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黄土丘陵区3个树种光合效率光响应过程及其模拟

Light Response and Simulation of the Photosynthetic Efficiency on Three Tree Species in the Loss Hilly Region

作者: 专业:水土保持与荒漠化防治 导师:张光灿 年度:2010 学位:硕士  院校: 山东农业大学

Keywords

Soil water stress, Three tree species, Photosynthesis, Traspiration, Light response model

        半干旱黄土丘陵区是我国典型的生态脆弱地区,而水分是制约植被恢复与重建的主要因素。本文针对半干旱黄土丘陵区干旱缺水的主要特征,在山西省吕梁山西麓的方山县峪口镇土桥沟流域,以山杏(Prunus armeniaca)、沙棘(Hippophae rhamnoides)和油松(Pinus tabulaeformis)三种树种作为试验材料,布设盆栽试验及大田试验。通过对不同土壤湿度下各个树种光合作用效率指标光响应过程的观测,阐明在正常水分环境条件下,三个树种叶片光合作用、蒸腾作用和水分利用等生理过程的基本特征,及其在土壤水分胁迫环境下的变化特征与机制;并揭示在模拟光辐射增强过程中,三个树种光合作用效率(净光合速率、蒸腾速率、水分利用效率等)的变化特征与机理。在此基础上,探索三个树种光合作用对水分和光照的适应性特征,明确维持其较高光合作用效率的适宜土壤湿度范围(包括土壤水分最低、最适、最高临界值)。为三个树种在黄土丘陵区造林中适宜的立地配置提供理论与技术依据。1、三个树种光合作用效率对土壤湿度的响应特征(1)三个树种叶片气体交换参数对土壤水分具有明显的阈值响应根据光合速率、蒸腾速率等气体交换参数与土壤水分关系的分析结果,初步确定了三个树种以提高光合生产力与水分利用效率为核心的适宜土壤水分条件、植物水分最大亏缺及适宜的光强范围。盆栽沙棘、盆栽山杏、大田山杏、盆栽油松和大田油松生长适宜的土壤水分范围分别为:38.49%~71.69%、44.70%~68.20%、34.20%~62.31%、35.72%~68.50%、34.71%~68.95%。盆栽沙棘、盆栽山杏、大田山杏、盆栽油松和大田油松生长的土壤水分最大亏缺分别为:30.00%、28.33%、30.50%、27.61%、28.10%。油松、山杏和沙棘生长的适宜的光照强度范围分别为:300~1300μmol·m-2·s-1、500~1300μmol·m-2·s-1、500~1400μmol·m-2·s-1。(2)三个树种的光合量子效率、最大光合速率、光饱和点和暗呼吸速率等光合效率参数受土壤水分的影响显著,对RWC具有明显的阈值响应。三个树种的光合量子效率(Φ)、最大光合速率(Pnmax)、光饱和点(LSP)、暗呼吸速率(Rd)和光补偿点(LCP)等光合效率参数对土壤水分的变化具有明显的阈值响应过程。随着土壤湿度的由低到高的变化,Φ、Pnmax、LSP和Rd都表现为先增大后减小的过程,而LCP表现为先减小后增大的过程。但不同树种的光合效率参数发生转折变化的土壤湿度临界值有所不同。三个树种对弱光的利用能力由高到低的顺序为:大田山杏、盆栽沙棘、盆栽山杏、盆栽油松、大田油松。不同树种对光合产物的消耗也表现出较大的差异,由多到少的顺序为:沙棘、山杏、油松。2、三个树种光合作用效率对光照强度的响应特征对三个树种光适应的分析,其光照强度的上、下限是根据维持较高Pn的PAR来选择的,对其最适光照强度是根据维持最高Pn的LSP来确定的。维持三个树种较高Pn的最低光照强度差别较小。油松的光照强度最低在300μmol·m-2·s-1左右;山杏和沙棘的最低光强大约在500μmol·m-2·s-1左右。表明油松忍受弱光的能力明显高于其它树种,在弱光下仍具有较高的Pn。维持三个树种最高Pn的最适光照强度变动幅度较小。维持三个树种较高Pn的最高光强没有明显差异,三个树种均能在较高的光强下维持较高的Pn,表现出对光环境较高的适应能力。沙棘的最高光强为1400μmol·m-2·s-1,油松的在1500μmol·m-2·s-1左右,山杏的在1600μmol·m-2·s-1左右。油松、山杏和沙棘生长的适宜的光照强度范围分别为:300~1300μmol·m-2·s-1、500~1300μmol·m-2·s-1、500~1400μmol·m-2·s-1。3、三个树种光合作用光响应过程的适宜模型利用三个经验模型(直角双曲线模型、非直角双曲线模型和直角双曲线修正模型)对三个树种光合作用光响应过程的模拟结果表明,非直角双曲线模型拟合的总体效果要好于直角双曲线模型。而直角双曲线修正模型能很好的解决直角双曲线模型和非直角双曲线模型的缺点,可以直接计算植物的饱和光强和最大净光合速率。求解的光合量子效率(Φ)、最大光合速率(Pnmax)、光补偿点(LCP)和暗呼吸速率(Rd)最接近实测值。而且直角双曲线修正模型不但可以拟合植物在饱和光强之后光合速率不下降的光响应曲线,而且还可以拟合植物在饱和光强之后光合速率随光强的增加而下降这一段的光响应曲线,且估算的饱和光强和最大净光合速率与实测值最为接近。
    The semi-arid hill area of Loess Plateau is the typical fragile area in our country. In this region, moisture is the key factor to limit the vegetation restoration and reconstruction. Because semi-arid hill area of Loess Plateau is scarce of water resource, three tree species of Prunus armeniaca, Hippophae rhamnoides, and Pinus tabulaeformis, are chosen as experimental material to carry out pot experiment and field experiment in Tuqiaogou valley, Yukou town, Fangshan county, Lvliang city, Shanxi province.Through different soil humidity on the three kinds of photosynthesis efficiency indicator light response of the observation, we clarified the basic features of physiological processes of the three kinds of leaf photosynthesis, transpiration and water use etc. under normal growth conditions;revealed in the simulation of light radiation process, photosynthesis efficiency (net photosynthetic rate, transpiration rate, etc.) changes in characteristics and mechanisms; confirmed the fitting soil moisture range mainting higher photosynthesis rate (including minimum, optimum, maximum critical soil moisture); and also elucidate the light adaptation characteristics of plant photosynthesis.The results have the practical meaning of scientific directing the reasonable tree choice, habitats collocating in semi-arid Loess Hilly region. The main results are as follows:1.Define the photosynthetic efficiency of three species response characteristics to soil moisture(1)The gas exchange parameters of three trees have notable threshold response value to soil moisture.According to the relationship between gas exchange parameters, such as photosynthesis rate (Pn), transpiration rate (Tr) etc., and soil moisture, the suitable soil moisture, most wane of soil moisture and suitable photosynthetic active radiation (PAR) were confirmed elementary to increase Pn and WUE. The range of relative water content (RWC) being suitable for the growth of bonsai Hippophae rhamnoides subsp sinensis, bonsai Prunus armeniaca var.ansu, field Prunus armeniaca var.ansu, bonsai Pinus tabulaeformis and field Pinus tabulaeformis was: 38.49%~71.69%,44.70%~68.20%,34.20%~62.31%,35.72%~68.50%,34.71%~68.95%.And the most wane of soil moisture deficit was: 30.00%、28.33%、30.50%、27.61%、28.10%. The range of most suitable PAR being suitable for the growth of Pinus tabulaeformis, Hippophae rhamnoides subsp sinensis, Prunus armeniaca var.ansu was: 300~1300μmol·m-2·s-1、500~1300μmol·m-2·s-1、500~1400μmol·m-2·s-1.(2) The apparent quantum yield (Φ), Maximum photosynthetic rate (Pnmax) , Light saturation point (LSP) and dark respiration rate (Rd) was affected by soil moisture apparently and had notable threshold response to RWC.The photosynthetic efficiency parameters of apparent quantum yield (Φ), maximum photosynthetic rate (Pnmax), light saturation point (LSP), dark respiration rate (Rd) and light compensation points (LCP) atc.had notable threshold response to RWC. As the soil moisture changes from low to high,Φ, Pnmax, LSP and Rd increased gradually and reached to the maximal value and then fell gradually. But LCP fell at first then increased gradually. However, different species of photosynthetic efficiency parameter changes the shift in different soil moisture threshold. According to the utilization of low light intensity, the sequence was field Prunus armeniaca var.ansu, bonsai Hippophae rhamnoides subsp sinensis, bonsai Prunus armeniaca var.ansu, bonsai Pinus tabulaeformis and field Pinus tabulaeformis. According to the consume photosynthesis production, the sequence was Hippophae rhamnoides, Prunus armeniaca, Pinus tabulaeformis.2. Identified the photosynthetic efficiency of three trees on the response characteristics of light intensityThrough the analysis of three species of light adaptation, the light intensity of upper and lower limit is based on the PAR to maintain higher Pn options, and its optimum light intensity is based on the LSP to maintain the highest Pn to determine.The difference between minimum light intensity to maintain higher Pn of three species is small. The minimum light intensity of Pinus tabulaeformis was 300μmol·m-2·s-1, Prunus armeniaca and Hippophae rhamnoides were 500μmol·m-2·s-1. It can be seen that the capacity of Pinus tabulaeformis tolerate low light are better than the other species, it has a higher Pn in low light. The optimum light intensity has a smaller rate of change to maintain the highest Pn.Three species has no significant difference in light intensity to maintain a higher maximum Pn, its can be maintained the higher Pn at a higher light intensity, and showed a higher ability to adapt to light environments. The maximum intensity of Hippophae rhamnoides was 1400μmol·m-2·s-1, Pinus tabulaeformis was 1500μmol·m-2·s-1, and Prunus armeniaca was 1600μmol·m-2·s-1.The range of light intensity being suitable for the growth were 300~1300μmol·m-2·s-1, 500~1300μmol·m-2·s-1, 500~1400μmol·m-2·s-1.3.The fitting models of three species photosynthetic light response were confirmed.Contrasted between three empirical models we found that the fitting effects of photosynthesis response curve with non-rectangle hyperbolae model was better than rectangle hyperbolae model. The rectangular hyperbolic model can be a good solution the shortcomings of modified rectangular hyperbolic model and non-rectangular hyperbolic mode, can directly calculate the saturation intensity and maximum net photosynthetic rate, and the photosynthetic quantum efficiency (Φ), maximum photosynthetic rate (Pnmax), light compensation point (LCP) and dark respiration rate (Rd) it solved were the closest to the measured value. And Correction rectangular hyperbola model can not only fit the light response curve that photosynthetic rate does not decrease after the saturation intensity, but also fit the light response curves of this section that photosynthetic rate increased with light intensity dropped after the saturation intensity. And the saturation intensity and maximum net photosynthetic rate it estimates is most close to the measured.
        

黄土丘陵区3个树种光合效率光响应过程及其模拟

符号说明4-7
中文摘要7-10
ABSTRACT10-13
1 引言14-32
    1.1 研究目的与意义14-16
    1.2 研究进展与现状16-32
        1.2.1 植物光合生理生态学的研究进展16-19
        1.2.2 环境因子对植物生理生态特性的影响19-32
            1.2.2.1 环境因子对植物光合作用的影响19-25
            1.2.2.2 环境因子对植物蒸腾耗水特性的影响25-27
            1.2.2.3 环境因子对植物水分利用效率的影响27-30
            1.2.2.4 环境因子对气孔的影响30-32
2 材料与方法32-38
    2.1 试验地自然概况32-33
    2.2 试验材料33-34
    2.3 试验方法34-38
        2.3.1 试验布设与重复设计34
        2.3.2 土壤水分梯度处理与观测34-35
        2.3.3 光合效率指标观测与计算35-36
        2.3.4 数据统计及过程与机制分析36-38
3 结果与分析38-50
    3.1 不同土壤湿度下三个树种光合作用效率的光响应过程与机制38-45
        3.1.1 净光合速率的光响应38-43
        3.1.2 光合速率的光响应参数43-45
    3.2 三个树种光合作用光响应过程模型45-50
        3.2.1 直角双曲线模型45-47
        3.2.2 非直角双曲线模型47-48
        3.2.3 直角双曲线修正模型48-50
4 讨论50-59
    4.1 三个树种的光合-光响应参数52-57
        4.1.1 表观量子效率52-53
        4.1.2 暗呼吸速率53-54
        4.1.3 光补偿点和光饱和点54-57
    4.2 三个树种光合作用的光适应性57-58
    4.3 几个模型存在的问题与展望58-59
5 结论59-68
    5.1 植物叶片气体交换参数对土壤水分和光强具有明显的阈值响应59-60
    5.2 三个树种光合作用光响应过程的模拟及其适宜的模型60-68
参考文献68-83
致谢83-84
攻读学位期间发表论文情况84
        下载全文需84


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