Cdynamic Change Characteristics of Ecosystem Fluxes in Cold Zone Wetlands in Northeast China

Abstract

In order to promote the understanding of the dynamic change characteristics of ecosystem flux in cold zone wetlands and to provide scientific basis for the accurate simulation of wetland flux, this study applied the eddy covariance (EC) flux measurement system for long-term continuous flux of Harbin Jinhewan Wetland Botanical Garden. A preliminary analysis of one-and-a-half-year measurements of water, heat, and CO2 fluxes showed that: (1) The diurnal variation of CO2 flux shows a single-valley character, and the annual variation is consistent with the vegetation growth trend; the diurnal variation of CO2 concentration shows a single-peak and single-valley character, the annual change process is opposite to the vegetation growth trend. (2) The average daily CO2 absorption rate of Jinhewan Wetland is only 0.13 mg/(m 2 •s), with weak carbon sink function and great carbon sequestration potential. (3) The diurnal variations of sensible heat flux (SHF), latent heat flux (LHF) and Bowen ratio (except for winter) of Jinhewan Wetland are basically single-peaked; SHF is highest in spring and LHF is highest in summer; LHF is only smaller than SHF in winter, while in summer LHF is much larger than SHF and minimum is two times that of SHF.

Phytoplankton alpha diversity indices response the trophic state variation in hydrologically connected aquatic habitats in the Harbin Section of the Songhua River

“…During the connected period, the inflow coming from the HSSR flows through the JHWW and finally into the HSSR. The Jinhewan Wetland (JHWW) is located in the middle streams of the Harbin Section of the Songhua River, which is a demonstration area for the protection and restoration of aquatic ecosystems in Harbin, and is a vital part of the ecological project of the “Hectares of Songjiang Wetland and Long-stretching Ecological Corridor” 17 . The JHWW is the main inflow channel with a volume of 3 × 10 5 m 3 water, contributing more than 30% of the total inflows of HSSR.…”