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991.
宋昕旖聂瑾璐杨梦涵喻懋椿陶梁明冯虎元潘建斌 《应用与环境生物学报》2022,(6):1527-1533
Polygonum viviparum, which reproduces sexually and asexually, is widely distributed in the Qinghai-Tibet Plateau, and its reproduction strategies are very sensitive to changes in the environment. This study aimed to elucidate the effect of altitude on the photosynthetic characteristics and reproductive strategies of P. viviparum. This study was conducted to investigate the responses of photosynthetic, vegetative, and reproductive traits of P. viviparum populations along six altitudinal gradients in the eastern part of the Qilian Mountains in China. Our results indicated that, with increasing altitude, the net photosynthetic rate of P. viviparum showed an increasing trend, reaching its maximum value (14.39 μmol m–2 s–1) at 3 700 m above sea level. The transpiration rate showed an increasing trend, followed by a decreasing trend, and the intercellular CO2 concentration did not differ significantly between altitudes. With increasing altitude, the plant height and leaf area of P. viviparum showed a downward trend, the aboveground and underground biomass decreased, and the specific leaf area initially decreased and then increased. However, the leaf greenness index showed an upward trend, and the number of stomata in the upper and lower epidermis of leaves initially increased and then decreased. With increasing altitude, the proportion of inflorescence length per plant (the ratio of inflorescence length to plant height), the proportion of bulbil length per inflorescence (the ratio of bulbil length to inflorescence height), and the proportion of the number of bulbils per inflorescence (the ratio of the number of bulbils to the total number of flowers and bulbils) showed an increasing trend. Air temperature and light intensity are the major environmental factors affecting the photosynthetic characteristics and functional traits of P. viviparum. Thus, P. viviparum is exposed to more environmental stresses and obtains less energy when altitude increases, but it adapts to the harsh alpine environment by increasing the photosynthetic capability per unit area. With increasing altitude, P. viviparum populations may be sustained by investing less energy in vegetation and more in reproduction, especially asexual reproduction. © 2022 Science Press. All rights reserved. 相似文献
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为探究宏观因素对我国各区域驾驶人“路怒症”的影响,从经济发展、交通环境、气候状况和地域文化4个方面选取13项指标,采用熵值法赋权,构建我国区域路怒水平影响因素评价体系,对2019—2020年我国5座城市的驾驶人路怒水平进行分析和评价。研究结果表明:宏观因素对5座城市的路怒水平均有影响,而且城市之间路怒水平差异相对较大,总体呈现“北高南低”的空间分布特征,据此为各城市预防和控制路怒水平提出针对性建议,以促进城市交通安全发展。 相似文献
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