北疆一年生早春短命植物物种丰富度分布格局及其影响因素  

Patterns and drivers of species richness of early spring annual ephemeral plants in northern Xinjiang

作　　者：王爱霞 马婧婧 龚会蝶 范国安 王茂 赵红梅 程军回[1,2] Aixia Wang;Jingjing Ma;Huidie Gong;Guoan Fan;Mao Wang;Hongmei Zhao;Junhui Cheng(College of Grassland and Environment Sciences,Xinjiang Agricultural University,Urumqi 830052;Xinjiang Key Laboratory of Soil and Plant Ecological Processes,Xinjiang Agricultural University,Urumqi 830052)

机构地区：[1]新疆农业大学草业与环境科学学院,乌鲁木齐830052 [2]新疆土壤与植物生态过程重点实验室,乌鲁木齐830052

出　　处：《生物多样性》2021年第6期735-745,共11页Biodiversity Science

基　　金：国家自然科学基金(31660127,31700423,31960260,U1603235)。

摘　　要：理解植物多样性变化的影响因素一直是群落生态学和生物地理学研究的重要内容。大量研究显示,植物多样性受到海拔、古气候、现代气候、土壤养分和地上生物量等一系列因素的影响。然而,很少有研究综合考虑这些因素对植物多样性的影响和相对重要性。本研究以北疆一年生早春短命植物为研究对象,以2017年和2018年对32个样地调查的物种丰富度为基础,通过一般线性模型和偏最小二乘通径模型分析了海拔、气候因素(年平均温度、冬季降水、2-5月降水以及末次冰期以来2-5月降水变化距平)、土壤养分(pH、土壤有机碳、全氮、全磷、碳氮比、碳磷比和氮磷比)和地上生物量与该类植物物种丰富度平均值的关系及其相对重要性。结果显示:(1)一年生早春短命植物物种丰富度与海拔、年均温度、2-5月降水、末次冰期以来2-5月降水变化距平、土壤pH、土壤碳氮比和地上生物量均呈现显著的单峰型关系,而与冬季降水之间表现为先降低后增加的变化趋势,表明该类植物多样性同时受到多种因素的影响;(2)海拔、气候因素和土壤养分不仅对该类植物物种丰富度存在显著的直接影响,也可通过改变地上生物量进而对其物种丰富度产生间接影响;(3)这些因素中,气候因素是影响一年生早春短命植物物种丰富度的最主要影响因素,其次分别为地上生物量、海拔和土壤养分。海拔、土壤养分、气候因素及地上生物量共同驱动了北疆地区一年生早春短命植物丰富度的变化。Aims:Identifying factors that determine plant diversity remains an important issue in community ecology and biogeography.Many studies have demonstrated that plant diversity is tightly associated with a suite of environmental factors,such as elevation,contemporary climate,paleoclimate,soil nutrient availability,and aboveground biomass(AGB).However,their effects and relative importance on plant diversity is still unknown due to lack of comprehensive study.Methods:To assess relative importance of elevation,contemporary climate,paleoclimate,soil nutrient availability and AGB on early spring annual ephemeral plant(s)(ESAE),we surveyed species richness of ESAE across 32 sites in 2017 and 2018 in northern Xinjiang.We used general linear models to explore relationships of mean species richness(SR)of ESAE with elevation,climate(including annual mean temperature,precipitation in winter,precipitation from February to May,and anomaly of precipitation from February to May since the Last Glacial Maximum),soil nutrient availability(pH,soil organic carbon(SOC),total nitrogen(TN),total phosphorus(TP),the ratio of SOC to TN(C:N);the ratio of SOC to TP(C:P),the ratio of TN to TP(N:P),and AGB.We then adapted partial least squares path modeling(PLS-PM)to measure the relative importance of each of these variables in regulating SR of ESAE.Results:We found that SR of ESAE exhibited a significant unimodal pattern with increasing elevation,annual mean temperature,precipitation from February to May,anomaly of precipitation from February to May since the Last Glacial Maximum,soil pH,C:N,and AGB,but a U-shaped pattern with increasing precipitation in winter.Elevation,climate,and soil nutrients availability could influence SR of ESAE by altering AGB either directly or indirectly.Among these factors,climate was the most important factor in regulating SR of ESAE,followed by AGB,elevation,and soil nutrient availability,respectively.Conclusion:Elevation,soil nutrients availability,climate and aboveground biomass had significant effects on species

关 键 词：海拔 气候因素 土壤养分 地上生物量 物种丰富度 一年生早春短命植物 

分 类 号：Q948[生物学—植物学]