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近几十年来,全球气候变化以及人类活动的加剧导致古尔班通古特南缘荒漠地区的降水与地下水位发生显著改变,这些改变必然导致荒漠植物用水策略的适应性变化。本实验以古尔班通古特沙漠南缘原始沙漠中建群种梭梭(Haloxylon ammodendron)为研究对象,从种子萌发起,对气象因子、梭梭地上高度、地下根系深度、生物量等进行了连续监测,直至梭梭完成定居,以期探明梭梭定居过程中的个体形态调整特征。结果表明:在遭遇干旱时,梭梭以同化枝凋落的形态调节方式有效地维持了根系供水与地上部分需水之间的平衡,保证了存活同化器官的光合能力;同时,梭梭以牺牲地上部分生长为代价将更多的光合产物转向根系,使得根系能够获得更多的水分保证其生长、生存。
In recent decades, global climate change and the intensification of human activities have led to significant changes in the precipitation and groundwater levels in the desert areas on the southern edge of the Gurbantunggut. These changes will inevitably lead to the adaptive changes in desert plant water use strategies. In this study, Haloxylon ammodendron was established in the pristine desert in the southern margin of the Gurbantunggut Desert. From the germination of the seeds, the meteorological factors, the aboveground height of Haloxylon ammodendron, the depth of underground roots, biomass, etc. were studied Continuous monitoring was performed until Haloxylon settled, with a view to ascertaining the morphological characteristics of Haloxylon ammodendron colonization. The results showed that in the event of drought, Haloxylon ammodendron litterfall morphology was effectively maintained by the root system of water supply and aboveground water demand balance, to ensure the survival of the assimilate organ photosynthetic capacity; the same time, Haloxylon at the expense of the ground Part of the growth at the expense of more photosynthetic products to the root system, making the root system to obtain more water to ensure its growth and survival.