【摘要】 各树种在年生长季不同测期的蒸腾速率日进程曲线一般呈单峰型。蒸腾速率与环境因子的相关性大小依次为 :光照强度、气温、相对湿度和大气水势。蒸腾速率日变化一般可用具有光照因子的优化模型 (即光照型、光温型、光湿型和光温湿型 )来模拟。年生长季树种蒸腾速率 ( g· g- 1L D· h- 1)排序由大到小为 :柠条 ( 0 .92 69± 0 .2 0 89) (平均值±标准差 ,以下同 )、小叶杨 ( 0 .71 77± 0 .2 4 1 0 )、河北杨( 0 .62 56± 0 .1 60 9)和北京杨 ( 0 .60 0 7± 0 .2 749) ;净光合速率 ( mg CO2 · g- 1LD· h- 1)排序自高至低为 :柠条 ( 1 4.5949± 4.662 7)、小叶杨 ( 1 3.40 55± 2 .9994)、河北杨 ( 1 3.2 569± 4.3531 )和北京杨 ( 1 1 .6989± 2 .5884) ;蒸腾效率 ( g DM· g- 1H2 O)排序由高至低为 :北京杨 ( 1 .41 %± 0 .42 % )、河北杨 ( 1 .35%± 0 .36% )、小叶杨 ( 1 .2 6%± 0 .2 3% )和柠条 ( 1 .0 0 %± 0 .2 7% )更多还原

【Abstract】 The diurnal course of transpiration rate generally showed a pattern of single peak and had a close relationship with L i(light intensity) in the species: P.hopeiensis, P. simonii,P. beijingensis and C.korshinskii . The four sorts of optimal models of transpiration rate consisted of the independent variable of L i; the independant variables of L i and T(temperature),the independant variables of L i and RH(relative humidity),and the independant variables of L i, T and RH, respectively. These four species had the transpiration rates (g·g -1 LD·h -1 ) in the following order: C.korshinskii (0 9269±0 2089)(mean±1SD)> P. simonii (0 7177±0 2410)> P. hopeiensis (0 6256±0 1609)> P. beijingensis (0 6007±0 2749); the net photosynthesis rate (mgCO 2·g -1 LD·h -1 ) was C. korshinskii (14 5949±4 6627)> P.simonii (13 4055±2 9994)> P.hopeiensis (13 2569±4 3531)> P. beijingensis (11 6989±2 5884); and the transpiration efficiency (gDM·g -1 H 2O) was P. beijingensis (1 41%±0 42%)> P. hopeiensis (1 35%±0 36%)> P. simonii (1 26%±0 23%)> C.korshinskii (1 00%±0 27%).更多还原