樟子松(Pinus sylvestnis var. mongolica)是中国北方沙区推广面积最大的常绿乔木树种之一。为了解其幼苗对持续风吹的光合生理响应,2013年春季在内蒙古科尔沁沙地研究了0(CK)、6、9、12、15、18 m·s-1等梯度风速1 h持续吹袭下3龄樟子松幼苗光合速率(Pn)、蒸腾速率(Tr)、水分利用效率(WUE)、气孔导度(Gs)和胞间CO2浓度(Ci)等指标的变化。结果表明:(1)随着风速的增强,其叶片温度和相对含水量趋于下降,和CK相比,18 m·s-1处理的叶片温度和相对含水量分别下降1.6%和2.9%;(2)和CK一样,不同风速处理下其Pn、Tr和WUE的日变化均为单峰曲线,Gs呈下滑曲线,Ci浓度呈V形曲线,显示风吹强度的增加没有改变樟子松幼苗的光合特征的日变化规律;(3)低风速(6~9 m·s-1)持续风吹导致其日均Pn、Tr、Gs降低,但日均Ci和WUE变化不显著;(4)高风速(12~18 m·s-1)下,除18 m·s-1处理Gs下降外,其日均Pn、Tr、Gs、Ci均趋于增加,但WUE下降;(5)高风速风吹下,Gs和Ci的增加是其Pn、Tr增加的主要原因,低风速风吹下其Pn和Tr的降低也源于Gs和Ci的下降。
In order to understand responses of photosynthesis and water metabolism of Pinus sylvestnis var. mongolica seedlings to continuous wind blowing, a wind tunnel experiment with a wind speed gradient wind of 0 (CK)、6、9、12、15 and 18 m·s-1 was conducted in the Horqin Sandy Land in Spring, 2013. The results showed that the leaf temperature and leaf relative water contents tended to decrease with increase of wind speed, which decreased by 1.6% and 2.9% in the 18 m·s-1 treatment than the CK, respectively. (2)in the different treatments, diurnal changes of the photosynthetic rate, transpiration rate and water use efficiency represented as single peak curve, change of the stomatal conductance was downward curve, change of the intercellular CO2 concentration was a V curve, which suggested that changes of the wind speed didn't altered the diurnal regular patterns in these properties. (3)the lower wind speed (6-9 m·s-1) resulted in decrease of the peak value and diurnal average value of photosynthetic rate and stomatal conductance, increase of the water use efficiency, but a not significant change of the peak value and diurnal average value of the intercellular CO2 concentration. (4)in the higher wind speed treatments (12-18 m·s-1), the peak values and diurnal average values of the photosynthetic rate and transpiration rate increased, water use efficiency decreased, the decreased magnitude of the stomatal conductance was greater compared to the lower wind speed; (5)At the high wind speed, the increase of photosynthetic rate and transpiration rate was mainly attributed to increase of stomatal conductance and intercellular CO2 concentration, decrease of photosynthetic rate and transpiration rate at the lower wind resulted mainly from decrease of stomatal conductance and intercellular CO2 concentration.
[1] 赵哈林.沙漠生态学[M].北京:科学出版社,2013.
[2] 于云江,辛越勇,刘家琼.风和风沙流对不同固沙植物生理状况的影响[J].植物学报,1986,40(10):962-968.
[3] 赵哈林,何玉惠,岳广阳,等.风吹沙埋对沙地植物幼苗生长和光合蒸腾特性的影响及响应机制[J].生态学杂志,2010,29(3):413-419.
[4] Ashby W C,Kolar C A,Hendricks T R,et al.Effects of shaking and shading on growth of three hardwood species[J].Forest Science,1979,25(2):212-216.
[5] Biddington N L,Dearman A S.The effects of mechanically-induced stress and plant growth regulators on the growth of lettuce,cauliflower and bean (Phaseolus vulgaris L.) plants[J].Plant Growth Regulation,1987,5(3):183-194.
[6] Ennos A R.Wind as an ecological factor[J].Trends in Ecology & Evolution,1997,12(3):108-111.
[7] Braam J.In touch:plant responses to mechanical stimuli[J].New Phytologist,2005,165(3):373-389.
[8] Grace J,Malcolm D C,Bradbury I K.The effect of wind and humidity on leaf diffusive resistance in Sitka spruce seedlings[J].Journal of Applied Ecology,1975,12(3):931-940.
[9] Henry H A L,Thomas S C.Interactive effects of lateral shade and wind on stem allometry,biomass allocation,and mechanical stability in Abutilon theophrasti (Malvaceae)[J].American Journal of Botany,2002,89(10):1609-1615.
[10] Knight M R,Smith S M,Trewavas A J.Wind-induced plantmotion immediately increases cytosolic calcium[J].Proceedings of the National Academy of Sciences of the United States of America,1992,89(11):4967-4971.
[11] Braam J,Davis R W.Rain-,wind-,and touch-induced expression of calmodulin and calmodulin-related genes in Arabidopsis[J].Cell,1990,60(3):357-364.
[12] 王艳红,何维明,于飞海,等.植物响应对风致机械刺激研究进展[J].生态学报,2010,30(3):794-800.
[13] 曲浩,赵学勇,岳广阳,等.科尔沁沙地几种常见植物对风胁迫的生理响应[J].中国沙漠,2009,29(4):668-673.
[14] 赵兴梁,李万英.樟子松[M].北京:农业出版社,1961.
[15] 李宏印,刘明国.樟子松人工固沙林发展现状[J].辽宁林业科技,2003(5):35-39.
[16] 焦树仁.樟子松沙地造林技术综述[J].防护林科技,2010(6):52-54.
[17] 孟鹏,李玉灵,尤国春,等.彰武松、樟子松光合生产与蒸腾耗水特性[J].生态学报,2012,32(10):3050-3060.
[18] 陈根云,陈娟,许大全.关于净光合速率和胞间CO2浓度关系的思考[J].植物生理学通讯,2010,46(1):64-66.
[19] Mitchell C A.Recent advances in plant response to mechanical stress:theory and application[J].Hortscience,1996,31(1):31-35.
[20] Russell G,Grace J.The effect of wind on grass v.Leaf extension,diffusive conductance,and photosynthesis in the wind tunnel[J].Journal of Experimental Botany,1978,29(5):1249-1258.
[21] 赵文智,常学礼.樟子松针叶气孔运动与蒸腾强度关系研究[J].中国沙漠,1995,15(3):241-243.
[22] 朱教君,康宏樟,李智辉,等.水分胁迫对不同年龄沙地樟子松幼苗存活与光合特性影响[J].生态学报,2005,25(10):2527-2533.
[23] Whitehead F H.Experimental studies on the effect of wind on plant growth and development:Helianthus annuus[J].New Phytologist,1962,61(1):59-62.
[24] Telewski F W,Jaffe M J.Thigmom ophogenesis:Field and laboratory studies of Abies fraseri in response to wind or mechanical perturbation[J].Physiologia Plantarum,1986,66(2):211-218.
[25] Wang Y H,He W M,Dong M,et al.Effects of shaking on the growth and mechanical properties of Hedysarum laeve may be independent of water regimes[J].International Journal of Plant Sciences,2008,169(4):503-508.