【作者】 夏江宝；

【导师】 张光灿；

【作者基本信息】 山东农业大学 ， 森林培育学， 2007， 博士

【摘要】 近年来,随着全球性生态环境问题的加剧,恢复和重建植被生态功能已成为人们关心的生态学热点问题之一,光因子胁迫、干旱缺水和大气中CO2浓度不断升高是影响植被分布及生长的重要生态因子。对光合气体交换参数的研究主要集中在农作物和经济林领域,对系列水分梯度下藤本植物的光合生理变化规律研究较少。为此,本文综合应用SPAC界面水分传输理论与植物水分利用效率理论,以五叶地锦(Parthenocissus quinquefolia)、三叶地锦(Parthenocissus semicordata)、大叶扶芳藤(Euonymus fortunei)、小叶扶芳藤(E.f.var.minimus Rhed.)、美国凌霄(Campsis radicans Seen)、蛇葡萄(Ampelopsis brevipedunculata)、紫藤(Wisteria sinensis Sweet)、金银花(Lonicera japonica Thunb)、爬藤卫矛(Euonymus scandens Graham)、常春藤(Hedera neaplensis var. Sinensis)等14种藤本植物幼苗作为试验材料,研究木质藤本植物光合作用效率过程与节水生理机制,确定出主要光合作用效率参数与根-土界面水分含量及叶-气界面光量子通量的定量关系,探索根-土界面水分驱动光合作用的气孔限制机理和叶绿素荧光动力学机制,为干旱瘠薄荒山植被恢复中优良藤本植物选择及其合理的立地配置提供理论与技术依据。获得以下主要研究成果:(1)叶片光合作用效率的光响应过程及其土壤水分驱动效应藤本植物的光合作用、蒸腾作用及水分利用效率与土壤湿度和光照强度密切相关,而且有明显的阈值响应。确定出14种藤本植物正常生长所允许的土壤水分最大亏缺程度、土壤湿度上限值和适宜的土壤湿度范围,以及有利于植物生长和水分高效利用的适宜光合有效辐射强度及上、下限值。其中以紫藤为例说明如下:①维持紫藤正常生长(同时具有较高光合速率(Pn)和水分利用效率(WUE))的土壤湿度范围,在重量含水量(Wm)为13.1%～22.6%、相对含水量(Wr)在46.5%～80.6%之间,最佳土壤湿度在Wm为19.9%(Wr为70.9%)左右。②紫藤对光照环境的适应性较强,在PAR为600～1600μmol·m-2·s-1范围内,Pn和WUE都具有较高水平,饱和光强大约在PAR为800～1000μmol·m-2·s-1。③紫藤正常生长所允许的最低土壤湿度在Wm为10.2%(Wr为36.2%)左右,此时允许的最高PAR在1000μmol·m-2·s-1左右,是紫藤叶片光合机构受到破坏的临界点。④建立藤本植物叶-气界面水分传输效率对辐射强度的响应模型,如美国凌霄采用非直角双曲线模型进行模拟光响应过程较好,光响应曲线曲角接近于1,随着重量含水量Wm (5.5%～19.4%)、相对含水量Wr(20.1%～71.1%)的递增,光补偿点降低,光饱和点、最大净光合速率及表观量子效率均升高,在Wm为19.4%时,达到光补偿点最低(21.61μmol·m-2·s-1),光饱和点最高(1400μmol·m-2·s-1)。⑤随着水分胁迫的加重,光合速率的下降由气孔限制向非气孔限制过渡。如紫藤光合作用非气孔限制的发生与土壤湿度与光照强度密切相关,在Wm为15.7%～22.6%(Wr为56.0%～80.6%)范围内,光合作用主要受气孔限制,受光照强度的影响较小;超出此范围后,受光照强度的影响较大,出现由气孔限制转变为非气孔限制的PAR临界值。(2)叶片光合作用效率的日动态及其对土壤水分胁迫的响应①水分充足条件下,影响藤本植物光合作用的主要因子,可以归纳为两类,一类是大气温度和空气相对湿度,一类是光照强度;在重度水分胁迫条件下,一类是光照强度和大气CO2浓度,一类是空气相对湿度。②在各种水分条件下,金银花品种的光合速率相对较高,特别是鸡抓花和花叶表现明显。在适度的水分胁迫下,爬藤卫矛、蛇葡萄、大叶扶芳藤的光合速率相对也较高;其次光合速率维持较高值的为美国凌霄、小叶扶芳藤、五叶地锦、三叶地锦、紫藤等几种藤本植物。在水分条件相对较好的情况下,与其他藤本植物相比较,紫藤、五叶地锦、常春藤均表现出较低的光合速率值。③随着水分胁迫的加重,多数藤本植物蒸腾速率和水分利用效率表现出下降的趋势,其蒸腾速率的影响因子变化也较为复杂。从单一因子相关性分析和逐步回归方程中的综合影响因子来看,各水分胁迫下,环境因子对美国凌霄水分利用效率的影响较为复杂,多为4～5个环境因子共同影响,其中大气Ca、Ci、TL对其影响较大。④随着水分胁迫的加重,藤本植物类群频率出现的高低,表现为光合速率、蒸腾速率大小以次为高、中等、低,且在对照和轻度水分胁迫下,以高、中等类群的藤本植物品种居多,中度和重度水分胁迫下,以相对低等类群的藤本植物品种居多。(3)不同土壤湿度下叶片光合作用效率对CO2浓度的响应①土壤水分增高,有利于藤本植物在高CO2浓度下光合作用的进行,对其高浓度CO2的利用起到了促进作用。②随着水分胁迫的加重,藤本植物CO2饱和点逐渐降低,在高CO2浓度下,响应曲线变化比较平缓。随着水分胁迫的加重,各CO2浓度下,14种藤本植物出现低光合速率值的机率明显增加。③随着水分胁迫的加重,多数藤本植物的CE呈现下降的趋势;常春藤、三叶地锦、紫藤、大毛花、花叶等5种藤本植物的Г呈现增加趋势,其他几种藤本植物在轻度、中度水分胁迫条件下相差不是很大;多数藤本植物的RuBP最大再生速率表现出降低趋势。(4)叶绿素荧光动力学参数对水分胁迫的响应①随着水分胁迫的加重,藤本植物的FV/Fm比值随之下降,光能转化幅度降低,影响光合电子传递的正常进行,从而影响藤本植物的光合作用。②随着水分胁迫的加重,藤本植物的ΦPSⅡ值下降幅度依次增大。在对照和轻度、中度水分胁迫下,多数藤本植物的ΦPSⅡ值能够恢复到初始值大小,但严重的干旱胁迫会限制了PSⅡ反应中心的电子传递,降低了PSⅡ电子传递量子产量③随着水分胁迫的加剧,藤本植物NPQ值增大,光抑制的现象加强,以热的形式耗散的那部分光能也随着增加,热耗散能力随着干旱胁迫的加剧而增强。④随着水分胁迫的加重,藤本植物ETR日均值逐渐降低,下降幅度也依次增大。水分胁迫的加重降低光合电子传递速率,在一定程度上不能够有效耗散过剩的光能,从而导致光强过高和干旱胁迫加重对光合机构产生一定的破坏作用。(5)维持藤本植物高效用水和良好生长的适宜土壤水分阈值与有效辐射强度范围①维持美国凌霄高效生理用水和高光合生产力存在的适宜水分条件,Wm为13.5%～19.4%,Wr为49.5%～71.1%,适宜的光合有效辐射范围(PAR)为800～1600μmol·m-2·s-1。其他依次为:②紫藤Wm为13.1%～22.6%,Wr为46.5%～80.1%,PAR为600～1400μmol·m-2·s-1。③常春藤Wm为17.6%～20.5%,Wr为63.8%～74.3%,PAR为600～1400μmol·m-2·s-1。④蛇葡萄Wm为8.9%～19.8%,Wr为30.8%～68.5%,PAR为1000～1200μmol·m-2·s-1。⑤五叶地锦Wm为9.7%～14.0%,Wr为33.7%～48.7%,PAR为600～1200μmol·m-2·s-1。⑥三叶地锦Wm为8.9%～15.7%,Wr为28.6%～50.2%,PAR为400～800μmol·m-2·s-1。⑦大叶扶芳藤Wm为9.8%～15.2%,Wr为34.0%～52.7%,PAR为600～1000μmol·m-2·s-1。⑧小叶扶芳藤Wm为8.2%～18.3%,Wr为32.3%～72.2%,PAR为600～1200μmol·m-2·s-1。⑨爬藤卫矛Wm为11.2%～21.2%,Wr为41.0%～77.7%,PAR为600～1000μmol·m-2·s-1。⑩大毛花Wm为11.4%～19.8%,Wr为40.4%～70.3%,PAR为800～1400μmol·m-2·s-1。○11秧花Wm为9.0%～17.2%,Wr为31.6%～60.5%,PAR为600～1200μmol·m-2·s-1。○12花叶Wm为12.9%～17.9%,Wr为46.2%～64.2%,PAR为800～1200μmol·m-2·s-1。○13蒙花Wm为12.0%～16.4%,Wr为43.3%～59.2%,PAR为600～1400μmol·m-2·s-1。○14鸡抓花Wm为17.3%～22.3%,Wr为60.7%～78.2%,PAR为1000～1400μmol·m-2·s-1。(6)藤本植物的光适应性和水分适应性特征①鸡抓花、爬藤卫矛、大叶扶芳藤、蒙花等4种藤本植物应属于典型的阳生植物。蛇葡萄、五叶地锦、常春藤等3种藤本植物则为一般的喜光性植物。美国凌霄、大毛花、紫藤、秧花等4种藤本植物属喜光耐阴植物。小叶扶芳藤、三叶地锦、花叶等3种藤本植物应为典型的阴生植物。②在维持高光合速率的前提下,对土壤水分的耐水湿性由大到小排序依次为:小叶扶芳藤>紫藤>鸡抓花>爬藤卫矛>常春藤>三叶地锦>秧花>五叶地锦>大叶扶芳藤>美国凌霄>大毛花>蛇葡萄>花叶>蒙花。对土壤水分干旱的适应性由大到小排序依次为:三叶地锦>蛇葡萄>秧花>小叶扶芳藤>五叶地锦>大叶扶芳藤>大毛花>爬藤卫矛>蒙花>花叶>紫藤>美国凌霄>鸡抓花>常春藤。更多还原

【Abstract】 In recent years, along with exacerbation of global eco-environmental problem, ecological function of vegetation restoration and reconstruction has been one of ecological hotspots regarded by people. Moreover, light stress, drought and rise of atmosphere CO2 concentration are important ecological factors, which influence distributing and growth of vegetation. Photosynthetic gas exchange parameters has been researched on crop and economic forest centralized mostly. Research on variety rule of photosynthesis physiological index of Lianas was rather little under a series of soil moisture grads. Therefore, using , synthetically the theory of water transport of soil-plant-atmosphere continuum interface and theory of plant water use efficiency, and regarding Parthenocissus quinquefolia、Parthenocissus semicordata、Euonymus fortunei、Euonymus fortunei minimus Rhed、Campsis radicans Seen、Ampelopsis brevipedunculata、Wisteria sinensis Sweet、Lonicera japonica Thunb、Euonymus scandens Graham、Hedera neaplensis var. Sinensis et al. as experimental materials, water transport process and water physiological saving mechanism of leaf-atmosphere interface of woodiness Lianas has been studied. Thereby, quantitative relation among water transport efficiency of leaf-atmosphere interface, soil water content of root-soil interface and quantum flux of leaf-atmosphere interface are established, and stomata limit mechanism of soil moisture in root-soil interface driving WUE of leaf-atmosphere interface and chlorophyll fluorescence kinetic mechanism are explored. These theoretical and technical gists are very useful at selecting and deploying reasonable sites for eximious Lianas, in the process of vegetation restoration and reconstruction of droughty and barren hills. The results as follow:(1) The response of leaves photosynthetic efficiency to the dynamic effecters of soil moistureThe net photosynthetic rate (Pn)、transpiration rate (Tr) and water use efficiency (WUE) of Lianas leaves have notable threshold response value to the level of soil moisture and the variation of photosynthetic active radiation (PAR). We can ascertain some parameters for maintaining the natural growth and water efficient use of Lianas, such as : the maximal soil moisture deficit, the upper limit and fitting soil water content, the upper、lower limit and fitting value of PAR. For example, W. sinensis:①In order to maintain the high-level Pn and WUE of W. sinensis ,synchronously, the fitting mass water content (Wm) is about 13.1%~22.6%, relative water content (Wr) is about 46.5%～80.6%, and the optimum Wm is about19.9% (Wr is 70.9%).②The adaptability of W. sinensis to light conditions is very fargoing, and the high-level Pn and WUE is appeared in the PAR of 600～1600μmol·m-2·s-1, and the light saturation points of Pn and WUE are all about 800～1000μmol·m-2·s-1.③The most deficient degree to Wm is 10.2% (Wr is 36.2%) for the normal growth of W. sinensis, in this situation, the leaf photosynthesis organ will be badly destroyed if the number of PAR exceeds 1000μmol·m-2·s-1, and it is the critical point of destructivity in leaf photosynthesis organ.④Establishing the response model of water transport efficiency of the interface between leaf-atmosphere to PAR, we find that the non-rectangular hyperbola model is very good to simulate light-response curve, and the convexity is about 1.With the increase of soil mass water content (Wm is about 5.5%~19.4%)、relative water content(Wr) is about20.1%~71.1%, the number of light compensation point is decline while light saturation point、the maximum Pn、apparent quantity yield are all increase. When Wm is about 19.4%, the light compensation point is at the minimum of 21.61μmol·m-2·s-1, and light saturation point is at the maximum of 1400μmol·m-2·s-1.⑤With the aggravating of soil moisture stress, the reason of Pn’decline is changed from stomatal limit to No-stomatal limit. For example, the Lianas of W. sinensis, the appearance of No-stomatal limit is nearly correlative with soil moisture and light intensity. The decline of Pn is caused mainly by stomatal limit in the range of Wm between 15.7% and 22.6%, in this situation; the Pn is not affected obviously by PAR. Out of this soil moisture situation, the Pn is affected obviously by PAR, and the critical turning point of PAR is appeared with the change from stomatal limit to No- stomatal limit.(2) The response of daily trends of leaves photosynthetic efficiency under soil moisture stress ①The primary factors influencing Pn of H. neaplensis var. can be sum up two species, one is air temperature and relative humidity, the other is light intensity under abundant soil moisture. One is light intensity and atmosphere CO2 concentration, the other is air relative humidity under severe soil moisture stress.②On condition of all kinds of soil moisture, Pn of Lonicera japonica Thunb., especially the kind of L. j. cv.ungulata and L.j.cv. Variegatum,are correspondingly higher. On condition of moderate soil moisture stress, Pn of E. scandens、A. brevipedunculata、E. fortunei are correspondingly higher. Pn of Campsis radicans、E.f.var.minimus Rhed、P. quinquefolia、P. semicordata、Wisteria sinensis et al. are secondly higher. Compared with else Lianas, Pn of W. sinensis、P. quinquefolia、H. neaplensis var are lower although soil moisture condition is good.③With aggravation of soil moisture stress, transpiration rate and water use efficiency of most Lianas represents descendant trend and the variety of factors influencing transpiration rate is rather complex. From compositive factors in single factor’s relativity analysis and stepwise regression equation, the influence of environmental factors on water use efficiency of C. radicans is rather complex under soil moisture stresss. Commonly, 4~5 environmental factors influence together water use efficiency of C. radicans, especially atmosphere CO2 concentration、intercellular CO2 concentration、leaf temperature.④With aggravation of soil moisture stress, the order of Lianas’cluster frequency of Pn and Tr is high mean>middling mean>low mean. The high、middling mean amount of breed is larger under check and mild soil moisture stress, and the low mean amount of breed is larger under moderate and severe soil moisture stress.(3) The response of leaves photosynthetic efficiency on CO2 concentration under different soil moisture①The increase of soil moisture is favorable for Lianas’photosynthesis under high CO2 concentration, and accelerates the use of high CO2 concentration.②With the aggravation of soil moisture stress,the CO2 saturation point of Lianas is reduced, and the change of the response curve is very mild under high CO2 concentration.With the aggravation of soil moisture stress,the frequency of low Pn value is increase for all Lianas under every CO2 concentration. ③With the aggravation of soil moisture stress, some Lianas’carboxylation efficiency is reduced, and the CO2 compensation points of H. neaplensis var、P. semicordata、W. sinensis、L. j. cv.tomentosa、L. j.cv. Variegatum et al, Lianas is increased, and theГmean of other Lianas is almost equal under mild and moderate soil moisture stress. The maximal regeneration rate of RuBP is reduced for large quantities of Lianas.(4) The response of chlorophyll fluorescence kinetic parameters to soil moisture stress①with the aggravation of soil moisture stress, the ration of Lianas’FV/Fm is declining, and the light translation extent is low. The decline of FV/Fm affects Photosynthetic electron transport natural progress and plant photosynthesis.②with the aggravation of soil moisture stress, the decline extent of Lianas’ΦPSⅡis increased, in turn. In the soil moisture stress of check、mild、moderate, theΦPSⅡof some Lianas could renew the primary value, but the severe water stress could limit the electron transport of reaction center in the PSⅡ,reducing the quantum yield of electron transport in the PSⅡ.③with the aggravation of soil moisture stress, the photoinhibition phenomenon is strengthen, accompanying the increscent of Lianas’NPQ, and heat dissipateion ability is also strength.④with the aggravation of soil moisture stress, the daily mean of ETR is reduced , and the descending extent is increscent, in turn. The aggravation of soil moisture stress could reduce the Photosynthetic electron transport rate. In a certain, it could not consume superfluous light energy, and induce the breach of photosynthetic organ accompanying with the aggravation of soil moisture stress and intense light.(5) The fitting soil moisture threshold value and the effective range of photosynthetic active rate for maintaining different Lianas’high-efficiency water use efficiency and natural growth①In order to maintain high-efficiency physiological using water and high-level photosynthetic productivity of Campsis radicans Seen, the fitting mass water content (Wm)is about 13.5%~19.4%, relative water content (Wr) is about 49.5%～71.1%, and the fitting photosynthetic active radiation (PAR) is in the range of 800~1600μmol·m-2·s-1. and the ordinal soil moisture content and PAR of other Lianas, as follows:②For Wisteria sinensis Sweet , the fitting Wm is about 13.1%~22.6%, Wr is about 46.5%～80.1%, and the fitting PAR is in the range of 800~1600μmol·m-2·s-1.③For Hedera neaplensis var. Sinensis , the fitting Wm is about 17.6%~20.5%, Wr is about 63.8%～74.3%, and the fitting PAR is in the range of 600~1400μmol·m-2·s-1.④For Ampelopsis brevipedunculata , the fitting Wm is about 8.9%~19.8%, Wr is about 30.8%～68.5%, and the fitting PAR is in the range of 1000~1200μmol·m-2·s-1.⑤For Parthenocissus quinquefolia , the fitting Wm is about 9.7%~14.0%, Wr is about 33.7%～48.7%, and the fitting PAR is in the range of 600~1200μmol·m-2·s-1.⑥For Parthenocissus semicordata , the fitting Wm is about 8.9%~15.7%, Wr is about 28.6%～50.2%, and the fitting PAR is in the range of 400~800μmol·m-2·s-1.⑦For Euonymus fortunei , the fitting Wm is about 9.8%~15.2%, Wr is about 34.0%～52.7%, and the fitting PAR is in the range of 600~1000μmol·m-2·s-1.⑧For E.f.var.minimus Rhed , the fitting Wm is about 8.2%~18.3%, Wr is about 32.3%～72.2%, and the fitting PAR is in the range of 600~1200μmol·m-2·s-1.⑨For Euonymus scandens Graham , the fitting Wm is about 11.2%~21.2%, Wr is about 41.0%～77.7%, and the fitting PAR is in the range of 600~1000μmol·m-2·s-1.⑩For Lonicera japonica Thunb.cv.tomentosa , the fitting Wm is about 11.4%~19.8%, Wr is about 40.4%～70.3%, and the fitting PAR is in the range of 800~1400μmol·m-2·s-1.○11 For Lonicera japonica Thunb.var , the fitting Wm is about 9.0%~17.2%, Wr is about 31.6%～60.5%, and the fitting PAR is in the range of 600~1200μmol·m-2·s-1.○12 For Lonicera japonica Thunb.cv. Variegatum , the fitting Wm is about 12.9%~17.9%, Wr is about 46.2%～64.2%, and the fitting PAR is in the range of 800~1200μmol·m-2·s-1.○13 For Lonicera japonica Thunb.cv.meng , the fitting Wm is about 12.0%~16.4%, Wr is about 43.3%～59.2%, and the fitting PAR is in the range of 600~1400μmol·m-2·s-1.○14 For Lonicera japonica Thunb.cv.ungulata , the fitting Wm is about 17.3%~22.3%, Wr is about 60.7%～78.2%, and the fitting PAR is in the range of 1000~1400μmol·m-2·s-1. (6) The characters of soil moisture adaptation and light adaptation for Lianas ①L. j. cv.ungulata、E. scandens、E. fortunei、L. j. cv.meng, et al Lianas belong to typical sun plants. A. brevipedunculata、P. quinquefolia、H. neaplensis var, et al Lianas belong to general photophilous plants. C. radicans、L. j. cv.tomentosa、W. sinensis、L. j. var , et al Lianas belong to helioskiophytes . E.f.var.minimus Rhed、P. semicordata、L. j.cv. Variegatum , et al Lianas belong to typical shade plants.②In the precondition of maintaining high Pn, the order of waterlogging tolerance is E.f.var.minimus Rhed> W. sinensis > L. j. cv.ungulata > E. scandens > H. neaplensis var> P. semicordata> L. j. var> P. quinquefolia > E. fortunei > C. radicans > L. j. cv.tomentosa > A. brevipedunculata > L. j.cv. Variegatum > L. j. cv.meng . the order of drought tolerance is > P. semicordata > A. brevipedunculata > L. j. var > E.f.var.minimus Rhed > P. quinquefolia > E. fortunei > L. j. cv.tomentosa > E. scandens > L. j. cv.meng > L. j.cv. Variegatum > W. sinensis > C. radicans > L. j. cv.ungulata > H. neaplensis var.更多还原