学术论文

      Subtropical urban turfs: Carbon and nitrogen pools and the role of enzyme activity

      Abstract:
      Urban grasslands not only provide a recreational venue for urban residents,but also sequester organic carbon in vegetation and soils through photosynthesis,and release carbon dioxide through respiration,which largely contribute to carbon storage and fluxes at regional and global scales.We investigated organic carbon and nitrogen pools in subtropical turfs and found that dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) were regulated by several factors including microbial activity which is indicated by soil enzymatic activity.We observed a vertical variation and different temporal patterns in both soil DOC,DON and enzyme activities,which decreased significantly with increasing soil depths.We further found that concentration of soil DON was linked with tuff age.There were correlations between grass biomass and soil properties,and soil enzyme activities.In particular,soil bulk density was significantly correlated with soil moisture and soil organic carbon (SOC).In addition,DOC correlated significantly with DON.Significant negative correlations were also observed between soil total dissolved nitrogen (TDN) and grass biomass of Axonopus compressus and Zoysia matrella.Specifically,grass biomass was significantly correlated with the soil activity of urease and β-glucosidase.Soil NO3-N concentration also showed negative correlations with the activity of both β-glucosidase and protease but there were no significant correlations between cellulase and soil properties or grass biomass.Our study demonstrated a relationship between soil C and N dynamics and soil enzymes that could be modulated to enhance SOC pools through management and maintenance practices.
      Author: Ling Kong LM Chu
      作者单位: School of Life Sciences, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
      刊 名: 环境科学学报(英文版) ISTICEISCI
      年,卷(期): 2018, 65(3)
      在线出版日期: 2018年5月25日
      基金项目: We thank the Hong Kong Cricket Club and the Leisure and Cultural Services Department of the Hong Kong Government for their information provided and permission for sampling for this study.We also thank Miss Po Ying Lai for her advice on data analysis,and Dr Zhengjun Shi from the Shenzhen Key Laboratory of Southern Subtropical Plant Diversity,Fairy Lake Botanical Garden,Shenzhen & Chinese Academy of Sciences for his support and invaluable advice on field sampling in Shenzhen,China.This work was partially supported by a United College Endowment Fund