不同土壤水势条件下冬小麦气孔导度的动态变化研究

论文总字数：14869字

目 录

1 绪论………………………………………………………………… 5

1.1研究目的与意义……………………………………………………………………… 5

1.2国内外研究现状……………………………………………………………………… 5

2 材料与方法………………………………………………………… 6

2.1实验设计……………………………………………………………………………… 6

2.2指标测定……………………………………………………………………………… 6

2.3数据处理……………………………………………………………………………… 6

3 不同土壤水势下冬小麦气孔导度的动态变化…………………… 7

3.1不同处理下土壤水势变化趋势……………………………………………………… 7

3.2不同土壤水势对冬小麦生育期的影响……………………………………………… 7

3.3冬小麦气孔导度日变化……………………………………………………………… 8

3.4两典型日气象条件变化情况分析…………………………………………………… 9

3.4.1典型日温度变化分析 ……………………………………………………… 9

3.4.2典型日相对湿度变化分析…………………………………………………… 10

3.4.3典型日光合有效辐射变化分析……………………………………………… 10

3.4.4典型日风速变化分析 ……………………………………………………… 11

4 基于气孔导度模型的气孔导度动态变化……………………… 12

4.1气孔导度模型……………………………………………………………………… 12

4.2环境胁迫系数的变化特征………………………………………………………… 14

4.3气孔导度的模拟…………………………………………………………………… 15

4.3.1气孔导度日变化模拟……………………………………………………… 15

4.3.2气孔导度季节变化模拟…………………………………………………… 16

5 结论……………………………………………………………… 16

6 讨论……………………………………………………………… 17

参考文献……………………………………………………………… 18

致谢…………………………………………………………………… 20

不同土壤水势下冬小麦气孔导度的动态变化研究

边晨昱

，China

Abstract：The trend of aridity under the background of global warming is even more pronounced, and the drought-reduced crop production has caused a huge loss to our economy. Stomata, as an exchange channel between plants and the external environment, plays a critical role in the transpiration, photosynthesis and respiration of crops. In this paper, we set up three treatments: Drought (DR), natural precipitation (NP), natural precipitation and irrigation (NPI). In the meanwhile, the soil water potential and stomatal conductance under different treatments were continuously monitored to evaluate the effects of different soil water potentials on the stomatal conductance of winter wheat. Using the modified Jarvis model to simulate the stomatal conductance with daily and seasonal changes, in order to evaluate the effect of different soil water potentials on the stomatal conductance of winter wheat. The experimental results show that the difference in growth period caused by different treatments is mainly manifested after the flowering stage of wheat. Compared with the control group, the growth period in the arid area is obviously advanced and the growth period in the irrigation period is significantly delayed. The longer the processing, the more obvious the differences in different treatments. The simulation results are consistent with the actual measurement results, but the maximum value of the simulation results is obviously smaller than the actual measurement value, and the minimum value of the simulation results is also significantly smaller than the minimum value of the actual measurement results. It may be related to the setting of the model parameter gmax. The model may overestimate the influence of soil water potential on stomatal conductance. In general, the stomatal conductance under three treatments is: Gs (NPI) gt; Gs (NP) gt; Gs (DR).

Key words：winter wheat; soil water potential; stomatal conductance; Jarvis model;

1. 绪论
   1. 研究目的与意义

气孔是存在于叶表面的微孔，是允许气态物质穿透或离开植物组织的器官。植物通过控制气孔的数量调节其生理功能 ^[1]。光照，温度，湿度，土壤含水量，CO2和空气污染物浓度等环境条件直接或间接地影响气孔调节。液态水蒸发使用热量，所以会导致冷却，如果气孔更加开放，更多的水分蒸发，将导致温度降低^[2]。因此植物通过打开气孔来降低叶片温度以防止由于吸收太阳光而使叶片过热，这构成了热调节机制。气孔关闭通常发生在干旱条件下，当胞间CO₂浓度足以达到最佳光合作用时，气孔关闭以节约用水。通过开放气孔来降低叶片温度的需求与通过关闭气孔来减少用水的需求之间的矛盾通常会出现在过度干旱和高温的情况下，在这种情况下，气孔倾向于关闭以节约用水，但热调节被抑制，叶片变得太热，植物会变得紧张，如果情况恶化，可能会导致叶子死亡^[1,3]。

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