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Institute of Botany, Chinese Academy of Sciences (2001)

A Study on Response of Dominant Plants to Global Climate Change in Maowusu Sandland

XiaoChunWang

Titre : A Study on Response of Dominant Plants to Global Climate Change in Maowusu Sandland

Auteur : Xiao Chun Wang

Grade : Doctoral Dissertation 2001

University  : Institute of Botany, Chinese Academy of Sciences

Résumé
Mu Us Sandland is a semi-arid region typical sandy, arid ecosystems here have a very sensitive response to changes in the pattern of the world’s water with hot. With the future of global climate change, such as temperature and precipitation changes, will give a tremendous impact on terrestrial ecosystems distribution pattern and productivity as well as water balance. This paper manual control 157.5mm, 315.0mm, 472.5mm and 630.0mm 4 of water supply and 25/20 ℃ and 28/23 ℃ (day / night) at two temperatures, to study and simulation Mu Us Sandland dominant plants of moisture and response to changes in temperature. Salix, Yang Chai and the oil of Artemisia seedlings for the study, artificial to control four kinds precipitation levels to explore the response of the water balance of global change in precipitation changes. The results show that with the increase in the water supply, sandy water volume and the amount of change, humidity, evaporation and transpiration quantity gradually increases. And the phenomenon of 157.5mm and 315.0mm measures the amount of water the plant sandy water deficit. The same water supply, the sandy water storage capacity and humidity Yang Cai Saudi> All Salix Saudi> oil Artemisia sand, the plant transpiration oil Artemisia> Salix> Hedysanm. Salix and oil of Artemisia seedlings for the study, artificial to control four kinds precipitation levels to explore the response of plant gas exchange process of global change in precipitation changes. The results show that the increase in water supply significantly increased net photosynthetic rate of two plants, transpiration rate, stomatal conductance and light use efficiency, and significantly reduces leaf temperature. Meanwhile, 157.5mm of water supply has caused the Salix and oil of Artemisia net photosynthetic rate and transpiration rate significantly \Salix, firewood, oil of Artemisia and C.korshinskii seedlings as the research object, manually controlled the four kinds precipitation levels to explore plant chlorophyll fluorescence response to global change in precipitation changes. The results showed that the different water supply initial fluorescence of these species, the maximum fluorescence, variable fluorescence and PSII photochemical efficiency have a significant impact. 157.5mm water supply Salix, Yang Cai, oil of Artemisia and C.korshinskii 630.0mm of water supply Caragana microphylla photoinhibition phenomenon. -11 - Summary to Salix, firewood, oil of Artemisia and C.korshinskii seedlings as the object of study, manual control of the four kinds of precipitation levels to explore plant growth response to global change in precipitation changes. The results show that the increase in water supply Salix, oil of Artemisia and Hedysanm foliage morphology and biomass and so has a significant positive effect. And 157. smm and 630. The omm Water Supply GROWTH OF CARAGANA has a negative effect. Of Salix, Yang Chai and the oil of Artemisia root and shoot biomass ratio gradually decreases with the increase in water supply levels are different water oil Artemisia root and shoot biomass ratio between the difference was not significant. As the research object, the artificial control of two temperature levels to explore plant morphology, biomass and climate exchange characteristics of warming response to of Caragana, Yang Cai and oil Artemisia seedlings. The results indicate that the warming significantly increased C. korshinskii Hedysanm plant height, number of leaves, leaf area, biomass, net photosynthetic rate, transpiration rate and stomatal conductance, but significantly reduces the efficiency of water use. Warming oil Artemisia leaf number \\ leaf size, leaf area, biomass, transpiration rate and stomatal conductance did not significantly affect significantly improve tree height and net photosynthetic rate of the oil of Artemisia. Growth and physiological characteristics of Caragana, firewood and oil of Artemisia species were significantly different.

Mots clés : Global climate change Analog temperature and precipitation changes Mu Us Sandland Semiarid area Dominant plants Salix Hedysanm Oil of Artemisia Caragana intermedia Water balance The gas exchange process The chlorophyll fluorescent H light Form Biomass

Présentation (Dissertation topics)

Page publiée le 28 mars 2014, mise à jour le 22 septembre 2017