Temperature response of C4 species big bluestem (Andropogon gerardii) is modified by growing carbon dioxide concentration
Temperature response of C4 species big bluestem (Andropogon gerardii) is modified by growing carbon dioxide concentration
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DOI：
10.1016/j.envexpbot.2007.06.002
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发表时间：
2007-12-01
影响因子：
5.7
通讯作者：
Reddy, K. Raja
中科院分区：
文献类型：
--
作者：
Kakani, V. G.;Reddy, K. Raja
气候变化因素相互作用，改变植物的生长和发育。本研究的目的是评估在受控环境条件下生长的低和高二氧化碳浓度 ([CO2]) 下大须芒草 (Andropogon gerardii Vitman) 发育、生长、繁殖和生物量分配对温度的响应。使用十个阳光照射的土壤植物大气研究（SPAR）室来研究低（360μLL-1）和高（720μLL-1）两种[CO2]以及五种不同的昼/夜温度（20/12、25/17、30/22、35/27和40/32摄氏度）的影响。将 Bonelli 种子播种在纯净的细沙中，等间距种植 11 行，出苗后间苗至每行 10 株。成熟时，收获单株植物并分为叶、茎、颗粒和根。在高于或低于 30/22 摄氏度的最佳温度时，生物量都会减少。高 [CO2] 对生物量积累的影响（增加 12-30%）在低于最佳温度（30/22 摄氏度）时可见，而在两个高温下则不存在。随着温度升高，无论[CO2]如何，分配到叶子的生物量增加（35%），而分配到茎的生物量减少（33%）。在 25/17 摄氏度时，颗粒重量为生物量的 6-7%，在 40/32 摄氏度时降至 1.6%。在不同温度下，分配到根部的生物量对于在低 [CO2] 下生长的植物来说是恒定的，但对于在高 [CO2] 下生长的植物来说则减少了 7%。两次高温（> 30/22 摄氏度）下穗/种子产量的减少可能会减少该物种的数量和在高草草原的优势地位。不同[CO2]下的温度响应函数将有助于提高动态全球植被模型在模拟牧场动态时的预测能力，其中大须芒草是优势物种。 (C) 2007 Elsevier B.V. 保留所有权利。
Climate change factors interact to modify plant growth and development. The objective of this study was to evaluate the response to temperature of big bluestem (Andropogon gerardii Vitman) development, growth, reproduction and biomass partitioning under low and high carbon dioxide concentrations ([CO2]) grown in controlled environmental conditions. Ten sunlit soil-plant-atmosphere-research (SPAR) chambers were used to study the effects of two [CO2] of low (360 mu LL-1) and high (720 mu LL-1), and five different day/night temperatures of 20/12, 25/17, 30/22, 35/27 and 40/32 degrees C. Big bluestem cv. Bonelli seeds were sown in pure, fine sand, in 11 rows at equal spacing and after emergence were thinned to 10 plants per row. At maturity, individual plants were harvested and divided into leaves, stems, particles and roots. Biomass decreased either above or below the optimum temperature of 30/22 degrees C. The effect of high [CO2] on biomass accumulation (12-30% increase) was visible at less than optimum temperature (30/22 degrees C) and absent at two high temperatures. With increase in temperature, irrespective of the [CO2], biomass partitioned to leaves increased (35%) where as that to stems decreased (33%). Particle weight was 6-7% of biomass at 25/17 degrees C and fell to 1.6% at 40/32 degrees C. The biomass partitioned to roots, across the temperatures, was constant for plants grown at low [CO2] but decreased by 7% for those grown at high [CO2]. The decrease in panicle/seed production at two high temperatures (>30/22 degrees C) might reduce this species population and dominance in tallgrass prairies. The temperature response functions at different [CO2] will be useful to improve the predictive capabilities of dynamic global vegetation models in simulating dynamics of rangelands, where big bluestem is the dominant species. (C) 2007 Elsevier B.V. All rights reserved.