古尔班通古特沙漠短命植物的氮素吸收策略  

Nitrogen uptake strategies of short-lived plants in the Gurbantunggut Desert

作　　者：庄伟伟 侯宝林 ZHUANG Weiwei;HOU Baolin(Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology,Urumqi 830000,Xinjiang,China;Key Laboratory of Special Environment Biodiversity Application and Regulation in Xinjiang,Urumqi 830000,Xinjiang,China;Key Laboratory of Plant Stress Biology in Arid Land,Urumqi 830000,Xinjiang,China)

机构地区：[1]新疆特殊环境物种保护与调控生物学实验室,新疆乌鲁木齐830000 [2]新疆特殊环境物种多样性应用与调控重点实验室,新疆乌鲁木齐830000 [3]干旱区植物逆境生物学实验室,新疆乌鲁木齐830000

出　　处：《干旱区研究》2021年第5期1393-1400,共8页Arid Zone Research

基　　金：国家自然科学基金项目(41763009);新疆维吾尔自治区教育厅项目(XJEDU2018Y034)。

摘　　要：研究荒漠生态系统同一生活型植物对氮素的利用是否存在生态位分离,有助于深入了解荒漠植物的生存策略,更好掌握氮素对荒漠植物生存的影响。在古尔班通古特沙漠中,广泛分布着4种短命植物尖喙牻牛儿苗(Erodium oxyrrhynchum)、琉苞菊(Hyalea pulchella)、假狼紫草(Nonea caspica)和飘带果(Lactuca undulata),对4种荒漠短命草本植物在不同月份不同土层深度对不同形态氮素的吸收利用进行了研究。结果显示:(1)在不同土层深度,5月4种植物的氮素吸收速率均高于4月的氮素吸收速率;对于不同形态氮素的吸收速率,甘氨酸均低于硝态氮和铵态氮。(2)4月假狼紫草对硝态氮的回收率最高,可达52.3%;5月假狼紫草对铵态氮的回收率最高,可达90.7%。(3)琉苞菊对15N的吸收量低于其他3种植物。(4)4种短命植物不仅可以利用土壤无机氮,还可以有效利用土壤有机氮,且尖喙牻牛儿苗和飘带果对硝态氮有明显的吸收偏好。(5)在古尔班通古特沙漠生态系统中,短命生活型的植物对氮素的吸收能力有着差异和多元化的特点,且均可吸收土壤中的可溶性的有机态氮源。Investigation into whether there is ecological niche separation of nitrogen(N)utilization by the same living type of plants in desert ecosystems can help in elucidating the survival strategies of desert plants and the influence of N on the survival of these plants.In the Gurbantunggut Desert,four short-lived herbaceous plants-Erodium oxyrrhynchum,Hyalea pulchella,Nonea caspica,and Lactuca undulata-are distributed widely.The uptake of different forms of N by these four plants was investigated at different soil depths in different months.The findings revealed that the N uptake rates of all four species in May were higher than were those in April at different soil depths.As for the uptake rates of different forms of N,that of glycine was lower than that of both nitrate and ammonium N.The highest recovery of nitrate N was achieved by N.caspica in April,up to 52.3%.Meanwhile,the highest recovery of ammonium N was achieved by N.caspica in May,reaching 90.7%.The uptake of 15N by H.pulchella was lower than was that by the other three species.The four short-lived plants could efficiently utilize not only soil inorganic N but also soil organic N,and E.oxyrrhynchum and L.undulata displayed a significant preference for nitrate N uptake.The findings reveal that in the Gurbantunggut Desert ecosystem,short-lived plants have differential and diversified N uptake capacity and can all absorb soluble organic state N sources from the soil.

关 键 词：短命植物 同位素标记 氮吸收 古尔班通古特沙漠 

分 类 号：Q948[生物学—植物学]