张掖湿地芦苇比叶面积和水分利用效率的关系  

Relationship analysis between specific leaf area and water use efficiency of Phragmites australis in the Zhangye wetland

作　　者：李群[1] 赵成章[1] 王继伟[1] 赵连春[1] 徐婷[1] 韩玲[1] 

机构地区：[1]西北师范大学地理与环境科学学院甘肃省湿地资源保护与产业发展工程研究中心,兰州730070

出　　处：《生态学报》2017年第15期4956-4962,共7页Acta Ecologica Sinica

基　　金：国家自然科学基金(41461013;91125014)

摘　　要：密度制约下植物比叶面积与水分利用效率的关系,对于认识土壤-植物-大气的物质循环和能量流动机制具有重要意义。采用样方调查法,研究了3种密度(高密度Ⅰ:210—230株/m^2;中密度Ⅱ:130—150株/m^2;低密度Ⅲ:50—70株/m^2)条件下芦苇种群比叶面积(SLA)和水分利用效率(WUE)的关系。结果表明:随着芦苇种群密度的逐渐降低,湿地群落的土壤含水量逐渐减小,芦苇的株高、叶面积、叶干重、SLA和蒸腾速率(Tr)均呈逐渐减小的趋势,净光合速率(Pn)、叶厚度和WUE呈逐渐增加的趋势;不同密度条件下湿地植物芦苇比叶面积(SLA)与水分利用效率(WUE)的关系存在显著差异(P<0.05),在高密度(Ⅰ)与低密度(Ⅲ)样地,芦苇SLA与WUE呈极显著负相关关系(P<0.01);在中密度(Ⅱ)样地,二者呈显著负相关关系(P<0.05)。不同种群密度的湿地生境中,芦苇通过调整叶片形态构造,使比叶面积和水分利用效率形成了相反的变化趋势,反映了植物适应光照条件、土壤含水量等异质性环境因子的资源利用策略和光合产物积累模式。Abstract： Study of the relationship between plant specific leaf area （SLA） and water use efficiency （WUE） under different density conditions is necessary to understand the mechanisms of material circulation and energy flow through the soil, plants, and atmosphere. There were three main goals in this study ： （ 1 ） , to determine the relationship between plant SLA and WUE; （2）, to analyze whether the relationship is variant along a gradient; and （3）, to explain the causes of the relationship. The study site was located in the national wetland park conservation areas in Zhangye city, Gansu Province, China （100-26′50.72″E, 38-58′42.9″N）. The study area began at the lakeside and extended to the central section of the lake island, gently transiting through the wetland community, in which the common reed （Phragmites australis ） was the single dominant species. The reed community was divided into 3 levels based on density, with a ＂bundle＂ torming the sampling unit ： Low density （III, 50-70 bundle/m^2） , medium density （II, 130--150 bundle/m^2） , and high density （ 1, 210-230 bundle/m^2）. Next, using a zigzag order from bottom to top, six （2 m× 2 m） reed samples were selected per density, for an overall total of 18 samples （3 - 6）. Then, community traits （height and density） and soil moisture were determined and 12 individuals of P. australis were taken to the laboratory to measure the leaf thickness. In addition, the leaf net photosynthetic rate （Pn） and transpiration rate （Tr） of the reeds were measured in each plot. Quadrat survey methodswere used to determine the relationship between the specific leaf area and water use efficiency of the reeds under three density conditions. The results indicated that, as population density decreased from high, to lower, the wetland community soil moisture content gradually decreased, as well as reed height, leaf area, leaf dry biomass, SLA, and transpiration rate （Tr）. However, the net photosynthetic r

关 键 词：芦苇 比叶面积 水分利用效率 张掖湿地 密度制约 

分 类 号：Q948[生物学—植物学]