Flux Tower Completed
Supporting UNESCO Global Geopark Creation
Plantations are a major means of forest carbon sequestration, and the development of plantations has become a strategic choice for China to achieve its “carbon peaking and carbon neutrality” goals. In recent years, Zanhuang County has carried out afforestation covering approximately 65,000 mu, rapidly increasing forest area and effectively enhancing the carbon sink function of mountain plantation ecosystems. A carbon flux system is an important tool for studying carbon dioxide exchange between the forest canopy and the atmosphere, especially for quantifying the long-term carbon capture capacity of plantations and other key meteorological parameters. Based on this, the construction of the eddy covariance flux tower will help deepen the understanding of the carbon sink service potential of afforestation ecosystems in the Taihang Mountains at the site level, and help identify better regional forest management and protection methods at the broader area level.
I. Introduction to Eddy Covariance Flux Equipment
The eddy covariance flux equipment includes one open-path eddy covariance system and one conventional micrometeorological observation system. The open-path eddy covariance system is mainly composed of an open-path infrared CO2/H2O analyzer (LI-7500, LICOR) and a three-dimensional sonic anemometer (CSAT-3, CSI). While collecting real-time data, the system automatically calculates flux data and records 30-minute averages. The conventional meteorological observation system includes: a net radiometer for measuring net radiation; a photosynthetically active radiation quantum sensor for measuring photosynthetically active radiation; an air temperature and humidity sensor for measuring air temperature and humidity; a rain gauge for measuring rainfall; a soil moisture observation instrument for measuring soil water content at 0–10 cm; soil temperature sensors placed 5 cm, 10 cm, and 20 cm below the ground surface for measuring soil temperature; and three soil heat flux plates installed 2 cm below the ground surface for measuring soil heat flux. Meteorological data are stored as half-hour averages.
II. Land Occupation for Flux Tower Installation
The research site is located northeast of Yanjiayu Village in Zanhuang County, approximately 18 km from the county seat. The afforestation area covers 6,600 mu and mainly consists of Chinese arborvitae (70%) and mountain apricot (30%). The flux tower is planned to be installed in the central area of the plantation. A pit approximately 1.5 meters in diameter and 1.7 meters deep will be excavated on the mountaintop, and concrete will be poured to build the tower foundation. The designed height of the flux tower is 12 meters, with an additional 1.5-meter lightning rod. Meanwhile, a 4 m × 4 m fence will be installed around the tower to protect it from damage.
III. Introduction to the Scientific Research Project
Based on eddy covariance technology, long-term continuous observations will be carried out on carbon and water fluxes in young plantations in the mountainous areas of Zanhuang County. The project will analyze the daily, monthly, and interannual dynamic changes of carbon fluxes and clarify the response relationship between net ecosystem carbon exchange and environmental factors. This will help analyze the carbon budget and carbon sequestration capacity of plantations. The research results can be used to estimate, simulate, and predict net carbon exchange in similar ecosystems. They can also serve as an important theoretical basis for carbon management in plantation ecosystems and responses to climate change, providing theoretical support and technical guidance for plantation ecological benefit management and decision-making aimed at increasing carbon sinks and reducing emissions.
