广西科学院学报2023，Vol.39Issue(4)：393-402,10.DOI:10.13657/j.cnki.gxkxyxb.20231226.006
尾巨桉人工林主要生态效应研究
Main Ecological Functions of Eucalyptus urophylla×E.gran-dis Plantation
摘要
Abstract
To unveil the interplay between the Eucalyptus urophylla×E.grandis plantations and the ecologi-cal environment,and to objectively assess the ecological functions of the E.urophylla×E.grandis planta-tions,this study relies on the Nanning Eucalyptus Forest Ecosystem Guangxi Wild Field Scientific Observa-tion Research Station and the Zhanjiang Eucalyptus Forest Ecosystem National Positioning Observation Re-search Station.With the E.urophylla×E.grandis plantations as the research subject,the study observes the transpiration of individual trees,stand evapotranspiration,and root water absorption.It analyzes litterfall quantity and decomposition and restitution characteristics and explores the impacts of converting the E.uro-phylla×E.grandis plantations to mixed forest on soil quality.The study also examines the changes in un-derstory plant diversity and evaluates carbon storage and sequestration efficiency.The results showed that the average daily evapotranspiration of a single tree of the E.urophylla×E.grandis was 1.32 mm,and the an-nual evapotranspiration of the E.urophylla×E.grandis was 349 mm,which accounted for 27%of the pre-cipitation of the same year;the annual evapotranspiration of the E.urophylla×E.grandis plantations ac-counted for 82%of the precipitation of the same year.Nitrogen is the most important nutrient returned from apoptosis in the E.urophylla×E.grandis plantations,and the total amount of nutrients returned increased with the age of the forest,and prolonging the cultivation cycle of the E.urophylla×E.grandis helped the decomposition of apoptotic materials and nutrient return to the soil;Pure forest conversion to mixed forests planted with Manglietia glauc significantly improved soil quality.In Guangxi,there are 584 species of vascu-lar plants in 120 families and 369 genera,including 201 species of shrubs and 186 species of herbs in the E.urophylla×E.grandis plantations;it is clear that the middle-aged E.urophylla×E.grandis plantations are carbon sinks during the daytime and carbon sources during the nighttime.In the summer and fall seasons,the plantation forests had the strongest ability to absorb and fix CO2,with a daily net absorption of about 11.0 g·m-2·d-1,which was converted into an annual net fixed carbon of about 10.9 t·hm-2·a-1.Stage-by-stage observations showed that the growth of the E.urophylla×E.grandis did not absorb and consume a large amount of water,and the conversion of pure forest to mixed forest could significantly improve soil quali-ty,and the diversity of plant species in the understory increased with the age of the forest,and the carbon sink function of eucalyptus was stronger than that of other major afforestation species.These findings provide bas-ic information for the objective understanding of the interactions between eucalyptus plantation forests and the ecological environment,and provide theoretical basis for the optimization of eucalyptus plantation forest management plan.关键词
桉树人工林/水分消耗/土壤养分/植物物种多样性/碳汇Key words
Eucalyptus plantation forest/water depletion/soil nutrients/plant species diversity/carbon sinks分类
农业科技引用本文复制引用
任世奇,杜阿朋,胡刚,顾大形,伍琪,韦振道,李昌荣,陈健波..尾巨桉人工林主要生态效应研究[J].广西科学院学报,2023,39(4):393-402,10.基金项目
国家自然科学基金项目(32160362),广西科技基地和人才专项(桂科AD20325008、桂科23-026-272),广西林业科技推广示范项目(桂林科研[2022]第25号)资助. （32160362）
