准噶尔盆地南缘小叶桦种群急速退化原因及保护对策  

Causes of rapid degradation of Betula microphylla population in the southern margin of Junggar Basin and protection strategies

作　　者：王玉霞 刘佳敏 杜珍珠[1,2] 徐文斌 马占仓[1] 黄刚 阎平[1] WANG Yuxia;LIU Jiamin;DU Zhenzhu;XU Wenbin;MA Zhancang;HUANG Gang;YAN Ping(College of Life Science,Xinjiang Production and Construction Corps Key Laboratory of Oasis Town and Mountain-basin System Ecology,Shihezi University,Shihezi 832003,China;Laboratory Equipment Department,Shihezi University,Shihezi 832003,China)

机构地区：[1]石河子大学生命科学学院/绿洲城镇与山盆系统生态兵团重点实验室,石河子832003 [2]石河子大学分析测试中心,石河子832003

出　　处：《生态学报》2024年第18期8294-8303,共10页Acta Ecologica Sinica

基　　金：新疆小叶桦遗传多样性及其濒危机制研究(32160317);石河子大学自主资助科研项目(ZZZC201930B)。

摘　　要：为查明准噶尔盆地南缘蘑菇湖湿地小叶桦种群急速退化原因,进行了该种群退化因子相关调查,计算了植物群落的多样性指数,对叶片和土壤化学计量特征进行了相关性分析,利用SLAF-seq技术对小叶桦种群遗传差异做了比较。结果表明:(1)该种群现仅132活株,相比2013年减少86.34%,现死亡植株75.91%,表明该种群遭到严重破坏;(2)2013年该群落植物分属于36科80属119种,现23科40属47种,群落Shannon多样性指数由1.5降至1.14,均匀度指数从0.21降到0.16,植物多样性和均匀度减低破坏根系保护屏障,降低其抵抗极端气候的能力;(3)土壤PH均值6.98为偏中性土壤,土壤全氮、全磷、全钾的平均含量分别为125.08g/kg、13.25g/kg、9.16g/kg,土壤肥力能满足小叶桦生长需求,但土壤含水量仅21.39%,与艾比湖小叶桦种群(48.44%)相比明显减少,土壤含水量减少弱化幼苗更新机制也是导致该种群退化的主要因素之一;(4)人为干扰和自然灾害因素也是野生极小种群形成和发展过程中不可忽略的重要因素;(5)该种群相较之艾比湖保护区种群单核苷酸多态性位点杂合度较高、多态性和完整度较低,生境退化导致的遗传衰退现象已显现。综上表明,影响该小叶桦种群急速退化原因涉及多方面,急需主管部门采取对策挽救该种群免遭灭绝的风险。研究成果为该地区的植被恢复和开展保护行动提供科学依据。The reasons for the rapid degradation of the Betula microphylla population in the mushroom lake wetland on the southern margin of the Junggar Basin remain unclear.To investigate the various factors of the degradation,plant diversity and related indices were calculated based on data.Relationships of stoichiometric characteristics between plant leaves and soils were presented through correlation analysis,genetic differences were then analysed across the SLAF-seq technology.The results showed that(1)there were only 132 live plants,a decrease of 86.34%compared with 2013,and 75.91%of the dead plants,indicated that the population was extremely damaged.(2)In terms of plant community composition,compared with 2013,there were 119 species in 80 genera and 36 families,but now there are only 47 species in 40 genera and 23 families.Shannon diversity index of the community decreased from 1.5 to 1.14,followed by Pielous index from 0.21 to 0.16.The drop of plant diversity and Evenness index indirectly damaged root protection barrier and its ability to resist extreme weather began to decline.(3)The average soil pH value was 6.98,neutral soil;average contents of total nitrogen,total phosphorus and total potassium were 125.08 g/kg,13.25 g/kg,and 9.16 g/kg,respectively,and the soil fertility could meet the growth needs of B.microphylla;The soil water content was 21.39%,which was significantly lower than the Ebinur Lake B.microphylla population(48.44%);The decrease of soil water content weakened the seedling regeneration mechanism,which was also one of the main factors leading to the degradation of this population.(4)Human disturbance and natural disaster factors could not be ignored in the formation and development of wild minimal populations.(5)The heterozygosity of the SNP(single nucleotide polymorphism)sites in this population was higher,SNP polymorphism and integrity was lower than Ebinur Lake Reserve population,and the phenomenon of genetic decline due to habitat degradation had been shown.In conclusion,the rapid degradation of

关 键 词：湿地 小叶桦 退化 保护 

分 类 号：Q948[生物学—植物学]