases both in Populus euphratica and Tamarix ramosissima communities. （5）Wind speed in communities is lower than that over hare land, the mean wind speed in Populus euphratica and Tamarix ramosissima communities are 0.33 m·s^-1 and 0. 72 m·s^-1, respectively.
出处
《中国沙漠》
CSCD
北大核心
2005年第5期668-674,共7页
Journal of Desert Research
基金
中国科学院"引进杰出人才"课题(2003401)
中国科学院知识创新工程项目(KZCX1-09-03)
国家重点基础研究发展规划项目(G199904230601)共同资助
关键词
极端干旱区
荒漠河岸林
胡杨
柽柳
小气候
extreme arid region
desert riparian forest
Populus euphratica
Tarnarix ramosissima
microclimate
