Variation in NEE and its response to environmental factors in an extremely arid desert wetland ecosystem

Abstract

In order to study the net ecosystem CO₂ exchange (NEE) variation and its response to environmental factors, CO₂ flux and related environmental factors were monitored from May until September. The diurnal NEE variations in this region showed a U-shaped distribution. The average daily CO₂ absorption in July was the largest. The study area is a carbon sink during the growing season. At the soil depth of 40 and 80 cm, due to the influence of underground water, the soil water content had a significantly negative correlation with NEE. The increase in relative air humidity can facilitate stomata opening, which also improves CO₂ absorption. Additionally, the increase in air temperature, soil temperature and photosynthetically active radiation (PAR) all promote plant photosynthesis, which leads to a negative correlation with NEE.