极端干旱区胡杨根系吸水模型的构建
文献类型：学位论文
| 作者 | 王玉阳 |
| 答辩日期 | 2017-05-01 |
| 文献子类 | 硕士 |
| 授予单位 | 中国科学院大学 |
| 授予地点 | 新疆乌鲁木齐 |
| 导师 | 陈亚鹏 |
| 关键词 | 塔里木河下游 胡杨 根系分布 根系吸水模型 The lower reaches of Tarim River Populus euphratica root distribution root water uptake models |
| 学位专业 | 理学硕士 |
| 英文摘要 | Roots(mainly <=2 mm in diameter) are the pathway for soil water uptake by plants, the uptake of water by roots directly control the physiological activities of the whole plant.Root water uptake models provide a mathmatical tool for quantiatively understanding this process,which is the basis of studying the source and consumption of water of the plant, besides, it is also a crucial part of some ecohydrological research modules. So,the construction research of root water uptake models in extremely arid region can provide reference for quantitative study of water source of Populus euphratica, and it is helpful to understand the water use strategy of Populus euphratica. This research provides scientific basis for the protection and restoration of Populus euphratica in the lower reaches of Tarim River.This research selected desert riparian forest vegetation Populus euphratica at the lower reaches of Tarim River as the research object,we establish monitoring plot far away from the river and near the river respectively at Kumutuge.At each plot, two Populus euphratica were selected, we used neutron probe to detect the dynamic changes of soil water content in root zone , and cross section excavation for fine root sampling , at the same time, we combined with the relevant meteorological data, soil texture data etc.., based on the framework of Feddes model to construct the root water uptake model of Populus euphratica . The main results of the study as follows:1. At the same plot, the soil water content in the root zone of Populus euphratica had the same characteristics in the vertical direction, but there was considerable difference between different plot. Because of the little precipitation in the lower reaches of Tarim River, the soil water supply and the transpiration rate of plants almost did not change in a short period of time. Therefore, in this study, the overall trend of soil moisture in the root zone of Populus euphratica during the monitoring period (20 days) did not change significantly with time.2. There were no fine root growth at the soil surface, the fine roots of Populus euphratica in the river and far away from the river began to appear in 40cm and 80cm soil respectively. And fine roots showed a consistent distribution characteristics, that is, no fine roots at the surface, with the increase of soil depth showed a single peak pattern of the first increase and then decrease. In the horizontal direction, there was no significant change in the distribution of fine roots within the range of 6m from Populus euphratica trunk at the both site (P>0.05). In the vertical direction, the maximum root length density and fine root densely distribution area were more shallow than that of the river.3. The soil water content is the most important factor determining the distribution of fine roots in the lower reaches of Tarim River, the absence of fine roots in the soil surface is due to the coupling effect of low water content and high salt content. Because of the limitation of soil water and salt, the soil organic matter, available nitrogen and PH have little effect on the distribution of fine roots.4. The compensation water uptake process is weak in model simulation. After removing the compensation term, we adjusted the models at both sites and established the root water uptake models of Populus euphratica .That is : |
| 学科主题 | 自然地理学 |
| 语种 | 中文 |
| 源URL | [http://ir.xjlas.org/handle/365004/14904]  |
| 专题 | 新疆生态与地理研究所_研究系统_荒漠环境研究室 |
| 作者单位 | 中国科学院新疆生态与地理研究所 |
| 推荐引用方式 GB/T 7714 | 王玉阳. 极端干旱区胡杨根系吸水模型的构建[D]. 新疆乌鲁木齐. 中国科学院大学. 2017. |
入库方式： OAI收割
来源：新疆生态与地理研究所
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