KMS XINJIANG INSTITUTE OF ECOLOGY AND GEOGRAPHY,CAS
古尔班通古特沙漠南缘梭梭群落水分来源 | |
傅思华 | |
Subtype | 硕士 |
Thesis Advisor | 杨涛 ; 胡顺军 |
2017-05-01 | |
Degree Grantor | 中国科学院大学 |
Place of Conferral | 新疆乌鲁木齐 |
Degree Discipline | 理学硕士 |
Keyword | 古尔班通古特沙漠 梭梭 水分来源 同位素技术 Gurbantunggut Desert H.ammodendron water sources stable isotope |
Abstract | Haloxylon ammodendron is a dominant plant species in the Gurbantünggüt Desert. The study of the water source of H. ammodendron community under natural conditions is helpful to understand the water consumption mechanism more deeply. And it’s also in favor of exploring the change of the water use pattern of H. ammodendron dynamic and adaptation strategies under the condition of the change of hydrological characteristics on the ecological process. Then, providing scientific basis for the study of the protection and restoration of plant diversity in arid area under the condition of climate change. To investigate the dynamics of water usage of these plants, we used the direct comparison method, Iso-Source model and the mean depth of water uptake model. The main results were as follows: (1)The water source characteristics of H. ammodendron H. ammodendron as one of the main species of the Gurbantunggut desert, the root system has the characteristics of "two states", and there are obvious seasonal differences in water use. During April to May, the main water source of Haloxylon ammodendron were shallow soil water, deep soil water and groundwater. As the temperature increased, because of the strong evaporation and plant water effect, shallow soil water moisture content decreased obviously, H. ammodendron mostly use of soil water soil depth gradually move down. During April to September, the average depth of H. ammodendron using soil water also moved along with the changing seasons.The growth and development of root system resulted in the difference of water use among H. ammodendron. The root system of young H. ammodendron was immature, so its root system was more active than middle-aged H. ammodendron and mature H.ammodendron, and the utilization of surface soil water was significantly lower than the later two. In June, the main water source of moddle-aged H. ammodendron was 250-350 cm layer soil water, the main water source of mature H. ammodendron was 180-250 cm layer soil water. From July to September, mature H. ammodendron was the most concentrated soil layer of soil water, followed by middle-aged, the most extensive range was young H. ammodendron. Deep soil water and groundwater have been the main source of water for mature H. ammodendron, and deep soil water is the main source of water for middle-aged and young H. ammodendron.(2)The water source characteristics of H. ammodendron community The main soil water of Erodium oxyrrhynchum, Sisymbrium polymorphum, Seriphidium santolinum and Suaeda glauca was 8-65 cm layer soil water, there were still some differences in soil water use, and the seasonal variation of soil water use of Seriphidium santolinum and Suaeda glauca was significant. In May, The main water source of Suaeda glauca grown in the space was concentrated in 0-10 cm soil layer, the average depth of soil water use was 8.43 cm. In August, the depth of soil water that used moved down, and the average depth of soil water utilization was 41.2 cm. On the ground, Seriphidium santolinum and Suaeda glauca mainly use the 20-40 cm soil layer, and the depth of soil respectively were 22.3 cm and 57.6 cm in May. In August, which make use of soil water depth increased, focused on 0-20 cm soil layer soil water, the average depth was 12.2 cm.H.ammodendron did not affect the water use characteristics of Sisymbrium polymorphum. The results showed that the soil moisture utilization of Erodium oxyrrhynchum and Seriphidium santolinum in May and Suaeda glauca in August were less affected by H. ammodendron. The soil water use of Suaeda glauca in May and Seriphidium santolinum in August greatly affected by H.ammodendron. Sisymbrium polymorphum, Seriphidium santolinum and Suaeda glauca under the canopy had a competition about soil moisture, while the plants in the space area had no competition. |
Other Abstract | 梭梭(Haloxylon ammodendron)作为古尔班通古特沙漠的主要建群种,研究天然条件下梭梭群落水分来源有利于更深入地认识其耗水机制,更好地探讨在气候变化下水文特征的变化对梭梭生态过程的影响,进而预测梭梭对气候变化的水分利用动态变化及适应策略,为研究气候变化条件下干旱区植物多样性的保护与恢复提供科学依据。本文利用稳定同位素技术结合直接相关法、Iso-source 模型以及平均深度模型,定量研究了古尔班通古特沙漠南缘梭梭群落水分来源。主要结果如下:(1)梭梭水分来源特征梭梭根系具有“二态性”特征,水分利用存在明显的季节性差异。梭梭在 4-5 月主要利用的潜在水源为含水量较高浅层土壤水、相对稳定的深层土壤水以及地下水。随着温度的增高,强烈的蒸发作用以及植物的耗水作用,浅层土壤水含水量明显降低,此时梭梭主要利用土壤水的土层深度逐渐向下移动。幼龄梭梭根系发育不成熟,对表层土壤水的利用明显低于中龄梭梭以及成熟梭梭。6 月中龄梭梭与幼龄梭梭主要利用 250-350 cm 土层土壤水,成熟梭梭主要利用土壤水的土层范围更大,主要集中于 180-350 cm 土层,且对地下水的利用比例约是中龄梭梭及幼龄梭梭的 2 倍。7 月至 9 月,成熟梭梭主要利用土壤水的土层范围最集中,中龄梭梭次之,幼龄梭梭范围最广。4-5 月,土壤含水量较高的浅层土壤水是梭梭重要水分来源之一;深层土壤水及地下水一直是成熟梭梭的主要水分来源,深层土壤水是中龄梭梭及幼龄梭梭主要水分来源。(2)梭梭群落植物水分来源特征尖喙牻牛儿苗、多型大蒜芥、沙漠绢蒿、碱蓬水分来源主要集中在 8-65 cm 土层土壤水,主要利用的水分土层仍存在一定的差异,沙漠绢蒿及碱蓬土壤水分利用季节变化明显。5 月,生长于空地的碱蓬主要水分来源集中于 0-10 cm 土层土壤水,土壤水利用平均深度为 8.43 cm,至 8 月,主要利用土壤水分深度明显向下移动,集中利用 30-100 cm 土层土壤水,对土壤水利用的平均深度为 41.2 cm。生长于空地的沙漠绢蒿与碱蓬,5 月主要利用的水源集中于 20-40 cm 土层,土壤水平均利用深度为 22.3cm,57.6 cm,8 月主要利用的土壤水分深度上升,集中于 0-20 cm 土层土壤水,平均利用深度为 12.2 cm。尖喙牻牛儿苗、多型大蒜芥、沙漠绢蒿、碱蓬利用土壤水的平均深度都浅于梭梭,5 月,碱蓬利用土壤水的平均深度最浅,多型大蒜芥对土壤水的平均利用深度最深。梭梭不影响多型大蒜芥水分利用特征;5 月尖喙牻牛儿苗与沙漠绢蒿及 8 月碱蓬土壤水分利用情况受梭梭影响较小;5 月碱蓬以及 8 月沙漠绢蒿土壤水分利用受梭梭影响较大。空地尖喙牻牛儿苗、多型大蒜芥、沙漠绢蒿、碱蓬之间不存在土壤水分竞争关系;冠下多型大蒜芥、沙漠绢蒿、碱蓬三者之间存在土壤水分竞争关系。 |
Subject Area | 自然地理学 |
Language | 中文 |
Document Type | 学位论文 |
Identifier | http://ir.xjlas.org/handle/365004/14871 |
Collection | 研究系统_荒漠环境研究室 |
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 | 傅思华. 古尔班通古特沙漠南缘梭梭群落水分来源[D]. 新疆乌鲁木齐. 中国科学院大学,2017. |
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