黑河下游荒漠植物黑果枸杞叶片性状特征及其盐分响应

Leaf traits of desert plant Lycium ruthenicum Murr. in the lower reaches of Heihe River in response to salinity

本文以黑河下游额济纳地区优势荒漠植物黑果枸杞(Lycium ruthenicum Murr.)的8个自然群落为研究对象,调查不同盐碱条件下叶片总含水量(TWC)、相对含水量(RWC)、干物质含量(LDMC)、比叶面积(SLA)、比叶体积(SLV)、叶片厚度(LT)、肉质化程度(Suc)、组织密度(LD)等8项叶片性状指标,分析种内性状分化变异特征及其性状之间、性状与土壤盐分之间的关系。结果表明:黑果枸杞各叶片性状值的变异范围为3.99%~20.33%,其中TWC最小,SLV最大,群落间叶片性状值表现出较小的分化变异特征;叶片性状SLA与LDMC和LD之间呈极显著负相关(P<0.01),SLV与LDMC呈极显著负相关(P<0.01)、与TWC呈极显著正相关(P<0.01)、与RWC呈显著正相关(P<0.05),LDMC与LD呈极显著正相关(P<0.01);群落表层土壤盐分(0~20 cm)与叶片LT、SLV、Suc、TWC均呈显著正相关(P<0.05),与RWC呈极显著正相关关系(P<0.01);SLA、SLV、LDMC可以作为反映黑果枸杞适应荒漠逆境的关键叶片性状,叶片性状与土壤表层(0~20 cm)盐分之间的关系反映了荒漠植物为适应土壤盐分变化形成的保水对策。

The leaf traits, such as total water content （TWC）, relative water content （RWC）, leaf dry matter content （LDMC）, specific leaf area （SLA）, specific leaf volume （SLV）, leaf thickness （LT）, leaf succulence （Suc）, leaf density （LD） under different saline conditions, were studied for 8 natural communities of dominant species of desert plant Lycium ruthenicum at the lower reaches of Heihe River in Ejina Area. The differentiation characteristics of intraspecific traits, the relationship among leaf traits, and the relationship of leaf traits and soil salt were also analyzed. The results showed that the variations of leaf traits ranged from 3.99% to 20.33%, in which TWC was the lowest, and SLV was the highest. The leaf traits among communities showed small variation. SLA showed significantly positive relationship with LDMC and LD （P〈0.01）; SLV was significantly negatively correlated with LDMC （P〈0.01）, and significantly positively correlated with TWC （P〈0.01） and RWC （P〈0.05）. LDMC was significantly positively correlated with LD （P〈0.01）. The surface soil salinity （0-20 cm） was positively correlated with LT （P〈0.05）, SLV （P〈0.05）, Suc （P〈0.05）, TWC（P〈0.05） and RWC （P〈0.01）. SLA, SLV, and LDMC were the key leaf traits reflecting adaptability of L. ruthenicum to desert stress. The relationships of leaf traits and surface soil salinity （0-20 cm） reflected the water conservation strategies formed by desert plants to adapt to soil salinity.