KMS XINJIANG INSTITUTE OF ECOLOGY AND GEOGRAPHY，CAS
| 天山西部新疆野苹果叶片和土壤养分化学计量特征 | |
| Alternative Title | Stoichiometry of leaf and topsoil in Malus sieversii communities in western Tianshan Mountains in Xinjiang, China |
| 玛孜依热阿·努尔海拉提 | |
| Subtype | 硕士 |
| Thesis Advisor | 张元明 |
| 2019-06-30 | |
| Degree Grantor | 中国科学院大学 |
| Place of Conferral | 北京 |
| Degree Discipline | 理学硕士 |
| Keyword | 生态化学计量学 新疆野苹果 土壤养分 叶片养分 空间异质性 季节动态 养分回收率 Eco-stoichiometric Malus sieversii Soil nutrient Leaf nutrient Environmental factor Spatial heterogeneity |
| Abstract | 新疆野苹果是第三纪孑遗物种，是宝贵的野生果树资源。近年来，新疆野苹果群落出现了严重的生态退化现象，但这是否会导致新疆野苹果群落土壤和叶片养分化学计量特征的改变尚不得而知。本研究以天山西部新疆野苹果优势分布区为例，开展了不同空间和时间尺度下新疆野苹果群落表层土壤和叶片样品的生态化学计量变异特征的系统性研究，主要获得以下研究结果：新疆野苹果群落表层土壤生态化学计量特征及其影响因素。对伊犁河谷及塔城地区 6 县新疆野苹果群落表层土壤（0‒10 cm）有机碳（C）、全氮（N）、全磷（P）、全钾（K）、速效氮（AN）、速效磷（AP）和速效钾（AK）的化学计量特征研究表明，除 K、 AP、 AK 含量和 N:P 外，伊犁地区土壤养分化学计量值均高于塔城地区，但后者具有较低的变异系数。新疆野苹果群落土壤养分含量及化学计量比在县级尺度上均有显著差异。土壤 C‒N、 C‒P、 N‒P、 AP‒AK 之间具有显著的线性和非线性相关关系，且多数土壤养分含量与其化学计量比之间具有显著的线性相关关系。 CCA 分析表明，纬度、坡向、海拔及年降水量是新疆野苹果群落土壤化学计量特征的主要影响因子。新疆野苹果叶片养分化学计量特征在不同海拔和地区间的空间变异格局。结果表明，不同海拔梯度上新疆野苹果叶片多数化学计量指标均有显著变化趋势，具体而言， 2016 年野苹果叶片的 C、 N、 P 含量和 N:P 与海拔呈显著正相关关系（p < 0.01），而 2017 年野苹果叶片养分化学计量特征随海拔梯度的变化趋势与2016 年的变化趋势相反，多数养分指标与海拔呈显著负相关关系， 不同分布区间叶片养分的化学计量特征大多具有显著差异，且多具有年际差异。植株长势显著影响叶片化学计量特征，其中相对健康株叶片 C、 N 及 C:P 和 N:P 较高，而中等退化株叶片 P 含量最高而 N:P 最低，即中等退化株更易受到 N 限制。另外，根据养分限制类型判断标准得出新疆野苹果叶片养分属于 N 限制，但从不同年份的角度来看， 2017 年叶片 N 限制程度较 2016 年有所缓和。不同健康程度新疆野苹果叶片养分化学计量特征的季节动态和养分回收效率。研究表明，健康株、中等退化株和严重退化株 3 种退化程度的新疆野苹果叶片中养分元素的季节动态基本一致，即 N、 P、 K 含量在整个生长季内逐渐降低N:K 和 P:K 随时间表表现出先减少后增加的趋势， N:P 则表现出显著的波动趋势。叶片 N、 P、 K 都有一定程度的回收，但严重退化株的叶片养分回收率最低，反映了濒死野苹果树的养分保存和再利用能力衰退。 3 种退化程度植物叶片中养分含量与土壤养分并不存在显著的相关性。综上，新疆野苹果生长主要受 N 限制，且其化学计量特征及养分限制类型在不同生长季和不同年份间有所差异。种群退化影响了野苹果叶片化学计量特征并降低了养分回收率，进一步加重了植株的养分限制状况。 |
| Other Abstract | Malus sieversii is the Tertiary relict tree species and valuable resource of wild fruittree. In recent years, a serious ecological degradation in M. sieversii communityoccurred. Whether the degradation of the plant community would lead to the change inleaf and soil nutrient stoichiometric characteristics is still unclear. In this study, thedominant distribution area of M. sieversii in the western Tianshan Mountains wasselected as the study area, the eco-stoichiometric characteristics of leaf and soil samplesof M. sieversii communities at different spatial and temporal scales were systematicallystudied, and the following main research results were obtained:Ecological stoichiometric characteristics of soils in M. sieversii communities andthe influencing factors. Studies on the soil organic carbon (C), total nitrogen (N), totalphosphorus (P), total potassium (K), available nitrogen (AN), available phosphorus (AP)and available potassium (AN) in topsoils from six counties in Yili Valley and Tachengregion showed that, except for stoichiometric values of K, AP, AK and N:P,stoichiometric values in Yili region were significantly higher than those in Tachengregion, while Tacheng region has a lower Variation Coefficient. Soil nutrient contentand their stoichiometric ratios differed significantly in the 6 counties. Most of the soilnutrient content and its stoichiometric ratio exhibited significant linear correlation.Significant linear correlations were found between C and N content, and between C andP content. Canonical Correlation Analysis (CCA) results showed that the slope, latitude,altitude and the amount of precipitation were the main factors which influence thestoichiometric characteristics of soil nutrients in M. sieversii communities in our studyregion.Spatial distribution patterns of leaf nutrition stoichiometric characteristics in M.sieversii at different altitudes and regions.The results indicate that: Most of thestoichiometric indices of leaves in M. sieversii showed a significant change trend atdifferent elevation gradients, specifically, the leaf C, N, P concentration and N:Pcontents of M. sieversii in 2016 were positively correlated with elevation (P < 0.01).However, the variation tendency of leaf nutrition stoichiometric in 2017 was contraryto that in 2016, most of the nutrient indices were negatively correlated with elevation(P < 0.01). There were also significant differences in most of the stoichiometriccharacteristics of leaf nutrients in different distribution areas, and most of them have inter-annual differences. Plant growth state significantly affected the stoichiometriccharacteristics of leaves. In which the healthy trees leaf C, N content C:P, N:P werehigher, while P content in leaves of medium degradation trees was the highest and N: Pwas the lowest, and the nutrient limitation type of medium degradation trees belongs toN limitation.Seasonal variation and resorption of leaves nutrient in M. sieversii with differenthealth conditions. The results showed that, in each degradation gradient, observing adecrease in foliar N, P, and K, during the growing season. There are relatively high N,P and K resorption in M. sieversii, disease trees has the lowest nutrient resorption, itreflects the decline characteristics of nutrient preservation ability of severely degradedM. sieversii. We determined no significant correlations between soil nutrient contentsand foliar nutrient concentrations in any of the three degradation gradient.In summary, the leaf nutrient of M. sieversii was mainly limited by N, and the leafnutrient stoichiometric characteristics and limitation types were varied with growingseasons and years. Population degradation affected the leaf nutrient stoichiometriccharacteristics and nutrient resorption, which further aggravated the nutrient limitationof M. sieversii. |
| Subject Area | 植物学 |
| Language | 中文 |
| Document Type | 学位论文 |
| Identifier | http://ir.xjlas.org/handle/365004/15349 |
| 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 | 玛孜依热阿·努尔海拉提. 天山西部新疆野苹果叶片和土壤养分化学计量特征[D]. 北京. 中国科学院大学,2019. |
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