Welcome to visit Scientia Silvae Sinicae，Today is

Scientia Silvae Sinicae ›› 2025, Vol. 61 ›› Issue (4): 69-80.doi: 10.11707/j.1001-7488.LYKX20240535

• Research papers • Previous Articles    

Growing Season Dynamics and Influencing Factors of Resource Use Efficiency of a Larix gmelinii var. principis-rupprechtii Natural Secondary Forest in Baihuashan, Beijing

Li Qinyuan1,2,3, Zhou Zeyuan4, Li Tingshan5, Yu Haiqun4, Zhao Hongxian1,2,3, Liu Xinyue1,2,3, Gao Yao1,2,3, Liu Peng1,2,3, Zha Tianshan1,2,3   

  1. 1. National Key Laboratory of Efficient Production of Forest Resources, Beijing Forestry University　Beijing 100083;
    2. College of Soil and Water Conservation, Beijing Forestry University　Beijing 100083;
    3. Beijing Soil and Water Conservation Engineering Research Center　Beijing 100083;
    4. Beijing Landscape Planning and Resources Monitoring Center　Beijing 101118;
    5. China Railway Academy Group Co., Ltd.　Chengdu 610032
  • Received:2024-09-17 Revised:2025-02-25 Published:2025-04-21

PDF (PC)

19

Abstract: Objective This study aims to explore the seasonal variation within the growing season of carbon, light, water use efficiencies in a Larix gmelinii var. principis-rupprechtii natural secondary forest, analyze their biophysical influence and the trade-off among carbon, light, water use efficiencies. Method The eddy covariance technique was used to continuously monitor ecosystem carbon and water fluxes in a L. gmelinii var. principis-rupprechtii natural secondary forest in Baihuashan, Beijing. Air temperature, soil temperature and soil water content were continuously monitor. The seasonal variations of ecosystem carbon, light, water use efficiencies were analyzed, along with their biophysical influence, and the trade-off relationships among resource use efficiencies were examined. Result 1) During the growing season, carbon use efficiency was small in June and large in October, ranging from 0.14 to 0.97. Light use efficiency was large in August and small in October, ranging from 0.15 to 2.19 g·MJ-1. Water use efficiency was small in June and large in October, ranging from 0.74 to 8.00 g·kg-1. 2) Carbon use efficiency was significantly negatively correlated with soil temperature（P < 0.05）, light use efficiency was significantly positively correlated with soil water content（P < 0.05）, water use efficiency was significantly negatively correlated with soil water content（P < 0.05）. The structural equation model showed that soil temperature had a negative effect on carbon use efficiency, by affecting ecosystem respiration（P < 0.05）. Diffuse radiation had a positive effect on light use efficiency, by affecting gross primary productivity（P < 0.05）. Vapor pressure deficit had a negative effect on water use efficiency, by affecting evapotranspiration（P < 0.05）. 3) Carbon use efficiency was significantly positively correlated with water use efficiency（P < 0.01）, higher light use efficiency was observed when both carbon and water use efficiencies were low. Conclusion The carbon use efficiency and water use efficiency followed the same trend in L. gmelinii var. principis-rupprechtii natural secondary forest ecosystem, both declined in the middle of the growing season, and light use efficiency reached the maximum value in the middle of the growing season. Increasing soil temperature decreased the carbon use efficiency. Increasing soil water content and diffuse radiation promoted the light use efficiency. Increasing soil water content and vapor pressure deficit decreased the water use efficiency. There is a trade-off between ecosystem resource use efficiency, higher light use efficiency occurred when both carbon and water use efficiencies were low. Our findings highlight importance of water condition in the trade-off between resource use efficiency in L. gmelinii var. principis-rupprechtii natural secondary forest ecosystem.

Key words: carbon use efficiency, light use efficiency, water use efficiency, seasonal variability, trade-off relationship

CLC Number: