荒漠草本植物在不同降雨模式下的光合响应和生物量分配策略  

Photosynthetic responses and biomass allocation strategies of desert herbaceous plants under different precipitation patterns

作　　者：吴玉[1,2,3] 郑新军[1,3] 李彦[1,3] 唐立松[1,3] 

机构地区：[1]中国科学院新疆生态与地理研究所,荒漠与绿洲生态国家重点实验室,新疆乌鲁木齐830011 [2]中国科学院大学,北京100049 [3]中国科学院阜康荒漠生态系统研究站,新疆阜康831500

出　　处：《生态学杂志》2013年第10期2583-2590,共8页Chinese Journal of Ecology

基　　金：国家重点基础研究发展计划项目(2009CB825102);国家自然科学基金项目(41171049);西部之光西部博士项目(XBBS201001)资助

摘　　要：植物对降雨格局变化的响应和适应影响着生态系统碳固定等过程。本研究在盆栽控制条件下,以4种荒漠草本植物地肤(Kochia scoparia)、滨藜(Atriplex patens)、盐角草(Salicornia europaea)和短柱猪毛菜(Salsola lanata)为对象,设置4种降雨模式处理(湿润处理20 mm×1/周与10 mm×2/周;干旱处理12 mm×1/周与6 mm×2/周),分析其净光合速率(P_n)、植物PSII最大光化学效率(F_v/F_m)随时间的变化,以及植株的生物量分配情况。结果表明:各处理下,P_n基本都在降雨后第2天达到峰值,并且植株能维持较高的单叶P_n;盐角草和短柱猪毛菜的F_v/F_m在各处理下均处于最适范围。比叶面积(SLA)和比根长(SRL)受降雨处理影响不显著。地肤生长主要受P素限制,其他3种植物主要受N素限制。降雨量主导着植物总生物量和叶茎根各部分生物量,降雨频次能调节植物地上和地下部分生物量分配的比例。等水量下,降雨频次增多使植物加大地下生物量的分配。The responses and adaptation strategies of plants to the variations of precipitation pattern can affect the ecosystem processes such as carbon sequestration. In this paper, a pot experiment was conducted to study the variations of the net photosynthetic rate （Pn）, maximum photochemical efficiency of PSII （Fv/Fm）, and biomass allocation of four desert herbaceous plants （Kochia scoparia, Atriplex patens, Salicornia europaea, and Salsola lanata） under four simulated precipitation patterns （wet treatments 20 mm × 1 per week versus 10 mm ×2 per week, and drought treatments 12 mm × 1 per week versus 6 mm × 2 per week）. Overall, the Pn of the plants peaked on the 2nd day after the treatments, and the plants maintained a higher level of single leaf Pn. The Fv/Fm of S. europaea and S. lanata in all treatments was kept within an optimal range. The specific leaf area （SLA） and specific root length （SRL） were less affected by the treatments. The growth of K. scoparia was limited by phosphorus, while that of the other three species was limited by nitrogen. The precipitation amount dominated the total biomass and the leaf, shoot, and root biomass, whereas the precipitation frequency regulated the biomass allocation in plant above and belowground parts. Under a given precipitation amount, the increase of precipitation frequency promoted more biomass allocation in plant belowground part.

关 键 词：降雨模式 净光合速率 植物PSⅡ最大光化学效率 生物量分配 植物性状 

分 类 号：Q948[生物学—植物学]