三江源地区草地植物功能性状与蒸散发关系研究

Study on the Relationship between Functional Traits of Grassland Plants and Evapotranspiration in the Sanjiangyuan

蒸散发作为调控区域水分收支的重要支出项,受植物性状的影响。本研究于2021年5月—2021年9月对三江源及其周边共5个区域(海晏(HY)、同德(TD)、玛多(MD)、曲麻莱(QML)、可可西里(KKXL))的实际蒸散发及植被数据进行收集,通过相关性分析解释植被变化过程对环境的适应策略。结果表明:三江源草地植物多以丛生或密丛生为主,其中比叶面积与株高、叶片干物质含量、生长型和种子类型间呈显著负相关(P<0.05)。生长季实际蒸散发日、月动态在5个区域均呈现单峰变化趋势,生长季累积量为HY(309.97 mm)>TD(279.58 mm)>QML(247.90 mm)>MD(239.42 mm)>KKXL(230.35 mm)。分析植物功能性状与实际蒸散发之间的相关性,表明株高、比叶面积、叶片干物质含量、生长型和种子类型均与实际蒸散发呈现一定相关性,其中生长型相关性最大(R 2=0.74)。

Evapotranspiration is a key expenditure item in regulating the regional water budget and can affect the growth and traits of plants.Here,from May 2021 to September 2021,a total of 5 research sites in Sanjiangyuan and its surrounding areas(Haiyan(HY),Tongde(TD),Maduo(MD),Qumalai(QML),Hoh Xil(KKXL)),were investigated on the vegetation traits to explain the adaptation strategies of plants to the environment.The results showed that:the plants in Sanjiangyuan are mostly clustered or densely clustered,and there was a significant negative correlation between specific leaf area and plant height,leaf dry matter content,growth type and fruit(P<0.05).The actual daily and monthly dynamics of evapotranspiration showed a single-peak trend in the 5 research sites during the growing season,the accumulation in the growing season were HY(309.97 mm)>TD(279.58 mm)>QML(247.90 mm)>MD(239.42 mm)>KKXL(230.35 mm).The correlation between plant functional traits and actual evapotranspiration was analyzed,and the results showed that plant height,specific leaf area,leaf dry matter content,growth form and fruit all had a certain correlation with actual evapotranspiration,among them the growth form had the greatest correlation(R 2=0.74).