摘要
在西藏拉萨测量了藏冬系列3个冬小麦品种的冠层几何结构及冠层对光合有效辐射(PAR)的反射率、透过率和截获率。通过实测和理论计算,结果表明:高原地区冬小麦叶片比平原地区的更趋于直立,具有比平原地区低的消光系数,能够容纳较大的绿叶面积和有效穗数;当冠层对PAR的截获率趋于饱和时,高原地区麦田可容纳的最大绿叶面积可达8.6,是平原地区的1.4倍左右;开花到成熟期间的叶日积(LAD)大约可达平原地区的2倍,绿叶面积持续时间长;整个生长季期间,高原地区的PAR总量是平原地区的1.7倍,单位绿叶面积所截获的PAR是平原地区的1.3倍,又由于其叶片的趋于直立,故从上到下叶片受光比平原地区更均匀和充分,群体光合潜力高,对PAR的利用率更高。这些因素是高原冬小麦高产的重要原因。
Three winter wheat varieties were planted in Tibet Plateau.The geometry of canopy and interception of photosynthetically active radiation(PAR) were measured.Effects of those factors on grain yield were discussed.The results,from a theoretical analysis and field measurements,indicate that,in Tibet Plateau,leaves of winter wheat were erect while those in plain regions not so.From flowering to harvest time,the leaf area duration (LAD) of Plateau field was about 2 times of that of plain field.In growing season,when the interception of PAR tended to satuaration,the maximum green leaf area which field could accommodate was about 8.6,1.4 times of that in plain regions.During growing period,the amount of PAR captured by unit green leaf area was 1.3 times of that in plain regions.PAR distributed vertically in the canopy was more even and sufficient than that in plain regions.
出处
《生态学报》
CAS
CSCD
北大核心
1998年第4期392-398,共7页
Acta Ecologica Sinica
基金
国家自然科学基金
关键词
青藏高原
冬小麦
冠层几何结构
光截获
消光系数
Tibet Plateau,winter wheat,geometry of canopy,interception of PAR extenuation coefficient(K),leaf area duration(LAD)