【作者】 马灿；

【导师】 魏国孝；

【作者基本信息】 兰州大学 ， 水文学及水资源， 2013， 硕士

【摘要】 在农业生产中水是基本要素,农作物通过从土壤中吸收水分经过茎秆运输以进行光合作用并将生成的营养物质进行传输,是农作物进行生产最重要的环节,本文通过运用LI-6400便携式光合仪观测的数据研究玉米叶片光合速率及其影响因子,并运用包裹式热平衡茎流计测定植物的茎流流速、结合自记式气象站观测的同步实时数据以分析研究玉米茎流流速规律和其影响因子,最后运用能量平衡的观点对比同一时段太阳光能、风能的能量值与茎流运输耗费的能量值来分析太阳光照和风与玉米茎流的相关性。得到的研究结果主要有如下几方面：1.玉米在进行光合作用过程中,玉米叶片的净光合速率基本呈单峰型,净光合速率的最大值出现在下午13：00,下午的整体光合速率高于上午,净光合速率的变化对太阳光合辐射有一定程度的“滞后现象”。玉米叶片的净光合速率与气孔导度、胞间二氧化碳浓度、叶片温度和光合有效辐射的相关系数分别为0.916、-0.882、0.899和0.930,光合有效辐射对玉米叶片的净光合速率影响最大。2.玉米茎流在白天和夜晚的数值相差较大,夜晚时段玉米茎流基本停止,间或有小幅度的茎流传输,以补充玉米在白天高强度的蒸腾作用造成的缺少现象。在雨天条件下,玉米茎流流速全天较平稳,这与雨天条件下净太阳光合辐射值较小和气温较低相关。多云条件下由于经光合辐射的大幅度增减,茎流流速也相应出现大幅度波动现象。3.玉米茎流做功与玉米叶片吸收风能间的相关系数为0.533,两者间的回归方程为Y=1695273+162.03X+5E-0.006X2+6.424E-8X3,拟合度R2为0.348。玉米茎流做功与玉米叶片吸收太阳能间的相关系数为0.948,两者间的回归方程为Y=-318197.7+1.237X-1.344E-7X2+6.494E-15X3,拟合度R2为0.928。4.太阳能不仅直接为玉米叶片细胞间水分的水汽转化提供能量,还通过改变玉米自身和生长环境的条件如提高叶片温度、降低空气湿度等,间接促进玉米蒸腾作用加速。风主要通过吹走叶片附近水汽含量较高的空气进而间接促进玉米蒸腾作用,且风不具有持续性。所以太阳能是玉米蒸腾作用的主要能量来源,风能对玉米蒸腾作用起一定程度的辅助加速作用。更多还原

【Abstract】 Water is the basic element of agricultural production, corn transport water which was absorbed from soil, and transport resulting nutrients which was produted through photosynthesis, is the most important part of agricultural production.This paper research the photosynthetic rate and its impact factor on maize through the data been observed by LI-6400Portable Photosynthesis system, employing heat balance Dynamax packaged sap flow measuring system observe the sap flow of maize, combining the synchronize data of self-recording weather stations to study the discipiline of corn sap flow and its impact factor. Finally, on account of energy balance principle analysing the correlation between solar, wind energy and corn sap flow by comparing the the amount of solar、wind energy and the amount of corn sap flow.The main results were as followed:1.During the process of corn photosynthesis, the basic corn leaf net photosynthetic rate showed a single peak, net maximum photosynthetic rate appeared in13:00, the total photosynthetic rate of afternoon was higher than the morning, compare with the rate of photosynthetic solar radiation, net photosynthetic rate has a certain degree of "hysteresis". The correlation coefficient between Com leaf net photosynthetic rate and stomatal conductance、 intercellular CO2concentration、leaf temperature and photosynthetic active radiation were0.916,-0.882,0.899and0.930, photosynthetically active radiation has the greatest impact on net photosynthetic rate of maize leaves.2. There have a large difference in maize sap flow between day and night,maize sap flow basically stopped in night,but had slight sapflow,this phenomenon can supply water for waize which have high velocity transpiration in day. In rainy conditions,the maize sap flow velocity was smooth and steady all day long,the reason was that the net solar radiation and air temperature was relatively low.In cloudy conditions,the maize sap flow had significantly wave because of the lower net solar radiation.3. The correlation coefficient between maize sap flow work and wind energy which was absorbed by maize leaves was0.533,the regression equation between the two was Y=1695273+162.03X+5E-0.006X2+6.424E-8X3,and the fitting degree R2was0.348. The correlation coefficient between maize sap flow work and solar energy which was absorbed by maize leaves was0.948,the regression equation between the two was Y=-318197.7+1.237X-1.344E-7X2+6.494E-15X3,and the fitting degree R2was0.928.4. Solar energy not only supply energy for water vapor transfer in maize leaf intercellular,but also change the condition of maize itself and grow environment,for example, raised the temperature of maize leaves、reduced air humidity, this could speed up the transpiration of maize.Wind could speed up maize transpiration through flowed air away which had higher levels of vapor, but wind was not continued. Solar energy was main energy source of maize transpiration, wind energy had a certain degree acceleration to maize transpiration.更多还原