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

Accueil du site → Master → Chine → 2020 → Response of Soil Respiration and Microbial Activities to the Desert Grassland-Shrubland State Anthropogenic Transition in the Eastern of Ningxia,China

Ningxia University (2020)

Response of Soil Respiration and Microbial Activities to the Desert Grassland-Shrubland State Anthropogenic Transition in the Eastern of Ningxia,China

郭天斗

Titre : Response of Soil Respiration and Microbial Activities to the Desert Grassland-Shrubland State Anthropogenic Transition in the Eastern of Ningxia,China

Auteur : 郭天斗

Grade : Master’s Theses 2020

Université : Ningxia University

Résumé partiel
We selected a typical grassland-shrubland mosaics formed by the anthropogenic introduction of shrub in the desert grasslands of eastern Ningxia as our research object,the four transition sites in the mosaic,desert grassland(DG),grassland edge(GE),and shrubland edge(SE),shrubland(SL),were selected based on the ecological boundary theory.We conducted the field investigation,different rainfall gradient control experiments,different water pulse and litter addition in the laboratory test to study the vegetation changes and soil respiration and soil microbial response characteristics(quantity,biomass,functional diversity,microbial enzymes)in different microhabitats(vegetation patch and bare interspace)of each site in the process of the anthropogenic transition from desert grassland to shrubland with an aim to understand the direct and indirect effects of vegetation transition and global precipitation change on soil respiration and soil microbial enzyme activities.The main conclusions were obtained as follows:1.Soil moisture,organic carbon and total nitrogen all showed a decreasing trend,soil porosity and water holding capacity showed a trend of rising and then falling,and the soil bulk density,total phosphorus and pH decreased first and then increased with the four sites transition.The soil physical and chemical properties were significantly lower in the shrubland than that in the desert grassland,and most of the soil physical and chemical properties were higher in vegetation patches than in bare interspaces in each site,especially in the shrubland.Except soil bulk density and pH had the negative correlations with other soil factors,other soil physical and chemical properties were positively intercorrelated.With the transition the aboveground and underground biomass and the total amount of litter biomass increased gradually,and the difference between shrubland and other sites was significant(P<0.05)

Mots clés : desert grassland; grassland-shrubland state transition; soil physical and chemical characteristics; soil respiration; soil enzyme activitie;

Présentation (CNKI)

Page publiée le 31 mars 2022