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题名	热脉冲法对塔里木盆地阿拉尔灌区胡杨耗水特性的研究
作者	白云岗
学位类别	硕士
答辩日期	2005
授予单位	中国科学院．中国科学院新疆生态与地理研究所．自然地理．
导师	宋郁东，中国科学院新疆生态与地理研究所
关键词	胡杨
其他题名	A study on water consumption characters of Populus euphratica in tarim basin by heat-pulse technique
中文摘要	水资源的科学合理配置与使用是干旱区社会经济可持续发展的基础。自然生态系统所需生态水资源量的定量研究是协调社会经济发展与维持区域自然生态系统稳定的前提。干旱区自然生态植被系统的耗水量研究将为我国西北地区经济的可持续发展、自然生态保护以及水资源可持续利用提供科学决策依据。因此，研究干旱区的主要造林树种胡杨的蒸腾变化规律、建立蒸腾的预报模型，具有重要的理论意义和实用价值。本文利用较为先进的热脉冲技术、中子仪水分测定系统同步监测胡杨的蒸腾液流、土壤水分动态因子，研究了热脉冲对胡杨树干液流的响应规律，分析了胡杨液流的变化规律和其主要影响因子的关系，并从理论分析着手建立二种类型的胡杨蒸腾模型，还用试验结果进行了验证，最后在单木液流测定的基础上，采用边材面积作为纯量，对胡杨林进行由单木到林分耗水的推算。研究结果表明：热脉冲能很好地响应胡杨树干液流的变化，单位时间内液流量变化呈明显的昼夜节律，白天的流速变化曲线呈双峰型，夜间树千液流速度处于平稳的低值，白天10：00左右达到峰值，午后18：00左右又达到一个峰值。不同胸径的胡杨在一天中树干液流动态变化规律基本一致，液流流速呈现双锋状态，但不同胸径的树干液流速度有很大差异，胸径大的要高于胸径小的树干。在正常生长状态下，不同区域、立地条件、个体、林种的胡杨耗水量差异十分显著。试验区内的土壤含水率随着时间变化而逐渐减小，其全部消耗于棵间蒸发和树体蒸腾，当胡杨林地郁闭度达到最高时，林地耗水以蒸腾为主，蒸腾接近蒸散的96％，棵间蒸发仅0.3mm／day。影响蒸腾的主要环境因子有净辐射、风速、气温和空气湿度、土壤水分等。通过斜率关联度的分析，气象因素对胡杨蒸腾量的影响程度从大到小的排列顺序为风速、气温、相对湿度、水面蒸发、水汽压。胡杨蒸腾随着气温、水汽压、土壤含水量的增大而增大，随着空气湿度的升高而减小，而风速比较特殊，当风速较小时，蒸腾是随着风速增大而增大，但到一定风速后，蒸腾量是随着风速的增大而减小的。利用实测的资料对建立的胡杨蒸腾分析，经验模型，相对误差平均值为4.67％，最大相对误差为13.33％。半经验模型相对误差平均值为3.61％，最大相对误差为12．09％。'表明使用上述计算方法得到的计算值与实测值相差较小，说明该方法是可行的，计算精度是可靠的。胡杨蒸腾模型中，半经验公式较为理想，经验公式不能揭示物理意义上的蒸腾过程，其精度也低于半经验公式。半经验公式考虑了长时间胡杨叶面积指数的变化，其也不能完全揭示物理意义上的蒸腾过程。但不论经验模型或半经验模型，均能利用常规气象资料较好地预测胡杨蒸腾耗水量。在单木液流测定的基础上，采用边材面积作为纯量，对胡杨林进行由单木到林分耗水的推算。结果表明，胡杨边材面积与胸径之间存在较高的相关性，两者之间的关系可以用幂模型得到很好的拟合。通过实测标准地的胸径分布，可以推算出林地边材面积的分布，利用热脉冲技术测定单木液流通量，可实时推算林分的实际耗水量。The scientific and rational allocation of water resources in arid and semi-arid area is the base of the sustainable development of social economy. The quantificational research on the water requirement of natural ecosystem is the precondition of the harmonization between social economy development and the stabilization of natural ecosystem. The research on water consumption of natural vegetation systems in arid and semi-arid area will provide scientific decision criterions on the sustainable development of social economy, natural ecosystem protection and the sustainable utilization of water resources in arid and semi-arid area of Northwest of China. Therefore, studying on Poputus euphrtuicr transpiration variety law and setting up a model for Poputus euphrtuicr transpiration prediction, have important theory meaning and practical balue. In this study, advanced heat-pulse technology, neutron probe are employed to determine the Poputus euphrtuicr sap flow, soil moisture. Law of heat pulse response to Poputus euphrtuicr stem sap flow is investigated. At the same time two types model of Poputus euphrtuicr transpiration are built on the base of theory analysis, and validated by experimentation result. And the stand daily water use for transpiration was estimated by heat-pulse technology and sapwood area as scalars to scale up based on individual tree measurement. Results as following: The diurnal variation of stem sap flow, the variation of sap flow with different diameters of cross section and the variant characteristics of stem sap flow in different area were investigated. The results show that, in the natural conditions, the intensity of sap flow of Populus euphrtaicr was 0.336L'cm' -d . During the growth season form April to August, the water consumption of Populus euphrtaicr is 56.11L-d1.The diurnal variation of sap flow shows dual-peaks characteristics, and it has the peak at 12:00 and 16:00. The amount and stem sap flow increase with the cross section of the plants. Sap flow of Populus euphrtaicr shows obvious difference in different area, individual and woodland. The diurnal change of volume of sap flow showed minor fluctuations closely related to the change- of micrometeorological factors. Results of the statistical analysis by grey correlative degree showed that wind speed, temperature of atmosphere are the main factors affecting the sap flow, and relative humidity, water vapor pressure have less effect on it. Moreover, it established the mathematical model being verified by the data of actual measurement. Among the transpiration models of Populus euphrtuicr, semi-experiential model is the most ideal. In this article, sapwood area is used as a scalar to extrapolate the stand water use from whole tree water use measured by heat-pulse technique. A significant correlation between sapwood area and diameter at breast height was found. The predication model is well fitted by power model. On the basis of the prediction model, sapwood area can be calculated by heat-pulse technique. The sap flow density can be used to extrapolate stand water use by a series of mathematical models.
语种	中文
学科主题	林学
公开日期	2010-11-12
页码	共47页
内容类型	学位论文
源URL	[http://ir.xjlas.org/handle/365004/8190]
专题	新疆生态与地理研究所_中国科学院新疆生态与地理研究所(2010年以前数据)
推荐引用方式 GB/T 7714	白云岗　. 热脉冲法对塔里木盆地阿拉尔灌区胡杨耗水特性的研究[D]. 中国科学院．中国科学院新疆生态与地理研究所．自然地理．. 2005.

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