KMS XINJIANG INSTITUTE OF ECOLOGY AND GEOGRAPHY，CAS
| 木本植物胡伯尔值沿我国西北到东南之降水梯度的变化 | |
| Alternative Title | Variation of Huber value of woody plant along a precipitation gradient from north-west to south-east of China |
| 郭勇 | |
| Subtype | 硕士 |
| Thesis Advisor | 李彦 |
| 2020-06-30 | |
| Degree Grantor | 中国科学院大学 |
| Place of Conferral | 北京 |
| Degree Discipline | 理学硕士 |
| Keyword | 胡伯尔值 比叶面积 不同气候带 分布格局 气候因素 Huber value Specific leaf area Different climate zones Distribution pattern Climatic factors |
| Abstract | 胡伯尔值（Huber value， Hv）被定义为树冠上部枝条边材面积与叶面积的比值，是度量植物地上部分水力性状的一个指标，可以看作是木质部（除了髓、心材、茎皮和韧皮部）投资与叶片所获得收益的比率，是植物水分平衡和干旱响应的核心属性。揭示胡伯尔值的分布格局及其与比叶面积和气候因素的关系，可以促进陆地生物圈模型中植物水力和生物量分配的参数化，有助于理解气候变化背景下全球植物生物量分配以及植物对干旱胁迫的响应。本研究以中国西北-东南样带为研究平台，沿降水梯度从东南到西北依次在天目山、鸡公山、安塞、沙坡头、瓜州、阜康等地选择了 6 个典型生态系统，通过野外采样和室内分析相结合的方法，研究不同降水水平下胡伯尔值的分布格局以及其隐含的权衡关系，定量分析了气候因素对胡伯尔值的影响。本文的主要研究结论如下：（1） 胡伯尔值与比叶面积的分布格局。 个体水平上，胡伯尔值与比叶面积均值分别为 2.8×10-6 和 174.26cm2 g-1，变化范围分别为 0.5×10-7~0.23×10-4 和7.69~889.43cm2 g-1；在生活型水平上，灌木的胡伯尔值为 3.6×10-6，显著高于乔木的 2.5×10-6（P<0.05）， 常绿树木的胡伯尔值为 1.9×10-6，显著小于落叶树木的2.9×10-6（P<0.05）， 灌木和乔木的比叶面积之间没有显著性差异，分别为 156.121和 159.20 cm2 g-1，而常绿树的比叶面积（106.52 cm2 g-1）显著小于落叶树（167.72cm2 g-1； P<0.05）；在生态系统水平， 6 个生态系统胡伯尔值表现为瓜州>沙坡头>阜康>安塞>天目山>鸡公山，其中瓜州为最大值 0.07×10-4，天目山和鸡公山最小值 0.02×10-4 且他们之间差异不显著；比叶面积在不同生态系统间分布趋势为天目山>鸡公山>安塞>沙坡头>阜康>瓜州，在天目山为最大值 259.23 cm2 g-1，沙坡头、瓜州、阜康间没有显著性差异(P>0.05)。（2） 胡伯尔值与比叶面积的权衡关系。 比较不同生态系统和不同生活型植物边材面积与叶面积的关系发现：无论是在生态系统水平还是生活型水平，植物边材面积与叶面积均满足管道模型和最优分配理论，即叶面积始终和边材面积呈正比，会将资源优先分配给边材来保证植物的正常供水；对于叶面积和叶干重，无论在生态系统水平还是物种水平，两者的异速生长指数均小于 1，即叶面积与叶干重呈非等速关系且会优先向叶干重分配资源。（3） 胡伯尔值与比叶面积与气候因素的关系。 在物种水平上，降水、温度均与胡伯尔值呈负相关，而大气水汽压差与胡伯尔值呈正相关；对于比叶面积来说，降水、温度均与比叶面积呈正相关，而大气水汽压差与比叶面积呈负相关；并且从结果可以看出，气候指标对比叶面积的拟合程度均好于胡伯尔值。通过比较不同算法的干燥度指数与生态系统胡伯尔值和比叶面积的拟合程度发现：与植被生长期温度和降雨量相关的干燥度指数与胡伯尔值的拟合程度最好（R2=0.971）；而与年降水量和年均温相关的干燥度指数与比叶面积拟合程度最好为（R2=0.971），不同生活型植物与气候指标间的关系有所差异。 |
| Other Abstract | The Huber value (Hv) was calculated as the stem cross-sectional areas (m2) perleaf area (m2) of the branch in the upper part of the crown, which is a core attribute ofplant water balance and drought response. The full parameterization of hydraulic andbiomass scales in terrestrial biosphere models was need to reveal the distributionpattern of Huber value and its relationship with specific leaf area(SLA) and climaticfactors, and it also useful to understand the global plant biomass allocation in thecontext of climate change and plant response to drought stress. The study focuses onsix typical ecosystems (Tianmu Mountain, Jigong Mountain, Ansai, Shapotou,Guazhou, Fukang) along the northwest-southeast transect of China about 3800 km,which is a unique belt of vegetation formed by the natural aridity gradients. Throughfield sampling and laboratory analysis, the distribution pattern of Huber values atdifferent levels and its trade-off relationship were studied, and the influence of climatefactors on Huber values was quantitatively analyzed. The main research conclusionsof this article are as follows:(1) Distribution pattern of Huber value and specific leaf area. At the individuallevel, the mean values of Huber value and specific leaf area are 2.8×10-6 and174.26cm2 g-1, respectively, and the ranges of variation are 0.5×10-7~0.23 ×10-4 and7.69~889.43cm2 g-1; At the life form level, the Huber value of shrubs is 3.6 ×10-6,which is significantly higher than that of trees 2.5×10-6 (P <0.05); the Huber value ofevergreen trees is 1.9×10-6, Significantly less than 2.9×10-6 (P <0.05) of deciduoustrees; there is no significant difference between the specific leaf areas of shrubs andtrees (156.121 and 159.20 cm2 g-1, respectively), while the specific leaf area ofevergreen trees (106.52 cm2 g-1) is significantly smaller than deciduous trees (167.72cm2 g-1; P <0.05); At the ecosystem level, the Huber values of the six ecosystems aresorted as Guazhou> Shapotou> Fukang> Ansai> Tianmu Mountain> Jigong Mountain,where the maximum value of Guazhou is 0.07×10-4, The minimum value of theTianmu Mountain and Jigong Mountain is 0.02×10-4, and the difference between them is no significant; the distribution trend of specific leaf area among differentecosystems is Tianmu Mountain> Jigong Mountain> Ansai> Shapotou> Fukang>Guazhou, the largest value in Tianmu Mountain was 259.23 cm2 g-1. There was nosignificant difference between Shapotou, Guazhou and Fukang (P> 0.05).(2) Trade-off relationship between Huber value and specific leaf area.Comparing the relationship between the sapwood area and leaf area of plants indifferent ecosystems and different life forms, it is found that whether at the ecosystemlevel or the life form level, the pipe model and optimal distribution theory wasbroadly confirmed, based on the measurements of plant sapwood area and leaf area. Itis always proportional to the area of leaf and sapwood, and resources will bepreferentially allocated to sapwood when focused on water stress; for leaf area anddry leaf weight, both at the ecosystem level and species level, the allometric growthindex of both is less than 1 That is, the leaf area and the leaf dry weight have anon-constant velocity relationship, and resources are preferentially allocated to theleaf dry weight.(3) Relationship between Huber value, specific leaf area and climatic factors. Atthe species level, precipitation and temperature are negatively correlated with theHuber value, while atmospheric water vapor pressure differential is positivelycorrelated with the Huber value; for specific leaf area, precipitation and temperatureare positively correlated with specific leaf area, and the atmospheric water vaporpressure difference is negatively related to the specific leaf area. By comparing thefitting degree of the aridity index of different algorithms with the Huber value andspecific leaf area of the ecosystem, it is found that the aridity index related to thetemperature of the vegetation growth period and the Huber value fit best (R2=0.971);And the aridity and the specific leaf area related to the annual precipitation and theannual average temperature are best fitted (R2=0.971), and the relationship betweendifferent life forms of plants and climate indicators is different. |
| Subject Area | 生态学 |
| Language | 中文 |
| Document Type | 学位论文 |
| Identifier | http://ir.xjlas.org/handle/365004/15420 |
| Collection | 中国科学院新疆生态与地理研究所 研究系统 |
| Affiliation | 中国科学院新疆生态与地理研究所 |
| First Author Affilication | 中国科学院新疆生态与地理研究所 |
| Recommended Citation GB/T 7714 | 郭勇. 木本植物胡伯尔值沿我国西北到东南之降水梯度的变化[D]. 北京. 中国科学院大学,2020. |
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