KMS XINJIANG INSTITUTE OF ECOLOGY AND GEOGRAPHY，CAS
| 基于生态化学计量学分析的荒漠藓类结皮斑块环境适应性研究 | |
| Alternative Title | Study of environmental adaptability of desert moss crusts based on ecological stoichiometry |
| 李永刚 | |
| Subtype | 博士 |
| Thesis Advisor | 张元明 |
| 2020-06-30 | |
| Degree Grantor | 中国科学院大学 |
| Place of Conferral | 北京 |
| Degree Discipline | 理学博士 |
| Keyword | 齿肋赤藓斑块 边缘效应 面积效应 生态化学计量学 土壤养分 Patch of S. caninervis edge effect area effect stoichiometry soil nutrient |
| Abstract | 生物土壤结皮广泛分布于干旱荒漠区地表，在维持荒漠生态系统结构与功能方面具有重要的生态功能。 藓类结皮是生物土壤结皮中重要的组分之一， 自然状态下通常呈现出典型的斑块状分布特征。 目前对荒漠藓类结皮植物环境适应性的研究多集中于藓类植物个体对环境的适应性， 分别从基因调控、细胞结构、 形态特征、生理生化等方面揭示藓类植物对干旱、高温等不利环境的适应性。 自然环境下， 藓类结皮主要以斑块的形式存在，但对于这种斑块式聚集分布是否有利于藓类植物适应不利环境条件的研究鲜有报道。 阐明荒漠藓类结皮斑块的生态效应，有助于加深对荒漠藓类植物环境适应性和生态功能的理解，为荒漠生态系统结构与功能研究提供参考依据。本研究以古尔班通古特沙漠为研究区，选择该沙漠生物土壤结皮中优势藓类植物齿肋赤藓 (Syntrichia caninervis Mitt.)斑块为研究对象， 通过测定碳、氮磷等不同元素含量， 分析齿肋赤藓斑块中心区域和边缘区以及不同面积斑块中齿肋赤藓植物体和斑块下层土壤的生态化学计量特征，以及不同微生境下和不同空间采样距离的齿肋赤藓斑块生态化学计量特征，阐明藓类结皮斑块对不利环境的适应机理。 本研究主要结果如下：1. 齿肋赤藓斑块在古尔班通古特沙漠中主要以面积小于 100 cm2 的斑块分布为主， 在沙丘底部主要呈聚集分布。 齿肋赤藓斑块面积小于 100 cm2 的斑块占调查斑块总数 87%以上，小于 10 cm2 的斑块数占调查总数的 50%以上。样方内利用空间点格局分析，发现 K(r) 值显著高于 K(r)the 上限值， 认为齿肋赤藓斑块呈聚集分布。 沙漠不同区域齿肋赤藓斑块面积组成比例显著不同， 沙漠边缘小型斑块占该调查点斑块数的比例较沙漠腹地高， 边缘较腹地斑块破碎化程度高。2. 齿肋赤藓斑块中心区域生态化学计量特征较边缘区高， 形成微尺度上“肥岛”， 从而影响荒漠土壤系统土壤养分循环。 斑块中心区域齿肋赤藓植物体氮、磷含量（ N: 15.151 mg/g， P: 1.830 mg/g） 显著高于边缘区齿肋赤藓植物体氮、磷含量（ N: 13.431 mg/g， P: 1.507 mg/g）。结皮层斑块和结皮斑块下层土壤速效氮与速效磷在斑块中心区域和边缘区无显著（ P>0.05） 差异。结皮层斑块土壤全磷在中心区域和边缘区无显著（ P>0.05） 差异， 结皮斑块下层中心区域土壤全磷含量显著（ P<0.05） 高于结皮斑块边缘区下层土壤。 齿肋赤藓斑块中心区域和边缘区结皮层斑块土壤有机碳、全氮、速效氮、速效磷含量显著（ P<0.05） 高于结皮斑块下层土壤有机碳、全氮、速效氮、速效磷含量。斑块中心区域结皮层斑块土壤与结皮下层土壤全磷含量无显著（ P>0.05） 差异， 齿肋赤藓斑块边缘区结皮层斑块土壤全磷含量显著（ P<0.05） 高于结皮斑块下层土壤。3. 齿肋赤藓斑块生态化学计量特征具有明显的面积效应，随斑块面积的增加有利于齿肋赤藓斑块在荒漠生态系统中的生长。 齿肋赤藓斑块面积增加有利于齿肋赤藓斑块生态化学计量特征的积累。 随斑块面积的增加齿肋赤藓植物体地上部分的氮含量和地下部分的碳、氮、磷含量均呈上升趋势。 斑块面积对齿肋赤藓植物体地上部分和地下部分碳含量无显著（ P>0.05） 的影响。 齿肋赤藓植物体地上部分（茎叶）的氮、磷含量显著（ P<0.05） 高于地下部分（假根） 氮、磷含量，而碳氮比和碳磷比显著（ P<0.05） 低于地下部分。斑块面积的增加能够显著的增加土壤蔗糖酶活性，对土壤脲酶、碱性磷酸酶无显著（ P>0.05） 影响。4. 微生境（裸露地、活灌丛、死灌丛） 显著影响齿肋赤藓斑块生态化学计量特征，且活灌丛下斑块面积大小对齿肋赤藓斑块生态化学计量特征无显著（ P>0.05） 影响。活灌丛下齿肋赤藓植物体氮、磷含量高于裸露地和死灌丛下。不同微生境对齿肋赤藓植物体碳含量无显著（ P>0.05） 影响。 齿肋赤藓植物体地上部分氮、 磷含量显著（ P<0.05） 高于地下部分，地下部分碳氮比和碳磷比高于地上部分。 土壤有机碳 (SOC)、土壤全氮 (STN)、土壤有效磷 (SAP)、碳磷比和氮磷比在死灌丛下最高，而裸露地最低。土壤总磷 (STP)和土壤有效氮 (SAN)、碳氮比和土壤有效氮均无显著（ P>0.05） 差异。土壤脲酶和硝酸还原酶活性在死灌丛下最高， 裸露地下斑块下层土壤蔗糖酶和土壤 β-葡萄糖苷酶活性最高。死灌丛下斑块下层土壤碱性磷酸酶活性最低，裸露地与活灌丛下无显著差异。5. 不同空间尺度下，齿肋赤藓斑块生态化学计量特征间差异不同， 齿肋赤藓斑块生态化学计量特征具有空间异质性。 在相邻沙丘间齿肋赤藓植物体和结皮斑块下土壤的生态化学计量特征无显著（ P>0.05） 差异。随沙丘间距离的增加，沙丘间齿肋赤藓斑块生态化学计量特征呈显著（ P<0.05） 不同。 在古尔班通古特沙漠腹地相距 5 km 沙丘间齿肋赤藓植物体地下部分的碳、氮、磷、钾含量具有显著（ P<0.05） 差异， 地上部分氮、磷含量呈显著不同。 该沙漠腹地沙丘间结皮斑块下层土壤生态化学计量特征无显著（ P>0.05） 差异，而土壤 pH 和电导率均具有显著不同。通过相关性分析和 Mantel 分析发现土壤的氮、磷是影响齿肋赤藓生态化学计量特征的主要因素。6. 古尔班通古特沙漠中相距 10 km 的沙丘间齿肋赤藓斑块生态化学计量特征显著不同。 该沙漠中齿肋赤藓植物体地上部分的碳、磷、钾含量显著（ P<0.05）高于地下部分。无齿肋赤藓斑块覆盖的土壤有机质、总氮和总磷含量在相距 10km 的沙丘间具有显著（ P<0.05） 的差异， 但斑块下表层土壤中有机质、总氮和总磷含量无显著（ P>0.05） 差异。 斑块下层土壤硝态氮与齿肋赤藓植物体磷含量间呈显著（ P<0.05） 的正相关关系。齿肋赤藓植物体碳与氮， 碳与磷， 氮与磷元素间呈显著（ P<0.05） 的正效应， 而碳与钾元素间呈显著（ P<0.05） 的负效应。齿肋赤藓植物体氮、磷、钾元素与结皮斑块下层土壤养分间的结构方程分析发现，齿肋赤藓植物体氮、磷、钾元素主要养分来源于土壤中的土壤铵态氮、 速效磷和钾， 由地下部分吸收、转化、运输至地上部分。研究结果表明， 荒漠藓类结皮斑块主要以小型斑块分布，且在沙丘底部呈聚集分布。荒漠藓类植物斑块具有与景观生态学中维管束植物相似的斑块效应，齿肋赤藓斑块生态化学计量特征具有明显的边缘效应和面积效应。齿肋赤藓斑块生态化学计量特征易受微环境的影响，不同空间尺度下齿肋赤藓斑块生态化学计量特征空间异质性不同。斑块内齿肋赤藓植物体生态化学计量特征易受土壤生态化学计量特征的影响。 齿肋赤藓植物体的养分含量在古尔班通古特沙漠中具有较强的可塑性， 齿肋赤藓植物体可以通过改变其元素含量以平衡物质与能量循环、 维持其在恶劣环境下生长， 从而适应荒漠严酷的自然环境和气候条件。 |
| Other Abstract | Biological soil crusts are widely distributed on the surface of arid desert areas, andhave important ecological functions in maintaining the structure and function of desertecosystems. Moss crusts are one of the most important components in biological soilcrusts, and usually show a typical patchy distribution. The environmental adaptabilityof S. caninervis crust has been determined in several ways, including by molecular,cytobiological, morphological and physiological methods. Their studies have focusedon the environmental adaptability of individual S. caninervis plants, and revealed theresponse of moss plant on the harsh environment, such as drought and high temperatureenvironment. In the natural environment, mosses are patchily distributed in desertecosystems, but there are few reports on whether this patch aggregation distribution isconducive to adapting moss plants in harsh environmental. Clarifying the ecologicaleffects of desert moss patch will help deepen the understanding of the environmentaladaptability and ecological functions of desert moss plants, and provide a reference forthe study of the structure and function of desert ecosystems.In this study, the Gurbantunggut Desert was selected as the research field. Thedominant moss Syntrichia caninervis Mitt was selected as the research object. The C,N, and P stoichiometry of moss and soil under moss patches were measured. And themoss and soil stoichiometry were analysised in patch central region and edge areas, andin different patch size, different microhabitats and different spatital distances. Clarif theadaptation mechanism of moss patches by analyzing stoichiometric characteristics ofmoss and soil. The main results of this study are as follows:1. The distribution of moss patch was mainly distributed with an area of less than100 cm2, and they showed aggregate distribution at the bottom of the dunes. The patcheswith area of less than 100 cm2 accounted for more than 87% of total number of patches.And the patches with area of less than 10 cm2 accounted for more than 50% of the totalpatches. The ratios of moss patch area composition in different areas of the desert aresignificantly different, and the degree of fragmentation at the edge of the desert is higher (P<0.05) than that of the centre.2. The moss and soil stoichiometry in the central region of moss patch is higherthan that in the edge region, forming a "fertility island" on the microscale, which affectsthe soil nutrient cycle. The nitrogen and phosphorus contents in the central region ofmoss patch (N: 15.151 mg / g, P: 1.830 mg / g) are higher (P<0.05)than those in theedge area (N: 13.431 mg / g, P: 1.507 mg / g). There was no significant (P>0.05)difference between soil available nitrogen, available phosphorus in the central regionand edge region of the moss patch. There was no significant (P>0.05)differencebetween soil under moss patch available nitrogen, available phosphorus in the centralregion and edge region of the moss patch. There was no significant difference betweensoil total phosphorus content in the central region and edge region of the moss patch.The contents of organic carbon, total nitrogen, available nitrogen and availablephosphorus of the moss crust soil in the central and edge region were significantlyhigher than that in the soil under moss crust.3. The moss stoichiometry has obvious area effects. Increasing area of moss patchis conducive to the growth of moss in desert ecosystems. Increasing the area of mosspatch is conducive to the accumulation of stoichiometric characteristics of moss patch.With the increase of moss patch area, the nitrogen content in above-ground part of mossand the carbon, nitrogen and phosphorus content in below-ground part of mosssignificantly (P<0.05) increased. Patch size had no significant (P>0.05) influence onmoss C contents in above-ground and below-ground. The nitrogen and phosphoruscontent in the above-ground part (stems and leaves) of moss was significantly (P<0.05)higher than the nitrogen and phosphorus content in the belowground part (rhizoid),while the ratios of C:N and C:P in the above-ground parts of moss were significantly(P<0.05) lower than those in the below-ground part of moss. The increase of moss patcharea can significantly (P<0.05) increase soil sucrase activity, but has no significant(P>0.05) effect on soil urease and alkaline phosphatase.4. Microhabitat (expose area, under living shrub, under dead shrub) significantlyaffected the stoichiometry characteristics of moss patch, and under the live shrub, thesize of moss patch area had no significant (P>0.05) effect on the stoichiometry of mosspatch. Nitrogen and phosphorus contents of moss under living shrubs were higher(P<0.05) than those in expose area and dead shrubs. The different microhabitats had nosignificant (P>0.05) effect on the carbon content of moss. The nitrogen and phosphoruscontent in the above-ground part of moss was significantly higher (P<0.05) than that inthe below-ground part of moss. Soil organic carbon (SOC), soil total nitrogen (STN),soil available phosphorus (SAP), ratios of C:N and N:P were the highest under deadshrubs and the lowest in expose area. No significant (P>0.05) differences were foundin soil total phosphorous (STP) and soil available nitrogen (SAN), or in ratios of C:Nand SAN:SAP. Higher soil urease (SUE) and soil nitrate reductase (SNR) activitieswere found in soil under dead shrubs, while higher (P<0.05) soil sucrase (STC) and soilβ-glucosidase (SBG) activities were respectively found in exposed ground and underliving shrubs. Soil alkaline phosphatase (AKP) activity reached it’s the lowest (P<0.05)value under dead shrubs, and there was no significant (P>0.05) difference between themicrohabitats of in exposed ground and under living shrubs.5. At different spatial scales, the stoichiometry characteristics of moss aresignificantly different, and the stoichiometric characteristics of the moss patch havespatial heterogeneity. There were no significant (P<0.05) differences in thestoichiometry characteristics of moss and soil under moss patch between adjacent dunes.With the increase of the distance between the dunes, stoichiometry characteristics ofmoss patch are significantly (P<0.05) different between the dunes. The carbon (C),nitrogen (N), phosphorus (P), and potassium (K) contents in the below-ground parts ofmoss have significant (P<0.05) differences in different dunes of 5 km distance. Thenitrogen and phosphorus contents in the above-ground parts of moss are significantly(P<0.05) different. The stoichiometric of the soil under moss patches were notsignificantly (P>0.05) different, while the soil pH and electrical conductivity weresignificantly different. Through correlation analysis and Mantel analysis, it was found that moss stoichimetry was mainly influenced by soil nitrogen and phosphorus.6. In 10 km spatital scale, the stoichiometry characteristics of moss patches weresignificant difference. The carbon, phosphorus, and potassium contents in the aboveground part of moss were significantly higher (P<0.05) than those in the below-groundpart of moss. The contents of soil without moss crust organic matter, total nitrogen andtotal phosphorus had significant (P<0.05) differences among sand dunes 10 km apart,but there was no significant (P>0.05) difference in contents of soil under moss crustorganic matter, total nitrogen and total phosphorus. There was a significant (P<0.05)positive correlation between nitrate nitrogen in the soil under moss patch andphosphorus content of S. caninervis plant. There were significantly (P<0.05) positiveeffects between carbon and nitrogen of moss, between carbon and phosphorus of moss,between nitrogen and phosphorus elements of moss, while the carbon and potassiumelements showed significant negative effects. The analysis of the structural equationmodel between the nitrogen, phosphorus, and potassium elements in moss and the soilnutrients under moss patch revealed that the main nutrients of the nitrogen, phosphorus,and potassium elements in moss were derived from soil ammonium nitrogen andavailable phosphorus and potassium, which absorbed and transported to the aboveground part by the below-ground part of moss.The results showed that the patchy patches of desert mosses were mainlydistributed as small patches and clustered at the bottom of dunes. Patch effect of desertmoss patches is similar to that of vascular plants in landscape ecology. Thestoichiometric characteristics of moss patches are easily influenced by themicroenvironment. The spatial heterogeneity of the stoichiometric characteristics ofmoss patch is different among different spatial scales. The stoichiometric characteristicsof moss are easily affected by soil stoichiometric. The nutrients content of moss hasstrong plasticity. Moreover moss patch can balance the circulation of material andenergy, and maintain its growth in harsh environment by changing its element content. |
| Subject Area | 植物学 |
| Language | 中文 |
| Document Type | 学位论文 |
| Identifier | http://ir.xjlas.org/handle/365004/15433 |
| 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 | 李永刚. 基于生态化学计量学分析的荒漠藓类结皮斑块环境适应性研究[D]. 北京. 中国科学院大学,2020. |
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