Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Master → Chine → 2021 → Changes in Root Morphological Traits and Biomass of Grassland Plant along the Environmental Gradient in the Loess Plateau

Northwest A&F University (2021)

Changes in Root Morphological Traits and Biomass of Grassland Plant along the Environmental Gradient in the Loess Plateau

孙天雨

Titre : Changes in Root Morphological Traits and Biomass of Grassland Plant along the Environmental Gradient in the Loess Plateau

Auteur : 孙天雨

Grade : Master 2021

Université : Northwest A&F University

Résumé partiel
Grassland is an important part of terrestrial ecosystem,and the root morphology and biomass are important parameters in the study of grassland ecosystem.It is of great significance to study the variation in the root morphology and biomass along the environmental gradient for the local vegetation construction and restoration.In this study,we selected ten sites from east to west in the Loess Plateau,which covered the main grassland types,including forest grassland,typical grassland and desert grassland.At each site,the roots of grassland plant were sampled to 0 cm to 50 cm soil depth at eight experimental plots(1m×1 m)by using roots cores.Root morphological trait(including total root length and total root surface area)and biomass of each soil depth were determined.We aimed to analyze the variation of root morphological traits(including total root length and total root surface area)and biomass along the environmental gradient in the Loess Plateau and their influence factors.The results showed that :(1)The total root length was significantly different among three grassland types(P<0.05),and the root length of forest steppe was significantly higher than that of typical steppe and desert steppe.The root length of the three grassland types was mainly distributed in the surface soil(0-10 cm),and the root length of the forest steppe was most distributed in the surface soil,and the root length of deep layer(10-50 cm)of desert steppe accounted for more of the total root length of desert steppe.With the increase of longitude,the root length of grassland in the Loess Plateau showed a gradually increasing geographical pattern,and more roots appeared in the shallow soil.Root length had significant positive correlation with climate and soil factors(P<0.01).The ratio of shallow root length to deep root length(i.e.,shallow-deep ratio of length)was positively correlated with average annual precipitation(MAP)and soil total nitrogen content(TN)(P<0.01),and negatively correlated with soil p H(P<0.01).Environmental factors explained 37.2%-48.94% of the variation in root length of grassland in the Loess Plateau,and climate factors explained the most variation(5.2%-18.46%)of root length.The interaction of climate factors and soil factors could explain 18.25%-37.03% of variability.(2)The total root surface area was significantly different among three grassland types(P<0.01),and the root surface area of forest steppe was significantly higher than those of typical steppe and desert steppe.The root surface area of the three grassland types mainly concentrated in the surface soil,and the root surface area of forest steppe and typical steppe was more in the surface soil,and the root surface area of deep desert steppe accounted for more in the total root surface area of desert steppe.With the increase of longitude,the root surface area of grassland in the Loess Plateau showed a gradually increasing geographical pattern,and more roots appeared in the shallow soil.Root surface area had significant positive correlation with climate and soil factors(P<0.01).The ratio of shallow root surface area to deep root surface area(i.e.,shallow-deep ratio of surface area)was significantly positively correlated with MAP and TN(P<0.01),and negatively correlated with soil p H(P<0.01).Environmental factors explained 39.07%-52.24% of the variation in the root surface area of grassland in the Loess Plateau,and climate factors accounted for the most variation(9.36%-23.17%).The interaction of climate factors and soil factors could explain 23.28%-35.44% of the variability.

Mots clés : Loess Plateau ;grassland;root length ;root surface area ;root biomass ;

Présentation (CNKI) -> https://oversea.cnki.net/KCMS/detai...

Page publiée le 13 novembre 2021