【作者】 朱艳艳；

【导师】 张府娥； 贺康宁；

【作者基本信息】 北京林业大学 ， 水土保持与荒漠化防治， 2007， 硕士

【摘要】 本文针对干旱半干旱地区植被建设中植被与水资源关系不协调的问题,以土壤-植物--大气连续系统(SPAC)理论为基础,选择几种主要的水土保持灌木柽柳(Tamarixramosissma Ledeb.)、小叶锦鸡儿(Caragana microphylla)和杨柴(Hedysarummongolicum Turcz)作为研究对象。在2006年的生长季期间,利用Li-6400便携式光合仪等仪器,分析不同水分环境条件和光照条件与林木生长的关系,系统地研究该地区几种主要灌木光合生理生态学特征,其结果不仅有助于干旱半干旱地区植被建设中生态用水定额的确定,而且也将对今后该地区植被建设中物种选择和合理林分密度设计起到科学的指导作用。本文主要开展了以下几方面的研究:1土壤水分对林木光合特性和水分利用效率的影响;2光辐射强度对林木光合特性和水分利用效率的影响;3不同水分条件下林木光合生理参数的日过程;经研究,结果表明:●柽柳、小叶锦鸡儿和杨柴的净光合速率(Pn)、蒸腾速率(Tr)和水分利用效率(WUE)的日变化,与土壤水分条件密切相关,并且有明显的阈值响应。三种灌木的凋萎湿度分别为1.09%、0.71%、0.68%。●对库布齐沙地几种主要灌木柽柳、小叶锦鸡儿和杨柴的光合速率、蒸腾速率、水分利用效率与土壤含水量的关系进行研究,初步了解了适宜这三种植物生长的土壤含水量。柽柳、小叶锦鸡儿和杨柴最适宜生长的土壤含水量范围分别为7.2%～10.1%、6.2%～11.0%和7.3%～9.9%。●光辐射强度的变化对柽柳、小叶锦鸡儿和杨柴的光合速率、蒸腾速率和水分利用效率都有显著影响。柽柳既具有较高的光能利用效率又具有较高的水分利用效率的光强范围在980-1500μmol·m-2·s-1;小叶锦鸡儿既具有较高的光能利用效率又具有较高的水分利用效率的光强范围在800～1800μmol·m-2·s-1;杨柴既具有较高的光能利用效率又具有较高的水分利用效率的光强范围在800～1500μmol·m-2·s-1。更多还原

【Abstract】 In ording to solve the contradiction between demand for the extension of forest vegetation andthe limited water supply in arid and semi-arid area and based on the theory of soil-plant-atmosphere continuum, the dissertation chose the main afforestation tree species including Tamarix ramosissma Ledeb Caragana microphylla and Hedysarum mongolicum Turcz .to forest project in Growing Seasons in 2006,utilized advanced apparatus, equipments and various approaches, systematically analyzed of relationship between soil water content and light intensity and growing and photosynthesis characteristics. These studies could provides the scientific bases for accurately estimating ecological water consumption and the choice of tree species and the properly arrangement of stand density. The dissertation involved following aspects:1: Study on reposing to light of Tamarix ramosissima Ledeb, Caragana microphylla and Hedysarum mongolicum Turcz in different soil moisture;2: Study on suitable water content of Tamarix ramosissima Ledeb, Caragana microphylla and Hedysarum mongolicum Turcz;3: Study on diurnal course of Tamarix ramosissima Ledeb, Caragana microphylla and Hedysarum mongolicum Turcz in different soil water content; By studying the result show that:The relation of diurnal course of photosynthetic rate（Pn） , transpiration rate（Tr） and water use efficiency of leaf （WUE） and soil water content is close, and response to SWC is obvious, withered moisture of three shrubs is separately 1.09%,0.71%,0.68%.Study on the relation among photosynthesis rate, stomatal conductance, transpiration rate, water use efficiency and soil water content. The result show the suitable water content of Tamarix ramosissima Ledeb is 10.1% ～ 13.6%, Caragana microphylla is 11.0% ～ 13.4%,and Hedysarum mongolicum Turcz is9.9%～15.0%.Photosynthetic rate, transpiration rate and water use efficiency of leaf have clear threshold value response to photosynthetic active radiation. the fitting sphotosynthetic active radiation cause higher sunshine use efficiency and water use efficiency of Tamarix ramosissima Ledeb is 980～1500μmol·m^-2·s^-1, the fitting sphotosynthetic active radiation cause higher sunshine use efficiency and water use efficiency of Caragana microphylla is 800～1800μmol·m^-2·s^-1, the fitting sphotosynthetic active radiation cause higher sunshine use efficiency and water use efficiency of Hedysarum mongolicum Turcz is 800～1500μmol·m^-2·s^-1.更多还原