元江干热河谷低海拔地带退化生态系统植物多样性及物种分布模式  

Biodiversity and Species Distribution in a Declined Ecosystem in the Lowland of Yuanjiang Dry-hot Valley

作　　者：杨逢春 刘景欣[2] 黄华平[3] 构箭勇 文慧婷 李叶[3] 陈娴 KRITANA Prueksakorn HONG Anh Thi Nguyen CHAYA Sarathchandra YANG Fengchun;LIU Jingxin;HUANG Huaping;GOU Jianyong;WEN Huiting;LI Ye;CHEN Xian;KRITANA Prueksakorn;HONG Anh Thi Nguyen;CHAYA Sarathchandra(Yibin Vocational and Technical College,Yibin,Sichuan 644003;Environmental Education Center,Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences,Mengla,Yunnan 666302;Environment and Plant Protection Research Institute,Chinese Academy of Tropical Agricultural Sciences,Haikou 570100;Honghe Meteorological Bureau,Mengzi,Yunnan 661100;International Education Hub for Innovation,Social Engagement and Sustainable Development,Prince of Songkla University,Phuket,Thailand 83000;State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-environmental Sciences,Chinese Academy of Sciences,Beijing 100085;Department of Biological Science,Faculty of Applied Sciences,Rajarata University of Sri Lanka,Mihintale,Sri Lanka 50300)

机构地区：[1]宜宾职业技术学院,四川宜宾644003 [2]中国科学院西双版纳热带植物园环境教育中心,云南勐腊666302 [3]中国热带农业科学院环境与植物保护研究所,海口570100 [4]云南省红河哈尼族彝族自治州气象局,云南蒙自661100 [5]宋卡王子大学国际教育创新,社会参与和可持续发展中心,泰国普吉83000 [6]中国科学院生态环境研究中心城市与区域生态国家重点实验室,北京100085 [7]斯里兰卡拉贾拉塔大学应用科学学院生物科学系,斯里兰卡密亨塔勒50300

出　　处：《中国农学通报》2021年第36期87-96,共10页Chinese Agricultural Science Bulletin

基　　金：宜宾职业技术学院高层次人才科研启动金项目(ybzysc20bk03);宜宾职业技术学院科研平台(ybzy21kypt-05);宜宾职业技术学院科技创新团队建设计划(ybzy21cxtd-04);竹类病虫防控与资源开发四川省重点实验室开放研究课题(ZLKF20-02);四川省社会科学重点研究基地彝族文化研究中心资助项目(YZWH2101)。

摘　　要：元江干热河谷是一个低海拔的脆弱生态系统,以环境干旱、植被贫乏为主要特征。17世纪中期以前它曾经植被茂盛,但是17世纪末以后,它逐渐演变退化为一个典型的热带山地萨王纳类型。本研究旨在阐明元江干热河谷低海拔地带典型干热区植物的多样性及其分布状况,从而深入了解气温、降水、地下水等主要的环境因子对植物种类及种群的影响以及植物对干热环境的适应,以及植物种类及其组成对元江干热河谷环境的指示作用。考察的主要指标包括物种多样性α,生境多样性β,物种期望值Species_estimated,稀有指数Singletons和Uniques,以及物种丰富度指数ACE、ICE和Chao2等。结果显示:(1)在不同的样带设计中,以紧靠河流的样带和样方(<25 m)α多样性高,远离河道则逐渐变小。(2)在平行于河道的L样带,随着沿河流从上游向下游延伸,β多样性变化趋势明显,Bray-Curtis<0.500;而在垂直于河道的P样带,随着环境干热化加剧及河道渗水的急剧减少,生境趋同性明显,Bray-Curtis>0.500。(3)总体趋势上,干热河谷低海拔地带的植物对水分的依赖性表现得相当明显,在紧靠河道的样带,以及河流下游河漫滩发育地区,物种期望值Species_estimated、稀有种指数Singletons和Uniques以及物种丰富度指数ACE,ICE和Chao2都明显偏高。本研究研究证明干热河谷低海拔地区存在特殊水热条件,影响植物的种类和分布,同时阐明了干热河谷低海拔地区植物多样性及种类分布与河道周边的小生境密切相关,为脆弱生态环境环境变化监测提供建议。Yuanjiang dry-hot valley is a poorly vegetated and fragile arid ecosystem in low land.Although it was lushly forested before the middle of the17^(th) century,it became a tropical montane savannah after the end of the 17^(th) century.This study focuses on the diversity and distribution patterns of plants in this representative xerophytic flora,aiming to explain the impact of main environmental factors such as temperature,precipitation and underground water supply on species and populations,so as to explore the adaptation of plants.Furthermore,dry-hot environment indications corresponding to species and species assemblage were considered.Therefore,alpha and beta indices were employed to cope with biodiversity differences in plant species and its environment,respectively.Selected indices were subscribed to the relationship among species,population size,and their living circumstances in terms of Species_estimated,Singletons,Uniques,ACE,ICE,and Chao2.The results show that:(1)alpha diversity is higher in the transects and plots closing to the river channel(<25 m),and decreases away from the riverway;(2)beta diversity increases from upper to lower stream in L-transect(Bray-Curtis<0.500),however,it is reversed in P-transect,the homoplasy is obvious(Bray-Curtis>0.500);(3)in the lowland of dry-hot valley,indices of Species_estimated,Singletons,Uniques,ACE,ICE,and Chao2 are significantly high beside river especially in the tidal range,which indicates a strong reliance on water supply.Conclusively,species composition and distribution patterns in the lowland of Yuanjiang dry-hot valley are deeply affected by heterogenity of water and temperature allocation.Plant species and their diversity are closely correlated to the microhabitat along river channel,and this correlation could be an approach for environmental monitoring potentially.

关 键 词：元江干热河谷 低海拔地带 生物多样性 物种分布 指示种 元江-红河 

分 类 号：Q948.11[生物学—植物学]