The Influence of Degradation of Alpine Swamp Wetland On Ecosystem Respiration And Its Components

Abstract Three degradation stages of alpine swamp wetland (none, light and severe degeneration levels) were addressed through measuring the respiratory components rate of ecosystem during the peak period of vegetation growth (July to August), so as to analyze the impacts of degradation on ecosystem respiration and its components in alpine swamp wetland on the Qinghai-Tibet Plateau. Two methods which are root separation and herbicide spraying, were used for determination and measurement of respiratory components. The results showed that degradation of alpine swamp wetland can significantly increase soil respiration rate and microbial respiration rate. Moreover, the proportion of vegetation respiration and microbial respiration in ecosystem respiration changed significantly (P < 0.05). There was a significant positive correlation between vegetation respiration and ecosystem respiration rate at all the degradation levels (P < 0.05). Canopy respiration and ecosystem respiration were highly correlated between none and severe degraded wetlands (P < 0.05), it was also found that there was significant positive correlation among soil respiration rate, root respiration rate and ecosystem respiration in light degraded wetland. There was a positive correlation between root respiration and soil respiration in none and light degraded wetland (P < 0.05). The Q10 change ranges of ecosystem respiration, vegetation respiration, canopy respiration, soil respiration, root respiration and soil microbial respiration during the degradation stage of alpine swamp wetland were 1.41–1.50, 1.81–1.94, 4.46–6.93, 1.41–2.40, 2.84–5.97 and 1.99–3.74, respectively. The degradation of alpine wetland affects firstly the ecosystem respiration and its components, and then will affect the carbon cycle process. Therefore, it is very important to protect and restore the alpine wetland on the Qinghai-Tibet Plateau.